WiMAX today and tomorrow

WiMAX today

Despite the all-round occurrence of the WiMAX still in the design even in the most developed countries, introduction of the standard is progressing at an enviable pace. Quite recently, last autumn during the days of Intel Developers' Forum in the building of Russian Academy of Sciences the experimental network IEEE802.16-2004 was demonstrated in action. And last week in Kiev, Ukraine, Ukrainian advanced technologies commissioned the first in the ex-USSR network of wireless broadband access to Internet on the base of the WiMAX technology. From that week onwards, the network by "Ukrainian Advanced Technologies" dubbed ALTERNET started rendering services of wireless broadband access to Internet on the base of WiMAX using client devices built on the Intel PRO/Wireless 5116 chipset.

The services are about fixed wireless access to Internet using the WiMAX technology based on the Alvarion client equipment built on the Intel PRO/Wireless 5116 chipset. They are offered to companies and private persons who are based in the areas of poorly developed or outdated cable infrastructure. "Ukrainian Advanced Technologies" intends to provide its services on a turn-key basis in merely two days after the first customer's call. Today, you can subscribe to the services in Kiev and Kharkov. There are plans for the first quarter of the next year to establish regional offices to render the access services in Dnepropetrovsk, Odessa, Donetsk, and Lvov. On the whole, it is planned to provide WiMAX connection facilities in all the regional centers of Ukraine by the end of 2006.

In fact, you shouldn't think that some sort of a WiMAX anomaly is going on in the Ukraine. Introduction of WiMAX networks is going on continuously these days, announcements of launching such networks are appearing every day, and only in Russia this issue is being solved extremely slowly (read below).

Modern hardware for WiMAX

As regards the capabilities of PRO/Wireless 5116 chipset officially presented by Intel in April 2005, it proved to be one of the first products in the industry with support for the WiMAX standard. This Intel chipset is made in a 360-pin PBGA casing, offers functionality needed to implement establish economical high-speed wireless modems for the home and office. Solutions based on PRO/Wireless 5116 allow providing broadband access to the Internet in remote areas where no DSL or cable networks are there and establish communication between tasks distributed a few miles apart.

Combined with a RF module and a third-party amplifier, the SoC system Intel PRO/Wireless 5116 with support for IEEE 802.16-2004, formerly known as the Rosedale, provides the possibility to use WiMAX networks for a wide circle of users.. At the same time, the Intel PRO/Wireless 5116 interface supports not only external but internal solutions, e.g. WiMAX subscriber modems and home-based gateways.

Intel PRO/Wireless 5116 (Rosedale)

WiMAX Forum. Intel's role in establishing the standard

For the purposes of testing, standardization, certification and marketing of WiMAX products, the WiMAX Forum industry alliance has been established. It's just this alliance that issues "WiMAX Forum Certified" verdicts. By now, the number of WiMAX Forum members is rapidly approaching to 200, and over one quarter of the number are operators who are rendering provider services based on the WiMAX technology.

Once of the most active member of the WiMAX Forum alliance is Intel who participates in all the undertakings – from problem statement up to the ratification of standards and development of end equipment. Intel is now cooperating with companies who have deployed pre-standardized WiMAX broadband wireless networks in over than 125 countries. They offer a wide range of options - from stationary systems of wireless access up to enterprise-scale point-to-point data transmission systems.

For the purposes of testing, standardization, certification and marketing of WiMAX products, the WiMAX Forum industry alliance has been established. It's just this alliance that issues "WiMAX Forum Certified" verdicts. By now, the number of WiMAX Forum members is rapidly approaching to 200, and over one quarter of the number are operators who are rendering provider services based on the WiMAX technology. Apart from Intel Corporation, other known companies participate in the WiMAX Forum, among them Airspan Networks, Alvarion, Aperto Networks, Ensemble Communications, Fujitsu Microelectronics America, Nokia, OFDM Forum, Proxim Corporation, Wi-LAN Inc. and others.

One of the most active member of the WiMAX Forum alliance is Intel who participates in all the undertakings – from problem statement up to the ratification of standards and development of end equipment. Intel is now cooperating with companies who have deployed pre-standardized WiMAX broadband wireless networks in over than 125 countries. They offer a wide range of options - from stationary systems of wireless access up to enterprise-scale point-to-point data transmission systems.

Among the operators collaborating with Intel at the promoting of WiMAX solutions are AT&T (USA), Altitude Telecom (France), BT (U.K.), Brazil Telecom (Brazil), ETB (Columbia), Iberbanda (Spain), Millicom (Argentina), Qwest (USA), Sify (India), Speakeasy (USA), Telkom (South Africa), Telmex (Mexico), TowerStream (USA), and the already mentioned "Ukrainian Advanced Technologies" (Ukraine). The release of produce manufactured on the base of Intel PRO/Wireless 5116 has been announced by Airspan, Alvarion, Aperto Networks, Axxcelera Broadband Wireless, Gemtek, Huawei, Proxim Corporation, Redline Communications, Siemens Mobile, SR Telecom, and ZTE.

Remarkably, these days Motorola and Intel announced their joint plans for promoting the IEEE 802.16e-based WiMAX technology for mobile solutions and which is applicable to both stationary and wireless devices fir broadband communications. Apart from promoting the WiMAX standards, the joint plans of these companies include tests of mobile devices, networked and subscriber end equipment made by Motorola for compatibility to Intel's produce.

WiMAX in Russia

Late in October, the first in Russia seminar on using the WiMAX arranged by Intel was held in Nizhny Novgorod. The seminar gathered representatives, telecommunication companies, providers, developers and manufacturers of wireless communications equipment, as well as government institutions in charge of frequency regulations and licensing. During the event, Intel representatives demonstrated a model of operating network built on the base of the Intel Pro/Wireless 5116 chipset.

Alas - not all are as enthusiastic as Intel. As regards the real dates for introduction of a new backbone wireless standard in Russia, many analysts agree that formation of WiMAX networks in Russia will not start earlier than the summer of 2006. Many pledge to the incomplete certification for WiMAX equipment, many complain about the high price of first-generation WiMAX solutions, but in general there is a lack of intention from the side of providers to spend for a technology which is unlikely to pay back soon. In large cities where there are still more than enough facilities for fast-speed Internet access, the Wi-Fi capacity is still enough. As regards deployment of WiMAX networks somewhere in remote areas in Russia, no one is yet planning to do so at the first stage. Of course, there will be isolated instances of WiMAX network deployment, but we won't hear about them in the near future. But while there is little interest from administrative bodies and lack funding all these events will still be unique.

In a word, many agree that WiMAX networks are unlikely to go beyond the boundaries of large Russian cities earlier than 2009. At the same time, in the Net you can find a variety of contrary opinions stating that if introduction of WiMAX networks at the first stage proves successful, their number may go up as a snowball within short terms.

Perhaps I'd rather stop my today's story at the note of uncertainty. Early in 2006, the WiMAX standard is in for another epochal event and we'll hope that by that time the news on Russian market of WiMAX networks will be more optimistic.

WiMAX today and tomorrow

WiMAX today

Despite the all-round occurrence of the WiMAX still in the design even in the most developed countries, introduction of the standard is progressing at an enviable pace. Quite recently, last autumn during the days of Intel Developers' Forum in the building of Russian Academy of Sciences the experimental network IEEE802.16-2004 was demonstrated in action. And last week in Kiev, Ukraine, Ukrainian advanced technologies commissioned the first in the ex-USSR network of wireless broadband access to Internet on the base of the WiMAX technology. From that week onwards, the network by "Ukrainian Advanced Technologies" dubbed ALTERNET started rendering services of wireless broadband access to Internet on the base of WiMAX using client devices built on the Intel PRO/Wireless 5116 chipset.

The services are about fixed wireless access to Internet using the WiMAX technology based on the Alvarion client equipment built on the Intel PRO/Wireless 5116 chipset. They are offered to companies and private persons who are based in the areas of poorly developed or outdated cable infrastructure. "Ukrainian Advanced Technologies" intends to provide its services on a turn-key basis in merely two days after the first customer's call. Today, you can subscribe to the services in Kiev and Kharkov. There are plans for the first quarter of the next year to establish regional offices to render the access services in Dnepropetrovsk, Odessa, Donetsk, and Lvov. On the whole, it is planned to provide WiMAX connection facilities in all the regional centers of Ukraine by the end of 2006.

In fact, you shouldn't think that some sort of a WiMAX anomaly is going on in the Ukraine. Introduction of WiMAX networks is going on continuously these days, announcements of launching such networks are appearing every day, and only in Russia this issue is being solved extremely slowly (read below).

Modern hardware for WiMAX

As regards the capabilities of PRO/Wireless 5116 chipset officially presented by Intel in April 2005, it proved to be one of the first products in the industry with support for the WiMAX standard. This Intel chipset is made in a 360-pin PBGA casing, offers functionality needed to implement establish economical high-speed wireless modems for the home and office. Solutions based on PRO/Wireless 5116 allow providing broadband access to the Internet in remote areas where no DSL or cable networks are there and establish communication between tasks distributed a few miles apart.

Combined with a RF module and a third-party amplifier, the SoC system Intel PRO/Wireless 5116 with support for IEEE 802.16-2004, formerly known as the Rosedale, provides the possibility to use WiMAX networks for a wide circle of users.. At the same time, the Intel PRO/Wireless 5116 interface supports not only external but internal solutions, e.g. WiMAX subscriber modems and home-based gateways.

Intel PRO/Wireless 5116 (Rosedale)

WiMAX Forum. Intel's role in establishing the standard

For the purposes of testing, standardization, certification and marketing of WiMAX products, the WiMAX Forum industry alliance has been established. It's just this alliance that issues "WiMAX Forum Certified" verdicts. By now, the number of WiMAX Forum members is rapidly approaching to 200, and over one quarter of the number are operators who are rendering provider services based on the WiMAX technology.

Once of the most active member of the WiMAX Forum alliance is Intel who participates in all the undertakings – from problem statement up to the ratification of standards and development of end equipment. Intel is now cooperating with companies who have deployed pre-standardized WiMAX broadband wireless networks in over than 125 countries. They offer a wide range of options - from stationary systems of wireless access up to enterprise-scale point-to-point data transmission systems.

For the purposes of testing, standardization, certification and marketing of WiMAX products, the WiMAX Forum industry alliance has been established. It's just this alliance that issues "WiMAX Forum Certified" verdicts. By now, the number of WiMAX Forum members is rapidly approaching to 200, and over one quarter of the number are operators who are rendering provider services based on the WiMAX technology. Apart from Intel Corporation, other known companies participate in the WiMAX Forum, among them Airspan Networks, Alvarion, Aperto Networks, Ensemble Communications, Fujitsu Microelectronics America, Nokia, OFDM Forum, Proxim Corporation, Wi-LAN Inc. and others.

One of the most active member of the WiMAX Forum alliance is Intel who participates in all the undertakings – from problem statement up to the ratification of standards and development of end equipment. Intel is now cooperating with companies who have deployed pre-standardized WiMAX broadband wireless networks in over than 125 countries. They offer a wide range of options - from stationary systems of wireless access up to enterprise-scale point-to-point data transmission systems.

Among the operators collaborating with Intel at the promoting of WiMAX solutions are AT&T (USA), Altitude Telecom (France), BT (U.K.), Brazil Telecom (Brazil), ETB (Columbia), Iberbanda (Spain), Millicom (Argentina), Qwest (USA), Sify (India), Speakeasy (USA), Telkom (South Africa), Telmex (Mexico), TowerStream (USA), and the already mentioned "Ukrainian Advanced Technologies" (Ukraine). The release of produce manufactured on the base of Intel PRO/Wireless 5116 has been announced by Airspan, Alvarion, Aperto Networks, Axxcelera Broadband Wireless, Gemtek, Huawei, Proxim Corporation, Redline Communications, Siemens Mobile, SR Telecom, and ZTE.

Remarkably, these days Motorola and Intel announced their joint plans for promoting the IEEE 802.16e-based WiMAX technology for mobile solutions and which is applicable to both stationary and wireless devices fir broadband communications. Apart from promoting the WiMAX standards, the joint plans of these companies include tests of mobile devices, networked and subscriber end equipment made by Motorola for compatibility to Intel's produce.

WiMAX in Russia

Late in October, the first in Russia seminar on using the WiMAX arranged by Intel was held in Nizhny Novgorod. The seminar gathered representatives, telecommunication companies, providers, developers and manufacturers of wireless communications equipment, as well as government institutions in charge of frequency regulations and licensing. During the event, Intel representatives demonstrated a model of operating network built on the base of the Intel Pro/Wireless 5116 chipset.

Alas - not all are as enthusiastic as Intel. As regards the real dates for introduction of a new backbone wireless standard in Russia, many analysts agree that formation of WiMAX networks in Russia will not start earlier than the summer of 2006. Many pledge to the incomplete certification for WiMAX equipment, many complain about the high price of first-generation WiMAX solutions, but in general there is a lack of intention from the side of providers to spend for a technology which is unlikely to pay back soon. In large cities where there are still more than enough facilities for fast-speed Internet access, the Wi-Fi capacity is still enough. As regards deployment of WiMAX networks somewhere in remote areas in Russia, no one is yet planning to do so at the first stage. Of course, there will be isolated instances of WiMAX network deployment, but we won't hear about them in the near future. But while there is little interest from administrative bodies and lack funding all these events will still be unique.

In a word, many agree that WiMAX networks are unlikely to go beyond the boundaries of large Russian cities earlier than 2009. At the same time, in the Net you can find a variety of contrary opinions stating that if introduction of WiMAX networks at the first stage proves successful, their number may go up as a snowball within short terms.

Perhaps I'd rather stop my today's story at the note of uncertainty. Early in 2006, the WiMAX standard is in for another epochal event and we'll hope that by that time the news on Russian market of WiMAX networks will be more optimistic.

WiMAX today and tomorrow

WiMAX today

Despite the all-round occurrence of the WiMAX still in the design even in the most developed countries, introduction of the standard is progressing at an enviable pace. Quite recently, last autumn during the days of Intel Developers' Forum in the building of Russian Academy of Sciences the experimental network IEEE802.16-2004 was demonstrated in action. And last week in Kiev, Ukraine, Ukrainian advanced technologies commissioned the first in the ex-USSR network of wireless broadband access to Internet on the base of the WiMAX technology. From that week onwards, the network by "Ukrainian Advanced Technologies" dubbed ALTERNET started rendering services of wireless broadband access to Internet on the base of WiMAX using client devices built on the Intel PRO/Wireless 5116 chipset.

The services are about fixed wireless access to Internet using the WiMAX technology based on the Alvarion client equipment built on the Intel PRO/Wireless 5116 chipset. They are offered to companies and private persons who are based in the areas of poorly developed or outdated cable infrastructure. "Ukrainian Advanced Technologies" intends to provide its services on a turn-key basis in merely two days after the first customer's call. Today, you can subscribe to the services in Kiev and Kharkov. There are plans for the first quarter of the next year to establish regional offices to render the access services in Dnepropetrovsk, Odessa, Donetsk, and Lvov. On the whole, it is planned to provide WiMAX connection facilities in all the regional centers of Ukraine by the end of 2006.

In fact, you shouldn't think that some sort of a WiMAX anomaly is going on in the Ukraine. Introduction of WiMAX networks is going on continuously these days, announcements of launching such networks are appearing every day, and only in Russia this issue is being solved extremely slowly (read below).

Modern hardware for WiMAX

As regards the capabilities of PRO/Wireless 5116 chipset officially presented by Intel in April 2005, it proved to be one of the first products in the industry with support for the WiMAX standard. This Intel chipset is made in a 360-pin PBGA casing, offers functionality needed to implement establish economical high-speed wireless modems for the home and office. Solutions based on PRO/Wireless 5116 allow providing broadband access to the Internet in remote areas where no DSL or cable networks are there and establish communication between tasks distributed a few miles apart.

Combined with a RF module and a third-party amplifier, the SoC system Intel PRO/Wireless 5116 with support for IEEE 802.16-2004, formerly known as the Rosedale, provides the possibility to use WiMAX networks for a wide circle of users.. At the same time, the Intel PRO/Wireless 5116 interface supports not only external but internal solutions, e.g. WiMAX subscriber modems and home-based gateways.

Intel PRO/Wireless 5116 (Rosedale)

WiMAX Forum. Intel's role in establishing the standard

For the purposes of testing, standardization, certification and marketing of WiMAX products, the WiMAX Forum industry alliance has been established. It's just this alliance that issues "WiMAX Forum Certified" verdicts. By now, the number of WiMAX Forum members is rapidly approaching to 200, and over one quarter of the number are operators who are rendering provider services based on the WiMAX technology.

Once of the most active member of the WiMAX Forum alliance is Intel who participates in all the undertakings – from problem statement up to the ratification of standards and development of end equipment. Intel is now cooperating with companies who have deployed pre-standardized WiMAX broadband wireless networks in over than 125 countries. They offer a wide range of options - from stationary systems of wireless access up to enterprise-scale point-to-point data transmission systems.

For the purposes of testing, standardization, certification and marketing of WiMAX products, the WiMAX Forum industry alliance has been established. It's just this alliance that issues "WiMAX Forum Certified" verdicts. By now, the number of WiMAX Forum members is rapidly approaching to 200, and over one quarter of the number are operators who are rendering provider services based on the WiMAX technology. Apart from Intel Corporation, other known companies participate in the WiMAX Forum, among them Airspan Networks, Alvarion, Aperto Networks, Ensemble Communications, Fujitsu Microelectronics America, Nokia, OFDM Forum, Proxim Corporation, Wi-LAN Inc. and others.

One of the most active member of the WiMAX Forum alliance is Intel who participates in all the undertakings – from problem statement up to the ratification of standards and development of end equipment. Intel is now cooperating with companies who have deployed pre-standardized WiMAX broadband wireless networks in over than 125 countries. They offer a wide range of options - from stationary systems of wireless access up to enterprise-scale point-to-point data transmission systems.

Among the operators collaborating with Intel at the promoting of WiMAX solutions are AT&T (USA), Altitude Telecom (France), BT (U.K.), Brazil Telecom (Brazil), ETB (Columbia), Iberbanda (Spain), Millicom (Argentina), Qwest (USA), Sify (India), Speakeasy (USA), Telkom (South Africa), Telmex (Mexico), TowerStream (USA), and the already mentioned "Ukrainian Advanced Technologies" (Ukraine). The release of produce manufactured on the base of Intel PRO/Wireless 5116 has been announced by Airspan, Alvarion, Aperto Networks, Axxcelera Broadband Wireless, Gemtek, Huawei, Proxim Corporation, Redline Communications, Siemens Mobile, SR Telecom, and ZTE.

Remarkably, these days Motorola and Intel announced their joint plans for promoting the IEEE 802.16e-based WiMAX technology for mobile solutions and which is applicable to both stationary and wireless devices fir broadband communications. Apart from promoting the WiMAX standards, the joint plans of these companies include tests of mobile devices, networked and subscriber end equipment made by Motorola for compatibility to Intel's produce.

WiMAX in Russia

Late in October, the first in Russia seminar on using the WiMAX arranged by Intel was held in Nizhny Novgorod. The seminar gathered representatives, telecommunication companies, providers, developers and manufacturers of wireless communications equipment, as well as government institutions in charge of frequency regulations and licensing. During the event, Intel representatives demonstrated a model of operating network built on the base of the Intel Pro/Wireless 5116 chipset.

Alas - not all are as enthusiastic as Intel. As regards the real dates for introduction of a new backbone wireless standard in Russia, many analysts agree that formation of WiMAX networks in Russia will not start earlier than the summer of 2006. Many pledge to the incomplete certification for WiMAX equipment, many complain about the high price of first-generation WiMAX solutions, but in general there is a lack of intention from the side of providers to spend for a technology which is unlikely to pay back soon. In large cities where there are still more than enough facilities for fast-speed Internet access, the Wi-Fi capacity is still enough. As regards deployment of WiMAX networks somewhere in remote areas in Russia, no one is yet planning to do so at the first stage. Of course, there will be isolated instances of WiMAX network deployment, but we won't hear about them in the near future. But while there is little interest from administrative bodies and lack funding all these events will still be unique.

In a word, many agree that WiMAX networks are unlikely to go beyond the boundaries of large Russian cities earlier than 2009. At the same time, in the Net you can find a variety of contrary opinions stating that if introduction of WiMAX networks at the first stage proves successful, their number may go up as a snowball within short terms.

Perhaps I'd rather stop my today's story at the note of uncertainty. Early in 2006, the WiMAX standard is in for another epochal event and we'll hope that by that time the news on Russian market of WiMAX networks will be more optimistic.

WiMAX: wireless highway to the future

By: Vladimir Romanchenko

At first, there was the cable. No, that's wrong. First, there was the word, of course, and then the deed which resulted later in computers and other electronics - from super-clusters to mobiles. Then there rose the need for interaction among all this electronics. This is the way how the cable came into being, that is, first hard-wire interfaces. Then wireless, as technologies progressed. Leaving this long and sometimes heroic past of hard-wire networks outside the note, let's move on to the most interesting part - the current situation and the nearest future wireless prospects.

Separate Wi-Fi access points that could be plugged in to powerful backbone "hard-wire" networks, e.g. fiber-optical, were the first timid moves towards creation of wireless networks. Then there came up a new class of providers who deployed numerous commercial networks, thus in a matter of few years Wi-Fi networks turned into serious infrastructures - corporate and public. By now, many hotels, airports, and railway stations of the world have acquired Wi-Fi networks, and in some countries residential communities are covered this way.

No doubt, introduction of Wi-Fi wireless networks has proved a revolutionary solution to the "last mile" problem. However, the standard's original limitations for data exchange rate and range, number of channels, high cost of the infrastructure have not yet made it possible for Wi-Fi to become a total threat to cellular networks on the one hand, and hard-wire networks, on the other. Even despite the substantial advantages and introduction of new, more up-to-date versions of the standard, the "native limitations" of Wi-Fi will be eliminated only through new backbone standards for data exchange. Sort of WiMAX.

WiMAX Definition

WiMAX stands for Worldwide Interoperability for Microwave Access, and is a technology of broadband wireless communication standardized by the IEEE which complements DSL lines and cable technologies as an alternative solution to the "last mile" problem at great distances. The WiMAX technology can be used to implement broadband "last mile" connections, deployment of wireless access point, arrangement of high-speed communication among company branches and solution of other similar tasks.

Evolution of WiMAX

The preliminary version of WiMAX provided functionality with the equipment which was not subject to standard tests for compatibility to the WiMAX technology. A number of service providers are still using such preliminary hardware solutions to implement WiMAX pilot projects in many parts of the world. Once tests for compatibility of these systems to the WiMAX technology are complete, they will most likely be upgraded programmatically in compliance with the requirements of the final WiMAX standard.

In ideal, the wireless technology WiMAX based on industrial standards is developed to provide inexpensive high-speed communication for residential areas, enterprises, and mobile networks in cities and in rural areas. Note the definition - it contains a "niche" for the interaction of backbone WiMAX with the "local" Wi-Fi.

Outlooks for WiMAX in the nearest future

Today's WiMAX in the version IEEE 802.16-2004 is a standard of wireless communication, which provides broadband communication in the area of over 30 km in range with the bandwidth comparable to that for cable bonds - up to 10 Mbit/s and higher. The WiMAX technology allows operating in any conditions, including in the dense urban coverage, and providing a high quality of communications and data transmission rate.

The equipment of WiMAX networks operates in several frequency channels of 10 MHz width within the range from 2 GHz to 11 GHz. Certainly, the specific distribution of frequency ranges in various countries calls for the need to operate WiMAX in various sectors. Such a wide discrepancy of ranges has been selected to cover the specifics of most countries of the world. For instance, in the North America the WiMAX uses sectors in the 2.5 and 5 GHz ranges, in the Central and South America - 2.5, 3.5, and 5 GHz, in the Middle East , Africa, Western and Eastern Europe - 3.5 and 5 GHz, in the Asian Pacific region - 2.3, 3.5, and 5 GHz.

Essentially, WiMAX is a technology that provides access to Internet at T1 speed with the performance and coverage much higher than in modern Wi-Fi networks. In its turn, local Wi-Fi networks, various types of business and household cable/DSL networks of end users are just the continuation of WiMAX "backbone branches".

Establishing communications within 10 km range and farther, WiMAX points provide coverage of vast areas thus giving providers flexible enough conditions to ensure the very "last mile communication".

On the whole, the base characteristic of 802.16 standard provide a reach as far as 50 km, and coverage with the possible operation outside the direct visibility zone, which in prospect will give a peak data exchange rate up to 70 Mbit/s per sector, with the typical base station having up to coverage sectors.

Today, introduction of WiMAX is subdivided into the three main stages. The current first stage implies introduction and wide distribution of the WiMAX technology of EEE 802.16-2004 standard which came to replace the earlier versions IEEE 802.16a and 802.16d, and which uses external aerials of the "cellular disc" type aimed at consumers in fixed directions.

The second stage implies use of internal aerials, simplified and more flexible use of WiMAX to provide access.

The third stage promises a wide introduction of IEEE 802.16e specifications whose ratification is expected in early 2006, and the emergence of first networks expected in 2007. That means the possibility for operating WiMAX-Certified solutions even as part of portable devices moving across the certain "coverage area" of the network, in the image and likeness of modern cellular and Wi-Fi networks.

Development of such complex standards implies co-existence with other wireless standards, including cellular networks, development of new generations of "smart" aerials, application of new type of modulation like OFDMA, new types of services like QoS, data protection, and many other parameters. In this WiMAX review, we are not giving a detailed account of all the fine points of new standards, but in fact it is a long and painstaking process.

As regards the capabilities of the first-generation WiMAX - IEEE 802.16-2004, in ideal, each base station provides coverage within the range of up to 50 km at data exchange rate up to 35 Mbit/s. In practice, the width and respective performance of the channel is "sliced" for the end user by the service provider. But the way, the architecture of WiMAX networks which in ideal resembles honeycombs (but of a much larger "cell") implies placing antenna-feeder devices on high buildings, structures, and masts. No wonder that interest to the deployment of WiMAX networks was shown primarily by cellular network providers: however strong the competition between WiMAX and 3G/4G networks is, it is much cheaper to install and service several types of equipment on the same mast rather than on several ones. In any case, it is up to the consumer to decide whether to give preference to a specific network.

Today, maximum attention to the introduction of WiMAX networks is paid in the countries of vast territories and great distances from cities, as well as high percentage of rural population. Even for the most developed countries like Sweden it is of advantage to introduce WiMAX as an alternative to hard-wire backbone communications, GSM/EDGE and 3G networks. Needless to say, developing countries like China, India, and Russia will have to start from scratch.

WiMAX: wireless highway to the future

By: Vladimir Romanchenko

At first, there was the cable. No, that's wrong. First, there was the word, of course, and then the deed which resulted later in computers and other electronics - from super-clusters to mobiles. Then there rose the need for interaction among all this electronics. This is the way how the cable came into being, that is, first hard-wire interfaces. Then wireless, as technologies progressed. Leaving this long and sometimes heroic past of hard-wire networks outside the note, let's move on to the most interesting part - the current situation and the nearest future wireless prospects.

Separate Wi-Fi access points that could be plugged in to powerful backbone "hard-wire" networks, e.g. fiber-optical, were the first timid moves towards creation of wireless networks. Then there came up a new class of providers who deployed numerous commercial networks, thus in a matter of few years Wi-Fi networks turned into serious infrastructures - corporate and public. By now, many hotels, airports, and railway stations of the world have acquired Wi-Fi networks, and in some countries residential communities are covered this way.

No doubt, introduction of Wi-Fi wireless networks has proved a revolutionary solution to the "last mile" problem. However, the standard's original limitations for data exchange rate and range, number of channels, high cost of the infrastructure have not yet made it possible for Wi-Fi to become a total threat to cellular networks on the one hand, and hard-wire networks, on the other. Even despite the substantial advantages and introduction of new, more up-to-date versions of the standard, the "native limitations" of Wi-Fi will be eliminated only through new backbone standards for data exchange. Sort of WiMAX.

WiMAX Definition

WiMAX stands for Worldwide Interoperability for Microwave Access, and is a technology of broadband wireless communication standardized by the IEEE which complements DSL lines and cable technologies as an alternative solution to the "last mile" problem at great distances. The WiMAX technology can be used to implement broadband "last mile" connections, deployment of wireless access point, arrangement of high-speed communication among company branches and solution of other similar tasks.

Evolution of WiMAX

The preliminary version of WiMAX provided functionality with the equipment which was not subject to standard tests for compatibility to the WiMAX technology. A number of service providers are still using such preliminary hardware solutions to implement WiMAX pilot projects in many parts of the world. Once tests for compatibility of these systems to the WiMAX technology are complete, they will most likely be upgraded programmatically in compliance with the requirements of the final WiMAX standard.

In ideal, the wireless technology WiMAX based on industrial standards is developed to provide inexpensive high-speed communication for residential areas, enterprises, and mobile networks in cities and in rural areas. Note the definition - it contains a "niche" for the interaction of backbone WiMAX with the "local" Wi-Fi.

Outlooks for WiMAX in the nearest future

Today's WiMAX in the version IEEE 802.16-2004 is a standard of wireless communication, which provides broadband communication in the area of over 30 km in range with the bandwidth comparable to that for cable bonds - up to 10 Mbit/s and higher. The WiMAX technology allows operating in any conditions, including in the dense urban coverage, and providing a high quality of communications and data transmission rate.

The equipment of WiMAX networks operates in several frequency channels of 10 MHz width within the range from 2 GHz to 11 GHz. Certainly, the specific distribution of frequency ranges in various countries calls for the need to operate WiMAX in various sectors. Such a wide discrepancy of ranges has been selected to cover the specifics of most countries of the world. For instance, in the North America the WiMAX uses sectors in the 2.5 and 5 GHz ranges, in the Central and South America - 2.5, 3.5, and 5 GHz, in the Middle East , Africa, Western and Eastern Europe - 3.5 and 5 GHz, in the Asian Pacific region - 2.3, 3.5, and 5 GHz.

Essentially, WiMAX is a technology that provides access to Internet at T1 speed with the performance and coverage much higher than in modern Wi-Fi networks. In its turn, local Wi-Fi networks, various types of business and household cable/DSL networks of end users are just the continuation of WiMAX "backbone branches".

Establishing communications within 10 km range and farther, WiMAX points provide coverage of vast areas thus giving providers flexible enough conditions to ensure the very "last mile communication".

On the whole, the base characteristic of 802.16 standard provide a reach as far as 50 km, and coverage with the possible operation outside the direct visibility zone, which in prospect will give a peak data exchange rate up to 70 Mbit/s per sector, with the typical base station having up to coverage sectors.

Today, introduction of WiMAX is subdivided into the three main stages. The current first stage implies introduction and wide distribution of the WiMAX technology of EEE 802.16-2004 standard which came to replace the earlier versions IEEE 802.16a and 802.16d, and which uses external aerials of the "cellular disc" type aimed at consumers in fixed directions.

The second stage implies use of internal aerials, simplified and more flexible use of WiMAX to provide access.

The third stage promises a wide introduction of IEEE 802.16e specifications whose ratification is expected in early 2006, and the emergence of first networks expected in 2007. That means the possibility for operating WiMAX-Certified solutions even as part of portable devices moving across the certain "coverage area" of the network, in the image and likeness of modern cellular and Wi-Fi networks.

Development of such complex standards implies co-existence with other wireless standards, including cellular networks, development of new generations of "smart" aerials, application of new type of modulation like OFDMA, new types of services like QoS, data protection, and many other parameters. In this WiMAX review, we are not giving a detailed account of all the fine points of new standards, but in fact it is a long and painstaking process.

As regards the capabilities of the first-generation WiMAX - IEEE 802.16-2004, in ideal, each base station provides coverage within the range of up to 50 km at data exchange rate up to 35 Mbit/s. In practice, the width and respective performance of the channel is "sliced" for the end user by the service provider. But the way, the architecture of WiMAX networks which in ideal resembles honeycombs (but of a much larger "cell") implies placing antenna-feeder devices on high buildings, structures, and masts. No wonder that interest to the deployment of WiMAX networks was shown primarily by cellular network providers: however strong the competition between WiMAX and 3G/4G networks is, it is much cheaper to install and service several types of equipment on the same mast rather than on several ones. In any case, it is up to the consumer to decide whether to give preference to a specific network.

Today, maximum attention to the introduction of WiMAX networks is paid in the countries of vast territories and great distances from cities, as well as high percentage of rural population. Even for the most developed countries like Sweden it is of advantage to introduce WiMAX as an alternative to hard-wire backbone communications, GSM/EDGE and 3G networks. Needless to say, developing countries like China, India, and Russia will have to start from scratch.

WiMAX: wireless highway to the future

By: Vladimir Romanchenko

At first, there was the cable. No, that's wrong. First, there was the word, of course, and then the deed which resulted later in computers and other electronics - from super-clusters to mobiles. Then there rose the need for interaction among all this electronics. This is the way how the cable came into being, that is, first hard-wire interfaces. Then wireless, as technologies progressed. Leaving this long and sometimes heroic past of hard-wire networks outside the note, let's move on to the most interesting part - the current situation and the nearest future wireless prospects.

Separate Wi-Fi access points that could be plugged in to powerful backbone "hard-wire" networks, e.g. fiber-optical, were the first timid moves towards creation of wireless networks. Then there came up a new class of providers who deployed numerous commercial networks, thus in a matter of few years Wi-Fi networks turned into serious infrastructures - corporate and public. By now, many hotels, airports, and railway stations of the world have acquired Wi-Fi networks, and in some countries residential communities are covered this way.

No doubt, introduction of Wi-Fi wireless networks has proved a revolutionary solution to the "last mile" problem. However, the standard's original limitations for data exchange rate and range, number of channels, high cost of the infrastructure have not yet made it possible for Wi-Fi to become a total threat to cellular networks on the one hand, and hard-wire networks, on the other. Even despite the substantial advantages and introduction of new, more up-to-date versions of the standard, the "native limitations" of Wi-Fi will be eliminated only through new backbone standards for data exchange. Sort of WiMAX.

WiMAX Definition

WiMAX stands for Worldwide Interoperability for Microwave Access, and is a technology of broadband wireless communication standardized by the IEEE which complements DSL lines and cable technologies as an alternative solution to the "last mile" problem at great distances. The WiMAX technology can be used to implement broadband "last mile" connections, deployment of wireless access point, arrangement of high-speed communication among company branches and solution of other similar tasks.

Evolution of WiMAX

The preliminary version of WiMAX provided functionality with the equipment which was not subject to standard tests for compatibility to the WiMAX technology. A number of service providers are still using such preliminary hardware solutions to implement WiMAX pilot projects in many parts of the world. Once tests for compatibility of these systems to the WiMAX technology are complete, they will most likely be upgraded programmatically in compliance with the requirements of the final WiMAX standard.

In ideal, the wireless technology WiMAX based on industrial standards is developed to provide inexpensive high-speed communication for residential areas, enterprises, and mobile networks in cities and in rural areas. Note the definition - it contains a "niche" for the interaction of backbone WiMAX with the "local" Wi-Fi.

Outlooks for WiMAX in the nearest future

Today's WiMAX in the version IEEE 802.16-2004 is a standard of wireless communication, which provides broadband communication in the area of over 30 km in range with the bandwidth comparable to that for cable bonds - up to 10 Mbit/s and higher. The WiMAX technology allows operating in any conditions, including in the dense urban coverage, and providing a high quality of communications and data transmission rate.

The equipment of WiMAX networks operates in several frequency channels of 10 MHz width within the range from 2 GHz to 11 GHz. Certainly, the specific distribution of frequency ranges in various countries calls for the need to operate WiMAX in various sectors. Such a wide discrepancy of ranges has been selected to cover the specifics of most countries of the world. For instance, in the North America the WiMAX uses sectors in the 2.5 and 5 GHz ranges, in the Central and South America - 2.5, 3.5, and 5 GHz, in the Middle East , Africa, Western and Eastern Europe - 3.5 and 5 GHz, in the Asian Pacific region - 2.3, 3.5, and 5 GHz.

Essentially, WiMAX is a technology that provides access to Internet at T1 speed with the performance and coverage much higher than in modern Wi-Fi networks. In its turn, local Wi-Fi networks, various types of business and household cable/DSL networks of end users are just the continuation of WiMAX "backbone branches".

Establishing communications within 10 km range and farther, WiMAX points provide coverage of vast areas thus giving providers flexible enough conditions to ensure the very "last mile communication".

On the whole, the base characteristic of 802.16 standard provide a reach as far as 50 km, and coverage with the possible operation outside the direct visibility zone, which in prospect will give a peak data exchange rate up to 70 Mbit/s per sector, with the typical base station having up to coverage sectors.

Today, introduction of WiMAX is subdivided into the three main stages. The current first stage implies introduction and wide distribution of the WiMAX technology of EEE 802.16-2004 standard which came to replace the earlier versions IEEE 802.16a and 802.16d, and which uses external aerials of the "cellular disc" type aimed at consumers in fixed directions.

The second stage implies use of internal aerials, simplified and more flexible use of WiMAX to provide access.

The third stage promises a wide introduction of IEEE 802.16e specifications whose ratification is expected in early 2006, and the emergence of first networks expected in 2007. That means the possibility for operating WiMAX-Certified solutions even as part of portable devices moving across the certain "coverage area" of the network, in the image and likeness of modern cellular and Wi-Fi networks.

Development of such complex standards implies co-existence with other wireless standards, including cellular networks, development of new generations of "smart" aerials, application of new type of modulation like OFDMA, new types of services like QoS, data protection, and many other parameters. In this WiMAX review, we are not giving a detailed account of all the fine points of new standards, but in fact it is a long and painstaking process.

As regards the capabilities of the first-generation WiMAX - IEEE 802.16-2004, in ideal, each base station provides coverage within the range of up to 50 km at data exchange rate up to 35 Mbit/s. In practice, the width and respective performance of the channel is "sliced" for the end user by the service provider. But the way, the architecture of WiMAX networks which in ideal resembles honeycombs (but of a much larger "cell") implies placing antenna-feeder devices on high buildings, structures, and masts. No wonder that interest to the deployment of WiMAX networks was shown primarily by cellular network providers: however strong the competition between WiMAX and 3G/4G networks is, it is much cheaper to install and service several types of equipment on the same mast rather than on several ones. In any case, it is up to the consumer to decide whether to give preference to a specific network.

Today, maximum attention to the introduction of WiMAX networks is paid in the countries of vast territories and great distances from cities, as well as high percentage of rural population. Even for the most developed countries like Sweden it is of advantage to introduce WiMAX as an alternative to hard-wire backbone communications, GSM/EDGE and 3G networks. Needless to say, developing countries like China, India, and Russia will have to start from scratch.

More jobs cut as Alcatel-Lucent suffers through Q3

By Matt Kapko

Alcatel-Lucent lost more than $373 million during the past quarter the company reported as it announced it would be replacing its chief financial officer. Wall Street appeared relatively pleased with the results, which mostly fell in line with the company’s revised outlook. Alcatel-Lucent's stock was up nearly 3% to $9.67 after the news.

As the company cut around 1,000 jobs during the third quarter its revenues fell 7.8% from the year ago period. The recently combined company has cut more than 5,000 jobs since the beginning of the year and plans to achieve its targeted savings of $867 million through the cuts by year’s end.

“As you can see our results this quarter were essentially in line with the update we provided on Sept. 13, and in a few areas a bit better; however they are still not at a level that we are satisfied with,” CEO Pat Russo said in a statement.

Wireless revenues dipped at least 20% from the year-ago period.

“During the first nine months of operations as a single company, we strengthened our position in key strategic markets and technologies such as IP and mobile broadband required to position the company for long-term sustained growth. Having said that, and in spite of the promise of this industry and the long term benefits of the merger, we recognize that market conditions remain difficult, with continued pressure on revenues and margins due to intensified competition and some slowdown of spending in North America,” Russo added.

The company announced plans to further streamline the organization as it aims to cut costs by an additional $578 million by the end of 2009. Alcatel-Lucent said it will accelerate its ongoing job cuts with an additional 4,000 set to be out of a job by 2009.

“These are difficult but necessary decisions, and we will manage these reductions with care. With this plan, the company is targeting gross margins in the high 30’s and operating margins of 10% or better in the post integration phase beginning 2010,” Russo said.

The company also announced that Hubert de Pesquidoux would be replacing CFO Jean-Pascal Beaufret, who is leaving the company to pursue other opportunities.

More jobs cut as Alcatel-Lucent suffers through Q3

By Matt Kapko

Alcatel-Lucent lost more than $373 million during the past quarter the company reported as it announced it would be replacing its chief financial officer. Wall Street appeared relatively pleased with the results, which mostly fell in line with the company’s revised outlook. Alcatel-Lucent's stock was up nearly 3% to $9.67 after the news.

As the company cut around 1,000 jobs during the third quarter its revenues fell 7.8% from the year ago period. The recently combined company has cut more than 5,000 jobs since the beginning of the year and plans to achieve its targeted savings of $867 million through the cuts by year’s end.

“As you can see our results this quarter were essentially in line with the update we provided on Sept. 13, and in a few areas a bit better; however they are still not at a level that we are satisfied with,” CEO Pat Russo said in a statement.

Wireless revenues dipped at least 20% from the year-ago period.

“During the first nine months of operations as a single company, we strengthened our position in key strategic markets and technologies such as IP and mobile broadband required to position the company for long-term sustained growth. Having said that, and in spite of the promise of this industry and the long term benefits of the merger, we recognize that market conditions remain difficult, with continued pressure on revenues and margins due to intensified competition and some slowdown of spending in North America,” Russo added.

The company announced plans to further streamline the organization as it aims to cut costs by an additional $578 million by the end of 2009. Alcatel-Lucent said it will accelerate its ongoing job cuts with an additional 4,000 set to be out of a job by 2009.

“These are difficult but necessary decisions, and we will manage these reductions with care. With this plan, the company is targeting gross margins in the high 30’s and operating margins of 10% or better in the post integration phase beginning 2010,” Russo said.

The company also announced that Hubert de Pesquidoux would be replacing CFO Jean-Pascal Beaufret, who is leaving the company to pursue other opportunities.

More jobs cut as Alcatel-Lucent suffers through Q3

By Matt Kapko

Alcatel-Lucent lost more than $373 million during the past quarter the company reported as it announced it would be replacing its chief financial officer. Wall Street appeared relatively pleased with the results, which mostly fell in line with the company’s revised outlook. Alcatel-Lucent's stock was up nearly 3% to $9.67 after the news.

As the company cut around 1,000 jobs during the third quarter its revenues fell 7.8% from the year ago period. The recently combined company has cut more than 5,000 jobs since the beginning of the year and plans to achieve its targeted savings of $867 million through the cuts by year’s end.

“As you can see our results this quarter were essentially in line with the update we provided on Sept. 13, and in a few areas a bit better; however they are still not at a level that we are satisfied with,” CEO Pat Russo said in a statement.

Wireless revenues dipped at least 20% from the year-ago period.

“During the first nine months of operations as a single company, we strengthened our position in key strategic markets and technologies such as IP and mobile broadband required to position the company for long-term sustained growth. Having said that, and in spite of the promise of this industry and the long term benefits of the merger, we recognize that market conditions remain difficult, with continued pressure on revenues and margins due to intensified competition and some slowdown of spending in North America,” Russo added.

The company announced plans to further streamline the organization as it aims to cut costs by an additional $578 million by the end of 2009. Alcatel-Lucent said it will accelerate its ongoing job cuts with an additional 4,000 set to be out of a job by 2009.

“These are difficult but necessary decisions, and we will manage these reductions with care. With this plan, the company is targeting gross margins in the high 30’s and operating margins of 10% or better in the post integration phase beginning 2010,” Russo said.

The company also announced that Hubert de Pesquidoux would be replacing CFO Jean-Pascal Beaufret, who is leaving the company to pursue other opportunities.

Alcatel-Lucent shows off WiMAX handoff in Dominican Republic

By Matt Kapko

Alcatel-Lucent and Dominican Republic-based operator Onemax announced that they’ve completed the world’s first mobile handoffs on a commercial WiMAX 802.16e-2005 network in the 3.5 gigahertz spectrum band just one day after the companies officially launched the network.

Onemax executives, customers, local celebrities and government dignitaries were all on hand to view video telephony, high-definition streaming video, mobile broadband Internet access and Voice over Internet Protocl services in Santo Domingo, the nation’s capital. The services, which were supported with an IP Multimedia Subsystem (IMS) core, were delivered over the Onemax network to users traveling in a van.

“This achievement highlights the readiness of our network today, to offer a whole new range of compelling broadband services to residents of the Dominican Republic as well as visitors,” said Raoul Fontanez, Onemax’s CEO. “This collaboration with Alcatel-Lucent’s also is enabling us to give our customers and other distinguished guests a taste of some of the more advanced multimedia services that we will be able to introduce in the future.”

Onemax is the first service provider in the country to offer full nationwide wireless high-speed broadband Internet, multimedia and VoIP services, the company added. Alcatel-Lucent’s WiMAX Rev-e solution provides wireless broadband access in fixed, nomadic and mobile environments, the companies said.

“These achievements show that WiMAX is here today and poised to play an increasingly critical role in the delivery of mobile broadband services worldwide,” said Oliver Picard, president of Alcatel-Lucent’s activities in Europe and the South America.

Alcatel-Lucent shows off WiMAX handoff in Dominican Republic

By Matt Kapko

Alcatel-Lucent and Dominican Republic-based operator Onemax announced that they’ve completed the world’s first mobile handoffs on a commercial WiMAX 802.16e-2005 network in the 3.5 gigahertz spectrum band just one day after the companies officially launched the network.

Onemax executives, customers, local celebrities and government dignitaries were all on hand to view video telephony, high-definition streaming video, mobile broadband Internet access and Voice over Internet Protocl services in Santo Domingo, the nation’s capital. The services, which were supported with an IP Multimedia Subsystem (IMS) core, were delivered over the Onemax network to users traveling in a van.

“This achievement highlights the readiness of our network today, to offer a whole new range of compelling broadband services to residents of the Dominican Republic as well as visitors,” said Raoul Fontanez, Onemax’s CEO. “This collaboration with Alcatel-Lucent’s also is enabling us to give our customers and other distinguished guests a taste of some of the more advanced multimedia services that we will be able to introduce in the future.”

Onemax is the first service provider in the country to offer full nationwide wireless high-speed broadband Internet, multimedia and VoIP services, the company added. Alcatel-Lucent’s WiMAX Rev-e solution provides wireless broadband access in fixed, nomadic and mobile environments, the companies said.

“These achievements show that WiMAX is here today and poised to play an increasingly critical role in the delivery of mobile broadband services worldwide,” said Oliver Picard, president of Alcatel-Lucent’s activities in Europe and the South America.

Alcatel-Lucent shows off WiMAX handoff in Dominican Republic

By Matt Kapko

Alcatel-Lucent and Dominican Republic-based operator Onemax announced that they’ve completed the world’s first mobile handoffs on a commercial WiMAX 802.16e-2005 network in the 3.5 gigahertz spectrum band just one day after the companies officially launched the network.

Onemax executives, customers, local celebrities and government dignitaries were all on hand to view video telephony, high-definition streaming video, mobile broadband Internet access and Voice over Internet Protocl services in Santo Domingo, the nation’s capital. The services, which were supported with an IP Multimedia Subsystem (IMS) core, were delivered over the Onemax network to users traveling in a van.

“This achievement highlights the readiness of our network today, to offer a whole new range of compelling broadband services to residents of the Dominican Republic as well as visitors,” said Raoul Fontanez, Onemax’s CEO. “This collaboration with Alcatel-Lucent’s also is enabling us to give our customers and other distinguished guests a taste of some of the more advanced multimedia services that we will be able to introduce in the future.”

Onemax is the first service provider in the country to offer full nationwide wireless high-speed broadband Internet, multimedia and VoIP services, the company added. Alcatel-Lucent’s WiMAX Rev-e solution provides wireless broadband access in fixed, nomadic and mobile environments, the companies said.

“These achievements show that WiMAX is here today and poised to play an increasingly critical role in the delivery of mobile broadband services worldwide,” said Oliver Picard, president of Alcatel-Lucent’s activities in Europe and the South America.

Infrastructure awards wrap-up: Colubris, Nokia Siemens Networks, BelAir Networks and more

By Kristen Beckman

The following list details this week's infrastructure awards for the cellular, Wi-Fi, and WiMAX industries. The contracts are broken down by transmission technology, country and vendor. The value of the contract is included when available.

Wi-Fi

--France: Colubris Networks said it has been chosen by Alcatel-Lucent and French operator SFR to provide Wi-Fi equipment for a municipal Wi-Fi network in Paris.

Miscellaneous

--China: Nokia Siemens Networks said it won a convergent charging deal with Guangdong Telecom to provide its charge@once convergent online charging solution for prepaid and postpaid online charging for future mobile and data subscribers. Nokia Siemens Networks also announced a deal calling for it to enhance railway communications for the Hefei-Nanjing line with GSM-R technology.

--Europe: Deutsche Telekom awarded a contract to Nokia Siemens Networks for managed services and next-generation network modernization.

--United States: BelAir Networks said it has been selected by RedMoon Inc. to provide its wireless broadband mesh equipment to cover the town of Addison, Texas. Also in the United States, Cellular South awarded a contract to Alcatel-Lucent to upgrade the carrier’s network in Memphis and Jackson, Miss. The deal is valued at up to $55 million.

Infrastructure awards wrap-up: Colubris, Nokia Siemens Networks, BelAir Networks and more

By Kristen Beckman

The following list details this week's infrastructure awards for the cellular, Wi-Fi, and WiMAX industries. The contracts are broken down by transmission technology, country and vendor. The value of the contract is included when available.

Wi-Fi

--France: Colubris Networks said it has been chosen by Alcatel-Lucent and French operator SFR to provide Wi-Fi equipment for a municipal Wi-Fi network in Paris.

Miscellaneous

--China: Nokia Siemens Networks said it won a convergent charging deal with Guangdong Telecom to provide its charge@once convergent online charging solution for prepaid and postpaid online charging for future mobile and data subscribers. Nokia Siemens Networks also announced a deal calling for it to enhance railway communications for the Hefei-Nanjing line with GSM-R technology.

--Europe: Deutsche Telekom awarded a contract to Nokia Siemens Networks for managed services and next-generation network modernization.

--United States: BelAir Networks said it has been selected by RedMoon Inc. to provide its wireless broadband mesh equipment to cover the town of Addison, Texas. Also in the United States, Cellular South awarded a contract to Alcatel-Lucent to upgrade the carrier’s network in Memphis and Jackson, Miss. The deal is valued at up to $55 million.

Infrastructure awards wrap-up: Colubris, Nokia Siemens Networks, BelAir Networks and more

By Kristen Beckman

The following list details this week's infrastructure awards for the cellular, Wi-Fi, and WiMAX industries. The contracts are broken down by transmission technology, country and vendor. The value of the contract is included when available.

Wi-Fi

--France: Colubris Networks said it has been chosen by Alcatel-Lucent and French operator SFR to provide Wi-Fi equipment for a municipal Wi-Fi network in Paris.

Miscellaneous

--China: Nokia Siemens Networks said it won a convergent charging deal with Guangdong Telecom to provide its charge@once convergent online charging solution for prepaid and postpaid online charging for future mobile and data subscribers. Nokia Siemens Networks also announced a deal calling for it to enhance railway communications for the Hefei-Nanjing line with GSM-R technology.

--Europe: Deutsche Telekom awarded a contract to Nokia Siemens Networks for managed services and next-generation network modernization.

--United States: BelAir Networks said it has been selected by RedMoon Inc. to provide its wireless broadband mesh equipment to cover the town of Addison, Texas. Also in the United States, Cellular South awarded a contract to Alcatel-Lucent to upgrade the carrier’s network in Memphis and Jackson, Miss. The deal is valued at up to $55 million.

Designing Cableless Devices with the Bluetooth Specification

There is an overwhelming desire to clear up the clutter of too many wires at work and at home. Bluetooth is the technology that will enable this type of wireless communication. Before this wireless utopia can be achieved, many issues, including interoperability, must be addressed.

By BurkGehring and Stelios Koutroubinas


Bluetooth is an open global standard intended to replace all kinds of cables using short-range radio technology. Originally conceived by Ericsson, IBM, Intel, Nokia, and Toshiba to develop an open specification for short-range wireless connectivity between laptop computers and cellular telephones, the Bluetooth Special Interest Group (SIG) has expanded to over 1,000 members. Since the market for Bluetooth devices is estimated to be as large as $3 billion by 2005, many designers will be incorporating Bluetooth connectivity into their designs. 1

Bluetooth devices will replace RS-232, parallel, Universal Serial Bus (USB), and other types of cables with a single, standard wireless connection. Thus, any Bluetooth-certified device will be able to communicate with any other Bluetooth-certified device. For example, a Bluetooth-certified personal digital assistant (PDA) or cellular phone will work with any personal computer equipped with a Bluetooth-certified card.

The earliest applications are expected to include cable replacement for laptops, PDAs, mobile phones, and digital cameras, to name a few. Bluetooth supports voice as well as data transmission, so headsets used in the office or home could also become wireless.

Because Bluetooth is a global standard that uses a universally-available unlicensed portion of the radio frequency spectrum, Bluetooth-certified devices will interact in the same way in any part of the world.


How does it work?

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Any Bluetooth system has four basic parts: a radio (RF section) that receives and transmits data and voice; a baseband or link control unit that processes the transmitted or received data; link management software that manages the transmission; and supporting application software.


Bluetooth radio. The Bluetooth radio is a short-distance, low-power radio that operates in the unlicensed spectrum of 2.4 GHz, using a nominal antenna power of 0 dBm. At 0 dBm, the range is 10 meters, meaning equipment must be within 10 meters of each other (about 33 feet) to communicate using the Bluetooth standard. Optionally, a range of 100 meters (about 328 feet) may be achieved by using an antenna power of 20 dBm. Data is transmitted at a maximum gross rate of up to 1 Mbps. Communication protocol overhead limits the practical data rate to a little over 721 kbps. Interference or being out of range may increase the bit error rate (BER) and require packets to be re-sent, further decreasing the achievable data rate.

The 2.4-GHz frequency is shared by other types of equipment: microwave ovens; LANs; and industrial, security, and medical applications. As a result, interference with Bluetooth devices seems inevitable. The Bluetooth specification addresses this issue by employing frequency-hopping spread-spectrum techniques. Bluetooth uses seventy-nine hop frequencies spaced 1 MHz apart in the frequency range of 2.402 to 2.480 GHz. The hop rate is 1,600 hops per second (625-�s dwell time, at each frequency). If the transmission encounters interference, it waits for the next frequency hop and re-transmits on a new frequency.


Baseband . In wireless communications, the baseband is the hardware that turns received radio signals into a digital form, which can be processed by the host application. It also converts digital or voice data into a form that can be transmitted using a radio signal.

Each packet contains information about where it is coming from, what frequency it is using, and where it is going. Packets also contain information on how the data was compressed, the order in which the packets were transmitted, and information used to verify the effectiveness of the transmission. When the data is received it is checked for accuracy, extracted from the packet, reassembled, decompressed, and possibly filtered.

The baseband processor handles all the tasks just described. It takes care of converting data from one form to another (such as from voice to digital data), compressing it, putting it into packets, taking it out of packets, assigning identifiers and error correction information, and then reversing the entire process for data that is received. In Bluetooth, the baseband function is called the link controller.


Links. The Bluetooth link is the method of data transmission to be used. The Bluetooth standard supports two link types – synchronous connection-oriented (SCO) links, used primarily for voice communications, and asynchronous connectionless (ACL) links for packet data. Each link type supports sixteen different packet types that are used, depending on the application. Any two devices in a Bluetooth system may use either link type and may change link types during a transmission.


Link management. The link manager software runs on a microprocessor and manages the communication between Bluetooth devices. Each Bluetooth device has its own link manager, which discovers other remote link managers, and communicates with them to handle link setup, negotiate features, authenticate QoS, and to encrypt and adjust data rate on link, dynamically.


Link controller. The link controller is a supervisory function that handles all of the Bluetooth baseband functions and supports the link manager. It sends and receives data, identifies the sending device, performs authentication and ciphering functions, determines what type of frame to use on a slot-by-slot basis, directs how devices will listen for transmissions from other devices, or puts devices into various power-save modes according to Bluetooth-specified procedures. Each packet uses a single 625-�s timeslot, but can be extended to cover up to five slots. Bluetooth supports an asynchronous data channel, three synchronous voice channels at 64 kbps, or simultaneous asynchronous data and synchronous voice channels. The asynchronous channel can support an asymmetric link of 721 kbps in either direction and 57.6 kbps in the return direction, or a 432.6-kbps symmetric link.


Application software. The application software is embedded in the device that operates an application over the Bluetooth protocol stack. This software allows the PDA, mobile phone, or keyboard to do its job. All Bluetooth devices must have compatible sections in their Bluetooth stack, so that all Bluetooth devices will be able to interoperate with each other.

All Bluetooth-certified devices must have the components described above, to be in accordance with the Bluetooth standard. The standard and certification procedures guarantee global interoperability between devices.



Designing Bluetooth applications

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All Bluetooth designs require a transceiver and a baseband controller that meet the Bluetooth specification. An antenna and a microcontroller (MCU) to run the link control, link manager, and host controller interface (HCI) and/or logical link control and adaptation protocol (L2CAP) firmware are also needed. Alternatively, developers can choose to implement protocols up to, and including, HCI on the microcontroller, and to implement a counterpart of HCI (the HCI driver) and L2CAP on a machine that hosts the Bluetooth chip-set (such as a PC or a second microcontroller on the same or attached printed circuit board).

Quite a few choices for the Bluetooth hardware are available. Several vendors plan to offer Bluetooth baseband ICs, transceiver ICs, or both. Others are offering integrated solutions that include the baseband, radio, microcontroller, and memory. The Bluetooth SIG has a target for a fully-integrated Bluetooth solution priced at $5 or less by the year 2001. In this type of solution, developing the firmware and meeting timing constraints will be a major challenge.



Processor selection

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The Bluetooth baseband has rigorous timing requirements, so the chosen processor must be able to deliver sufficient throughput, consume minimal power, and be cost effective. One of the key design issues is whether to use dedicated hardware for the link controller or to implement link control in the chipset's microcontroller. The Bluetooth spec follows little endian convention, so the microcontroller should also support little endian operation. Since the microcontroller should be able to handle multibyte vectors, a 32-bit device is preferable. This is particularly true if security features are to be implemented. The MCU compiler will have to provide dense and highly-optimized object code because program space and/or timing requirements are critical.


Baseband timing constraints

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The granularity of the processing in the baseband layer will need to be one-half of a Bluetooth slot (312.5 �s) because some access procedures produce two packets per slot and because FHSS inquiry response packets may start at a half-slot boundary.

The transceiver is heavily restricted by Tvco and Tpower_up. Although there are procedures that the firmware can execute during Tvco and Tpower_up, it is vital that the firmware has decided what should be done with the next slot in the time duration 321.5 �s minus all the previously-described time periods (Tvco+Tpower_up+ Tuncertainty_window+Taccess_code). Thus, the link control functionality should be implemented as a finite-state machine that runs in interrupt mode, and the execution of the link control code should be synchronized with the slot boundaries.



Hardware/software partitioning

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Due to the rigid timing constraints on the Bluetooth baseband, designers should consider replacing some of the Bluetooth firmware blocks with dedicated hardware. This is particularly true for time-consuming and/or time-critical procedures such as LSFRs (header error correction, forward error correction [FEC], cyclical redundancy check, data whitening, and testing the bit sequence). Each packet type and each packet field requires different bit transformations (such as FEC or data whitening). By implementing these functions in the hardware, the packet type and current field can be traced during receive/transmit to quickly decide which transformations should be enabled or disabled.

Additional baseband functions which can be implemented in the hardware include low-level security functions such as cipher stream generation and authentication SAFER algorithms. Implementing these tasks in the hardware relieves the MCU of having to perform them, thereby speeding up firmware execution. It also reduces the required amount of system SRAM and Flash memory. Using an off-the-shelf RTOS that supports the multithreading and scheduling requirements of the Bluetooth specification is another option. The RTOS should be able to implement context switching and service interrupts quickly, in order to meet the Tfirmware constraints, and should also have an acceptable memory footprint – especially for a fully-integrated Bluetooth solution.



Bluetooth Radio

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Several members of the Bluetooth SIG are developing single-chip Bluetooth radios. The Bluetooth standard requires a receive sensitivity of -70 dBm, so any Bluetooth certified radio will have been tested to meet this standard. However, increasing the receive sensitivity gives the designer the freedom to implement designs that have a longer range than the 10 meters in the Bluetooth specification. At -80 dBm, the Bluetooth application could have a range of 100 meters, an advantage that could be extremely useful in some applications. Since the BER is largely dependent on the maximum distance between the two Bluetooth devices, a transceiver IC with a higher rating will also have a smaller BER, which allows the Bluetooth device to achieve a higher data rate.

GSM phones have a maximum output power in the range of 1 to 3W, and receive and transmit frequencies ranging from 890 to 1,990 MHz, while Bluetooth transceivers are designed to work with signals as low as 10pW. Noise from the phone's transmitter may interfere with the Bluetooth signal. A trap can be placed at the output of the transmitter to attenuate any energy radiated in the 2.4 GHz band.

In most RF systems the transmit data modulates the VCO by switching the charge pump in tri-state while the phase-locked loop (PLL) is in open-loop mode. This causes frequency drift that can result in transmission errors. Frequency drift can be controlled by using I&Q modulation in which I&Q signals are transmitted by the baseband to the RF section during the mixer stage to stabilize the frequency. This requires additional firmware in the baseband, as well as off-chip passive filters. Another approach is to use a modulation compensation circuit (MCC) that keeps the VCO frequency stable while the PLL is in closed-loop mode. This latter approach to demodulation eliminates the need for any external filters. It also allows the collocation of several time slots, increasing the effective data rate. Since closed-loop modulation is insensitive to tolerances and noise influences, it results in better performance.

All superheterodyne radios tend to receive two frequencies – the signal frequency and the image frequency. An unwanted signal at the image frequency must be suppressed to avoid interference with the desired signal. One means of doing this is to use an off-chip passive filter. The external filter will increase system size and add cost, which are drawbacks in portable applications. Another approach is to include the image rejection as part of the mixer on the transceiver. The image rejection mixer converts the frequency down to 111 MHz, a frequency that conserves power and for which many low-cost filters are available.



Power consumption

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Virtually all Bluetooth applications will be battery operated, making power consumption a significant consideration. Implementing some of the baseband functions in hardware allows the MCU clock to be slowed, reducing power drain. Gating the clock to the MCU and the other hardware blocks also helps to minimize power consumption. Processing power varies with time, so it is preferable to drive the MCU with a relatively high-speed clock and to gate the MCU clock when the Bluetooth subsystem is in sleep mode. Using the image rejection mixer to convert the frequency down to 111 MHz, as previously described, also conserves power.

Firmware considerations – HCI

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The HCI protocol structure is described quite clearly in the Bluetooth specification. However, from an implementation point of view, the boundaries between HCI, link manager (LM), and link controller (LC) are not clear from the beginning. So, these layers should be designed carefully and, if possible, developed in parallel in order to integrate the system data structures as much as possible and to avoid data and code redundancy.

The HCI packet structures (Command, Event, ACL, and SCO packets) must be wrapped with additional information relating to the transport layer above HCI that runs on top of the physical link between the Bluetooth device and its host. The dataflow infrastructure must be carefully developed because individual HCI commands do not require the same amount of processing, nor do they remain in the system memory for the same duration. For example, processing the command Read_Local_Version_Information is straightforward when compared to processing the command Create_Connection.


Firmware considerations – L2CAP

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L2CAP is used for protocol multiplexing above the basic Bluetooth layers, for packet segmentation and reassembly, and to convey QoS information. The system designer must first decide whether to embed L2CAP with the rest of the layers or have it running as part of the host OS. Making this decision depends on the usage model and the device that will contain the Bluetooth design. A mobile phone will have to maintain L2CAP in an embedded nonvolatile memory, while a laptop computer will not.

If L2CAP is to be embedded, the designer must take into account the amount of information the Bluetooth subsystem can hold in its receive buffers on the host side before it can fragment them into smaller chunks according to Bluetooth packet sizes. The maximum packet size that L2CAP accepts from a protocol running on top of it is 64 kbytes.

Although the Bluetooth standard specifies which transport layers a Bluetooth device can use to communicate with the host to exchange HCI packets over various physical links (UART, USB), it does not specify any of them for an embedded L2CAP over the same links. Designers will have to consider how this interface is to be realized. If L2CAP is built on the host side, there is always a problem of integrating this layer into the host's OS in a way that ensures protocol multiplexing can take place above it with minimal alterations to the host's driver stack. A host-side L2CAP also poses the problem of interfacing the lower part of the L2CAP with a host-side HCI driver or with another proprietary driver. In the first case, the stack may run slower. In the second case, more programming effort will be needed to achieve interoperability requirements.

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Stelios Koutroubinas is managing director, vice president, and CEO of the board of directors of Atmel Hellas S.A. He holds an engineering degree and a PhD in electrical engineering from the University of Patras, Patras, Greece. He can be reached at steliosk@atmel.gr .

Burkhard Gehring is the technical project leader for Temic Semiconductor's Bluetooth radio IC group. He received the Diplom Ingenieur degree from the Technical University of Dresden, Germany. He can be reached at burkhard.gehring@temic_semi.com

Designing Cableless Devices with the Bluetooth Specification

There is an overwhelming desire to clear up the clutter of too many wires at work and at home. Bluetooth is the technology that will enable this type of wireless communication. Before this wireless utopia can be achieved, many issues, including interoperability, must be addressed.

By BurkGehring and Stelios Koutroubinas


Bluetooth is an open global standard intended to replace all kinds of cables using short-range radio technology. Originally conceived by Ericsson, IBM, Intel, Nokia, and Toshiba to develop an open specification for short-range wireless connectivity between laptop computers and cellular telephones, the Bluetooth Special Interest Group (SIG) has expanded to over 1,000 members. Since the market for Bluetooth devices is estimated to be as large as $3 billion by 2005, many designers will be incorporating Bluetooth connectivity into their designs. 1

Bluetooth devices will replace RS-232, parallel, Universal Serial Bus (USB), and other types of cables with a single, standard wireless connection. Thus, any Bluetooth-certified device will be able to communicate with any other Bluetooth-certified device. For example, a Bluetooth-certified personal digital assistant (PDA) or cellular phone will work with any personal computer equipped with a Bluetooth-certified card.

The earliest applications are expected to include cable replacement for laptops, PDAs, mobile phones, and digital cameras, to name a few. Bluetooth supports voice as well as data transmission, so headsets used in the office or home could also become wireless.

Because Bluetooth is a global standard that uses a universally-available unlicensed portion of the radio frequency spectrum, Bluetooth-certified devices will interact in the same way in any part of the world.


How does it work?

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Any Bluetooth system has four basic parts: a radio (RF section) that receives and transmits data and voice; a baseband or link control unit that processes the transmitted or received data; link management software that manages the transmission; and supporting application software.


Bluetooth radio. The Bluetooth radio is a short-distance, low-power radio that operates in the unlicensed spectrum of 2.4 GHz, using a nominal antenna power of 0 dBm. At 0 dBm, the range is 10 meters, meaning equipment must be within 10 meters of each other (about 33 feet) to communicate using the Bluetooth standard. Optionally, a range of 100 meters (about 328 feet) may be achieved by using an antenna power of 20 dBm. Data is transmitted at a maximum gross rate of up to 1 Mbps. Communication protocol overhead limits the practical data rate to a little over 721 kbps. Interference or being out of range may increase the bit error rate (BER) and require packets to be re-sent, further decreasing the achievable data rate.

The 2.4-GHz frequency is shared by other types of equipment: microwave ovens; LANs; and industrial, security, and medical applications. As a result, interference with Bluetooth devices seems inevitable. The Bluetooth specification addresses this issue by employing frequency-hopping spread-spectrum techniques. Bluetooth uses seventy-nine hop frequencies spaced 1 MHz apart in the frequency range of 2.402 to 2.480 GHz. The hop rate is 1,600 hops per second (625-�s dwell time, at each frequency). If the transmission encounters interference, it waits for the next frequency hop and re-transmits on a new frequency.


Baseband . In wireless communications, the baseband is the hardware that turns received radio signals into a digital form, which can be processed by the host application. It also converts digital or voice data into a form that can be transmitted using a radio signal.

Each packet contains information about where it is coming from, what frequency it is using, and where it is going. Packets also contain information on how the data was compressed, the order in which the packets were transmitted, and information used to verify the effectiveness of the transmission. When the data is received it is checked for accuracy, extracted from the packet, reassembled, decompressed, and possibly filtered.

The baseband processor handles all the tasks just described. It takes care of converting data from one form to another (such as from voice to digital data), compressing it, putting it into packets, taking it out of packets, assigning identifiers and error correction information, and then reversing the entire process for data that is received. In Bluetooth, the baseband function is called the link controller.


Links. The Bluetooth link is the method of data transmission to be used. The Bluetooth standard supports two link types – synchronous connection-oriented (SCO) links, used primarily for voice communications, and asynchronous connectionless (ACL) links for packet data. Each link type supports sixteen different packet types that are used, depending on the application. Any two devices in a Bluetooth system may use either link type and may change link types during a transmission.


Link management. The link manager software runs on a microprocessor and manages the communication between Bluetooth devices. Each Bluetooth device has its own link manager, which discovers other remote link managers, and communicates with them to handle link setup, negotiate features, authenticate QoS, and to encrypt and adjust data rate on link, dynamically.


Link controller. The link controller is a supervisory function that handles all of the Bluetooth baseband functions and supports the link manager. It sends and receives data, identifies the sending device, performs authentication and ciphering functions, determines what type of frame to use on a slot-by-slot basis, directs how devices will listen for transmissions from other devices, or puts devices into various power-save modes according to Bluetooth-specified procedures. Each packet uses a single 625-�s timeslot, but can be extended to cover up to five slots. Bluetooth supports an asynchronous data channel, three synchronous voice channels at 64 kbps, or simultaneous asynchronous data and synchronous voice channels. The asynchronous channel can support an asymmetric link of 721 kbps in either direction and 57.6 kbps in the return direction, or a 432.6-kbps symmetric link.


Application software. The application software is embedded in the device that operates an application over the Bluetooth protocol stack. This software allows the PDA, mobile phone, or keyboard to do its job. All Bluetooth devices must have compatible sections in their Bluetooth stack, so that all Bluetooth devices will be able to interoperate with each other.

All Bluetooth-certified devices must have the components described above, to be in accordance with the Bluetooth standard. The standard and certification procedures guarantee global interoperability between devices.



Designing Bluetooth applications

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All Bluetooth designs require a transceiver and a baseband controller that meet the Bluetooth specification. An antenna and a microcontroller (MCU) to run the link control, link manager, and host controller interface (HCI) and/or logical link control and adaptation protocol (L2CAP) firmware are also needed. Alternatively, developers can choose to implement protocols up to, and including, HCI on the microcontroller, and to implement a counterpart of HCI (the HCI driver) and L2CAP on a machine that hosts the Bluetooth chip-set (such as a PC or a second microcontroller on the same or attached printed circuit board).

Quite a few choices for the Bluetooth hardware are available. Several vendors plan to offer Bluetooth baseband ICs, transceiver ICs, or both. Others are offering integrated solutions that include the baseband, radio, microcontroller, and memory. The Bluetooth SIG has a target for a fully-integrated Bluetooth solution priced at $5 or less by the year 2001. In this type of solution, developing the firmware and meeting timing constraints will be a major challenge.



Processor selection

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The Bluetooth baseband has rigorous timing requirements, so the chosen processor must be able to deliver sufficient throughput, consume minimal power, and be cost effective. One of the key design issues is whether to use dedicated hardware for the link controller or to implement link control in the chipset's microcontroller. The Bluetooth spec follows little endian convention, so the microcontroller should also support little endian operation. Since the microcontroller should be able to handle multibyte vectors, a 32-bit device is preferable. This is particularly true if security features are to be implemented. The MCU compiler will have to provide dense and highly-optimized object code because program space and/or timing requirements are critical.


Baseband timing constraints

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The granularity of the processing in the baseband layer will need to be one-half of a Bluetooth slot (312.5 �s) because some access procedures produce two packets per slot and because FHSS inquiry response packets may start at a half-slot boundary.

The transceiver is heavily restricted by Tvco and Tpower_up. Although there are procedures that the firmware can execute during Tvco and Tpower_up, it is vital that the firmware has decided what should be done with the next slot in the time duration 321.5 �s minus all the previously-described time periods (Tvco+Tpower_up+ Tuncertainty_window+Taccess_code). Thus, the link control functionality should be implemented as a finite-state machine that runs in interrupt mode, and the execution of the link control code should be synchronized with the slot boundaries.



Hardware/software partitioning

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Due to the rigid timing constraints on the Bluetooth baseband, designers should consider replacing some of the Bluetooth firmware blocks with dedicated hardware. This is particularly true for time-consuming and/or time-critical procedures such as LSFRs (header error correction, forward error correction [FEC], cyclical redundancy check, data whitening, and testing the bit sequence). Each packet type and each packet field requires different bit transformations (such as FEC or data whitening). By implementing these functions in the hardware, the packet type and current field can be traced during receive/transmit to quickly decide which transformations should be enabled or disabled.

Additional baseband functions which can be implemented in the hardware include low-level security functions such as cipher stream generation and authentication SAFER algorithms. Implementing these tasks in the hardware relieves the MCU of having to perform them, thereby speeding up firmware execution. It also reduces the required amount of system SRAM and Flash memory. Using an off-the-shelf RTOS that supports the multithreading and scheduling requirements of the Bluetooth specification is another option. The RTOS should be able to implement context switching and service interrupts quickly, in order to meet the Tfirmware constraints, and should also have an acceptable memory footprint – especially for a fully-integrated Bluetooth solution.



Bluetooth Radio

--------------------------------------------------------------------------------

Several members of the Bluetooth SIG are developing single-chip Bluetooth radios. The Bluetooth standard requires a receive sensitivity of -70 dBm, so any Bluetooth certified radio will have been tested to meet this standard. However, increasing the receive sensitivity gives the designer the freedom to implement designs that have a longer range than the 10 meters in the Bluetooth specification. At -80 dBm, the Bluetooth application could have a range of 100 meters, an advantage that could be extremely useful in some applications. Since the BER is largely dependent on the maximum distance between the two Bluetooth devices, a transceiver IC with a higher rating will also have a smaller BER, which allows the Bluetooth device to achieve a higher data rate.

GSM phones have a maximum output power in the range of 1 to 3W, and receive and transmit frequencies ranging from 890 to 1,990 MHz, while Bluetooth transceivers are designed to work with signals as low as 10pW. Noise from the phone's transmitter may interfere with the Bluetooth signal. A trap can be placed at the output of the transmitter to attenuate any energy radiated in the 2.4 GHz band.

In most RF systems the transmit data modulates the VCO by switching the charge pump in tri-state while the phase-locked loop (PLL) is in open-loop mode. This causes frequency drift that can result in transmission errors. Frequency drift can be controlled by using I&Q modulation in which I&Q signals are transmitted by the baseband to the RF section during the mixer stage to stabilize the frequency. This requires additional firmware in the baseband, as well as off-chip passive filters. Another approach is to use a modulation compensation circuit (MCC) that keeps the VCO frequency stable while the PLL is in closed-loop mode. This latter approach to demodulation eliminates the need for any external filters. It also allows the collocation of several time slots, increasing the effective data rate. Since closed-loop modulation is insensitive to tolerances and noise influences, it results in better performance.

All superheterodyne radios tend to receive two frequencies – the signal frequency and the image frequency. An unwanted signal at the image frequency must be suppressed to avoid interference with the desired signal. One means of doing this is to use an off-chip passive filter. The external filter will increase system size and add cost, which are drawbacks in portable applications. Another approach is to include the image rejection as part of the mixer on the transceiver. The image rejection mixer converts the frequency down to 111 MHz, a frequency that conserves power and for which many low-cost filters are available.



Power consumption

--------------------------------------------------------------------------------

Virtually all Bluetooth applications will be battery operated, making power consumption a significant consideration. Implementing some of the baseband functions in hardware allows the MCU clock to be slowed, reducing power drain. Gating the clock to the MCU and the other hardware blocks also helps to minimize power consumption. Processing power varies with time, so it is preferable to drive the MCU with a relatively high-speed clock and to gate the MCU clock when the Bluetooth subsystem is in sleep mode. Using the image rejection mixer to convert the frequency down to 111 MHz, as previously described, also conserves power.

Firmware considerations – HCI

--------------------------------------------------------------------------------

The HCI protocol structure is described quite clearly in the Bluetooth specification. However, from an implementation point of view, the boundaries between HCI, link manager (LM), and link controller (LC) are not clear from the beginning. So, these layers should be designed carefully and, if possible, developed in parallel in order to integrate the system data structures as much as possible and to avoid data and code redundancy.

The HCI packet structures (Command, Event, ACL, and SCO packets) must be wrapped with additional information relating to the transport layer above HCI that runs on top of the physical link between the Bluetooth device and its host. The dataflow infrastructure must be carefully developed because individual HCI commands do not require the same amount of processing, nor do they remain in the system memory for the same duration. For example, processing the command Read_Local_Version_Information is straightforward when compared to processing the command Create_Connection.


Firmware considerations – L2CAP

--------------------------------------------------------------------------------

L2CAP is used for protocol multiplexing above the basic Bluetooth layers, for packet segmentation and reassembly, and to convey QoS information. The system designer must first decide whether to embed L2CAP with the rest of the layers or have it running as part of the host OS. Making this decision depends on the usage model and the device that will contain the Bluetooth design. A mobile phone will have to maintain L2CAP in an embedded nonvolatile memory, while a laptop computer will not.

If L2CAP is to be embedded, the designer must take into account the amount of information the Bluetooth subsystem can hold in its receive buffers on the host side before it can fragment them into smaller chunks according to Bluetooth packet sizes. The maximum packet size that L2CAP accepts from a protocol running on top of it is 64 kbytes.

Although the Bluetooth standard specifies which transport layers a Bluetooth device can use to communicate with the host to exchange HCI packets over various physical links (UART, USB), it does not specify any of them for an embedded L2CAP over the same links. Designers will have to consider how this interface is to be realized. If L2CAP is built on the host side, there is always a problem of integrating this layer into the host's OS in a way that ensures protocol multiplexing can take place above it with minimal alterations to the host's driver stack. A host-side L2CAP also poses the problem of interfacing the lower part of the L2CAP with a host-side HCI driver or with another proprietary driver. In the first case, the stack may run slower. In the second case, more programming effort will be needed to achieve interoperability requirements.

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Stelios Koutroubinas is managing director, vice president, and CEO of the board of directors of Atmel Hellas S.A. He holds an engineering degree and a PhD in electrical engineering from the University of Patras, Patras, Greece. He can be reached at steliosk@atmel.gr .

Burkhard Gehring is the technical project leader for Temic Semiconductor's Bluetooth radio IC group. He received the Diplom Ingenieur degree from the Technical University of Dresden, Germany. He can be reached at burkhard.gehring@temic_semi.com