Marc Engels

Wireless Local Area Networks (WLANs) are experiencing a growing importance recently. Whereas WLANs were primarily used for niche applications in the past, they are now deployed as wireless extensions to computer networks. The increase of the datarates from 2 Mbps up to 11 Mbps for roughly a constant price has played a major role in this breakthrough. As a consequence, an even greater success can be envisioned for the more recent OFDM-based WLAN standards in the 5 GHz band that offer up to 54 Mbps. At IMEC we have realized this potential already several years ago and have established a successful research program on OFDM-based WLAN. The program resulted in an operational prototype of a 5 GHz OFDM system. The longer term goals of this program are to extend the indoor range of the WLAN systems up to 100 m and to increase the capacity above 100 Mbps. Driven by these goals, Patrick embarked on the usage of multiple antenna techniques and, more in particular, Space Division Multiple Access (SDMA) for WLAN as the topic for his doctoral research. During this research, key contributions were made towards making SDMA for WLAN a reality. To name a few: A basic scheme for combining OFDM and SDMA was proposed. Also realistic non-linear detection methods were developed. These me- ods achieve a high implementation efficiency, by exploiting the p- allelism of the data model and the frequency-selectivity of the pr- agation channel.

Broadband Fixed Wireless Access provides a systematic overview of the emerging WiMAX technology, and much of the material is based on the practical experiences of the authors in building new systems. This material will be of significant interest to network architects and developers of broadband fixed wireless access products. With the advent of the IEEE 802.16 standard (has the standard or any part of it been adopted or is likely to be adopted soon?) and next generation equipment, this technology has been growing in interest. The authors discuss applications at microwave frequencies between 2 and 11 GHz that could be attractive options for operators without an existing access infrastructure for reaching end users. This introductory volume demystifies the technology and provides technical exposure to the various system trade-offs. Additionally, the book features the following highlights: - Detailed modeling of broadband fixed wireless access propagation channel, including new measurements for its time variation - An extensive overview of the IEEE 802.16 standard - A tutorial on implementation challenges for WiMAX terminals - Discussion of the suitability of various multi-antenna techniques - Elaboration of various techniques, i.e. autodirecting antennas, bridging with WLAN, and multi-hop networking, that can be used to reduce the cost of ownership of a WiMAX network for an operator The authors cover a wide range of topics, from network deployment to implementation of terminals. Wireless professionals will gain a head start from the information on WiMAX technology. This is a must read book when starting with broadband fixed wireless access.

Broadband Fixed Wireless Access provides a systematic overview of the emerging WiMAX technology, and much of the material is based on the practical experiences of the authors in building new systems. This material will be of significant interest to network architects and developers of broadband fixed wireless access products. With the advent of the IEEE 802.16 standard (has the standard or any part of it been adopted or is likely to be adopted soon?) and next generation equipment, this technology has been growing in interest. The authors discuss applications at microwave frequencies between 2 and 11 GHz that could be attractive options for operators without an existing access infrastructure for reaching end users. This introductory volume demystifies the technology and provides technical exposure to the various system trade-offs. Additionally, the book features the following highlights: - Detailed modeling of broadband fixed wireless access propagation channel, including new measurements for its time variation - An extensive overview of the IEEE 802.16 standard - A tutorial on implementation challenges for WiMAX terminals - Discussion of the suitability of various multi-antenna techniques - Elaboration of various techniques, i.e. autodirecting antennas, bridging with WLAN, and multi-hop networking, that can be used to reduce the cost of ownership of a WiMAX network for an operator The authors cover a wide range of topics, from network deployment to implementation of terminals. Wireless professionals will gain a head start from the information on WiMAX technology. This is a must read book when starting with broadband fixed wireless access.

Wireless Local Area Networks (WLANs) are experiencing a growing importance recently. Whereas WLANs were primarily used for niche applications in the past, they are now deployed as wireless extensions to computer networks. The increase of the datarates from 2 Mbps up to 11 Mbps for roughly a constant price has played a major role in this breakthrough. As a consequence, an even greater success can be envisioned for the more recent OFDM-based WLAN standards in the 5 GHz band that offer up to 54 Mbps. At IMEC we have realized this potential already several years ago and have established a successful research program on OFDM-based WLAN. The program resulted in an operational prototype of a 5 GHz OFDM system. The longer term goals of this program are to extend the indoor range of the WLAN systems up to 100 m and to increase the capacity above 100 Mbps. Driven by these goals, Patrick embarked on the usage of multiple antenna techniques and, more in particular, Space Division Multiple Access (SDMA) for WLAN as the topic for his doctoral research. During this research, key contributions were made towards making SDMA for WLAN a reality. To name a few: A basic scheme for combining OFDM and SDMA was proposed. Also realistic non-linear detection methods were developed. These me- ods achieve a high implementation efficiency, by exploiting the p- allelism of the data model and the frequency-selectivity of the pr- agation channel.