Author:

Abstract:

Wireless communications, mainly through GSM/UMTS, has undergone a spectacular growth in the last decade. Wireless broadband communications, to achieve comparable penetration in indoor environments, will have to offer the same performance as it's wired counterpart, at a reasonable price. The research initiated by IMEC relies on this statement and, in two to three years from now, will enable the development of a 155 Mb/s indoor communication system based on multi-carrier modulation (Orthogonal Frequency Division Modulation: OFDM). This research has already given birth to a dedicated ASIC implementing an OFDM modem with 64 carriers that allows transmission of complex symbols (QPSK, 16-QAM, 64-QAM) at 72Mbits/s. While these systems are now also becoming industry standards, we are already working on the next generation systems. Thereto, we devote ourselves to break the capacity-complexity bottlenecks even further. Our research in this area is primarily concentrating on turbo-decoding (which allows operation c lose to the Shannon limit), on link adaptation (which allows optimization of instantaneous throughput), and on Spatial Division Multiple Access (SDMA: which uses multiple antennas at the base station and/or at the terminal to multiply the capacity).