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0002 The current generation of high data rate wireless local area network (WLAN) standards, such as Hiperlan/2 and IEEE802. 11a, provide data rates of up to 54 Mbit/s. However, the ever-increasing demand for even higher data rate services. Such as Internet, video and multi-media, have created a need for improved bandwidth efficiency from next generation wireless LANs. The current IEEE802. 11a stan dard employs the bandwidth efficient scheme of Orthogonal Frequency Division Multiplex (OFDM) and adaptive modu lation and demodulation. The systems were designed as single-input single-output (SISO) systems, essentially employing a single transit and receive antenna at each end of the link. However within ETSI BRAN some provision for multiple antennas or sectorised antennas has been investi gated for improved diversity gain and thus link robustness.

0003 Hiperlan/2 is a European standard for a 54 …