Center for Pervasive Communications and Computing

In this paper we describe a coding, modulation, and spatial processing technique for fixed broadband wireless Internet access applications and provide examples of its performance. This technique is built on Orthogonal Frequency Division Multiplexing (OFDM) and is known as Vector OFDM (VOFDM). We compare VOFDM with conventional Single Carrier Modulation (SCM), and show that it provides substantial performance improvements over SCM. 1. It divides the channel into narrowband, flat fading, subchannels and thus it is more resistant to frequency selective fading as compared to single carrier systems. 2. By using FFT techniques, it is computationally efficient. 3. It can be combined with coding and interleaving to recover symbols lost due to the frequency selectivity of