Throughput optimization for non-uniform linear antenna arrays in multicell WiMAX systems

AWiMAX multi-cell system conforming the IEEE 802.16-2004 standard which supports multiple antennas and OFDM modulation is considered. Focusing on the uplink, we show that Signal to Interference plus Noise Ratio (SINR) degradation caused by fading impairments can be considerably reduced by exploiting adaptive modulation/ coding techniques in conjunction with a non-uniform antenna array with optimized spacings. Specically, a trade off between diversity gain and array interference reduction capability is considered so as to derive closed form solutions for the antenna spacings. Performance improvements are investigated by analyzing the cell coverage and the average throughput for various cellular plannings, antenna congurations and channel models. For completeness, SINR degradation due to shadowing effect is also considered.