Low complexity MIMO for WiMedia UWB

This article explores and quantifies the correlation of adjacent subcarriers in WiMedia UWB MB OFDM symbols. It is shown that in 70% of cases the energy of adjacent subcarriers differs by less than 3 dB. This finding is considered in the design of a novel antenna selection algorithm. The classical algorithm performs antenna selection for individual subcarriers, which is associated with high complexity. This paper proposes a method with reduced complexity by performing joint selection for groups of subcarriers. This proposal is evaluated for a 1 × 1 system, a 2 × 1 system with optimum antenna selection, and with a 2 × 1 with antenna selection for bundles of 2, 4, and 8 subcarriers for broadside and end-fire arrays. It is shown that optimum antenna selection can significantly enhance the range of WiMedia OFDM systems. Furthermore, antenna selection for groups of two subcarriers is shown to provide almost optimum performance whilst the complexity of the algorithm is reduced by 50%.