Receiver Design for Alamouti Coded FBMC System in Highly Frequency Selective Channels

Alamouti coded filter bank multicarrier systems suffer from severe performance degradation in highly frequency selective channels. To address the above problem, we propose a novel Alamouti decoding receiver based on frequency spreading/despreading, where the Alamouti decoding module is moved to the front of the frequency despreading module. Unlike the traditional subcarrier-based Alamouti decoding scheme, the Alamouti decoding in the proposed receiver could be performed on each frequency point to better combat the frequency selectivity. Moreover, the full diversity is achieved on each frequency point by introducing a phase factor before Alamouti decoding. Simulation results demonstrate the performance advantages of our proposed receiver over the traditional scheme in highly frequency selective channels.