Beamforming for interference mitigation and its implementation on an SDR baseband processor

We present the first implementation of a distributed beam-forming algorithm for interference mitigation on an SDR baseband processor. Co-channel interference (CCI) is becoming a major source of impairments in wireless communications and distributed beamforming is a promising technique to mitigate its negative impact. However, such schemes are challenging to implement in practical scenarios due to their complexity and synchronization requirements. In this paper, we report on implementation of a suboptimal, yet efficient, beamforming scheme for CCI mitigation and present the complexity modeling and algorithm transformations for achieving numerically stability. We also present the fixed-point quantization and the proper mapping on a parallel programmable baseband architecture aimed for software-defined radio (SDR). We optimize this algorithm for a coarse grained reconfigurable array (CGRA) processor and evaluate it in the context of the LTE standard.