Mixed analog/digital receiver beamforming for 60GHz OFDM System with co-channel interference mitigation

Large antenna arrays are usually used in 60GHz for beamforming to compensate the high path loss in this band. IEEE 802.15.3c adopted a beamforming codebook design to reduce the cost and power consumption of the large array, but which is not enough to deal with interference in a dense network. This paper proposed a mixed analog and digital receiver beamforming structure with subarray partition, which keeps the simplicity of the IEEE 802.15.3c codebook antenna design. This structure includes 2 stages: the Analog BeamForming (ABF) stage and the Digital BeamForming (DBF) stage. In the ABF stage, the codeword of each subarray is decided as described in IEEE 802.15.3c standard, and then the combined signal of each subarray is further optimized in the DBF stage based on Minimum Mean Square Error (MMSE) criterion. Simulation results have shown that the system performance against CCI could be significantly increased with only 1 additional Analog-Front-End (AFE) utilizing the proposed structure.