A complete pipelined MMSE detection architecture in a 4x4 MIMO-OFDM receiver

This paper presents a VLSI architecture of MMSE detection in a 4x4 MIMO-OFDM receiver. Packet-based MIMO-OFDM imposes a considerable throughput requirement on the matrix inversion because of strict timing in frame structure and subcarrier-by-subcarrier basis processing. Pipeline processing oriented algorithms are preferable to tackle this issue. We adopt Strassen's algorithms of matrix inversion and multiplication to circuit design in the MMSE detection. The complete pipelined architecture achieves real-time operation which does not depend on numbers of subcarriers. The designed circuit has been implemented to a 90-nm CMOS process and shows a potential for providing a 2.6-Gbps transmission speed in a 160-MHz signal bandwidth.