Forward-substitution-based generalized eigenvalue decomposition processor for MU-MIMO precoding

To improve the spectrum efficiency in wireless communication systems, multiple-input multiple-output (MIMO) technology uses multiple antennas and allows several users to share the same spectrum and antennas by using precoding technique. In the leakage-based precoding technique, generalized eigenvalue decomposition (GEVD) must generate many precoding matrices for all users in the base station to avoid co-channel interference. This paper presents a GEVD algorithm based on forward substitution (FS) scheme to avoid matrix inversion operations. This research also designed and implemented the GEVD processor by using a 40nm CMOS technology. The synthesis results show that the FS-based GEVD processor can reduce area cost by 52% and improve the processing throughput by 12% compared to our previous GEVD [1] processor based on triangular matrix inversion with block multiplication.