FPGA design and implementation of Direct Matrix Inversion based on steepest descent method

This paper presents a reduced-complexity, fixed- point algorithm and efficient VLSI architecture implemented on FPGAs for direct matrix inversion (DMI) beamforming technique for code division multiple access (CDMA) systems equipped with antenna arrays. In this paper, we re-design the direct matrix inversion, wherein a steepest descent method is used to solve the matrix inversion problem in an iterative manner while ensuring good tracking properties in time-varying channels. Fixed point simulations are presented to evaluate the precision requirements of the algorithm. The performance goal is to maximize the number of users, to be served by the base station BTS, on a FPGA device. The targeted FPGA devices are Virtex-II and Virtex-II Pro families of Xilinx.