CORDIC-Based Enhanced Systolic Array Architecture for QR Decomposition

Abstract

Multiple input multiple output (MIMO) with orthogonal frequency division multiplexing (OFDM) systems typically use orthogonal-triangular (QR) decomposition. In this article, we present an enhanced systolic array architecture to realize QR decomposition based on the Givens rotation (GR) method for a 4 × 4 real matrix. The coordinate rotation digital computer (CORDIC) algorithm is adopted and modified to speed up and simplify the process of GR. To verify the function and evaluate the performance, the proposed architectures are validated on a Virtex 5 FPGA development platform. Compared to a commercial implementation of vectoring CORDIC, the enhanced vectoring CORDIC is presented that uses 37.7% less hardware resources, dissipates 71.6% less power, and provides a 1.8 times speedup while maintaining the same computation accuracy. The enhanced QR systolic array architecture based on the enhanced vectoring CORDIC saves 24.5% in power dissipation, provides a factor of 1.5-fold improvement in throughput, and the hardware efficiency is improved 1.45-fold with no accuracy penalty when compared to our previously proposed QR systolic array architecture.