FPGA implementation of elementary generalized unitary rotation with CORDIC based architecture

Abstract

This paper describes the first trial of implementation of generalized unitary Jacobi-like rotation (the device is called EGU-rotator, further referred to as rotator) purely based on the CORDIC algorithm into Altera's and Xilinx FPGAs. The basics and examples for factorization of the generalized rotation matrix (further, matrix) are given. The number of matrix shapes alternates in the range from 4 to 64 depending on the range of used angles (parameters). A unified algorithm for implementation of parametrical rotator is provided. Reconfigurable architecture of rotator is briefly described. The choice of architecture is determined by 3 addresses and they correspond to different shapes of the matrix. The comparison of device resources for different wordlengths, the number of CORDIC iterations and platforms is given. The complex rotator works approximately 3 times slower and consumes approximately 5 times more device resources than a single CORDIC rotator.