A hardware Gaussian noise generator using the Wallace method

Abstract

We describe a hardware Gaussian noise generator based on the Wallace method used for a hardware simulation system. Our noise generator accurately models a true Gaussian probability density function even at high /spl sigma/ values. We evaluate its properties using: 1) several different statistical tests, including the chi-square test and the Anderson-Darling test and 2) an application for decoding of low-density parity-check (LDPC) codes. Our design is implemented on a Xilinx Virtex-II XC2V4000-6 field-programmable gate array (FPGA) at 155 MHz; it takes up 3% of the device and produces 155 million samples per second, which is three times faster than a 2.6-GHz Pentium-IV PC. Another implementation on a Xilinx Spartan-III XC3S200E-5 FPGA at 106 MHz is two times faster than the software version. Further improvement in performance can be obtained by concurrent execution: 20 parallel instances of the noise generator on an XC2V4000-6 FPGA at 115 MHz can run 51 times faster than software on a 2.6-GHz Pentium-IV PC.