基于RF DAC的宽带高斯噪声源的设计与实现

Design and implementation of wideband gaussian noise source based on RF DAC

设计了一种基于现场可编程门阵列(Field Programmable Gate Array,FPGA)和射频级数模转换器(Radio Frequency Digital to Analog Converter,RF DAC)的宽带高斯噪声源。该噪声源将优先编码器原理运用到非均匀分段拟合映射曲线中,通过并行伪码产生结构生成均匀分布的伪码序列,接着利用非均匀折线拟合的方法将伪码序列映射为高斯分布的高速数字高斯噪声,然后通过RF DAC输出宽带高斯噪声。在Xilinx Virtex7 XC7VX485T和ADI AD9129搭建的验证平台上的测试结果表明,该噪声源能输出±4σ(σ为标准差)的高斯噪声,噪声带宽可达1.2 GHz,并且只消耗FPGA约0.3%的资源。

The design of a wideband Gaussian noise source is presented,which is based on FPGA （Field Programmable Gate Array） and RF DAC（Radio Frequency Digital to Analog Converter）. The principle of priority encoder is applied to non-uniform piecewise curve fitting, and uniformly distributed pseudo-code sequence is mapped to Gaussian noise sequence by the method of non-uniformly piecewise curve fitting, which is generated by parallel generating structure. Finally broadband Gaussian noise output through RF DAC. The test results on Xilinx Virtex7 XC7VX485T and ADI AD9129 show that bandwidth of noise can reach 1.2 GHz, and about O. 3% of the resources is consumed.