实时高精度雷达噪声信号产生方法与FPGA实现

针对各种典型分布的噪声信号在雷达系统半实物仿真和噪声雷达波形设计中的实际需求，基于Box-Muller算法提出了一种能够实时产生多种分布特性噪声的信号生成方法。首先使用线性反馈移位寄存器产生均匀分布随机序列，然后利用能够实现高精度、低延迟的坐标旋转数字算法(Coordinate Rotation Digital Computer,CORDIC)实现Box-Muller变换中复杂函数的快速计算，将均匀随机序列转换成高斯分布随机序列，最后利用高斯随机序列经过相关数学运算得到其他复杂分布的随机序列，在此基础上产生具有各种分布特性的噪声信号。基于Xilinx XC7VX415T 现场可编程门阵列(Field Programmable Gate Array,FPGA)芯片的实验结果表明，所提方法在保证小数位数据精度为20 b时，可实时产生速率为2.5 Gb/s的高精度随机数据序列，进而生成服从多种函数分布下的噪声信号。所提方法整体资源占用率较少，具有较强的实用性。

A real-time high-precision radar noise signal generation method and FPGA implementation

According to the actual needs of noise signals with various typical probability distribution in radar system hardware-in-the-loop simulation and noise radar waveform design,this paper proposes a signal generation method which can generate multiple distributed noise in real time based on the Box-Muller algorithm.First,linear feedback shift registers are used to generate uniformly distributed random sequences.Then,coordinate rotation digital computer (CORDIC) algorithm which can achieve high precision and low delay is used to achieve rapid calculation of complex functions in the Box-Muller transformation.After that,uniform distributed random sequences are converted into Gaussian distribution random sequences.Finally,the Gaussian random sequences are used to obtain other complex distributed random sequences through related mathematical operations.On this basis,noise signals with various distribution characteristics are generated.The experimental results based on the Xilinx XC7VX415T field programmable gate array (FPGA) chip show that the proposed method can generate high-precision random data sequences with a rate of 2.5 Gb/s in real time while ensuring the accuracy of decimal data to 20 b,and then generate noise signals that obey various function distributions.The overall resource occupancy rate of the proposed method is small,and it has strong practicability.