GNSS接收机抗干扰电路的硬件实现  

Hardware implementation of anti-jamming circuit of GNSS receiver

作　　者：王依婷 陈杰[1] 杨颖[1] 刘学勇[1] 李健[1] 巴晓辉[1,2] Wang Yiting;Chen Jie;Yang Ying;Liu Xueyong;Li Jian;Ba Xiaohui(Institute of Microelectronics of Chinese Academy of Sciences,Beijing 100029,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院微电子研究所,北京100029 [2]中国科学院大学,北京100049

出　　处：《东南大学学报（自然科学版）》2021年第2期350-356,共7页Journal of Southeast University：Natural Science Edition

基　　金：国家重点研发计划资助项目(2019YFB2204200).

摘　　要：针对全相位FFT/FFT(apFFT/FFT)综合相差法硬件资源和功耗大的问题,基于FFT算法求解最大峰值谱线位置仅与各谱线峰值相对大小有关的特点,提出一种用于减少FFT电路面积的阈值判断移位方法.首先对apFFT/FFT综合相差法与修正Rife算法进行性能比较;然后利用阈值判断移位方法对apFFT/FFT综合相差法硬件实现中的FFT运算结构进行改进,称为改进apFFT/FFT算法,使FFT计算位宽减少1/2;最后将改进的apFFT/FFT综合相差法硬件结构应用到GNSS抗干扰模块的电路实现中,并利用FPGA进行抗干扰功能验证.结果表明,在基本不降低频率估计精度下,改进apFFT/FFT算法可以减少约50%的面积资源和功耗;在接近相同面积资源和功耗下,改进apFFT/FFT算法的频率估计精度约为修正Rife算法的2倍;GNSS抗干扰硬件模块具备良好的滤除干扰能力.Aiming at the problem of large hardware resources and power consumption of the all-phase FFT/FFT(apFFT/FFT)comprehensive phase difference method,based on the fact that the position of the maximum peak spectral line of FFT algorithm is only related to the relative size of each spectral line peak,a threshold judgment shift method is proposed to reduce the area of the FFT circuit.First,the performances of the apFFT/FFT comprehensive phase difference method and the modified Rife(MRife)algorithm are compared.Then,the calculation structure of FFT in hardware implementation of the apFFT/FFT comprehensive phase difference method is improved by using the threshold judgment shift method,called the improved apFFT/FFT algorithm,and the calculation bit width of FFT is reduced by 1/2.Finally,the improved hardware structure of the apFFT/FFT comprehensive phase difference method is applied to the circuit implementation of the GNSS anti-jamming module,and the anti-jamming function is verified by FPGA.The results show that the improved apFFT/FFT algorithm can reduce the area resources and the power consumption by about 50%without decreasing the frequency estimation accuracy.And the frequency estimation accuracy of the improved apFFT/FFT algorithm is approximately twice that of the MRife algorithm at almost the same area resources and the power consumption.The GNSS anti-jamming hardware module has a good ability for filtering interference.

关 键 词：接收机 抗干扰模块 修正Rife 全相位FFT/FFT(apFFT/FFT)综合相差法 

分 类 号：TN967.1[电子电信—信号与信息处理]