基于Hilbert变换的中频采样技术及其硬件实现

Intermediate Frequency Sampling Based on the Hilbert Transform and Its Hardware Implementation

研究用一种中频采样和数字信号正交变换理论实现脉冲多普勒雷达信号正交采样的新技术.用高速中频采样后,按一定规律抽取数据的数字方法实现了信号频谱的单边化和下变频,考虑到PD雷达多通道采样的一致性和实际需求,利用现有的芯片技术,实现两路信号采集,大大简化了板卡硬件设计的复杂性.板卡性能测试表明,通过简单的数字信号处理可实现对信号的近似Hilbert变换,并获得了良好的镜频抑制性能.

Provides a concrete scheme applying IF sampling and quadrature transform to realize the quadrature sampling of pulsed Doppler radar signal. High speed IF sampling combined with decimation pro rate can lead to unilateral spectrum and down-converter of signal spectrum. Considering the multichannel consistency and practical requirements, a dual channel ADC chip has been adopted to simplify the hardware design. Test results reveal that approximate Hilbert transform of signal by simple digital signal processing can achieve better performance of mirror frequency rejection.