Study Of High-speed, Broad Band Technique For Frequency Measurement

In the domain of ECM, the frequency information of radar signal is important parameter for signal choosing, menace recognizing and guidance ECM. The signal environment of ECM is more and more complex, so frequency measurement methods must be high-speed and precise in broad frequency band. Accuracy of measuring radar carrier frequency with traditional analogue receiver is low, and not satisfying. However, with Large Scale Integrated circuit technique development, many excellent digital methods of measuring frequency can be used in digital receiver.In this paper, several important algorithms of frequency measurement are analysed in detail, and these algorithms can simultaneously process much signal. Afterward, some schemes of frequency measurement with sub-Nyquist sampling rate are summed up. In the schemes, framework with one time-delay channel is specially analysed, and its method of frequency measurement is improved. Finally, the method of digital channelized filters combining narrowband precise frequency measurement is discussed. And the scheme based on DFT filters is simulated to prove its performance. The study shows that the scheme of digital channelized filters combining digital algorithms can accurately measure frequency with high rate.