Research On Interference Mitigation Methods Based On Weak Signal Detection

Technical advances in electromagnetics, signal processing and processing power have led to a significant increase in sensitivity and accuracy in radio telescopes. With this increase in sensitivity, radio frequency interference(RFI) has become a much larger problem. The notable growth in the application field of radio business as well as self-generated RFI has further escalated this problem. In order to utilize the full capabilities of modern radio telescopes, RFI mitigation is required on the captured signals. With the enormous data rates of modern radio telescopes, managing RFI has become increasingly difficult, and in order to utilize the full captured radio data, more accurate RFI mitigation strategies will be more and more necessary.In response to the above scientific background, and fully integrate the scientific objectives of the observation of weak signals, this paper focuses on three aspects of research work: the evaluation criteria of interference mitigation methods for the back-end application of weak signal processing, interference mitigation methods and the test design of interference mitigation. Firstly, this paper introduces several programs of interference mitigation process, aiming at the typical back-end application of radio astronomy observation. Secondly, this paper studies a method of interference mitigation based on source model reconstruction and improves the estimation accuracy of the interference signal and the interference cancellation effect in the known form of a source of interference. For the unknown prior information sources of interference, this paper studies the adaptive filtering method and improves the interference mitigation performance of the adaptive filtering method by improving the step-size which is the most important algorithm parameter. Finally, this paper designs a set of weak signal interference to radio astronomy pilot program to meet the requirements of the radio data acquisition, analyzing the performance test of a data acquisition system of multi-channel and high-speed recording.