Frequency-modulation continuous-wave radar self-interference elimination method based on fractional order least mean square

Abstract

The invention discloses a frequency-modulation continuous-wave radar self-interference elimination method based on a fractional order least mean square. In the method, a frequency-modulation continuous-wave radar system uses a baseband de-sloping working mode, and operation of radio frequency domain self-interference cancellation is taken as a precondition. The method comprises the following stepsof firstly, carrying out multipath phase modulation on a baseband emission signal of a frequency-modulation continuous-wave radar to generate a reference signal; secondly, carrying out multipath amplitude modulation on the reference signal and generating a cancellation signal through multipath vector synthesis; then, before baseband de-sloping processing, carrying out self-interference cancellation on the cancellation signal and a radar receiving signal; and finally, using a fractional order least mean square algorithm to carry out feedback adjusting on multipath modulation coefficients so that the cancellation signal approaches the self-interference signal and a purpose of self-interference signal elimination is realized. In the invention, the self-interference signal in the radar receiving signal can be restrained and a target signal is not influenced so as to increase a detection probability and precision of the radar to a target.

Description

technical field [0001] The invention belongs to the technical field of radar signal processing, and in particular relates to a method for self-interference elimination of frequency modulation continuous wave radar based on fractional least mean square, which is applied to frequency modulation continuous wave radar systems. Background technique [0002] Frequency modulated continuous wave radar is widely used in military and civilian fields, such as target detection, tracking and identification, navigation, speed measurement and ranging, etc. Compared with traditional pulse radar, FM continuous wave radar has the advantages of low power and low cost, but the transceiver isolation of FM continuous wave radar is low, so that the transmitted signal will partly leak or enter FM continuous wave through close-range reflection The radar receiving chain forms a self-jamming signal. The power of the self-jamming signal is often much greater than the target echo signal. When the power ...

AI Technical Summary

Problems solved by technology

The problem with this method is that the digital auxiliary system is used in the cancellation system, and the signal processing includes the digital domain and the radio frequency domain, which requires many devices, complex structure and high cost; the signal is first transmitted from the radio frequency domain to the digital domain for processing. Processing, and then fed back to the RF domain, resulting in a long signal processing chain, making the response of the self-interference cancellation system slow and introducing more nonlinear noise

In addition, the convergence speed of the traditional gradient algorithm is relatively low. When dealing with non-stationary signals, the tracking ability of the algorithm is weak, and the effect of self-interference elimination is not good.

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