Research On The Key Technology Of Interference Suppression Reception In Aerospace Telemetry Tracing And Command Communication Link

The rapid development of aerospace technology promotes the construction and improvement of aerospace Telemetry Tracing and Command(TT&C)systems.The openness of aerospace TT&C communication link makes it extremely vulnerable to hostile interference attacks,which seriously affects the communication performance.The communication security of aerospace TT&C is related to the national strategic information security,so it is essential to improve the interference protection capabilities of the aerospace TT&C system.Aiming at the anti-jamming requirements of aerospace TT&C link receivers,this paper studies the transform domain interference suppression technology for single receiving antenna and array receiving antenna,and optimizes the anti-jamming performance of the system by using the difference in the transform domain characteristics of interference signal.The main work of the thesis is as follows:First,the current situation of interference protection and typical key anti-jamming technologies of aerospace TT&C system are analyzed.This paper analyzes the domestic and foreign aerospace TT&C system communication system and interference protection capabilities,and compares the classical receiver anti-jamming technology from the perspective of multi-dimensional domains,which provides a theoretical reference for the subsequent interference suppression in transform domain.Second,a single receiving antenna transform domain interference suppression scheme is designed.Using the difference in the statistical characteristics of the transform domain between the spread spectrum signal and the interference signal,the two have different power distribution characteristics in the eigen domain.The received signal is transformed into the eigen domain for interference suppression,and then converted back to the time domain for subsequent demodulation operations.In order to improve engineering practicability,an adaptive iterative algorithm based on RLS is designed to achieve low complexity fast real-time interference suppression.The simulation results show that when the spreading gain is 1023,the eigen domain interference suppression algorithm can achieve 50 d B interference suppression capability,and the signal to noise ratio loss after interference suppression is less than 2d B.Third,a joint interference suppression method in the space and eigen domain of the array receiving antenna is proposed.The proposed algorithm takes advantage of the difference in power distribution between interference and communication signals.The power of narrowband interference in the eigen domain presents a concentrated distribution,while the power of communication signal is uniformly distributed.The multi-antenna time domain received signal is transformed into the eigen domain for multi-antenna interference suppression to achieve the goal of jointly suppressing interference in the space and eigen domain.Analysis and simulation results show that the proposed algorithm not only can effectively suppress different incoming interference,especially for the same direction narrowband interference,the traditional space time interference suppression algorithm is invalid,and the proposed algorithm is still effective.This paper studies the interference suppression method in the transform domain of aerospace TT&C system,which improves the interference suppression performance of the system and provides theoretical support for the design of aerospace TT&C system anti-jamming receiver.