Multi-station inter-frequency response receiving system

Abstract

The invention presents a multi-station different-frequency signal response receiving system, and aims to provide a multi-station different-frequency receiving response system characterized by short single-point residence time, adaptability to multiple dot frequencies and high reliability in order to overcome inter-modulation interference between multiple dot frequencies. The technical scheme is as follows: after the system receives radio frequency signals of different frequencies, a digital signal processing unit sends a default frequency point to a local oscillation signal generator, the received radio frequency signals and local oscillation signals generated by the local oscillation signal generator are mixed in a mixer, a fixed intermediate frequency output after mixing is sent to the digital signal processing unit, the digital signal processing unit samples fixed intermediate-frequency signals and sends sampling data to a carrier ring in an FPGA, the carrier ring carries out frequency search based on predetermined multi-frequency sweeping and completes carrier locking and tracking, a decision is made using an automatic residing multi-dot-frequency polling algorithm, a carrier ring locking decision instruction is given, the local oscillation frequency is changed according to the decision instruction of the algorithm, and then, carrier-locked automatic-residing multi-station different-frequency signal receiving is completed.

Description

technical field [0001] The invention relates to a multi-station inter-frequency response receiving system. Background technique [0002] In order to cooperate with the flight test of the aircraft, the transponder receiving system is installed in the aircraft. When the aircraft fails, in order to ensure the safety of personnel and property, and avoid unnecessary international disputes and technical leaks, the transponder receiving system will cooperate with the ground station to work in a timely manner. Answer and take measures to blow up the aircraft. In order to improve the system's anti-interference ability and flexibility of use, multiple sets of ground stations work with different frequency carriers, which requires the transponder receiving system to be able to cooperate with each ground station and have multi-frequency operating characteristics. [0003] At present, the most widely used solution in the transponder receiving system is the multi-crystal oscillator simula...

AI Technical Summary

Problems solved by technology

[0003] At present, the most used scheme of the transponder receiving system is the multi-crystal oscillator simulation scheme. Using this scheme is easy to cause intermodulation interference between multi-point frequencies, and the single-point dwell time is long.

In addition, this design scheme will lead to problems such as increased equipment volume, high complexity, and reduced reliability, and it is difficult to meet high-performance requirements such as small size, light weight, low power consumption, high reliability, and complex electromagnetic environments.

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