Research And Implementation Of TPC Codec In Wireless Telemetry System

Telemetry systems play a very important role in the development of our weapon defense.Telemetry equipment mainly includes missile-borne telemetry units and receiving equipment.The development direction of the missile-borne telemetry unit is small size and low power consumption.With the increase of telemetry distance,and in order to ensure the confidentiality and anti-interference of information,channel coding technology is usually introduced.Turbo product code is one of the economical and efficient coding methods.This article first introduces the development history and research overview of telemetry systems and TPC channel coding,and elaborates the basic theory of TPC channel coding and decoding,including the basic structure of coding and commonly used decoding algorithms.Next,the coding structure and traditional soft-decision decoding algorithm are improved in terms of complexity and computation,including euclidean distance calculation,syndrome calculation,solution of optimal codeword and determination of unreliable bits Some parameters that affect the performance of TPC decoding are analyzed.Different parameters are simulated in the Matlab environment and parameter values are specified to the hardware implementation.Then,the design scheme of FPGA implementation of coding and decoding system is given.The extended Hamming code(64,57,4)×(64,57,4) is selected as the subcode for the parallel encoding.The decoding algorithm is based on the improved soft input and soft output of the Chase? algorithm.The functional simulation of the core module is compared with the theoretical results.The latency of TPC parallel coding structure and the complexity and occupied resources of the improved decoding algorithm are reduced.Finally,the hardware debugging results of the coding and decoding system are given.The test results show that,while maintaining good decoding performance,compared with the molded dedicated decoding chip,the use of programmable logic packaged devices has a higher volume performance ratio and flexibility.