Implementation Of High Performance Error-Correcting Codes For Space Applications

Remote control communication technology is an important part of space communication,which usually uses short data-frame,requires high reliability and works in real time.To ensure the highly reliable transmission,channel coding techniques are used to reduce the error probability of the system.The long codes usually have the superior error correction performance,but they are not suitable for the characteristics of the remote data frame and do not satisfy the requirement that encoder and decoder should be simple.Therefore,the short block code which has high error-correcting capability is usually adopted in remote control transmission.In order to satisfy the requirements of reliable transmission in the remote communication system,we use a kind of non-binary short codes with the special construction.This kind of codes has the advantage of easily designing and flexible constructing.Moreover,the soft-decision decoding algorithm which is based on a fast Fourier transform(FFT)is evaluated for these short codes with different length and code rates.Results show that the algorithm has low decoding complexity and high performance,realizing a good compromise between performance and complexity.Furthermore,in order to verify the performance of the decoding algorithm,a hardware decoder for this kind of non-binary short codes is designed based on FPGA.For the purpose of verifying the correctness of the decoder and testing the performance,we build an emulation system which uses the computer to communicate through Ethernet interface with the FPGA board and transmits fixed point data which is obtained by a series of processing,such as modulation,adding noise and quantification using UDP protocol.In summary,we simulated the performance of non-binary short codes which are defined on high order finite field.Furthermore,we design a decoder for this type of non-binary short codes and build a test system based on the FPGA to verify the performance of the codes.Results show that the non-binary short codes using soft-decision decoding algorithm based on FFT have excellent error correction performance.