An LDPC error control strategy for low earth orbit satellite communication link applications

[摘要] ENGLISH ABSTRACT: Low earth orbit (LEO) satellite communication presents a unique environmentwhich inherently di ers from most other communication channels.Due to the varying orbital patterns of LEO satellites the link exhibits varyinglink margins. Limited communication time windows need to be optimised tomaximise the volumetric data throughput.Large coding gains can be obtained by the implementation of forward errorcorrection codes. This thesis presents a means for optimising the datathroughput of LEO satellite communication through the implementation of amission speci c error control strategy. Low density parity check (LDPC) codesare versatile and present good error performances at many di erent code ratesand block lengths. With power limitations on the space segment and remoteground stations, hardware utilisation e ciency must be optimised to reducepower consumption. In response to this requirement, this thesis evaluatesvarious algorithms for LDPC decoders.An iterative LDPC decoder, implementing an approximation algorithm,is presented as a low complexity solution with good error performance. Theproposed solution provides a very good balance between required hardwarecomplexity and coding performance. It was found that many parameters ofthe decoders and codes can be altered to allow the implementation of thesecodes in systems with varying memory and processing capabilities.

[发布机构] Stellenbosch University