Performance Analysis of Systematic Upper Layer FEC Codes and Interleaving in Land Mobile Satellite Channels

摘要

This paper provides an analytical method for evaluating the performance of upper layer forward error correction (FEC), when used together with interleaving on land mobile satellite channels, in terms of residual (after decoding) packet loss rate (PLR). In addition, the analysis highlights the overheads introduced by this technique, which depend on the channel statistics, in terms of additional packet delivery delay, bandwidth consumption, and computation power required. We show why the interleaver is mandatory in some environments, due to the severe disruptive characteristics of the channel, according to measurement campaigns promoted by the European Space Agency. This analysis provides the expression of the residual PLR when systematic FEC coding blocks are interleaved at the packet level (i.e., when a cyclic redundancy check and a sequence number identify a correct data unit). This method can be employed for the performance evaluation of recent and future mobile communication systems that take advantage of upper layer FEC and interleaving techniques.