Fixed-Rate Raptor Code Performance Over Correlated Rayleigh Fading Channels

This work considers fixed-rate Raptor coded transmission over fading channels with memory following the Jakes´ model. The effect of the normalized fade rate on the performance of low-to-moderate rate Raptor codes, when decoded with an improved soft-decision decoding algorithm, is investigated. Results show that, over slow fading channels, the performance of Raptor codes degrades from that of memoryless (fast) fading by 1.5-4.3 dB. Despite this degradation, Raptor codes are shown to provide substantial performance gains of 3-4 dB over serial and parallel concatenated turbo codes, demonstrating their effectiveness as high-performance codes over correlated fading channels.