Unequal error protection schemes for image transmission over fading channels

Abstract

In this paper, an unequal error protection (UEP) scheme is investigated for highly error sensitive joint photographic experts group (JPEG) images transmitted over uncorrelated flat Rayleigh fading channels. The powerful source compression involved with JPEG often leads to increased error susceptibility. In particular, corruption of the file headers may result in a transmitted file unreadable to the target application. To alleviate this problem, additional error protection may be provided for critical data segments, such as headers and control markers, whilst less error protection may be allocated to payload data. This may be accomplished by the proposed UEP scheme, which uses a powerful extended Golay code for the critical bits, and an extended Hamming code, having reduced decoding complexity and storage space requirements, for the less important payload bits. Simulation results obtained using symbol-by-symbol maximum a posteriori probability (MAP) decoding demonstrate that the proposed UEP scheme displays significant performance improvement compared to the traditional equal error protection (EEP) scheme, in terms of the percentage of readable files.