Multiple description source coding for cognitive radio systems

Multiple description coding (MDC) is applied for delay-sensitive data traffic to alleviate interruptions caused by primary users in cognitive radio systems. For Gaussian source, a simplified algorithm for the exhaustive search of optimal distortions and rates is proposed based on the achievable region of coding rates and delay requirement. For practical realtime image coding, source splitting is applied to generate multiple descriptions. When there is a single channel, two successive descriptions are composed of large and small coefficients in discrete cosine transform (DCT) domain, respectively. When there are two channels, even and odd coefficients in DCT domain are used to construct two parallel descriptions. Numerical results show that MDC can effectively combat the interruptions caused by primary users in cognitive radio systems.