Joint Optimization of Digital Communication Systems

This paper discusses integrated system design with emphasis on wireless audio and video communication applications. In the wireless communication scenario both source and channel coding and modulation are essential components of the system, and delay and complexity is often severely constrained. Joint optimization is a promising alternative under such conditions, and several techniques have been introduced during the recent years; The source and channel coders can be integrated, e.g. by optimizing the quantizers taking the channel conditions into account. In so-called coded modulation systems, the operations of channel coding and modulation are integrated for better overall eeciency. Finally, the source coder and the modulator can be integrated by coupling the source signal and the modulator signal space in such a way that the impact of channel errors is perceptually minimized.