Source fidelity over fading channels: performance of erasure and scalable codes

We consider the transmission of a Gaussian source through a block fading channel. Assuming each block is decoded independently, the received distortion depends on the tradeoff between quantization accuracy and probability of outage. Namely, higher quantization accuracy requires a higher channel code rate, which increases the probability of outage. We first treat an outage as an erasure, and evaluate the received mean distortion with erasure coding across blocks as a function of the code length. We then evaluate the performance of scalable, or multi-resolution coding in which coded layers are superimposed within a coherence block, and the layers are sequentially decoded. Both the rate and power allocated to each layer are optimized. In addition to analyzing the performance with a finite number of layers, we evaluate the mean distortion at high Signal-toNoise Ratios as the number of layers becomes infinite. As the block length of the erasure code increases to infinity, the received disto...

• Type: Journal
• Year: 2008
• Where: TCOM
• Authors: Konstantinos E. Zachariadis, Michael L. Honig, Aggelos K. Katsaggelos
• Keywords: Distortion, Erasure, Quantization Accuracy, TCOM 2008