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Abstract
This thesis proposes the use of block turbo codes for transmitting non-uniform binary memoryless sources over AWGN channels. As opposed to standard convolutional turbo codes, block turbo codes are known to achieve good performance for high code rates, up to 98% of the channel capacity for uniform sources. The objective of this thesis is to investigate if such a performance is also achievable for non-uniform sources. The idea is to use a joint source-channel (or source controlled) coding scheme to exploit the statistics of the binary source at the decoder.
Block turbo codes are a class of product codes, which can be decoded by iteratively decoding the component codes. Each component code is decoded using the Chase algorithm, which is a low-complexity suboptimum algorithm [8] for near Maximum-Likelihood decoding of linear block codes. In this thesis, we propose decoding modifications to take into account the non-uniform nature of the source in the decoding of block turbo codes.
