Near-Capacity Irregular Variable Length Coding and Irregular Unity Rate Coding

In this contribution we introduce an EXtrinsic Information Transfer (EXIT) chart matching technique for the design of two serially concatenated irregular codecs, each constituted by a variety of component codes. This approach facilitates a higher degree of design freedom than matching the EXIT function of an irregular codec to that of a regular codec, comprising only a single component code. As a result, a narrower EXIT chart tunnel can be created, facilitating operation at E-b/N-o values that are closer to the channel's capacity bound. This is demonstrated for a serial concatenation of iteratively decoded Irregular Variable Length Coding (IrVLC) and Irregular Unity Rate Coding (IrURC), which is favourably compared with an IrVLC and regular Unity Rate Coding (URC) based benchmarker. Finally, we show that the iterative decoding complexity of our IrVLC-IrURC scheme can be reduced by about 25% upon employing a method of jointly performing EXIT chart matching, while seeking a reduced iterative decoding complexity.