Design of a Concatenated Coding Scheme for a Bit-Shift Channel

In this work, we propose a concatenated coding scheme with iterative decoding for a bit-shift channel. In more detail, we consider the serial concatenation of an outer error-correcting code with an inner modulation code, possibly preceded by an accumulator to improve iterative decoding performance. The bit-shift channel was originally proposed for magnetic and optical recoding channels, but has recently been popular for inductively coupled channels. In particular, we search for optimal encoder mappings from an iterative decoding perspective for the inner modulation code, which has been designed to be single bit-shift error-correcting and also to have large average power. This is important in inductively coupled channels, since the receiver (or tag) gets its entire power from the received signal, and the information should be modulated in a way that maximizes the power transferred to the tag.