Performance of Hybrid Concatenated Trellis Codes CPFSK with Iterative Decoding over Fading Channels

TL;DR

This paper evaluates the performance of hybrid concatenated trellis codes combined with CPFSK over fading channels, proposing a low complexity iterative decoding method and deriving analytical bounds for different coding schemes.

Contribution

It introduces a hybrid concatenated trellis coding scheme with iterative decoding for CPFSK over fading channels, including analytical bounds and design guidelines.

Findings

Hybrid coding schemes outperform traditional methods.

Iterative decoding improves error performance.

Analytical bounds guide optimal code design.

Abstract

Concatenation is a method of building long codes out of shorter ones, it attempts to meet the problem of decoding complexity by breaking the required computation into manageable segments. Concatenated Continuous Phase Frequency Shift Keying (CPFSK) facilitates powerful error correction. CPFSK also has the advantage of being bandwidth efficient and compatible with nonlinear amplifiers. Bandwidth efficient concatenated coded modulation schemes were designed for communication over Additive White Gaussian noise (AWGN), and Rayleigh fading channels. An analytical bounds on the performance of serial concatenated convolutional codes (SCCC), and parallel concatenated convolutionalcodes (PCCC), were derived as a base of comparison with the third category known as hybrid concatenated trellis codes scheme (HCTC). An upper bound to the average maximum-likelihood bit error probability of the three schemes were obtained. Design rules for the parallel, outer, and inner codes that maximize the interleaver's gain were discussed. Finally, a low complexity iterative decoding algorithm that yields a better performance is proposed.