Joint Detection and Decoding in LDPC-Based Space-Time Coded MIMO-OFDM Systems via Linear Programming

Abstract

This work proposes a novel linear programming approach for the joint detection and decoding of LDPC-based space-time (ST) coded signals in multi-antenna orthogonal frequency division multiplexing (OFDM) systems. While traditional receivers typically decouple the detection and decoding processes as two disjunctive blocks or require iterative turbo exchange of extrinsic information between the soft detector and decoder, we formulate a joint linear program (LP) by exploiting the constraints imposed on the data symbols, training symbols, noise subspace as well as channel code. In consideration of the vast amount of LDPC parity check inequalities, we further present an adaptive procedure to significantly reduce the complexity of the joint LP receiver. Our LP-based receivers outperform existing receivers with substantial performance gains. Moreover, the proposed joint LP receiver demonstrates strong robustness when pilot symbols are sparsely arranged on subcarriers.

An Expurgated Union Bound of Punctured Space-Time Turbo Codes

“…An interesting direction for future work include the determination of the dominant set for STTuCs with QAM modulation [8], [14] for more general fading channels as well as the application of the technique proposed in this work to develop bounds on the bit error probability (BER). The derivation of FER/BER bounds for LDPC-based spacetime codes [27] can also be studied in the future. Fig.…”

Low‐complexity multiple‐signal joint decoding for overlapped x domain multiplexing signalling

“…With comparison to bit‐flipping algorithm [20], MSJD algorithm requires no flips and iterations, and thus avoid high computational complexity and convergence difficulty under low SNR region. In addition, the proposed algorithm can be coupled with decision feedback equaliser [24] and joint detection such as linear programming [25–27] to combat error propagation which would be caused by removing wrong decoded results in (12). The BER performance of the proposed algorithm will be further improved with the aid of the methods mentioned along with increased computational complexity.…”

A New Algorithm for Improved Blind Detection of Polar Coded PDCCH in 5G New Radio

“…Recently, a new type of receiver based on joint detection and decoding has been proposed [22], [23]. Transforming the Galois field code constraints into a set of linear inequality constraints in the Euclidean field, a joint linear programing (LP) receiver can leverage the constraints imposed by modulated data symbols, training symbols, noise subspace, and the LPDC code to achieve improved performance.…”