Joint detection and decoding of LDPC coded distributed space-time signaling in wireless relay networks via linear programming

We develop a linear programming based approach for the joint detection and decoding of LDPC coded distributed space-time signaling transmitted in a wireless relay network. Traditional receivers typically decouple the detection and decoding processes as two separate blocks or require iterative turbo exchange of extrinsic information between the soft detector and decoder. We exploit the constraints imposed on the channel input signals and jointly consider the training symbols as well as the LDPC code information by formulating a unified linear programming (LP) receiver. Moreover, in consideration of the vast amount of LDPC parity check inequalities, we present an adaptive procedure to significantly reduce the complexity of the proposed LP receiver.