On Transmission of Two Correlated Gaussian Memoryless Sources over a Gaussian MAC using Delay-Free Mappings

This paper considers delay-free, low complexity, joint source-channel coding (JSCC) for communication of two correlated Gaussian memoryless sources over a Gaussian Multiple Access Channel (GMAC). Schemes are proposed both for cooperative and distributed encoders. The cooperative case is mainly studied to get an idea about how close one can expect to get to the performance upper bound with a zero delay constraint. The main contribution of the paper are distributed JSCC schemes. Two schemes are proposed: One fully discrete scheme based on nested scalar quantization and a hybrid discrete-analog scheme based on a scalar quantizer and a linear continuous mapping. Both transmitand received power constraints are considered. The proposed schemes are robust against noise and show promising performance which improve with increasing correlation.