Energy efficient hybrid transmission of correlated sources over the MAC

In this work, we investigate how hybrid analog- digital coding improves transmission energy efficiency over pure analog or digital schemes. In particular, transmission of correlated sources over the multiple access channels (MAC) is studied. Compared to other works on joint source-channel coding, we consider the general scenario where the source and channel bandwidths are not naturally matched. We first consider lossy transmission of Gaussian sources over the Gaussian noisy MAC. We then treat a Slepian-Wolf problem with binary sources and noisy channels. In both cases we show that hybrid transmission is energy efficient and its energy savings over pure analog or digital transmission is on the order of 3-5 dB.