Multi-terminal source coding through a relay

This paper studies a multi -terminal source coding problem, where two terminals possess two (correlated) Gaussian sources to be compressed and delivered to the destination through an intermediate relay. Unlike the CEO and conventional two terminal source coding problems as well as point-to-point relay source coding problem, lattices are found to play an important role in achieving "good" rates for this problem setting. Two achievable strategies compute-and-forward and compress-and forward are used to develop achievable rates for this problem setting. For the symmetric case, the inner and outer bounds developed are shown to be within 1/2 bits of each other.