Distortion Exponents of Two-Way Relaying Networks with Multiple-Access Broadcast Protocol

In this paper, we study the end-to-end distortions when transmitting two Gaussian signals in a three-node, half-duplex, and two-way relaying network, where two users communicate in both directions with the help of one relay, and can transmit at different rates. We focus on the two-phase Multiple-Access Broadcast (MABC) cooperation protocol with decode-and-forward (DF), amplify-and-forward (AF), or compress-and-forward (CF) strategy at the relay. In each case, we analyze the achievable distortion exponents of the two sources at high signal-to-noise ratio (SNR) regime. The results illustrate the effects of the bandwidth ratio and cooperation strategies on the optimized distortion exponents. We also derive the achievable diversity-multiplexing gain tradeoffs of these two-way relaying protocols.