Selection cooperation with ARQ in delay-tolerant wireless networks

Through automatic repeat request (ARQ) mechanism, additional diversity benefit can be obtained for delay-tolerant wireless networks. In this paper, we combine the distributed selection cooperation protocols with ARQ mechanism to develop more powerful cooperative schemes and analyze their performance from the perspective of diversity-multiplexing-delay (D-M-D) tradeoff. We prove that directly extending the selection cooperation protocol with single round of feedback to multiple rounds does not lead to optimal D-M-D tradeoff. Then we develop an improved scheme achieving the upper bound of D-M-D tradeoff and also propose an efficient scheme that greatly reduces the number of feedbacks and almost achieves the optimal performance. The D-M-D tradeoff analysis and simulation results demonstrate the significant performance improvement of all the proposed schemes.