On the Performance of Wireless Ad Hoc Networks Using Amplify-and-Forward Cooperative Diversity

We analyze wireless ad hoc networks that use cooperative diversity from two complementary perspectives. The network we consider uses the amplify-and-forward (AF) cooperation protocol. We first determine the capacity region and rate matrices for these networks. Numerical results indicate that cooperation is beneficial when optimal multi-hop routing is not used, but can be ineffective when optimal multi-hop routing is employed. Secondly, we develop an analytical expression for the transmission blocking probability (TBP). The TBP allows us to draw insight into the possible benefits of cooperation. We determine that the TBP for networks that use cooperation is not noticeably larger than that for networks that employ only point-to-point communications. Taken together, these two results leads us to conclude that although the blocking probability does not significantly increase when cooperation is used, the capacity is only increased in certain scenarios, i.e. when optimal multi-hop routing is not used