Iterative MMSE interference canceler for cooperative diversity MIMO relay network
Abstract
In multiple-input multiple-output (MIMO) relay network relaying at the relay nodes is performed during two phases: broadcasting phase and cooperative phase known as multiple access phase. The main question is, which is the best receiver able to increase the distributed diversity gain in MIMO relay network for spatial multiplexing (SM) scheme and time division multiple access (TDMA) or multi-carrier multiple access (MC MA). In this paper, we apply an iterative minimum mean squared error (MMSE) interference canceller (IC-MMSE) for MIMO relay network. This receiver detects the transmitted symbols from each antenna using iterative process including interference canceller, MMSE filter and maximum a posteriori (MAP) decoder. Under the assumption of the orthogonality of the forwarding channels, case of TDMA or MC MA, we derive a closed form expression of the instantaneous capacity of the MIMO relay network. We evaluate also the system performances in terms of bit error rate (BER) versus the number of relays K and the signal to noise ratio (SNR) measured at the destination.