Delay–Interleaved Cooperative Relay Networks

In this letter, we propose a novel system design for implementing distributed space-time codes (DSTCs) in order to improve the performance of the codes. The proposed method called delay and interleaved cooperative relay networks manages to force transmitted signals to experience different channel fading coefficients as much as possible, which increases the coding gain or even, in some cases, the diversity order of the codes. The only degradation to the conventional system is a small delay that is negligible in many communication applications. There are no extra computational complexities burdened to the relays, and only a simple permutation is performed at the relays and the destination. Simulation results also confirm the performance superiority of this innovative method over the conventional DSTC system.