Coded cooperation under slow fading, fast fading, and power control

Abstract

User cooperation provides uplink transmit diversity even when mobile units cannot accommodate multiple antennas due to size constraints. Recently, a versatile user cooperation method called coded cooperation diversity was introduced, in which standard channel coding methods are used to implement cooperation. This method achieves remarkable gains compared to a conventional (non-cooperative) system while maintaining the same information rate and transmit power. In this work, we investigate the performance of coded cooperation under a variety of conditions. We investigate slow Rayleigh fading scenarios where the users have either similar or significantly different quality channels to the base station. We compare coded cooperation with the amplify-and-forward protocol proposed by Laneman, Wornell, and Tse. Furthermore, we consider the effects of conventional power control on cooperating users for the slow fading case. Finally, we present some results for the case of fast Rayleigh fading.