Multiple-access capabilities of AF relaying with zero forcing
Abdurrahman Alfitouri, Khairi Ashour Hamdi · 2016
In this paper, we explore the multiple access capabilities of amplify and forward (AF) gateways employing zero forcing (ZF) beamforming techniques in a space division multiple access (SDMA) scenario. A random number of users are isolated from their destination, and the only mean to communicate with their destination(s) is through the AF gateway equipped with multiple antennas, and employing ZF beamforming technique. The channels experience both small and large-scale fading. New exact analytical expressions are derived for the overall spectral efficiency (SE) in the collaborative and non-collaborative scenarios, where in the first case ZF is applied at the sources and destinations, whereas in the latter case ZF is implemented at the gateway. The new results is used to investigate the impact of different system parameters into the overall efficiency of ZF gateways. The accuracy of the new results is confirmed through comparison with Monte Carlo simulations.