Multiuser Zero-Forcing Beamforming With Limited Feedback in Wireless Ad Hoc Networks
The effect of limited feedback on point-to-multipoint communication is investigated in multi-antennas wireless ad hoc networks. The authors consider zero-forcing beamforming with quantized channel direction information and derive new closed-form expressions for the outage probability, throughput, transmission capacity, and average user rate. Expressions for the performance degradation due to finite rate feedback, the optimal number of streams, and the required feedback resolution are provided. The results indicate that the optimized system operating points depend on different network parameters such as pathloss exponent, signal-to-noise ratio, and node density.