Stochastic Geometry Analysis of Coordinated Beamforming Small Cell Networks With CSI Delay

This letter characterizes the performance of coordinated beamforming (CBF) in frequency division duplex systems with user-centric clustering in the presence of channel state information (CSI) delay, which is modeled by Gauss–Markov auto-regressive model. A downlink model based on stochastic geometry is put forth to the analysis of statistical performance. Using the tools of stochastic geometry, the approximate expression for the average data rate of users is derived in terms of relevant system parameters. The tightness of the approximate expression is verified by Monte Carlo simulations. The approximate expression can be used to determine the optimal coordinated range. We further investigate the impact of CSI delay on the performance of CBF systems.