Average Bit Error Rate and Sum Capacity in Heterogeneous Cloud Radio Access Networks

The performance analysis under various precoding strategies in heterogeneous cloud radio access networks (H-CRANs) is increasingly highlighted. In this paper, we focus on suppressing the inter-tier interference between macro base stations (MBSs) and remote radio heads (RRHs), which is severely affected by the application of precoding schemes. Two precoding schemes including interference cancelation (IC) and beamforming (BF) are characterized for performance evaluation. The average bit error rate (BER) and system sum capacity under these two schemes are derived with closed-form expressions. Monte Carlo simulations are performed to verify our analytical results and demonstrate the effectiveness of precoding schemes. Furthermore, we explore this problem analytically and demonstrate that BF is preferred when the signal-to-noise ratio (SNR) of MBSs is relatively low and IC outperforms BF at the high SNR region.