Performance of User-specific Transmission Mode Selection in Frequency Division Duplex Coordinated Multi-point Systems

Coordinated multi-point(CoMP) transmission has draw broad attention due to its advantage of improving the performance of cell-edge users. According to the information exchanged among base stations, the base station cooperative strategies can be roughly divided into joint processing and coordinated beamforming. Each user selects the transmission mode for the base stations in the cooperative cluster, including joint processing, coordinated beamforming and non-CoMP. In this paper we analyze the performance of transmission mode selection at the user in percell codebook based CoMP systems with phase ambiguity feedback. By deriving the lower bound of average SINR and analyze the performance of the users with specific location, we find the performance of base stations participating cooperation is better than that of non-CoMP, and the bits of phase ambiguity determines which cooperative strategy should be selected. When the number of bits is large, all the base stations should participate joint processing, otherwise they will join coordinated beamforming, which is still true for the user with general location as shown by simulations.