Radio communication system, radio base station apparatus, user terminal and radio communication method

摘要: To reduce overhead of CSI feedback without decreasing throughput in applying CoMP transmission, a radio communication method the invention is characterized by including, user terminal measuring quality information for each cells to perform Coordinated Multi-Point and notifying base station apparatus information, calculating difference between using from terminal, determining granularity inter-cell channel state based on difference, granularity, and, that generating according apparatus, transmitting apparatuses transmission.