Abstract :
The paper describes an antenna path calibration method for (Multiple Input Multiple Output) MIMO systems. In a MIMO system, the RF components used at each transmit/receive antenna path, i.e., uplink versus downlink, do not exhibit similar phase and amplitude responses. Hence, if uplink measurements are used for downlink operations such as beamforming, the incurred distortion results in performance degradation. The proposed scheme relies only on the existing uplink measurements performed by the base-station, and then it provides a feedback to the UE for calibration. It is shown that the overall scheme can be employed for both TDD and FDD systems.
Keywords :
Long Term Evolution; MIMO systems; calibration; frequency division multiplexing; receiving antennas; time division multiplexing; transmitting antennas; FDD; Long Term Evolution; MIMO systems; TDD; UE calibration; amplitude response; antenna path calibration; base station; frequency division multiplexing; multiple input multiple output systems; performance degradation; phase response; receive antenna path; time division multiplexing; transmit antenna path; uplink measurements; user equipment; Calibration; Channel estimation; Covariance matrix; Downlink; MIMO; Signal to noise ratio;
