The time-division duplex(TDD)largescale antenna array system using analog-digital hybrid beamforming precoding technique has a very broad application prospect in the field of 5G/6G mobile communications.However,the ga...The time-division duplex(TDD)largescale antenna array system using analog-digital hybrid beamforming precoding technique has a very broad application prospect in the field of 5G/6G mobile communications.However,the gain imbalance between radio frequency(RF)channels introduced by RF devices leads to problems such as decreased channel estimation accuracy,deviation of precoding beam direction,and high side-lobe level.Meanwhile,the RF transceiver gain asymmetry destroys the symmetry of the uplink and downlink channels of the system,leading to a sharp performance degradation of the TDD system that employs the uplink channel information for the downlink beamforming precoding.In this paper,we propose an innovative and low-cost hardwarebased self-calibration method to solve the above two problems simultaneously.The calibration is divided into two stages:digital beamforming chain calibration(DBCC)and analog beamforming transceiver calibration(ABTC).Simulation results demonstrate that this approach simultaneously enhances the accuracy of both channel estimation and beamforming precoding,significantly improving the achievable data rate of existing precoding schemes.Furthermore,it offers considerable computational complexity advantages over current over-the-air(OTA)approaches.展开更多
基金supported by National Natural Science Foundation of China(No.61971063)Key Project of Science and Technology Research of Henan Provincial Department of Education(No.24B510002)Natural Science Project of Zhengzhou Bureau of Science and Technology(No.22ZZRDZX40).
文摘The time-division duplex(TDD)largescale antenna array system using analog-digital hybrid beamforming precoding technique has a very broad application prospect in the field of 5G/6G mobile communications.However,the gain imbalance between radio frequency(RF)channels introduced by RF devices leads to problems such as decreased channel estimation accuracy,deviation of precoding beam direction,and high side-lobe level.Meanwhile,the RF transceiver gain asymmetry destroys the symmetry of the uplink and downlink channels of the system,leading to a sharp performance degradation of the TDD system that employs the uplink channel information for the downlink beamforming precoding.In this paper,we propose an innovative and low-cost hardwarebased self-calibration method to solve the above two problems simultaneously.The calibration is divided into two stages:digital beamforming chain calibration(DBCC)and analog beamforming transceiver calibration(ABTC).Simulation results demonstrate that this approach simultaneously enhances the accuracy of both channel estimation and beamforming precoding,significantly improving the achievable data rate of existing precoding schemes.Furthermore,it offers considerable computational complexity advantages over current over-the-air(OTA)approaches.