Beamforming with phase compensation

摘要

A method and a base station for phase compensation in beamforming in a multi-antenna Time Division Duplex (TDD) communication network. In a first transmission mode, the base station estimates a first phase shift between a first antenna port and a reference antenna port in uplink based on a measurement of a first Sounding Reference Signal (SRS). Then the base station estimates in the first transmission mode a second phase shift between the first antenna port and the reference antenna port in downlink based on a Channel State Information (CSI) feedback from a User Equipment (UE), and calculates a parameter indicative of a difference between the first phase shift and the second phase shift.

主权项

1. A method in a base station for phase compensation in beamforming in a multi-antenna Time Division Duplex (TDD) communication network, comprising the steps of:
estimating, in a first transmission mode, a first phase shift between a first antenna port Ni (i=1, . . . , M−1) and the reference antenna port N0 in uplink (φ+θ) based on a measurement of a first Sounding Reference Signal (SRS); estimating, in the first transmission mode, a second phase shift between the first antenna port Ni and the reference antenna port N0 in downlink (φ+ξ) based on a channel state information (CSI) feedback from a User Equipment (UE); calculating a parameter (Δ) indicative of a difference between the first phase shift (φ+θ) and the second phase shift (φ+ξ); estimating, in a second transmission mode, a third phase shift between the first antenna port Ni and the reference antenna port N0 in uplink (φ′+θ) based on a measurement of a second SRS; calculating, in the second transmission mode, a fourth phase shift between the first antenna port Ni and the reference antenna port N0 in downlink (φ′+ξ) as a difference between the third phase shift (φ′+θ) and the parameter (Δ); and compensating, in the second transmission mode, the phase of input signal on the first antenna port Ni by the fourth phase shift (φ′+ξ) for beamforming.