Csi feedback method and apparatus in large scale antenna system

A method used in a base station device of a large scale antenna system, comprising:

• receiving a first number and indication information of time-varying parameters of the first number of strong propagation paths, wherein the first number and the indication information are fed back by a user equipment (UE), and the time-varying parameters comprise:
• an arrival direction, time to arrive, and a path amplitude;
• and
• determining a downlink channel response according to the received indication information of the time-varying parameters of the first number of strong propagation paths.

An apparatus used in a user equipment (UE) of a large scale antenna system, comprising:

• a detection module, configured to detect a downlink channel;
• a calculation module, configured to determine, according to a multipath propagation model, a channel response of a first number of strong propagation paths, wherein the channel response of each propagation path is determined as a matrix related to the following time-varying parameters:
• an arrival direction, time to arrive, and a path amplitude;
• and
• a feedback module, configured to feed back the first number and indication information of the time-varying parameters of the first number of strong propagation paths.

An apparatus used in a base station device of a large scale antenna system, comprising:

• a receiving module, configured to receive a first number and indication information of time-varying parameters of the first number of strong propagation paths, wherein the first number and the indication information are fed back by a user equipment (UE), and the time-varying parameters comprise:
• an arrival direction, time to arrive, and a path amplitude;
• and
• a calculation module, configured to determine a downlink channel response according to the received indication information of the time-varying parameters of the first number of strong propagation paths.