Patent ID: 9344164
Filing Date: 2016-05-17
CPC Classification: H04B

Claim Text:
1. A method for feeding back a Pre-coding Matrix Indicator, PMI, wherein the method comprises: determining PMIs to be fed back including horizontal PMIs and vertical PMIs, or horizontal and vertical joint PMIs; and feeding back the determined PMIs in a non-periodical Channel State Information, CSI, feedback mode or a periodical CSI feedback mode; wherein in a case that the PMIs comprise horizontal PMIs and vertical PMIs; and in the periodical CSI feedback mode, the horizontal PMIs and the vertical PMIs are fed back only in the same sub-frame; the horizontal PMIs and the vertical PMIs are fed back in the same sub-frame or different sub-frames; or the horizontal PMIs and the vertical PMIs are fed back only in different sub-frames; wherein if the horizontal PMIs and the vertical PMIs are fed back only in the same sub-frame in the periodical CSI feedback mode, then the horizontal PMIs and the vertical PMIs are fed back in the same sub-frame together with corresponding Channel Quality Indicators, CQIs; wherein the horizontal PMIs and the vertical PMIs are fed back in the same sub-frame or different sub-frames in the periodical CSI feedback mode; and if the horizontal PMIs and the vertical PMIs are fed back in the same sub-frame, then there is also corresponding CQI information in the sub-frame in which the horizontal PMIs and the vertical PMIs are fed back, and if the horizontal PMIs and the vertical PMIs are fed back in different sub-frames, then there is also corresponding CQI information in the sub-frame in which the horizontal PMIs are fed back and/or corresponding CQI information in the sub-frame in which the vertical PMIs are fed back, wherein CQIs corresponding to the horizontal PMIs are determined from the horizontal PMIs, or the horizontal PMIs and the vertical PMIs; and CQIs corresponding to the vertical PMIs are determined from the vertical PMIs, or the horizontal PMIs and the vertical PMIs; wherein if the horizontal PMIs and the vertical PMIs are fed back only in different sub-frames in the periodical CSI feedback mode, then there is also corresponding CQI information in the sub-frame in which the horizontal PMIs are fed back and/or there is also corresponding CQI information in the sub-frame in which the vertical PMIs are fed back, wherein CQIs corresponding to the horizontal PMIs are determined from the horizontal PMIs, or the horizontal PMIs and the vertical PMIs; and CQIs corresponding to the vertical PMIs are determined from the vertical PMIs, or the horizontal PMIs and the vertical PMIs.