Patent ID: 8731480
Filing Date: 2014-05-20
Classification: H04B

Abstract:
1. A method for transmitting feedback control information at a mobile station (MS) in a wireless communication system using a cooperative Multiple-Input Multiple-Output (MIMO) mode, the method comprising: determining, by the mobile station, to transition to the cooperative MIMO mode; transmitting, by the mobile station, control information requesting the cooperative MIMO mode to a serving base station; receiving, by the mobile station from the serving station, Precoding codebook Matrix Index (PMI) information including PMI restriction lists for respective frequency bands allocated to the serving base station, when the MS is located at boundary of a cell managed by the serving base station, wherein the PMI restriction lists indicate available predetermined PMIs for the mobile station inside a cell of a neighbor base station; selecting, by the mobile station, a transmission path between the MS and one or more cooperative base station for transmitting precoding-related feedback control information to the one or more cooperative base stations operating in the cooperative MIMO mode, wherein the transmission path is at least one of a first path running through a serving base station, a second path running directly to the one or more cooperative base station, and a third path running via a relay station; transmitting, by the mobile station, the precoding-related feedback control information to the one or more cooperative base stations through the selected transmission path; and receiving, by the mobile station, data from the one or more cooperative base stations, to effect at least one of spatial diversity and spatial multiplexing wherein the precoding-related feedback control information is transmitted by using an orthogonal code specific to the one or more base station, when the precoding-related feedback control information is transmitted via the second path.