Patent ID: 9154210
Filing Date: 2015-10-06
Classification: H04B

Abstract:
1. A downlink transmission method for a Multiple Input Multiple Output (MIMO) system, the method comprising: selecting, by a base station, one downlink MIMO mode in a downlink transmission mode in which a User Equipment (UE) currently is, by using a Channel Quality Indicator (CQI), a Rank Indicator (RI) and a Preceding Matrix Indicator (PMI), which are reported by the UE within a time window; and transmitting, by the base station, data to the UE by using the selected downlink MIMO mode; wherein selecting the downlink MIMO mode in the downlink transmission mode in which the UE currently is, by using the CQI, the RI and the PMI, which are reported by the UE within the time window comprises: calculating a channel Signal Interference Noise Ratio (SINR) parameter of the UE by using the CQI that is reported by the UE within the time window; calculating a channel correlation parameter of the UE by using the RI that is reported by the UE within the time window; calculating a channel variation state parameter of the UE by using the PMI that is reported by the UE within the time window; and determining the downlink MIMO mode in the downlink transmission mode in which the UE currently is according to the channel SINR parameter, the channel correlation parameter and the channel variation state parameter of the UE; wherein determining the downlink MIMO mode in the downlink transmission mode in which the UE currently is according to the channel SINR parameter, the channel correlation parameter and the channel variation state parameter of the UE comprises: