Method, apparatus and system for uplink rank adaptation

摘要

A method, an apparatus and a system for uplink rank adaptation are provided in the present invention, wherein the method comprises: estimating the maximum supportable data rate and channel information of a user equipment in uplink transmission; comparing the maximum supportable data rate with one or more predetermined thresholds, wherein the predetermined thresholds are associated with corresponding ranks; and determining a rank used by the user equipment in the uplink transmission based on a result of the comparison and the estimated channel information. With the present invention, a base station can quickly determine a rank for uplink MIMO transmission, decrease the rank estimating error, and lower the computation complexity for estimating the rank and the subsequent pre-coding vector.

主权项

1. A method for uplink rank adaptation, comprising:
estimating a maximum supportable data rate and channel information of a user equipment in uplink transmission, wherein the maximum supportable data rate is estimated based on an estimation of uplink power headroom, transmit buffer status and an uplink transmission grant received from the user equipment; comparing the maximum supportable data rate with one or more predetermined thresholds, wherein the predetermined thresholds are associated with corresponding ranks; determining a rank used by the user equipment in the uplink transmission based on a result of the comparison and the estimated channel information; and using the rank for wireless communication of the user equipment in the uplink transmission, wherein the estimation of uplink power headroom is based on a reference uplink power headroom, which is updated by a base station; in response to measuring the uplink power headroom of the user equipment, updating the reference uplink power headroom based on a formula below:TPO=∑c=1N⁢rxPowerPCH,c/rxPowerR-DPCCH where TPO is a transmission power offset of a user equipment; N is a number of physical channels in the uplink; rxPowerPCH,c is received power of the Cth physical channel; and rxPowerR-DPCCH is received power of a reference dedicated physical control channel of the uplink power headroom.