Patent ID: 7366247

Claim:
An apparatus for selecting one of an open-loop first transmit antenna diversity scheme and closed-loop second transmit antenna diversity schemes by a user equipment (UE) in a system including a Node B transmitter which includes at least two antennas and uses the first transmit antenna diversity scheme for transmitting space time transmit diversity (STTD)-encoded signals via the antennas and the second transmit antenna diversity scheme for controlling a phase of signals transmitted from the antennas in response to feedback information including relative phase difference information of the antennas from the UE, the apparatus comprising: a channel estimator for receiving a first channel signal from the Node B transmitter, and estimating a channel response from the received first channel signal; a determiner for estimating a variation speed of the first channel based on the estimated channel response, and selecting one of the first and second transmit antenna diversity schemes according to the estimated variation speed of the first channel; and an information generator for generating information indicating the selected transmit antenna diversity scheme.