Patent ID: 7236540

Claim:
A method of channel estimation in a transmission diversity system, comprising: observing phase differences between channel estimates in the transmission diversity system by performing the sub-steps of; determining whether a phase shift is in a right-half plane or a left-half plane and then calculating a left/right estimate, wherein the step of calculating the left/right estimate comprises comparing a value based on the channel estimates to a threshold based on a previous left/right command; and determining whether the phase shift is in a lower-half plane or an upper-half plane and then calculating an up/down estimate, wherein the step of calculating the up/down estimate comprises comparing a value based on the channel estimates to a threshold based on a previous up/down command; estimating the transmitted phase using results of the sub-steps of calculating the left/right estimate and the up/down estimate; and updating a previous left/right estimate or a previous up/down estimate using channel estimates for a current slot and a corresponding previous slot.