Patent ID: 7633994

Claim:
A method for compensating for in-phase and quadrature (I/Q) imbalances in a multiple antenna system (MAS) with multi-user (MU) transmissions (“MU-MAS”) comprising: transmitting a training signal from each antenna of a base station to each of a plurality of wireless client devices, each of the client devices analyzing each training signal to generate channel characterization data, and receiving the channel characterization data at the base station; computing a plurality of MU-MAS precoder weights based on the channel characterization data, the MU-MAS precoder weights calculated to pre-cancel interference due to I/Q gain and phase imbalances and/or inter-user interference; precoding data using the MU-MAS precoder weights to generate precoded data signals for each antenna of the base station; and transmitting the precoded data signals through each antenna of the base station to each respective client device; wherein the MU-MAS system is a distributed-input distributed-output (DIDO) communication system and wherein the MU-MAS precoder weights are DIDO precoder weights; and wherein the precoder weights are calculated to cancel inter-user interference but not inter-carrier interference (“ICI”) and wherein the client wireless client devices include receivers with filters for cancelling the ICI.