Patent ID: 7031669

Claim:
A radio device comprising: a. a plurality of transmitters that upconvert corresponding ones of a plurality of baseband transmit signals for simultaneous transmission via corresponding ones of a plurality of antennas; b. a plurality of receivers that downconvert a plurality of radio signals detected by corresponding ones of the plurality of antennas to produce a corresponding plurality of baseband receive signals; and c. a processor coupled to the plurality of transmitters and the plurality of receivers, wherein the processor measures differences in phase responses among the plurality of transmitters and plurality of receivers by measuring a first phase difference between an input to a transmitter associated with a first antenna and an output of a receiver associated with antenna i, and a second phase difference between an input to a transmitter associated with antenna i and an output of a receiver associated with the first antenna, for i=2 to N, where N is the number of antennas, and the processor processes the plurality of baseband transmit signals and/or the plurality of baseband receive signals with corresponding correction values that correct for differences in broadband phase responses among the plurality of transmitters and plurality of receivers.