Patent ID: 7555051

Claim:
A communications device comprising: at least one pair of channels (I, Q), each channel of the at least one pair of channels (I, Q) including: a mixer having a data input from an amplifier and a local oscillator input, at least one quadrature phase generator that is configured to: provide a first output at a first phase, and provide a second output at a second phase that is substantially ninety degrees apart from the first phase, wherein a phase imbalance is associated with the mixer and the at least one quadrature phase generator and a gain imbalance is associated with the amplifier, at least one switch that is configured to: couple the first output to the local oscillator input of the mixer in a first channel of the at least one pair of channels (I, Q) and the second output to the local oscillator input of the mixer in a second channel of the at least one pair of channels (I, Q), when the switch is in a first mode, and couple the second output to the local oscillator input of the mixer in the first channel and the first output to the local oscillator input of the mixer in the second channel, when the switch is in a second, and a controller that isolates the gain imbalance and the phase imbalance by selectively placing the switch into the first mode and the second mode to independently measure the gain imbalance and the phase imbalance for the first channel and the second channel.