Patent ID: 9641126
Date: 2017-05-02
CPC Classifications: H03D,H04B,H04L

Claim:
1. A method for in-phase-quadrature (I-Q) imbalance calibration, comprising: transmitting a signal by a first transmitter in a first system, the signal comprising a constant value; receiving the signal at a second receiver in a second system, wherein the first system and the second system are included in a same wireless communication device, and wherein the first system and the second system are different types of wireless systems; and estimating an I-Q imbalance for the second receiver based on the received signals, wherein estimating the I-Q imbalance comprises: measuring power on an in-phase branch and a quadrature branch, and measuring a cross-correlation between the in-phase branch and the quadrature branch, wherein a switch is configured to selectively couple the first transmitter in the first system to the second receiver in the second system during I-Q imbalance calibration, and wherein a first adder combines a transmit path of the first system and a transmit path of the second system, and a second adder is coupled to a receive path of the first system and a receive path of the second system, wherein the switch is coupled between the first adder and the second adder.