Method of reducing signal imbalance in wireless communication system

摘要

Multiplier coefficients are updated according to minimal power value of mixed signals in a wireless communication system. While using updated multiplier parameters, signal imbalance caused by a local oscillator or mismatch between analog elements of the wireless communication system can be reduced, so that the wireless communication system can be immune from noises.

主权项

1. A method of reducing signal imbalance in a transmitter of a wireless communication system, comprising:
inputting a first single-tone signal having a first frequency to the transmitter for generating a first single-tone modulated signal and inputting a second single-tone signal having a second frequency to the transmitter for generating a second single-tone modulated signal, wherein a sum of the first frequency and the second frequency is zero, and the first frequency is higher than the second frequency; inputting the first single-tone modulated signal to a self-mixer of the transmitter for generating a first mixed signal, and inputting the second single-tone modulated signal to the self-mixer for generating a second mixed signal; determining a first multiplier coefficient and a second multiplier coefficient corresponding to a first minimal power value of the first mixed signal at a third frequency according to the first minimal power value, and determining a third multiplier coefficient and a fourth multiplier coefficient corresponding to a second minimal power value of the second mixed signal at a fourth frequency according to the second minimal power value, wherein the third frequency is equal to a double of the first frequency, and the fourth frequency is equal to a double of the second frequency; re-inputting the first single-tone signal to the transmitter, and processing the first single-tone signal at the transmitter using the first multiplier coefficient and the second multiplier coefficient for determining a third minimal power value at a fifth frequency at a receiver of the wireless communication system, and determining a fifth multiplier coefficient and a sixth multiplier coefficient corresponding to the third minimal power value, wherein the fifth frequency is equal to half of the fourth frequency; the transmitter utilizing a constant multiplier coefficient and a seventh multiplier coefficient, and the receiver utilizing the fifth multiplier coefficient and the sixth multiplier coefficient, wherein the seventh multiplier coefficient is equal to half of a sum of the second multiplier coefficient and the fourth multiplier coefficient; and inputting a multi-tone signal at the transmitter, and performing a frequency-domain least mean square algorithm according to the multi-tone signal, for updating a plurality of first multi-tap finite impulse time-domain coefficients into a plurality of second multi-tap finite impulse time-domain coefficients.