Patent ID: 6377620
Filing Date: 2002-04-23
Classification: H04L

Abstract:
A signal balancer for use in a quadrature phase shift keying system comprising:I and Q signal inputs, each said input coupled to first I and Q adjustable gain amplifiers, each said first amplifier having an output, said first I and Q amplifier outputs coupled to respective second I and Q adjustable gain amplifiers, each said second amplifier having an output; means for controlling each of said first I and Q amplifier gains including: I magnitude determining means and Q magnitude determining means coupled to said respective first I and Q amplifier outputs and to a magnitude comparator means; and said magnitude comparator means generating a gain correction signal for both of said first I and Q amplifiers, I and Q adders, each of said adders having a first adder input coupled to its respective first I and Q amplifier output, a second adder input coupled to said output of the different second amplifier, and a mixer output; and means for controlling each of said second I and Q amplifier gains including an I and Q cross correlation means coupled to said I and Q mixer outputs generating a cross correlation product; whereby, said I and Q adders output amplitude and phase balanced I and Q signals.