Patent ID: 7020216
Filing Date: 2006-03-28
Classification: H03F,H04L

Abstract:
1. A method for adjusting a phase angle of a phase modifier of a transmitting device, wherein said method comprises: providing the transmitting device comprising: a first differential amplifier, connected upstream the quadrature modulator, said first differential amplifier having a first input supplied by the inphase component of the complex input signal and a second input supplied by the fedback inphase component; a second differential amplifier, connected upstream the quadrature modulator, said second differential amplifier having a first input of the second differential amplifier supplied by the quadrature phase component of the complex input signal and a second input of the second differential amplifier supplied by the fedback quadrature phase component; and a phase modifier, which supplies to the quadrature demodulator an oscillator signal, shifted with regard to an oscillator signal supplied to the quadrature modulator by the phase angle to be adjusted; applying an input signal with a predetermined constant inphase component and a predetermined constant quadrature phase component at each transmitting interval with a closed feedback loop containing the quadrature modulator, the power amplifier, the quadrature demodulator, the first differential amplifier and the second differential amplifier; measuring the quadrature phase component and optionally the inphase component at a first measuring point behind an output of the first differential amplifier and a second measuring point behind an output of the second differential amplifier; determining a phase correction value based on the measured quadrature phase component and optionally the measured inphase component; and correcting the currently set phase angle of the phase modifier by adding or subtracting the determined phase correction value in a transmitting interruption interval, wherein the phase angle is not altered if the amount of the measured quadrature phase component is smaller than a predetermined limit value.