Transmitter and receiver gain calibration by means of feedback in a transceiver

摘要

The invention relates to gain calibration in a transceiver unit ( 100 ) having a transmitter unit and a receiver unit and a feed back coupling ( 165 ) between these. A signal level measurement unit ( 163 ) measures signal levels of a feedback signal through either the receiver unit or through a signal level detector ( 167 ). A reference signal level of the feedback signal is set by adjusting the transmitter until the signal level measurement unit ( 163 ) measures a predefined value when connected through the signal level detector ( 167 ). An absolute value of the transmitter gain is then calibrated. The signal level measurement unit ( 163 ) is connected through the receiver unit and the absolute gain of the receiver is calibrated. A gain is changed either in the receiver or the transmitter unit. The relative signal level change of the feedback signal is measured and used to calibrate the gain step.