A TRANSMITTER AND A METHOD OF CALIBRATING POWER IN SIGNALS OUTPUT FROM A TRANSMITTER

摘要

A transmitter circuit (10) with a first characteristic controllable by a first control signal and a second characteristic controllable by a second control signal is calibrated using a calibration method to enable accurate power control. The transmitter circuit (10) will typically comprise a VGA amplifier (16) and a power amplifier (22). Typically, the gain of the VGA amplifier 16 is controlled and so is the current supplied to the power amplifier (22). The method comprises a number of operations including defining a set of multiple signal values for the first control signal, setting the first control signal to a level corresponding to a signal value from the set of multiple first control signal values. Then the second control signal is adjusted to cause the transmitter to operate in a desired manner and the power in a signal transmitted by the transmitter is measured. The setting, adjusting and measuring is repeated for each signal value in the set of multiple first control signal values.