Abstract: The present invention relates to a method for adjusting the amplification of a high frequency signal, a transmitter or receiver unit and a communication system. The aim of the invention is to provide a method and device for improved use of a polar-loop concept in a transmitter, especially for a mobile radio link. According to the method for adjusting the amplification of a high frequency signal, wherein the phase angle and the amplitude of an error-free input signal are separated from each other with a defined part of an output signal and readjusted, an output voltage of a battery voltage modulator is evaluated as a measure for an error at the output of a transmitter amplifier and taken into account in order to provide a correction.

Abstract: A circuit is provided for regulating operation of a transmitter of a mobile communication terminal, which runs in the EDGE and GMSK modulation modes.

Abstract: A PIN diode switching system is provided, particularly for the transmission stage of a mobile radio telephone, in which, when the PIN diode switching system is in a reverse-bias state, a PIN diode is isolated from its power supply via a high-impedance switch and is, thus, biased by its self-rectification to a radio-frequency voltage in order to suppress harmonic formation and radio-frequency attenuation.

Abstract: An RF power amplifier is disclosed having a measuring device to measure the operating current of the amplifier, where the measuring device presents a low load. The low load is achieved by the RF power amplifier divided into a main amplifier and a measuring amplifier, a RF useful signal to be amplified being applied to the main amplifier. The measuring amplifier has a transistor to whose base is applied the RF useful signal, and whose emitter is connected to ground via a measuring resistor to produce a measured voltage reproducing the operating current of the RF power amplifier. Matching circuitry matches a bias voltage of the second transistor to the bias voltage of the first transistor in order to set an operating point of the second transistor. A load is connected to the collector of the first transistor and to the collector of the second transistor.

Abstract: Disclosed is a circuit arrangement for regulating operation of a transmitter of a mobile communication terminal, which runs in the EDGE and GMSK modulation modes.

Abstract: The invention relates to a transceiver unit for operation at a first and second transmitting/receiving frequency. In particular, a transceiver unit for operation in different systems of mobile telecommunication, having exactly one power output stage for the first and second transmitting frequency, one receiving section having a first and a second input for the first and second receiving frequency, respectively, a transmitting/receiving antenna and a switchable filter element for optionally connecting the power output stage or, respectively, the first or second input of the receiving section to the transmitting/receiving antenna.