Abstract: In a circuit arrangement for regulating a DC signal component of a signal that is input to a frequency mixer, the regulation comprises a detector which detects the DC component of the input signal. A comparator compares the DC component with a reference value, and drives an apparatus for influencing the DC component based on the comparison.

Abstract: A power amplifier has at least a first amplifier circuit with an output port and at least a second amplifier circuit with an output port. The power amplifier further has at least a coupler with a first and a second input port and a first and a second output port. The first input port of the coupler is coupled with the output port of the first amplifier circuit and the second input port of the coupler is coupled with the output port of the second amplifier circuits. The power amplifier further has a switch with at least an input terminal and at least two output terminals. The input terminal of the switch is coupled with the first output port of the coupler, wherein each of the output terminals of the switch is connected with a respective terminal impedance, the terminal impedances having different impedance values.

Abstract: An amplifier circuit includes a first series circuit connected between a supply voltage and a reference potential. The first series circuit includes a current source, a first tap and a first component configured as a diode. The amplifier circuit also includes a second series circuit connected between the supply voltage and the reference potential, and includes a controlled path between a first connection and a second connection of a first transistor and a second tap. The control connection of the first transistor is coupled to the first tap. The second tap is used to output a bias voltage. The amplifier circuit includes an amplifier stage coupled to the second tap for setting an operating point of the amplifier stage.

Abstract: A circuit arrangement includes a plurality of type-identical and identically operated active components, or separate sections of an active component, and includes a branched wiring structure for the interconnection of component connections. In each case the wiring end portions lie between a branching point and an input of different components or sections, wherein the wiring end portions are formed with predetermined geometrical asymmetry with respect to one another in such a way that there is an electrical symmetry of the interconnection configuration between all the connected type-identical components or sections. More particularly, the impedance values between the branching point and the different inputs and outputs are substantially identical.

Abstract: A detection circuit includes a bias circuit configured to generate a first bias voltage and a second bias voltage. The detection circuit further includes a storage device configured to store a detection value corresponding to an amplitude of a radio frequency signal received at a detector input. A series connection of a first diode element and a second diode element includes first tap to receive the first bias voltage and the radio frequency signal, a second tap which is coupled to a connection node of the first and the second diode element to receive the second bias voltage and a third tap to provide the detection value.

Abstract: A power amplifier has at least a first amplifier circuit with an output port and at least a second amplifier circuit with an output port. The power amplifier further has at least a coupler with a first and a second input port and a first and a second output port. The first input port of the coupler is coupled with the output port of the first amplifier circuit and the second input port of the coupler is coupled with the output port of the second amplifier circuits. The power amplifier further has a switch with at least an input terminal and at least two output terminals. The input terminal of the switch is coupled with the first output port of the coupler, wherein each of the output terminals of the switch is connected with a respective terminal impedance, the terminal impedances having different impedance values.

Abstract: An amplifier circuit includes a first series circuit connected between a supply voltage and a reference potential. The first series circuit includes a current source, a first tap and a first component configured as a diode. The amplifier circuit also includes a second series circuit connected between the supply voltage and the reference potential, and includes a controlled path between a first connection and a second connection of a first transistor and a second tap. The control connection of the first transistor is coupled to the first tap. The second tap is used to output a bias voltage. The amplifier circuit includes an amplifier stage coupled to the second tap for setting an operating point of the amplifier stage.

Abstract: A power amplifier arrangement includes a power amplifier with an input for a radio-frequency signal and an output for delivering a second radio-frequency signal. The second radio-frequency signal has a current and a voltage. A second element is configured to deliver a first signal derived from the current of the second radio-frequency signal. Furthermore, a first element is provided to deliver a second signal derived from the voltage of the second radio-frequency signal. An evaluating circuit detects in-phase components of the first and the second signal. As a result, in-phase current and voltage components can be detected together which produce the active power of the second radio-frequency signal by multiplication.

Abstract: An apparatus and a method compare the output signal of a mixer in a detector with one of two input signals of the mixer, in order to compensate for the offset of a mixer or modulator. The detector determines the sign of the offset of the mixer. A compensation value is formed in an actuator unit by successive approximation. The value is transmitted to the mixer. In an advantageous embodiment of the invention, a simple phase detector (PD) is used to determine the offset sign (VZ). The above-described indirect measuring method functions with very high accuracy, even at only a very small offset. Offsets in the circuits preceding the mixer (MI1) are compensated for simultaneously. A manual or individual calibration of direct voltage offsets is therefore unnecessary.

Abstract: A circuit configuration for mixing a differential desired signal with a differential local oscillator signal includes two difference amplifiers which are controllable on the input side by the desired signal and cross-coupled on the output side. Currents flowing through the difference amplifiers are switched by the components of the local oscillator signal in alternation. The circuit makes a lower supply voltage possible, given the presence of only two transistor levels.

Abstract: A polar loop transmission circuit is proposed wherein a signal to be transmitted and a feedback signal are separated into their polar phase and amplitude components and the components are compared to one another for realizing a phase and amplitude modulation. An amplitude modulator controlled by an amplitude modulation signal is provided, whereby the amplitude modulator follows an oscillator and is preferably fashioned as a nonlinear amplifier that is operated in saturation. An amplifier attenuating the output signal of the amplitude modulator is provided in the feedback path. The present transmission architecture is suitable for future mobile radio telephone systems having a phase and amplitude modulation and are based on the known GSM standard, for example.

Abstract: A circuit arrangement for regulating a signal DC component is specified, which is connected to an input of a frequency mixer (1). The regulation comprises a common-mode signal component detector (5), which supplies the DC component of the input signal. A comparator (8) compares said DC component with a reference value and, depending on this, drives means for influencing the common-mode level (12). With the common-mode level regulation described, a radio frequency front end of analogue construction can be combined virtually arbitrarily with baseband chips in order to form a mobile radio transmitter. Moreover, temperature- and ageing-dictated drift effects are advantageously corrected.

Abstract: A frequency splitter circuit includes only two differential amplifiers. A clock input signal is supplied to clock signal inputs for activating the amplifiers. A respective signal of half the frequency of the clock input signal is derivable at main and auxiliary outputs. The differential amplifiers are cross-coupled. The frequency splitter circuit is operable with low supply voltage and provides high signal amplitudes at the output, high edge steepness, and low phase noise. The frequency splitter circuit can be utilized in high-frequency receivers, for example.

Abstract: An apparatus and a method compare the output signal of a mixer in a detector with one of two input signals of the mixer, in order to compensate for the offset of a mixer or modulator. The detector determines the sign of the offset of the mixer. A compensation value is formed in an actuator unit by successive approximation. The value is transmitted to the mixer. In an advantageous embodiment of the invention, a simple phase detector (PD) is used to determine the offset sign (VZ). The above-described indirect measuring method functions with very high accuracy, even at only a very small offset. Offsets in the circuits preceding the mixer (MI1) are compensated for simultaneously. A manual or individual calibration of direct voltage offsets is therefore unnecessary.

Abstract: A polar loop transmission circuit is proposed wherein a signal to be transmitted and a feedback signal are separated into their polar phase and amplitude components and the components are compared to one another for realizing a phase and amplitude modulation. An amplitude modulator controlled by an amplitude modulation signal is provided, whereby the amplitude modulator follows an oscillator and is preferably fashioned as a nonlinear amplifier that is operated in saturation. An amplifier attenuating the output signal of the amplitude modulator is provided in the feedback path. The present transmission architecture is suitable for future mobile radio telephone systems having a phase and amplitude modulation and are based on the known GSM standard, for example.

Abstract: A frequency splitter circuit includes only two differential amplifiers. A clock input signal is supplied to clock signal inputs for activating the amplifiers. A respective signal of half the frequency of the clock input signal is derivable at main and auxiliary outputs. The differential amplifiers are cross-coupled. The frequency splitter circuit is operable with low supply voltage and provides high signal amplitudes at the output, high edge steepness, and low phase noise. The frequency splitter circuit can be utilized in high frequency receivers, for example.

Abstract: A circuit configuration for mixing a differential desired signal with a differential local oscillator signal includes two difference amplifiers which are controllable on the input side by the desired signal and cross-coupled on the output side. Currents flowing through the difference amplifiers are switched by the components of the local oscillator signal in alternation. The circuit makes a lower supply voltage possible, given the presence of only two transistor levels.