Abstract: There is disclosed an amplifier circuit comprising: an amplifier having input and output terminals; a temperature dependent variable impedance unit comprising: a first terminal, a second terminal and a variable impedance unit control terminal; a transistor comprising a transistor control terminal coupled to the variable impedance unit control terminal; a first resistor coupled in parallel with the conduction channel; a capacitor coupled in series with the conduction channel between the conduction channel and one of: the first terminal; and the second terminal; and wherein: the first terminal is coupled to one of: the input terminal and the output terminal; the second terminal is for coupling to a reference node; and the variable impedance unit control terminal is configured to receive a control signal that is based on a measured temperature indicative of a temperature of the amplifier circuit and thereby provide a temperature dependent variable impedance for the amplifier circuit.

Abstract: A transmitter circuit includes a power amplifier and a mixer calibration circuit. The power amplifier provides a transmission signal. The mixer calibration circuit receives an incident signal of the transmission signal and a reflected signal of the transmission signal. Based on an amplitude of the reflected signal and on a phase difference between the incident and reflected signals, the mixer calibration circuit determines an amplitude of a standing wave signal.

Abstract: An amplifier circuit comprising: an amplifier; an output limiter for providing a variable impedance comprising: a first and second limiter terminal; a transistor comprising a conduction channel; a first resistor coupled in parallel with the conduction channel; and a capacitor coupled in series with the conduction channel between the conduction channel and the first or second limiter terminal; and a feedback control unit comprising a comparator block configured to provide a control signal to the output limiter based on a comparison of the amplifier output signal and a setting voltage; wherein: the first limiter terminal is coupled to the amplifier input or output; the second limiter terminal receives a reference voltage; and wherein receipt of the control signal at the transistor provides for a variable impedance for the amplifier circuit dependent on the amplifier output signal.

Abstract: A first input signal that corresponds to an output transmitted signal of a power amplifier of a vehicle radar system is received and the output power level of the transmitted signal is calibrated to optimize quality of the transmitted signal at the antenna reference plane (ARP). The proposed calibration method and apparatus allows to improve the output power calibration accuracy at ARP by compensating for reflected power at power amplifier output. The proposed apparatus uses the coupled and the isolated outputs of a bi-directional coupler to compensate the mismatch between the output of the power amplifier and the ARP; detectors at both coupler outputs measure both powers (coupled, isolated output) and apply respective correction on the calibration target to compensate for reflected power.

Abstract: In accordance with a first aspect of the present disclosure, a tunable attenuator is provided, comprising: one or more transformer windings configured to facilitate attenuating a signal; one or more conductive loops provided underneath the transforming windings; a controller configured to control an amount of current flowing through the conductive loops, thereby providing a tunable attenuation of said signal. In accordance with a second aspect of the present disclosure, a corresponding method of producing a tunable attenuator is conceived.

Abstract: A transceiver includes a transmitter, a frequency synthesizer coupled to the transmitter, a receiver coupled to the frequency synthesizer and a voltage sensor; and a digital controller coupled to the voltage sensor, the receiver, and the transmitter, wherein based on a DC voltage measurement of an IF signal made by the voltage sensor, a relative phase adjustment occurs of a relative phase associated with a local oscillator (LO) port and a radio frequency (RF) port of the receiver.

Abstract: There is disclosed an amplifier circuit comprising: an amplifier having input and output terminals; a temperature dependent variable impedance unit comprising: a first terminal, a second terminal and a variable impedance unit control terminal; a transistor comprising a transistor control terminal coupled to the variable impedance unit control terminal; a first resistor coupled in parallel with the conduction channel; a capacitor coupled in series with the conduction channel between the conduction channel and one of: the first terminal; and the second terminal; and wherein: the first terminal is coupled to one of: the input terminal and the output terminal; the second terminal is for coupling to a reference node; and the variable impedance unit control terminal is configured to receive a control signal that is based on a measured temperature indicative of a temperature of the amplifier circuit and thereby provide a temperature dependent variable impedance for the amplifier circuit.

Abstract: An amplifier circuit comprising: an amplifier; an output limiter for providing a variable impedance comprising: a first and second limiter terminal; a transistor comprising a conduction channel; a first resistor coupled in parallel with the conduction channel; and a capacitor coupled in series with the conduction channel between the conduction channel and the first or second limiter terminal; and a feedback control unit comprising a comparator block configured to provide a control signal to the output limiter based on a comparison of the amplifier output signal and a setting voltage; wherein: the first limiter terminal is coupled to the amplifier input or output; the second limiter terminal receives a reference voltage; and wherein receipt of the control signal at the transistor provides for a variable impedance for the amplifier circuit dependent on the amplifier output signal.

Abstract: A transceiver includes a transmitter, a frequency synthesizer coupled to the transmitter, a receiver coupled to the frequency synthesizer and a voltage sensor; and a digital controller coupled to the voltage sensor, the receiver, and the transmitter, wherein based on a DC voltage measurement of an IF signal made by the voltage sensor, a relative phase adjustment occurs of a relative phase associated with a local oscillator (LO) port and a radio frequency (RF) port of the receiver.

Abstract: A frequency drift detector includes a frequency-to-voltage converter, FVC, arranged to receive a reference frequency signal and configured to generate an FVC output voltage. The frequency drift detector also includes a voltage regulator arranged to output at least one regulated voltage; and a voltage comparator coupled to an output of the FVC and an output of the voltage regulator. The voltage comparator is arranged to compare the FVC output voltage and the at least one regulated voltage and generate an error signal in response to determining that the FVC output voltage exceeds a frequency drift level indicated by the at least one regulated voltage.

Abstract: A charge pump driver circuit (320) arranged to output a charge pump control signal (325). The charge pump driver circuit (320) includes a bias current source component (330) arranged to generate a bias current (335), a control stage (340) and an output stage (350). The control stage (340) is coupled to the bias current source component (330) and arranged to receive the bias current (335). The control stage (340) is further arranged to receive an input signal (215) and to generate a control current signal (345) proportional to the bias current (335) in accordance with the input signal (215). The output stage (350) is arranged to receive the control current signal (345) generated by the control stage (340) and to generate the charge pump control voltage signal (325) based on the control current signal (345) generated by the control stage (340). The bias current source component (330) is arranged to vary the bias current (335) in response to variations in temperature.

Abstract: A charge pump driver circuit comprises an output stage and a current generator component. The output stage is arranged to receive at an input node thereof a control current signal and comprises a resistance network coupled between the input node thereof and a reference voltage node and arranged to provide a resistive path through which the control current signal flows. The output stage is arranged to generate at an output node thereof a charge pump control voltage signal based on the voltage level at the input node thereof. The current generator component is arranged to receive an indication of a voltage level of a charge pump output signal, and to generate a feedback current dependent on the voltage level of the output signal, wherein the feedback current is injected into the resistive path of the resistance network through which the control current signal flows.

Abstract: A charge pump driver circuit comprises an output stage and a current generator component. The output stage is arranged to receive at an input node thereof a control current signal and comprises a resistance network coupled between the input node thereof and a reference voltage node and arranged to provide a resistive path through which the control current signal flows. The output stage is arranged to generate at an output node thereof a charge pump control voltage signal based on the voltage level at the input node thereof. The current generator component is arranged to receive an indication of a voltage level of a charge pump output signal, and to generate a feedback current dependent on the voltage level of the output signal, wherein the feedback current is injected into the resistive path of the resistance network through which the control current signal flows.

Abstract: A charge pump driver circuit (320) arranged to output a charge pump control signal (325). The charge pump driver circuit (320) includes a bias current source component (330) arranged to generate a bias current (335), a control stage (340) and an output stage (350). The control stage (340) is coupled to the bias current source component (330) and arranged to receive the bias current (335). The control stage (340) is further arranged to receive an input signal (215) and to generate a control current signal (345) proportional to the bias current (335) in accordance with the input signal (215). The output stage (350) is arranged to receive the control current signal (345) generated by the control stage (340) and to generate the charge pump control voltage signal (325) based on the control current signal (345) generated by the control stage (340). The bias current source component (330) is arranged to vary the bias current (335) in response to variations in temperature.