Infineon Technologies Ag

Lukas Heschl

Rainer Stuhlberger

Jochen Oliver Schrattenecker

Bernhard Gstoettenbauer

Alexander Onic

Helmut Kollmann

Bernhard Greslehner-Nimmervoll

Mathias Zinnoecker

Evangelos Koutsouradis

A circuit includes an RF oscillator coupled in a phase-locked loop. The phase-locked loop is configured to receive a digital input signal, which is a sequence of digital words, and to generate a feedback signal for the RF oscillator based on the digital input signal. The circuit further includes a digital-to-analog conversion unit that includes a pre-processing stage configured to pre-process the sequence of digital words and a digital-to-analog-converter configured to convert the pre-processed sequence of digital words into the analog output signal. The circuit includes circuitry configured to combine the analog output signal and the feedback signal to generate a control signal for the RF oscillator. The pre-processing stage includes a word-length adaption unit configured to reduce the word-lengths of the digital words and a sigma-delta modulator coupled to the word-length adaption unit downstream thereof and configured to modulate the sequence of digital words having reduced word-lengths.

Generation of fast frequency ramps

One example of a radar device includes a phase-locked loop for generating a radiofrequency signal. The phase-locked loop has a multi-modulus divider. The radar device furthermore comprises a delta-sigma modulator for generating a modulated signal for the multi-modulus divider, and a signal generator for generating an input signal for the delta-sigma modulator. The radar device has monitoring circuits, wherein a first monitoring circuit is configured to monitor a locked state of the phase-locked loop, a second monitoring circuit is configured to monitor the delta-sigma modulator, and a third monitoring circuit is configured to monitor the signal generator.

Radar device, monitoring device, phase control circuit and method for monitoring a signal processing circuit

A radar transmitter is described. The radar transmitter may include the following: a transmit channel which is designed to receive a local oscillator signal and to generate a high-frequency (HF) radar signal based on the local oscillator signal; a phase shifter contained in the transmit channel which is designed to set a phase of the HF radar signal depending on an input phase value; and a coupler contained in the transmit channel which is designed to receive the HF radar signal and output the HF radar signal at an output contact. A phase controller circuit is assigned to the transmit channel, where the circuit is coupled with the coupler and is designed to receive the local oscillator signal and the HF radar signal, and to adjust the input phase value for the phase shifter based on a phase difference between the local oscillator signal and the HF radar signal.

Radar transmitter with output phase control

A method for a radar device is described. According to one example implementation, the method comprises generating an RF signal using a voltage-controlled oscillator (VCO), wherein the frequency of the RF signal depends on a first tuning voltage and a second tuning voltage. The method also comprises setting the second tuning voltage using a phase-locked loop coupled to the VCO, with the result that the frequency of the RF signal corresponds to a desired frequency. The first tuning voltage is changed in such a manner that the second tuning voltage set by the phase-locked loop corresponds approximately to a predefined value. Another example implementation relates to a method for a radar device comprising: generating an RF signal using a VCO, wherein the frequency of the RF signal depends on a tuning voltage, setting the tuning voltage using a phase-locked loop coupled to the VCO, with the result that the frequency of the RF signal corresponds to a desired frequency, and determining a differential VCO gain of the VCO. The bandwidth of the phase-locked loop is set on the basis of the determined VCO gain.

Bandwidth adjustment in a phase-locked loop of a local oscillator

An RF circuit comprises a charge pump configured to generate current pulses having a first current amplitude and a predetermined duration; and a capacitive element configured to receive the current pulses and to generate a tuning voltage depending thereon. An RF oscillator is configured to generate an RF signal having a frequency that is dependent on the tuning voltage. The RF circuit comprises a measuring circuit configured to generate a measurement signal representing the tuning voltage or the frequency of the RF signal. A controller circuit is configured to drive the charge pump in order to change the first amplitude of a current pulse by a current difference, and ascertain a first change in the measurement signal and a second change in the measurement signal. A measurement value for the first amplitude can be calculated based on the first change and the second change based on the current difference.

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Linz, Austria

Lukas Heschl