An example radar device includes an antenna system, a transmitter having an input, and an output coupled to an input of the antenna system, the transmitter having modulation circuitry to provide frequency modulated continuous wave (FMCW) signals for transmission by the antenna system; a receive signal processing chain; and a digital front-end. The receive signal processing chain includes an input coupled to an output of the antenna system, and is configured to receive radar reflection signals, process the radar reflected signals to generate an intermediate frequency (IF) baseband signal, and digitize the IF baseband signal to generate digital samples of the IF baseband signal. The digital front-end has an input to receive the digital samples of the IF baseband signal and to phase-shift the digital samples in response to a calibration signal.

The present invention relates to a security surveillance microwave sensor having a reduced false report rate by means of biological signal detection, which monitors and determines a malfunction state or a false alarm generated by environmental factors by detecting humans, animals or objects approaching within a predetermined distance using a microwave signal. The present invention may extend the monitoring distance of security surveillance, set an IF frequency band disturbed by a human body, amplify the IF frequency or use a change in the voltage level to extend the monitoring distance, manage a monitoring state by double-checking transmission and reception of security signals, and reduce the false report rate by distinguishing the false alarms or the malfunction state of the sensor.

The present disclosure relates to adjusting a suppression signal for suppressing a radio frequency (RF) interference signal in a received signal. A method includes generating an RF signal having a first frequency offset from an interference frequency; generating the suppression signal having a second frequency offset from the interference frequency; coupling the suppression signal into the received signal in order to generate a receiver input signal; mixing the receiver input signal with the RF signal in order to generate a mixer output signal; adjusting an amplitude of the suppression signal in order to align amplitudes of different components of the mixer output signal; coupling an adjusted suppression signal, having the interference frequency and the adjusted amplitude, into the received signal; and varying a phase of the adjusted suppression signal in order to reduce a frequency component of the mixer output signal that has the first frequency offset.

In an embodiment, an electronic device may include a first frequency synthesizing circuit outputting a second electronic signal from a first electronic signal, a second frequency synthesizing circuit outputting a fourth electronic signal for converting a frequency of a third electronic signal obtained from the first electronic signal based on the second electronic signal, and a communication processor. The communication processor may be configured to transmit, to the first frequency synthesizing circuit, a first parameter indicating a frequency of the second electronic signal, and changing based on a first preset frequency interval according to a first preset period. The communication processor may be configured to transmit, to the second frequency synthesizing circuit, a second parameter indicating a frequency of the fourth electronic signal based on a frequency of a second clock signal, and changing based on a second preset frequency interval different from the first preset frequency interval.

A method for calibrating a cascaded radar system includes transmitting first radar transmission signal from a radar device. First radar reflection signals corresponding to the respective first radar transmission signal reflected from calibration target are received at each of the radar devices. The first radar reflection signals are demodulated to generate first baseband signals at each of the radar devices. A second radar transmission signal is modulated with respect to the first radar transmission signal at the respective one of the radar devices. The second radar transmission signal is transmitted from the respective one of the radar devices and are received as second radar reflection signals at each of the radar devices. The second radar reflection signals are demodulated to generate second baseband signals at each of the radar devices, and each of the radar devices are calibrated based on the first and second baseband signals.

In an embodiment, a method for testing a millimeter-wave radar module includes: providing power to the millimeter-wave radar module; performing a plurality of tests indicative of a performance level of the millimeter-wave radar module; comparing respective results from the plurality of tests with corresponding test limits; and generating a flag when a result from a test of the plurality of test is outside the corresponding test limits, where performing the plurality of tests includes: transmitting a signal with a transmitting antenna coupled to a millimeter-wave radar sensor, modulating the transmitted signal with a test signal, and capturing first data from a first receiving antenna using an analog-to-digital converter of the millimeter-wave radar sensor, where generating the flag includes generating the flag based on the captured first data.

An integrated circuit for a radar device comprises at least one transmitter and at least one receiver. The integrated circuit comprises: a direct digital synthesizer, DDS, configured to output a control signal; and a multiplier configured to receive a local oscillator input signal and a further input signal from the DDS. In a first mode of operation, the DDS and multiplier cooperate to generate at least one transmitter signal to be transmitted from the radar device; and in a second mode of operation the DDS and multiplier cooperate to generate at least one low frequency modulated transmitter signal to be internally routed to the at least one receiver for calibrating the at least one receiver.

In a radar system, a cancellation circuit is described for compensating for the effects of spillover between each transmitter and a receiver. The cancellation circuit is configured for applying cancellation signals to the receiver which are generated in a cancellation filter utilizing a primary impulse response characteristic corresponding to the spillover, a signal to be transmitted from each transmitter in the radar system, and a range profile output from the receiver. The cancellation circuit may also include a secondary impulse response characteristic module and a dithering module to improve the sensitivity of the receiver.

Level measuring device which can compensate the distortions, caused by an STC filter, of the received signal, by measuring a reference signal which passes through the receiving branch and also through the STC filter, during the ongoing operation of the level measuring device or during manufacture. For example, after passing through the receiving branch, this reference signal can be fed to a microprocessor which can calculate the correction values of the IF signal therefrom. A switch can be provided which can switch over between the reference signal and the IF signal.

An electronic device may include radar circuitry. Control circuitry may calibrate the radar circuitry using a multi-tone calibration signal. A first mixer may upconvert the calibration signal for transmission by a transmit antenna. A de-chirp mixer may mix the calibration signal output by the first mixer with the calibration signal as received by a receive antenna or loopback path to produce a baseband multi-tone calibration signal. The baseband signal will be offset from DC by the frequency gap. This may prevent DC noise or other system effects from interfering with the calibration signal. The control circuitry may sweep the first mixer over the radio frequencies of operation of the radar circuitry to estimate the power droop and phase shift of the radar circuitry based on baseband calibration signal. Distortion circuitry may distort transmit signals used in spatial ranging operations to invert the estimated power droop and phase shift.