This document describes techniques and systems directed at slow-time modulation for multiple radar channels. A set of transmit channels are modulated using code sequences to phase-modulate transmission signals. A second set of transmit channels are modulated using the same codes for phase modulation as well as using a frequency phase shift. Demodulation is achieved by multiplying received signals by the code sequences. Fast Fourier transforms (FFT) are applied to the received signals to generate a range-Doppler map for each receive channel. A non-coherent integration is performed on the range-Doppler maps to form a range-Doppler average map. The range-Doppler average map is shifted by the frequency phase shift, and the minimal of the range-Doppler average map and the shifted range-Doppler average map is retained. These techniques may reduce the impact of signal residue and increase angular resolution by enabling multiple transmit channels to be utilized.

An object detection device includes: a transmission unit transmitting a first transmission wave; a reception unit receiving a first reception wave reflected by an object; a signal processing unit sampling a first processing target signal according to the first reception wave and acquiring a difference signal based on a difference between the first processing target signal for at least one sample at a certain detection timing, and the first processing target signal for a plurality of samples in at least one of first and second periods; a threshold setting unit setting a threshold as a comparison target with the value of the difference signal, based on variation in the values of the first processing target signal for the plurality of samples; and a detection unit detecting information about the object at the detection timing based on a comparison result between the value of the difference signal and the threshold.

The invention relates to a method for operating a pulsed radar system, wherein the pulsed radar system comprises a transmitting antenna, configured to transmit transmission signals, a receiving antenna, configured to receive reflected signals and a signal generating means, configured to generate transmission signals. The method comprises the steps of generating a first transmission signal at a first centre frequency, generating a second transmission signal at a second centre frequency and transmitting the first and the second transmission signals during a predefined transmission time window. The first transmission signal is significantly longer than the second transmission signal. The transmission of the second transmission signal starts during or at the end of the transmission of the first transmission signal and ends essentially at the end of the transmission time window. When the first and/or second transmission signal hits a target a first reflected signal and/or a second reflected signal is generated, wherein the centre frequency of the first reflected signal correlate to the centre frequency of the first transmission signal and the centre frequency of the second reflected signal correlate to the centre frequency of the second transmission signal, and wherein the method further comprises the method step of receiving the first and/or second reflected signal.

A receive path arrangement of a radar sensor of FMCW type comprising a first and second receive path configured to receive reflected radar signals for detection and ranging of objects in a space around the radar sensor; the first receive path configured to provide reflected radar signals between a first and second beat frequency to a first analogue to digital converter for subsequent digital signal processing and wherein; the second receive path includes a second-receive-path filter configured to provide filtered signals by attenuation of the reflected radar signals having frequencies below an intermediate beat frequency, the intermediate beat frequency between the first and second beat frequencies, the second receive path further including a second-receive-path amplifier arrangement configured to provide amplified signals by amplification of the filtered signals and provide the amplified signals to a second analogue to digital converter for subsequent digital signal processing.

A method for determining the range of an object includes transmitting successive radar chirps, adding a frequency offset to the successive radar chirps, the frequency offset being a fraction of a range frequency bin, receiving return signals, constructing frequency transforms from each of the return signals, adding each of the frequency transforms together to create a composite frequency transform, and interpolating the range of the object from a frequency peak detected in the composite frequency transform.

A transmission radar (1) divides each of multiple frequency bands in such a manner that differences between center frequencies in respective frequency bands after the division are equal, and transmits, in time division manner, transmission signals of which transmission frequencies are the center frequencies in respective frequency bands after the division; a rearrangement processing unit (13) rearranges each of the reception video signals converted by the reception radar (5) in such a manner that sets of reception video signals corresponding to the multiple frequency bands before being divided by the transmission radar (1) are arranged in a row; and a band synthesis processing unit (14) performs a band synthesis on each of the reception video signals rearranged by the rearrangement processing unit (13).

Space-time-frequency multiplexing (STFM) schemes for radio frequency (RF) scanning are disclosed in which complementary pairs of sequences (or Golay pairs) are transmitted at different times using multiple frequencies. The transmission and reception of the sequences can occur over multiple transmit (Tx) and/or receive (Rx) radio sectors to scan an entire area for range, azimuth, elevation, and (optionally) velocity of objects therein.

Transmission radars (1-n.sub.TX) (n.sub.TX=1, 2, . . . , N.sub.TX) generate mutually different modulation codes Code(n.sub.TX, h) by cyclically shifting the same code sequence by mutually different cyclic shift amounts (n.sub.TX), and generate mutually different transmission RF signals (4-n.sub.TX) using the mutually different modulation codes Code(n.sub.TX, h). As a result, the number of transmission radars 1-n.sub.TX can be made larger, and target detection accuracy can be made higher than in a case where orthogonal codes are used as mutually different modulation codes.

This document describes techniques and systems directed at slow-time modulation for multiple radar channels. A set of transmit channels are modulated using code sequences to phase-modulate transmission signals. A second set of transmit channels are modulated using the same codes for phase modulation as well as using a frequency phase shift. Demodulation is achieved by multiplying received signals by the code sequences. Fast Fourier transforms (FFT) are applied to the received signals to generate a range-Doppler map for each receive channel. A non-coherent integration is performed on the range-Doppler maps to form a range-Doppler average map. The range-Doppler average map is shifted by the frequency phase shift, and the minimal of the range-Doppler average map and the shifted range-Doppler average map is retained. These techniques may reduce the impact of signal residue and increase angular resolution by enabling multiple transmit channels to be utilized.

A LIDAR apparatus includes a laser source generating a beam of laser light and an imaging device generating an image signal of a pattern of points overlaid upon an image of one or more objects. A controller includes an object detection module receiving the image signal and determining if the object is a protected object, such as a person susceptible to vision impairment from exposure to laser light. A laser intensity module provides an intensity control signal to the laser source and causes the laser source to vary the intensity of the laser light directed toward each of the protected objects. A spatial light modulator may modulate the first beam to project the pattern of points. An SUM control module varies the intensity of the laser light by providing the SIN with an intensity control signal describing one or more low intensity regions corresponding to each of the protected objects,