A light detection and ranging (lidar) receiver may include a first photodiode, a first amplifier connected to the first photodiode, and a first analog-to-digital converter (ADC) connected to an output of the first amplifier. The lidar receiver may include a second photodiode, a second amplifier connected to the second photodiode, and a second ADC connected to the second amplifier. The lidar may include a processor connected to an output of the first ADC and an output of the second ADC and a direct-current-to-direct-current converter connected to an output of the processor and to the first photodiode and the second photodiode. The processor may determine, based on the output of the first ADC and the output of the second ADC, a first bias to apply to the first photodiode and a second bias to apply to the second photodiode.

A computer unit for a LiDAR device, which has a laser source configured to emit a laser signal into a transmit path, and a LiDAR sensor arranged in a receive path and configured to detect a laser signal reflected into the receive path. The computer unit is configured to process a multiplicity of laser signal data points of the reflected laser signal. The computer unit is configured to filter halation out of the laser signal data points of the reflected laser signal.

A computer unit for a LiDAR device, which has a laser source configured to emit a laser signal into a transmit path, and a LiDAR sensor arranged in a receive path and configured to detect a laser signal reflected into the receive path. The computer unit is configured to process a multiplicity of laser signal data points of the reflected laser signal. The computer unit is configured to filter halation out of the laser signal data points of the reflected laser signal.

A light detection and ranging (LIDAR) system to transmit optical beams including at least up-chirp frequency and at least one down-chirp frequency toward targets in a field of view of the LIDAR system and receive returned signals of the up-chirp and the down-chirp as reflected from the targets. The LIDAR system may determine multiple frequency peaks associated with the target based on the returned signals. Upon determining that at least one of the multiple frequency peaks is within one or more sets of frequency ranges, the LIDAR system may combine an in-phase signal and a quadrature signal of the returned signals to generate a complex signal that enables determining whether the at least one of the multiple frequency peaks is associated with ghosting. Upon determining to be free from ghosting, the LIDAR system determines one or more of the target location, a target velocity, and a target reflectivity.

The present invention relates to an FMCW-LiDAR distance measurement apparatus in which a light source, in particular a laser, generates a frequency modulated transmission light beam as a transmission signal having a predetermined frequency deviation and transmits said frequency modulated transmission light beam into a measurement zone; a light receiver receives light reflected by objects in the measurement zone as a reception signal; a mixer mixes at least a portion of the transmission signal with the reception signal and with an oscillator frequency to generate a mixed signal; and the oscillator frequency is adapted to a desired measurement zone to achieve a high measurement accuracy in the desired measurement zone.

A silicon phased array based LiDAR device that measures a distance using a quasi-frequency modulation is disclosed. A LiDAR device according to an exemplary embodiment of the inventive concept includes a light source that generates an optical signal, an optical modulator that generates a first optical signal having a quasi-frequency whose a modulation frequency constantly varies with time by modulating a light intensity of the optical signal, an optical splitter that splits optical power of the first optical signal into a reference optical signal and a transmit (Tx) optical signal, an optical transmitter that receives and emits the Tx optical signal toward an object, an optical receiver that receives a receive (Rx) optical signal reflected from the object and transfers the Rx optical signal, an optical coupler that mixes the reference optical signal and the Rx optical signal, a balanced photodetector that detects an intermediate frequency from the optical signal transferred from the optical coupler and a distance calculator that obtains distance information by measuring the intermediate frequency.

A silicon phased array based LiDAR device that measures a distance using a quasi-frequency modulation is disclosed. A LiDAR device according to an exemplary embodiment of the inventive concept includes a light source that generates an optical signal, an optical modulator that generates a first optical signal having a quasi-frequency whose a modulation frequency constantly varies with time by modulating a light intensity of the optical signal, an optical splitter that splits optical power of the first optical signal into a reference optical signal and a transmit (Tx) optical signal, an optical transmitter that receives and emits the Tx optical signal toward an object, an optical receiver that receives a receive (Rx) optical signal reflected from the object and transfers the Rx optical signal, an optical coupler that mixes the reference optical signal and the Rx optical signal, a balanced photodetector that detects an intermediate frequency from the optical signal transferred from the optical coupler and a distance calculator that obtains distance information by measuring the intermediate frequency.

A ranging system includes: a source generating a wideband incident wave that is transmitted toward a target and that is reflected by the target to form a reflected wave; a feedback detector to detect the reflected wave to generate a detected signal; an operator configured to perform low-pass filtering on the detected signal at an adjustable filtering bandwidth to generate a filtered signal, and calculate cross-correlation of a feedback signal that originates from the filtered signal and a reference signal that corresponds to the incident wave to generate a cross-correlation result; and a controller calculating a distance to the target based on an operation output that originates from the cross-correlation result.

A ranging system includes: a source generating a wideband incident wave that is transmitted toward a target and that is reflected by the target to form a reflected wave; a feedback detector to detect the reflected wave to generate a detected signal; an operator configured to perform low-pass filtering on the detected signal at an adjustable filtering bandwidth to generate a filtered signal, and calculate cross-correlation of a feedback signal that originates from the filtered signal and a reference signal that corresponds to the incident wave to generate a cross-correlation result; and a controller calculating a distance to the target based on an operation output that originates from the cross-correlation result.

A light detection and ranging (lidar) receiver may include a first photodiode, a first amplifier connected to the first photodiode, and a first analog-to-digital converter (ADC) connected to an output of the first amplifier. The lidar receiver may include a second photodiode, a second amplifier connected to the second photodiode, and a second ADC connected to the second amplifier. The lidar may include a processor connected to an output of the first ADC and an output of the second ADC and a direct-current-to-direct-current converter connected to an output of the processor and to the first photodiode and the second photodiode. The processor may determine, based on the output of the first ADC and the output of the second ADC, a first bias to apply to the first photodiode and a second bias to apply to the second photodiode.