LiDAR Range and Sensitivity Enhancement

A light detection and ranging (LIDAR) sensor system for autonomous vehicles that uses an integrated light source to improve range and performance. The system has two devices: a laser source that generates an optical signal associated with a local oscillator (LO) signal, and an optical amplifier array device that amplifies the optical signal. The amplified signal is transmitted and receives reflected light. This allows longer ranges compared to using just the laser. The LO signal is also received to determine range and velocity. The integrated light source enables higher energy output from the laser and amplifier for better sensing.

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Adaptive lidar system that can dynamically focus the lasers to optimize imaging of objects and scenes. The system uses high-resolution, high-bandwidth digital micromirror arrays to steer the laser beams. This allows arbitrary pointing and focusing rather than fixed scanning. The micromirrors can independently steer each laser to focus on specific areas of interest. The system can switch between focusing modes to adapt to priorities and conditions. This enables more efficient and effective lidar imaging compared to fixed scanning.

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A low-cost, integrated lidar system using a 1550nm laser and a rotating mirror for scanning instead of a galvanometer. The system simplifies the lidar design by eliminating the galvanometer and using a rotating mirror for scanning. It also uses a frequency multiplier to reduce the wavelength of the reflected signal to match the sensitivity of lower-cost silicon detectors. The simplified design allows low-cost, integrated lidar with a longer detection range compared to 905nm lidar.

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Lidar sensor with non-uniform instantaneous field of view to improve target detection and identification distance. The lidar has a receiving system with changing field of view angles per pixel. The maximum field of view is multiple times the minimum. This compresses the field of view where targets are farther while expanding closer fields. It allows larger entrance pupils for distant targets without affecting nearby ones. The non-uniform FoV improves recognition distance compared to uniform FoV lidars.

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Lidar system with dynamic range optimization to enable reliable detection of objects with varying reflectivities at different distances. The lidar system uses a combination of attenuation, lens design, and detector placement to address issues like optical saturation and false detections due to dynamic range. The system includes a lens setup to concentrate the laser beam onto the detector, an attenuator before the detector to adjust transmissivity, and an aperture to block unwanted components. This allows optimizing the detection of weakly reflective objects at distance without saturation or false detections from bright objects close by.

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Lidar system with improved ranging accuracy and range by using multiple exit areas with different modulation frequencies and emission powers. The system has an emission array with multiple areas that can individually control the modulation frequency and power of the laser signal they emit. This allows optimizing the energy density and modulation frequency for each area to match the detection requirements of near and far fields. By having areas with lower frequency and higher energy density for far field detection and higher frequency and lower energy density for near field, it improves both range and accuracy compared to a single modulation frequency.

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Hybrid pulse/coherent lidar system that combines pulse lidar and coherent lidar techniques to improve sensitivity and range compared to traditional pulse lidar. The system uses a pulse lidar setup with a laser and receiver, but adds a separate coherent light source and detector to mix with the returning pulse. This coherent mixing term provides additional signal that can boost sensitivity for distant or low reflectivity targets. By separately controlling the pulse and coherent light levels, the system can optimize performance for different scenarios.

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Solid-state lidar with multiple transmission modules to improve uniformity and reduce errors in distance measurements. The lidar has multiple transmitting modules arranged around a central receiving module. Each transmitting module contains multiple light emitting units, with lasers arranged in a strip shape. This reduces the length of the emitting units compared to a single long strip. The shorter units have more uniform light emission. Multiple modules allow covering a wide field of view with shorter uniform emitting areas. This reduces distance measurement errors compared to long non-uniform emitting areas. The lidar can also have gap-filling lasers on the module edges to cover blind zones. The modules have electrodes to simultaneously drive all lasers.

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Laser radar system, laser transceiver, and autonomous driving equipment with improved light utilization for longer range and better accuracy. The system uses microlenses or optical shaping to concentrate the laser beams onto the small photosensitive areas of each pixel in the receiver array. This prevents wasted light outside the pixels and increases signal intensity and detection sensitivity.

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A lidar system and method with improved range, resolution, and accuracy compared to conventional lidar. The technique involves using a multiple-beam lidar setup with overlapping beams. Instead of waiting for each pulse to return before emitting the next one, multiple beams are emitted simultaneously in a sweep. This allows faster data acquisition with shorter latency. The overlapping beams provide better resolution and accuracy by reducing angular spacing between adjacent points. However, it does have tradeoffs like reduced range due to shorter dwell time at each beam orientation.

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Lidar system with separate transmitters for long and short range measurements to reduce internal crosstalk interference. The lidar has two transmitters, one for long range and one for short range. An optical system reflects the short range transmitter's beam to a different area on the mirror compared to the long range transmitter's beam, preventing internal crosstalk between the two transmissions. This reduces errors in short range measurements caused by crosstalk light from the long range transmitter.

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Lidar system with adaptive illumination and detection configurations to improve angular resolution and performance when the number of emitter elements is limited. The system has a transmitter with adjustable optical path between the emitters and lens, allowing changing the emitter-lens distances. This enables flood illumination with shorter paths or mixed illumination with longer paths. A control module adjusts emitter activation, exposure times, and lens movement based on scene requirements. This dynamically configures the system for optimal performance in different scenarios. The receiver also has adjustable exposure.

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A lidar system that scans in a constant direction without spreading the beam. The system uses a non-mechanical light transmitting module that drives individual light emitting elements to irradiate light in a specific direction. The light is transmitted through optical systems and received by a corresponding number of photodetector cells. This allows focused beam scanning without mechanical movement. The system combines optical signals from adjacent cells to increase sensitivity. The light emitting elements and photodetectors are arranged in arrays. The light is modulated at different frequencies by one array and demodulated at the same frequencies by the other array.

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Target detection in FMCW LIDAR systems using noise calibration and compensation to improve accuracy and reliability. The method involves estimating the LIDAR system noise in a calibration state and comparing it to the baseband signal in target detection. The comparison determines the likelihood of a signal peak indicating a target. Calibration includes measuring noise with no targets, low power startup, occluded view, and target absent. The calibration provides noise energy, moments, and impulse noise tracking. Masking frequencies below/above thresholds reduces reflections/aliasing.

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Optimizing the resolution, dynamic range, and signal-to-noise ratio of a lidar system by selectively limiting the illumination area compared to the detection area. The lidar has multiple lasers with smaller fields of view than the detectors. An adaptive shutter limits the illumination to a smaller transparent area. The ratio of transparent area to laser fields is chosen for desired lidar performance metrics like resolution, dynamic range, and SNR.

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Light detection and ranging (LIDAR) system that improves performance by adaptively determining the number of laser pulses and timing between pulses based on factors like environmental conditions and measurement requirements. This allows optimizing metrics like signal-to-noise ratio and confidence level. The decision on pulse count and timing is made dynamically during operation.

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Coaxial lidar design with improved accuracy and reliability by eliminating interference in the optical path. The coaxial lidar has a unique optical layout that reduces interference between the outgoing and returning light beams. This improves measurement accuracy by preventing interference that can degrade distance measurements. The coaxial lidar design includes features like coherent cancellation, phase shifting, and optical couplers to achieve this.

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Expanding the field of view and reducing optical signal loss in laser radars using a specialized optical system configuration. The laser radar has a transceiver module, fiber coupling module, conjugate system module, scanning module, and beam expansion module. The conjugate system focuses the emitted laser and adjusts the distance between its focal point and the scanning module to expand the scanning field. During reception, the conjugate system brings the focal point closer to the scanning module to reduce offset. This balances expanding view with minimizing offset for better performance.

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Laser radar receiving device, system, stray light elimination method and storage medium that reduces blind spots in short range laser radar. The key idea is to distinguish between stray light signals and actual echoes by controlling the bias voltage applied to the photoelectric conversion unit. Before ranging, the device collects the stray light signal and sets a lower bias voltage. During ranging, it increases the bias voltage to enhance the conversion gain. This allows separating the weaker echoes from the stronger stray signals based on waveform differences.

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A lidar sensor design to improve accuracy and reduce pixel count for lidar sensors with small, closely-spaced pixels. The design addresses issues of parallax, distortion, and light collection efficiency in lidar sensors with small pixels. It involves limiting the observation area to the actual field of view where reflected light is expected, instead of the entire sensor area. This reduces unnecessary collection of ambient light or noise from pixels. The sensor also compensates for lens distortion by adjusting the expected projected shape and position of the light on the focal plane. This improves accuracy by accounting for the non-ideal lens behavior. By limiting the observation area and accounting for distortion, it reduces the number of pixels needed compared to using the full sensor area. This can significantly lower pixel count and cost while still providing high accuracy.

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