Abstract: LiDAR optical paths, particularly in co-located emitter/receiver path configurations, can introduce unintended and unwanted reflections due to mirrors, lenses, and/or enclosure materials or glass that can fall on one or more photosensors. These un-desirable signals can cause significant disruptions in output amplifier biasing and/or severe channel saturation. Autonomous vehicle LiDAR is particularly challenging as packaging requirements require complex optics to direct the laser source; the target size, shape, and relative velocity, and distance to the autonomous vehicle are unknown; and the location of the target objects within range are potentially rapidly changing over time. The presently disclosed dual photodiode LiDAR systems are used to separate and compensate for errors introduced by LiDAR optics to improve the accuracy and reliability of LiDAR systems, including but not limited to autonomous vehicle LiDAR systems.

Abstract: The disclosure herein describes reduction of undesired signals within reflected signals of a light detection and ranging (LiDAR) system. For example, a current injection circuit can inject an interference reduction current into an optical detector. Further, for example, an adjustable detection threshold may be adjusted during an undesired signal time period. Still further, for example, a switch can be used to disconnect various detection circuitry to avoid or mask undesired signals.

Abstract: Interference mitigation for a LiDAR system includes identifying a presence or absence of interference from a non-co-located light source in a sample of incident light received by a detector in the LiDAR system. In the absence of interference, a nominal set of reference values is used for one or more spacio-temporal scanning profile trajectory parameters. Scanner components of the LiDAR system are controlled using the nominal set of reference values. In the presence of interference, the nominal set of reference values is augmented to modify the spacio-temporal scanning profile trajectory parameters. Scanner components of the LiDAR system are controlled using the augmented set of reference values to avoid detection of and interference by the non-co-located light source.

Abstract: An optical receiver includes a parasitic current compensation circuit having a reference diode, a sense avalanche photodiode (APD), at least one DC voltage source, and a measurement node. The at least one DC voltage source is configured to generate a first DC bias voltage that varies over time and drives the reference diode, and generates a second DC bias voltage that varies over time and drives the sense APD. A reference parasitic current travels through the reference diode based on the first DC bias voltage. A sense current travels through the sense APD based on the second DC bias voltage and exposure of the sense APD to a light signal. The measurement node receives a sense photocurrent, which is generated by the sense APD in response to the exposure of the sense APD to the light signal, the sense photocurrent including the sense current less the reference parasitic current.

Abstract: An optical engine for a LiDAR system comprises an analog detection channel comprising an avalanche photodiode (APD) optically coupled to light receiving optics and bias circuitry coupled to the APD and configured to adjust a bias set point (BSP) of the APD. Sensors sense disparate environmental factors that impact optical engine performance. Memory stores pre-established APD BSP data including a nominal APD BSP and pre-established dependence data characterizing the impact of disparate environmental factors on the nominal APD BSP. A controller generates, using sensor signals, in-field dependence data characterizing the impact the disparate environmental factors currently have on the nominal APD BSP, calculate an updated APD BSP using the in-field and pre-established dependence data, and shift the BSP of the APD from the nominal APD BSP to the updated APD BSP to enhance optical engine performance.

Abstract: LiDAR optical paths, particularly in co-located emitter/receiver path configurations, can introduce unintended and unwanted reflections due to mirrors, lenses, and/or enclosure materials or glass that can fall on one or more photosensors. These un-desirable signals can cause significant disruptions in output amplifier biasing and/or severe channel saturation. Autonomous vehicle LiDAR is particularly challenging as packaging requirements require complex optics to direct the laser source; the target size, shape, and relative velocity, and distance to the autonomous vehicle are unknown; and the location of the target objects within range are potentially rapidly changing over time. The presently disclosed dual photodiode LiDAR systems are used to separate and compensate for errors introduced by LiDAR optics to improve the accuracy and reliability of LiDAR systems, including but not limited to autonomous vehicle LiDAR systems.