Combining the many functions of a LIDAR system to assist vehicle operation

Abstract

To provide, in relation to light detection and ranging (LIDAR) in the field of optics, a system and a method for assisting in vehicle operation by combining multiple functions of a LIDAR system.SOLUTION: A light detection and ranging (LIDAR) system includes a semiconductor substrate and one or more optical components disposed on the semiconductor substrate. The one or more optical components are configured to receive a light beam from a laser light source, in which the light beam is associated with a local oscillator (LO) signal, split the light beam into a first split light beam and a second split light beam, transmit the first split light beam and the second split light beam to an optical device, receive from the optical device a first reflected beam associated with the first split light beam and a second reflected beam associated with the second split light beam, pair the first reflected beam with the LO signal, and pair the second reflected beam with the LO signal.SELECTED DRAWING: Figure 1a

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATION(S) This application claims priority to patent application Ser. No. 16 / 915,404, filed June 29, 2020, now U.S. Patent No. 10,948,600, the disclosures of which are incorporated herein by reference. [Background technology]

[0002] Laser-based optical ranging, commonly referred to as LIDAR, a mnemonic for light detection and ranging, and sometimes called RADAR, is used in a variety of applications, from altimetry to photography to collision avoidance. LIDAR offers finer-scale ranging resolution with a smaller beam size than traditional microwave ranging systems such as RADAR (radio-wave detection and ranging). Optical ranging is achieved using different techniques, including direct ranging, which is based on the round-trip travel time of a light pulse to an object; chirp detection, which is based on the frequency difference between a transmitted chirped light signal and the return signal scattered from the object; and phase-coded detection, which is based on a single-frequency phase-change sequence that can be distinguished from a delayed signal. Summary of the Invention [Means for solving the problem]

[0003] Aspects of the present disclosure relate generally to the field of optics, light detection and ranging (LIDAR), and more particularly to systems and methods that combine multiple functions of a LIDAR system to assist in vehicle operation.

[0004] Embodiments disclosed herein relate to LIDAR systems. The LIDAR system includes one or more optical components configured to receive a light beam generated by a laser light source, the light beam associated with a local oscillator (LO) signal. In some embodiments, the one or more optical components are configured to split the light beam into a first split light beam and a second split light beam. In some embodiments, the one or more optical components are configured to transmit the first split light beam and the second split light beam to an optical device. In some embodiments, the one or more optical components are configured to receive from the optical device a first reflected beam associated with the first split light beam and a second reflected beam associated with the second split light beam. In some embodiments, the one or more optical components are configured to pair the first reflected beam with the LO signal and pair the second reflected beam with the LO signal.

[0005] In another aspect, the present disclosure relates to a method for combining multiple functions of a LIDAR system. In some embodiments, the method includes receiving a light beam generated by a laser light source, the light beam associated with an LO signal. In some embodiments, the method includes splitting the light beam into a first split light beam and a second split light beam. In some embodiments, the method includes transmitting the first split light beam and the second split light beam to an optical device. In some embodiments, the method includes receiving from the optical device a first reflected beam associated with the first split light beam and a second reflected beam associated with the second split light beam. In some embodiments, the method includes pairing the first reflected beam with an LO signal and pairing the second reflected beam with the LO signal.

[0006] In another aspect, the present disclosure relates to a LIDAR system including a semiconductor substrate and one or more optical components disposed on the semiconductor substrate. The one or more optical components are configured to receive an optical beam generated by a laser light source, where the optical beam is associated with an LO signal. The one or more optical components are configured to split the optical beam into a first split optical beam and a second split optical beam. The one or more optical components are configured to transmit the first split optical beam and the second split optical beam to an optical device. The one or more optical components are configured to receive from the optical device a first reflected beam associated with the first split optical beam and a second reflected beam associated with the second split optical beam. The one or more optical components are configured to pair the first reflected beam with an LO signal and pair the second reflected beam with the LO signal.

[0007] In some implementations, the one or more optical components are configured to receive a second optical beam generated by the laser light source or the second laser light source, where the second optical beam is associated with the LO signal. The one or more optical components are configured to split the third split optical beam into a second split optical beam and a fourth split optical beam. The one or more optical components are configured to transmit the third split optical beam and the fourth split optical beam to the optical device. The one or more optical components are configured to receive from the optical device a third reflected beam associated with the third split optical beam and a fourth reflected beam associated with the fourth split optical beam. The one or more optical components are configured to pair the third reflected beam with a second LO signal and pair the fourth reflected beam with the second LO signal.

[0008] In some implementations, the one or more optical components are configured to receive an LO signal and split the LO signal into a first split LO signal and a second split LO signal, and the one or more optical components are configured to receive the LO signal from an LO input, where the LO signal at the LO input is less than 5 milliwatts.

[0009] In some embodiments, the LIDAR system includes a first photodetector and a second photodetector. One or more optical components provide a first split LO signal and a first reflected beam to the first photodetector, causing the first photodetector to generate a first electrical signal from the first split LO signal and the first reflected beam. The one or more optical components provide a second split LO signal and a second reflected beam to the second photodetector, causing the second photodetector to generate a second electrical signal from the second split LO signal and the second reflected beam. Signal crosstalk associated with the first electrical signal and the second electrical signal is less than -55 dB within 1 MHz and 200 MHz.

[0010] In some embodiments, the first photodetector includes a pair of photodiodes, each of which has a common mode rejection ratio (CMRR) of 30 dB or greater. The first photodetector has a bandwidth of 3 dB between 80 kHz and 650 MHz. The first photodetector has a responsivity of 0.9 A / W or greater. The light beam has an operating wavelength that is the same as or substantially the same as 1550 nanometers.

[0011] In some implementations, the LIDAR system is 5x10 -12 The LIDAR system includes a transimpedance amplifier (TIA) having a peak noise-equivalent power (NEP) of less than Watts per square root Hertz. The first photodetector is configured to provide a first electrical signal to the TIA. In some implementations, the LIDAR system includes a TIA having a gain between 4 kilo-ohms and 25 kilo-ohms. The first photodetector is configured to provide the first electrical signal to the TIA.

[0012] In some embodiments, the LIDAR system includes a semiconductor substrate. The semiconductor substrate includes one or more optical components. The semiconductor substrate includes a plurality of outputs, each associated with a pitch between 31.75 micrometers and 381 micrometers. In some embodiments, the optical beam has an operating wavelength between 1400 nanometers and 1600 nanometers.

[0013] In some embodiments, the LIDAR system includes a modulator configured to modulate the optical beam before one or more optical components receive the optical beam. The modulator has a modulation bandwidth between 600 MHz and 1000 MHz. In some embodiments, signal crosstalk associated with the first reflected beam and the first split optical beam is 55 dB or less within 1 MHz and 200 MHz. In some embodiments, internal scattering of the first split optical beam into the first reflected beam is -66 dB or less compared to the Tx transmit power. The scattering is associated with maintained polarization. In some embodiments, internal scattering of the first split optical beam into the first reflected beam is -84 dB or less compared to the Tx transmit power. In some embodiments, the scattering is associated with flipped polarization. In some embodiments, the first split optical beam has a duty cycle of 33% or less.

[0014] In another aspect, the present disclosure relates to a method for combining multiple functions of a LIDAR system. The method includes one or more optical components disposed on a semiconductor substrate receiving an optical beam generated by a laser light source, where the optical beam is associated with an LO signal. The method includes the one or more optical components splitting the optical beam into a first split optical beam and a second split optical beam. The method includes the one or more optical components transmitting the first split optical beam and the second split optical beam to an optical device. The method includes the one or more optical components receiving from the optical device a first reflected beam associated with the first split optical beam and a second reflected beam associated with the second split optical beam. The method includes the one or more optical components pairing the first reflected beam with an LO signal and pairing the second reflected beam with the LO signal.

[0015] In another aspect, the present disclosure relates to an autonomous vehicle control system. The autonomous vehicle control system includes a semiconductor substrate, one or more LIDAR circuits disposed on the semiconductor substrate, and one or more processors. The one or more LIDAR circuits are configured to receive a light beam generated by a laser light source. The light beam is associated with an LO signal. The one or more LIDAR circuits are configured to split the light beam into a first split light beam and a second split light beam. The one or more LIDAR circuits are configured to transmit the first split light beam and the second split light beam to an optical device. The one or more LIDAR circuits are configured to receive from the optical device a first reflected beam associated with the first split light beam and a second reflected beam associated with the second split light beam. The one or more LIDAR circuits are configured to pair the first reflected beam with the LO signal to generate a first paired signal and pair the second reflected beam with the LO signal to generate a second paired signal. The one or more processors are configured to control operation of the autonomous vehicle using the first paired signal and the second paired signal.

[0016] In another aspect, the present disclosure relates to a LIDAR system. The LIDAR system includes a laser light source configured to output optical signals and a transceiver. The transceiver includes a plurality of transmit (TX) outputs and a plurality of receive (RX) inputs, through which optical signals are output into an environment and through which light beams are received from objects in the environment. The transceiver is configured to receive one or more LO signals, transmit one or more optical signals received from the laser light source into the environment via the plurality of TX outputs, receive first light reflected and returned from one or more objects in the environment via the plurality of RX inputs, and output a first LO signal and a first reflected light of the one or more LO signals. The plurality of TX outputs and the plurality of RX inputs are located on a first side of the transceiver.

[0017] In some embodiments, the multiple TX outputs and multiple RX inputs are interleaved on a first side of the transceiver. In some embodiments, the LIDAR system includes a detector from which a first return light and a first LO signal are output. In some embodiments, the transceiver includes a first semiconductor substrate including multiple TX outputs and a second semiconductor substrate including multiple RX inputs. In some embodiments, the first semiconductor substrate and the second semiconductor substrate are arranged at an interval that corresponds to the pitch of the multiple TX outputs or the pitch of the multiple RX inputs.

[0018] In some embodiments, the transceiver includes one or more LO inputs, one or more TX inputs, and a plurality of first outputs, where one or more LO signals are provided to the transceiver via the one or more LO inputs, one or more optical signals are output to the transceiver via the one or more TX inputs, and a first return light and a first LO signal are provided to the plurality of first outputs. The one or more LO outputs, the one or more TX inputs, and the plurality of first outputs are located on a second side of the transceiver. The transceiver further includes a plurality of second RX outputs. The transceiver is configured to receive second return light reflected from one or more objects in the environment via the plurality of RX inputs and provide a second LO signal among the second return light and the one or more LO signals to the plurality of second RX outputs. The one or more LO inputs, the one or more TX inputs, the plurality of first outputs, and the plurality of second RX outputs are located on the second side of the transceiver. The one or more LO inputs and the one or more TX inputs are located between (1) the plurality of first RX outputs and (2) the plurality of second RX outputs. In some implementations, the LIDAR system further includes a scanner configured to receive one or more optical signals transmitted from the multiple TX outputs via free space.

[0019] In another aspect, the present disclosure relates to an autonomous vehicle control system including a LIDAR system and one or more processors. The LIDAR system includes a laser light source configured to output optical signals and a transceiver. The transceiver includes a plurality of transmit (TX) outputs and a plurality of receive (RX) inputs, through which optical signals are output into an environment via the plurality of transmit outputs and through which light beams are received from objects in the environment via the plurality of receive inputs. The transceiver is configured to receive one or more LO signals, transmit one or more optical signals received from the laser light source into the environment via the plurality of TX outputs, receive first light reflected and returned from one or more objects in the environment via the plurality of RX inputs, and output a first LO signal and a first reflected light of the one or more LO signals. The plurality of TX outputs and the plurality of RX inputs are located on a first side of the transceiver. The one or more processors are configured to control operation of the autonomous vehicle using the first returned light and the first LO signal.

[0020] In some embodiments, the multiple TX outputs and multiple RX inputs are interleaved on a first side of the transceiver. In some embodiments, the transceiver includes a first semiconductor substrate including the multiple TX outputs and a second semiconductor substrate including the multiple RX inputs. In some embodiments, the first semiconductor substrate and the second semiconductor substrate are arranged at an interval corresponding to the pitch of the multiple TX outputs or the pitch of the multiple RX inputs.

[0021] In some embodiments, the transceiver includes one or more LO inputs, one or more TX inputs, and a plurality of first outputs, where one or more LO signals are provided to the transceiver via the one or more LO inputs, one or more optical signals are output to the transceiver via the one or more TX inputs, and the first return light and the first LO signal are provided to the plurality of first outputs. The one or more LO outputs, the one or more TX inputs, and the plurality of first outputs are located on a second side of the transceiver. The transceiver further includes a plurality of second RX outputs. The transceiver is configured to receive second return light reflected from one or more objects in the environment via the plurality of RX inputs, and to provide a second LO signal among the second return light and the one or more LO signals to the plurality of second RX outputs. The one or more LO inputs, the one or more TX inputs, the plurality of first outputs, and the plurality of second RX outputs are located on the second side of the transceiver.

[0022] In another aspect, the present disclosure relates to an autonomous vehicle. The autonomous vehicle includes at least one of a steering system or a braking system, a LIDAR system, and at least one processor. The LIDAR system includes a laser light source configured to output optical signals and a transceiver. The transceiver includes a plurality of transmit (TX) outputs and a plurality of receive (RX) inputs, where the optical signals are output to an environment via the plurality of transmit outputs and the optical beams are received from objects in the environment via the plurality of receive inputs. The transceiver is configured to receive one or more LO signals, transmit one or more optical signals received from the laser light source to the environment via the plurality of TX outputs, receive first light reflected and returned from one or more objects in the environment via the plurality of RX inputs, and output a first LO signal and a first reflected light of the one or more LO signals. The plurality of TX outputs and the plurality of RX inputs are located on a first side of the transceiver. The one or more processors are configured to control operation of at least one of the steering system or the braking system using the first returned light and the first LO signal.

[0023] Other aspects, features, and advantages will be readily apparent from the following detailed description, which sets forth a number of specific embodiments, including the best mode contemplated before carrying out the invention. It should be noted that other embodiments may also have different features and advantages, and that many details may be modified in various obvious aspects without departing from the spirit and scope of the invention. Accordingly, the drawings and descriptions are illustrative in nature and should not be considered limiting. [Brief explanation of the drawings]

[0024] The embodiments are illustrated by way of example, not limitation, and in the accompanying drawings, like reference numerals refer to like elements. [Figure 1a] 1 is a block diagram illustrating an example system environment for an autonomous vehicle according to some implementations. [Figure 1b] FIG. 1 is a block diagram illustrating an example system environment for commercial autonomous trucks according to some implementations. [Figure 1c] FIG. 1 is a block diagram illustrating an example system environment for commercial autonomous trucks according to some implementations. [Figure 1d] FIG. 1 is a block diagram illustrating an example system environment for commercial autonomous trucks according to some implementations. [Figure 2] 1 is a block diagram illustrating an example environment of a LIDAR system for an autonomous vehicle according to some implementations. [Figure 3] FIG. 1 is a block diagram illustrating an example coherent LIDAR transceiver for operation in a vehicle according to some implementations. [Figure 4] FIG. 1 is a block diagram illustrating an exemplary two semiconductor substrate coherent LIDAR transceiver according to some implementations. [Figure 5] 1 is a flowchart illustrating an exemplary method for combining multiple functions of a LIDAR system according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0025] A LIDAR system includes a transmit (Tx) path and a receive (Rx) path. The transmit (Tx) path includes a laser source that provides an optical signal (sometimes referred to as a "beam") derived from (or related to) an LO signal, one or more modulators that modulate the phase and / or frequency of the optical signal using continuous wave (CW) modulation or quasi-CW modulation, and an amplifier that amplifies the modulated signal before transmitting the signal to an optic (e.g., an oscillating scanner, a unidirectional scanner, a Risley prism, a circulator optic, and / or a beam collimator).

[0026] The optical instrument is configured to steer the amplified light received from the Tx path toward an object in an environment within a given field of view, receive a return signal reflected from the object, and provide the return signal to a receive (Rx) path.

[0027] The receive (Rx) path includes a mixer (e.g., 50 / 50) that mixes the LO signal with the return signal to produce a down-converted signal, and a TIA amplifier that amplifies the down-converted signal. The Rx path provides the down-converted (now amplified) signal to an autonomous vehicle control system to determine the distance to an object and / or measure the object's velocity.

[0028] In conventional LIDAR systems, a fiber coupling (sometimes called a "fiber cable") connects the Tx path, Rx path, and optics together. The fiber coupling provides flexibility during testing and development of LIDAR systems by allowing different channels to be used with different Tx / Rx apertures and optical circulation methods.

[0029] However, the bulkiness of fiber coupling limits the ability of LIDAR designers to add additional channels—each requiring more fiber couplings—and / or reduce the size of the LIDAR system to the size required for efficient automotive applications.

[0030] Thus, the present disclosure relates to systems and methods that combine multiple functions of a LIDAR system (e.g., splitting, collecting, combining, redirecting, pairing, etc.) to assist in vehicle operation.

[0031] As described below, the Tx path of a multi-channel coherent LIDAR transceiver generally receives a light beam from a laser source (via the Tx input). The laser source generates a light beam based on an LO signal. The Tx path of the coherent LIDAR transceiver splits (e.g., multiplies, replicates, regenerates, etc.) the light beam into multiple light paths and emits the light beam into free space (via the Tx output) toward one or more objects. The Rx path of the multi-channel coherent LIDAR transceiver receives (via the Rx input) return light reflected from one or more objects into Rx waveguides. Each Rx waveguide is paired with a respective Tx output of the Tx path. The Rx path splits the LO signal into multiple LO signals, which are then combined with the light returned from the Rx waveguides using splitters (e.g., 50 / 50). The Rx path provides the combined signal to one or more detectors (via the Rx output).

[0032] Various exemplary implementations described herein include one or more of the following features: (1) the Tx and LO inputs of the coherent LIDAR transceiver are each split into two inputs, which improves matching with the LIDAR engine architecture; (2) the Tx / Rx outputs to free space occur along one edge of the coherent LIDAR transceiver where the waveguides are interleaved with the Tx / Rx outputs (e.g., Tx-Rx-Tx-Rx), where the pitch is determined by free space circulation requirements and / or beam collimation optics. (3) The LO and Tx inputs are paired (e.g., LO_A, LO_B; Tx_A, Tx_B, etc.) to function as independent subsystems; (4) the input power levels to the Tx inputs are high (e.g., >1 watt each); (5) the fiber coupling to the coherent LIDAR transceiver input receives high power; (6) the scattering of the Tx path (sometimes referred to as "directional") into the Rx path (e.g., toward the detector) is very small during interleaving; (7) reflections from the output facet are minimized (e.g., the angled glare of the coherent LIDAR transceiver). (8) When the output beam quality is defined as the output of the waveguide, the output mode of the coherent LIDAR transceiver should also have high quality (e.g., low distortion from the transverse electromagnetic (TEMOO) beam); (9) The functions of the LIDAR system (e.g., splitting, collecting, combining, redirecting, pairing, etc.) are combined into a single integrated photonic device; (10) The coherent LIDAR transceiver is implemented using a programmable logic controller (PLC).

[0033] In the foregoing description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present invention. However, it will be apparent to those skilled in the art that the present disclosure may be practiced without such specific details. In other instances, well-known structures and devices are shown in block diagram form to avoid unnecessarily obscuring the present disclosure.

[0034] 1. System environment for autonomous vehicles FIG. 1a is a block diagram illustrating an example system environment for an autonomous vehicle according to some implementations.

[0035] 1a, an exemplary autonomous vehicle 100 may embody various techniques disclosed herein. For example, vehicle 100 may include a prime mover 104 powered by an energy source 106, a powertrain 102 powering a drivetrain 108, a controller system 110 including a direction control 112, a powertrain controller 114, and a brake controller 116. While vehicle 100 may be embodied in a variety of forms, including vehicles that transport people and / or cargo and operate in a variety of environments, it should be understood that the components 102-116 described above may vary widely based on the type of vehicle in which the components are used.

[0036] For simplicity, the embodiments discussed below focus on wheeled land vehicles, such as cars, vans, trucks, buses, etc. In such embodiments, prime mover 104 includes (among other things) one or more electric motors and / or internal combustion engines. Energy sources include, for example, a fuel system (providing, e.g., gasoline, diesel, hydrogen, etc.), a battery system, solar panels, or other renewable energy sources, and / or a fuel cell system. Drivetrain 108 includes wheels and / or tires operating in conjunction with a transmission and / or any other mechanical drive components that convert the power output of prime mover 104 into vehicle motion, as well as one or more brakes configured to controllably stop or slow vehicle 100 and appropriate directional or steering components to control the trajectory of vehicle 100 (e.g., a rack and pinion steering linkage that rotates one or more wheels of vehicle 100 about a generally vertical axis to change the wheel's rotational plane angle relative to the vehicle's longitudinal axis). In some implementations, a combination of powertrains and energy sources is used (e.g., in the case of electric / gas hybrid vehicles), and in some instances multiple electric motors (e.g., dedicated to individual wheels or axles) are used as prime movers.

[0037] The direction controller 112 includes one or more actuators and / or sensors that control and receive feedback from the direction or steering components to steer the vehicle 100 along a desired trajectory. The power controller 114 is configured to control the output of the powertrain 102, for example, by controlling the output power of the prime mover 104 to control the gears of the transmission in the drivetrain 108, thereby controlling the speed and / or direction of the vehicle 100. The brake controller 116 is configured to control one or more brakes, for example, disc or drum brakes coupled to the wheels of the vehicle, to slow or stop the vehicle.

[0038] Other vehicle types, including but not limited to off-road vehicles, all-terrain or tracked vehicles, construction equipment, etc., inevitably use different powertrains, drivetrains, energy sources, directional controllers, powertrain controllers, and brake controllers. Also, in some implementations, some of the components are combined, for example, where vehicle rearward control is primarily handled by varying the output of one or more prime movers. Thus, the implementations described herein are not limited to the specific application of the techniques described herein in autonomous wheeled land vehicles.

[0039] Various levels of autonomous driving control for vehicle 100 are embodied in vehicle controller system 120, which includes one or more processors 122 and one or more memories 124, each configured to execute program code instructions 126 stored in memory 124. The processor(s) may include, for example, graphic processing unit(s) (“GPU(s)”) and / or central processing unit(s) (“CPU(s)”).

[0040] The sensors 130 include various sensors adapted to gather information from the vehicle's environment for use in controlling the vehicle's operation. For example, the sensors 130 include a radar sensor 134, a LIDAR sensor 136, and a 3D positioning sensor 138, such as an accelerometer, a gyroscope, a magnetometer, or one of a number of satellite navigation systems, such as GPS, GLONASS (Global Navigation Satellite System, or Global Navigation Satellite System), BDS (BeiDou Navigation Satellite System), Galileo, or Compass. The 3D positioning sensor 138 is used to determine the vehicle's position on Earth using satellite signals. The sensors 130 include a camera 140 and / or an inertial measurement unit (IMU) 142. The camera 140 may be a monographic or stereographic camera and may record still and / or video images. The IMU 142 includes multiple gyroscopes and accelerometers that detect linear and rotational motion of the vehicle 100 in three directions. One or more encoders (not shown), such as wheel encoders, are used to monitor the rotation of one or more wheels of the vehicle 100. Each sensor 130 outputs sensor data at a different data rate than the data rates of the other sensors 130.

[0041] The outputs of the sensors 130 are provided to a set of control subsystems 150, including a localization subsystem 152, a planning subsystem 156, a perception subsystem 154, and a control subsystem 158. The localization subsystem 152 functions to accurately determine the position and orientation (sometimes referred to as "pose") of the vehicle 100 within the surrounding environment and approximately within some reference frame. The autonomous vehicle's position is part of a labeled autonomous vehicle data generation and is compared to the positions of additional vehicles within the same environment. The perception subsystem 154 functions to detect, track, determine, and / or identify objects within the vehicle's 100 environment. Machine learning models, depending on the implementation, are used to track the objects. The planning subsystem 156 functions to plan a trajectory for the vehicle 100 for some time frame given a desired destination, as well as stationary or moving objects within the environment. Machine learning models, depending on the implementation, are used to plan the tracking of the objects. The controller subsystem 158 functions to generate appropriate controller signals to control various controllers in the controller system 120 to implement the planned trajectory of the vehicle 100. A machine learning model is used to generate one or more signals to control the autonomous vehicle to implement the planned trajectory.

[0042] It should be understood that the collection of components depicted in FIG. 1a for vehicle control system 120 is merely exemplary in nature. Individual sensors may be omitted in some implementations. Additionally or alternatively, in some implementations, the various types of sensors depicted in FIG. 1 are overlapped and / or used to cover different areas around the vehicle, although other types of sensors may be used. Similarly, different types and / or combinations of control subsystems may be used in other implementations. Also, while subsystems 152-158 are shown as being separate from processor 122 and memory 124, it should be understood that in some implementations, some or all of the functionality of subsystems 152-158 is embodied in program code instructions 126 resident in one or more memories 124 and executed by one or more processors 122, and that in some examples, subsystems 152-158 are implemented using the same processor(s) and / or memory. The subsystems may be implemented, at least in part, using various dedicated circuit logic, various processors, various field programmable gate arrays (FPGAs), various application-specific integrated circuits (ASICs), various real-time controllers, etc., and as described above, many subsystems may use circuits, processors, sensors, and / or other components. Additionally, the various components within vehicle control system 120 may be networked in various ways.

[0043] In some embodiments, vehicle 100 also includes a secondary vehicle control system (not shown) used as a redundant or backup control system for vehicle 100. In some embodiments, the secondary vehicle control system operates the entire autonomous vehicle 100 in the event of an adverse event in vehicle controller system 120, while in other embodiments, the secondary vehicle control system may only have limited functionality, such as performing a controlled stop of vehicle 100 in response to an adverse event detected in primary vehicle control system 120. In other embodiments, the secondary vehicle control system is omitted.

[0044] Numerous different architectures, including various combinations of software, hardware, circuit logic, sensors, networks, etc., may be used to implement the various components shown in FIG. 1a. Each processor may be embodied, for example, by a microprocessor, and each memory may be embodied, for example, by a random access memory (RAM) device, including main storage as well as supplementary memory such as cache memory, non-volatile or backup memory (e.g., programmable or flash memory), and read-only memory (ROM). Each memory may also be considered to be virtual memory, including memory storage physically located elsewhere within vehicle 100, such as any cache memory within the processor, as well as storage capacity used, for example, as stored in a mass storage device or other computer or controller. One or more of the processors shown in FIG. 1a, or entirely separate processors, may be used to implement additional functions within vehicle 100 beyond the purpose of autonomous control, such as the operation of entertainment systems, doors, lights, convenience features, etc.

[0045] Additionally, for additional storage, vehicle 100 may include one or more mass storage devices, such as, among others, removable disk drives, hard disk drives, "DASD" (direct access storage devices), optical drives (e.g., CD drives, DVD drives, etc.), "SSD" (solid state storage drives), network-attached storage, storage area networks, and / or tape drives.

[0046] Vehicle 100 also includes a user interface 164 that allows vehicle 100 to receive various inputs from a user or operator and generate outputs for the user or operator, such as one or more displays, touchscreens, voice and / or gesture interfaces, buttons, and other tactile controls, etc. Alternatively, user inputs may be received via an app on another computer or electronic device, such as a portable device, or via a web interface.

[0047] Vehicle 100 also includes one or more network interfaces, e.g., network interface 162, adapted to communicate with one or more networks 170 (e.g., a "Local Area Network" (LAN), a "Wide Area Network" (WAN), a wireless network, and / or the Internet, among others), allowing communication of information with other computers and electronic devices, including, for example, a central service such as a cloud service from which vehicle 100 receives environmental and other data for use in autonomous control. Data collected by one or more sensors 130 is uploaded via network 170 to computing system 172 for further processing. In some implementations, a timestamp is added to each instance of vehicle data before uploading.

[0048] 1a, as well as various additional controllers and subsystems described herein, generally operate under an operating system as described in detail below, and execute or rely on various computer software applications, components, programs, objects, modules, data structures, etc. It should be noted that various applications, components, programs, objects, and modules may also execute on one or more processors in other computers coupled to vehicle 100 via network 170, for example, in a distributed, cloud-based, or client-server computing environment, whereby the processing required to implement the functionality of a computer program is allocated across multiple computers and / or services via the network.

[0049] In general, the routines executed to implement the various embodiments described herein are referred to herein as "program code," whether embodied in an operating system or a specific application, component, program, object, module, or instruction sequence, or any subset thereof. Program code may reside at various times in various memory and storage devices of a computer, and when read or executed by one or more processors, comprises one or more instructions that perform the steps necessary to perform the steps or elements that implement various aspects of the present disclosure. Additionally, embodiments are described in the context of fully functional computers and systems, as described below, and it should be understood that the various embodiments described herein may be distributed in various forms as a program product, and that an embodiment is embodied regardless of the particular type of computer-readable medium actually used to achieve this distribution.

[0050] Examples of computer-readable media include, among others, tangible and non-transitory media such as volatile and non-volatile memory devices, floppy disks and other removable disks, solid state drives (SSDs), hard disk drives, magnetic tape, and optical disks (e.g., CD-ROMs, DVDs, etc.).

[0051] Furthermore, various program code described below will be identified based on the application in which it is implemented in a particular embodiment. However, any specific program names described below are merely for convenience, and the present disclosure should not be limited to any specific application identified and / or suggested by such names. Furthermore, it should be understood that the present disclosure is not limited to the specific organization and allocation of program functions described herein, given the myriad ways in which computer programs can be organized into routines, procedures, methods, modules, objects, etc., as well as the various ways in which program functions can be allocated to the various software layers (e.g., operating systems, libraries, APIs, applications, applets, etc.) present in a typical computer.

[0052] The environment illustrated in Figure 1a is not intended to limit the implementations disclosed herein, and indeed, other alternative hardware and / or software environments may be used without departing from the scope of the implementations disclosed herein.

[0053] 2. FM LIDAR for autonomous driving applications The truck includes a LIDAR system (e.g., vehicle control system 120 of FIG. 1a, LIDAR system 201 of FIG. 2, etc.). In some implementations, the LIDAR system encodes an optical signal using frequency modulation and scatters the encoded optical signal into free space using optics. By detecting the frequency difference between the encoded optical signal and the return signal reflected by an object, a frequency modulated (FM) LIDAR system determines the object's position and / or precisely measures the object's velocity using the Doppler effect. In some implementations, the FM LIDAR system uses continuous wave (referred to as FMCW LIDAR) or quasi-continuous wave (referred to as FMQW LIDAR). In some implementations, the LIDAR system encodes an optical signal using phase modulation (PM) and scatters the encoded optical signal into free space using optics.

[0054] FM or phase-modulated (PM) LIDAR systems offer substantial advantages over conventional LIDAR systems for autonomous driving and / or commercial truck applications. In some examples, an object (e.g., a pedestrian wearing dark clothing) has low reflectivity, resulting in a small amount (e.g., 10% or less) of light striking the object being reflected back to the FM or PM LIDAR system's sensor (e.g., sensor 130 of FIG. 1a). In other examples, an object (e.g., a road sign) has a large amount (e.g., greater than 10%) of light striking the object being reflected back to the FM or PM LIDAR system's sensor.

[0055] Regardless of the object's reflectivity, FM LIDAR systems can detect (e.g., classify, recognize, locate, etc.) objects at greater distances (e.g., 2x) than traditional LIDAR systems. For example, an FM LIDAR system can detect a low-reflectivity object 300 meters away and a high-reflectivity object 400 meters away.

[0056] To achieve this improvement in detection capabilities, FM LIDAR systems use sensors (e.g., sensor 130 in FIG. 1a). In some implementations, such sensors are sensitive to single photons, meaning they are capable of detecting the smallest amounts of light. FM LIDAR systems use infrared wavelengths (e.g., 950 nm, 1550 nm, etc.) in some applications, but are not limited to infrared wavelength ranges (e.g., near-infrared: 800 nm-1500 nm; mid-infrared: 1500 nm-5600 nm; and far-infrared: 5600 nm-1,000,000 nm). Operating an FM or PM LIDAR system at infrared wavelengths allows the FM or PM LIDAR system to broadcast stronger light pulses or beams while still meeting eye safety standards. Conventional LIDAR systems are sometimes not sensitive to single photons and / or operate only at near-infrared wavelengths, requiring limited light output (and distance detection capabilities) for eye safety reasons.

[0057] Thus, by detecting objects at greater distances, FM LIDAR systems have more time to react to unexpected obstacles. Indeed, even a few extra milliseconds can improve safety and stability, especially for large vehicles (e.g., commercial trucks) operating at highway speeds.

[0058] Another advantage of FM LIDAR systems is that they provide accurate instantaneous velocity for each data point. In some implementations, velocity measurement is achieved using the Doppler effect, which shifts the frequency of light received from an object based on at least one of the radial velocity (e.g., the direction vector between the detected object and the sensor) or the frequency of the laser signal. For example, for on-road speeds of less than 100 m / s, at a wavelength of 1550 nanometers (nm), this corresponds to a frequency shift of less than 130 MHz. This frequency shift is so small that it is difficult to detect directly in the optical domain. However, by using coherent detection in FMCW, PMCW, or FMQW LIDAR systems, the signal is converted to the RF domain, where the frequency shift can be calculated using various signal processing techniques. This allows autonomous vehicle control systems to process incoming data more quickly.

[0059] Calculating instantaneous velocity also makes it easier for the FM LIDAR system to determine rare data points as distances or objects and / or track how those points move over time. For example, if an FM LIDAR sensor (e.g., sensor 130 in FIG. 1a) receives only a few returns (e.g., hits) from an object 300 m away, but the returns provide velocity values ​​of interest (e.g., moving toward the vehicle at a speed >70 mph), the FM LIDAR system and / or the autonomous vehicle control system can weight each of them relative to their probability of being associated with the object.

[0060] Faster identification and / or tracking of an FM LIDAR system provides the autonomous vehicle control system with more time to activate the vehicle. Better knowledge of how fast an object is moving also allows the autonomous vehicle control system to better plan a response.

[0061] Another advantage of FM LIDAR systems is that they are less static than traditional LIDAR systems. That is, traditional LIDAR systems, which are designed to be more sensitive to light, typically perform poorly in bright sunlight. Such systems also tend to be susceptible to crosstalk (e.g., when sensors are confused by each other's light pulses or light beams) and self-interference (e.g., when a sensor is confused by its own previous light pulse or light beam). To overcome these shortcomings, vehicles using traditional LIDAR systems typically require extra hardware, complex software, and / or more computational power to manage such "noise." In contrast, FM LIDAR systems do not experience these issues because each sensor is designed to respond only to its own light characteristics (e.g., light beam, light wave, light pulse). If the returning light does not match the timing, frequency, and / or wavelength of the originally transmitted light, the FM sensor filters (e.g., removes, ignores, etc.) that data point. Such FM LIDAR systems produce (e.g., generate, derive) more accurate data with less hardware or software, enabling safer, smoother driving.

[0062] Finally, FM LIDAR systems are easier to scale than traditional LIDAR systems. As more autonomous vehicles (e.g., automobiles, commercial trucks, etc.) appear on the roads, vehicles equipped with FM LIDAR systems do not have to contend with interference issues due to sensor crosstalk. Also, FM LIDAR systems use less optical peak power than traditional LIDAR sensors. Some or all of the optical components for such FM LIDARs can be fabricated on a single chip, creating inherent advantages as discussed herein.

[0063] 2.1 Commercial trucks 1b is a block diagram illustrating an example system environment for a commercial autonomous truck, according to some embodiments. The environment 100B includes a commercial truck 102B for transporting cargo 106B. In some embodiments, the commercial truck 102B includes a vehicle configured for long-haul freight transport, local freight transport, intermodal freight transport (i.e., transportation in which a road-based vehicle is used as one of multiple modes of transportation to move cargo), and / or some other road-based freight transport application. In some embodiments, the commercial truck 102B is a flatbed truck, a refrigerated truck (e.g., a reefer truck), a ventilated van (e.g., a dry van), a moving truck, etc. In some embodiments, the cargo 106B is goods and / or products. In some embodiments, the commercial truck 102B includes a trailer for transporting the cargo 106B, such as a flatbed trailer, a lowboy trailer, a step deck trailer, an extendable flatbed trailer, a sidekit trailer, etc.

[0064] The environment 100B includes an object 110B (illustrated as another vehicle in FIG. 1b) within a distance range of 30 meters or less from the truck.

[0065] The commercial truck 102B includes a LIDAR system 104B (e.g., the FM LIDAR system of FIG. 1a, the vehicle control system 120, the LIDAR system 201 of FIG. 2, etc.) for determining the distance to the object 110B and / or measuring the speed of the object 110B. Although FIG. 1b shows one LIDAR system 104B mounted on the front of the commercial truck 102B, the number of LIDAR systems on the commercial truck and the mounting areas of the LIDAR systems are not limited to any particular number or area. The commercial truck 102B may include any number of LIDAR systems 104B (or components such as sensors, modulators, coherent signal generators, etc.) mounted on any area of ​​the commercial truck 102B (e.g., the front, rear, sides, top, bottom, underside, and / or bottom) to facilitate detection of objects in any free space for the commercial truck 102B.

[0066] As shown, LIDAR system 104B in environment 100B is configured to detect objects (e.g., other vehicles, bicycles, trees, street signs, potholes, etc.) within a short distance (e.g., 30 meters or less) from commercial truck 102B.

[0067] 1c is a block diagram illustrating an example system environment for a commercial autonomous truck according to some implementations. Environment 100C includes the same components included in environment 100B (e.g., commercial truck 102B, cargo 106B, LIDAR system 104B, etc.).

[0068] Environment 100C includes objects 110C (illustrated as other vehicles in FIG. 1c) at distances (i) greater than 30 meters and (ii) less than or equal to 150 meters from the commercial truck. As shown, in environment 100C, LIDAR system 104B is configured to detect objects (e.g., other vehicles, bicycles, trees, street signs, depressions, etc.) at a distance (e.g., 100 meters) from commercial truck 102B.

[0069] 1d is a block diagram illustrating an example system environment for a commercial autonomous truck according to some implementations. Environment 100D includes the same components included in environment 100B (e.g., commercial truck 102B, cargo 106B, LIDAR system 104B, etc.).

[0070] Environment 100D includes objects 100D (illustrated as other vehicles in FIG. 1d) that are within a distance range of greater than 150 meters from commercial truck 102B. As shown, in environment 100D, LIDAR system 104B is configured to detect objects (e.g., other vehicles, bicycles, trees, street signs, depressions, etc.) that are within a distance (e.g., 300 meters) from commercial truck 102B.

[0071] In commercial truck applications, it is important to effectively detect objects at all ranges due to the increased weight and therefore longer stopping distances required for such vehicles. FM LIDAR systems (e.g., FMCW and / or FMQW systems) or PM LIDAR systems are highly suitable for commercial truck applications due to the advantages described above. As a result, commercial trucks equipped with such systems have improved capabilities for safely transporting people and goods over short or long distances, thereby improving the safety of not only the commercial truck but also surrounding vehicles. In various implementations, such FM or PM LIDAR systems are used in semi-autonomous driving applications, in which a driver is present on the commercial truck and some functions of the commercial truck operate autonomously using the FM or PM LIDAR system, or in fully autonomous driving applications, in which the commercial truck operates entirely using the FM or PM LIDAR system alone or in combination with other vehicle systems.

[0072] 3. Continuous wave modulation and quasi-continuous wave modulation In LIDAR systems that use CW modulation, the modulator continuously modulates the laser light. For example, if the modulation cycle is 10 seconds, the input signal is modulated for the full 10 seconds. Alternatively, in LIDAR systems that use quasi-continuous wave modulation, the modulator modulates the laser light to have active and inactive portions. For example, for 10 cycles, the modulator only modulates the laser light for 8 seconds (sometimes referred to as the "active portion"), but does not modulate the laser light for 2 seconds (sometimes referred to as the "inactive portion"). In this way, the LIDAR system can reduce power consumption during the 2 seconds because the modulator does not need to provide a continuous signal.

[0073] In FMCW LIDAR for autonomous driving applications, it is advantageous to operate the LIDAR system using quasi-CW modulation where FMCW measurement and signal processing methods are used, but the optical signal is not always on (e.g., enabled, powered on, transmitting, etc.). In some implementations, the quasi-CW modulation has a duty cycle of 1% or more and up to 50%. If energy is required during the actual measurement time in the off (disabled, powered down, etc.) state, there may be a boost to the signal-to-noise ratio (SNR) and / or a reduction in signal processing requirements to coherently integrate all the energy over a longer time domain.

[0074] 4. Coherent LIDAR Transceiver with Multiple Channels 2 is a block diagram illustrating an example environment for a LIDAR system for an autonomous vehicle according to some implementations. The environment 200 includes a LIDAR system 201 including a transmit (Tx) path and a receive (Rx) path. The Tx path includes one or more Tx input / output ports (not shown) and one or more Rx input / output ports (not shown).

[0075] In some embodiments, the semiconductor substrates and / or semiconductor packages include Tx and Rx paths. In some embodiments, a first semiconductor substrate and / or first semiconductor package includes Tx paths and a second semiconductor substrate and / or second semiconductor package includes Rx paths. In some arrangements, the Rx input / output ports and / or Tx input / output ports occur along one or more edges of one or more semiconductor substrates and / or semiconductor packages.

[0076] The environment 200 includes one or more optical instruments 210 (e.g., an oscillating scanner, a unidirectional scanner, a Risley prism, a circulator optic, and / or a beam collimator, etc.) coupled to the LIDAR system 201. In some implementations, the one or more optical instruments 210 are coupled to the Tx path via one or more Tx input / output ports. In some implementations, the one or more optical instruments 210 are coupled to the Rx path via one or more Rx input / output ports.

[0077] The environment 200 includes a vehicle control system (e.g., vehicle control system 120 of FIG. 1) coupled to a LIDAR system. In some implementations, the vehicle control system 120 is coupled to the Rx path via one or more Rx input / output ports.

[0078] The Tx path includes laser source 202, modulator 204A, modulator 204B, and amplifier 206. The Rx path includes mixer 208, detector 212, and TIA 212. While Figure 2 shows a selected number of components and only one input / output channel, environment 200 may include any number of components and / or input / output channels coupled together in any arrangement (any combination) to facilitate combining multiple functions of the LIDAR system to support vehicle operation.

[0079] The laser source 202 is configured to generate an optical signal derived from (or related to) the LO signal. In some implementations, the optical beam has an operating wavelength equal to or substantially equal to 1550 nanometers. In some implementations, the optical beam has an operating wavelength between 1400 nanometers and 1600 nanometers.

[0080] Laser source 202 is configured to provide an optical signal to modulator 204A, which is configured to modulate the phase and / or frequency of the optical signal based on a first radio frequency (RF) signal (depicted as "RF1" in FIG. 2) using CW modulation or quasi-CW modulation to generate a modulated optical signal. Modulator 204A is configured to transmit the modulated optical signal to amplifier 206. Amplifier 206 is configured to amplify the modulated optical signal to generate an amplified optical signal to optical device 210.

[0081] The optics are configured to steer the amplified light received from the Tx path toward an object 218 in an environment within a given field of view, receive a return signal reflected from the object, and provide the return signal to a mixer 208 in the receive (Rx) path.

[0082] The laser source 202 is configured to provide the LO signal to the modulator 204B, which modulates the phase and / or frequency of the LO signal using CW modulation or quasi-CW modulation based on a second RF signal (shown as "RF2" in FIG. 2) to generate a modulated LO signal, and transmits the modulated LO signal to the mixer 208 in the Rx path.

[0083] The mixer 208 mixes (e.g., combines, multiplies, etc.) the modulated LO signal with the return signal to generate a down-converted signal and transmits the down-converted signal to the detector 212. In some arrangements, the mixer 208 is configured to transmit the modulated LO signal to the detector 212.

[0084] The detector 212 generates an electrical signal based on the down-converted signal and transmits the electrical signal to the TIA 214. In some arrangements, the detector 212 is configured to generate an electrical signal based on the down-converted signal and the modulated signal.

[0085] The TIA 214 is configured to amplify the electrical signal and transmit the amplified electrical signal to the vehicle control system 120 .

[0086] In some implementations, the TIA 214 is rated at 5 picowatts per square root hertz (i.e., 5 x 10 per square root hertz). -12 In some implementations, the TIA 214 has a gain between 4 kilo-ohms and 25 kilo-ohms.

[0087] In some implementations, detector 212 and / or TIA 214 have a 3 dB bandwidth between 80 kHz and 650 MHz.

[0088] Vehicle control system 210 is configured to determine the distance to object 218 and / or measure the velocity of object 218 based on one or more electrical signals received from the TIA.

[0089] In some implementations, modulator 204A and / or modulator 204B have a bandwidth between 600 MHz and 1000 MHz.

[0090] 3 is a block diagram illustrating an exemplary coherent LIDAR transceiver for operation in a vehicle according to some implementations. Environment 300 includes coherent LIDAR transceiver 301 and detectors 303, 304, 305, 306, 307, 308, 309, and 310 (collectively referred to as "detectors 303-310"). A laser source (e.g., laser source 202 in FIG. 2) generates an LO signal via a Tx path (e.g., Tx path in FIG. 2) and provides the LO signal (modulated or unmodulated) to LO input 360 (illustrated as "LOA-A" in FIG. 3). In some implementations, the LO signal at LO input 360 is less than 5 milliwatts.

[0091] Coherent LIDAR transceiver 301 splits the LO signal received from LO input 306 into LO signal 360-1 and LO signal 306-2. Coherent LIDAR transceiver 301 splits LO signal 360-1 into LO signal 360-1a and LO signal 306-1b. Coherent LIDAR transceiver 301 splits LO signal 360-2 into LO signal 360-2a and LO signal 306-2b.

[0092] The laser source provides an LO signal (modulated or unmodulated) to LO input 366 (depicted as "LOA-B" in FIG. 3). Coherent LIDAR transceiver 301 splits the LO signal received from LO input 366 into LO signal 366-1 and LO signal 366-2. Coherent LIDAR transceiver 301 splits LO signal 366-1 into LO signal 366-1a and LO signal 366-1b. Coherent LIDAR transceiver 301 splits LO signal 266-2 into LO signal 366-2a and LO signal 366-2b.

[0093] The laser source generates an LO signal via a Tx path (e.g., the Tx path in FIG. 2) and provides an optical signal (modulated or unmodulated) to a Tx input 362 (illustrated as "Tx-A" in FIG. 3). The coherent LIDAR transceiver 301 splits the optical signal received from the Tx input 362 into optical signals 362-1 and 362-2. The coherent LIDAR transceiver 301 splits optical signal 362-1 into optical signals 362-1a and 362-1b. The coherent LIDAR transceiver 301 splits optical signal 362-2 into optical signals 362-2a and 362-2b.

[0094] The laser source provides an optical signal (modulated or unmodulated) to Tx input 364 (illustrated as "Tx-B" in FIG. 3). Coherent LIDAR transceiver 301 splits the optical signal received from Tx input 364 into optical signal 364-1 and optical signal 364-2. Coherent LIDAR transceiver 301 splits optical signal 364-1 into optical signal 364-1a and optical signal 364-1b. Coherent LIDAR transceiver 301 splits optical signal 364-2 into optical signal 364-2a and optical signal 364-2b.

[0095] The coherent LIDAR transceiver 301 emits an optical signal 362-1a into free space toward one or more objects via the Tx output 320, receives return light reflected from the objects via the Rx input 322, and provides the return light and LO signal 360-2b to the detector 303 (illustrated as "RX-1" in FIG. 3 ). The detector 303 generates an electrical signal based on the return light and / or the LO signal 360-2b.

[0096] The coherent LIDAR transceiver 301 emits an optical signal 362-1b into free space toward one or more objects via the Tx output 324, receives return light reflected from the objects via the Rx input 326, and provides the return light and LO signal 360-2a to the detector 304 (illustrated as "Rx-2" in FIG. 3 ). The detector 304 generates an electrical signal based on the return light and / or the LO signal 360-2a.

[0097] The coherent LIDAR transceiver 301 emits an optical signal 362-2a into free space via the Tx output 328 towards one or more objects, receives return light reflected from the objects via the Rx input 330, and provides the return light and LO signal 360-1b to the detector 305 (illustrated as "Rx-1" in FIG. 3 ). The detector 305 generates an electrical signal based on the return light and / or the LO signal 360-1b.

[0098] The coherent LIDAR transceiver 301 emits an optical signal 362-2b into free space toward one or more objects via the Tx output 332, receives return light reflected from the objects via the Rx input 334, and provides the return light and LO signal 360-1a to the detector 306 (illustrated as "Rx-2" in FIG. 3). The detector 306 generates an electrical signal based on the return light and / or the LO signal 360-1a.

[0099] The coherent LIDAR transceiver 301 emits an optical signal 364-1a into free space toward one or more objects via the Tx output 336, receives return light reflected from the objects via the Rx input 338, and provides the return light and an LO signal 366-2b to a detector 307 (illustrated as "Rx-1" in FIG. 3 ). The detector 307 generates an electrical signal based on the return light and / or the LO signal 366-2b.

[0100] The coherent LIDAR transceiver 301 emits an optical signal 364-1b into free space toward one or more objects via the Tx output 340, receives return light reflected from the objects via the Rx input 342, and provides the return light and an LO signal 366-2a to a detector 308 (illustrated as "Rx-2" in FIG. 3 ). The detector 308 generates an electrical signal based on the return light and / or the LO signal 366-2a.

[0101] The coherent LIDAR transceiver 301 emits an optical signal 364-2a into free space toward one or more objects via the Tx output 344, receives return light reflected from the objects via the Rx input 346, and provides the return light and an LO signal 366-1b to a detector 309 (illustrated as "Rx-1" in FIG. 3 ). The detector 309 generates an electrical signal based on the return light and / or the LO signal 366-1b.

[0102] The coherent LIDAR transceiver 301 emits an optical signal 364-2b into free space via the Tx output 348 towards one or more objects, receives return light reflected from the objects via the Rx input 350, and provides the return light and LO signal 366-1a to a detector 310 (illustrated as "Rx-2" in FIG. 3 ). The detector 310 generates an electrical signal based on the return light and / or the LO signal 366-1a.

[0103] In some implementations, signal crosstalk associated with return light (sometimes referred to as a "return beam") returned from an internal surface to the LIDAR sensor and emissions of the corresponding optical signals (e.g., optical signals 362-1a, 362-1b, 362-2a, 362-2b, 364-1a, 364-1b, 364-2a, 364-2b, etc.) is less than -55 dB within 1 MHz and 200 MHz in all other channels relative to the channel in which the reflected beam is obtained.

[0104] In some implementations, scattering of the optical signal from the interior surfaces to the corresponding return light reflected back to the LIDAR sensor is less than -66 dB relative to the transmitted Tx power, but the scattering is related to the polarization being maintained.

[0105] In some implementations, the scattering of the optical signal from the interior surface to the corresponding return light reflected back to the LIDAR sensor is less than -84 dB relative to the transmitted Tx power, but the scattering is relative to the polarization rotated by 90 degrees.

[0106] In some implementations, the signal crosstalk between any electrical signals generated by detectors 303-310 is less than -55 dB relative to electrical signals generated on other detectors within the frequency range of 1 MHz and 200 MHz.

[0107] In some implementations, one or more of the detectors 303-301 includes a pair of photodiodes. In some implementations, the pair of photodiodes in a detector has a CMRR of 30 dB or greater.

[0108] In some implementations, any of detectors 303-310 has a 3 dB bandwidth between 80 kHz and 650 MHz.

[0109] In some implementations, one or more of detectors 303-310 have a responsivity of 0.9 A / W or greater.

[0110] In some implementations, any of the optical signals (e.g., optical signals 362-1a, 362-1b, 362-2a, 362-2b, 364-1a, 364-1b, 364-2a, 364-2b, etc.) have a duty cycle of 33% or less.

[0111] 4 is a block diagram illustrating an exemplary coherent LIDAR transceiver on two semiconductor substrates according to some implementations. The environment 400 includes a semiconductor substrate 402 containing an Rx / LO path and a semiconductor substrate 404 containing a Tx path. The semiconductor substrates 402 and 404 are arranged back-to-back with a spacing "A" that approximates the pitch (e.g., the distance between the centers of two inputs / outputs) in a single-chip concept. In some implementations, the inputs / outputs of the semiconductor substrates each have a pitch that is between 31.75 micrometers and 381 micrometers.

[0112] 5 is a flowchart illustrating an exemplary method for combining multiple functions of a LIDAR system, according to an embodiment. While the steps in FIG. 5 are shown as integral steps in a particular order for purposes of illustration, in other embodiments, one or more steps, or portions thereof, may be performed in a different order or overlap in time, directly or in parallel, omitted, one or more additional steps may be added, or the method may be combined or modified in some manner. In some embodiments, some or all of the operations of method 500 are performed by coherent LIDAR transceiver 301 of FIG. 3.

[0113] Method 500 includes step 502 of receiving a light beam generated by a laser light source. In some implementations, the light beam is associated with an LO signal. Method 500 includes step 504 of splitting the light beam into a first split light beam and a second split light beam. Method 500 includes step 506 of transmitting the first split light beam and the second split light beam to an optical device. Method 500 includes step 508 of receiving from the optical device a first reflected beam associated with the first split light beam and a second reflected beam associated with the second split light beam. Method 500 includes step 510 of pairing the first reflected beam with the LO signal and pairing the second reflected beam with the LO signal.

[0114] The above description is provided to enable those skilled in the art to practice various aspects described herein. Various modifications to these aspects will be apparent to those skilled in the art, and the generic principles defined herein apply to other aspects. Accordingly, the claims are not limited to the aspects set forth herein but are intended to accord the full scope consistent with the claims. References to elements herein as "a," "an," or "an" do not mean "one and only one" unless expressly stated otherwise, but rather "one or more." Unless expressly stated otherwise, the term "some" refers to one or more. All structural and functional equivalents of elements of various aspects described through descriptions known or known to those skilled in the art are expressly incorporated herein by reference and are achieved by the claims. Furthermore, nothing disclosed herein shall be designated as common to all, regardless of whether such disclosure is expressly recited in the claims. Any claim element shall be construed as a means-function unless the element is expressly recited as a "means."

[0115] It should be understood that any particular order or hierarchy of blocks in the disclosed processes is an example of a descriptive approach. Based on design preferences, it should be understood that the particular order of steps or hierarchy of blocks in the processes may be rearranged while remaining within the scope of the above description. The accompanying methods claim the present composition of the various blocks in a sample order and are not meant to be limited to the particular order or hierarchy presented.

[0116] The above description of the disclosed embodiments is provided to enable one skilled in the art to make or use the disclosed subject matter. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of the description. Thus, the above description is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0117] The various examples shown and described are provided merely as examples to illustrate various features of the claims. Features shown and described for any given example are not necessarily limited to the associated example, but may be used or combined with other examples shown and described. Furthermore, the claims are not intended to be limited to any single example.

[0118] The above method descriptions and processor flowcharts are provided merely as illustrative examples and do not require or imply that the blocks of the various examples be performed in the order presented. Those skilled in the art will understand that the order of the blocks in the above examples may be performed in any order. Words such as "then," "then," and "next" do not limit the order of the blocks. These words are used merely to guide the reader in describing the method. Additionally, any reference to a claim element in the singular should not be construed as limiting the element to the singular.

[0119] The various illustrative logic blocks, modules, circuits, and algorithm steps described in connection with the disclosure herein may be embodied as electronic hardware, computer software, or a combination thereof. To clearly illustrate this interchangeability of hardware and software, the various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is embodied as hardware or software depends on the particular application and design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

[0120] The various example logic blocks, modules, and circuits described in connection with the disclosure herein may be embodied or performed by a general-purpose processor, a DSP, an ASIC, an FPGA, or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be embodied as a combination of computing devices, such as a DSP and a microprocessor, multiple microprocessors, one or more microprocessors with a DSP core, or any other such configuration. Alternatively, some blocks or methods may be performed by circuitry specified for a given function.

[0121] In some illustrative examples, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented as software, the functions may be stored as one or more instructions or code on a non-transitory computer-readable or processor-readable storage medium. Blocks of methods or algorithms disclosed herein may be embodied in processor-executable software modules resident on a non-transitory computer-readable or processor-readable storage medium. A non-transitory computer-readable or processor-readable storage medium is any storage medium accessible by a computer or processor. By way of example, and not limitation, such non-transitory computer-readable or processor-readable storage media include RAM, ROM, EEPROM, flash memory, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium accessible by a computer that stores desired program code in the form of instructions or data structures. As used herein, disk and disc include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVDs), floppy disks, and Blu-ray discs, where disks typically reproduce data magnetically while discs reproduce data optically using a laser. Combinations of the above are also included within the scope of non-transitory computer-readable and processor-readable media. Additionally, the operations of a method or algorithm may reside as one or any combination or set of code and / or instructions on a non-transitory processor-readable and / or computer-readable storage medium, which may be embodied in a computer program product.

[0122] The above description of the disclosed examples is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these examples will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of the above description. Thus, the above description is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0123] Notwithstanding that the numerical ranges and parameters set forth in the broad scope are approximations, the numerical values ​​set forth in the non-limiting examples are reported as precisely as possible. However, all numerical values ​​inherently contain certain errors resulting from the standard deviations found in the respective test measurements made in preparing this specification. Additionally, unless otherwise clear from the context, numerical values ​​set forth herein have an indicative precision given by the lowest digit. Thus, a value of 1.1 means a value from 1.05 to 1.15. The term "about" is used to indicate a broader range around a given value; unless otherwise clear from the context, it refers to a broader range around the lowest digit, such as "about 1.1" meaning a range of 1.0 to 1.2. If the lowest digit is unclear, the term "about" refers to a factor of two. For example, "approximately X" means a value in the range of 0.5X to 2X. For example, about 100 means a value in the range of 50 to 200. Additionally, all ranges disclosed herein should be understood to include any and all subranges subsumed therein. For example, the range "less than 10" includes any and all sub-ranges between (and including) a minimum value of 0 and a maximum value of 10. That is, any and all sub-ranges having a minimum value greater than or equal to 0 and a maximum value less than or equal to 10 (e.g., 1 to 4) are included.

[0124] Although some embodiments of the present invention have been described in the context of one or more high-resolution Doppler LIDAR systems mounted on certain areas (e.g., front, rear, side, top, and / or bottom) of a personal vehicle, embodiments are not limited to this context. In other embodiments, one or multiple systems of the same type, or other high-resolution LIDARs with or without a Doppler component, with overlapping or non-overlapping fields of view, or one or more such systems mounted on large or small, driverless or autonomous land, sea, or air vehicles are employed. In other embodiments, scanning high-resolution LIDARs are mounted in temporary or permanently fixed locations on land or sea. [Item of invention] [Item 1] 1. A light detection and ranging (LIDAR) system including a semiconductor substrate and one or more optical components attached to the semiconductor substrate, the one or more optical components comprising: receiving a light beam from a laser light source, said light beam being associated with a local oscillator (LO) signal; splitting the light beam into a first split light beam and a second split light beam; transmitting the first split light beam and the second split light beam to an optical device; receiving a first reflected beam associated with the first split light beam and a second reflected beam associated with the second split light beam from the optical device; A LIDAR system configured to pair the first reflected beam with the LO signal and pair the second reflected beam with the LO signal. [Item 2] The one or more optical components include: receiving a second optical beam generated by the laser light source or the second laser light source, the second optical beam being associated with an LO signal; splitting the second light beam into a third split light beam and a fourth split light beam; transmitting the third split light beam and the fourth split light beam to the optical device; receiving a third reflected beam associated with the third split light beam and a fourth reflected beam associated with the fourth split light beam from the optical device; Item 1. The LIDAR system of item 1, further configured to pair the third reflected beam with the second LO signal and pair the fourth reflected beam with the second LO signal. [Item 3] The one or more optical components include: receiving the LO signal; Item 1. The LIDAR system of item 1, further configured to split the LO signal into a first split LO signal and a second split LO signal. [Item 4] Item 4. The LIDAR system of item 3, wherein the one or more optical components receive the LO signal from an LO input, and the LO signal at the LO input is less than 5 watts. [Item 5] a first optical detector; and a second optical detector, The one or more optical components include: providing the first split LO signal and the first reflected beam to the first photodetector, causing the first photodetector to generate a first electrical signal according to the first split LO signal and the first reflected beam; 4. The LIDAR system of claim 3, further configured to provide the second split LO signal and the second reflected beam to the second photodetector, and to cause the second photodetector to generate a second electrical signal according to the second split LO signal and the second reflected beam. [Item 6] Item 6. The LIDAR system of item 5, wherein a signal crosstalk associated with the first electrical signal and the second electrical signal is −55 dB or less within 1 MHz and 200 MHz. [Item 7] 6. The LIDAR system according to item 5, wherein the first photodetector includes a pair of photodiodes, and the pair of photodiodes has a CMRR (common mode rejection ratio) of 30 dB or more. [Item 8] Item 6. The LIDAR system of item 5, wherein the first optical detector has a 3 dB bandwidth between 80 kHz and 650 MHz. [Item 9] Item 6. The LIDAR system of item 5, wherein the first optical detector has a responsivity of 0.9 A / W (amperes per watt) or greater, and the optical beam has an operating wavelength equal to or substantially equal to 1550 nanometers. [Item 10] 6. The LIDAR system of claim 5, further comprising a transimpedance amplifier (TIA) having a peak noise-equivalent power (NEP) of less than 5×10 Watts per square root Hertz, wherein the first photodetector is configured to provide the first electrical signal to the TIA. [Item 11] Item 6. The LIDAR system of item 5, further comprising a TIA having a gain between 4 kilo-ohms and 25 kilo-ohms, wherein the first photodetector is configured to provide the first electrical signal to the TIA. [Item 12] Item 1. The LIDAR system of item 1, wherein a semiconductor substrate includes the one or more optical components, the semiconductor substrate includes a plurality of outputs, each of the plurality of outputs associated with a pitch between 31.75 micrometers and 381 micrometers. [Item 13] Item 1. The LIDAR system of item 1, wherein the light beam has an operating wavelength between 1400 nanometers and 1600 nanometers. [Item 14] In autonomous vehicles, at least one of a steering system or a braking system; a vehicle controller including one or more processors, the one or more processors including: one or more optical components disposed on the semiconductor substrate receiving a light beam generated by the laser light source, said light beam being related to the LO signal; the one or more optical components split the light beam into a first split light beam and a second split light beam; the one or more optical components transmitting the first split light beam and the second split light beam to an optical device; the one or more optical components receiving a first reflected beam associated with the first split optical beam and a second reflected beam associated with the second split optical beam from an optical device; the one or more optical components pairing the first reflected beam with an LO signal and pairing the second reflected beam with an LO signal; An autonomous vehicle that controls at least one of the steering system or the braking system using the first reflected beam paired with the LO signal and the second reflected beam paired with the LO signal. [Item 15] 14. An autonomous vehicle control system including the LIDAR system according to any one of items 1 to 13.

Claims

1. 1. A light detection and ranging (LIDAR) sensor system for a vehicle, comprising: the LIDAR sensor system comprises a transceiver; The transceiver includes: a plurality of inputs configured to receive a plurality of local oscillator (LO) signals and a plurality of optical signals received from a laser source; a plurality of transmit (TX) outputs configured to transmit the plurality of optical signals to an environment of the vehicle via the plurality of TX outputs; a plurality of receive (RX) inputs configured to receive a plurality of first return lights and a plurality of second return lights reflected from one or more objects in the environment; a plurality of first RX outputs configured to receive the plurality of first return lights and a plurality of first LO signals among the plurality of LO signals in correspondence with each other; a plurality of second RX outputs configured to receive the plurality of second return lights and a plurality of second LO signals among the plurality of LO signals in correspondence with each other; 1. A LIDAR sensor system comprising:

2. 2. The LIDAR sensor system of claim 1, wherein the plurality of TX outputs and the plurality of RX inputs are provided on a first side of the transceiver.

3. The plurality of inputs include: a plurality of LO inputs through which the plurality of LO signals are provided to the transceiver; a plurality of TX inputs through which the plurality of optical signals are provided to the transceiver; 3. The LIDAR sensor system of claim 2, comprising:

4. 4. The LIDAR sensor system of claim 3, wherein the plurality of LO inputs, the plurality of TX inputs, and the plurality of first RX outputs are disposed on a second side of the transceiver.

5. 4. The LIDAR sensor system of claim 3, wherein the plurality of LO inputs, the plurality of TX inputs, the plurality of first RX outputs, and the plurality of second RX outputs are disposed on a second side of the transceiver.

6. 6. The LIDAR sensor system of claim 5, wherein the plurality of LO inputs and the plurality of TX inputs are located between (1) the plurality of first RX outputs and (2) the plurality of second RX outputs.

7. a first detector that outputs the plurality of first return lights and the plurality of first LO signals; a second detector to which the plurality of second return lights and the plurality of second LO signals are output; The LIDAR sensor system of claim 1 further comprising:

8. The transceiver includes: a first semiconductor substrate including the plurality of TX outputs; a second semiconductor substrate including the plurality of RX inputs; The LIDAR sensor system of claim 1 further comprising:

9. 9. The LIDAR sensor system of claim 8, wherein the first semiconductor substrate and the second semiconductor substrate are arranged at an interval corresponding to a pitch of the plurality of TX outputs or a pitch of the plurality of RX inputs.

10. 1. An autonomous vehicle control system for an autonomous vehicle, comprising: a light detection and ranging (LIDAR) sensor system including a transceiver; one or more processors; Equipped with The transceiver includes: a plurality of inputs configured to receive a plurality of local oscillator (LO) signals and a plurality of optical signals received from a laser source; a plurality of transmit (TX) outputs configured to transmit the plurality of optical signals to an environment of the autonomous vehicle via the plurality of TX outputs; a plurality of receive (RX) inputs configured to receive a plurality of first return lights and a plurality of second return lights reflected from one or more objects in the environment; a plurality of first RX outputs configured to receive the plurality of first return lights and a plurality of first LO signals among the plurality of LO signals in correspondence with each other; a plurality of second RX outputs configured to receive the plurality of second return lights and a plurality of second LO signals among the plurality of LO signals in correspondence with each other; Including, the one or more processors are configured to control operation of an autonomous vehicle using the plurality of first return lights and the plurality of first LO signals.

11. 11. The autonomous vehicle control system of claim 10, wherein the plurality of TX outputs and the plurality of RX inputs are provided on a first side of the transceiver.

12. The plurality of inputs include: a plurality of LO inputs through which the plurality of LO signals are provided to the transceiver; a plurality of TX inputs through which the plurality of optical signals are provided to the transceiver; 12. The autonomous vehicle control system of claim 11, comprising:

13. The autonomous vehicle control system of claim 12 , wherein the plurality of LO inputs, the plurality of TX inputs, and the plurality of first RX outputs are located on a second side of the transceiver.

14. 13. The autonomous vehicle control system of claim 12, wherein the one or more LO inputs, the one or more TX inputs, the first plurality of RX outputs, and the second plurality of RX outputs are located on a second side of the transceiver.

15. 15. The autonomous vehicle control system of claim 14, wherein the plurality of LO inputs and the plurality of TX inputs are located between (1) the plurality of first RX outputs and (2) the plurality of second RX outputs.

16. The LIDAR sensor system includes: a first detector that outputs the plurality of first return lights and the plurality of first LO signals; a second detector to which the plurality of second return lights and the plurality of second LO signals are output; The autonomous vehicle control system of claim 10 further comprising:

17. The transceiver includes: a first semiconductor substrate including the plurality of TX outputs; a second semiconductor substrate including the plurality of RX inputs; The autonomous vehicle control system of claim 10 further comprising:

18. 18. The autonomous vehicle control system of claim 17, wherein the first semiconductor substrate and the second semiconductor substrate are arranged at an interval corresponding to a pitch of the plurality of TX outputs or a pitch of the plurality of RX inputs.

19. In autonomous vehicles, at least one of a steering system or a braking system; a light detection and ranging (LIDAR) sensor system including a transceiver; one or more processors; Equipped with The transceiver includes: a plurality of inputs configured to receive a plurality of local oscillator (LO) signals and a plurality of optical signals received from a laser source; a plurality of transmit (TX) outputs configured to transmit the plurality of optical signals to an environment of the autonomous vehicle via the plurality of TX outputs; a plurality of receive (RX) inputs configured to receive a plurality of first return lights and a plurality of second return lights reflected from one or more objects in the environment; a plurality of first RX outputs configured to receive the plurality of first return lights and a plurality of first LO signals among the plurality of LO signals in correspondence with each other; a plurality of second RX outputs configured to receive the plurality of second return lights and a plurality of second LO signals among the plurality of LO signals in correspondence with each other; Including, The one or more processors are configured to control operation of at least one of a steering system or a braking system using the plurality of first return lights and the plurality of first LO signals.

20. the plurality of TX outputs and the plurality of RX inputs are interleaved on a first side of the transceiver; 20. The autonomous vehicle of claim 19, wherein the plurality of inputs, the plurality of first RX outputs, and the plurality of second RX outputs are located on a second side of the transceiver.

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