Combining numerous functions of the LIDAR system to support vehicle operation

Abstract

Regarding LIDAR (light detection and ranging) in the field of optics, this invention provides a system and method that combines numerous functions of a LIDAR system to support vehicle operation. [Solution] The 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 an optical beam from a laser light source—the optical beam being associated with an LO (local oscillator) signal—divide the optical beam into a first split optical beam and a second split optical beam, transmit the first split optical beam and the second split optical beam to an optical device, receive a first reflected beam associated with the first split optical beam and a second reflected beam associated with the second split optical beam from the optical device, pair the first reflected beam with the LO signal and pair the second reflected beam with the LO signal.

Description

Technical Field

[0001] Cross - reference to related application(s) This application claims priority to patent application No. 16 / 915,404, filed on June 29, 2020, and currently registered as U.S. Patent No. 10,948,600, and the disclosure content of such applications is incorporated herein by reference in its entirety.

Background Art

[0002] Optical distance sensing using lasers, commonly referred to by the mnemonic LIDAR (light detection and ranging) and sometimes called RADAR, is used in a variety of applications from altimetry to photography and collision avoidance. LIDAR provides a finer - scale ranging resolution with a smaller beam size than conventional microwave ranging systems such as RADAR (radio - wave detection and ranging). Optical distance sensing is achieved by different techniques, which include direct ranging based on the round - trip travel time of light pulses to an object, chirp sensing based on the difference in frequency between a transmitted chirped optical signal and a return signal scattered from an object, and phase - coded sensing based on a single - frequency phase - change sequence distinguishable from a delay signal.

Summary of the Invention

Means for Solving the Problems

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

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

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

[0006] In other aspects, the disclosure relates to a LIDAR system comprising 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-segmented optical beam and a second-segmented optical beam. The one or more optical components are configured to transmit the first-segmented optical beam and the second-segmented optical beam to an optical device. The one or more optical components are configured to receive a first reflected beam associated with the first-segmented optical beam and a second reflected beam associated with the second-segmented optical beam from the optical device. The one or more optical components are configured to pair the first reflected beam with an LO signal and the second reflected beam with an LO signal.

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

[0008] In some implementations, one or more optical components are configured to receive an LO signal and split the LO signal into a first-partitioned LO signal and a second-partitioned LO signal. One or more optical components are configured to receive an 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 segmented LO signal and a first reflected beam to the first photodetector, causing the first photodetector to generate a first electrical signal using the first segmented LO signal and the first reflected beam. One or more optical components provide a second segmented LO signal and a second reflected beam to the second photodetector, causing the second photodetector to generate a second electrical signal using the second segmented LO signal and the second reflected beam. Crosstalk associated with the first and second electrical signals is less than -55 dB at 1 MHz and 200 MHz.

[0010] In some embodiments, the first photodetector has a pair of photodiodes, each having a common mode rejection ratio (CMRR) of 30 dB or more. The first photodetector has a bandwidth of 3 dB between 80 kHz and 650 MHz. The first photodetector has a response of 0.9 A / W (amperes per watt) or more. The light beam has the same or substantially the same operating wavelength as 1550 nanometers.

[0011] In some implementations, the LIDAR system is 5×10 -12 The system includes a transimpedance amplifier (TIA) with 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 embodiments, the LIDAR system includes a TIA with a gain between 4 kΩ and 25 kΩ. The first photodetector is configured to provide a 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 multiple outputs, each of which is 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 beam is less than 55 dB within 1 MHz and 200 MHz. In some embodiments, internal scattering of the first split beam to the first reflected beam is less than -66 dB relative to the Tx transmit power. The scattering is related to sustained polarization. In some embodiments, internal scattering of the first split beam to the first reflected beam is less than -84 dB relative to the Tx transmit power. In some embodiments, the scattering is related to flipped polarization. In some embodiments, the first split beam has a duty cycle of 33% or less.

[0014] In other respects, this disclosure relates to a method for combining multiple functions of a LIDAR system. The method includes the step of 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 step of 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 step of 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 step of 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 the optical device. The method includes the step of one or more optical components pairing the first reflected beam with an LO signal and pairing the second reflected beam with an LO signal.

[0015] In other aspects, this 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. 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. One or more LiDAR circuits are configured to split the light beam into a first split beam and a second split beam. One or more LiDAR circuits are configured to transmit the first split beam and the second split beam to an optical device. One or more LiDAR circuits are configured to receive a first reflected beam associated with the first split beam and a second reflected beam associated with the second split beam from the optical device. One or more LiDAR circuits are configured to pair the first reflected beam with the LO signal to generate a first pairing signal and to pair the second reflected beam with the LO signal to generate a second pairing signal. One or more processors are configured to use the first pairing signal and the second pairing signal to control the operation of an autonomous vehicle.

[0016] In other respects, this disclosure relates to a LIDAR system. The LIDAR system includes a laser light source and a transceiver configured to output optical signals. The transceiver includes a plurality of transmit (TX) outputs and a plurality of receive (RX) inputs, wherein optical signals are output to the environment via the plurality of transmit outputs and 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 from 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, multiple TX outputs and multiple RX inputs are interleave on the 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 and second semiconductor substrates are spaced at intervals corresponding 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, wherein one or more LO signals are supplied to the transceiver via one or more LO inputs, one or more optical signals are output to the transceiver via one or more TX inputs, and a first return light and a first LO signal are supplied to the plurality of first outputs. One or more LO outputs, one or more TX inputs, and a 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 a plurality of RX inputs, and to supply a second return light and a second LO signal from one or more LO signals to a plurality of second RX outputs. One or more LO inputs, one or more TX inputs, a plurality of first outputs, and a plurality of second RX outputs are located on a second side of the transceiver. One or more LO inputs and 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 embodiments, the LIDAR system further includes a scanner configured to receive one or more optical signals transmitted from multiple TX outputs through free space.

[0019] In other aspects, this 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 and a transceiver configured to output optical signals. The transceiver includes a plurality of transmit (TX) outputs and a plurality of receive (RX) inputs, wherein optical signals are output to the environment via the plurality of transmit outputs and 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 from 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. One or more processors are configured to use the first returned light and the first LO signal to control the operation of the autonomous vehicle.

[0020] In some embodiments, multiple TX outputs and multiple RX inputs are interleaved on the first side of the transceiver. In some embodiments, the transceiver includes a first semiconductor substrate containing multiple TX outputs and a second semiconductor substrate containing multiple RX inputs. In some embodiments, the first and second semiconductor substrates are spaced apart to correspond 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, wherein one or more LO signals are supplied to the transceiver via one or more LO inputs, one or more optical signals are output to the transceiver via one or more TX inputs, and a first return light and a first LO signal are supplied to the plurality of first outputs. One or more LO outputs, one or more TX inputs, and a 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 a plurality of RX inputs, and to supply a second return light and a second LO signal from one or more LO signals to a plurality of second RX outputs. One or more LO inputs, one or more TX inputs, a plurality of first outputs, and a plurality of second RX outputs are located on a second side of the transceiver.

[0022] In other aspects, this disclosure relates to an autonomous vehicle. The autonomous vehicle includes at least one of a steering system or braking system, a LiDAR system, and at least one processor. The LiDAR system includes a laser light source and a transceiver configured to output optical signals. The transceiver includes a plurality of transmit (TX) outputs and a plurality of receive (RX) inputs, wherein optical signals are output to the environment via the plurality of transmit outputs and 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 from 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. One or more processors are configured to use the first returned light and the first LO signal to control the operation of at least one of the steering system or braking system.

[0023] Other aspects, features, and advantages should be readily understood from the following detailed description, including the best mode contemplated before carrying out the invention and explaining a number of specific embodiments. Note that other embodiments also have features and advantages different from other features, and many details can be varied and clarified without departing from the spirit and scope of the invention. Therefore, the drawings and description are illustrative in nature and should not be considered restrictive.

Brief Description of the Drawings

[0024] The embodiments are illustrated as examples and not as limitations, and the same reference numerals in the accompanying drawings refer to the same components. [Figure 1a] FIG. 1 is a block diagram showing an example of a system environment for an autonomous vehicle according to some embodiments. [Figure 1b] FIG. 2 is a block diagram showing an example of a system environment for a commercial autonomous truck according to some embodiments. [Figure 1c] FIG. 3 is a block diagram showing an example of a system environment for a commercial autonomous truck according to some embodiments. [Figure 1d] FIG. 4 is a block diagram showing an example of a system environment for a commercial autonomous truck according to some embodiments. [Figure 2] FIG. 5 is a block diagram showing an exemplary environment of a LIDAR system for an autonomous vehicle according to some embodiments. [Figure 3] FIG. 6 is a block diagram showing an exemplary coherent LIDAR transceiver for vehicle operation according to some embodiments. [Figure 4] FIG. 7 is a block diagram showing an exemplary coherent LIDAR transceiver of two semiconductor substrates according to some embodiments. [Figure 5] FIG. 8 is a flowchart showing an exemplary method of combining a number of functions of a LIDAR system according to an embodiment.

Modes for Carrying Out the Invention

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

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

[0027] The receiving (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. To determine the distance to an object and / or measure the speed of an object, the Rx path provides the down-converted (now amplified) signal to the autonomous vehicle control system.

[0028] In conventional LiDAR systems, fiber coupling (sometimes referred to as "fiber cab") connects the Tx path, Rx path, and optical instruments to each other. Fiber coupling provides flexibility during the 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 the fiber couplings limits LiDAR designers' ability to add additional channels—each requiring more fiber couplings—and / or reduce the size of LiDAR systems to a size that is efficient and required for automotive applications.

[0030] Therefore, this disclosure relates to a system and method for assisting vehicle operation by combining multiple functions of a LIDAR system (e.g., splitting, acquisition, merging, redirecting, pairing, etc.).

[0031] As described below, the Tx path of a multi-channel coherent LiDAR transceiver receives a light beam from a laser source (via the Tx input). The laser source generates a light beam based on the LO signal. The Tx path of the coherent LiDAR transceiver splits the light beam into multiple light paths (e.g., multiply, duplicate, regenerate, etc.) 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 the return light reflected by the Rx waveguides from one or more objects (via the Rx input). Each Rx waveguide is paired with each 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] The various exemplary embodiments 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, but these inputs improve matching with the LiDAR engine architecture; (2) The Tx / Rx output to free space occurs along one edge of the coherent LiDAR transceiver, where the waveguide interleaves with the Tx / Rx output (e.g., Tx-Rx-Tx-Rx), and the pitch is determined by the requirements for free-space circulation and / or by beam collimation optics. (3) The LO and Tx inputs are paired (e.g., LO_A, LO_B; Tx_A, Tx_B, etc.) and function as independent subsystems; (4) The input power level to the Tx input is high (e.g., >1 watt each); (5) The fiber coupling to the coherent LIDAR transceiver input receives high power; (6) Scattering of the Tx path to the Rx path (e.g., towards the detector) (sometimes referred to as "directional") is very small while interleaved; (7) Reflections from the output surface are minimized (e.g., angled gloss of the coherent LIDAR transceiver). (8) When the output beam quality is defined as the waveguide output, the output of the coherent LIDAR transceiver should also have high quality modes (e.g., low distortion from the transverse electromagnetic (TEMOO) beam); (9) The functions of the LIDAR system (e.g., splitting, acquisition, coupling, redirection, pairing, etc.) are coupled into a single integrated photonic device; (10) The coherent LIDAR transceiver is implemented using a PLC (programmable logic controller).

[0033] In the above description, various specific details have been presented for illustrative purposes to provide a complete understanding of embodiments of the present invention. However, it will be apparent to those skilled in the art that the disclosure can be implemented without such specific details. In other examples, known structures and apparatus are shown in block diagrams to avoid unnecessarily obscuring the disclosure.

[0034] 1. System environment of autonomous vehicles Figure 1a is a block diagram showing an example of a system environment for an autonomous vehicle, partially implemented.

[0035] Referring to Figure 1a, an exemplary autonomous vehicle 100 embodies a variety of techniques disclosed herein. For example, the vehicle 100 includes a powertrain 102 that powers a drivetrain 108, a prime mover 104 powered by an energy source 106, and a control system 110 that includes a direction control 112, a powertrain controller 114, and a brake controller 116. The vehicle 100 embodies a variety of forms, including vehicles that transport people and / or cargo and operate in a variety of environments, but it should be understood that the components 102 to 116 described above can vary widely depending on the type of vehicle in which these components are used.

[0036] For simplicity, the embodiments discussed below will focus on wheeled land vehicles, such as passenger cars, vans, trucks, and buses. In such embodiments, the prime mover 104 includes one or more electric motors and / or internal combustion engines (among others). Energy sources include, for example, fuel systems (providing gasoline, diesel, hydrogen, etc.), battery systems, solar panels, and other renewable energy sources and / or fuel cell systems. The drivetrain 108 includes one or more brakes configured to controllably stop or reduce the speed of the vehicle, and wheels and / or tires that work with a transmission and / or any other mechanical drive components, as well as a directional or steering component suitable for controlling the trajectory of the vehicle 100 (e.g., a rack and pinion steering coupling such that one or more wheels of the vehicle 100 generally rotate with respect to a vertical axis so that the rotational plane angle of the wheels changes with respect to the long axis of the vehicle), as well as a transmission and / or any other mechanical drive component that converts the output of the prime mover 104 into vehicle motion. In some implementations, a combination of powertrain and energy source is used (for example, in electric / gas hybrid vehicles), and in some examples, a number of electric motors (for example, 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 direction or steering components to ensure that the vehicle 100 follows a desired trajectory. The power controller 114 controls the output of the powertrain 102 and is configured to control, for example, the output power of the prime mover 104 to control the drive and gears of the transmission in the traction 108, thereby controlling the speed and / or direction of the vehicle 100. The brake controller 116 is configured to control one or more brakes that reduce the speed or stop the vehicle, for example, disc or drum brakes coupled to the wheels of the vehicle.

[0038] Other vehicle types, including but not limited to off-road vehicles, all-terrain or tracked vehicles, and construction equipment, inevitably use different powertrains, drivetrains, energy sources, direction controllers, powertrain controllers, and brake controllers. Furthermore, some components are combined in some embodiments; for example, rearward control of the vehicle is primarily handled by varying the output of one or more prime movers. Therefore, the embodiments 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 the vehicle 100 are embodied in the vehicle control system 120, which includes one or more processors 112 and one or more memories 124, each processor 122 configured to execute program code instructions 126 stored in the memory 124. The processors include, for example, graphics processing units ("GPU(s)") and / or central processing units ("CPU(s)").

[0040] Sensor 130 includes a variety of sensors adapted for collecting information from the vehicle's surrounding environment used to control the vehicle's operation. For example, sensor 130 includes a radar sensor 134, a LiDAR sensor 136, and a 3D positioning sensor 138 which is, for example, an accelerometer, gyroscope, magnetometer, or one of the following satellite navigation systems: GPS, GLONASS (Globalnaya Navigazionnaya Sputnikovaya Sistema, 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. Sensor 130 also includes a camera 140 and / or an IMU (inertial measurement unit) 142. The camera 140 is a monographic or stereographic camera that records still images and / or video. The IMU 142 includes multiple gyroscopes and accelerometers to 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 output of sensor 130 is provided to a control subsystem set 150, which includes a localization subsystem 152, a planning subsystem 156, a recognition subsystem 154, and a control subsystem 158. The localization subsystem 152 functions to accurately determine the position and orientation (sometimes referred to as "attitude") of vehicle 100 within its surrounding environment and within approximately a certain number of reference frames. The position of the autonomous vehicle is part of the data generation of labeled autonomous vehicles and is compared to the positions of additional vehicles in the same environment. The recognition subsystem 154 functions to detect, track, determine, and / or identify objects in the environment surrounding vehicle 100. A machine learning model with some embodiment is used for object tracking. The planning subsystem 156 functions to plan the trajectory for vehicle 100 for a given number of time frames, where a desired destination is given, as well as objects that are stationary or moving in the environment. A machine learning model with some embodiment is used for object tracking planning. The controller subsystem 158 functions to generate appropriate controller signals for controlling various controllers in the controller system 120 in order to realize the planned trajectory of the vehicle 100. A machine learning model is used to generate one or more signals to control the autonomous vehicle and realize the planned trajectory.

[0042] It should be understood that the component collection shown in Figure 1a for the vehicle control system 120 is essentially illustrative. Individual sensors are omitted in some embodiments. Additionally or alternatively, in some embodiments, the various types of sensors shown in Figure 1 are used in overlapping and / or to cover different areas around the vehicle, but other types of sensors may be used. Similarly, different types and / or combinations of control subsystems may be used in other embodiments. Also, although subsystems 152 to 158 are shown to be separate from the processor 122 and memory 124, it should be understood that in some embodiments, some or all of the functions of subsystems 152 to 158 are embodied by program code instructions 126 residing in one or more memories 124 and executed by one or more processors 122, and in some examples, these subsystems 152 to 158 are embodied using the same processor(s) and / or memory. The subsystems are embodied, at least partially, using diverse dedicated circuit logic, diverse processors, diverse FPGAs (field programmable gate arrays), diverse ASICs (application-specific integrated circuits), diverse real-time controllers, and so on. As mentioned above, numerous subsystems utilize circuits, processors, sensors, and / or other components. Furthermore, the diverse components within the vehicle control system 120 are networked in diverse ways.

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

[0044] A multitude of different architectures, including diverse combinations of software, hardware, circuit logic, sensors, and networks, are used to embody the various components illustrated in Figure 1a. Each processor is embodied, for example, by a microprocessor, and each memory is embodied by a RAM (random access memory) device including main storage, as well as supplemental level memory such as cache memory, non-volatile or backup memory (e.g., programmable or flash memory), and ROM (read-only memory). Furthermore, each memory is considered to be virtual memory, including not only storage capacity used as, for example, a large storage device or other computer or controller, but also memory storage physically located somewhere within the vehicle 100, such as any cache memory within the processor. One or more processors shown in Figure 1a, or processors that are isolated as a whole, are used to embody additional functions within the vehicle 100 beyond the purpose of autonomous control, such as the control of entertainment systems, doors, lighting, convenience features, and other operations.

[0045] In addition, for additional storage, the vehicle 100 may include one or more large-capacity storage devices, such as removable disk drives, hard disk drives, "DASDs" (direct access storage devices), optical drives (e.g., CD drives, DVD drives, etc.), "SSDs" (solid state storage drives), network-mounted storage, storage area networks, and / or tape drives.

[0046] Furthermore, the vehicle 100 includes a user interface 164 to enable the vehicle 100 to receive a number of inputs from a user or operator and to generate outputs for the user or operator, such as one or more displays, touchscreens, voice and / or gesture interfaces, buttons, and other haptic controls. Otherwise, user input is received via other computers or electronic devices, such as apps on portable devices or via web interfaces.

[0047] Furthermore, the vehicle 100 includes one or more network interfaces, e.g., network interface 162, that are compatible with communication with one or more networks 170 (e.g., LAN (Local Area Network), WAN (Wide Area Network), wireless network, and / or the Internet), and allows communication of information with other computers and electronic devices, including, for example, a central service such as a cloud service that receives environment and other data for use by the vehicle 100 for autonomous control. Data collected by one or more sensors 130 is uploaded to the computing system 172 via the network 170 for other processing. In some embodiments, a timestamp is added to each instance of the vehicle data before uploading.

[0048] Each processor shown in Figure 1a, as well as the various additional controllers and subsystems described herein, operates under a general operational structure as described in detail below, executing or depending on various computer software applications, components, programs, objects, modules, data structures, etc. Furthermore, these various applications, components, programs, objects, and modules also run on one or more processors on other computers connected to the vehicle 100 via network 170 in a distributed, cloud-based, or client-server computing environment, thereby allocating the processing necessary to realize the functionality of the computer programs to numerous computers and / or services via the network.

[0049] Routines performed to embody the various embodiments described herein are referred to herein as “program code,” depending on whether they are embodied in an operational structure or in a specific application, component, program, object, module, or instruction sequence, or a subset thereof. Program code resides in various memories and storage devices of a computer at various times and, when read or executed by one or more processors, contains one or more instructions that perform the steps necessary to execute steps or elements that embody various aspects of this disclosure. Furthermore, the embodiments are described in the context of fully functioning computers and systems, and as will be discussed later, the various embodiments described herein may be distributed in various forms as program products, and it should be understood that the embodiments are embodied regardless of the specific type of computer-readable medium used to actually carry out this distribution.

[0050] Examples of computer-readable media include, among others, volatile and non-volatile memory devices, floppy disks and other removable disks, SSDs (solid-state drives), hard disk drives, magnetic tapes and optical discs (e.g., CD-ROMs, DVDs, etc.), which are tactile and non-temporary media.

[0051] Furthermore, the various program codes described later are identified based on the applications embodied in specific embodiments. However, the names of any particular programs described later are merely for convenience, and this disclosure should not be limited to any specific application identified and / or implied by such names. It should also be understood that this disclosure is not limited to the specific organization and assignment of program functions described herein, as there are countless ways in which computer programs are organized into routines, procedures, methods, modules, objects, etc., as well as various ways in which program functions are assigned to the various software hierarchies that reside in a typical computer (e.g., operational structures, libraries, APIs, applications, applets, etc.).

[0052] The environment shown in Figure 1a is not intended to limit the embodiments disclosed herein. Indeed, other alternative hardware and / or software environments may be used without exceeding the scope of the embodiments disclosed herein.

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

[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, objects (e.g., pedestrians wearing dark clothing) have low reflectivity, meaning that a small amount of light (e.g., less than 10%) that hits the object is reflected back to the sensor (e.g., sensor 130 in Figure 1a) of the FM or PM LiDAR system. In other examples, objects (e.g., road signs) have high reflectivity, meaning that a large amount of light that hits the object is reflected back to the sensor (e.g., more than 10%) of the FM or PM LiDAR system.

[0055] Regardless of the object's reflectivity, FM LiDAR systems can detect objects at greater distances (e.g., 2x) than conventional LiDAR systems (e.g., for classification, recognition, and discovery). For example, an FM LiDAR system can detect low-reflectivity objects at 300 meters away and high-reflectivity objects at 400 meters away.

[0056] To achieve such improvements in detection capability, FM LIDAR systems utilize sensors (e.g., sensor 130 in Figure 1a). In some embodiments, such sensors are sensitive to single photons, meaning they can detect even 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 the infrared wavelength range (e.g., near-infrared: 800 nm–1500 nm; mid-infrared: 1500 nm–5600 nm; and far-infrared: 5600 nm–1,000,000 nm). By operating FM or PM LIDAR systems at infrared wavelengths, they can 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 limitations on light output (and distance detection capability) for eye safety reasons.

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

[0058] Another advantage of FM LIDAR systems is that they provide instantaneously accurate 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 either radial velocity (e.g., the direction vector between the detected object and the sensor) or the frequency of the laser signal. For example, at on-road speeds of less than 100 m / s, such a shift at a wavelength of 1550 nanometers (nm) corresponds to a frequency shift of less than 130 MHz. Such frequency shifts are too small to be directly detected in the optical domain. However, by using coherent detection in FMCW, PMCW, or FMQW LIDAR systems, the signal is converted to the RF domain so that its frequency shift is calculated using various signal processing techniques. This allows autonomous vehicle control systems to process the input data more quickly.

[0059] The calculation of instantaneous velocity also makes it easier for FM LiDAR systems to determine rare data points as distance or objects, and / or track how those points move over time. For example, an FM LiDAR sensor (e.g., sensor 130 in Figure 1a) may receive only a few returns (e.g., hits) from an object 300m away, but if those returns provide a velocity value of interest (e.g., moving towards a vehicle at a speed of >70mph), the FM LiDAR system and / or the autonomous vehicle control system can determine the respective weights for the probabilities associated with the object.

[0060] Faster identification and / or tracking by FM LiDAR systems provides autonomous vehicle control systems with more time to activate the vehicle. Better knowledge of how fast objects are moving also allows autonomous vehicle control systems to plan better responses.

[0061] Another advantage of FM LIDAR systems is that they are less static than conventional LIDAR systems. That is, conventional LIDAR systems, designed to be more sensitive to light, typically operate poorly in bright sunlight. Such systems are also prone to crosstalk (e.g., when sensors are confused by each other's light pulses or beams) and self-interference (e.g., when sensors are confused by their own previous light pulses or beams). To overcome these shortcomings, vehicles using conventional 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 problems because each sensor is designed to respond only to its own optical characteristics (e.g., light beam, light wave, light pulse). If the return light does not match the timing, frequency, and / or wavelength to which it was originally transmitted, the FM sensor filters out that data point (e.g., remove, ignore, etc.). Such FM LiDAR systems produce more accurate data (e.g., generate, derive) with less hardware or software, enabling safer and smoother operation.

[0062] Finally, FM LiDAR systems are easier to size-control than conventional LiDAR systems. As more autonomous vehicles (e.g., cars, commercial trucks) appear on the road, vehicles equipped with FM LiDAR systems will not have to deal with interference problems caused by sensor crosstalk. Furthermore, FM LiDAR systems use less peak optical power than conventional LiDAR sensors. Some or all of the optical components for such FM LiDAR are produced on a single chip, creating unique advantages as discussed herein.

[0063] 2.1 Commercial Trucks Figure 1b is a block diagram showing an example of a system environment for a commercial autonomous truck in some embodiment. Environment 100B includes a commercial truck 102B for transporting cargo 106B. In some embodiment, the commercial truck 102B includes a vehicle configured for long-distance freight transport, regional freight transport, intermodal freight transport (i.e., transport in which a road-based vehicle is used as one of several modes of transport for moving cargo), and / or other road-based freight transport applications. In some embodiments, commercial truck 102B includes flatbed trucks, refrigerated trucks (e.g., reefer trucks), vented vans (e.g., dry vans), and mobile trucks. In some embodiments, cargo 106B is goods and / or products. In some embodiments, commercial truck 102B includes trailers for transporting cargo 106B, such as platform trailers, lowboy trailers, step deck trailers, expandable platform trailers, and sidekit trailers.

[0064] Environment 100B includes object 110B (illustrated as another vehicle in Figure 1b) located within a distance of 30 meters or less from the truck.

[0065] The commercial truck 102B includes a LiDAR system 104B (e.g., the FM LiDAR system in Figure 1a, the vehicle control system 120, the LiDAR system 201 in Figure 2) for determining the distance to object 110B and / or measuring the speed of object 110B. Figure 1b shows one LiDAR system 104B mounted on the front of the commercial truck 102B, but the number of LiDAR systems on the commercial truck and the mounting area of ​​the LiDAR systems are not limited to a specific number or area. The commercial truck 102B includes 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., front, rear, sides, top, bottom, underside, and / or bottom), facilitating the detection of objects in any free space relative to the commercial truck 102B.

[0066] As illustrated, the LIDAR system 104B in environment 100B is configured to detect objects (e.g., other vehicles, bicycles, trees, street signs, potholes, etc.) at close range (e.g., 30 meters or less) from the commercial truck 102B.

[0067] Figure 1c is a block diagram showing an example of a system environment for a commercial autonomous truck, partially realized. Environment 100C includes the same components as environment 100B (e.g., commercial truck 102B, cargo 106B, LIDAR system 104B, etc.).

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

[0069] Figure 1d is a block diagram showing an example of a system environment for a commercial autonomous truck, partially realized. Environment 100D includes the same components as environment 100B (e.g., commercial truck 102B, cargo 106B, LIDAR system 104B, etc.).

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

[0071] In commercial truck applications, it is crucial to effectively detect objects over the entire range due to increased weight and the resulting 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 mentioned above. As a result, commercial trucks equipped with such systems have an improved ability to safely transport people and goods over short or long distances, thus improving the safety of not only the commercial truck but also surrounding vehicles. In various embodiments, such FM or PM LiDAR systems are used in semi-autonomous driving applications where a driver is present in 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 where the commercial truck operates entirely with 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 a LiDAR system using CW modulation, the modulator continuously modulates the laser beam. For example, if the modulation cycle is 10 seconds, the input signal is modulated for the entire 10 seconds. Alternatively, in a LiDAR system using quasi-continuous wave modulation, the modulator modulates the laser beam in an active and inactive phase. For example, in the case of 10 cycles, the modulator modulates the laser beam for only 8 seconds (sometimes referred to as the "active phase"), and does not modulate the laser beam for 2 seconds (sometimes referred to as the "inactive phase"). This allows the LiDAR system to reduce power consumption by 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 Lidar systems using quasi-CW modulation where FMCW measurement and signal processing methods are employed, although the optical signal is not always in an on state (e.g., enabled, powered on, transmitting). In some embodiments, quasi-CW modulation has duty cycles of 1% or more and up to 50%. If energy is required during the actual measurement time in an off state (disabled, powered down, etc.), there may be a boost to the signal-to-noise ratio (SNR) and / or a reduction in the signal processing requirements for coherently integrating all energy over longer time domains.

[0074] 4. Coherent Lidar transceiver with multiple channels Figure 2 is a block diagram illustrating an exemplary environment for a LiDAR system for an autonomous vehicle, as partially realized. Environment 200 includes a LiDAR system 201, which includes 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 substrate and / or semiconductor package includes Tx paths and Rx paths. In some embodiments, the first semiconductor substrate and / or first semiconductor package includes Tx paths, and the second semiconductor substrate and / or second semiconductor package includes Rx paths. In some arrangements, 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., a vibrating scanner, a unidirectional scanner, a Risley prism, a circulator optical instrument, and / or a beam collimator) coupled to the LIDAR system 201. In some embodiments, one or more optical instruments 210 are coupled to a Tx path via one or more Tx input / output ports. In some embodiments, one or more optical instruments 210 are coupled to an Rx path via one or more Rx input / output ports.

[0077] Environment 200 includes a vehicle control system (e.g., vehicle control system 120 in Figure 1) coupled to a LiDAR system. In some embodiments, the vehicle control system 120 is coupled to an Rx path via one or more Rx input / output ports.

[0078] The Tx path includes a laser light source 202, modulator 204A, modulator 204B, and amplifier 206. The Rx path includes a mixer 208, detector 212, and TIA 212. Figure 2 shows a selected number of components and just one input / output channel, but environment 200 includes any number of components and / or input / output channels linked to each other in any array (any combination), facilitating the combination of numerous functions of the LIDAR system to support vehicle operation.

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

[0080] The laser light source 202 is configured to provide an optical signal to the modulator 204A, which is configured to modulate the phase and / or frequency of the optical signal using CW modulation or quasi-CW modulation based on a first RF (radio frequency) signal (illustrated as "RF1" in Figure 2) to produce a modulated optical signal. The modulator 204A is configured to transmit the modulated optical signal to the amplifier 206, which is configured to amplify the modulated optical signal to produce an amplified optical signal for the optical instrument 210.

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

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

[0083] Mixer 208 mixes (e.g., combines, amplifies, etc.) the modulated LO signal with the return signal to generate a down-converted signal, which is then transmitted to detector 212. In some arrays, mixer 208 is configured to transmit the modulated LO signal to detector 212.

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

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

[0086] In some embodiments, TIA 214 is 5 picowatts per square root of Hertz (i.e., 5 × 10⁻¹⁴ per square root of Hertz). -12 It has a peak NEP (noise-equivalent power) of less than watts. In some embodiments, the TIA 214 has a gain between 4 kΩ and 25 kΩ.

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

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

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

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

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

[0092] The laser light source provides the LO signal (modulated or unmodulated) to the LO input 366 (indicated as "LOA-B" in Figure 3). The coherent LiDAR transceiver 301 splits the LO signal received from the LO input 366 into LO signal 366-1 and LO signal 366-2. The coherent LiDAR transceiver 301 splits LO signal 366-1 into LO signal 366-1a and LO signal 366-1b. The coherent LiDAR transceiver 301 splits LO signal 266-2 into LO signal 366-2a and LO signal 366-2b.

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

[0094] The laser light source provides an optical signal (modulated or unmodulated) to the Tx input 364 (indicated as "Tx-B" in Figure 3). The coherent LiDAR transceiver 301 splits the optical signal received from the Tx input 364 into optical signal 364-1 and optical signal 364-2. The coherent LiDAR transceiver 301 splits optical signal 364-1 into optical signal 364-1a and optical signal 364-1b. The 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 via the Tx output 320 toward one or more objects, receives the return light reflected from the objects via the Rx input 322, and provides the return light and LO signal 360-2b to a detector 303 (illustrated as "RX-1" in Figure 3). The detector 303 generates an electrical signal based on the return light and / or LO signal 360-2b.

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

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

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

[0099] The coherent LIDAR transceiver 301 emits an optical signal 364-1a into free space via the Tx output 336 toward one or more objects, receives the return light reflected from the objects via the Rx input 338, and provides the return light and the LO signal 366-2b to a detector 307 (illustrated as "Rx-1" in Figure 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 via the Tx output 340 toward one or more objects, receives the return light reflected from the objects via the Rx input 342, and provides the return light and LO signal 366-2a to a detector 308 (illustrated as "Rx-2" in Figure 3). The detector 308 generates an electrical signal based on the return light and / or LO signal 366-2a.

[0101] The coherent LIDAR transceiver 301 emits an optical signal 364-2a into free space via the Tx output 344 toward one or more objects, receives the return light reflected from the objects via the Rx input 346, and provides the return light and the LO signal 366-1b to a detector 309 (illustrated as "Rx-1" in Figure 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 toward one or more objects, receives the 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 Figure 3). The detector 310 generates an electrical signal based on the return light and / or LO signal 366-1a.

[0103] In some embodiments, signal crosstalk related to the return light (sometimes referred to as the "return beam") returned from the internal surface to the LIDAR sensor, and the emission 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.) are less than -55 dB within 1 MHz and 200 MHz in all other channels relative to the channel in which the reflected beam is acquired.

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

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

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

[0107] In some embodiments, one or more detectors 303 to 301 include a pair of photodiodes. In some embodiments, the pair of photodiodes in the detector has a CMRR of 30 dB or more.

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

[0109] In some embodiments, one or more detectors 303 to 310 have a responsibility of 0.9 A / W or higher.

[0110] In some implementations, one 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.) has a duty cycle of 33% or less.

[0111] Figure 4 is a block diagram illustrating an exemplary coherent LiDAR transceiver on two semiconductor substrates in a partial embodiment. The environment 400 includes a semiconductor substrate 402 containing the Rx / LO path and a semiconductor substrate 404 containing the Tx path. The semiconductor substrates 402 and 404 are arranged consecutively at an interval "A" close to the pitch (e.g., the distance between the centers of the two input / outputs) in the concept of a single chip. In the partial embodiment, the input / output of each semiconductor substrate has a pitch between 31.75 micrometers and 381 micrometers.

[0112] Figure 5 is a flowchart illustrating an exemplary method for combining multiple functions of a LiDAR system in an embodiment. In Figure 5, the steps are shown as integrated steps in a specific order for illustrative purposes, but in other embodiments, one or more steps or parts thereof may be performed directly or in parallel, in a different order or superimposed in time, or omitted, or one or more additional steps may be added, or the method may be modified by combining some of the schemes. In some embodiments, some or all of the operation of method 500 is performed by the coherent LiDAR transceiver 301 of Figure 3.

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

[0114] The above description is provided so that a person skilled in the art can implement the various aspects described herein. Various modifications to such aspects are obvious to a person skilled in the art, and the generic principles defined herein apply to other aspects. Thus, the claims are not limited to the aspects shown herein, but are intended to conform to the overall scope that coincides with the linguistic claims, and the singular designation of a component herein does not mean “one and just one” unless expressly so, but rather “one or more.” Unless expressly otherwise, the term “part” refers to one or more. All structural and functional equivalents to the components of the various aspects known to a person skilled in the art or described through a publicly known description are explicitly integrated as this reference and achieved by this claim. Furthermore, nothing disclosed herein is designated as common, regardless of whether such disclosure is expressly referred to in the claims or not. Any component of any claim should be construed as a means and function unless the component is expressly referred to as a “means.”

[0115] It should be understood that certain sequences or hierarchical structures of blocks within the disclosed process are examples of descriptive approaches. Based on design preferences, it should be understood that certain sequences of steps within the process or hierarchical structures of blocks may be rearranged while maintaining the scope of the above description. The accompanying method requests the current components of various blocks in the order of the sample and does not mean that they are limited to the specific sequence or hierarchical structure presented.

[0116] The above-mentioned descriptions of the disclosed embodiments are provided so that a person skilled in the art may construct or use the gist of the disclosed invention. Various modifications to such embodiments will be obvious to a person skilled in the art, and the general principles defined herein will apply to other embodiments without departing from the idea or scope of the above-mentioned descriptions. Thus, the above-mentioned descriptions are not intended to be limited to the embodiments presented herein, but rather to conform to the broadest extent that is consistent with the principles and novel features disclosed herein.

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

[0118] The above-described method and processor flowchart are provided merely as illustrative examples and do not require or suggest that the blocks in the various examples must be performed in the order presented. Those skilled in the art will understand that in the above-described examples, the blocks may be performed in any order. Words such as "then," "then," and "next" do not restrict the order of the blocks. These words are used simply to guide the reader by describing the method. Furthermore, any reference to a singular claim component should not be construed as limiting the component to a singular form.

[0119] The various exemplary logic blocks, modules, circuits, and algorithmic steps described herein are embodied as electronic hardware, computer software, or a combination thereof. To clearly illustrate the interoperability of hardware and software, various exemplary components, blocks, modules, circuits, and steps are generally described above in terms of their functionality. Whether such functionality is embodied as hardware or software depends on the design constraints imposed on the overall system and the specific application. Those skilled in the art may embody the described functionality by varying the methods for each specific application, but such a decision should not be construed as exceeding the scope of this disclosure.

[0120] The various exemplary logic blocks, modules, and circuits described in relation to the disclosures herein are embodied or performed by general-purpose processors, DSPs, ASICs, FPGAs, or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination designed to perform the functions described herein. While a general-purpose processor is a microprocessor, alternatively, a processor may be any conventional processor, controller, microcontroller, or state machine. Furthermore, a processor may be a combination of computing devices, embodied, for example, a DSP and a microprocessor, multiple microprocessors, one or more microprocessors having a DSP core, or any other combination of such configurations. Alternatively, some blocks or methods may be performed by circuits identified to perform a given function.

[0121] In some exemplary examples, the described functions are embodied in hardware, software, firmware, or any combination thereof. Where embodied as software, the functions are stored as one or more instructions or codes on a non-temporary computer-readable storage medium or a non-temporary processor-readable storage medium. Blocks of methods or algorithms disclosed herein are embodied in software modules executable by a processor residing on a non-temporary computer-readable storage medium or a non-temporary processor-readable storage medium. A non-temporary computer-readable storage medium or a non-temporary processor-readable storage medium is any storage medium accessed by a computer or processor. For example, but not limited to, such non-temporary computer-readable storage mediums or non-temporary 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 for storing desired program code in the form of instructions or data structures. The terms "disk" and "disc" used herein include CDs (compact discs), laserdiscs, optical discs, DVDs (digital versatile discs), floppy disks (disks), and Blu-ray discs, where a disk typically reproduces data magnetically, while a disc uses a laser to reproduce data optically. Combinations of the above also fall within the range of non-temporary computer-readable and processor-readable media. Furthermore, the operation of a method or algorithm resides permanently as one or any combination or set of code and / or instructions on a non-temporary processor-readable and / or computer-readable storage medium, which may be integrated within a computer program product.

[0122] The above-mentioned descriptions of the disclosed examples are provided so that a person skilled in the art may make or use the disclosure. Various modifications to such examples are obvious to a person skilled in the art, and the general principles defined herein apply to other embodiments without departing from the idea or scope of the above-mentioned descriptions. Thus, the above-mentioned descriptions are not intended to be limited to the embodiments presented herein, but should conform to the broadest extent that is consistent with the principles and new features disclosed herein.

[0123] Although the numerical ranges and parameters presented are approximations, the numerical values ​​presented in non-restrictive examples are reported as accurately as possible. However, all numerical values ​​inherently contain certain errors resulting from the standard deviation found in each test measurement when drafting this specification. Furthermore, unless otherwise specifically stated in the context, the numerical values ​​presented herein have an implied precision given by the least significant digit. Thus, a value of 1.1 means a value between 1.05 and 1.15. The term “approximately” is used to indicate a broader range around a given value, but unless otherwise specified in the context, it means a broader range around the least significant digit, such as “approximately 1.1” meaning a value between 1.0 and 1.2. If the least significant digit is unclear, the term “approximately” means a factor of two. For example, “approximately X” means a value between 0.5X and 2X. For example, approximately 100 means a value between 50 and 200. Furthermore, all ranges disclosed herein should be understood to include any and all subranges contained therein. For example, the range "less than 10" includes any and all subranges between (and including) the minimum value 0 and the maximum value 10. That is, it includes any and all ranges that have a minimum value equal to or greater than 0, and a maximum value equal to or less than 10 (e.g., 1 to 4).

[0124] While 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 of a personal vehicle (e.g., front, rear, side, top, and / or bottom), embodiments are not limited to this context. Other embodiments employ one or more systems of the same type, or other high-resolution LiDARs with or without superimposed or unsuperimposed fields of view, or one or more such systems, large or small, mounted on a driver-operated or autonomous ground, sea vehicle, or aerial aircraft. Other embodiments involve scanning high-resolution LiDARs mounted in temporarily or permanently fixed positions on the ground or sea. [Item of the invention] [Item 1] In a LIDAR (light detection and ranging) system including a semiconductor substrate and one or more optical components attached to the semiconductor substrate, the one or more optical components are: A light beam is received from a laser light source - the light beam is associated with the LO (local oscillator) signal - The aforementioned light beam is divided into a first divided light beam and a second divided light beam. The first split light beam and the second split light beam are transmitted to the optical device. The optical device receives the first reflected beam associated with the first divided light beam and the second reflected beam associated with the second divided light beam, A LIDAR system configured to pair the first reflected beam with the LO signal and the second reflected beam with the LO signal. [Item 2] The one or more optical components mentioned above are: A second light beam generated by the laser light source or the second laser light source is received - the second light beam is associated with the LO signal - The second light beam is divided into a third-divided light beam and a fourth-divided light beam. The third-segmented light beam and the fourth-segmented light beam are transmitted to the optical device. The optical device receives the third reflected beam associated with the third divided light beam and the fourth reflected beam associated with the fourth divided light beam, The LIDAR system according to item 1, further configured to pair the third reflected beam with the second LO signal and the fourth reflected beam with the second LO signal. [Item 3] The one or more optical components mentioned above are: Upon receiving the aforementioned LO signal, The LIDAR system according to item 1, further configured to divide the aforementioned LO signal into a first divided LO signal and a second divided LO signal. [Item 4] The LIDAR system according to item 3, wherein one or more optical components receive the LO signal from the LO input, but the LO signal at the LO input is less than 5 watts. [Item 5] First optical detector and, Further including a second optical detector, The one or more optical components mentioned above are: The first segmented LO signal and the first reflected beam are provided to the first photodetector so that the first photodetector generates a first electrical signal using the first segmented LO signal and the first reflected beam. The LIDAR system according to item 3, further configured to provide the second segmented LO signal and the second reflected beam to the second photodetector, causing the second photodetector to generate a second electrical signal from the second segmented LO signal and the second reflected beam. [Item 6] The LIDAR system described in item 5, wherein the crosstalk associated with the first electrical signal and the second electrical signal is -55 dB or less at 1 MHz and 200 MHz. [Item 7] The LiDAR system according to item 5, wherein the first light detector includes a pair of photodiodes, the pair of photodiodes having a CMRR (common mode rejection ratio) of 30 dB or more. [Item 8] The first optical detector is a LIDAR system according to item 5, having a bandwidth of 3 dB between 80 kHz and 650 MHz. [Item 9] The LiDAR system according to item 5, wherein the first light detector has a responsibility of 0.9 A / W (amperes per watt) or more, and the light beam has an operating wavelength that is the same as or substantially the same as 1550 nanometers. [Item 10] The LiDAR system according to item 5, further comprising a transimpedance amplifier (TIA) having a peak noise-equivalent power (NEP) of less than 5 × 10⁻¹² watts per square root Hertz, wherein the first light detector is configured to provide the first electrical signal to the TIA. [Item 11] The LiDAR system according to item 5, further comprising a TIA having a gain between 4 kΩ and 25 kΩ, wherein the first optical detector is configured to provide the first electrical signal to the TIA. [Item 12] The semiconductor substrate includes one or more optical components, the semiconductor substrate includes a plurality of outputs, each of which has a pitch between 31.75 micrometers and 381 micrometers, relating to the LIDAR system described in item 1. [Item 13] The LIDAR system according to 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 the steering system or braking system, A vehicle controller including one or more processors, wherein the one or more processors One or more optical components placed on a semiconductor substrate are configured to receive a light beam generated by a laser light source—the light beam being associated with the LO signal— The one or more optical components described above divide the optical beam into a first divided optical beam and a second divided optical beam, The one or more optical components transmit the first split optical beam and the second split optical beam to the optical device. The one or more optical components are configured to receive a first reflected beam associated with the first divided light beam and a second reflected beam associated with the second divided light beam from the optical device. The one or more optical components are configured to pair the first reflected beam with the LO signal and the second reflected beam with the 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] An autonomous vehicle control system including a LiDAR system as described in any one of items 1 through 13.

Claims

1. It is a LIDAR (light detection and ranging) system, A laser light source configured to generate an optical signal, Transceiver and, Equipped with, The aforementioned transceiver is Multiple transmit (TX) outputs through which the optical signal is transmitted to the environment, A light beam is received through multiple receiver (RX) inputs, Includes, The aforementioned transceiver is Receives one or more local oscillator (LO) signals, One or more optical signals received from the laser light source are transmitted to the environment via the plurality of TX outputs. The first return light and the second return light reflected from one or more objects in the environment are received via the plurality of RX inputs. The first return light and the first LO signal among the one or more LO signals are output to the first RX output. The second return light and the second LO signal from the one or more LO signals are output to the second RX output. It is configured in such a way, The plurality of TX outputs and the plurality of RX inputs are arranged on the first side of the transceiver in a LiDAR system.

2. The LIDAR system according to claim 1, wherein the plurality of TX outputs and the plurality of RX inputs are interleaved on the first side of the transceiver.

3. The LIDAR system according to claim 1, further comprising a first detector that outputs the first return light and the first LO signal.

4. The aforementioned transceiver is The first semiconductor substrate includes the aforementioned plurality of TX outputs, The second semiconductor substrate includes the aforementioned plurality of RX inputs, The LIDAR system according to claim 1, including the following:

5. The LIDAR system according to claim 4, wherein the first semiconductor substrate and the second semiconductor substrate are arranged at intervals corresponding to the pitch of the plurality of TX outputs or the pitch of the plurality of RX inputs.

6. The aforementioned transceiver is The one or more LO signals provided through them to the transceiver are connected to one or more LO inputs, One or more optical signals are provided through one or more TX inputs to the transceiver, The LIDAR system according to claim 1, including the following:

7. The LIDAR system according to claim 6, wherein the one or more LO inputs, the one or more TX inputs, and the first RX output are arranged on the second side of the transceiver.

8. The LIDAR system according to claim 1, further comprising a second detector that outputs the second return light and the second LO signal.

9. The LIDAR system according to claim 7, wherein the second RX output is located on the second side surface of the transceiver.

10. The LIDAR system according to claim 6, wherein the one or more LO inputs and the one or more TX inputs are located between the first RX output and the second RX output.

11. The LIDAR system according to claim 1, further comprising a scanner configured to receive one or more optical signals transmitted from the plurality of TX outputs through free space.

12. It is a LIDAR (light detection and ranging) system, A laser light source configured to generate an optical signal, Equipped with a transceiver, The aforementioned transceiver is Multiple transmit (TX) outputs through which the optical signal is transmitted to the environment, A light beam is received through multiple receiver (RX) inputs, Includes, The aforementioned transceiver is Receives one or more local oscillator (LO) signals, One or more optical signals received from the laser light source are transmitted to the environment via the plurality of TX outputs. The first return light and the second return light reflected from one or more objects in the environment are received via the plurality of RX inputs. The first return light and the first LO signal among the one or more LO signals are output to the first RX output. The second return light and the second LO signal from the one or more LO signals are output to the second RX output. It is configured in such a way, The plurality of TX outputs and the plurality of RX inputs are arranged on the first side of the transceiver, and are connected to a LIDAR system. One or more processors configured to control the operation of an autonomous vehicle using the first return light and the first LO signal, An autonomous vehicle control system equipped with the following features.

13. The autonomous vehicle control system according to claim 12, wherein the plurality of TX outputs and the plurality of RX inputs are interleaved on the first side of the transceiver.

14. The aforementioned transceiver is The first semiconductor substrate includes the aforementioned plurality of TX outputs, The second semiconductor substrate includes the aforementioned plurality of RX inputs, The autonomous vehicle control system according to claim 12, including the above.

15. The autonomous vehicle control system according to claim 14, wherein the first semiconductor substrate and the second semiconductor substrate are arranged at intervals corresponding to the pitch of the plurality of TX outputs or the pitch of the plurality of RX inputs.

16. The aforementioned transceiver is The one or more LO signals provided through them to the transceiver are connected to one or more LO inputs, One or more optical signals are provided through one or more TX inputs to the transceiver, The autonomous vehicle control system according to claim 12, including the above.

17. The aforementioned LIDAR system is A first detector from which the first return light and the first LO signal are output, A second detector from which the second return light and the second LO signal are output, The autonomous vehicle control system according to claim 12, further comprising the following:

18. The autonomous vehicle control system according to claim 16, wherein the one or more LO inputs and the one or more TX inputs are located between the first RX output and the second RX output.

19. The autonomous vehicle control system according to claim 16, wherein the one or more LO inputs, the one or more TX inputs, the plurality of first RX outputs, and the second RX outputs are arranged on the second side of the transceiver.

20. At least one of the steering system or braking system, It is a LIDAR (light detection and ranging) system, A laser light source configured to generate an optical signal, Transceiver and, Equipped with, The aforementioned transceiver is Multiple transmit (TX) outputs through which the optical signal is transmitted to the environment, A light beam is received through multiple receiver (RX) inputs, Includes, The aforementioned transceiver is Receives one or more local oscillator (LO) signals, One or more optical signals received from the laser light source are transmitted to the environment via the plurality of TX outputs. The first return light and the second return light reflected from one or more objects in the environment are received via the plurality of RX inputs. The first return light and the first LO signal among the one or more LO signals are output to the first RX output. The second return light and the second LO signal from the one or more LO signals are output to the second RX output. It is configured in such a way, The plurality of TX outputs and the plurality of RX inputs are arranged on the first side of the transceiver, and are connected to a LIDAR system. One or more processors configured to control the operation of at least one of the steering system or braking system using the first return light and the first LO signal, An autonomous vehicle equipped with the following features.

Images