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US 11,899,116 B2Granted
Single beam digitally modulated lidar for autonomous vehicle distance sensing
AssigneeNuro, Inc.
InventorsRussell Smith, Hao Li
Life of this patent
Estimating the term…
Abstract
According to one aspect, a relatively low-cost sensor for use on an autonomous vehicle is capable of detecting moving objects in a range or a zone that is between approximately 80 meters and approximately 300 meters away from the autonomous vehicle. A substantially single fan-shaped light beam is scanned for a full 360 degrees in azimuth. Using frequency-modulated-continuous-wave (FMCW) or phase coded modulation on the beam, with back end digital signal processing (DSP), moving objects may effectively be distinguished from a substantially stationary background.
Claims24
A method for performing lidar sensing, comprising:
- generating a single divergent light beam from a stable light source to which baseband modulation is applied to produce a modulated light beam;
- scanning the modulated light beam in an azimuth direction into a target area;
- receiving returned light from the target area with an optical receiver coupled to the stable light source;
- and
- demodulating the returned light with a baseband demodulator and applying coherent detection based on returned light from the target area to detect one or more objects in the target area.
2 more elements
A lidar sensor system comprising:
- a stable light source configured to produce a light beam that is substantially continuous;
- a baseband modulator configured to generate a baseband modulation;
- an optical transmitter coupled to the baseband modulator and comprising a mixer coupled to an output of the baseband modulator and to the stable light source, the mixer configured to apply the baseband modulation to the light beam and to produce a modulated light beam for transmission into a target area;
- an optical receiver coupled to the stable light source and configured to receive returned light from the target area, wherein the optical receiver includes a mixer coupled to the stable light source configured to mix the returned light with the light beam output by the stable light source;
- and
- a baseband demodulator coupled to the optical receiver and configured to demodulate the returned light to detect one or more objects in the target area.
3 more elements
A lidar sensor system comprising:
- a stable light source configured to produce a light beam that is substantially continuous;
- a baseband modulator configured to generate a baseband modulation;
- an optical transmitter coupled to the baseband modulator and configured to apply the baseband modulation to the light beam from the stable light source to produce a modulated light beam, wherein the optical transmitter includes a divergent beam generator configured to receive the modulated light beam to generate a single divergent light beam, wherein the optical transmitter includes a first mixer coupled to an output of the baseband modulator and to the stable light source, the first mixer configured to apply the baseband modulation to the light beam;
- a beam steering mechanism configured to scan the single divergent light beam in an azimuth direction into a target area;
- an optical receiver coupled to the stable light source and configured to receive returned light from the target area, wherein the optical receiver includes a first mixer coupled to the stable light source and configured to mix the returned light with the light beam output by the stable light source to produce mixed light output;
- and
- a baseband demodulator coupled to the optical receiver and configured to demodulate the mixed light output to enable detection of one or more objects in the target area.
4 more elements
A lidar sensor system comprising:
- a stable light source configured to produce a light beam that is substantially continuous;
- a baseband modulator configured to generate a baseband modulation;
- an optical transmitter coupled to the baseband modulator and configured to apply the baseband modulation to the light beam, wherein the optical transmitter includes:
- a phase shifter coupled to receive the light beam from the stable light source and configured to phase shift the light beam by approximately 90 degrees to produce a phase shifted light beam;
- a first mixer coupled to the stable light source and to an output of the baseband modulator, the first mixer configured to apply the baseband modulation to the light beam from the stable light source to produce a first modulated light beam;
- a second mixer coupled to an output of the baseband modulator and to an output of the phase shifter, the second mixer configured to apply the baseband modulation to the phase shifted light beam to produce a second modulated light beam;
- and
- an optical combiner configured to combine the first modulated light beam and the second modulated light beam to produce a modulated transmit light beam for transmission into a target area;
- an optical receiver coupled to the stable light source and configured to receive returned light from the target area;
- and
- a baseband demodulator coupled to the optical receiver and configured to demodulate the returned light to detect one or more objects in the target area.
8 more elements
A lidar sensor system comprising:
- a stable light source configured to produce a light beam that is substantially continuous;
- a baseband modulator configured to generate a baseband modulation;
- an optical transmitter coupled to the baseband modulator and configured to apply the baseband modulation to the light beam and to produce a modulated light beam for transmission into a target area;
- an optical receiver coupled to the stable light source and configured to receive returned light from the target area;
- and
- a baseband demodulator coupled to the optical receiver and configured to demodulate the returned light to detect one or more objects in the target area;
- wherein the optical receiver includes:
- a phase shifter coupled to receive the light beam from the stable light source and configured to phase shift the light beam by approximately 90 degrees to produce a phase shifted light beam;
- a first mixer coupled to receive the light beam from the stable light source and the returned light, the first mixer configured to mix the returned light with the light beam to produce a first returned light beam;
- and
- a second mixer coupled to receive the phase shifted light beam and the returned light, the second mixer configured to mix the returned light with the phase shifted light beam to produce a second returned light beam;
- wherein the baseband demodulator is configured to receive as input the first returned light beam and the second returned light beam.
9 more elements
Dependencies are inferred from the claim text.