Sensor device

Patent metadata

Field	Value
Publication number	US-12044807-B2
Application number	US-201916962326-A
Country	US
Kind code	B2
Filing date	Jan 15, 2019
Priority date	Jan 16, 2018
Publication date	Jul 23, 2024
Grant date	Jul 23, 2024

Abstract

A sensor device for determining a distance and/or speed of an object, including a transmitting unit for emitting light of at least one frequency onto the object, the transmitting unit being designed for emitting light in at least one angular range, the light in the angular range being time-dependent varied essentially simultaneously with frequencies in different frequency ranges, a receiving unit for receiving light reflected by the object, the receiving unit being designed for scanning the received light in the particular frequency range at least two points in time, and an evaluation unit, which is designed for determining the distance and/or the speed of the object on the basis of the emitted light and the points in time at which the received light was scanned.

First claim

What is claimed is:

1. A sensor device for determining a distance and/or speed of an object, comprising:
a transmitting unit configured to:
generate light; and
in a single frequency ramp period over time:
produce from the light a plurality of light components that each has a respective frequency ramp with which respective frequencies of the respective light component change at a rate over the time of the ramp period from a respective starting frequency of the respective ramp at a start time of the ramp period to a respective ending frequency of the respective ramp at an end time of the ramp period, wherein:
the rate is the same for different ones of the plurality of light components so that, for each pair of the plurality of light components, a respective offset between the frequencies of the respective pair is constant throughout the ramp period; and
the respective starting frequencies of the plurality of light components all differ from one another so that respective frequency ranges of the plurality of light components all differ from one another; and

simultaneously emit the plurality of light components onto the object in at least one angular range;

a receiving unit configured to receive light reflected by the object, the receiving unit being configured to scan the received light in a particular frequency range at least two points in time; and
an evaluation unit configured to determine the distance and/or the speed of the object based on the emitted light and the points in time at which the received light was scanned.

2. The sensor device as recited in claim 1 , wherein the transmitting unit is configured to linearly vary the frequency in the angular range.

3. The sensor device as recited in claim 2 , wherein the rate is constant so that the frequencies of each of the light components change linearly over the ramp period.

4. The sensor device as recited in claim 1 , wherein the transmitting unit includes a light source and a modulation unit configured to vary the frequencies of the light components.

5. The sensor device as recited in claim 4 , wherein the modulation unit includes a respective modulator for each of the light components, the modulation unit being an acousto-optical modulator.

6. The sensor device as recited in claim 1 , wherein the at least one angular range includes a plurality of angular ranges, and the transmitting unit includes a scanning unit configured to emit the light components into different ones of the plurality of angular ranges.

7. The sensor device as recited in claim 1 , wherein the respective frequency range of the respective ramp of one of the light components overlaps with the respective frequency range of the respective ramp of another of the light components.

8. The sensor device as recited in claim 1 , wherein the transmitting unit includes:
a plurality of modulators; and
a single light source by which the light is generated, the generated light being supplied to the plurality of modulators for the production of the plurality of light components, with each of the plurality of modulators producing a respective one of the plurality of light components from the light generated by the single light source.

9. A method for determining a distance and/or speed of an object, comprising the following steps:
in a single frequency ramp period:
using a transmitting unit to simultaneously emit, in at least one angular range and onto an object, a plurality of light components, respective frequencies of each of which are varied over the ramp period so that each of the light components has a respective frequency range, the respective frequency ranges differing from one another;
receiving light reflected by the object using a receiving unit; and
scanning the received light in a particular frequency range at at least two points in time; and

determining the distance and/or speed of the object based on the emitted light and the points in time at which the received light was scanned.

10. The method as recited in claim 9 , wherein the points in time at which scanning is carried out are selected having a same temporal distance.

11. The method as recited in claim 9 , wherein the determination of the distance and/or the speed of the object takes place based on a two-dimensional Fourier transform and a frequency estimation.

12. The method as recited in claim 11 , wherein the points in time at which the scanning is carried out are selected having a non-equidistant temporal distance and/or frequency spacings between at least two frequency ranges are selected to be different, and the frequency estimation takes place using a compressed sensing method taking into consideration a distance-induced frequency component in a Doppler frequency.

13. A method for determining a distance and/or speed of an object, the method comprising:
generating light;
in a single frequency ramp period over time:
producing from the light a plurality of light components that each has a respective frequency ramp with which respective frequencies of the respective light component change at a rate over the time of the ramp period from a respective starting frequency of the respective ramp at a start time of the ramp period to a respective ending frequency of the respective ramp at an end time of the ramp period, wherein:
the rate is the same for different ones of the plurality of light components so that, for each pair of the plurality of light components, a respective offset between the frequencies of the respective pair is constant throughout the ramp period; and
the respective starting frequencies of the plurality of light components all differ from one another so that respective frequency ranges of the plurality of light components all differ from one another; and

simultaneously emitting the plurality of light components onto the object in at least one angular range;

receiving light reflected by the object by scanning the received light in a particular frequency range at least two points in time; and
determining the distance and/or the speed of the object based on the emitted light and the points in time at which the received light was scanned.

Assignees

• Bosch Gmbh Robert

Inventors

• Brosche Thomas
• Kern Oliver

Classifications

• G01S17/003

  Bistatic lidar systems; Multistatic lidar systems · CPC title

• G01S7/4917

  superposing optical signals in a photodetector, e.g. optical heterodyne detection · CPC title

• G01S7/4817

  relating to scanning · CPC title

• G01S17/34

  using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal · CPC title

• G01S17/58

  Velocity or trajectory determination systems; Sense-of-movement determination systems · CPC title