LIDAR arrangement and LIDAR method

Patent metadata

Field	Value
Publication number	US-11194024-B2
Application number	US-201816034113-A
Country	US
Kind code	B2
Filing date	Jul 12, 2018
Priority date	Jul 12, 2017
Publication date	Dec 7, 2021
Grant date	Dec 7, 2021

Abstract

A LIDAR arrangement comprising a laser transmitter for transmitting pulses of a laser radiation to a measurement object, and a receiver for receiving pulses of the laser radiation backscattered from the measurement object, wherein the laser transmitter is configured to transmit a pulse sequence in which successive pulses respectively comprise a particular optical frequency shift to each other and wherein the receiver either includes a dispersive element for separating the pulses in time depending on the optical frequency by a frequency-based deflection, and a position resolution optical matrix transmitter on which the pulses separated in time by the dispersive element are mapped, or includes a frequency analyzer for the frequency-based separation of the pulses by superimposition with a reference radiation.

First claim

The invention claimed is:

1. A LIDAR arrangement configured for atmospheric measurements, comprising:
a laser transmitter for transmitting individual pulses of a laser radiation to a measurement object, and
a receiver for receiving the individual pulses of the laser radiation backscattered from the measurement object,
wherein the laser transmitter is configured to transmit a pulse series in which successive pulses respectively comprise an optical frequency shift to each other, and
wherein the receiver
includes a dispersive element for spatially separating the pulses depending on the optical frequency by a frequency-dependent deflection, and a matrix sensor on which the pulses spatially separated by the dispersive element are mapped, and, between the dispersive element and the matrix sensor, the receiver comprises an interferometer configured for mapping at least partially spatially separated interferograms to the individual pulses of the pulse sequence on the matrix sensor.

2. The LIDAR arrangement according to claim 1 , wherein the laser transmitter is configured to transmit pulses with a pulse frequency of 1 kHz to 1 MHz.

3. The LIDAR arrangement according to claim 1 , wherein the laser transmitter, at least one of
includes a master oscillator including a plurality of lasers, a master laser that is directly modulatable in its wave length, or a combination of a master laser and a downstream modulator for modulating a wave length of the master laser,
includes at least one of at least one fiber laser and several optical amplifiers for amplifying a signal of the master oscillator, wherein the several optical amplifiers are selected from a group consisting of fiber lasers, fiber pre-amplifiers and fiber post-amplifiers,
includes a frequency multiplier downstream of the amplifier or of the fiber laser,
includes a transmission telescope, and
includes a scanner for scanning an angular range with radiation from the laser transmitter.

4. The LIDAR arrangement according to claim 1 , wherein at least one of
the dispersive element includes one or more elements from the group consisting of a grating, a prism, a Fabry-Pérot interferometer, a fiber-optical de-multiplexer, a reconfigurable fiber-optical multiplexer, and an arrayed waveguide grating,
the matrix sensor is chosen from the group consisting of a one-dimensional matrix sensor, a two-dimensional matrix sensor, a photo detector array, a one-dimensional photo detector array, a two-dimensional photo detector array, a CCD array, a one-dimensional CCD array, a two-dimensional CCD array, a PIN detector array, a one-dimensional PIN detector array, a two-dimensional PIN detector array, a CMOS array, a one-dimensional CMOS array, a two-dimensional CMOS array, a CMOS APD array, a one-dimensional CMOS APD array, a two-dimensional CMOS APD array, an ICCD detector, a one-dimensional ICCD detector, a two-dimensional ICCD detector, an EMCCD array, a one-dimensional EMCCD array, a two-dimensional EMCCD array, an IBCCD array, a one-dimensional IBCCD array, a two-dimensional IBCCD array, an EMCMOS array, a one-dimensional EMCMOS array, a two-dimensional EMCMOS array, an IBCMOS array, a one-dimensional IBCMOS array, and a two-dimensional IBCMOS array, and
the frequency analyzer comprises a photo detector and a device for the superimposition of received radiation with a reference radiation on the photo detector, wherein the photo detector is configured for outputting a signal having a differential frequency corresponding to a difference between the frequencies of received radiation and a reference radiation.

5. The LIDAR arrangement according to claim 1 , wherein at least one of
the receiver comprises an interferometer for recording the spatially separated signal at least one of at different positions and under different angles, so that at an output of the interferometer at least partially separated interferograms to the individual separated frequency-shifted pulses are created which can be recorded by means of a one or two-dimensional photo detector array,
the receiver is a Fabry-Pérot interferometer or a Fizeau interferometer for recording the spatially divided signal and for producing at least partially spatially separated interferograms to the individual pulses, and
a coupling device for coupling the spatially separated pulses into the dispersive element in an arrangement of a line, a circle or any other two-dimensional arrangement of light rays.

6. The LIDAR arrangement according to claim 1 , wherein the receiver comprises at least one of
an A/D converter for the conversion of signals from pixels of the matrix sensor, and
an intermediate register for storing signals from pixels of the matrix sensor.

7. The LIDAR arrangement according to claim 1 , wherein the receiver comprises at least one of
a receive telescope, and
a light guide device for receiving radiation from different directions from the measurement object and for introduction into the dispersive element from different directions in different angles or at spatially displaced locations.

8. The LIDAR arrangement according to claim 1 , wherein the laser transmitter includes
a master oscillator selected from a group consisting of a master oscillator including a plurality of lasers, a plurality of diode lasers of different wave length, a master laser that is directly modulatable in its wave length, a combination of a master laser and a downstream modulator for modulating a wave length of the master laser,
at least one of at least one fiber laser and several optical amplifiers for amplifying a signal of the master oscillator, wherein the several optical amplifiers are selected from a group consisting of fiber lasers, fiber pre-amplifiers and fiber post-amplifiers,
a frequency multiplier downstream of the amplifier or of the fiber laser,
a transmission telescope, and
a scanner for scanning an angular range with a radiation from the laser transmitter.

9. The LIDAR arrangement according to claim 1 , wherein
the dispersive element includes one or more elements from the group consisting of a grating, a prism, a Fabry-Pérot interferometer, a fiber-optical de-multiplexer, a reconfigurable fiber-optical multiplexer, and an arrayed waveguide grating,
the matrix sensor is chosen from the group consisting of a one-dimensional matrix sensor, a two-dimensional matrix sensor, a photo detector array, a one-dimensional photo detector array, a two-dimensional photo detector array, a CCD array, a one-dimensional CCD array, a two-dimensional CCD array, a PIN detector array, a one-dimensional PIN detector array, a two-dimensional PIN detector array, a CMOS array, a one-dimensional CMOS array, a two-dimensional CMOS array, a CMOS APD array, a one-dimensional CMOS APD array, a two-dimensional CMOS APD array, an ICCD detector, a one-dimensional ICCD detector, a two-dimensional ICCD detector, an EMCCD array, a one-dimensional EMCCD array, a two-dimensional EMCCD array, an IBCCD array, a one-dimensional IBCCD array, a two-dimensional IBCCD array, an EMCMOS array, a one-dimensional EMCMOS array, a two-dimensional EMCMOS array, an IBCMOS array, a one-dimensional IBCMOS array, and a two-dimensional IBCMOS array, and
the frequency analyzer comprises a photo detector and a device for the superimposition of the received radiation with a reference radiation on the photo detector, wherein the photo detector is configured for outputting a signal having a differential frequency corresponding to a difference between the frequencies of received radiation and a reference radiation.

10. The LIDAR arrangement according to claim 1 , wherein
the receiver comprises an interferometer for recording the spatially separated signal at least one of a

Assignees

• Airbus Defence & Space Gmbh

Inventors

• Schmitt Nikolaus
• Halldorsson Thorsteinn

Classifications

• G01S7/4816

  of receivers alone · CPC title

• G01S17/26

  wherein the transmitted pulses use a frequency-modulated or phase-modulated carrier wave, e.g. for pulse compression of received signals · CPC title

• G01S7/4817

  relating to scanning · CPC title

• G01S7/486

  Receivers · CPC title

• G01S17/58

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