Lidar system and multiple detection signal processing method thereof

Patent metadata

Field	Value
Publication number	US-2017234977-A1
Application number	US-201615232716-A
Country	US
Kind code	A1
Filing date	Aug 9, 2016
Priority date	Feb 17, 2016
Publication date	Aug 17, 2017
Grant date	—

Abstract

Disclosed are a lidar system and a multiple detection signal processing method thereof. A multiple detection signal processing method includes outputting a plurality of transmitted signals having different wavelengths into a space according to a preset time difference, receiving a plurality of received signals received by reflecting the plurality of transmitted signals from circumferential objects, and filtering, as interference/noise signals, received pulse signals that have not a preset threshold time interval with an arbitrary received signal among the plurality of receive signals.

First claim

What is claimed is:

1 . A multiple detection signal processing method comprising:
outputting a plurality of transmitted signals having different wavelengths into a space according to a preset time difference; receiving a plurality of received signals received by reflecting the plurality of transmitted signals from circumferential objects; and filtering, as interference/noise signals, received pulse signals that have not a preset threshold time interval with an arbitrary received signal among the plurality of receive signals.

2 . The multiple detection signal processing method of claim 1 , wherein the plurality of transmitted signals are output through the same path in the space.

3 . The multiple detection signal processing method of claim 1 , wherein the plurality of transmitted signals configured as a plurality of pulse signals having a preset pulse period.

4 . The multiple detection signal processing method of claim 1 , wherein the plurality o received signals have different wavelengths corresponding to the different wavelengths of the plurality of transmitted signals.

5 . The multiple detection signal processing method of claim 1 , further comprising setting an allowable error with respect to the time difference as the threshold time interval.

6 . The multiple detection signal processing method of claim 1 , further comprising:
setting, a maximum value of the time difference, a round trip time with respect to a maximum measurement distance of an arbitrary transmitted pulse signal among the plurality of transmitted signals; setting a measurable minimum time interval as a minimum value of the time difference; and setting, as the time difference, an arbitrary value between the maximum value and the minimum value.

7 . The multiple detection signal processing method of claim 6 , further comprising setting, as the threshold time interval, an allowable error with respect to the arbitrary value.

8 . The multiple detection signal processing method of claim 6 , further comprising:
dividing a space between the maximum value and the minimum value at the allowable error; and storing, in a time table set, N allowable errors formed in the dividing at N threshold time intervals.

9 . The multiple detection signal processing method of claim 8 , further comprising setting, as the threshold time interval, any one of the N threshold time intervals.

10 . The multiple detection signal processing method of claim 1 , further comprising selecting arbitrary wavelengths among a plurality of central wavelengths having a preset wavelength allowable width as the different wavelengths with respect to the plurality of transmitted signals.

11 . The multiple detection signal processing method of claim 1 , further comprising processing the plurality of filtered received signals, thereby outputting point cloud data on the circumferential objects.

12 . A multiple detection signal processing apparatus comprising:
a transmitting unit configured to output a plurality of transmitted signals having different wavelengths into a space according to a preset time difference; a receiving unit configured to receive a plurality of received signals received by reflecting the plurality of transmitted signals from circumferential objects; and a signal processing and control unit configured to filter, as interference/noise signals, received pulse signals that do not have a preset threshold time interval with an arbitrary received pulse signal among the plurality of received signals.

13 . The multiple detection signal processing apparatus of claim 12 , wherein the transmitting unit includes:
a plurality of transmitters each configured to output the plurality of transmitted signals; an optical coupler configured to couple the plurality of transmitted signals and output the plurality of transmitted signals through the same path; and a mirror scanner configured to output the plurality of transmitted signal output from optical coupler as an arbitrary point in the space.

14 . The multiple detection signal processing apparatus of claim 12 , wherein the receiving unit includes:
a lens configured to condense the plurality of received signals; a wavelength division multiplexer configured to divide the plurality of condensed received signals according to wavelengths; and a plurality of receivers configured to respectively receive the plurality of divided received signals.

15 . The multiple detection signal processing apparatus of claim 12 , wherein the signal processing and control unit sets, as the threshold time interval, an allowable error with respect to the time difference.

16 . The multiple detection signal processing apparatus of claim 12 , wherein the signal processing and control unit sets, a maximum value of the time difference, a round trip time with respect to a maximum measurement distance of an arbitrary transmitted pulse signal among the plurality of transmitted signals, sets a measurable minimum time interval as a minimum value of the time difference, and sets, as the time difference, an arbitrary value between the maximum value and the minimum value.

17 . The multiple detection signal processing apparatus of claim 16 , wherein the signal processing and control unit sets, as the threshold time interval, an allowable error with respect to the arbitrary value.

18 . The multiple detection signal processing apparatus of claim 16 , wherein the signal processing and control unit divides a space between the maximum value and the minimum value at the allowable error, and stores, in a time table set, N allowable errors formed in the dividing at N threshold time intervals.

19 . The multiple detection signal processing apparatus of claim 18 , wherein the signal processing and control unit sets, as the threshold time interval, any one of the N threshold time intervals.

20 . The multiple detection signal processing apparatus of claim 12 , wherein the signal processing and control unit selects arbitrary wavelengths among a plurality of central wavelengths having a preset wavelength allowable width as the different wavelengths with respect to the plurality of transmitted signals.

Assignees

• Electronics & Telecommunications Res Inst

Inventors

• Kim Jong Deog

Classifications

• G01S7/4876 Primary

  by removing unwanted signals (G01S7/495 takes precedence) · CPC title

• G01S17/894

  Three-dimensional [3D] imaging with simultaneous measurement of time-of-flight at a two-dimensional [2D] array of receiver pixels, e.g. time-of-flight cameras or flash lidar · CPC title

• G01S17/42 Primary

  Simultaneous measurement of distance and other co-ordinates (indirect measurement G01S17/46) · CPC title

• G01S17/10

  using transmission of interrupted, pulse-modulated waves (determination of distance by phase measurements G01S17/32) · CPC title

• G01S7/4815

  using multiple transmitters · CPC title