Light detection and ranging system

Patent metadata

Field	Value
Publication number	US-10969651-B2
Application number	US-201815876544-A
Country	US
Kind code	B2
Filing date	Jan 22, 2018
Priority date	Jan 25, 2017
Publication date	Apr 6, 2021
Grant date	Apr 6, 2021

Abstract

A multi-channel light detection and ranging system includes a plurality of active channels, each comprising a photosensitive element arranged to be exposed to light and an analog front end circuit arranged for receiving a signal from the photosensitive element. A compensation channel comprises a compensation element and an analog front end circuit arranged for receiving signals from the compensation capacitor. A processing unit arranged for receiving signals from the active channels and the compensation channel, deriving at a compensation signal from the signal received from the compensation channel, and compensating for the crosstalk interference and/or the interference common to the analog front end circuits of the active channels, using the compensation signal.

First claim

The invention claimed is:

1. A multi-channel light detection and ranging system comprising:
a plurality of active channels, each comprising a photosensitive element arranged to be exposed to light and an analog front end circuit arranged for receiving a signal from said photosensitive element representative of the light, whereby at least one of said active channels is susceptible of being affected by crosstalk interference caused by inductive, resistive or capacitive coupling with at least one other active channel and/or by interference common to said analog front end circuits,
at least one compensation channel also susceptible of being affected by said crosstalk interference caused by inductive, resistive or capacitive coupling with at least one active channel, said at least one compensation channel comprising a compensation element being substantially insensitive to light and an analog front end circuit arranged for receiving signals from said compensation element, said compensation element being electrically connected to a network shared by said photosensitive elements and to said analog front end circuit of said at least one compensation channel,
a processing unit arranged for
receiving signals from said active channels and said at least one compensation channel,
deriving at least one compensation signal from said signal received from said at least one compensation channel, and
compensating for said crosstalk interference and/or said interference common to said analog front end circuits of said active channels;
wherein compensating for said crosstalk comprises one or more of:
subtracting said at least one compensation signal from said signals received from said active channels,
modifying said signal received from said photosensitive element, said modifying comprising at least a pulse shaping,
performing a gradient compensation wherein a weighted sum of signals is determined whereby the position of two of said compensation channels is taken into account.

2. The multi-channel light detection and ranging system as in claim 1 , wherein said compensation element is implemented as a blinded photodiode.

3. The multi-channel light detection and ranging system as in claim 1 , wherein said compensation element is implemented as capacitor.

4. The multi-channel light detection and ranging system as in claim 1 , wherein said compensating for said crosstalk comprises said subtracting said at least one compensation signal from said signals received from said active channels.

5. The multi-channel light detection and ranging system as in claim 1 , wherein said compensating for said crosstalk comprises said modifying said signal received from said photosensitive element, said modifying comprising at least the pulse shaping.

6. The multi-channel light detection and ranging system as in claim 5 , wherein said modifying comprises performing a scaling and/or applying said signal received from said photosensitive element to a filter.

7. The multi-channel light detection and ranging system as in claim 1 , comprising at least two compensation channels.

8. The multi-channel light detection and ranging system as in claim 7 , wherein said compensating comprises said performing the gradient compensation wherein the weighted sum of signals is determined whereby the position of the two of said compensation channels is taken into account.

9. The multi-channel light detection and ranging system as in claim 1 , whereby said photosensitive elements in said plurality of active channels have a terminal in common.

10. The multi-channel light detection and ranging system as in claim 1 , wherein said processing unit is on a same substrate as said photosensitive elements and said analog front end circuits of said plurality of said active channels.

11. The multi-channel light detection and ranging system as in claim 1 , wherein said photosensitive elements of said plurality of channels are on a different substrate than said analog front end circuits and said processing unit.

12. The multi-channel light detection and ranging system as in claim 1 , wherein said photosensitive elements of said active channels are on a different substrate than said compensation element of said at least one compensation channel.

13. The multi-channel light detection and ranging system as in claim 1 , wherein said processing unit is arranged for detecting a signal chain failure by observing a signal obtained after crosstalk interference compensation.

14. The multi-channel light detection and ranging system as in claim 1 , further arranged for generating at a given time an interference signal, common to said analog front end circuits, and whereby said processing unit is arranged for detecting a signal chain failure by observing at said given time a signal obtained after crosstalk interference compensation.

Assignees

• Melexis Technologies Nv

Inventors

• Seliuchenko Volodymyr
• Mizuki Marcelo

Classifications

• G01S7/497

  Means for monitoring or calibrating · CPC title

• G01S7/4863 Primary

  Detector arrays, e.g. charge-transfer gates · CPC title

• G01S7/4861 Primary

  Circuits for detection, sampling, integration or read-out · CPC title

• G01S17/42

  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