Systems and methods for noise reductions in Lidar sensing of a target by wavelength toggling and filtering

1. A method of mitigating backscatter noise in a Lidar system, the method comprising:

transmitting a first set of one or more pulses of a first wavelength from a laser emitter toward a target;

transmitting a second set of one or more pulses of a second wavelength from the laser emitter toward the target;

estimating, based on a first estimated distance of the target, a first time range for the first set of one or more pulses of the first wavelength to be received;

separating, with a first wavelength filter switch, received light into light of the first wavelength and light of the second wavelength;

during the first time range, generating a second estimated distance of the target based on the separated received light of the first wavelength; and

using the second estimated distance of the target to update the first estimated distance of the target.

2. The method of claim 1 , wherein the first and second sets of one or more pulses are transmitted from the laser emitter through a second wavelength filter switch.

3. The method of claim 1 , wherein the first and second sets of one or more pulses are transmitted for a first and second period of time, respectively, based on the first estimated distance of the target.

4. The method of claim 1 , wherein separating the received light comprises:

separating a backscattered signal of a third wavelength, wherein the third wavelength differs from the first wavelength; and

filtering out the backscattered signal.

5. The method of claim 4 wherein the third wavelength is the same as or similar to the second wavelength.

6. The method of claim 1 , wherein the first wavelength filter switch is a dichroic filter switch.

7. The method of claim 1 , wherein the first wavelength filter switch comprises a spectral-spatial filter.

8. The method of claim 1 , further comprising using the second estimated distance of the target to update a frequency of which pulses of the first wavelength and pulses of the second wavelength are transmitted toward the target.

9. The method of claim 1 , further comprising:

estimating, based on the first estimated distance of the target, a second time range for the second set of one or more pulses of the second wavelength to be received;

during the second time range, generating a third estimated distance of the target based on the separated received light of the second wavelength; and

using the third estimated distance of the target to update the first estimated distance of the target.

10. A Lidar system, comprising:

a laser emitter transmitting a first set of one or more pulses of a first wavelength and a second set of one or more pulses of a second wavelength toward a target;

a processor estimating, based on a first estimated distance of the target, a first time range for the first set of one or more pulses of the first wavelength to be received;

a variable waveplate or other filter receiving light;

a first wavelength filter switch separating the received light into light of the first wavelength and light of the second wavelength; and

the processor:

during the first time range, generating a second estimated distance of the target based on the separated received light of the first wavelength; and

using the second estimated distance of the target to update the first estimated distance of the target.

11. The Lidar system of claim 10 , wherein the first and second sets of one or more pulses are transmitted from the laser emitter through a second wavelength filter switch.

12. The Lidar system of claim 10 , wherein the first and second sets of one or more pulses are transmitted for a first and second period of time, respectively, based on the first estimated distance of the target.

13. The Lidar system of claim 10 , wherein separating the received light comprises:

separating a backscattered signal of a third wavelength, wherein the third wavelength differs from the first wavelength; and

filtering out the backscattered signal.

14. The Lidar system of claim 13 , wherein the third wavelength is the same as or similar to the second wavelength.

15. The Lidar system of claim 10 , wherein the first wavelength filter switch is a dichroic filter switch.

16. The Lidar system of claim 10 , wherein the first wavelength filter switch comprises a spectral-spatial filter switch.

17. A computing system, comprising:

a laser emitter transmitting a first set of one or more pulses of a first wavelength and a second set of one or more pulses of a second wavelength toward a target;

a processor estimating, based on a first estimated distance of the target, a first time range for the first set of one or more pulses of the first wavelength to be received;

a variable waveplate or other filter receiving light;

a first wavelength filter switch separating the received light into light of the first wavelength and light of the second wavelength; and

the processor:

during the first time range, generating a second estimated distance of the target based on the separated received light of the first wavelength; and

using the second estimated distance of the target to update the first estimated distance of the target.

18. The computing system of claim 17 , wherein the first and second sets of one or more pulses are transmitted from the laser emitter through a second wavelength filter switch.

19. The computing system of claim 17 , wherein the first and second sets of one or more pulses are transmitted for a first and second period of time, respectively, based on the first estimated distance of the target.

20. The computing system of claim 17 , wherein separating the received light comprises:

separating a backscattered signal of a third wavelength, wherein the third wavelength differs from the first wavelength; and

filtering out the backscattered signal.

21. The computing system of claim 20 , wherein the third wavelength is the same as or similar to the second wavelength.

22. The computing system of claim 17 , wherein the first wavelength filter switch is a dichroic filter switch.