Techniques for signal processing in a lidar system with multiple return waveguides

Abstract

A LIDAR system includes multiple waveguides to receive a return signal at different angles from a scanning mirror, multiple optical detectors to receive the return signal the plurality of waveguides, and a signal processing system operatively coupled to the plurality of optical detectors. The signal processing system is to process a signal generated from each of the optical detectors and combine the processed signals from the different optical detectors into a combined signal, wherein the combined signal is used to determine range and velocity information associated with a target.

What is claimed is: 
     
         1 . A light detection and ranging (LIDAR) system, comprising:
 a plurality of waveguides to receive a return signal at different angles from a scanning mirror;   a plurality of optical detectors to receive the return signal the plurality of waveguides; and   a signal processing system operatively coupled to the plurality of optical detectors to:
 process a signal generated from each optical detector of the plurality of optical detectors; and 
 combine the processed signals from the plurality of optical detectors into a combined signal, wherein the combined signal is used to determine range and velocity information associated with a target. 
   
     
     
         2 . The LIDAR system of  claim 1 , wherein a local oscillator signal is combined with the return signal at the plurality of optical detectors to produce a beat frequency used to calculate the range and velocity information of the target. 
     
     
         3 . The LIDAR system of  claim 1 , wherein the signal processing system comprises:
 an amplifier associated with each of the optical detectors to amplify the signal generated by each of the optical detectors; and   a filtering component associated with each of the optical detectors to filter frequencies outside a range of frequencies associated with the corresponding optical detector and waveguide.   
     
     
         4 . The LIDAR system of  claim 3 , wherein the filtering component associated with each of the optical detectors comprises a band-pass filter corresponding to frequencies associated with a position of the optical detector and corresponding waveguide. 
     
     
         5 . The LIDAR system of  claim 1 , wherein the signal processing system comprises:
 an analog to digital converter associated with each of the optical detectors, wherein each analog to digital converter is to convert a band of frequencies associated with a position of the optical detector and corresponding waveguide.   
     
     
         6 . The LIDAR system of  claim 1 , wherein the signal processing system is to:
 combine the signal generated from a plurality of subsets of the optical detectors into a plurality of intermediate combined signals;   process the plurality of intermediate combined signals; and   combine the plurality of intermediate combined signals into the combined signal.   
     
     
         7 . The LIDAR system of  claim 1 , wherein a local oscillator signal is distributed across the plurality of optical detectors, wherein a power level of the local oscillator signal provided to each of the plurality of optical detectors that is associated with a position of the corresponding waveguide. 
     
     
         8 . A light detection and ranging (LIDAR) apparatus, comprising:
 a plurality of waveguides to receive a return signal at different angles from a scanning mirror;   a plurality of optical detectors to receive the return signal the plurality of waveguides; and   circuitry, operatively coupled to the plurality of optical detectors, to:
 process a signal generated from each photodetector of the plurality of optical detectors; and 
 combine the processed signals from the plurality of optical detectors into a combined signal, wherein the combined signal is used to determine range and velocity information associated with a target. 
   
     
     
         9 . The LIDAR apparatus of  claim 8 , wherein a local oscillator signal is combined with the return signal at the plurality of optical detectors to produce a beat frequency to calculate the range and velocity information associated with a target. 
     
     
         10 . The LIDAR apparatus of  claim 8 , wherein the signal processing system comprises:
 an amplifier associated with each of the optical detectors to amplify the signal generated by each of the optical detectors; and   a filtering component associated with each of the optical detectors to filter frequencies outside a range of frequencies associated with the corresponding optical detector and waveguide.   
     
     
         11 . The LIDAR apparatus of  claim 10 , wherein the filtering component associated with each of the optical detectors comprises a band-pass filter corresponding to frequencies associated with a position of the optical detector and corresponding waveguide. 
     
     
         12 . The LIDAR apparatus of  claim 8 , wherein the signal processing system comprises:
 an analog to digital converter associated with each of the optical detectors, wherein each analog to digital converter is to convert a band of frequencies associated with a position of the optical detector and corresponding waveguide.   
     
     
         13 . The LIDAR apparatus of  claim 8 , wherein the signal processing system is to:
 combine the return signal from a plurality of subsets of the optical detectors into a plurality of intermediate combined signal;   process the plurality of intermediate combined signals; and   combine the plurality of intermediate combined signals into the combined signal.   
     
     
         14 . The LIDAR apparatus of  claim 8 , wherein a local oscillator signal is distributed across the plurality of optical detectors, wherein a power level of the local oscillator signal provided to each of the plurality of optical detectors that is associated with a position of the corresponding waveguide. 
     
     
         15 . A method of operating a light detection and ranging (LIDAR) system, comprising:
 receiving, at a plurality of waveguides, a return signal at different angles from a scanning mirror;   generating an electrical signal at a plurality of optical detectors based on the return signal from the plurality of waveguides;   processing the electrical signal generated from each photodetector of the plurality of optical detectors; and   combining the processed signals from the plurality of optical detectors into a combined signal, wherein the combined signal is used to determine range and velocity information associated with a target.   
     
     
         16 . The method of  claim 15 , further comprising:
 combining a local oscillator signal with the return signal at the plurality of optical detectors to produce a beat frequency to calculate the range and velocity information associated with a target.   
     
     
         17 . The method of  claim 15 , further comprising
 amplifying the signal generated by each of the optical detectors; and   filtering the signal generated by each of the optical detectors.   
     
     
         18 . The method of  claim 15 , wherein the LIDAR system is a frequency modulated continuous wave (FMCW) LIDAR system. 
     
     
         19 . The method of  claim 15 , further comprising:
 converting, by an analog to digital converter associated with each optical detector, the signal from each of the optical detectors from an analog signal to a digital signal, wherein each analog to digital converter is to convert a band of frequencies associated with a position of the optical detector and corresponding waveguide.   
     
     
         20 . The method of  claim 15 , further comprising:
 combining the return signal from a plurality of subsets of the optical detectors into a plurality of intermediate combined signal;   processing the plurality of intermediate combined signals; and   combining the plurality of intermediate combined signals into the combined signal.