Distributed Radar Signal Processing in a Radar System

• US 20160018511A1
• Filed: 02/27/2015
• Published: 01/21/2016
• Est. Priority Date: 07/17/2014
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Nayyar, Jasbir Singh, Ginsburg, Brian Paul, Ali, Murtaza, Bose, Sudipto
• Granted Patent: US 10,627,480 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01S 13/343 using sawtooth modulation
• CPC Class Codes: G01S 13/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S13/46
• CPC Class Codes: G01S 13/87 Combinations of radar systems, e.g. primary radar and secondary radar
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations
• CPC Class Codes: G01S 7/03 Details of HF subsystems specially adapted therefor, e.g. common to transmitter and receiver
• CPC Class Codes: G01S 7/352 Receivers
• CPC Class Codes: G01S 7/356 involving particularities of FFT processing

Abstract

A cascaded radar system is provided that includes a first radar system-on-a-chip (SOC) operable to perform an initial portion of signal processing for object detection on digital beat signals generated by multiple receive channels of the radar SOC, a second radar SOC operable to perform the initial portion of signal processing for object detection on digital beat signals generated by multiple receive channels in the radar SOC, and a processing unit coupled to the first radar SOC and the second radar SOC to receive results of the initial portion of signal processing from each radar SOC, the processing unit operable to perform a remaining portion of the signal processing for object detection using these results.

Claims

1. A cascaded radar system comprising:

a first radar system-on-a-chip (SOC) including a first plurality of receive channels and a first signal processor component coupled to the first plurality of receive channels to perform a first initial portion of signal processing for object detection on digital beat signals generated by the first plurality of receive channels;

a second radar SOC including a second plurality of receive channels and a second signal processor component coupled to the second plurality of receive channels to perform a second initial portion of signal processing for object detection on digital beat signals generated by the second plurality of receive channels; and

a processing unit coupled to the first radar SOC and the second radar SOC to receive first results of the first initial portion of signal processing and second results of the second initial portion of signal, the processing unit operable to perform a remaining portion of the signal processing for object detection using the first results and the second results.

2. The cascaded radar system of claim 1, in which the first initial portion of signal processing includes computing range fast Fourier transforms (FFTs) and Doppler FFTs on the digital beat signals generated by the first plurality of receive channels to generate per range Doppler slices for each receive channel in the first plurality of receive channels and the second initial portion of signal processing includes computing range FFTs and Doppler FFTs on the digital beat signals generated by the second plurality of receive channels to generate per range Doppler slices for each receive channel in the second plurality of receive channels.

3. The cascaded radar system of claim 2, in which the first radar SOC includes a first memory coupled to the first signal processing component to store results of computing range FFTs and the second radar SOC includes a second memory coupled to the second signal processing component to store results of computing range FFTs.

4. The cascaded radar system of claim 2, in which the first radar SOC and the second radar SOC send Doppler slices for a current range to the processing unit prior to generating Doppler slices for a next range.

5. The cascaded radar system of claim 2, in which the remaining portion of the signal processing includes computing angle FFTs using per range Doppler slices generated by the first radar SOC and the second radar SOC.

6. The cascaded radar system of claim 2, in which the first initial portion of signal processing and the second initial portion of signal processing include performing partial object detection and the remaining portion of the signal processing includes completing object detection and computing angle FFTs for detected objects.

7. The cascaded radar system of claim 6, in which the partial object detection uses a relaxed object detection threshold and the completing object detection uses a stricter object detection threshold.

8. The cascaded radar system of claim 7, in which the partial object detection includes computing a partial coherent power sum and comparing the partial coherent power sum to the relaxed object detection threshold.

9. The cascaded radar system of claim 1, in which the first radar SOC is a master radar SOC and the second radar SOC is a slave radar SOC.

10. A method for distributed radar signal processing in a cascaded radar system, the method comprising:

performing a first initial portion of signal processing for object detection on digital beat signals generated by a first plurality of receive channels in a first radar system-on-a-chip (SOC) in the radar system;

performing a second initial portion of signal processing for object detection on digital beat signals generated by a second plurality of receive channels in a second radar SOC in the radar system; and

performing, by a processing unit in the radar system, a remaining portion of the signal processing for object detection using results of the first initial portion of signal processing and the second initial portion of signal processing.

11. The method of claim 10, in which the first initial portion of signal processing includes computing range fast Fourier transforms (FFT) and Doppler FFTs on the digital beat signals generated by the first plurality of receive channels to generate per range Doppler slices for each receive channel of the first plurality of receive channels and the second initial portion of signal processing includes computing range fast Fourier transforms (FFT) and Doppler FFTs on the digital beat signals generated by the second plurality of receive channels to generate per range Doppler slices for each receive channel of the second plurality of receive channels.

12. The method of claim 11, in which results of computing range FFTs in the first radar SOC are stored in a memory of the first radar SOC and results of computing range FFTs in the second radar SOC are stored in a memory of the second radar SOC.

13. The method of claim 11, in which the first radar SOC and the second radar SOC send Doppler slices for a current range to the processing unit prior to generating Doppler slices for a next range.

14. The method of claim 11, in which the remaining portion of the signal processing includes computing angle FFTs using the per range Doppler slices.

15. The method of claim 11, in which the initial portion of signal processing and the second initial portion of signal processing include performing partial object detection and the remaining portion of the signal processing includes completing object detection and computing angle FFTs for detected objects.

16. The method of claim 15, in which performing partial object detection includes using a relaxed object detection threshold and completing the object detection includes using a stricter object detection threshold.

17. The method of claim 16, in which performing partial object detection includes computing a partial coherent power sum and comparing the partial coherent power sum to the relaxed object detection threshold.

18. The method of claim 10, in which the first radar SOC is a master radar SOC and the second radar SOC is a slave radar SOC.

19. A method for distributed radar signal processing in a cascaded radar system including a plurality of radar systems-on-a-chip (SOC) coupled to a processing unit, the method comprising:

performing an initial portion of signal processing for object detection in each radar SOC; and

performing a remaining portion of the signal processing for object detection in the processing unit using results of performing the initial portion received from each of the radar SOCs.

20. The method of claim 19, in which the initial portion of signal processing includes performing range fast Fourier transforms (FFTs) and Doppler FFTs on digital beat signals to generate per range Doppler slices.