Radar data buffering

• US 9,971,020 B1
• Filed: 02/09/2018
• Issued: 05/15/2018
• Est. Priority Date: 02/10/2017
• Status: Active Grant

• Current Assignee: Uhnder, Inc.
• Original Assignee: Uhnder, Inc.
• Inventors: Maher, Monier, Davis, Curtis, Rush, Frederick, Eshraghi, Aria
• Primary Examiner(s): Barker, Matthew M
• Application Number:
  US15/892,764
• Time in Patent Office: 95 Days
• CPC Class Codes: G01S 13/06 Systems determining position data of a target
• CPC Class Codes: G01S 13/325 using transmission of coded signals, e.g. P.S.K. signals
• CPC Class Codes: G01S 13/34 using transmission of continuous, frequency-modulated waves while heterodyning the received signal, or a signal derived therefrom, with a locally-generated signal related to the contemporaneously transmitted signal
• CPC Class Codes: G01S 13/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S13/46
• CPC Class Codes: G01S 13/584 adapted for simultaneous range and velocity measurements
• CPC Class Codes: G01S 13/64 Velocity measuring systems using range gates
• 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 2013/93271 in the front of the vehicles
• CPC Class Codes: G01S 2013/93272 in the back of the vehicles
• CPC Class Codes: G01S 2013/93274 on the side of the vehicles
• CPC Class Codes: G01S 7/032 Constructional details for solid-state radar subsystems
• CPC Class Codes: G01S 7/285 Receivers
• CPC Class Codes: G01S 7/352 Receivers
• CPC Class Codes: G01S 7/354 Extracting wanted echo-signals Doppler systems G01S13/50
• CPC Class Codes: G01S 7/4017 of HF systems
• CPC Class Codes: G01S 7/4021 of receivers
• CPC Class Codes: G06F 7/724 Finite field arithmetic for error detection or correction in general H03M13/00, in computers G06F11/10
• CPC Class Codes: G11C 11/409 Read-write [R-W] circuits

Abstract

A radar system includes transmitters and receivers configured for installation and use in a vehicle. The transmitters transmit radio signals. The receivers receive radio signals that include the transmitted radio signals reflected from objects in an environment. Each receiver has an RF front end, an analog-to-digital converter (ADC), a digital signal processor, and a controller. The digital signal processor processes the data from the ADC and stores data samples in a buffer. The buffer operates in several modes defined by the controller. These modes include replay mode, loopback mode, quiet mode, and throttle mode. By controlling the buffer, the same received samples can be processed in multiple ways to generate information on targets at different ranges and velocities. The buffer is read out and the data is processed further to enable the radar system to determine range, velocity, and angle of targets in the environment.

Claims

1. A radar sensing system for a vehicle, the radar sensing system comprising:

a plurality of transmitters configured for installation and use on a vehicle and configured to transmit radio signals;

a plurality of receivers configured for installation and use on the vehicle and configured to receive radio signals that include the transmitted radio signals transmitted by the transmitters and reflected from objects in an environment;

a controller configured to control the transmitters and the receivers; and

wherein each receiver of the plurality of receivers comprises;

(i) a radio frequency (RF) front end configured to process the received radio signals to output processed radio signals;

(ii) an analog-to-digital converter (ADC) configured to sample the processed radio signals and output data samples;

(iii) a pre-buffer processor configured to selectively perform signal processing operations on the ADC samples, (iv) a buffer configured to store data samples from the pre-buffer processor, wherein the buffer is configured to operate in one of a plurality of modes as defined by the controller, and wherein the buffer is configured to selectively output the stored data samples, as defined by the controller; and

(v) a post-buffer processor configured to receive data samples output from the buffer, wherein the post-buffer processor is configured to perform at least one of range processing, velocity processing, and angular processing on the stored data samples, as defined by the controller.

2. The radar sensing system of claim 1, wherein each buffer is configured to replay a sequence of stored data samples a plurality of times, and wherein the replayed sequence of stored data samples is processed differently as compared to a previous processing.

3. The radar sensing system of claim 1, wherein each post-buffer processor is configured to perform correlation operations as part of the range processing.

4. The radar sensing system of claim 3, wherein each pre-buffer processor is configured to store samples in the corresponding buffer, and wherein each post-buffer processor is placed into a sleep mode, as defined by the controller, when the corresponding pre-buffer processor is actively storing data samples in the corresponding buffer.

5. The radar sensing system of claim 1, wherein each post-buffer processor is configured to perform complex signal rotation to shift a frequency of the data samples, as defined by the controller.

6. The radar sensing system of claim 1, wherein each post-buffer processor is configured to selectively scale amplitudes of the data samples.

7. The radar sensing system of claim 6, wherein scaling an amplitude comprises setting a data sample to a value of zero.

8. The radar sensing system of claim 1, wherein each post-buffer processor is configured to perform a cyclic redundancy check (CRC) on selected data codes after processing the data samples, as defined by the controller.

9. The radar sensing system of claim 1, wherein each post-buffer processor is configured to use data samples stored in the corresponding buffer to calibrate a radio frequency processing portion of the corresponding RF front end.

10. The radar sensing system of claim 1, wherein each post-buffer processor is configured to use data samples stored in the corresponding buffer to calibrate a digital processing portion of the corresponding RF front end.

11. The radar sensing system of claim 1, wherein each pre-buffer processor is configured to pass the ADC samples directly to the corresponding buffer.

12. A method for controlling a radar sensing system comprising a plurality of transmitters configured for installation and use on a vehicle and a plurality of receivers configured for installation and use on the vehicle, the method comprising:

transmitting, with the transmitters, radio signals;

receiving, with the receivers, radio signals that include the transmitted radio signals transmitted by the transmitters and reflected from objects in an environment;

processing, with a radio frequency (RF) front end of a first receiver of the plurality of receivers, the received radio signals and outputting processed radio signals;

sampling, with an analog-to-digital converter (ADC) of the first receiver, the processed radio signals and outputting data samples;

selectively processing, with a pre-buffer processor of the first receiver, the ADC samples;

storing pre-buffer processor output data samples in a buffer of the first receiver;

selecting one of a plurality of operational modes for the buffer, and outputting the stored data samples as defined by the selected operational mode; and

performing, with a post-buffer processor of the first receiver, at least one of range processing, velocity processing, and angular processing on the stored data samples.

13. The method of claim 12 further comprising replaying, with the buffer, a sequence of data samples a plurality of times, wherein the replayed sequence of data samples is processed differently from a previous processing.

14. The method of claim 12, wherein performing range processing comprises performing correlation operations.

15. The method of claim 12, wherein storing pre-buffer processor output data samples in a buffer comprises storing the data samples output of the pre-buffer processor in the buffer, and placing the post-buffer processor into a sleep mode when the pre-buffer processor is actively storing the data samples in the buffer.

16. The method of claim 12, wherein angular processing comprises performing a complex signal rotation to shift a frequency of the data samples.

17. The method of claim 12 further comprising selectively scaling, with the post-buffer processor, amplitudes of the data samples.

18. The method of claim 17, wherein scaling an amplitude comprises setting a data sample to a value of zero.

19. The method of claim 12 further comprising performing, with the post-buffer processor, a cyclic redundancy check (CRC) on selected data codes after the post-buffer processor has processed the data samples.

20. The method of claim 12 further comprising calibrating, with the post-buffer processor, a radio frequency processing portion of the RF front end using the data samples stored in the buffer.

21. The method of claim 12 further comprising calibrating, with the post-buffer processor, a digital processing portion of the RF front end using the data samples stored in the buffer.

22. The method of claim 12, wherein selectively processing, with a pre-buffer processor of the first receiver, the ADC samples comprises passing the ADC samples directly to the buffer.