Adaptive algorithms for interrogating the viewable scene of an automotive radar

• US 10,222,462 B2
• Filed: 01/13/2016
• Issued: 03/05/2019
• Est. Priority Date: 02/27/2013
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Waymo LLC (Alphabet Inc.)
• Inventors: Brown, Adam
• Primary Examiner(s): Gregory, Bernarr E
• Application Number:
  US14/994,902
• Publication Number:
  US 20160131753A1
• Time in Patent Office: 1,147 Days
• Field of Search: 342159, 342162
• CPC Class Codes: G01S 13/10 using transmission of interrupted, pulse modulated waves determination of distance by phase measurement G01S13/32
• 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 13/86 Combinations of radar systems with non-radar systems, e.g. sonar, direction finder
• CPC Class Codes: G01S 13/862 Combination of radar systems with sonar systems
• CPC Class Codes: G01S 13/865 Combination of radar systems with lidar systems
• CPC Class Codes: G01S 13/867 Combination of radar systems with cameras
• 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 2013/93275 in the bumper area

Abstract

A radar system in an autonomous vehicle may be operated in various modes and with various configurations. In one example, the radar system determines a target range for further interrogation. The target range may be determined based on the radar system transmitting a first electromagnetic radiation signal and receiving a first reflected electromagnetic signal radiation signal. After the radar system determines a target range, it transmits a second electromagnetic radiation signal. Additionally, the radar system receives a reflected electromagnetic signal radiation based on the transmission. After receiving the reflected signal, the radar system can process the reflected signal to only have components associated with the target range. The processing of the reflected signal may create a processed signal. Finally, the radar system may determine at least one parameter of a target object based on the processed signal.

Claims

1. A method for operating a radar system comprising:

transmitting a first electromagnetic radiation signal via a transceiver of a radar unit;

receiving a first reflected electromagnetic radiation signal based on the first transmitted electromagnetic radiation signal via the transceiver of the radar unit;

determining a target range via a processing unit based on the first reflected electromagnetic radiation signal;

transmitting a second electromagnetic radiation signal via the transceiver of the radar unit;

receiving a second reflected electromagnetic signal radiation based on the second transmitted electromagnetic radiation signal via the transceiver of the radar unit;

processing the received second reflected electromagnetic signal via the processing unit to provide a processed signal by removing components of the received second reflected electromagnetic signal associated with objects outside the target range through mixing the received second reflected electromagnetic signal with the transmitted signal and wherein the mixing forms a range-dependent beat pattern; and

determining at least one parameter of a target object based on the processed signal, wherein the at least one parameter comprises at least one of a distance and an angle to the target object.

2. The method of claim 1, wherein at least one of the first electromagnetic radiation signal and the second electromagnetic radiation signal comprises a signal according to a synthetic aperture radar operating mode.

3. The method of claim 1, wherein at least one of the first electromagnetic radiation signal and the second electromagnetic radiation signal comprises a signal according to a pulsed operating mode.

4. The method of claim 1, wherein at least one of the first electromagnetic radiation signal and the second electromagnetic radiation signal comprises a signal according to a stepped frequency operating mode.

5. The method of claim 1, wherein the receiving is performed with a plurality of antennas forming an array.

6. The method of claim 1, wherein the transmitting is performed with at least one antenna.

7. The method of claim 1, wherein processing the received second reflected electromagnetic signal comprises removing a portion of the second reflected electromagnetic signal based on a frequency component of the portion of the second reflected electromagnetic signal, wherein the portion of the second reflected electromagnetic signal is removed based on:

(i) the frequency component of the portion of the second reflected electromagnetic signal, (ii) a frequency component of a portion of the second electromagnetic radiation signal, and (iii) a time delay.

8. A radar system comprising:

an antenna system configured to transmit and receive electromagnetic radiation;

a transceiver configured to cause the antenna system to;

transmit a first electromagnetic radiation signal;

receive a first reflected electromagnetic signal radiation based on the first transmitted electromagnetic radiation signal;

transmit a second electromagnetic radiation signal; and

receive a second reflected electromagnetic signal radiation based on the second transmitted electromagnetic radiation signal; and

a processing unit configured to;

determine a target range based on the first reflected electromagnetic radiation signal;

process the received second reflected electromagnetic signal to provide a processed signal by removing components of the received second reflected electromagnetic signal associated with objects outside the target range through mixing the received second reflected electromagnetic signal with the transmitted signal and wherein the mixing forms a range-dependent beat pattern; and

determine at least one parameter of the target object based on the processed signal, wherein the at least one parameter comprises at least one of a distance and an angle to the target object.

9. The radar system of claim 8, wherein the transceiver is further configured to transmit at least one of the first electromagnetic radiation signal and the second electromagnetic radiation signal comprises a signal according to a synthetic aperture radar operating mode.

10. The radar system of claim 8, wherein the transceiver is further configured to transmit at least one of the first electromagnetic radiation signal and the second electromagnetic radiation signal according to a pulsed operating mode.

11. The radar system of claim 8, wherein the transceiver is further configured to transmit at least one of the first electromagnetic radiation signal and the second electromagnetic radiation signal according to a stepped frequency operating mode.

12. The radar system of claim 11, wherein at least one antenna from the plurality of antennas transmits the first electromagnetic radiation signal.

13. The radar system of claim 8, wherein the antenna system comprises a plurality of antennas forming an array.

14. The radar system of claim 8, wherein the processing unit is further configured to remove a portion of the second reflected electromagnetic signal based on a frequency component of the portion of the second reflected electromagnetic signal, wherein the portion of the second reflected electromagnetic signal is removed based on:

(i) the frequency component of the portion of the second reflected electromagnetic signal, (ii) a frequency component of a portion of the second electromagnetic radiation signal, and (iii) a time delay.

15. An article of manufacture including a non-transitory computer-readable medium having stored thereon program instructions that, when executed by a processor in a radar system, cause the radar system to perform operations comprising:

determining a target range;

causing the transmission of an electromagnetic radiation signal via a transceiver of a radar unit;

processing a received reflected electromagnetic signal received via the transceiver of the radar unit to provide a processed signal by removing components of the received second reflected electromagnetic signal associated with objects outside the target range through mixing the received second reflected electromagnetic signal with the transmitted signal and wherein the mixing forms a range-dependent beat pattern; and

determining at least one parameter of the target object based on the processed signal, wherein the at least one parameter comprises at least one of a distance and an angle to the target object.

16. The article of manufacture of claim 15, wherein processing the received reflected electromagnetic signal comprises removing a portion of the reflected electromagnetic signal based on a frequency component of the portion of the reflected electromagnetic signal.

17. The article of manufacture of claim 16, wherein the portion of the reflected electromagnetic signal is removed based on:

(i) the frequency component of the portion of the reflected electromagnetic signal, (ii) a frequency component of a portion of the electromagnetic radiation signal, and (iii) a time delay.

18. The article of manufacture of claim 15, wherein determining a target range comprises:

causing the transmission of a first electromagnetic radiation signal;

processing a first reflected electromagnetic signal radiation based on the first transmitted electromagnetic radiation signal.