Scalable architecture for an automotive radar system

• US 10,175,352 B2
• Filed: 05/10/2016
• Issued: 01/08/2019
• Est. Priority Date: 05/12/2015
• Status: Active Grant

• Current Assignee: Maxlinear Incorporated
• Original Assignee: Maxlinear Incorporated
• Inventors: Ling, Curtis
• Primary Examiner(s): Gregory, Bernarr E
• Application Number:
  US15/150,669
• Publication Number:
  US 20160334504A1
• Time in Patent Office: 973 Days
• CPC Class Codes: G01S 13/0209 Systems with very large relative bandwidth, i.e. larger than 10 %, e.g. baseband, pulse, carrier-free, ultrawideband
• CPC Class Codes: G01S 13/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S13/46
• CPC Class Codes: G01S 13/60 wherein the transmitter and receiver are mounted on the moving object, e.g. for determining ground speed, drift angle, ground track G01S13/64 takes precedence
• CPC Class Codes: G01S 13/86 Combinations of radar systems with non-radar systems, e.g. sonar, direction finder
• CPC Class Codes: G01S 13/87 Combinations of radar systems, e.g. primary radar and secondary radar
• CPC Class Codes: G01S 13/89 for mapping or imaging
• 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 2013/93273 on the top of the vehicles
• CPC Class Codes: G01S 2013/93274 on the side of the vehicles
• CPC Class Codes: G01S 2013/93275 in the bumper area
• CPC Class Codes: G01S 2013/93276 in the windshield area
• CPC Class Codes: G01S 7/006 using shared front-end circuitry, e.g. antennas G01S13/765, G01S13/825 take precedence
• CPC Class Codes: G01S 7/4021 of receivers
• CPC Class Codes: G01S 7/4026 Antenna boresight

Abstract

First transmitter circuitry communicates, via bus interface circuitry, on a data bus to detect whether any second transmitter circuitry is coupled to the data bus. In instances that no second transmitter circuitry is detected as being coupled to the data bus, the first transmitter circuitry transmits beamformed signals via a first plurality of antenna elements using beamforming coefficients. In instances that second transmitter circuitry is detected as being coupled to the data bus, the first transmitter circuitry determines a phase offset between clock generation circuitry of the first transmitter circuitry and clock generation circuitry of the detected second transmitter circuitry. The first transmitter circuitry compensates the beamforming coefficients based on the determined phase offset. The first transmitter circuitry use the compensated beamforming coefficients for transmitting signals that are phase coherent with signals transmitted by the second transmitter circuitry.

Claims

1. A method comprising:

communicating, via bus interface circuitry of first transmitter circuitry, on a data bus to detect whether any second transmitter circuitry is coupled to the data bus;

in instances that no second transmitter circuitry is detected as being coupled to the data bus;

transmitting, by the first transmitter circuitry, beamformed signals via a first plurality of antenna elements using beamforming coefficients; and

in instances that second transmitter circuitry is detected as being coupled to the data bus;

determining, by the first transmitter circuitry, a phase offset between clock generation circuitry of the first transmitter circuitry and clock generation circuitry of the detected second transmitter circuitry;

compensating, by the first transmitter circuitry, the beamforming coefficients based on the determined phase offset; and

generating and transmitting, by the first transmitter circuitry using the compensated beamforming coefficients, compensated signals that are phase coherent with other signals transmitted by the detected second transmitter circuitry via a second plurality of antenna elements.

2. The method of claim 1, wherein the determining the phase offset comprises the first transmitter circuitry:

transmitting, during a calibration period, calibration signals via the first plurality of antenna elements; and

adjusting the beamforming coefficients during the transmitting the calibration signals such that a transmit antenna pattern of the calibration signal sweeps over a range of angles during the calibration period.

3. The method of claim 2 comprising generating, by the first transmitter circuitry, the calibration signals by modulating a millimeter wave radar burst.

4. The method of claim 3, wherein the determining the phase offset comprises the first transmitter circuitry receiving, via the data bus during the calibration period, an indication of a strength of a reflection of the calibration signals received by receiver circuitry coupled to the data bus.

5. The method of claim 4, comprising demodulating, by the receiver circuitry, the calibration signals to recover information modulated on the calibration signal.

6. The method of claim 2, wherein the range of angles encompasses the angle between the first transmitter circuitry and a known location of an object off which the calibration signal is to reflect.

7. The method of claim 1, wherein, in the instances that the second transmitter circuitry is detected coupled to the data bus, generating, by the first transmitter circuitry, the compensated signals by modulating a millimeter wave radar burst.

8. The method of claim 7, wherein data modulated onto the millimeter wave radar burst during the modulating is intended for receiver circuitry that is coupled to the data bus.

9. The method of claim 1, wherein, in the instances that no second transmitter circuitry is detected as being coupled to the data bus, generating, by the first transmitter circuitry, the beamformed signals by modulating a millimeter wave radar burst.

10. The method of claim 9, wherein data modulated onto the millimeter wave radar burst during the modulating is intended for receiver circuitry that is coupled to the data bus.

11. A system comprising:

first transmitter circuitry that comprises bus interface circuitry and clock generation circuitry, and is operable to;

communicate, via the bus interface circuitry, on a data bus to detect whether any second transmitter circuitry is coupled to the data bus;

in instances that no second transmitter circuitry is detected as being coupled to the data bus, transmit, by the first transmitter circuitry, beamformed signals via a first plurality of antenna elements using beamforming coefficients; and

in instances that second transmitter circuitry is detected as being coupled to the data bus;

determine, by the first transmitter circuitry, a phase offset between clock generation circuitry of the first transmitter circuitry and clock generation circuitry of the detected second transmitter circuitry;

compensate, by the first transmitter circuitry, the beamforming coefficients based on the determined phase offset; and

generate, by the first transmitter circuitry using the compensated beamforming coefficients, compensated signals such that the compensated signals, when transmitted via the first plurality of antenna elements, are phase coherent with other signals transmitted by the detected second transmitter circuitry via a second plurality of antenna elements.

12. The system of claim 11, wherein the determination of the phase offset comprises:

transmission, during a calibration period, of calibration signals via the first plurality of antenna elements; and

adjustment of the beamforming coefficients during the transmission of the calibration signals such that a transmit antenna pattern of the calibration signal sweeps over a range of angles during the calibration period.

13. The system of claim 12 wherein the first transmitter circuitry is operable to modulate a millimeter wave radar burst to generate the calibration signals.

14. The system of claim 13, comprising receiver circuitry coupled to the data bus, wherein the first transmitter circuitry is operable to:

receive, via the data bus during the calibration period, an indication of a strength of a reflection of the calibration signals received by the receiver circuitry; and

use the indication of strength of the reflection for the determination of the phase offset.

15. The system of claim 14, wherein the receiver circuitry is operable to demodulate the calibration signals to recover information modulated on the calibration signal.

16. The system of claim 12, wherein the range of angles encompasses the angle between the first transmitter circuitry and a known location of an object off which the calibration signal is to reflect.

17. The system of claim 11, wherein the first transmitter circuitry is operable to, in the instances that second transmitter circuitry is detected coupled to the data bus, modulate a millimeter wave radar burst to generate the compensated signals.

18. The system of claim 17, wherein data modulated onto the millimeter wave radar burst is intended for receiver circuitry that is coupled to the data bus.

19. The system of claim 11, wherein the first transmitter circuitry is operable to, in the instances that no second transmitter circuitry is detected as being coupled to the data bus, generate the beamformed signals by modulating a millimeter wave radar burst.

20. The system of claim 19, wherein data modulated onto the millimeter wave radar burst is intended for receiver circuitry that is coupled to the data bus.