PMCW—PMCW interference mitigation

Patent metadata

Field	Value
Publication number	US-10324165-B2
Application number	US-201715712230-A
Country	US
Kind code	B2
Filing date	Sep 22, 2017
Priority date	Apr 25, 2016
Publication date	Jun 18, 2019
Grant date	Jun 18, 2019

Abstract

A radar sensing system for a vehicle includes a transmitter, a receiver, and a processor. The transmitter is configured to transmit a radio signal. The receiver is configured to receive a radio signal which includes the transmitted radio signal reflected from an object in the environment. The receiver is also configured to receive an interfering radio signal transmitted by a transmitter of another radar sensing system. The processor is configured to control the transmitter to mitigate or avoid interference from the other radar sensing system.

First claim

The invention claimed is:

1. A radar sensing system for a vehicle, the radar sensing system comprising:
a transmitter configured for installation and use on a vehicle, and configured to transmit radio signals on a selected carrier frequency, wherein the transmitted radio signals comprise phase modulated continuous wave radio signals;
a receiver configured for installation and use on the vehicle, and configured to receive radio signals that include transmitted radio signals transmitted by the transmitter and reflected from an object in an environment, wherein the receiver is further configured to correlate the received radio signals using a same spreading code as used by the transmitter;
a processor configured to control the transmitter to select a carrier frequency;
wherein the receiver is configured to receive interfering radio signals that include phase modulated radio signals transmitted by another radar sensing system, and wherein received interfering radio signals interfere with the received radio signals; and
wherein the processor is configured to control and alter, as necessary, the phase modulation of the transmitter such that the receiver avoids receiving the interfering radio signals.

2. The radar sensing system of claim 1 , wherein the processor is further configured to control the transmitter to selectively transmit radio signals at the selected carrier frequency in a periodic fashion.

3. The radar sensing system of claim 1 , wherein the processor is further configured to control the transmitter to selectively transmit radio signals at the selected carrier frequency in an aperiodic fashion.

4. The radar sensing system of claim 1 , wherein the selected carrier frequency is selected from a subset of two or more carrier frequencies of a plurality of carrier frequencies.

5. The radar sensing system of claim 1 , wherein the selected carrier frequency is selected from a plurality of carrier frequencies.

6. The radar sensing system of claim 5 , wherein the processor is configured to measure interference levels at each of the carrier frequencies of the plurality of carrier frequencies and to select a carrier frequency for transmission with a lower level of interference than another carrier frequency.

7. The radar sensing system of claim 6 , wherein the processor is further configured to temporarily turn off the transmitter to measure an interference level to detect the presence of other operating radar systems.

8. The radar sensing system of claim 6 , wherein the processor is further configured to select a carrier frequency for transmission based at least in part on an algorithm where carrier frequencies are individually weighted based upon interference level measurements.

9. The radar sensing system of claim 6 , wherein the processor is further configured to measure the interference level in part by determining a noise floor.

10. The radar sensing system of claim 1 , wherein the processor is further configured to mitigate or avoid the interfering radio signals.

11. The radar sensing system of claim 10 , wherein the processor is further configured to control the transmitter to turn off for a period of time when interference from interfering radio signals is detected.

12. The radar sensing system of claim 11 , wherein the processor is further configured to detect the presence of other radar systems by comparing correlation values from different scans when the transmitter is turned off.

13. The radar sensing system of claim 10 , wherein the processor is further configured to control the transmitter to turn off and back on for a variable amount of time when interference from interfering radio signals is detected.

14. The radar sensing system of claim 13 , wherein the processor is further configured to synchronize the transmitter with the other radar sensing system such that the transmitter is not transmitting when the other radar sensing system is transmitting.

15. A radar sensing system for a vehicle, the radar sensing system comprising:
a transmitter configured for installation and use on a vehicle, and configured to transmit radio signals on a selected carrier frequency, wherein the transmitted radio signals are phase modulated continuous wave radio signals;
a receiver configured for installation and use on the vehicle, and configured to receive radio signals that include transmitted radio signals transmitted by the transmitter and reflected from an object in an environment;
a processor configured to control the transmitter to select a carrier frequency;
wherein the receiver is configured to receive interfering radio signals that include radio signals transmitted by another radar sensing system, and wherein received interfering radio signals interfere with the received radio signals;
wherein the processor is configured to control the transmitter such that the receiver avoids receiving the interfering radio signals;
wherein the processor is configured to mitigate or avoid the interfering radio signals; and
wherein the transmitter is further configured to phase modulate the radio signals for transmission according to a spreading code, and wherein the receiver is further configured to correlate the received radio signals using the same spreading code as used by the transmitter, and wherein the receiver is further configured to also correlate the received radio signals with a spreading code that is different from the spreading code used by the transmitter, such that the receiver determines correlation values for the received interfering radio signals without the received radio signal, and wherein the determined correlation values are processed by the processor to determine interference levels corresponding to each carrier frequency of the plurality of carrier frequencies.

16. A radar sensing system for a vehicle, the radar sensing system comprising:
a transmitter configured for installation and use on a vehicle, and configured to transmit radio signals on a selected carrier frequency, wherein the transmitted radio signals are phase modulated continuous wave radio signals;
a receiver configured for installation and use on the vehicle, and configured to receive radio signals that include transmitted radio signals transmitted by the transmitter and reflected from an object in an environment;
a processor configured to control the transmitter to select a carrier frequency;
wherein the receiver is configured to receive interfering radio signals that include radio signals transmitted by another radar sensing system, and wherein received interfering radio signals interfere with the received radio signals;
wherein the processor is configured to control the transmitter such that the receiver avoids receiving the interfering radio signals;
wherein the processor is configured to mitigate or avoid the interfering radio signals; and
wherein the transmitter is further configured to phase modulate the radio signals for transmission according to an aperiodic spreading code, and wherein the receiver is further configured to measure a noise floor of the received radio signals, and wherein the processor is further configured to switch the transmitter to a periodic spreading code when the noise floor increases above a threshold, and wherein both radar sensing systems have the same period.

17. The radar sensing system of claim 10 , wherein the processor is further configured to mitigate interference from the other radar sensing system by varying a signal bandwidth of the transmitted radio signal, and wherein the transmitted signal bandwidth is varied by adjusting a chip rate of a spreadin

Assignees

• Uhnder Inc

Inventors

• Bordes Jean P
• Davis Curtis
• Stark Wayne E
• Schmid Otto A
• Rao Raghunath K

Classifications

• G01S7/0233

  Avoidance by phase multiplex · CPC title

• G01S2013/93271

  in the front of the vehicles · CPC title

• G01S2013/93272

  in the back of the vehicles · CPC title

• G01S2013/9321

  Velocity regulation, e.g. cruise control · CPC title

• G01S13/931

  of land vehicles · CPC title