US-12625243-B2 - Opportunistic passive multistatic radar processing for automotive radar

Abstract

Various technologies described herein pertain to opportunistically employing passive multistatic radar processing in automotive radar systems. A radar system of an autonomous vehicle is controlled to operate in an active mode during a first time period as the autonomous vehicle travels along a route. A transmitter and receiver of the radar system are enabled in the active mode. The radar system is controlled to operate in a passive mode during a second time period as the autonomous vehicle travels along the route. The transmitter is disabled and receiver is enabled in the passive mode. While in the passive mode, the receiver of the radar system receives a reflected radar signal responsive to a radar signal transmitted by a differing radar system of a differing autonomous vehicle. An object is detected based on the reflected radar signal and transmission information pertaining to the differing radar system of the differing autonomous vehicle.

Inventors

• Michael J. Hamilton
• Christoph SCHWARK

Assignees

• GM CRUISE HOLDINGS LLC

Dates

Publication Date

20260512

Application Date

20230424

Claims (20)

1. 1 . A server computing system, comprising: a processor; and memory that stores computer-executable instructions that, when executed by the processor, cause the processor to perform acts comprising: identifying that a first radar system of a first autonomous vehicle and a second radar system of a second autonomous vehicle are likely to experience cross-radar interference during a time period as the first autonomous vehicle travels along a first route through a driving environment and the second autonomous vehicle travels along a second route through the driving environment, wherein the first autonomous vehicle and the second autonomous vehicle are in a fleet of autonomous vehicles; selecting the first radar system of the first autonomous vehicle to operate in an active mode and the second radar system of the second autonomous vehicle to operate in a passive mode during the time period, wherein a first transmitter and a first receiver of the first radar system of the first autonomous vehicle are both enabled when operating in the active mode, and wherein a second transmitter of the second radar system of the second autonomous vehicle is disabled and a second receiver of the second radar system of the second autonomous vehicle is enabled when operating in the passive mode; and transmitting, to the second autonomous vehicle, a control signal to cause the second radar system to operate in the passive mode during the time period, wherein the first radar system of the first autonomous vehicle is selected to operate in the active mode and the second radar system of the second autonomous vehicle is selected to operate in the passive mode during the time period based on relative priorities of driving maneuvers to be performed by the first autonomous vehicle and the second autonomous vehicle.
2. 2 . The server computing system of claim 1 , the acts further comprising: transmitting, to the first autonomous vehicle, a control signal to cause the first radar system to operate in the active mode during the time period, or transmission information pertaining to the first radar system of the first autonomous vehicle.
3. 3 . The server computing system of claim 2 , wherein the transmission information pertaining to the first radar system comprises location information specifying a location of the first radar system, or at least one of waveform information specifying a waveform of a radar signal transmitted by the first transmitter of the first radar system or timing information specifying timing of the radar signal transmitted by the first transmitter of the first radar system.
4. 4 . The server computing system of claim 1 , wherein the first radar system of the first autonomous vehicle and the second radar system of the second autonomous vehicle are identified as likely to experience cross-radar interference based on a distance between the first radar system and the second radar system, a first field of view of the first radar system, and a second field of view of the second radar system.
5. 5 . The server computing system of claim 1 , wherein the first radar system of the first autonomous vehicle is selected to operate in the active mode and the second radar system of the second autonomous vehicle is selected to operate in the passive mode during the time period based on relative locations of the first radar system and the second radar system and directions towards which it is desired to detect objects from the first radar system and the second radar system.
6. 6 . The server computing system of claim 1 , the acts further comprising: selecting the first radar system of the first autonomous vehicle to operate in the passive mode during a differing time period as the first autonomous vehicle travels along the first route through the driving environment, wherein the first transmitter of the first radar system of the first autonomous vehicle is disabled and the first receiver of the first radar system of the first autonomous vehicle is enabled when operating in the passive mode; and transmitting, to the first autonomous vehicle, a control signal to cause the first radar system to operate in the passive mode during the differing time period.
7. 7 . The server computing system of claim 1 , the acts further comprising: selecting the second radar system of the second autonomous vehicle to operate in the active mode during a differing time period as the second autonomous vehicle travels along the second route through the driving environment, wherein the second transmitter and the second receiver of the second radar system of the second autonomous vehicle are both enabled when operating in the active mode; and transmitting, to the second autonomous vehicle, a control signal to cause the second radar system to operate in the active mode during the differing time period.
8. 8 . A server computing system, comprising: a processor; and memory that stores computer-executable instructions that, when executed by the processor, cause the processor to perform acts comprising: identifying that a first radar system of a first autonomous vehicle and a second radar system of a second autonomous vehicle are likely to experience cross-radar interference during a time period as the first autonomous vehicle travels along a first route through a driving environment and the second autonomous vehicle travels along a second route through the driving environment, wherein the first autonomous vehicle and the second autonomous vehicle are in a fleet of autonomous vehicles; selecting the first radar system of the first autonomous vehicle to operate in an active mode and the second radar system of the second autonomous vehicle to operate in a passive mode during the time period, wherein a first transmitter and a first receiver of the first radar system of the first autonomous vehicle are both enabled when operating in the active mode, and wherein a second transmitter of the second radar system of the second autonomous vehicle is disabled and a second receiver of the second radar system of the second autonomous vehicle is enabled when operating in the passive mode; and transmitting, to the second autonomous vehicle, a control signal to cause the second radar system to operate in the passive mode during the time period, wherein the first radar system of the first autonomous vehicle is selected to operate in the active mode and the second radar system of the second autonomous vehicle is selected to operate in the passive mode during the time period based on an estimate of information obtained from a target from bistatic measurement.
9. 9 . The server computing system of claim 8 , the acts further comprising: transmitting, to the first autonomous vehicle, a control signal to cause the first radar system to operate in the active mode during the time period, or transmission information pertaining to the first radar system of the first autonomous vehicle.
10. 10 . The server computing system of claim 9 , wherein the transmission information pertaining to the first radar system comprises location information specifying a location of the first radar system, or at least one of waveform information specifying a waveform of a radar signal transmitted by the first transmitter of the first radar system or timing information specifying timing of the radar signal transmitted by the first transmitter of the first radar system.
11. 11 . The server computing system of claim 8 , wherein the first radar system of the first autonomous vehicle and the second radar system of the second autonomous vehicle are identified as likely to experience cross-radar interference based on a distance between the first radar system and the second radar system, a first field of view of the first radar system, and a second field of view of the second radar system.
12. 12 . The server computing system of claim 8 , wherein the first radar system of the first autonomous vehicle is selected to operate in the active mode and the second radar system of the second autonomous vehicle is selected to operate in the passive mode during the time period based on relative locations of the first radar system and the second radar system and directions towards which it is desired to detect objects from the first radar system and the second radar system.
13. 13 . The server computing system of claim 8 , the acts further comprising: selecting the first radar system of the first autonomous vehicle to operate in the passive mode during a differing time period as the first autonomous vehicle travels along the first route through the driving environment, wherein the first transmitter of the first radar system of the first autonomous vehicle is disabled and the first receiver of the first radar system of the first autonomous vehicle is enabled when operating in the passive mode; and transmitting, to the first autonomous vehicle, a control signal to cause the first radar system to operate in the passive mode during the differing time period.
14. 14 . The server computing system of claim 8 , the acts further comprising: selecting the second radar system of the second autonomous vehicle to operate in the active mode during a differing time period as the second autonomous vehicle travels along the second route through the driving environment, wherein the second transmitter and the second receiver of the second radar system of the second autonomous vehicle are both enabled when operating in the active mode; and transmitting, to the second autonomous vehicle, a control signal to cause the second radar system to operate in the active mode during the differing time period.
15. 15 . A server computing system, comprising: a processor; and memory that stores computer-executable instructions that, when executed by the processor, cause the processor to perform acts comprising: identifying that a first radar system of a first autonomous vehicle and a second radar system of a second autonomous vehicle are likely to experience cross-radar interference during a time period as the first autonomous vehicle travels along a first route through a driving environment and the second autonomous vehicle travels along a second route through the driving environment, wherein the first autonomous vehicle and the second autonomous vehicle are in a fleet of autonomous vehicles; selecting the first radar system of the first autonomous vehicle to operate in an active mode and the second radar system of the second autonomous vehicle to operate in a passive mode during the time period, wherein a first transmitter and a first receiver of the first radar system of the first autonomous vehicle are both enabled when operating in the active mode, and wherein a second transmitter of the second radar system of the second autonomous vehicle is disabled and a second receiver of the second radar system of the second autonomous vehicle is enabled when operating in the passive mode; and transmitting, to the second autonomous vehicle, a control signal to cause the second radar system to operate in the passive mode during the time period, wherein the first radar system of the first autonomous vehicle is selected to operate in the active mode and the second radar system of the second autonomous vehicle is selected to operate in the passive mode during the time period based on respective numbers of radar systems of differing autonomous vehicles in the fleet of autonomous vehicles from which radar signals are receivable by the first radar system and the second radar system.
16. 16 . The server computing system of claim 15 , the acts further comprising: transmitting, to the first autonomous vehicle, a control signal to cause the first radar system to operate in the active mode during the time period, or transmission information pertaining to the first radar system of the first autonomous vehicle.
17. 17 . The server computing system of claim 16 , wherein the transmission information pertaining to the first radar system comprises location information specifying a location of the first radar system, or at least one of waveform information specifying a waveform of a radar signal transmitted by the first transmitter of the first radar system or timing information specifying timing of the radar signal transmitted by the first transmitter of the first radar system.
18. 18 . The server computing system of claim 15 , wherein the first radar system of the first autonomous vehicle and the second radar system of the second autonomous vehicle are identified as likely to experience cross-radar interference based on a distance between the first radar system and the second radar system, a first field of view of the first radar system, and a second field of view of the second radar system.
19. 19 . The server computing system of claim 15 , wherein the first radar system of the first autonomous vehicle is selected to operate in the active mode and the second radar system of the second autonomous vehicle is selected to operate in the passive mode during the time period based on relative locations of the first radar system and the second radar system and directions towards which it is desired to detect objects from the first radar system and the second radar system.
20. 20 . The server computing system of claim 15 , the acts further comprising: selecting the first radar system of the first autonomous vehicle to operate in the passive mode during a differing time period as the first autonomous vehicle travels along the first route through the driving environment, wherein the first transmitter of the first radar system of the first autonomous vehicle is disabled and the first receiver of the first radar system of the first autonomous vehicle is enabled when operating in the passive mode; and transmitting, to the first autonomous vehicle, a control signal to cause the first radar system to operate in the passive mode during the differing time period.

Description

RELATED APPLICATION This application claims priority to European Patent Application No. 23169362.3, filed on Apr. 24, 2023, and entitled “OPPORTUNISTIC PASSIVE MULTISTATIC RADAR PROCESSING FOR AUTOMOTIVE RADAR”. The entirety of this application is incorporated herein by reference. BACKGROUND An autonomous vehicle perceives objects surrounding the autonomous vehicle based upon the sensor signals generated by sensor systems of the autonomous vehicle to enable navigating a driving environment. For example, the autonomous vehicle may include various sensor systems, such as a radar system, a camera system and/or a lidar system, for generating sensor signals. The autonomous vehicle also includes a centralized processing device that receives data based upon the sensor signals generated by the sensor systems and performs a variety of different tasks, such as detection of vehicles, pedestrians, and other objects. Based on an output of the processing device, the autonomous vehicle may perform a driving maneuver. As the number of autonomous vehicles that operate in a driving environment increase, instances of cross-radar interference likewise increase. Moreover, some autonomous vehicles include a plurality of radar systems, which also leads to increased instances of cross-radar interference. When autonomous vehicles are within proximity of each other (e.g., within radar range), radar systems of the autonomous vehicles can interfere with each other. Within a fleet of autonomous vehicles, cross-radar interference can be more problematic since radar systems of the autonomous vehicles in the fleet are oftentimes time synchronized. For instance, the radar systems of the autonomous vehicles in a fleet can be offset at specific millisecond triggers from integer seconds from vehicle clocks. Further, the vehicle clocks can be closely synchronized with global positioning system (GPS) signals. As a result, the radar systems from multiple autonomous vehicles in the fleet can operate during common time periods, which increases the likelihood of overlapping signals entering acquisition windows of at least some of the radar systems. According to an illustration, radar systems of two autonomous vehicles operating within proximity can interfere with each other due to timing synchronization between the radar systems. Following this illustration, the radar systems of the autonomous vehicles can each include a transmitter and a receiver. A first transmitter of the first radar system of the first autonomous vehicle and a second transmitter of the second radar system of the second autonomous vehicle can both transmit radar signals into a driving environment during substantially similar time periods. Accordingly, a first receiver of the first radar system can receive, from the driving environment, a reflected radar signal responsive to the radar signal transmitted by the first transmitter of the first radar system as well as an interfering radar signal responsive to the radar signal transmitted by the second transmitter of the second radar system. Similarly, a second receiver of the second radar system can receive, from the driving environment, a reflected radar signal responsive to the radar signal transmitted by the second transmitter of the second radar system as well as an interfering radar signal responsive to the radar signal transmitted by the first transmitter of the first radar system. Thus, in such a scenario, cross-radar interference can be experienced by the first radar system and the second radar system of the autonomous vehicles, which detrimentally impacts operation of the radar systems as well as the autonomous vehicles that include the radar systems. SUMMARY The following is a brief summary of subject matter that is described in greater detail herein. This summary is not intended to be limiting as to the scope of the claims. Described herein are various technologies in which automotive radar systems opportunistically employ passive multistatic radar processing. An autonomous vehicle includes a radar system, which includes a transmitter and a receiver. The radar system can be controlled to operate in an active mode during a first time period as the autonomous vehicle travels along a route through the driving environment. Both the transmitter and the receiver of the radar system are enabled when operating in the active mode. Moreover, the radar system can be controlled to operate in a passive mode during a second time period as the autonomous vehicle travels along the route through the driving environment. The transmitter of the radar system is disabled and the receiver of the radar system is enabled when operating in the passive mode. While operating in the passive mode, the receiver of the radar system can receive a reflected radar signal from the driving environment; the reflected radar signal can be responsive to a radar signal transmitted by a differing radar system of a differing autonomous vehicle operating within prox