Battery management for C-V2X (cellular vehicle to everything)

Abstract

When the parked motor vehicle is located at a hazardous location, both a cellular vehicle-to-everything (C-V2X) modem of the parked motor vehicle and a global navigation satellite system (GNSS) engine of the parked motor vehicle are turned on to increase security relative to turning off the C-V2X modem by causing the C-V2X modem to continue sending C-V2X messages. Both the GNSS engine and the C-V2X modem are turned off to reduce battery power consumption relative to turning on both the GNSS engine and the C-V2X modem when the parked motor vehicle is not located at a dangerous location but at a known long parking location.

Description

Technical Field

[0001] Embodiments of the present invention generally relate to battery management for C-V2X (cellular vehicle to everything). Background Technology

[0002] V2X (Vehicle-to-Everything) communication enables safe, reliable, and efficient transportation services. C-V2X is an important emerging technology developed within 3GPP (3rd Generation Partnership Project) and is designed to operate in both vehicle-to-vehicle and vehicle-to-network modes. V2X communication generates real-time and highly reliable information about the underlying vehicles to enable safe, efficient, and environmentally conscious transportation services and lays the foundation for connected and autonomous driving. C-V2X has enormous potential to enhance vehicle traffic management globally. It can help alleviate problems such as traffic congestion, increased fuel consumption, road safety, and minimized road capacity. It provides the infrastructure for vehicles to communicate with each other and with things around them, offering comprehensive non-line-of-sight perception and a higher level of predictability for better road safety and autonomous driving.

[0003] C-V2X is a 3GPP standard for V2X applications, such as autonomous vehicles. It is an alternative to 802.11p (i.e., DSRC), the IEEE-specified standard for V2V and other forms of V2X communication.

[0004] C-V2X is designed to operate in two modes: (1) Device to network: communication using regular cellular links for V2N (vehicle to network) applications (such as cloud services in end-to-end solutions); and (2) Device to device: direct communication without the use of network dispatch for V2V (vehicle to vehicle), V2I (vehicle to infrastructure), and V2P (vehicle to pedestrian) applications (including but not limited to: vulnerable road user protection; and toll collection).

[0005] In device-to-network mode, C-V2X can use 3GPP-standardized 4G LTE, 5G, or any other suitable protocol in mobile cellular connectivity to exchange messages between vehicles, pedestrians, and roadside traffic control equipment such as traffic signals. It commonly uses the 5.9 GHz frequency band, which is the officially designated Intelligent Transportation Systems (ITS) frequency in most countries. C-V2X can operate without network assistance and extends beyond the DSRC range by approximately 25% to over 100%.

[0006] C-V2X was developed within the 3rd Generation Partnership Project (3GPP) to replace DSRC in the United States and C-ITS in Europe.

[0007] C-V2X sidelink transmission mode 4 communication relies on a distributed resource allocation scheme (i.e., sense-based semi-permanent scheduling), which schedules radio resources independently in each user equipment. It also forms the basis for the direct PC5 air link interface used by V2V / V2I / V2P for communication with nearby vehicles, infrastructure (C-V2X roadside units), and pedestrians.

[0008] Vehicles using V2V / V2I / V2P networks broadcast their Basic Safety Messages (BSMs) to nearby C-V2X-equipped vehicles, roadside units, and pedestrians. BSMs include an identifier, timestamp, location in longitude and latitude, heading, speed, and other vehicle safety information. Additionally, through V2I TIM (Traveler Information Messages) and CAM (Cooperative Awareness Messages) messages, vehicles can receive information about road events, road construction, weather warnings, intersections, and other traffic conditions.

[0009] Dual Subscriber Identity Module (SIM) Dual Active (DSDA) User Equipment (UE) can use two SIMs and two radios to maintain two active calls simultaneously. For example, a DSDA UE can receive a second call while making a first call, and can switch between the two calls without dropping the connection.

[0010] RAT (Radio Access Technology) refers to the various connectivity technologies used in mobile networks, including but not limited to 3G, 4G LTE, C-V2X, 5G, etc. The power consumption of cellular modems generally increases as the RAT evolves from one standard to a subsequent standard.

[0011] In the context of motor vehicle telematics, cellular modems are involved in connecting automotive applications. When the vehicle ignition is turned off, the modem typically remains on to receive telematics commands over the air, such as remotely unlocking doors, while other application processors (typically high-performance CPUs) enter power-down mode to conserve the vehicle's battery.

[0012] Adding a C-V2X RAT to the Telematics Control Unit (TCU) will further increase power consumption from the cellular modem, and since C-V2X operation typically requires the application processor and GNSS (Global Navigation Satellite System) engine to remain on to process the associated high-throughput real-time data, improvements to such battery management solutions will advance existing technologies.

[0013] When the vehicle's ignition is turned off, if C-V2X remains on, GNSS will continue to operate to provide location information used by C-V2X along with C-V2X applications running on the application processor. Power consumption could be 100 times greater or more compared to the same TCU under the same conditions but where the C-V2X modem and GNSS engine are not operating. For example: Configuration type Power consumption budget - mW (at 12 volts) TCU application processor suspended, LTE in standby, C-V2X disconnected, GNSS disconnected. 36 TCU application processor on, LTE standby, C-V2X on, GNSS on. 4500

[0014] For example, the average car battery has a full capacity of approximately 480-1200 watt-hours. If a vehicle is not operated for an extended period (e.g., 2 weeks) and C-V2X remains on while the ignition is off, the vehicle's battery power will be significantly affected (e.g., there will not be enough charge to start the car upon return). Summary of the Invention

[0015] According to embodiments of the invention, when a parked vehicle is in a dangerous location, both the cellular vehicle-to-everything (C-V2X) modem and the Global Navigation Satellite System (GNSS) engine of the parked vehicle are connected to increase safety by allowing the C-V2X modem to continue transmitting C-V2X messages, relative to shutting down the C-V2X modem. When the parked vehicle is not in a dangerous location but in a known long-term parking position, both the GNSS engine and the C-V2X modem are shut down to reduce battery power consumption relative to keeping both the GNSS engine and the C-V2X modem connected. Attached Figure Description

[0016] Figure 1 An example operating environment for embodiments of the present invention is described.

[0017] Figure 2 A schematic block diagram of a system according to an embodiment of the present invention is depicted.

[0018] Figure 3 This is a flowchart depicting a process according to an embodiment of the present invention.

[0019] Figure 4 This is a top view of a local vehicle, a remote vehicle, and a hazardous area according to an embodiment of the present invention.

[0020] Figure 5 The steps for determining hazardous locations according to an embodiment of the present invention are described.

[0021] Figure 6 The invention describes a C-V2X reaching the TCU (Telematics Processing Control Unit).

[0022] Figure 7This illustrates a method by which a remote information processing control unit 704 forms and transmits BSM messages via C-V2X according to an embodiment of the present invention.

[0023] Figure 8 PC5 V2V, V2I, and V2P links according to embodiments of the present invention are depicted. Detailed Implementation

[0024] In embodiments of the present invention, when the vehicle's ignition is turned off, the determination of the hazard level of the vehicle's location is used to determine whether the C-V2X and GNSS circuits and associated software elements of the TCU should be turned on while the vehicle's ignition remains off.

[0025] The purpose of C-V2X is to transmit a vehicle's identifier, timestamp, location, heading, and speed, as well as other essential safety information, to surrounding vehicles, especially when it is out of sight, to improve road safety. In typical designs, when the vehicle's ignition is off, the vehicle's C-V2X (and GNSS) are also turned off.

[0026] However, when the vehicle's ignition is off, keeping C-V2X on may be preferable to turning it off. For example, a vehicle might experience some kind of trouble on the road, such as a mechanical problem preventing it from proceeding normally along its intended route. Simply turning off C-V2X without checking the actual road conditions could potentially be dangerous. When a vehicle is disabled in traffic, it is preferable to keep C-V2X on to automatically notify surrounding vehicles of its incapacity. In contrast, keeping C-V2X on has very limited value when the vehicle is parked at home, in a parking lot, or in an airport garage. Furthermore, operating C-V2X and GNSS involves keeping the C-V2X application processor on, which can consume more than 100 times more current than suspending the application processor and disconnecting the C-V2X modem and GNSS engine.

[0027] One concern regarding shutting down C-V2X and GNSS is that, because C-V2X obtains its timing and location information from GNSS, it takes time to transition from disconnected to operational mode, and a GNSS cold start can take up to 60 seconds if the GNSS signal is weak. Furthermore, since C-V2X is a mission-critical feature, it should be activated quickly when needed. One way to address this concern is to ask the vehicle's driver how long the car is expected to remain parked at that location to determine whether to completely shut down C-V2X and GNSS or place the feature in standby mode. For example, if the expected parking duration at the safe location is less than 20 minutes, C-V2X and GNSS can be configured to remain in standby mode for up to 20 minutes and can then be shut down once more than 20 minutes have elapsed. Such trips could include picking up milk at a nearby grocery store, mailing a package at the post office, dropping off a gift at a friend's house, or stopping for a fast food delivery. On the other hand, if the vehicle is expected to be parked at home for more than 4 hours, C-V2X and GNSS can be shut down when the ignition is off. This intelligence regarding how to handle C-V2X and GNSS in ignition-off mode can also be configured on a telematics server based on past addresses and average parking durations from the user's navigation system, and the configuration file can then be downloaded to the vehicle.

[0028] Vehicle batteries are a finite resource. When the vehicle is parked in a safe location, it is unnecessary for C-V2X and GNSS to consume the vehicle battery. In such cases, turning off C-V2X and GNSS reduces battery power consumption.

[0029] The intent of C-V2X's V2V and V2P is to help vehicles and pedestrians equipped with this feature know the position, speed, and direction of travel of surrounding vehicles, thereby improving road safety. Therefore, to do this, C-V2X can be turned off when the vehicle is in a safe location. The vehicle's TCU can check the vehicle's position via online (or offline) map services. The vehicle's position can be used to make better decisions about keeping the vehicle's C-V2X system engaged, which in turn results in improved driving safety. Improvements in managing C-V2X and GNSS when the vehicle's ignition is off lead to improved power management for the TCU.

[0030] Figure 1 An example operating environment for embodiments of the present invention is described. For example, in Figure 1 As shown, the first vehicle 102-1 transmits broadcast messages to multiple other vehicles 102-2 to 102-6 via C-V2X. As previously mentioned, C-V2X can operate in both device-to-network mode and device-to-device mode (i.e., vehicle-to-vehicle) without needing to connect to a cellular network via a cellular phone tower.

[0031] Figure 2 A schematic block diagram of a system according to an embodiment of the present invention is depicted. The TCU (Telematics Control Unit) 202 includes: a vehicle processor 206; an application microprocessor 208 in which C-V2X and other telematics applications are executed; a first cellular modem (for telematics services) 210; a second cellular modem 212 (for other infotainment services on a personal SIM, and potentially with an architecture that can be expanded to support more than two cellular radios up to N modems); a C-V2X (Vehicle-to-Everything) modem 214 (sometimes combined with the first cellular modem); and a GNSS (Global Navigation Satellite System) engine 216 that provides the vehicle's location.

[0032] The vehicle processor of the TCU typically receives the ignition on / off signal 204 via the vehicle's CAN (Controller Area Network) bus. The TCU receives power from the vehicle battery 218.

[0033] For telematics, in the absence of C-V2X, upon receiving an ignition-on signal, the application processor, cellular modem, and GNSS will be powered on. Upon receiving an ignition-off signal, the application processor and GNSS engine will suspend (i.e., enter power-saving mode to significantly reduce power consumption), and the cellular modem will remain powered on to receive incoming telematics service messages (e.g., door unlocking).

[0034] For telematics, in the case of C-V2X, upon receiving an ignition-on signal, the application processor 208 is powered on, the cellular modem 210 used by the telematics service is powered on, the C-V2X modem 214 is powered on, and the GNSS engine 216 is powered on. Other cellular modems are also powered on.

[0035] Some newer TCUs feature DSDA (Dual Standby Dual Active), which is essentially a combination of two RF transceiver modems. One modem is used by the telematics service, while the other is used by the vehicle user's SIM.

[0036] In such a system, when the vehicle ignition is turned off, the modem used for telematics services can remain on, while the RF transceiver modem used for the vehicle user's SIM can be turned off to reduce current consumption.

[0037] When the vehicle is determined to be in a safe location and the C-V2X modem is in standby mode, upon receiving an ignition disconnect signal, the application processor 208 suspends, the cellular modem 210 for telematics services remains powered on, other cellular modems are powered off, the C-V2X modem 214 remains powered on, and the GNSS engine is powered off, which causes the broadcast of the latest known location determined by the GNSS engine 216.

[0038] When the vehicle is determined to be in a safe position and the C-V2X modem 214 is in standby mode, upon receiving an ignition disconnect signal, the application processor 208 is suspended, the cellular modem used by the telematics service remains powered on, other cellular modems are powered off, the C-V2X modem 214 is powered off, and the GNSS engine 216 is powered off.

[0039] When the vehicle is determined to be in a dangerous position, upon receiving an ignition disconnect signal, the application processor 208 remains powered on, the cellular modem used by the telematics service remains powered on, other cellular modems are powered off, the C-V2X modem 214 remains powered on, and the GNSS engine 216 remains powered on. Figure 3 This is a flowchart depicting the process according to an embodiment of the invention. At 302, the vehicle ignition is depicted being shut off. At 304, the vehicle's location is determined. The GNSS engine periodically provides the TCU's location in longitude and latitude coordinates to the C-V2X application being executed by the application processor. The vehicle's location is then sent to a map service (either online using a telematics connection or V2N link, or offline). For example, in the case of an online OSRM (nearest) web service, a GET request is made to ' / / router.project-osrm.org / nearest / vl / driving / ' using longitude and latitude coordinates, and the response indicates whether the location is on a road. If the location is on a road, it is considered a dangerous location. The open-source router, or OSRM, is a C++ implementation of a high-performance routing engine for finding the shortest path in road networks. OSRM "nearest" finds the nearest road segment by calculating the point-to-line distance from the provided input coordinates.

[0040] As shown at 308, it is determined whether a vehicle is in a hazardous location. In this context, determining whether a vehicle is in a hazardous location can be based on whether the vehicle's hazard lights are on and / or the nature of the vehicle's location, including, but not limited to, whether the vehicle is parked at home, in a garage, or in a parking lot, or whether the vehicle is on or near a road with other vehicles traveling on it. Hazard warnings received through map services or C-V2X direct warnings from infrastructure (e.g., TIM (Driver Information Message)) and CAM (Cooperative Awareness Message) messages, as defined in the SAE J2735 and ETSI CAM / DENM standards, can also be used to determine whether a location is hazardous. Some examples include, but are not limited to, accident areas, traffic congestion ahead, weather condition warnings, slippery roads, pedestrians ahead, railway crossings, lane closures, road closures, roadworks, etc.

[0041] The timestamps, positions, headings, and speeds of remote vehicles received via C-V2X can be used to determine whether that vehicle poses a safety hazard to the local vehicle (i.e., the vehicle receiving information via C-V2X). For example, a hazardous location determination algorithm can be implemented as follows: For any long-range vehicle traveling at 7 mph or higher, and if its heading (based on the long-range vehicle BSM received by the local vehicle via C-V2X) is within the following calculations Within ±10% (or any other suitable value chosen by the system design): It is the straight direction from the remote vehicle to the local vehicle.

[0042] , These are the latitude and longitude coordinates used for long-distance vehicles. , It is the latitude and longitude used for local vehicles. It's the difference in longitude. The distance between the two vehicles can be estimated as in (Latitude increment between the two vehicles), R is the radius of the Earth.

[0043] By using the speed information of remote vehicles, it is possible to determine how long it will take for a remote vehicle to arrive near a local vehicle.

[0044] For example, when the speed is above 7 mph, the location of a local vehicle can be considered hazardous, also referred to herein as a dangerous location, if the calculated value of T is less than or equal to 40 seconds or any suitable duration designed for it. After ignition disconnection, once a scan of surrounding vehicles within a preset time period (e.g., 3 minutes) is completed, and if any remote vehicle scanned meets the criteria outlined above, the location can be determined as a dangerous location. The criteria mentioned above for determining whether a location is dangerous are exemplary and not intended to be restrictive. For example, such a determination can be made for any remote vehicle traveling at 5 mph or higher, or 3 mph or higher. Similarly, T can be less than or equal to 60 seconds, 80 seconds, or 120 seconds.

[0045] When a vehicle is determined to be in a dangerous location via a map service, the "yes" branch is followed from 308, and the C-V2X application, C-V2X modem, and GNSS engine remain on. However, C-V2X can optionally be set to transmit-only mode to reduce power consumption, as shown at 310.

[0046] When the map service determines that the local vehicle is not in a dangerous location, or when the map service is unable to determine whether the vehicle is in a dangerous location, the danger zone determination algorithm using C-V2X, as described in more detail above, is executed, as depicted at 314.

[0047] When the local vehicle is determined to be in a dangerous location via the danger zone determination algorithm, the "yes" branch is followed from 314, and the C-V2X application, C-V2X modem and GNSS engine remain on. However, C-V2X can optionally be set to transmit-only mode to reduce power consumption, as shown at 310.

[0048] When it is determined that the vehicle is not in a dangerous location, the "No" branch from 314 is followed, and a determination is made regarding whether other available hazard determination checks (such as the use of lidar, one or more onboard vehicle cameras, radar technology, etc.) indicate that the local vehicle's current location is a dangerous location. If yes, the "Yes" branch from 315 is followed, and the C-V2X application, C-V2X modem, and GNSS engine remain on, but C-V2X can optionally be set to transmit-only mode to reduce power consumption, as shown at 310.

[0049] Otherwise, follow the "No" branch from 315 and determine whether the vehicle is located at a known long-duration parking location, as shown in 312. Such known parking locations can include: at home, at work, in a parking garage, etc., for example, all known addresses from the driving history of the local vehicle's navigation system. Using the average parking duration of known addresses, the address can be labeled as a long (>4 hours) parking address or a short (<20 minutes) parking address. These are example values, as are the values ​​in the table below, and other suitable values ​​can also be used, such as greater than 2 hours, 1 hour, or 30 minutes for long parking durations; and less than 30 minutes, 1 hour, 2 hours, or 3 hours for short parking durations. Address 1 Average parking duration Home Long (>4 hours) Address 2 Average parking duration Workplace Long (>4 hours) ... Address n Average parking duration post office Short (<20 minutes)

[0050] When it is determined that the local vehicle is not located at a known long-term parking location, the "No" branch from 312 is followed, and the expected parking duration is obtained via user input or, if the address is known, can be determined based on historical average parking durations (326). For example, the mean, median, mode, or range can be determined based on a set of historical parking durations at the local vehicle's current location. According to embodiments of the invention, the expected parking duration can be manually set by asking the vehicle's driver via a vehicle user interface, such as via a touchscreen display, audio prompts, and voice recognition.

[0051] According to an embodiment of the present invention, when a user inputs the expected parking duration, the user can be provided with an option to mark the current parking location as a dangerous location, thereby disregarding the system's determination that the parking location is not a dangerous location.

[0052] When it is determined that the vehicle is in a known long-term parking location, following the "yes" branch from 312, the GNSS engine is shut down, the C-V2X modem is shut down, and the application processor is powered off or suspended, as shown at 324.

[0053] When the expected parking duration is determined to be a long duration (e.g., 4 hours or longer), following the "No" branch from 328, the GNSS engine is shut down, the C-V2X modem is shut down, and the application processor is powered off or suspended, as shown at 324.

[0054] When the expected parking duration is determined to be short (e.g., 30 minutes or less), follow the "yes" branch from 328. Before setting the timer (316) based on the expected parking duration, the C-V2X modem and GNSS engine can be placed in standby mode, which is a power-saving mode (330) during which the C-V2X modem and GNSS engine prepare to wake up faster than from a completely disconnected state.

[0055] Then, it is determined whether the ignition remains off, as shown at 320.

[0056] Then, it is determined whether the timer has expired, as shown at 318.

[0057] When it is determined that the timer has not expired, follow the "No" branch from 318, and then make another determination regarding whether the ignition remains off, as shown at 320, followed by another determination regarding whether the timer has expired, as shown at 318.

[0058] When it is determined that the ignition remains off, follow the "yes" branch from 320, and determine whether the timer has expired, as shown at 318.

[0059] When it is determined that the vehicle ignition has not been kept off, follow the "No" branch from 320, and the C-V2X application, C-V2X modem and GNSS engine are turned on, as shown at 322.

[0060] When it is determined that the vehicle ignition has been kept off, follow the "yes" branch from 320, and when it is determined that the timer has expired, follow the "yes" branch from 318, and the GNSS engine is shut down, the C-V2X modem is shut down, and the application processor is powered off or suspended, as shown at 324. Figure 4 This is a top view of a local vehicle, a remote vehicle, and a danger zone according to an embodiment of the present invention. The remote vehicle 402 is traveling toward the local vehicle 404, as indicated by the heading arrow 406. The generally conical danger zone 400 is depicted as having lateral boundaries diverging at an angle of 5 degrees from the heading 406 of the remote vehicle 402. The distance 408 between the remote vehicle and the local vehicle is shown. As mentioned above, the time it will take for the remote vehicle to reach the local vehicle can be calculated using a familiar formula, which can be expressed as distance 408 divided by the speed of the remote vehicle when the speed of the remote vehicle exceeds a predetermined speed (such as 5, 10, 15, 20, or 25 mph) and when the local vehicle is not moving.

[0061] Figure 5 The steps for determining a hazardous location according to an embodiment of the invention are described. A C-V2X scan timer is activated for a predetermined duration (such as, for example, a value of at least 1, 2, 3, 4, or 5 minutes).

[0062] The determination of whether the C-V2X scan timer has expired is made, as shown at 504. When the timer has expired, the danger location determination process terminates, as shown at 506, and follows the "No" branch from 314.

[0063] If the C-V2X scan timer has not expired, follow the "No" branch from 508 and determine whether the incoming C-V2X message queue is empty. If the C-V2X message queue is determined to be empty, follow the "Yes" branch from 508, and the process returns 504. If the C-V2X message queue is determined to be not empty, follow the "No" branch from 508, and retrieve the C-V2X message from the queue, as shown at 510.

[0064] Then, a determination is made based on the TIM message regarding whether local vehicles are in a danger zone. TIM (Driver Information Message) can be used to include various traffic conditions and "advanced driver" messages. It provides a means of informing the public about both events (traffic accidents) and pre-planned roadworks. TIM messages can be used to alert the public to severe weather conditions and other local or regional emergencies. It can also be used for various speed warnings, traffic signs, road conditions, and other general information.

[0065] When a local vehicle is determined to be in a danger zone based on a TIM message, following the "Yes" branch from 512, the C-V2X scan timer stops, as shown at 516, and the parking location of the local vehicle is determined to be a danger zone, as depicted at 518. The process then proceeds according to the TIM message from 512. Figure 3 The "Yes" branch in 314.

[0066] When it is determined based on the TIM message that the local vehicle is not in the danger zone, the "No" branch from 512 is followed, and a determination is made regarding whether the remote vehicle is in the danger zone of the local vehicle based on the BSM message and calculations based on the speed, heading, and distance of the remote vehicle 402 relative to the local vehicle 404.

[0067] When it is determined that the remote vehicle is within the danger zone of the local vehicle, following the "Yes" branch from 514, the C-V2X scan timer stops, as shown at 516, and the parking position of the local vehicle is determined to be a danger position, as depicted at 518, and the process then follows from... Figure 3 The "Yes" branch in 314.

[0068] When it is determined that the remote vehicle is not in the danger zone of the local vehicle, follow the "No" branch from 514, and determine whether the C-V2X scan timer has expired, as described in 508, which is discussed in more detail above.

[0069] Figure 6The arrival of C-V2X at the TCU (Telematics Processing Control Unit) according to an embodiment of the invention is depicted. Timeline 602 continues with the earlier C-V2X messages shown above and the later C-V2X messages shown below. TIM (e.g., weather warning) 604 and TIM (e.g., construction area) 612 are depicted together with BSMs 606, 608, and 610 corresponding to remote vehicles 1, 2, and n (where n can be any integer greater than 2) pushed into the remote vehicle FIFO (First-In-First-Out) queue.

[0070] Figure 7 This illustration shows a method by which a telematics control unit 704 forms and transmits a Basic Safety Message (BSM) via C-V2X, according to an embodiment of the present invention. GNSS (Global Navigation Satellite System) data is received from a GNSS constellation 702 by a GNSS engine 706. The GNSS engine forwards time, position, velocity, and heading information to a C-V2X application 708 being executed by an application processor. The BSM is received by a C-V2X modem 710, which can transmit C-V2X data via one or more of V2V 712, V2P 714, and V2I 716. In this manner, any vehicle with C-V2X capability can broadcast its time, position, velocity, and heading, regardless of whether the vehicle is a local or remote vehicle. When a local vehicle is stationary, its position, velocity, and heading do not change. Therefore, it does not need to rely on GNSS to form the BSM message.

[0071] Figure 8 PC5 V2V, V2I, and V2P links according to embodiments of the present invention are depicted. PC5 V2V link 806 is shown between vehicles 802 and 810. PC5 V2I link 808 is shown between roadside unit 804 and vehicle 810. PC5 V2P link 812 is shown between pedestrian 814 and vehicle 810. The PC5 link is a C-V2X direct communication interface, similar to DSRC, and enables direct communication between local vehicles and other vehicles, roadside units, and pedestrians without the use of cellular networks.

[0072] While the invention has been described by way of various embodiments, and while these embodiments have been described in considerable detail, the applicant does not intend to limit the scope of the appended claims or restrict them in any way to such details. Additional advantages and modifications will readily become apparent to those skilled in the art. The invention, in its broader aspects, is therefore not limited to the specific details, representative devices and methods, and the illustrative examples shown and described. Thus, deviations from such details may be made without departing from the spirit or scope of the applicant's general inventive concept.

Claims

1. A method executed by a telematics control unit of a parked motor vehicle, the method comprising: Determine whether the ignition of the parked vehicle is off; Determine whether parked motor vehicles are located in dangerous positions; When a parked vehicle is determined to be in a dangerous location, the cellular vehicle-to-everything (C-V2X) modem of the parked vehicle and the global navigation satellite system (GNSS) engine of the parked vehicle are connected to increase safety by allowing the C-V2X modem to continue transmitting C-V2X messages, relative to turning off the C-V2X modem. When it is determined that the parked motor vehicle is located in a location that is not dangerous, determine whether the parked motor vehicle is located in a known long-term parking location; as well as When the vehicle is located in a known long-term parking position, both the GNSS engine and the C-V2X modem are turned off to reduce battery power consumption compared to keeping both the GNSS engine and the C-V2X modem on.

2. The method of claim 1, wherein determining whether a parked motor vehicle is located in a dangerous position further comprises: Send the location of parked vehicles to the map service.

3. The method of claim 2, wherein the map service is an open-source router.

4. The method of claim 1, wherein when it is determined that the parked motor vehicle is not located at a known long parking location, the expected parking duration is obtained.

5. The method of claim 4, wherein the expected parking duration is obtained via user input.

6. The method of claim 4, wherein the expected parking duration is determined based on the historical average parking duration of vehicles parked there.

7. The method of claim 4, wherein when the acquired parking duration is not less than 20 minutes, both the GNSS engine and the C-V2X modem are shut off to reduce battery power consumption relative to keeping both the GNSS engine and the C-V2X modem on.

8. The method of claim 4, wherein when the acquired parking duration is less than 20 minutes, both the C-V2X modem and the GNSS engine are placed in standby mode to reduce battery power consumption relative to turning on both the C-V2X modem and the GNSS engine.

9. The method of claim 8, further comprising: Set and activate the timer, and when the timer expires, shut down both the GNSS engine and the C-V2X modem to reduce battery power consumption compared to putting both the C-V2X modem and the GNSS engine into standby mode.

10. A motor vehicle telematics control unit (TCU), comprising: The TCU application processor is coupled to the vehicle processor, the Global Navigation Satellite System (GNSS) engine, multiple cellular modems, and the Cellular Vehicle-to-Everything (C-V2X) modem, wherein the TCU application processor is configured as follows: Determine whether the ignition of the parked vehicle is off; Determine whether parked motor vehicles are located in dangerous positions; When a parked vehicle is determined to be in a dangerous location, both the C-V2X modem and the GNSS engine of the parked vehicle are connected to increase safety by allowing the C-V2X modem to continue transmitting C-V2X messages, compared to turning off the C-V2X modem. When it is determined that the parked motor vehicle is located in a location that is not dangerous, determine whether the parked motor vehicle is located in a known long-term parking location; as well as When the vehicle is located in a known long-term parking position, both the GNSS engine and the C-V2X modem are turned off to reduce battery power consumption compared to keeping both the GNSS engine and the C-V2X modem on.

11. The motor vehicle TCU of claim 10, wherein determining whether a parked motor vehicle is located in a dangerous position further includes: Send the location of parked vehicles to the map service.

12. The motor vehicle TCU as described in claim 11, wherein the map service is an open-source router.

13. The motor vehicle TCU of claim 10, wherein when it is determined that the parked motor vehicle is not located at a known long parking location, the expected parking duration is obtained.

14. The motor vehicle TCU of claim 13, wherein the expected parking duration is obtained via user input.

15. The motor vehicle TCU of claim 13, wherein the expected parking duration is determined based on the historical average parking duration of vehicles parked there.

16. The motor vehicle TCU of claim 13, wherein when the acquired parking duration is not less than 20 minutes, both the GNSS engine and the C-V2X modem are shut down to reduce battery power consumption relative to turning on both the GNSS engine and the C-V2X modem.

17. The motor vehicle TCU of claim 13, wherein when the acquired parking duration is less than 20 minutes, both the C-V2X modem and the GNSS engine are placed in standby mode to reduce battery power consumption relative to turning on both the C-V2X modem and the GNSS engine.

18. The motor vehicle TCU as described in claim 17, further comprising: Set and activate the timer, and when the timer expires, shut down both the GNSS engine and the C-V2X modem to reduce battery power consumption compared to putting both the C-V2X modem and the GNSS engine into standby mode.

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