Method and device for communication in a cooperative intelligent transport system

Abstract

In an Intelligent Transport System, ITS, the occupancy status of a parking spot by a mobile object is determined based on description information related to the mobile object obtained from at least on

Description

The present invention generally relates to Cooperative Intelligent Transport Systems (C-ITS), and more specifically to methods and devices for exchanging parking information about parking spots among ITS stations (ITS-Ss). BACKGROUND OF THE INVENTION Cooperative Intelligent Transport Systems (C-ITS) aim to enhance road safety, traffic efficiency, and the overall driver experience. While primarily associated with road transport, C-ITS services extend beyond this scope. Broadly, C-ITS can be defined as the application of information and communication technologies (ICT) across rail, water, and airtransport, including navigation systems. These diverse C-ITS implementations typically rely on radio services for communication and employ specialized technologies. C-ITS are governed by standards specific to each country or territory where they are deployed. In Europe, the European Telecommunications Standards Institute is currently responsible for developing the specifications that form the standards governing C-ITS. Cooperation within C-ITS is achieved through the exchange of messages, known as ITS messages, among ITS stations (denoted as ITS-Ss). ITS-Ss can include vehicles, Roadside Units (RSUs), Vulnerable Road Users (VRUs) carrying ITS equipment (such as smartphones, GPS devices, smartwatches, or cyclist gear), as well as any other entities or infrastructures equipped with ITS technology. This also encompasses central subsystems like back-end systems and traffic management centres. C-ITS can support various types of communication, such as vehicle-to-vehicle (V2V), which applies to all types of road users, for example, car-to-car communication. They also support communication between vehicles and fixed locations, known as vehicle-to-infrastructure (V2I) and infrastructure-to-vehicle (I2V), such as car-to-infrastructure communication. These message exchanges are typically conducted over wireless networks. Examples of these technologies include 3GPP LTE-Advanced Pro, 3GPP 5G, or IEEE 802.11p. Exemplary ITS messages include, without limitation, Collective Perception Messages (CPMs), Cooperative Awareness Messages (CAMs), and Decentralized Environmental Notification Messages (DENMs). The ITS station (ITS-S) that sends an ITS message is referred to as the 'originating' ITS-S, while the ITS-S that receives the message is referred to as the 'receiving' ITS-S. ETSI TS 103 324 (v2.1.1, 2023) defines the Collective Perception Service, which enables an ITS-S equipped with on-board sensor systems to detect objects in its vicinity and transmit descriptive information (e.g., dynamics such as position and / or kinematic data) using broadcast CPMs. These messages are sent periodically, with intervals ranging from 100 ms to 1 second, depending on several factors such as the speed of the objects detected by the originating ITS-S. ETSI TS 103 900 (V2.1.1, 2023) defines the Cooperative Awareness Basic Service, through which an ITS-S broadcasts its ego-vehicle dynamics (e.g., position and speed) using CAMs. Similarly, ETSI TS 103 300-3 (V2.2.1, February 2023) defines the Vulnerable Road User (VRU) Awareness Basic Service, where an ITS-S corresponding to a VRU (e.g., a pedestrian) transmits its ego-position, speed, and the type of VRU, using Vulnerable Road User Awareness Messages (VAMs). ETSI TS 103 831 (V2.2.1,2024) defines the Decentralized Environmental Notification Basic Service, which allows an originating ITS-S to broadcast DENMs, such as warnings or alerts, to other ITS-Ss. These messages notify events detected by the originating ITS-S, such as road hazards, changes in driving conditions, or traffic issues. ETSI TS 103 301 (V2.1.1, 2021) defines messages for infrastructure-to-vehicle communication, such as SPATEM / MAPEM, used to signal traffic light phases, timing, and road topology. Additional ITS messages, known as Manoeuvre Coordination Messages (MCMs), are currently being specified to facilitate coordination among automated vehicles. These messages provide a protocol for automated vehicles to negotiate trajectories or reserve space and time on the road for specific manoeuvres, such as lane changes or merging. MCMs can be exchanged between vehicles to negotiate manoeuvres, and infrastructure-based systems like Roadside Units (RSUs) can also be involved in coordinating these manoeuvres. A manoeuvre request can be initiated by either a vehicle or an infrastructure-based system. ETSI TS 103 916 (V2.1.1, 2024) defines the Parking Availability Service (PAS), which enables an ITS-S to broadcast information about the status of parking places and individual parking spaces. This information is contained in a Parking Availability Message (POIM-PA), comprising generic Points of Interest (POI) information blocks and specific Parking Availability information blocks. This message is intended to be broadcast by a roadside unit or a central station managing a parking place. ETSI TS 104 072, Cooperative Parking Occupancy Distribution and Assignment Service (PODAS), plans to extend the Parking Availability Service to include parking information provided by vehicular ITS-Ss. This service will encompass parking spot occupancy details and reservation information. It will describe one or more messages, currently provisioned as a Parking Occupancy Distribution and Assignment (POAMM), for disseminating information about available parking spots and for indicating a parking spot allocated to a specific ITS-S. Determining the occupancy status of parking spots is essential for efficient parking management. According to current state-of-the-art techniques, this can be achieved through sensors on vehicles, which provide real-time data as they drive through areas, or through sensors installed in parking infrastructure, which offer consistent monitoring of parking spaces. Determining the occupancy status of a parking spot using sensors equipped on vehicles or infrastructure involves leveraging advanced technologies to monitor and report whether parking spaces are occupied or available. In the vehicle-based approach, sensors such as cameras, radar, and ultrasonic devices installed on vehicles can detect the status of parking spots as vehicles traverse different areas. These sensors collect real-time data about parking space occupancy, providing dynamic and widespread coverage. However, this method has its limitations, including potential coverage gaps in less-travelled areas, difficulties in detecting small or obstructed parking spaces, and variations in data accuracy due to factors like vehicle speed, weather conditions, and lighting. Privacy concerns may also arise, as vehicle sensors could potentially track individual vehicles or their movements. Additionally, the effectiveness of this approach relies on a significant number of vehicles being equipped with the necessary sensors. Conversely, infrastructure-based sensors are installed in fixed locations, such as within the pavement of parking lots or on street signs. These sensors offer a stable and consistent means of measuring parking space occupancy, ensuring comprehensive coverage within their installation area. They generally present fewer privacy issues, as they do not track individual vehicles. Nonetheless, this approach also has drawbacks, including the high costs of installation and maintenance, limited scope confined to the area covered by the infrastructure, and potential delays in data collection and transmission. Infrastructure-based sensors can also be vulnerable to vandalism and damage, and maintaining power and connectivity in outdoor or remote locations can be challenging. Thus, there is a need for an improved method of determining and sharing the occupancy status of parking spots that overcomes the drawbacks of current state-of-the-art techniques. SUMMARY In accordance with a first aspect of the invention, there is provided a method of communication in an Intelligent Transport System, ITS, including a plurality of ITS stations, ITS-Ss, the method at a receiving ITS-S of the plurality of ITS-Ss comprising: determining an occupancy status of a parking spot by a mobile object, based on description information related to the mobile object obtained from at least one ITS message, the description information comprising status information, including a position of the mobile object, and reporting information about the mobile object. Accordingly, by relying on ITS messages, the embodiments of the present invention may not require specific modifications or additional hardware to be implemented in an ITS system to determine the occupancy status of parking spots, particularly eliminating the need for dedicated sensors as required by current state-of-the-art techniques. In some embodiments, at least part of the description information may be obtained from at least one CAM message disseminating information about the mobile object as a host object. In some embodiments, at least part of the description information may be obtained from CPM messages disseminating information about the mobile object as a perceived object. In some embodiments, at least part of the description information may be obtained from a MCM message disseminating information about the mobile object as being part of a manoeuvre coordination. In some embodiments, the reporting information may indicate the start or end of a silent period during which no CAM messages are sent by an originating ITS-S equipping the mobile object. In some embodiments, the reporting information may indicate that a silent period during which no CAM messages are sent by an originating ITS-S equipping the mobile object has started or has expired. In some embodiments, determining, as occupied, the occupancy status of the parking spot by the mobile object may comprise determining that the position of the mobile object is within or substantially close to the parking spot, and determining that the reporting information indicates the start of the silent period or is indicative that the silent period has started. In some embodiments, determining, as available, the occupancy status of the parking spot by the mobile object may comprise determining that the position of the mobile object is within or substantially close to the parking spot, and determining that the reporting information indicates the end of the silent period or is indicative that the silent period has expired. In some embodiments, the reporting information may indicate a change in a mobility status of the mobile object, either from a static object to a moving object or from a moving object to a static object. In some embodiments, determining, as occupied, the occupancy status of the parking spot by the mobile object may comprise determining that the position of the mobile object is within or substantially close to the parking spot, and determining that the reporting information indicates a change in the mobility status of the mobile object from a moving object to a static object. In some embodiments, determining, as available, the occupancy status of the parking spot by the mobile object may comprise determining that the position of the mobile object is within or substantially close to the parking spot, and determining that the reporting information indicates a change in the mobility status of the mobile object from a static object to a moving object. In some embodiments, the reporting information may indicate that the manoeuvre coordination for the mobile object starts at a parking spot, or may indicate that the manoeuvre coordination for the mobile object ends at a parking spot. In some embodiments, determining, as 'about to be occupied', the occupancy status of the parking spot by the mobile object may comprise determining that the reporting information indicates that the manoeuvre coordination for the mobile object ends at the parking spot, and determining, as occupied, the occupancy status of the parking spot by the mobile object may further comprise determining that the required time to complete the manoeuvre has elapsed. In some embodiments, determining, as 'about to be available', the occupancy status of the parking spot by the mobile object may comprise determining that the reporting information indicates that the manoeuvre coordination for the mobile object starts at the parking spot, and determining, as available, the occupancy status of the parking spot by the mobile object may further comprise determining that the required time to complete the manoeuvre has elapsed. In some embodiments, the method may further comprise sending an ITS message including parking information related to the parking spot, the parking information including the determined occupancy status. In some embodiments, sending an ITS message including parking information may comprise sending an ITS message including parking information upon detecting a triggering condition, and the triggering condition may be at least one of: o The elapsed time since the determining of the occupancy status is higher than a predefined check period, while the determined occupancy status remains unchanged; o The distance between a current position of the mobile object and the parking spot is less than a first distance threshold, respectively greater than a second distance threshold, for a determined occupied status, respectively for a determined available status. In some embodiments, the step of determining an occupancy status of a parking spot by a mobile object may be carried out in response to receiving a request for determining the occupancy status of the parking spot. In accordance with a second aspect of the invention, there is provided a processing device configured to perform the method according to any aspect or embodiment described above. Any feature in one aspect of the invention may be applied to other aspects of the invention, in any appropriate combination. In particular, method aspects may be applied to apparatus / device / unit aspects, and vice versa. Furthermore, features implemented in hardware may be implemented in software, and vice versa. Any reference to software and hardware features herein should be construed accordingly. For example, in accordance with other aspects of the invention, there are provided a computer program comprising instructions which, when the program is executed by a processing unit, cause the processing unit to carry out the method of any aspect or example described above and a computer readable storage medium carrying the computer program. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention will now be described, byway of example only, and with reference to the following drawings in which: Figure 1 illustrates an example of an ITS in which embodiments of the invention may be implemented, Figure 2 is a flowchart of a method for determining the occupancy status of a parking spot by a mobile object, according to embodiments of the invention, Figure 3 is flowchart of a method for determining the occupancy status of a parking spot by a mobile object, according to other embodiments of the invention, Figure 4 is a flowchart of a method for using the occupancy status of a parking spot for parking operations when broadcast in an ITS message, according to embodiments of the invention, Figure 5 is a flowchart of a method for sharing the occupancy status of a parking spot, by an originating ITS station equipping a vehicle (mobile object) that is about to leave the parking spot, according to embodiments of the invention, Figure 6 is a flowchart illustrating a method for a receiving ITS station to respond to a parking spot information request sent by an originating ITS station, according to embodiments of the invention, Figure 7 illustrates the structure of an enhanced CAM message, according to embodiments of the invention, Figure 8 illustrates the structure of an enhanced MCM message, according to embodiments of the invention, Figure 9 illustrates the structure of an enhanced PODAM message, according to embodiments of the invention, and Figure 10 shows the hardware structure of an ITS station, in which the invention may be implemented. DETAILED DESCRIPTION OF EMBODIMENTS Embodiments of the present invention provide methods, devices and computer program products for determining and sharing the occupancy status of a parking spot by a mobile object, such as a vehicle, by leveraging ITS (Intelligent Transport System) messages sent in a broadcast or unicast manner, eliminating the need for dedicated sensors as required in the current state-of-the-art techniques. To accomplish this, two types of information about the mobile object, obtained from the ITS messages, are used: status information that describes details intrinsically related to the mobile object itself, such as its position and speed, and reporting information that describes how the mobile object is reported within the ITS messages, such as its reporting frequency. The embodiments of the invention are not limited to a specific type of ITS message, as various ITS messages can be used to obtain each of the two types of information, or any of the types of information. For example, status information may be obtained using a first type of ITS message, while reporting information is obtained using a second type of ITS message. Alternatively, status information and reporting information may both be obtained using both the first and second types of ITS messages. By relying on standardized ITS messages, the embodiments of the present invention may not require specific modifications or additional hardware to be implemented in an ITS system. Methods, devices, and computer program products according to the various embodiments of the invention can be implemented in any ITS system where ITS messages are exchanged between ITS stations to share perception data. This perception data may relate to either the originating ITS station and / or its surrounding environment. The ITS system may be a terrestrial ITS system that is designed to improve the safety, efficiency, and management of ground transportation networks. It utilizes a range of technologies, including sensors, cameras, and communication devices, installed on roads and vehicles to monitor and manage traffic conditions in real-time. Key applications include adaptive traffic signal control, real-time traffic updates, and vehicle-to-infrastructure communication. Terrestrial ITS systems aim to optimize traffic flow, reduce congestion, enhance road safety, and support smart city initiatives by integrating with other urban infrastructure. The ITS system may be a water ITS system that focuses on enhancing maritime transportation through advanced technology and communication networks. This system employs sensors, radar, and GPS to monitor and manage vessel movements, navigation, and environmental conditions on the water. It facilitates real-time communication between ships and shore-based control centres, supporting applications such as collision avoidance, port traffic management, and environmental monitoring. Water ITS systems aim to improve maritime safety, operational efficiency, and environmental protection by providing better situational awareness and coordination. The ITS system may be an aerial ITS system that is designed to optimize air traffic management and enhance the safety and efficiency of aviation operations. This system uses advanced technologies such as radar, satellite communication, and data analytics to monitor aircraft movements, manage air traffic, and ensure safe and efficient flight operations. Key applications include air traffic control, aircraft collision avoidance, and real-time weather updates. Aerial ITS systems aim to improve air traffic flow, reduce delays, and enhance safety in increasingly congested airspace. For illustration purposes only, the following description will refer to a terrestrial ITS system comprising multiple ITS stations installed on roads, vehicles, and vulnerable ITS users to share perception data through ITS messages, with parking spots available for mobile objects such as vehicles, trucks, motorcycles, or bicycles. However, it will be readily understood by those skilled in the art that the various embodiments of the invention may apply to other types of ITS systems. Generally, the invention may be integrated into any ITS system where parking spots are available for mobile objects to be parked, whether temporarily or for longer durations. In the following description, the expression ‘ITS message’ is used to designate any communication or data packet exchanged within an ITS network. This encompasses a variety of message types, including those used for vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), and vehicle-to-everything (V2X) communications. ITS messages carry essential information such as vehicle status, perceived object, sensor data, traffic conditions, and safety alerts, facilitating real-time decision-making and coordination among ITS stations. These messages are crucial for ensuring the smooth operation and safety of the transportation system, enabling efficient data sharing and interaction across the network. In the context of the ETSI (European Telecommunications Standards Institute) standards, ITS messages encompass a variety of communication types that facilitate different aspects of intelligent transport systems. Examples of ITS messages that are compatible with embodiments of the invention include, but are not limited to: 1. CPM (Collective Perception Message): CPMs are used to share information about the environment as perceived by the sensors of an ITS station, typically a vehicle. These messages include data about detected objects, such as other vehicles, pedestrians, or obstacles, that are within the sensor's range. CPMs enhance situational awareness by allowing vehicles and infrastructure to "see" beyond their line of sight, thereby improving safety and enabling advanced cooperative driving functions. 2. CAM (Cooperative Awareness Message): CAMs are periodically sent by vehicles to broadcast their current status, including position, speed, heading, and other dynamic data. These messages are fundamental for creating a cooperative environment where vehicles and infrastructure can maintain real-time awareness of each other's presence and movement. CAMs are essential for applications like lane change assistance, adaptive cruise control, and collision avoidance. 3. MCM (Mobility Cooperation Message): MCMs are used to support cooperative manoeuvres between vehicles, such as lane changes, merging, or platooning. These messages convey information about a vehicle's intended actions and its willingness to cooperate with other vehicles. MCMs help facilitate smooth, coordinated manoeuvres in complex traffic scenarios, improving traffic flow and reducing the risk of collisions. 4. DENM (Decentralized Environmental Notification Message): DENMs are event-triggered messages that inform nearby vehicles and infrastructure about specific incidents or hazards, such as accidents, roadworks, or slippery roads. These messages are critical for alerting road users to unexpected events and enabling timely responses, thereby enhancing road safety. 5. PODAM (Parking Occupancy Distribution and Assignment Message): PODAMs are intended for disseminating information about available parking spaces in real-time and to describe the specific parking spot allocated to a particular ITS station. These messages help drivers locate free spots more efficiently, reducing the time spent searching for parking and they also provide precise information to ensure accurate parking assignments, streamlining the allocation process and helping manage parking resources effectively. 6. POM (Parking Occupancy Message): POMs are intended for disseminating information about available parking spaces in real-time. These messages help drivers locate free spots more efficiently, reducing the time spent searching for parking. A POM is a possible restricted version of a PODAM. 7. PAIM (Parking Assignment Indication Message): PAIMs are intended to describe the specific parking spot allocated to a particular ITS station. These messages provide precise information to ensure accurate parking assignments, streamlining the allocation process and helping manage parking resources effectively. A PAIM is a possible restricted version of a PODAM. In the following description, the expression 'enhanced ITS message' is used to designate an ITS message that retains the structure of a respective basic ITS message, such as CPM, CAM, or MCM, while incorporating one or more additional data elements. The one or more additional data elements are proposed according to embodiments of the invention to facilitate the easy determination of the occupancy status of a parking spot by a mobile object. For example, an enhanced CAM message retains the structure of a basic CAM message according to ETSI standards while incorporating one or more additional data elements. In the following description, the expression 'mobile object' is used to designate any object capable of moving and occupying a parking spot temporarily or long-term. Examples of mobile objects include, but are not limited to, vehicles, motorcycles, trucks, and bicycles. The mobile object may be either connected, equipped with an ITS station configured to transmit and / or receive ITS messages, or unconnected. In both cases, the mobile object can be detected and reported by other ITS stations, whether they are mounted on other mobile objects or roadside units. In the following description, the expression 'parking spot' and 'parking place' are used interchangeably to designate a specific area where mobile objects, such as vehicles, can be parked. Both terms refer to a specific location intended for the temporary or long-term accommodation of mobile objects, whether on public or private property. This could include spaces within parking lots, on-street parking areas, or other designated zones intended to facilitate organized vehicle storage. In the following description, the expression 'occupancy status' refers to the condition of a parking spot, specifically indicating whether it is currently occupied or available. For example, a parking spot may be declared as occupied if a moving object remains within it for at least a predefined time threshold. Conversely, the parking spot may be declared as available if no moving object is present within it for another predefined time threshold. According to the invention, the occupancy status of a parking spot may not be limited to occupied and available but may include other statuses. For example, a parking spot may be declared as 'about to be occupied' or 'likely to be occupied' if it is determined that a mobile object is approaching the parking spot. Conversely, the parking spot may be declared as 'about to be available' or 'likely to be available' if it is determined that a mobile object is leaving the parking spot. Of course, the occupancy status may include additional attributes that provide more detailed information about the parking spot. For example, the additional attributes may specify the size of the parking spot or other relevant characteristics, offering a more comprehensive view of its availability and suitability for different types of mobile objects. Figure 1 illustrates an example of an ITS 100 in which embodiments of the invention may be implemented. The ITS is integrated into road infrastructure that includes a parking lot with multiple parking spaces intended for the parking of mobile objects, such as vehicles or motorcycles. The ITS comprises multiple ITS stations capable of transmitting and / or receiving ITS messages. Typically, an ITS message is broadcast, allowing all ITS stations within the communication range of the originating station to receive it. Of course, some types of ITS messages may be sent in a unicast manner. Generally, ITS stations can be categorized based on several factors, including their mobility status and the types of ITS messages they generate. Depending on mobility status, an ITS station may be installed on a mobile object, such as a vehicle, or embedded within a fixed roadside unit. In terms of message types, one ITS station may be authorized to send only CAM messages, while another ITS station may be limited to sending CPM messages. Furthermore, users and objects within the road infrastructure can participate in the ITS either actively or passively. Active participation occurs when users or objects process ITS messages through dedicated ITS stations with which they are equipped. Passive participation, on the other hand, involves users or objects being detected and reported as perceived objects by other ITS stations within the ITS. Figure 1 illustrates four communication scenarios that highlight the benefits of the invention in determining the occupancy status of a parking slot using only broadcast ITS messages. In these four communication scenarios, the mobiles objects are vehicles and the ITS messages are broadcast. In the first communication scenario, which utilizes CAM messages, the vehicle V101 is equipped with an ITS station that sends CAM messages detailing the vehicle's current status, including its position, speed, heading, and other dynamic data. Typically, CAM messages are transmitted only when the vehicle is started (e.g., the engine is running or the vehicle is powered up), regardless of whether the vehicle is stationary or in motion. In addition, CAM messages are broadcast periodically from a vehicle to other vehicles and infrastructure within its communication range, with a typical reporting frequency of 1 Hz. The vehicle V102, acting as a receiving ITS station, is located within the communication range of vehicle V101 and may be configured, according to embodiments of the invention, to receive a CAM message from vehicle V101 and determine that this CAM message was sent following a silent period during which no CAM messages were transmitted by vehicle V101. This determination may be made based on the CAM reporting frequency and the elapsed time since vehicle V102 entered the communication range of vehicle V101. Following this determination, vehicle V102 may infer that vehicle V101 was parked and that the parking spot it occupied is about to be available, based on the position of vehicle V101 and the fact that this position corresponds to a parking spot. Vehicle V102 may further await another CAM message indicating that vehicle V101 is moving away from the parking spot before declaring the occupancy status of the parking spot as available. Vehicle V102 may also use the determined occupancy status of the parking spot for a parking operation or share it with other ITS stations within its communication range. In the second communication scenario, which relies on CPM messages, the roadside unit R101 is equipped with multiple sensors designed to perceive its surrounding environment. The roadside unit R101 also includes an ITS station that sends CPM messages containing data about detected objects, such as other vehicles, pedestrians, or obstacles, within the sensors' range. Among the detected objects is vehicle V103, which is not equipped with an ITS station and, therefore, cannot send or receive ITS messages. Typically, an object may be reported, using CPM messages, immediately upon initial detection to ensure that all relevant ITS stations are aware of its presence. After the initial report, updates, using CPM messages, on static objects are typically sent at longer intervals compared to dynamic objects. The interval may range from several seconds to minutes, depending on the object's relevance and the surrounding context. If the position of a static object changes (e.g., a parked vehicle starts moving), it may trigger an immediate update to alert other ITS stations. The vehicle V104, acting as a receiving ITS station, is located within the communication range of the roadside unit R101 and may be configured, according to embodiments of the invention, to receive one or more CPM messages from the roadside unit R101 and determine a change in the mobility status of vehicle V103, whether from a static vehicle to a moving vehicle (example illustrated in Figure 1) or vice versa. For example, the determination may involve analysing the reporting frequency of vehicle V103 as a perceived object within successive CPM messages, assuming that a moving object is reported at a higher frequency than a static object. Based on the position of vehicle V103 associated with its static behaviour, and the fact that this position corresponds to a parking spot, vehicle V104 may infer whether vehicle V103 has left or entered the parking spot, depending on whether its mobility status has changed from static to mobile or from mobile to static, respectively. Vehicle V104 may further await other CPM messages confirming the lastly determined mobility status before declaring the occupancy status of the parking spot as available or occupied. Vehicle V104 may also use the determined occupancy status of the parking spot for a parking operation or share it with other ITS stations within its communication range. In the third communication scenario using MCM messages, the vehicle V105 is equipped with an ITS station used to send MCM messages to support cooperative manoeuvres between vehicles. MCM messages often include trajectory information, which describes the path that the vehicle intends to follow over a certain period. This may include details like the intended lane, speed, and timing of the manoeuvre. The vehicle V106, acting as a receiving ITS station, is located within the communication range of vehicle V105 and may be configured, according to embodiments of the invention, to receive an MCM message, including a declared trajectory, from vehicle V105 and determine whether the starting point or endpoint (example illustrated in Figure 1) of the declared trajectory correspond to a parking spot. Following this determination, vehicle V106 may infer that the parking spot corresponding to the starting point is, for example, 'about to be available', while the parking spot corresponding to the endpoint is, for example, 'about to be occupied'. Vehicle V106 may also use the determined occupancy statuses of the parking spots for a parking operation or share them with other ITS stations within its communication range. In the fourth communication scenario, which combines MCM, CAM, and CPM messages, vehicle V107 is equipped with an ITS station that sends CAM messages to share the vehicle's current status and MCM messages to support cooperative manoeuvres between vehicles. Additionally, vehicle V107 may be detected and reported by a CPM-originating ITS station, such as the one equipped on roadside unit R102. The vehicle V108, acting as a receiving ITS station, is located within the communication range of both vehicle V107 and the roadside unit R102, and may be configured, according to embodiments of the invention, to receive an MCM message, including a declared trajectory, from vehicle V107 and determine that the endpoint of the declared trajectory corresponds to a parking spot. Following this first determination, vehicle V108 may infer that the parking spot corresponding to the endpoint is, for example, about to be occupied. Vehicle V108 may also be configured, according to embodiments of the invention, to receive a CAM message from vehicle V107 and determine that this CAM message is sent before a silent period during which no CAM messages will be transmitted by vehicle V107, while indicating that the position ofvehicle V107 corresponds to the parking spot. Following this second determination, vehicle V108 may infer that the parking spot has just been occupied. Additionally, vehicle V108 may be configured, according to embodiments of the invention, to receive one or more CPM messages from roadside unit R102 that report vehicle V107 as a static object, while indicating that the position ofvehicle V107 corresponds to the parking spot. Following this third determination, vehicle V108 may infer that the parking spot is occupied. Vehicle V108 may also use the determined occupancy statuses of the parking spot for a parking operation or share them with other ITS stations within its communication range. Figure 2 is a flowchart of a method 200 for determining the occupancy status of a parking spot by a mobile object, according to embodiments of the invention. The occupancy status is one of a list of possible statuses, including at least occupied and available. According to the invention, the occupied status is assigned to the parking spot if the parking spot is occupied by the mobile object, whereas the available status is assigned to the parking spot if the mobile object is not in the parking spot. A specific case where the available status is assigned to the parking spot is when the mobile object has left the parking spot. Of course, the list of possible statuses may include other statuses. The method of Figure 2 may be implemented in any processing device with the necessary resources to use description information about the mobile object obtained from one or more ITS messages to carry out a method, according to embodiments of the invention, for determining the occupancy status of the parking spot. For example, the processing device may be part of an ITS station capable of receiving and properly decoding ITS messages sent within its communication range. Alternatively, the processing device may be part of, or embedded within, a remote control centre capable of receiving description information about the mobile object obtained from ITS messages to determine the occupancy status of the parking spot. Additionally, the processing device may be hosted on a cloud computing platform, where it processes description information about the mobile object obtained from ITS stations to determine the occupancy status of the parking spot. At step S210, description information related to the mobile object is obtained from one or more ITS messages. This description information includes both status information and reporting information. The status information describes details intrinsically related to the mobile object itself, such as its position and speed, while the reporting information describes how the mobile object is reported within the ITS messages, such as its reporting frequency. Generally, the interpretation of the status information may be made regardless of the types of ITS messages from which it is obtained, whereas the interpretation of the reporting information may need to be correlated with the types of ITS messages from which it is obtained. The status information includes the position of the mobile object, and if multiple positions are provided across different ITS messages, only the most recent position may be considered or the multiple positions may be merged into a single position. The reporting information may include information elements explicitly contained in the ITS messages, as well as information elements derived from the ITS messages. The reporting frequency is an example of an information element derived from the ITS messages, as it is determined by analysing which consecutive ITS messages report on the mobile object. The absence of one or more ITS messages reporting on the mobile object is another example of an information element derived from the ITS messages. The embodiments of the invention are not limited to a specific type of ITS message, as various ITS messages can be used to obtain each of the two types of information, or any of the types of information. For example, status information may be obtained using a first type of ITS message, while reporting information is obtained using a second type of ITS message. Alternatively, status information and reporting information may both be obtained using both the first and second types of ITS messages. Generally, reporting information elements may be obtained from ITS messages that include status information elements, whereas status information elements may not be obtained from ITS messages from which reporting information elements are derived. Preferably, the one or more ITS messages from which the description information is obtained are sent within an analysis period that is shorter than a predetermined analysis period threshold. In some embodiments, the one or more ITS messages from which the description information is obtained are sent by the same originating ITS station, such as an ITS station equipping the mobile object itself, another mobile object, or a roadside unit. Additionally, the ITS messages may be of the same type, such as CAM messages, or of various types, such as CAM and CPM messages. In fact, depending on the authorizations granted by an Authorization Authority (AA) in an ITS, the originating ITS station may be permitted to send different types of ITS messages. Of course, at least one type of ITS message provides the position of the mobile object. In other embodiments, the description information is obtained from ITS messages sent by multiple originating ITS stations, which may include ITS stations equipping the mobile object itself, another mobile object, and / or a roadside unit. These ITS messages may be of the same type, such as CAM messages, or of various types, such as CAM and CPM messages. Of course, at least one type of ITS message provides the position of the mobile object. In a first aspect of step S210, at least part of the description information is obtained from one or more CAM messages that provide information about the mobile object as the host object. This means that the CAM messages are sent by an ITS station equipping the mobile object, and the information contained in the CAM messages, such as position and speed, refers to the mobile object itself. For example, the status information about the mobile object, including its position, is obtained from the one or more CAM messages. In another example, both the status information and the reporting information are obtained from the same CAM messages. Of course, a CAM message may be either a basic CAM message according to ETSI standards or an enhanced CAM message as defined by the invention. For example, the reporting information may indicate whether a silent period during which no CAM messages are sent by the ITS station equipping the mobile object has started or has expired. This reporting information may be obtained by analysing whether the originating ITS station stopped or started sending CAM messages. In another example, the reporting information may indicate the start or end of a silent period during which no CAM messages are sent by the ITS station equipping the mobile object. This reporting information may be obtained using enhanced CAM messages, as defined by the invention, which may include additional data elements indicating whether the CAM message is the first sent after a silent period or the last sent before a silent period. For example, the reporting information may be obtained using enhanced CAM messages, as defined by the invention, which may also include additional data elements indicating whether the mobile object is powered up or is powered down. In a second aspect of step S210, at least part of the description information is obtained from one or more CPM messages that provide information about the mobile object as a perceived object. Typically, this means that the CPM messages are sent by an ITS station equipping another mobile object ora roadside unit, and some information contained in the CPM messages, such as position and speed, refers to the mobile object as a detected or observed object. For example, the status information about the mobile object, including its position, is obtained from the one or more CPM messages. In another example, both the status information and the reporting information are obtained from the same CPM messages. Of course, a CPM message may be either a basic CPM message according to ETSI standards or an enhanced CPM message as defined by the invention. For example, the reporting information may indicate a change in the mobility status of the mobile object, either from a static (stationary) object to a moving (in motion) object, or from a moving object to a static object. This reporting information may be obtained by analysing the reporting frequency of the mobile object within successive CPM messages, assuming that a moving object is reported at a higher frequency than a static object. In another example, this reporting information may be obtained by analysing the speed or the speed history of the mobile object as indicated by the status information. In yet another example, the reporting information may indicate whether the mobile object is currently parked or has just left its parking spot. This reporting information may be obtained using enhanced CPM messages, as defined by the invention, which may include additional data elements indicating the mobile object's parking status. In some embodiments, the reporting information about the mobility status of the mobile object may be obtained by analysing the speed or the speed history of the mobile object as indicated by the status information obtained from one or more CAM messages. In other embodiments, the reporting information about the mobility status of the mobile object may be obtained by analysing the speed or the speed history of the mobile object as indicated by the status information obtained from one or more CAM messages and from one or more CPM messages. In a third aspect of step S210, at least part of the description information is obtained from one or more MCM messages that provide information about the mobile object as being part of a manoeuvre coordination. Typically, this means that the MCM messages are sent by an ITS station equipping the mobile object itself, providing several key pieces of information, such as the current position, intended trajectory, and additional dynamic data. For example, the status information about the mobile object, including its position, is obtained from the one or more MCM messages. In another example, both the status information and the reporting information are obtained from the same MCM messages. Of course, an MCM message may be either a basic MCM message according to ETSI standards or an enhanced MCM message as defined by the invention. For example, the reporting information may indicate that the manoeuvre coordination is starting at a parking spot or ending at a parking spot. This information may be obtained by checking whether the starting point or endpoint of the intended trajectory corresponds to a parking spot, or by using enhanced MCM messages that explicitly indicate whether the starting point or endpoint of the intended trajectory corresponds to a parking spot. In a fourth aspect of step S210, the description information is obtained from various types of ITS messages, including CAM, CPM, and MCM messages. For example, the status information may be obtained from CAM or MCM messages, while the reporting information is obtained from CPM messages. One advantage of this fourth aspect of step S210 is its compatibility with both connected (equipped with an ITS station) and non-connected (not equipped with an ITS station) mobile objects. Indeed, status or reporting information obtained from ITS messages sent by the mobile object itself is expected to be more complete and more accurate than status or reporting information obtained from ITS messages sent by another ITS station observing the mobile object. In some embodiments compatible with this fourth aspect of step S210, the description information may be obtained from PODAM, POM or PAIM messages. At step S220, an occupancy status of the parking spot by the mobile object is determined based on the obtained description information about the mobile object. The occupancy status is one of several possible statuses, including at least occupied and available and may also include other statuses such as 'about to be occupied' and 'about to be available'. According to the invention, the occupied status is assigned to the parking spot if the parking spot is occupied by the mobile object, whereas the available status is assigned to the parking spot if the mobile object has left the parking spot or if no mobile object is occupying the parking spot. The position and size of the parking spot may be determined in several ways. One approach may involve identifying the parking spot as occupied by a mobile object, and in this case, the position and size of the parking spot may be inferred from the position and size of the parked mobile object. Another approach involves using ETSI messages dedicated to parking operations, such as those defined in the Parking Availability Service (PAS), which enables an ITS station equipped on a roadside unit or central station to broadcast information about the status of parking areas and individual parking spots, as determined using sensor-based techniques. Another approach utilizes map information from navigation systems, indicating the positions and sizes of individual parking spots. A further approach uses advanced navigation systems equipped with predictive analytics that can estimate the likelihood of finding a parking spot in a specific area based on historical data, real-time traffic conditions, and parking patterns. In a first aspect of step S220, based on the position, and possibly the size, of the parking spot, the occupancy status of the parking spot is determined to be occupied, according to the embodiments of the invention, if the position of the mobile object is within or substantially close, e.g., within a few meters, to the parking spot, and the reporting information indicates that the mobile object is stationary (not in motion). This reporting information may be provided by CAM messages, indicating that a silent period during which no CAM messages are sent has started or is about to start, or indicating that the mobile object is powered-down, or may be provided by CPM messages, indicating a change in the mobility status of the mobile object from a moving object to a static object. In some embodiments, if the reporting information is provided by MCM messages and indicates that the manoeuvre coordination is ending at the parking spot, the occupancy status of the parking sport is determined to be occupied once the required time to complete the manoeuvre has elapsed or once the manoeuvre is close to reaching completion, for instance when the remaining time for reaching completion is below a threshold. In a second aspect of step S220, based on the position, and possibly the size, of the parking spot, the occupancy status of the parking spot is determined to be available, according to embodiments of the invention, if the position of the mobile object is substantially close, e.g., within a few meters, to the parking spot, and the reporting information indicates that the mobile object is in motion (not stationary). This reporting information may be provided by CAM messages, indicating that a silent period during which no CAM messages are sent has expired or has just ended, or may be provided by CPM messages, indicating a change in the mobility status of the mobile object from a static object to a moving object. In some embodiments, if the reporting information is provided by MCM messages and indicates that the manoeuvre coordination is starting at the parking spot, the occupancy status of the parking spot is determined to be available once the required time to start the manoeuvre has elapsed. In a third aspect of step S220, based on the position of the parking spot, the occupancy status of the parking spot is determined to be 'about to be available' or 'about to be occupied', according to embodiments of the invention, if the reporting information is provided by MCM messages and indicates that the manoeuvre coordination is starting or ending at the parking spot, respectively. Optionally, if initially determined to be 'about to be available', the occupancy status of the parking spot may be updated to available once the required time to start the manoeuvre has elapsed or once it is determined that the manoeuvre has started, for instance using updated reporting information. Conversely, if initially determined to be 'about to be occupied', the occupancy status of the parking spot may be updated to occupied once the required time to complete the manoeuvre has elapsed or once the manoeuvre is close to reaching completion, for instance when the remaining time for reaching completion is below a threshold. Additionally, if initially determined to be 'about to be occupied', the occupancy status of the parking spot may be updated to occupied once it is determined that the manoeuvre is finished or is about to finish, for instance using updated reporting information. In some embodiments compatible with the first aspect of step S220, which deals with the occupied parking status of the parking spot, the determined occupied parking status may be subject to continuous verification during a first predefined check period, typically lasting several seconds. If the occupied parking status remains valid throughout this period without the mobile object changing its position, even within the parking spot, the occupied parking status may then be utilized by the processing device for parking operations (if the processing device is equipped on a mobile object) or shared with other ITS stations, preferably those within the vicinity of the parking spot. For example, the sharing may be carried out only if the distance between a current position of the mobile object and the parking spot is less than a first distance threshold. In other embodiments compatible with the second aspect of step S220, which deals the available parking status of the parking spot, the determined available parking status may be subject to continuous verification during a second predefined check period, typically lasting several seconds. If the available parking status remains valid throughout this period, it may then be utilized by the processing device for parking operations (if the processing device is equipped on a mobile object) or shared with other ITS stations, preferably those within the vicinity of the parking spot. For example, the sharing may be carried out only if the distance between a current position of the mobile object and the parking spot is greater than a second distance threshold. Figure 3 is flowchart of a method 300 for determining the occupancy status of a parking spot by a mobile object, according to other embodiments of the invention. The method illustrated in Figure 3 may be implemented in any processing device with the necessary resources to obtain description information about the mobile object from one or more ITS messages, including status information and reporting information, and to determine the occupancy status of the parking spot based on this description information. The description of the embodiments related to Figure 3 will reference a processing device that is part of, or embedded within, a receiving ITS station capable of receiving and properly decoding ITS messages sent within its communication range. At step S310, the presence of a mobile object in the vicinity of the receiving ITS station is detected. This detection may be performed either using an ITS message-based approach, where an ITS message signals the presence of the mobile object, or using a sensor-based approach, where the presence of the mobile object is detected by sensors equipped in the receiving ITS station. In the ITS message-based approach, the mobile object may be signalled actively through ITS messages transmitted by an ITS station equipping the mobile object, such as CAM or MCM messages, or passively through CPM messages that signal the mobile object as a perceived object. The detection may also involve detected objects for which no ITS messages have been received for a time period exceeding a predefined time period threshold, typically a few minutes, classifying these objects as newly detected. Following the initial detection, the mobile object may either continue to be detected in the vicinity of the receiving ITS station or disappear at a certain point in time, for example, if no further ITS messages are received from the mobile object. At step S320, a change in the mobility status of the mobile object is identified, either from stationary to moving or from moving to stationary, from one or more received ITS messages. This change in mobility status may have already occurred, be in progress, or be planned by the mobile object. Preferably, the change in mobility status of the mobile object is identified based on reporting information obtained from the one or more received ITS messages, as highlighted in step S210 and its various aspects. For example, an already occurred change in the mobility status of the mobile object may be determined from CPM messages that report stationary and moving objects at different frequencies. In another example, an in-progress change in mobility status may be identified from enhanced CAM messages that indicate the start or end of a silent period during which no CAM messages are sent by the ITS station equipping the mobile object. Additionally, a planned change in mobility status may be inferred from MCM messages indicating the planned trajectory of the mobile object. At step S330, a position of the mobile object is determined from the one or more received ITS messages. Preferably, the position of the mobile object is determined based on status information obtained from the one or more received ITS messages, as highlighted in step S210 and its various aspects. Of course, if multiple positions are provided across the different ITS messages, only the most recent position may be considered or the multiple positions may be merged into a single position. At step S340, it is also determined whether the position of the mobile object is within the parking spot. If the mobile object is not within the parking spot, it may then be determined how far the object is from the parking spot. As explained in step S220, the position and size of the parking spot may be determined in several ways, including ETSI messages dedicated to parking operations and advanced navigation systems. At step S350, the occupancy status of the parking spot by the mobile object is determined based on description information about the mobile object, including the change in its mobility status identified in step S320 and its position determined in step S330. For example, if a planned or in-progress change in the mobility status of the mobile object from moving to stationary is identified, and the distance between the parking spot and the mobile object is below a first distance threshold, then the occupancy status of the parking spot may be determined as 'about to be occupied'. The status of the parking spot may be updated to occupied if the position of the mobile object is within the parking spot. In another example, if an already occurred change in the mobility status of the mobile object from stationary to moving is identified, and the distance between the parking spot previously occupied by the mobile object and the mobile object exceeds a second distance threshold, then the occupancy status of the parking spot may be determined as available. The determined occupancy status may, for example, be used for parking operations by a vehicle equipped with the receiving ITS station. At step S360, an ITS message containing parking information related to the parking spot is sent, e.g., broadcast, by the receiving ITS station. This parking information includes the determined occupancy status of the parking spot, as well as other details such as the position and size of the parking spot. Preferably, the ITS message containing parking information is a PODAM or POM message. The ITS message may be sent upon detecting a triggering condition. Examples of triggering conditions include, but are not limited to, a change in the occupancy status of the parking spot, the elapsed time since the occupancy status was determined exceeding a broadcasting time threshold, orthe distance between the current position ofthe mobile object and the parking spot being greater than a first broadcasting distance threshold or less than a second broadcasting distance threshold, depending on whether the occupancy status is determined as available or occupied. In some embodiments, when determining that the occupancy status ofthe parking spot is available or 'about to be available', the receiving ITS station may also be configured to broadcast an ITS message within its communication range, such as a DENM message, indicating a risky situation due to the mobile object previously occupying the parking spot performing a manoeuvre to leave the parking spot. In other embodiments, when determining that the occupancy status ofthe parking spot is occupied or 'about to be occupied', the receiving ITS station may also be configured to broadcast an ITS message within its communication range, such as a DENM message, indicating a risky situation due to the mobile object having stopped, with passengers potentially opening doors or exiting the mobile object onto the street. In yet other embodiments, when determining that the occupancy status ofthe parking spot is 'about to be occupied', the receiving ITS station may also be configured to report the parking spot as occupied, or to not report it. This advantageously helps prevent other vehicles to try reaching the parking spot before the vehicle that expressed its intent to use it. In further embodiments, at step S320, it is determined whether the mobile object is powered down, for instance using information contained in received enhanced CAM messages. Then at step S350, the occupancy status ofthe parking spot by the mobile object is determined based on description information about the mobile object, including its powered-down status. For example, if the mobile object is powered-down and the distance between the parking spot and the mobile object is below a distance threshold, then the occupancy status ofthe parking spot may be determined as occupied. Figure 4 is a flowchart of a method 400 for using the occupancy status of a parking spot for parking operations when broadcast in an ITS message within the communication range of an originating ITS station, according to embodiments of the invention. The method illustrated in Figure 4 may be implemented in a receiving ITS station equipping a vehicle that needs to be parked. The description of the embodiments related to Figure 4 will reference such a receiving ITS station. At step S410, it is determined that the vehicle is looking for a parking spot within a designated area. For instance, this may occur when the vehicle is approaching the end of a journey programmed into its navigation system. Alternatively, the driver or a passenger may manually request the navigation system to locate an available parking spot. Additional details about the desired parking spot, such as its size, whether it should be covered, whether it provides charging possibilities, and on which side of the road it should be located, may also be specified. At step S420, one or more ITS messages, such as POIM-PA, PODAM or POM messages, containing parking information related to one or more parking spots are received by the receiving ITS station. Preferably, the parking information for each parking spot includes the position of the spot and an occupancy status indicating whether the spot is available. In some embodiments, the parking information for a parking spot may include an occupancy status indicating that the spot is about to be available. Additional details about the parking spot, such as its size, whether it is covered, and on which side of the road it is located, may also be included. Of course, an ITS message may be received either before or after it is determined that the vehicle is searching for a parking spot within a designated area. Preferably, only ITS messages received within a validity period, typically lasting a few minutes, are considered, as the occupancy status of the parking spot is subject to change. At step S430, a parking spot is searched for parking operations by the vehicle from a list of available parking spots provided by the received ITS messages. This search may be made automatically by the navigation system. For instance, the navigation system may be configured to select a parking spot near the destination of the journey and on the same side of the road as the vehicle. Alternatively, the search may involve prompting the driver or a passenger to choose a parking spot from the list of available parking spots. Additionally, the optimal parking spot may be selected using a hybrid approach involving both the navigation system and the driver or a passenger of the vehicle. In this approach, the navigation system may first filter out available parking spots that are outside the designated area and / or do not meet some or all of the desired characteristics. The driver or passenger then makes the final selection from the remaining parking spots. Of course, step S430 may result in no parking spot being selected for parking operations by the vehicle. This may occur due to the absence of any available parking spots or because none of the available spots is suitable for the vehicle. In some embodiments of step S430, the parking spots are sorted according to their occupancy criteria, following the order available, 'about to be available', 'about to be occupied', occupied, unknown. Possibly, the unknown status may be sorted before or after 'about to be occupied', or at other positions in this list. This advantageously helps selecting a parking spot that is more likely to be available. In some embodiments other search criteria, such as the parking spot size may be used or several criteria may be combined. At step S440, it is checked whether a parking spot has been selected for parking operations by the vehicle. If no parking spot was selected in step S430, a new iteration of loop L401, represented by steps S420 to S440, may be triggered. Preferably, this new iteration of loop L401 may be triggered based on new ITS messages containing updated parking information. The designated area where a parking spot is being searched may possibly be adjusted, for example, by enlarging it. If a parking spot has been selected in step S430, then step S450 is performed. At step S450, an ITS message including parking intention information is sent, e.g., broadcast, by the receiving ITS station within its communication range to indicate that the vehicle intends to occupy the selected parking spot. Preferably, the sent ITS message is a PODAM or a PAIM message. Possibly, the sent ITS message is a basic MCM message, with the destination point of the planned trajectory set to the position of the selected parking spot. Alternatively, the sent ITS message is an enhanced MCM message, as described in the invention, which indicates a destination corresponding to a parking spot, along with information indicating the parking intention and with information identifying the selected parking spot. More generally, the ITS message may be any message that conveys parking intention information, indicating that the parking spot is about to be occupied. Additionally, the vehicle starts navigating towards the selected parking spot. In some embodiments of step S450, if the status of the selected parking spot is 'about to be available', then the vehicle may adapt is navigation towards the selected parking spot depending on the estimated time of availability of the parking spot. For instance, the vehicle may drive more slowly towards the parking spot. As another example, the vehicle may stop near the parking stop at a location enabling the leaving vehicle to easily leave the parking spot, while limiting the impact on other road users and allowing the vehicle to easily manoeuvre into the parking spot once it is available. In some embodiments, loop L401, represented by steps S420 to S440, may continue to iterate even if a parking spot is selected in step S430 of the current iteration. This is done to potentially find a better parking spot, for example, one that is more optimal in terms of distance and convenience for the vehicle. The iteration of loop L401 may stop once a predefined number of iterations threshold is reached. In other embodiments, if no parking spot is selected in step S430 of the current iteration of loop L401, an ITS message, such as a PODAM or POM message, requesting information about available parking spots is broadcast by the receiving ITS station within its communication range. Figure 5 is a flowchart of a method 500 for sharing the occupancy status of a parking spot, by an originating ITS station equipping a vehicle (mobile object) that is about to leave the parking spot, according to embodiments of the invention. The method illustrated in Figure 5 may be implemented in the originating ITS station, and the description of the embodiments related to Figure 5 will reference such an originating ITS station. At step S510, it is determined that the vehicle equipped with the originating ITS station is about to start. This may be identified by detecting that the vehicle's engine has been started or that the driver has entered the vehicle or that the driver has powered on the vehicle. It may also be identified when ITS messages, such as CAM or MCM messages, begin to be sent by the originating ITS station. Of course, a hybrid approach combining both methods may also be adopted for greater accuracy in detecting that the vehicle is about to start. At step S520, it is determined that the vehicle is occupying a parking spot before starting to move. This may be achieved by using the vehicle's current position in conjunction with available map data to confirm that it is within a parking spot. The map data may be provided by the vehicle's internal navigation system. Additionally, the originating ITS station may utilize parking information, which may be either internally stored or received through ITS messages, such as a POIM-PA, a PODAM or a POM message. This combined use of location and parking data ensures accurate identification of the vehicle's presence in a parking spot. At step S530, an ITS message is sent, e.g., broadcast, by the originating ITS station within its communication range, disseminating the vehicle's intention to leave its currently occupied parking spot. Preferably, this ITS message is a basic MCM message indicating that the initial position of a planned trajectory corresponds to the position of the parking spot, or an enhanced MCM message, as described in the invention, indicating that the starting point is a parking spot and including information that indicate the intention to leave the parking spot and information that identifies the parking spot. The enhanced MCM message may also include additional trajectory information based on traffic rules for leaving the parking spot. More generally, the ITS message may be any message that conveys parking intention information, indicating that the parking spot is 'about to be available'. Figure 6 is a flowchart illustrating a method 600 for a receiving ITS station to respond to a parking spot information request sent by an originating ITS station within its communication range, according to embodiments of the invention. The description of the embodiments related to Figure 6 will reference such a receiving ITS station, which may either be fixed, as in the case of a roadside unit, or mobile, as in the case of an equipped vehicle, for example. At step S610, the receiving ITS station receives the parking spot information request, either via unicast, multicast, or broadcast. The request may specify a single parking spot, multiple parking spots, or all parking spots within a designated area. The requested information includes the occupancy status, such as whether the parking spot is occupied or available, and may also include additional details such as the size of the parking spot, whether the parking spot is covered, whether it provides charging capabilities, and the location of the parking spot. For example, a parking spot may be specified using its coordinates in a global coordinate system, such as GPS coordinates. At step S620, the receiving ITS station determines, for each requested parking spot, whether the parking spot is within the field of view of its sensors, as a first approach, and / or whether ITS messages, such as POIM-PA, PODAM or POM messages, containing parking information related to the parking spot are received by the receiving ITS station, as a second approach. Several situations may arise for a requested parking spot: both approaches provide parking information about the parking spot, only one approach provides such parking information, or neither approach is able to provide parking information about the parking spot. For example, the parking information may indicate whether an object is located within the parking spot. Advantageously, the receiving ITS station may first determine the list of parking spots for which information is requested. For example, if the parking spot information request targets parking spots within a designated area, the receiving ITS station may determine the list of parking spots located within this area, using for example map data provided by the receiving ITS station internal navigation system. The receiving ITS station, may also use parking information that may be either internally stored or received through ITS messages, such as a POIM-PA, a PODAM or a POM message. At step S630, the receiving ITS station determines the occupancy status for each requested parking spot for which at least one of the two approaches provides associated parking information. The determined occupancy status may be either available or occupied. If the two approaches provide conflicting information about a parking spot, such as one indicating it is occupied while the other indicates it is available, the sensor-based approach may be prioritized, and the ITS message-based approach may be disregarded. If neither approach can provide parking information about the specified parking spot, its occupancy status may be determined as unknown. Of course, the occupancy status may also be 'about to be available' or 'about to be occupied'. At step S640, the receiving ITS station sends a parking spot information response, either via unicast, multicast, or broadcast. The response indicates the occupancy status for requested parking spots. The parking spot information response may be any ITS message, such as a PODAM or a POM message. For example, the response may indicate the occupancy status only for each requested parking spot for which at least one of the two approaches provides associated parking information. In addition, the response may only indicate the occupancy status for requested parking spot for which the occupancy status is available or 'about to be available', thereby reducing the size of the response message. In some embodiments, an optional loop L601 (not represented in Figure 6), represented by steps S620 and S630, is re-iterated until a completion condition is met. For example, each new iteration of loop L601 may be triggered by a change in the position of the receiving ITS station and / or by the passage of a predefined amount of time and / or by the change of occupancy status for one of the requested parking spots, allowing the receiving ITS station to perceive the requested parking spots from different perspectives. Completion conditions may include reaching a predefined amount of time since the first iteration of loop L601, receiving an ITS message from the originating ITS station indicating that it is no longer interested in the occupancy status of the specified parking spots, or no longer receiving ITS messages requesting the occupancy status of the specified parking spots. In other embodiments, the ITS message-based approach may be used to determine the occupancy status of a specified parking spot only if the associated ITS messages were received within a predefined time period that ends at the time the parking spot information request is received. Preferably, the duration of this predefined time period may depend on factors such as traffic conditions and the variability of parking spot occupancy. Additionally, the parking spot information response may include, in addition to the determined occupancy status of the specified parking spot, the time of reception of the ITS messages used to determine the occupancy status or the time when the occupancy status was determined. Figure 7 illustrates the structure of an enhanced CAM message 700, according to embodiments of the invention. The enhanced CAM message retains the structure of a standard basic CAM message, such as the one specified in ETSI TS 103 900 (V2.1.1, 2023), while incorporating one or more additional data elements. These additional data elements may be integrated either within the same Container or in distinct Containers within the CAM message. The exemplary structure of a standard basic CAM message is highlighted in Figure 7. The ITS PDU Header includes essential data elements such as the Message ID, identifying it as a CAM, and the Protocol Version, ensuring compatibility across ITS stations. The Basic Container contains fundamental information about the ITS station, including the Station Type, Reference Position (latitude, longitude, and altitude), and a Time Stamp indicating when the CAM was generated. The High-Frequency Container holds dynamic data that changes frequently, such as the station's Speed, Heading, Acceleration Control, and Vehicle Dimensions. In contrast, the Low-Frequency Container is optional and stores less frequently changing information like the Vehicle Role (e.g., emergency vehicle or public transport) and Exterior Lights Status. The remaining containers, such as the Special Vehicle Container and the Special Purpose Container, are optional and used for specific scenarios, like detailing the status of emergency vehicles, public transport, or vehicles carrying dangerous goods, providing additional context relevant to specific use cases within the ITS environment. Together, these containers enable the CAM to provide a comprehensive and real-time snapshot of the station's status and environment. Generally, a flag may be represented as a Boolean value. It may also be represented by the presence or absence of a data element. The additional data elements of the enhanced CAM message are preferably integrated within a new Container, referred to as the Start-Stop Container, which is included within the High-Frequency Container. The Start-Stop Container contains a Starting-Information data element and a Stopping-Information data element. Of course, the Start-Stop Container may be included within another Container of the CAM message, such as the Low-Frequency Container. In some embodiments, the Starting-Information indicates that the ITS station sending the CAM message has just started operating. This may be represented as a flag included in the first CAM message generated by the ITS station or during a predefined period after start-up. For example, this flag may be present for up to 2 seconds after the ITS station starts. Alternatively, the Starting-Information may be a duration that indicates the time elapsed since the ITS station started. This duration may also be included only for a predefined period after start-up, such as within the first 2 seconds. The duration may be expressed as an integer representing the number of tenths of a second since the ITS station started. A specific value may be used to indicate that the ITS station has been running for a duration longer than the maximum value indicated by other values. For instance, if a 5-bit value is used, values from 0 to 30 may represent the number of tenths of a second since start-up, while the value 31 may indicate that more than 3.0 seconds have passed since the ITS station started. In other embodiments, the Stopping-Information indicates that the ITS station sending the CAM message is about to stop operating. This may be represented as a flag included in the last CAM message generated by the ITS station or during a predefined period before stopping. For example, this flag may be present for 1 second before the ITS station stops. Alternatively, the Stopping-Information may indicate the time remaining until the ITS station stops. This duration may also be included only for a predefined period before stopping, such as 1 second before the ITS station stops. The duration may be expressed as an integer representing the number of tenths of a second before the ITS station stops. A specific value may be used to indicate that the ITS station will stop after a duration longer than the maximum value represented by other values. For instance, if a 4-bit value is used, values from 0 to 14 may represent the number of tenths of a second before stopping, while the value 15 may indicate that the ITS station will stop in more than 1.4 seconds. In further embodiments, the Start-Stop Container may also include a Powered-Information data element (not represented in Figure 7). The Powered-Information indicates that the ITS station sending the CAM message is powered-down, i.e., that it is not operating. This may be represented as a flag included in the CAM messages generated by the ITS station while it is not operating. Possibly, when the ITS station is not operating, CAM messages are sent with a lower frequency than when the ITS station is operating. For instance, the CAM messages may be sent once every 60 seconds. Possibly, when the ITS station is not operating, some data elements are omitted from the CAM messages sent by the ITS station. Of course, the Starting-Information data element, the Stopping-Information data element, and / or the Powered-Information data element, may be contained in other ITS messages, for example PODAM, POM or PAIM. Figure 8 illustrates the structure of an enhanced MCM message 800, according to embodiments of the invention. The enhanced MCM message retains the structure of a standard basic MCM message, such as the one specified in ETSI TR 103 578 V2.1.1 (2024-04), while incorporating one or more additional data elements. These additional data elements may be integrated either within the same Container or in distinct Containers within the MCM message. The exemplary structure of a standard basic MCM message is highlighted in Figure 8. The ITS PDU Header includes essential data elements such as the Station ID, which identifies the sending station (e.g., the vehicle or roadside unit), the Message ID, which identifies the message as an MCM, and the Protocol Version, ensuring compatibility across ITS stations. The Management Container contains fundamental information about the originating ITS station, including the Station Type, Reference Position (latitude, longitude, and altitude), and a Time Stamp indicating when the MCM was generated. The MCM message may include one or both of the following containers: a Vehicle Manoeuvre Container, which includes a list of possible manoeuvres for the sender vehicle, ora Manoeuvre Advice Container, which provides manoeuvre recommendations for other vehicles. The Vehicle Manoeuvre Container includes the current vehicle automation state, which indicates whether the vehicle is currently driving in automated mode longitudinally, laterally, or both, as well as a trajectory list. The first trajectory in the list is the reference trajectory, which is always included. The Manoeuvre Advice Container contains mainly a list of advised manoeuvres for different vehicles. Each manoeuvre includes a manoeuvre ID, the station ID, position and heading of the vehicle that is expected to execute the manoeuvre, the manoeuvre path, and the automation state in which the manoeuvre should be performed. Generally, a flag may be represented as a Boolean value. It may also be represented by the presence or absence of a data element. In some embodiments, a trajectory from the trajectory list, such as the reference trajectory, may include information indicating that the end of the trajectory is the stopping location of the ITS station. This may be achieved by adding a flag to the trajectory structure indicating whether the trajectory ends at a stopping location of the ITS station. Alternatively, this may also be achieved by adding an optional structure containing information identifying the parking spot where the ITS station intends to stop. This information may be specific to a parking spot. Alternatively, this information may identify a set of parking spots. This information may reuse structures defined by the Parking Availability Service specification. In other embodiments, the Vehicle Manoeuvre Container may include information indicating that the start of the trajectories is the starting location of the ITS station. This may be achieved by adding a flag to the Vehicle Manoeuvre Container indicating whether a trajectory starts at the starting location of the ITS station. Alternatively, this may also be achieved by adding an optional structure containing information identifying the parking spot from which the ITS station is starting. This information may be specific to a parking spot. Alternatively, this information may identify a set of parking spots. This information may reuse structures defined by the Parking Availability Service specification. Of course, the information indicating that the end of the trajectory is the stopping location of the ITS station or the information indicating that the start of the trajectory is the starting location of the ITS station may be included in other types of ITS messages, as for example in a PODAM , a POM or in a PAIM. Figure 9 illustrates the structure of an enhanced PODAM message 900, according to embodiments of the invention. The enhanced PODAM message retains the structure of a standard basic PODAM message, such as the one proposed in contribution ITSWG1 (24)000213 for ETSI TS 104 072, while incorporating one or more additional data elements. These additional data elements may be integrated either within the same Container or in distinct Containers within the PODAM message. An example structure of a standard basic PODAM message is highlighted in Figure 9. The ITS PDU Header includes essential data elements such as the Station ID, which identifies the sending station (e.g., the vehicle or roadside unit), the Message ID, which identifies the message as an PODAM, and the Protocol Version, ensuring compatibility across ITS stations. The BasicContainer contains fundamental information about the originating ITS station, including the Station Type and Reference Position (latitude, longitude, and altitude). The PODAM message may further include one or both of the following containers: a ParkingSpotDetections container, which includes a list of ParkingSpotDetection and a ParkingSpotlntentlndication container. Unlike the above-mentioned ETSI contribution, the present invention proposes that these two containers (ParkingSpotDetections and ParkingSpotlntentlndication) may be, preferably should be, optional because their presence will depend on the usage of the PODAM message. If the PODAM message contains a ParkingSpotlntentlndication container with an associated arrival time (referred to as estimatedArrivalTime), this field being proposed in the ETSI contribution, or a departure time (referred to as estimatedDepartureTime), this field being proposed in this invention, it may also optionally contain a description of the parking spot where the vehicle will arrive at or from which it is departing. The estimatedArrivalTime is sent by a vehicle when it will arrive at a parking spot. The status of the associated parking spot should be reported using the new value 'aboutToBeOccupied' for the ParkingSpaceStatus field. Alternatively, this same status indication may be reported with a value freeUntil with a timestamp equal to the estimatedArrivalTime. The estimatedDepartureTime is sent by a vehicle that is about to leave the parking spot. This may be identified by detecting that the vehicle's engine has been started or that the driver has entered the vehicle or that the driver has powered on the vehicle. In the case of an estimated departure the status of the associated parking spot may be reported using the new value 'aboutToBeFree' for the ParkingSpaceStatus field. This new value may also be named 'aboutToBeAvailable'. Alternatively, this same status indication can be reported with a value occupiedUntil with a timestamp equal to the estimatedDepartureTime. In some embodiments, the IndividualParkingSpot element contains a status field of type ParkingSpaceStatus to allow reporting an about to be occupied or an about to be available status using a ParkingSpaceStatus field for an individual parking spot. In these embodiments, the status field of the IndividualParkingSpot may be optional. If the status field is absent, the individual parking spot is considered as free. If the intent Indication contains a requestForDetection field, as proposed by the invention, with a Boolean value True, the message may have no parking spot detection. In this case the ParkingSpotDetections field is a list of ParkingSpotDetection of size 0. This message can be used by a vehicle searching for a parking spot. It sends this request to obtain information on potentially free parking spots detected by other vehicles or road side units in the neighbourhood. In some embodiments, when the requestForDetection field is set to True, then the ParkingSpotlntentlndication field may contain some information on the area where a parking spot is searched for. A PODAM message may also simply list parking spot detections with no associated intent indication to simply indicates detected available parking spots. In order to avoid broadcasting too many messages and thus to save bandwidth, rules may be defined for the PODAM message emission rate. The PODAM messages with intent indication of arrival may be sent by a vehicle arriving at a short distance of the expected parking spot, e.g., a few hundred meters or one minute before arrival. It can then be repeated with a low frequency, e.g., every second. A PODAM message with an intent of departure may be sent with a low frequency, e.g., every second during a limited period of time, e.g., 1 minute. After this period, it can be estimated that it was a false prediction of departure and the vehicle should stop sending PODAM messages with an intent of departure. Before sending a PODAM message with a request for detection, a vehicle looking for a free parking spot should listen to other PODAM messages. If a PODAM message with a request for detection is received during a predefined period of time, the vehicle should not send a PODAM message with a request for detection. Alternatively, if a PODAM message with a request for detection targeting the area where the vehicle is looking for a free parking spot is received during a predefined period of time, the vehicle should not send a PODAM message with a request for detection. Additionally, if a PODAM message containing a list of ParkingSpotDetection is received during a second predefined period of time, the vehicle should not send a PODAM message with a request for detection. Alternatively, if a PODAM message containing a list of ParkingSpotDetection targeting the area where the vehicle is looking for a free parking spot is received during a second predefined period of time, the vehicle should not send a PODAM message with a request for detection. Otherwise, the vehicle is authorized to send a PODAM message containing a request for detection if it is looking for a free parking spot. The listening phase may for example be selected by the vehicle as a random value between 1 minute and 2 minutes. The random value is useful to avoid that many vehicles try to send the same request simultaneously. A PODAM message with no intent and thus containing only detected free parking spots may be sent by an ITS station that has received a PODAM message with an intent describing a request for detection during a recent interval of time, e.g., during the last 2 minutes and only if it has detected recently a free parking spot, e.g., during the last 5 minutes. The ITS Station may repeat the same message or may update the message with a low frequency, e.g., every second during a limited period of time, e.g., 2 minutes. Possibly the frequency may decrease over the period of time. Possibly the frequency may be increased when the PODAM message contains an update, for instance when there is a newly available or a newly occupied parking spot. An ITS station that is able to monitor several parking spots using either its sensors, received ITS messages or both may send PODAM messages with no intent at a low frequency, e.g., every 5 seconds. In some embodiments, it may send PODAM messages only when detecting a vehicle in the area. In some embodiments, it may send PODAM messages with an empty list of parking spots to indicate that there is no free parking spot in the area. Preferably, it also indicates in the PODAM messages the area where there is no free parking spot. In some embodiments, an ITS station that is powered off, for instance a parked vehicle, may send a PODAM message with no intent after receiving a PODAM with an intent describing a request for detection. To determine if there is any available parking spot in its perception range, the ITS station may use its sensors, it may rely on previously received ITS messages or both. For instance, the ITS station may use its ultrasonic sensors to check if the parking spot in front of it or the parking spot behind it is free or not. The ITS station may repeat the PODAM message or update it at a low frequency, for example every 5 seconds. With these rules, PODAS will avoid sending too many messages when there are no free parking spots because there are limited requests and only free parking spots are reported. When there are many free parking spots, no requests will be sent and thus no reports will be sent. The sending vehicle may be a moving vehicle sending information on parking spot relative to its path. It may be also a stopped vehicle, parked in a parking spot, or not moving because of stopped traffic, and detecting a free parking spot near its static position. When the sending vehicle is a stopped vehicle or a road side unit, the path used to describe a set of parking spots inside a SubsequentParkingSpotSegments may represent a road segment instead of the path of the sender of the PODAM message. An example of PODAM syntax is shown below, according to embodiments of the invention. PodasParameters ::= SEQUENCE { basicContainer BasicContainer, detections ParkingSpotDetections, intentindication ParkingSpotlntentlndication OPTIONAL } ParkingSpotDetections ::= SEQUENCE (SIZE(0..32, ...)) OF ParkingSpotDetection ParkingSpotlntentlndication spotld reporter estimatedArrivalTime estimatedDepartureTime requestForDetection ::= SEQUENCE { Identified OPTIONAL Stationld OPTIONAL, Timestamplts OPTIONAL Timestamplts OPTIONAL Boolean OPTIONAL ParkingSpotDetection ::= SEQUENCE { spotld Identifier2B, source Stationld OPTIONAL, orientation Wgs84Angle OPTIONAL, levelinformation Levelinformation OPTIONAL, location ParkingSpotDetectionLocation, detectionTime Timestamplts, detectionMethod ParkingSpotDetectionMethod, ParkingSpotDetectionLocation ::= CHOICE { individualspot IndividualParkingSpot, subsequentSpots SubsequentParkingSpotSegments, IndividualParkingSpot ::= SEQUENCE { position DeltaPosition, status ParkingSpaceStatus, entrySpace StandardLengthlB OPTIONAL, spotwidth StandardLengthlB OPTIONAL, spotLength StandardLengthlB OPTIONAL, externalLinks ExternalLinks OPTIONAL, } SubsequentParkingSpotSegment ::= SEQUENCE { path Path, spotsOnTheLeft ParkingSpotSegmentDetections OPTIONAL, spotsOnTheRight ParkingSpotSegmentDetections OPTIONAL, spotwidth StandardLengthlB OPTIONAL, spotLength StandardLengthlB OPTIONAL, externalLinks ExternalLinks OPTIONAL, } ((WITH COMPONENTS {..., spotsOnTheLeft PRESENT}) | (WITH COMPONENTS spotsOnTheRight PRESENT})) ParkingSpaceStatus::= unknown free freeUntil aboutToBeFree fullyOccupied partiallyOccupied occupiedUntil aboutToBeOccupied reservedUntil accessBlocked CHOICE { NULL, NULL, Timestamplts, NULL, NULL, INTEGER(0..100) Timestamplts, NULL, Timestamplts, NULL, retrictedUsage NULL Accordingly, the ParkingSpotlntentlndication container contains the estimatedArrivalTime field describing the expected arrival time of a vehicle to a parking spot. It is proposed, according to embodiments of the invention, to add another field estimatedDepartureTime to indicate the expected departure time of a vehicle from a parking spot. The estimatedDepatureTime is sent by a vehicle when it is about to leave its parking spot. This intention may be identified by detecting that the vehicle's engine has been started or that the driver has entered the vehicle or that the driver has powered on the vehicle. This indication will be useful for other vehicles in the neighbourhood searching for free parking spots. Such a vehicle may move to be closer to the parking spot about to be free and already reserve the future place with an PODAM message indicating its intention to park to this place with an intent containing an EstimatedArrivalTime and using the same parking spot identifier as targeted parking spot. The following syntax may be added in an PODAM, according to embodiments of the invention. PodasParameters ::= SEQUENCE { BasicContainer, ParkingSpotDetectionS; ParkingSpotlntentlndication basicContainer detections intentindication ParkingSpotlntentlndication spotld reporter estimatedArrivalT ime ::= SEQUENCE { Identifier2Bj Stationld, Timestamplts OPTIONAL; estimatedDepartureTime Timestamplts OPTIONAL Also, in both cases (a vehicle arriving at a parking spot or departing from a parking spot) the PODAM message may contain the location of the parking spot in the ParkingSpotDetections container with a location of the form of an individual parking spot. The associated detectionMethod may have a value equal to “leavingVehicle” for both the departing vehicle and the arriving vehicle. It is proposed, according to embodiments of the invention, to add a field status of type ParkingSpaceStatus in the Data Element ParkingSpotDetection. In the case of an estimated departure the status of the associated parking spot should indicate that the spot is about to be available. The status can thus be reported with a value occupiedUntil with a timestamp equal to the estimatedDepartureTime. For an arriving vehicle, the status of the associated parking spot should be reported as about to be occupied. The status indication can be reported with a value freeUntil with a timestamp equal to the estimatedArrivalTime. The following syntax may be added in an PODAM, according to embodiments of the invention. ParkingSpotDetection ::= SEQUENCE { spotld Identifier2B, source Stationld OPTIONAL, position DeltaPosition, location ParkingSpotDetectionLocation, detectionTime Timestamplts, detectionMethod ParkingSpotDetectionMethod, status ParkingSpaceStatus } ParkingSpotDetectionMethod ::= BIT STRING { sensor (0), leavingEgo (1), leavingVehicle (2), staticMapInformation (3) } (SIZE(4,...)) ParkingSpaceStatus::= CHOICE { unknown free freeUntil fullyOccupied partiallyOccupied occupiedUntil reservedUntil accessBlocked retrictedUsage NULL, NULL, Timestamplts, NULL, INTEGER(0..100) Timestamplts, Timestamplts, NULL, NULL, } The different addition proposed for the PODAM message may be also be included in other ITS messages as for example in a CAM message or in a CPM message. The proposed usage of the PODAM message and the proposed rules for sending a PODAM message may also be adapted to and used for other messages containing similar information. Figure 10 shows the hardware structure of an ITS station 1000, in which the invention may be implemented. The hardware components are integrated to ensure that the ITS station can handle communication, data processing, security, and management tasks effectively. At the core of the ITS station is the Central Processing Unit (CPU) 1001, which includes a high-performance processor responsible for handling data processing, running ITS applications, and managing communication tasks. Accompanying the CPU is memory, comprising both RAM for temporary data storage and processing, and non-volatile memory (such as flash storage) for storing firmware, software, and data logs. The Communication Interfaces 1002 are crucial for enabling the ITS station to interact with other vehicles and infrastructure. These interfaces include wireless communication modules like the DSRC (Dedicated Short-Range Communications) module, which typically utilizes the IEEE 802.11p standard (ITS-G5 in Europe) for V2V (Vehicle-to-Vehicle) and V2I (Vehicle-to-Infrastructure) communications. Additionally, a cellular communication module supports LTE, 5G, or other cellular standards for long-range communication, facilitating V2N (Vehicle-to-Network) and V2P (Vehicle-to-Pedestrian) interactions. The antenna system includes multiple antennas designed for different frequency bands, supporting DSRC, GPS, and cellular communications, with MIMO (Multiple Input Multiple Output) technology to enhance signal quality and range. For accurate positioning, the ITS station includes a Positioning System 1003, typically featuring a GNSS (Global Navigation Satellite System) receiver that supports systems like GPS, GLONASS, or Galileo, providing precise location, velocity, and timing information. This is complemented by an Inertial Measurement Unit (IMU), which includes accelerometers and gyroscopes that offer additional data for dead reckoning, enhancing positioning accuracy in areas with poor satellite coverage. The station is also equipped with Sensor Interfaces 1004 that allow integration with various vehicle sensors. These interfaces connect to onboard cameras for visual data input, radar or LIDAR systems for distance and object detection, and environmental sensors that provide data on weather, temperature, and other conditions relevant to ITS applications. Security is a critical aspect of the ITS station, managed by Security Modules 1005 such as the Hardware Security Module (HSM) and Trusted Platform Module (TPM). The HSM is a dedicated chip that performs encryption, decryption, and digital signature operations, ensuring secure communication and handling the secure storage of cryptographic keys. The TPM provides additional secure storage for keys and ensures the system's integrity through secure boot processes. The Power Supply Unit (PSU) 1006 is designed to interface with the vehicle's power system, typically operating at 12V or 24V DC. It includes protection circuits for voltage regulation, noise filtering, and a battery backup to maintain operation during short power interruptions or to allow safe shutdown of the system. Networking within the vehicle and with external entities is facilitated by Networking Hardware 1007 such as Ethernet interfaces for wired connections and a CAN (Controller Area Network) bus interface for real-time data exchange with the vehicle's subsystems. The station may also include Wi-Fi and Bluetooth modules for short-range wireless communication within the vehicle or with nearby devices. For data storage, the ITS station uses Non-volatile Storage 1008, such as SSDs or flash storage, for long-term storage of logs, maps, and application data, and Volatile Storage (RAM) for processing tasks and temporary data handling. Finally, to manage heat generated by the CPU and other components, the ITS station employs a Cooling System 1009. This system may include passive cooling solutions like heat sinks, as well as active cooling methods such as fans or liquid cooling systems, depending on the performance requirements and the operating environment of the station. While the present invention has been described with reference to embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. It will be appreciated by those skilled in the art that various changes and modification might be made without departing from the scope of the invention, as defined in the appended claims. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and / or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. The mere fact that different features are recited in mutually different dependent claims does not indicate that a combination of these features cannot be advantageously used. In the preceding embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over, as one or more instructions or code, a computer-readable medium and executed by a hardware-based processing unit. Computer-readable media may include computer-readable storage media, which corresponds to a tangible medium such as data storage media, or communication media including any medium that facilitates transfer of a computer program from one place to another, e.g., according to a communication protocol. In this manner, computer-readable media generally may correspond to (1) tangible computer-readable storage media which is non-transitory or (2) a communication medium such as a signal or carrier wave. Data storage media may be any available media that can be accessed by one or more computers or one or more processors to retrieve instructions, code and / or data structures for implementation of the techniques described in this disclosure. A computer program product may include a computer-readable medium. By way of example, and not limitation, such computer-readable storage media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage, or other magnetic storage devices, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if instructions are transmitted from a website, server, or other remote source using a coaxial cable, fibre optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fibre optic cable, twisted pair, DSL, or 5 wireless technologies such as infrared, radio, and microwave are included in the definition of medium. It should be understood, however, that computer-readable storage media and data storage media do not include connections, carrier waves, signals, or other transient media, but are instead directed to non-transient, tangible storage media. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and 10 Blu-ray disc, where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

Claims

1. A method of communication in an Intelligent Transport System, ITS, including a plurality of ITS stations, ITS-Ss, the method at a receiving ITS-S of the plurality of ITS-Ss comprising:o determining an occupancy status of a parking spot by a mobile object, based on description information related to the mobile object obtained from at least one ITS message, wherein the description information comprises status information, including a position of the mobile object, and reporting information about the mobile object.

2. The method of claim 1, wherein at least part of the description information is obtained from at least one CAM message disseminating information about the mobile object as a host object.

3. The method of claim 1, wherein at least part of the description information is obtained from CPM messages disseminating information about the mobile object as a perceived object.

4. The method of claim 1, wherein at least part of the description information is obtained from a MCM message disseminating information about the mobile object as being part of a manoeuvre coordination.

5. The method of claim 2, wherein the reporting information indicates the start or end of a silent period during which no CAM messages are sent by an originating ITS-S equipping the mobile object.

6. The method of claim 2, wherein the reporting information indicates that a silent period during which no CAM messages are sent by an originating ITS-S equipping the mobile object has started or has expired.

7. The method of claim 5 or 6, wherein determining, as occupied, the occupancy status of the parking spot by the mobile object comprises determining that the position of the mobile object is within or substantially close to the parking spot, and determining that the reporting information indicates the start of the silent period or is indicative that the silent period has started.

8. The method of claim 5 or 6, wherein determining, as available, the occupancy status of the parking spot by the mobile object comprises determining that the position of the mobile object is within or substantially close to the parking spot, and determining that the reporting information indicates the end of the silent period or is indicative that the silent period has expired.

9. The method of claim 3, wherein the reporting information indicates a change in a mobility status of the mobile object, either from a static object to a moving object or from a moving object to a static object.

10. The method of claim 9, wherein determining, as occupied, the occupancy status of the parking spot by the mobile object comprises determining that the position of the mobile object is within or substantially close to the parking spot, and determining that the reporting information indicates a change in the mobility status of the mobile object from a moving object to a static object.

11. The method of claim 9, wherein determining, as available, the occupancy status of the parking spot by the mobile object comprises determining that the position of the mobile object is within or substantially close to the parking spot, and determining that the reporting information indicates a change in the mobility status of the mobile object from a static object to a moving object.

12. The method of claim 4, wherein the reporting information indicates that the manoeuvre coordination for the mobile object starts at a parking spot, or indicates that the manoeuvre coordination for the mobile object ends at a parking spot.

13. The method of claim 12, wherein determining, as 'about to be occupied', the occupancy status of the parking spot by the mobile object comprises determining that the reporting information indicates that the manoeuvre coordination for the mobile object ends at the parking spot, and wherein determining, as occupied, the occupancy status of the parking spot by the mobile object further comprises determining that the required time to complete the manoeuvre has elapsed.

14. The method of claim 12, wherein determining, as 'about to be available', the occupancy status of the parking spot by the mobile object comprises determining that the reporting information indicates that the manoeuvre coordination for the mobile object starts at the parking spot, and wherein determining, as available, the occupancy status of the parking spot by the mobile object further comprises determining that the required time to complete the manoeuvre has elapsed.

15. The method of any one of the preceding claims, wherein the method further comprises sending an ITS message including parking information related to the parking spot, the parking information including the determined occupancy status.

16. The method of claim 15, wherein sending an ITS message including parking information comprises sending an ITS message including parking information upon detecting a triggering condition, and wherein the triggering condition is at least one of:o The elapsed time since the determining of the occupancy status is higher than a predefined check period, while the determined occupancy status remains unchanged;o The distance between a current position of the mobile object and the parking spot is less than a first distance threshold, respectively greater than a second distance threshold, for a determined occupied status, respectively for a determined available status.

17. The method of any one of the preceding claims, wherein the step of determining an occupancy status of a parking spot by a mobile object is carried out in response to receiving a request for determining the occupancy status of the parking spot.

18. A processing device configured to perform a method according to any one of claims 1 to 5 17.

19. A computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out a method according to any one of claims 1 to 17.

20. A computer-readable medium carrying a computer program according to claim 19.1039

Images