A method, apparatus and system for determining path loss

Abstract

The application discloses a method, device and system for determining path loss, which is suitable for the fields of Internet of Vehicles, intelligent driving, intelligent networked vehicle, V2X and the like, and is used for determining the sidelink path loss between two terminal devices. The method comprises the following steps: a first terminal device sends a first reference signal to a second terminal device; the first terminal device obtains a first filtering power according to the transmission power of the first reference signal; and the path loss between the first terminal device and the second terminal device can be determined by combining the first filtering power with the second filtering power indicated by the second terminal device. Since the first filtering power is determined by the first terminal device according to the actual transmission power of the first reference signal, the path loss between the two terminal devices can be determined more accurately, so that the transmission power of the first terminal device can be controlled based on the path loss, and thus the interference on other terminal devices or network devices can be reduced while the communication quality is ensured, and the communication reliability is improved.

Description

Technical Field

[0001] This application relates to the field of wireless communication technology, and in particular to a method, apparatus and system for determining path loss. Background Technology

[0002] In a new radio (NR) vehicle-to-everything (V2X) system, terminal devices can communicate with network devices (such as base stations) via uplink (UL) or downlink (DL), and can also communicate with other terminal devices via sidelink (SL).

[0003] In uplink communication scenarios, terminal devices typically control their uplink transmit power based on downlink path loss. This is to prevent excessive uplink transmit power from affecting the network device's reception of uplink signals from other terminal devices, and to prevent insufficient uplink transmit power from reducing the quality of uplink signals received from the terminal device. For a terminal device, the reference signal receiving power (RSRP) can be obtained by measuring the reference signal from the network device. Based on the RSRP and the reference signal power configured on the network device, the downlink path loss can be determined.

[0004] In side-path communication scenarios, when a transmitting device sends side-path signals to a receiving device, excessive side-path transmit power can affect the receiving device's reception of downlink signals from network devices or side-path signals from other terminal devices; conversely, insufficient side-path transmit power will degrade the quality of the side-path signals received by the receiving device from the transmitting device. To avoid these problems, the transmitting device can control its side-path transmit power. Similar to the method for controlling uplink transmit power, controlling side-path transmit power requires determining the side-path loss. Currently, there is no feasible method for determining side-path loss. Summary of the Invention

[0005] This application provides a method, apparatus, and system for determining path loss between two terminal devices.

[0006] In a first aspect, embodiments of this application provide a method for determining path loss, comprising: a first terminal device first sending a first reference signal to a second terminal device; the first terminal device obtaining a first filtered power based on the transmission power of the first reference signal; the first terminal device receiving first indication information from the second terminal device, the first indication information being used to indicate a second filtered power, the second filtered power being a power determined based on the first reference signal; and then the first terminal device determining the path loss between the first terminal device and the second terminal device based on the first filtered power and the second filtered power.

[0007] In one possible design, the terminal device can be a vehicle or an in-vehicle module or assembly built into a vehicle, or it can be a smartphone, smartwatch, or the like.

[0008] In this embodiment, the first terminal device determines a first filtered power based on the transmission power of the first reference signal, and then, in conjunction with the second filtered power indicated by the second terminal device, determines the path loss between the first and second terminal devices. Since the first filtered power is determined by the first terminal device based on the actual transmission power of the first reference signal, the path loss between the two terminal devices can be determined relatively accurately based on this first filtered power. Subsequently, the transmission power of the first terminal device can be controlled based on this path loss, thereby ensuring communication quality while reducing interference to other terminal devices or network devices and improving communication reliability.

[0009] In one possible design, the first filter power is obtained based on at least one of a first filter coefficient, the transmission power of a first reference signal, or a third filter power. The third filter power is obtained by the first terminal device based on the transmission power of a second reference signal, or is the transmission power of the first reference signal. The second reference signal is a reference signal transmitted by the first terminal device to the second terminal device before transmitting the first reference signal. In the above design, the first filter power used to determine the path loss can be obtained based on at least one of the first filter coefficient, the transmission power of the first reference signal, or the third filter power, thereby enabling the determination of the path loss between the two terminal devices.

[0010] In one possible design, the first filtering coefficient may be configured by the network device, or may be obtained from the configuration information of the resource pool, or may be configured by the first terminal device, or may be a first initial filtering coefficient, which is a parameter configured at the factory.

[0011] In the above design, the first terminal device can determine the path loss between two terminal devices based on the first filtering coefficient configured by the network device; or, the first terminal device can obtain the first filtering coefficient from the configuration information of the resource pool, and then determine the path loss based on the first filtering coefficient. In this design, the first terminal device can obtain the first filtering coefficient without interacting with the network device, which can save network resources and reduce communication complexity; or, the first filtering coefficient is configured by the first terminal device itself. In this design, the first terminal device can configure the first filtering coefficient itself in scenarios without network device configuration or resource pool configuration, which is highly adaptable and flexible; or, the first filtering coefficient is the first initial filtering coefficient configured at the factory. In this design, the first filtering coefficient can be directly obtained from the factory-configured parameters without self-configuration or interaction with the network device or resource pool, which simplifies the implementation process and is easy to implement.

[0012] In one possible design, when the first filter coefficient is configured by the first terminal device, the method further includes: the first terminal device sending second indication information to the second terminal device, the second indication information indicating a second filter coefficient used to determine the second filter power. In the above design, when the first filter coefficient is configured by the first terminal device, the first terminal device also needs to configure a second filter coefficient for the second terminal device to determine the second filter power and indicate the second filter coefficient to the second terminal device, which allows the second terminal device to determine the second filter power more accurately.

[0013] In one possible design, the first terminal device obtains a first filtered power based on the transmission power of a first reference signal, including: the first terminal device filtering the transmission power of the first reference signal to obtain the first filtered power. In the above design, the first terminal device obtains the first filtered power for determining path loss through filtering, thereby improving the accuracy of path loss.

[0014] In one possible design, the first filter power satisfies the following formula:

[0015] P n = (1-b)×P n-1 +b×L n

[0016] Among them, P n P represents the first filter power. n-1 L represents the third filter power. n The first reference signal is transmitted at power , b is the weighting coefficient, the value of b is related to the first filter coefficient, and n indicates that the first reference signal is transmitted for the nth time, where n is an integer greater than or equal to 1.

[0017] In the above design, the first filter power is determined by the instantaneous value of the transmission power of the first reference signal (i.e., the transmission power of the first reference signal) and the previously obtained filter power. This avoids the problem of excessive error in the calculated path loss caused by a sudden increase or decrease in the instantaneous value of the transmission power, and thus can determine the path loss between the two terminal devices more accurately.

[0018] In one possible design, when n equals 1, the third filter power is the transmit power of the first reference signal. In the above design, when the first reference signal is transmitted for the first time, the third filter power is the transmit power of the first reference signal to determine the path loss between the two terminal devices.

[0019] In one possible design, the path loss between the first terminal device and the second terminal device includes the difference between the first filter power and the second filter power, or the ratio of the first filter power to the second filter power. In the above design, the first terminal device can calculate the path loss between the two terminal devices based on simple difference calculations or simple ratio calculations, which requires little computation and is easy to implement.

[0020] In one possible design, the method further includes: the first terminal device determining the transmit power of the first reference signal based on higher-layer configuration parameters. In the above design, the first terminal device can determine the transmit power of the first reference signal through higher-layer configuration parameters to determine the path loss between the two terminal devices.

[0021] Secondly, embodiments of this application provide a method for determining path loss, comprising: a first terminal device first sending a first reference signal to a second terminal device; the first terminal device receiving first indication information from the second terminal device, the first indication information being used to indicate a second filtering power, the second filtering power being a power determined according to the first reference signal; and then the first terminal device determining the path loss between the first terminal device and the second terminal device according to the transmission power of the first reference signal and the second filtering power.

[0022] In one possible design, the terminal device can be a vehicle or an in-vehicle module or assembly built into a vehicle, or it can be a smartphone, smartwatch, or the like.

[0023] In this embodiment, the first terminal device can determine the path loss between the first terminal device and the second terminal device based on the transmission power of the first reference signal and the second filtering power indicated by the second terminal device. Since the actual transmission power of the first reference signal does not need to be calculated, determining the path loss based on the transmission power of the first reference signal and the second filtering power reduces the amount of processing required, is easy to implement, and allows for subsequent control of the transmission power of the first terminal device based on the determined path loss. This ensures communication quality while reducing interference to other terminal devices or network devices, thereby improving communication reliability.

[0024] In one possible design, the first terminal device sends second indication information to the second terminal device. This second indication information indicates a second filtering coefficient, which is used to determine the second filtering power. In this design, the first terminal device also needs to configure the second terminal device with the second filtering coefficient for determining the second filtering power and indicate this second filtering coefficient to the second terminal device, so that the second terminal device can determine the second filtering power more accurately.

[0025] In one possible design, the method further includes: the first terminal device determining the transmit power of the first reference signal based on higher-layer configuration parameters. In the above design, the first terminal device can determine the transmit power of the first reference signal through higher-layer configuration parameters to determine the path loss between the two terminal devices.

[0026] In one possible design, the path loss between the first terminal device and the second terminal device includes the difference between the transmit power of the first reference signal and the second filtered power, or the ratio of the transmit power of the first reference signal to the second filtered power. In the above design, the first terminal device can calculate the path loss between the two terminal devices based on simple difference calculations or simple ratio calculations, which requires little computation and is easy to implement.

[0027] Thirdly, embodiments of this application provide a method for determining path loss, the method comprising: a second terminal device first receiving a first reference signal from a first terminal device; the second terminal device obtaining a second filtered power based on the received power of the first reference signal, the second filtered power being used to determine the path loss between the first terminal device and the second terminal device; and then the second terminal device sending first indication information to the first terminal device, the first indication information being used to indicate the second filtered power.

[0028] In one possible design, the terminal device can be a vehicle or an in-vehicle module or assembly built into a vehicle, or it can be a smartphone, smartwatch, or the like.

[0029] In this embodiment, the second terminal device determines a second filtering power based on the received power of the first reference signal, and then instructs the first terminal device on the second filtering power, so that the first terminal device can determine the path loss between the first terminal device and the second terminal device. Since the second filtering power is determined by the second terminal device based on the actual received power of the first reference signal, the path loss between the two terminal devices can be determined relatively accurately based on this second filtering power. Therefore, the first terminal device can subsequently control its transmission power based on the determined path loss, thereby ensuring communication quality while reducing interference to other terminal devices or network devices and improving communication reliability.

[0030] In one possible design, the second filter power is obtained based on at least one of a second filter coefficient, the received power of the first reference signal, or a fourth filter power. The fourth filter power is obtained by the second terminal device based on the received power of the second reference signal, or it is the received power of the first reference signal. The second reference signal is a reference signal received by the second terminal device before receiving the first reference signal. In the above design, the second filter power used to determine the path loss can be obtained based on at least one of the second filter coefficient, the received power of the first reference signal, or the fourth filter power, thereby enabling the determination of the path loss between the two terminal devices.

[0031] In one possible design, the second filter coefficient is configured by the network device, obtained from the configuration information of the resource pool, configured by the first terminal device, or is a second initial filter power, which is a parameter configured at the factory.

[0032] In the above design, the second terminal device can determine the path loss between the two terminal devices based on the second filtering coefficient configured by the network device, enabling the first terminal device to determine the path loss based on the second filtering power. Alternatively, the second terminal device can obtain the second filtering coefficient from the configuration information of the resource pool and then determine the path loss based on the second filtering coefficient. In this design, the second terminal device can obtain the second filtering coefficient without interacting with the network device, saving network resources and reducing communication complexity. Alternatively, the second filtering coefficient can be configured by the first terminal device. In this design, the first terminal device can automatically configure the second filtering coefficient for the second terminal device in scenarios without network device configuration or resource pool configuration, exhibiting strong adaptability and high flexibility. Alternatively, the second filtering coefficient can be directly obtained from the factory-configured parameters, without requiring configuration by the first terminal device or interaction with the network device or resource pool, simplifying the implementation process and making it easy to implement.

[0033] In one possible design, when the second filter coefficient is configured by the first terminal device, the method further includes: the second terminal device receiving second indication information from the first terminal device, the second indication information indicating the second filter coefficient. In the above design, when the second filter coefficient is configured by the first terminal device, the second terminal device also receives the second filter coefficient configured by the first terminal device for the second terminal device, which allows the second terminal device to determine the second filter power more accurately.

[0034] In one possible design, the second terminal device obtains the second filtered power based on the received power of the first reference signal, including: the second terminal device filters the received power of the first reference signal to obtain the second filtered power. In the above design, the second terminal device obtains the second filtered power for determining path loss through filtering, thereby improving the accuracy of path loss.

[0035] In one possible design, the second filter power satisfies the following formula:

[0036] F n = (1-a)×F n-1 +a×M n

[0037] Among them, F n F represents the second filter power. n-1 M represents the fourth filter power. n The received power of the first reference signal is represented by , a represents the weighting coefficient, the value of a is related to the second filter coefficient, and n indicates that the first reference signal is transmitted for the nth time, where n is an integer greater than or equal to 1.

[0038] In the above design, the second filter power is determined by the instantaneous value of the received power of the first reference signal (i.e., the received power of the first reference signal) and the previously obtained filter power. This avoids the problem of excessive error in the calculated path loss due to a sudden increase or decrease in the instantaneous value of the received power, and thus can determine the path loss between the two terminal devices more accurately.

[0039] In one possible design, when n equals 1, the fourth filter power is the received power of the first reference signal. In the above design, when the first reference signal is transmitted for the first time, the fourth filter power is the received power of the first reference signal to determine the path loss between the two terminal devices.

[0040] In one possible design, the method further includes: the second terminal device measuring the first reference signal to obtain the received power of the first reference signal. In the above design, the second terminal device can determine the path loss between the two terminal devices by measuring the first reference signal to obtain the received power of the first reference signal.

[0041] Fourthly, embodiments of this application provide an apparatus for determining path loss. This apparatus can be a terminal device, or a chip or chipset within a terminal device, wherein the terminal device can be either a first terminal device or a second terminal device. The apparatus can include a transceiver module and a processing module. When the apparatus is a terminal device, the processing module can be a processor, and the transceiver module can be a transceiver. The apparatus can also include a storage module, which can be a memory. The storage module stores instructions, and the processing module executes the instructions stored in the storage module to cause the first terminal device to perform the corresponding function described in the first aspect; or, the processing module executes the instructions stored in the storage module to cause the first terminal device to perform the corresponding function described in the second aspect; or, the processing module executes the instructions stored in the storage module to cause the second terminal device to perform the corresponding function described in the third aspect. When the device is a chip or chipset within a communication device, the processing module can be a processor, and the transceiver module can be an input / output interface, pins, or circuits, etc. The processing module executes instructions stored in the storage module to cause the first terminal device to perform the corresponding function in the first aspect described above; or, the processing module executes instructions stored in the storage module to cause the first terminal device to perform the corresponding function in the second aspect described above; or, the processing module executes instructions stored in the storage module to cause the second terminal device to perform the corresponding function in the third aspect described above. The storage module can be a storage module within the chip or chipset (e.g., a register, cache, etc.), or it can be a storage module located outside the chip or chipset within the terminal device (e.g., a read-only memory, random access memory, etc.).

[0042] Fifthly, embodiments of this application provide an apparatus for determining path loss, comprising: a processor, and may further include a communication interface and / or a memory. The communication interface is used for transmitting information, and / or messages, and / or data between the apparatus and other devices. The memory is used to store computer-executable instructions, and when the apparatus is running, the processor executes the computer-executable instructions stored in the memory to cause the apparatus to perform a method for determining path loss as described in the first aspect or any design in the first aspect, the second aspect or any design in the second aspect, or the third aspect or any design in the third aspect.

[0043] In a sixth aspect, embodiments of this application also provide a computer-readable storage medium for storing computer instructions that, when executed on a computer, cause the computer to perform the method for determining path loss of the first aspect or any possible design of the first aspect, the second aspect or any possible design of the second aspect, or the third aspect or any possible design of the third aspect.

[0044] In a seventh aspect, this application also provides a computer program product including instructions for storing computer instructions that, when executed on a computer, cause the computer to perform a method for determining path loss for the first aspect or any possible design of the first aspect, the second aspect or any possible design of the second aspect, or the third aspect or any possible design of the third aspect.

[0045] Eighthly, this application also provides a system for determining path loss, the system comprising a first terminal device and a second terminal device, wherein the first terminal device can perform the corresponding functions in the first or second aspect described above, and the second terminal device can perform the corresponding functions in the third aspect described above.

[0046] Ninthly, an embodiment of this application provides a chip, the chip including at least one processor and a communication interface, the processor being coupled to a memory, for reading a computer program stored in the memory to execute a method for determining path loss in the first aspect or any design in the first aspect, the second aspect or any design in the second aspect, or the third aspect or any design in the third aspect of the embodiments of this application.

[0047] In a tenth aspect, embodiments of this application provide a chip including a communication interface and at least one processor, the at least one processor being configured to perform a method for determining path loss according to the first aspect or any possible design of the first aspect, the second aspect or any possible design of the second aspect, or the third aspect or any possible design of the third aspect of embodiments of this application. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of a V2X scenario to which this application embodiment applies;

[0049] Figure 2 This is a schematic diagram of another V2X scenario to which the embodiments of this application are applicable;

[0050] Figure 3 This is a schematic diagram of another V2X scenario to which the embodiments of this application are applicable;

[0051] Figure 4 This is a schematic diagram of an NR V2X scenario to which this application embodiment applies;

[0052] Figure 5 A schematic flowchart illustrating a method for determining downlink path loss applicable to embodiments of this application;

[0053] Figure 6 This application provides a schematic flowchart of a method for determining path loss in an embodiment of the present application.

[0054] Figure 7This is a schematic diagram of the structure of the physical resource block applicable to the embodiments of this application;

[0055] Figure 8 This is a schematic flowchart of another method for determining path loss provided in an embodiment of this application;

[0056] Figure 9 A schematic diagram of a device for determining path loss provided in an embodiment of this application;

[0057] Figure 10 A schematic diagram of another device for determining path loss provided in an embodiment of this application;

[0058] Figure 11 A schematic diagram of another device for determining path loss provided in an embodiment of this application;

[0059] Figure 12 A schematic diagram of another device for determining path loss provided in an embodiment of this application;

[0060] Figure 13 A schematic diagram of another device for determining path loss provided in an embodiment of this application;

[0061] Figure 14 A schematic diagram of another device for determining path loss provided in an embodiment of this application. Detailed Implementation

[0062] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the embodiments of this application will be further described in detail below with reference to the accompanying drawings. Some terms used in the embodiments of this application will be explained below to facilitate understanding by those skilled in the art.

[0063] 1) A terminal device, including means for providing voice and / or data connectivity to a user. The terminal device may include means for providing voice to a user, or means for providing data connectivity to a user, or means for providing both voice and data connectivity to a user. For example, it may include a handheld device with wireless connectivity, or a processing device connected to a wireless modem. The terminal device may communicate with the core network via a radio access network (RAN), exchanging voice or data with the RAN, or interacting with the RAN for both voice and data. The terminal device may include user equipment (UE), wireless terminal equipment, mobile terminal equipment, device-to-device (D2D) terminal equipment, V2X terminal equipment, machine-to-machine / machine-type communications (M2M / MTC) terminal equipment, Internet of Things (IoT) terminal equipment, subscriber unit, subscriber station, mobile station, remote station, access point (AP), remote terminal, access terminal, user terminal, user agent, or user device, etc. For example, it may include mobile phones (or "cellular" phones), computers with mobile terminal devices, portable, pocket-sized, handheld, or computer-embedded mobile devices, etc. Examples include personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, and personal digital assistants (PDAs). It also includes limited devices, such as those with low power consumption, limited storage capacity, or limited computing power. Examples include information sensing devices such as barcode scanners, radio frequency identification (RFID), sensors, global positioning systems (GPS), and laser scanners.

[0064] As an example and not a limitation, in this embodiment, the terminal device can also be a wearable device, etc. Wearable devices, also known as wearable smart devices, are a general term for devices that utilize wearable technology to intelligently design and develop everyday wearables, such as glasses, gloves, watches, clothing, and shoes. Wearable devices are portable devices that are worn directly on the body or integrated into the user's clothing or accessories. Wearable devices are not merely hardware devices, but also achieve powerful functions through software support, data interaction, and cloud interaction. Broadly speaking, wearable smart devices include those that are feature-rich, large in size, and can achieve complete or partial functions without relying on a smartphone, such as smartwatches or smart glasses, as well as those that focus on a specific type of application function and require the use of other devices such as smartphones, such as various smart bracelets, smart helmets, and smart jewelry for vital sign monitoring.

[0065] The various terminal devices described above, if located on a vehicle (e.g., placed inside or installed inside a vehicle), can be considered as vehicle-mounted terminal devices, also known as on-board units (OBUs). If located on roadside terminal devices (e.g., placed inside or installed inside a roadside unit), they can be considered as roadside terminal devices, also known as roadside units (RSUs). The terminal device of this application can also be an on-board module, on-board unit, on-board component, on-board chip, or on-board unit built into a vehicle as one or more components or units. The vehicle can implement the methods of this application through the built-in on-board module, on-board unit, on-board component, on-board chip, or on-board unit.

[0066] In this application embodiment, the device for implementing the functions of the terminal device can be a terminal equipment or a device capable of supporting the terminal device in implementing the functions, such as a chip system, which can be installed in the terminal device. In this application embodiment, the chip system can consist of one or more chips, or it can include chips and other discrete devices. In the technical solutions provided in this application embodiment, the terminal device is used as an example to describe the technical solutions provided in this application embodiment.

[0067] 2) A network device, including, for example, access network (AN) equipment, such as a base station (e.g., an access point), can refer to a device in the access network that communicates with a wireless terminal device over an air interface via one or more cells, or, for example, a network device in a V2X technology, an RSU. The network device can be used to convert received air frames to and from IP packets, acting as a router between the terminal device and the rest of the access network, which may include an IP network. The RSU can be a fixed infrastructure entity supporting V2X applications and can exchange messages with other entities supporting V2X applications. The network device can also coordinate the management of air interface attributes. For example, the network device may include an evolved base station (NodeB or eNB or e-NodeB) in a long term evolution (LTE) system or a long term evolution-advanced (LTE-A) system, or it may include a next generation node B (gNB) in a 5th generation (5G) new radio (NR) system (also referred to as NR system), or it may include a centralized unit (CU) and a distributed unit (DU) in a cloud radio access network (Cloud RAN) system. The embodiments of this application are not limited.

[0068] Network devices may also include core network equipment, such as access and mobility management function (AMF), security anchor function (SEAF), authentication server function (AUSF), core network function (CN function), or unified data management (UDM).

[0069] In this application embodiment, the device used to implement the function of the network device can be a network device itself, or a device capable of supporting the network device in implementing that function, such as a chip system. This device can be installed in the network device. In the following description, the technical solutions provided by the embodiments of this application will primarily be described using the example of a network device as the device for implementing the function of the network device.

[0070] 3) The terms "system" and "network" in the embodiments of this application can be used interchangeably. "Multiple" refers to two or more; therefore, in the embodiments of this application, "multiple" can also be understood as "at least two". "At least one" can be understood as one or more, for example, one, two, or more. For example, including at least one means including one, two, or more, and is not limited to which ones are included. For example, including at least one of A, B, and C, then it can include A, B, C, A and B, A and C, B and C, or A and B and C. Similarly, the understanding of descriptions such as "at least one" is similar. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / ", unless otherwise specified, generally indicates that the preceding and following related objects have an "or" relationship.

[0071] 4) Filtering refers to filtering the transmit power of the reference signal on the transmitting device side based on filter coefficients to obtain the filtered power on the transmitting device side; or it refers to filtering the RSRP on the receiving device side based on filter coefficients to obtain the filtered power on the receiving device side. Further, this filtering can be higher-layer filtering, which refers to filtering at a higher level (such as the radio resource control (RRC) layer). The filter coefficients are parameters used for filtering; the filter coefficients on the transmitting device side and the filter coefficients on the receiving device side can be the same parameter or different parameters. The filtered power on the transmitting device side can be the reference signal power used to determine path loss, and the filtered power on the receiving device side can be the higher-layer filtered RSRP used to determine path loss. Furthermore, unless otherwise specified, both the transmitting device and the receiving device are terminal devices.

[0072] Unless otherwise stated, the ordinal numbers such as "first" and "second" mentioned in the embodiments of this application are used to distinguish multiple objects, and are not used to limit the order, sequence, priority or importance of multiple objects, and the description of "first" and "second" does not limit the objects to necessarily being different.

[0073] The preceding text introduced some terms and concepts involved in the embodiments of this application. The following text describes the relevant technologies of the embodiments of this application.

[0074] Wireless communication technology has undergone rapid development, progressing through the first generation of wireless communication systems based on analog communication systems, the second generation represented by the Global System for Mobile Communication (GSM) system, the third generation represented by the Wideband Code Division Multiple Access (WCDMA) system, and the fourth generation represented by the LTE system, which has achieved great success and is now widely used worldwide. The services supported by wireless communication systems have also evolved from initial voice and SMS to support high-speed wireless data communication. Simultaneously, the number of wireless connections is growing rapidly, and various new wireless service types are emerging, such as the Internet of Things (IoT) and autonomous driving, which place higher demands on future wireless communication systems (such as 5G wireless communication systems).

[0075] The Internet of Things (IoT) is a network that extends and expands upon the internet provided by communication systems. It connects things to each other and things to people through various devices and technologies such as information sensors, RFID, GPS, infrared sensors, and laser scanners. IoT applications are widespread, including in intelligent transportation. With the development of transportation informatization and intelligent transportation, the concept of the Internet of Vehicles (IoV) has emerged. IoV primarily refers to the use of wireless communication technology by onboard devices in vehicles to effectively route dynamic information from all vehicles on an information network platform, providing various functional services during vehicle operation. The aim is to improve vehicle safety, automated driving, and traffic efficiency. The realization of IoV mainly relies on V2X technology, the core of which lies in enabling the interconnection of vehicles with everything around us.

[0076] Please see Figures 1-3 V2X can specifically include vehicle-to-vehicle (V2V) (e.g.) Figure 1 As shown), vehicle-to-pedestrian (V2P) (as shown) Figure 2 As shown), there are four application scenarios: vehicle-to-infrastructure (V2I), vehicle-to-network (V2N), etc. Figure 3(As shown). Here, V2V refers to communication between vehicles; V2P refers to communication between vehicles and people (such as pedestrians, cyclists, drivers, or passengers); V2I refers to communication between vehicles and roadside units; and V2N refers to communication between vehicles and base stations / networks. Through communication with other vehicles, pedestrians, and network infrastructure, vehicles can obtain real-time information about surrounding road conditions, thereby better assisting vehicle driving and even achieving autonomous driving.

[0077] Because V2X communication involves high-speed mobile devices such as vehicles, typical application scenarios include intelligent vehicles, autonomous driving, remote driving, and intelligent transportation systems. For security reasons, these application scenarios have extremely high requirements for communication latency and reliability. Based on LTE networks, the 3rd Generation Partnership Project (3GPP) proposed LTE V2X. LTE V2X can initially support basic V2X communication needs. However, for future applications such as fully intelligent driving and autonomous driving, the current LTE V2X cannot provide sufficient support. With the development of NR technology within the 3GPP standards organization, NR V2X will further evolve. To support more advanced service scenarios (such as platooning, cooperative sensing, and remote driving), NR V2X proposes supporting lower transmission latency (e.g., as low as 20ms), more reliable communication transmission (e.g., up to 99.999%), and higher throughput (e.g., up to 1Gbps) to meet the needs of a wider range of application scenarios.

[0078] In LTE and NR systems, terminal devices can control their uplink transmit power to avoid interference with network devices receiving uplink information from other terminal devices due to excessive uplink transmit power, or to prevent reduced quality of uplink signals received from the same terminal device due to insufficient uplink transmit power. This reduces transmission latency and improves communication reliability. Typically, terminal devices should control their uplink transmit power based on uplink path loss. However, considering the reciprocity of uplink and downlink, uplink path loss and downlink path loss can be considered approximately equal. Furthermore, the reference signal power used to calculate downlink path loss is configured by the network device, reducing computational load. This means that downlink path loss is easier to obtain than uplink path loss. Therefore, terminal devices typically control their uplink transmit power based on downlink path loss.

[0079] In NR V2X systems, terminal devices can communicate with network devices not only via uplink or downlink, but also via sidelinks with other terminal devices. See also... Figure 4 This is a schematic diagram of an NR V2X system. For example... Figure 4 As shown, the NR V2X system 400 includes a network device 1 (such as a base station) and multiple terminal devices ( Figure 4 The system includes terminal device 2 and terminal device 3 (taking a vehicle as an example). Terminal device 2 can communicate with network device 1 via uplink or downlink, and can also communicate with other terminal devices via lateral links. In other words, the NRV2X system includes not only uplink and downlink communication scenarios but also lateral communication scenarios. In the lateral communication scenario, when terminal device 2 sends lateral signals to terminal device 3, if the lateral transmission power is too high, it will affect terminal device 3's reception of downlink signals from network device 1 or lateral signals from other terminal devices; conversely, if the lateral transmission power is too low, it will reduce the quality of the lateral signals received by terminal device 3 from terminal device 2.

[0080] To avoid the above problems, in the NR V2X system, when two terminal devices communicate through a side link, the transmitting device (such as terminal device 2) supports the following four power control methods: 1) power control based on downlink path loss; 2) power control based on side link loss; 3) power control based on both downlink path loss and side link loss; 4) the transmitting device transmits signals at its maximum allowed transmit power.

[0081] A transmission time slot in a communication link can include one or more communication channels. When multiple transmission channels are transmitting within a single time slot, power control needs to be applied to each channel individually to meet transmission requirements. The following section uses the control of the transmission power of the physical sidelink share channel (PSSCH) as an example to introduce NRV2X power control.

[0082] When the transmitting device supports power control based on downlink path loss and sidelink path loss, the transmission power of the PSSCH can satisfy the following formula:

[0083] P PSSCH (i)=min(P CMAX P MAX，CBR ,min(P PSSCH，D (i), P PSSCH，SL (i))) (1)

[0084] Among them, P PSSCH (i) represents the transmission power of PSSCH, P CMAX Indicates the maximum allowable transmission power of the transmitting device; P MAX，CBR Indicates the maximum allowable transmit power on the side link where the transmitting device is located; P PSSCH，D (i) represents the power obtained after power control based on downlink path loss, PPSSCH，SL (i) represents the power obtained after power control based on the side path loss; i represents the i-th transmission, and i is an integer greater than or equal to 1.

[0085] For example, the power obtained after power control based on downlink path loss can satisfy the following formula:

[0086]

[0087] Among them, P PSSCH，D (i) represents the power obtained after power control based on downlink path loss, P 0，D PL represents the desired received power of the receiving device (such as a network device). D α represents the downlink path loss. D This represents the downlink path loss compensation parameter. The value of μ is related to the subcarrier spacing Δf used for PSSCH transmission, for example, Δf = 2. μ 15kHz; This indicates the number of resource blocks allocated for the PSSCH transmission. P 0，D and α D It can be obtained from high-level configuration parameters.

[0088] Similarly, the power obtained after power control based on lateral path loss can satisfy the following formula:

[0089]

[0090] Among them, P PSSCH，SL (i) represents the power obtained after power control based on lateral path loss, P 0，SL P 0，D PL represents the desired receiving power of the receiving device (such as terminal device 3). SL α represents the lateral path loss. SL This represents the side-path loss compensation parameter. The value of μ is related to the subcarrier spacing Δf used for PSSCH transmission, for example, Δf = 2. μ 15kHz; This indicates the number of resource blocks allocated for the PSSCH transmission. P 0，SL and α SL It can be obtained from high-level configuration parameters.

[0091] If the transmitting device is configured with P 0，D and α D However, P is not configured. 0，SL and α SL This indicates that the transmitting device supports power control based on downlink path loss; if the transmitting device is configured with P 0，SL and α SL However, P is not configured.0，D and α D This indicates that the transmitting device supports power control based on sidepath loss; if the transmitting device is configured with P 0，D α D P 0，SL and α SL This indicates that the transmitting device supports power control based on downlink path loss and sidelink path loss; if the transmitting device is not configured with P... 0，D α D P 0，SL or α SL This indicates that the transmitting device is transmitting a signal at its maximum permissible transmission power.

[0092] From equations (1) to (3), it can be seen that when controlling the transmit power of the transmitting device in an NR V2X system, it is necessary to determine the downlink path loss (i.e., PL). D ), and / or lateral path loss (i.e., PL) SL The following section will first introduce how downlink path loss is determined. Please refer to [link / reference]. Figure 5 The flowchart shows the method for determining downlink path loss.

[0093] S1. The network device first sends a reference signal to the terminal device, and the terminal device receives the reference signal from the network device.

[0094] The reference signal is typically sent to the terminal device along with control signaling or data.

[0095] S2. The terminal device measures the reference signal to obtain RSRP.

[0096] S3. The network device sends the reference signal power from the network device side to the terminal device, and the terminal device receives the reference signal power from the network device.

[0097] The power of the reference signal can be obtained through higher-level configuration parameters.

[0098] S4. The terminal device determines the downlink path loss between the network device and the terminal device based on RSRP and reference signal power.

[0099] It should be noted that, in Figure 5In the illustrated process, S2 can be executed first, followed by S3; or S3 can be executed first, followed by S2; or S2 and S3 can be executed simultaneously. That is, the terminal device can receive the reference signal, measure the reference signal to obtain the RSRP, and then acquire the reference signal power indicated by the network device; alternatively, it can acquire the reference signal power indicated by the network device and then measure the reference signal to obtain the RSRP; or it can measure the reference signal power indicated by the network device while simultaneously acquiring the RSRP.

[0100] As an example, the downlink path loss between the network device and the terminal device can satisfy the following formula:

[0101] PL D =P RSP_1 -P HRSRP (4)

[0102] Among them, PL D P represents the downlink path loss between the network device and the terminal device. RSP_1 P represents the reference signal power on the network device side. HRSRP This represents the higher-layer filtering RSRP on the terminal device side. Where P... RSP_1 It is configured by the network device, P HRSRP It is obtained based on RSRP.

[0103] Referring to the aforementioned method for determining downlink path loss, the sidelink path loss can satisfy the following formula:

[0104] PL SL =P RSP_2 -P HRSRP (5)

[0105] Among them, pL SL P represents the side path loss between the transmitting and receiving devices. RSP_2 P represents the reference signal power on the transmitting device side. HRSRP This refers to the higher layer filter RSRP on the receiving device side.

[0106] However, unlike methods that control transmit power based on downlink path loss, side-link communication involves direct communication between two terminal devices. Therefore, the method of configuring reference signal power by the network device to obtain path loss is no longer applicable to this scenario. Currently, there is no feasible method for determining side-link path loss.

[0107] In view of this, in order to determine the lateral path loss, this application proposes a method and apparatus for determining the lateral path loss between two terminal devices, thereby enabling the control of the transmit power of the terminal devices based on the lateral path loss to improve communication performance.

[0108] Please see Figure 6 This is a flowchart illustrating a method for determining path loss according to an embodiment of this application. This method can be applied to D2D side-by-side communication scenarios, including NR D2D and LTE D2D side-by-side communication scenarios; or, it can be applied to V2X side-by-side communication scenarios, including NR V2X and LTE V2X side-by-side communication scenarios. Alternatively, it can be applied to other scenarios or other communication systems, specifically not limited to V2X systems. For example, this method can be applied to... Figure 4 The illustration shows a side-by-side communication scenario of the NR V2X system 400. The following description uses the NR V2X system 400 as an example to illustrate the method for determining path loss provided in this application embodiment. The first terminal device mentioned below can be... Figure 4 Terminal device 2 in the middle, the second terminal device can be Figure 4 Terminal device 3 in the middle.

[0109] S601: The first terminal device sends a first reference signal to the second terminal device.

[0110] The first terminal device sends a first reference signal to the second terminal device. This first reference signal can be sent along with control signaling or data. Specifically, sending the first reference signal along with control information means that the first reference signal is sent through the physical sidelink control channel (PSCCH); sending the first reference signal along with data means that the first reference signal is sent through the physical sidelinkshare channel (PSSCH).

[0111] For example, please see Figure 7 This is a schematic diagram of the structure of a physical resource block (PRB). Figure 7As shown, an RPB consists of 14 orthogonal frequency division multiplexing (OFDM) symbols. The first OFDM symbol is typically used for automatic gain control (AGC), and the last OFDM symbol is the gap (GAP), which usually does not transmit any data but can be used for handover between devices. The PSCCH and PSSCH channels are transmitted together. A portion of the subcarriers on the second to fourth OFDM symbols are used to carry the PSCCH, while the subcarriers on the fifth to thirteenth OFDM symbols, and the subcarriers on the second to fourth OFDM symbols excluding those used for PSCCH, are used to carry the PSSCH. The PSSCH consists of a demodulation reference signal (DMRS) and data. If the first reference signal is transmitted along with the data, then the DMRS in the PSSCH can be the first reference signal, meaning that the DMRS can be used for RSRP measurement. The PSSCH can be scheduled periodically, semi-persistently (SPS) or aperiodically, and the embodiments of this application do not limit this.

[0112] S602: The first terminal device obtains the first filtered power based on the transmission power of the first reference signal.

[0113] After sending a first reference signal to a second terminal device, the first terminal device can obtain a first filtered power for calculating path loss based on one or more of a first filtering coefficient, the transmission power of the first reference signal, or a third filtered power. The third filtered power is either obtained by the first terminal device based on the transmission power of the second reference signal, or it can be the transmission power of the first reference signal. For example, if the first reference signal is the first reference signal sent by the first terminal device to the second terminal device for the first time, the third filtered power is initialized to the transmission power of the first reference signal, and the first terminal device can determine the first filtered power based on the first filtering coefficient and the transmission power of the first reference signal. If the first reference signal is not the first reference signal sent by the first terminal device to the second terminal device for the first time, the third filtered power is the filtered power obtained by the first terminal device based on the transmission power of the second reference signal, and the first terminal device can determine the first filtered power based on the first filtering coefficient, the transmission power of the first reference signal, and the third filtered power. The second reference signal is the reference signal most recently sent by the first terminal device to the second terminal device before sending the first reference signal.

[0114] The reference signal first sent by the first terminal device to the second terminal device can be understood as the first reference signal sent by the first terminal device to the second terminal device after the triggering condition for data transmission is met. The triggering condition for data transmission may be, for example, that the network device 1 instructs the first terminal device to send information to the second terminal device through downlink control information (DCI); or it may be that the first terminal device actively sends data to the second terminal device, etc.

[0115] In one possible implementation, the first terminal device can determine the transmit power of the first reference signal based on higher-layer configuration parameters, which may be configuration parameters of the RRC layer.

[0116] The first filter coefficient is a parameter used to determine the reference signal power on the transmitting device (such as the first terminal device) side (for example, the reference signal power on the first terminal device side is denoted as the first filter power). In other words, the first filter coefficient is used to determine P in formula (5). RSP_2 The parameters. The first filter coefficient can be configured by network device 1, obtained from the configuration information of the resource pool, or configured by the first terminal device. These three methods are described below.

[0117] Method 1: The first filter coefficient is configured by network device 1.

[0118] For example, network device 1 (such as a base station) can configure a first filtering coefficient for the first terminal device via higher-layer signaling. In this way, the first terminal device can determine the first filtering power based on the higher-layer signaling. The higher-layer signaling can be, for example, a media access control (MAC) control element (CE) or RRC signaling. In method 1 described above, the first terminal device can determine the first filtering power based on the first filtering coefficient configured by network device 1, thereby enabling the determination of the side-path loss.

[0119] Method 2: The first filter coefficient is obtained from the configuration information of the resource pool.

[0120] This resource pool is, for example, a sidelink resource pool. For instance, a first filtering coefficient can be pre-configured in the sidelink resource pool. The second terminal device can then obtain this first filtering coefficient from the configuration information of the sidelink resource pool and determine the first filtering power based on it. During this process, the first terminal device does not need to interact with network device 1, thereby saving network resources and reducing communication complexity.

[0121] The sidelink resource pool can include time-frequency resources used for sidelink communication. The configuration information of this sidelink resource pool may include some common configuration parameters, such as the size of the subchannel or the subcarrier spacing. A terminal device can be configured with multiple sidelink resource pools, and the same sidelink resource pool can correspond to multiple sidelinks. A sidelink can only be established between two terminal devices when both are configured with the same sidelink resource pool.

[0122] In method 2 described above, the first filtering coefficient is obtained from the configuration information of the resource pool. The first terminal device can determine the first filtering power based on the first filtering coefficient, thereby enabling the determination of the sidelink path loss. The implementation process is simple and easy to implement. For example, a sidelink resource pool is configured with one first filtering coefficient. All UEs using this sidelink resource pool can use this first filtering coefficient to determine the path loss, without requiring network device 1 or the UE to configure the first filtering coefficient themselves. This reduces the interaction process (e.g., the network device sending the configured first filtering coefficient to the first terminal device), making the implementation simple and easy to implement.

[0123] Method 3: The first filter coefficient is configured by the first terminal device.

[0124] The first terminal device can configure the first filtering coefficient itself to determine the side link path loss. Method 3 is applicable to scenarios where network device 1 is not present, and also to scenarios where the first filtering coefficient is not configured in the resource pool. This means that when the first terminal device, as a transmitting device, needs to determine the side link path loss, it does not need to obtain the first filtering coefficient with the help of a third party (such as network device 1 or resource pool). It can configure the first filtering coefficient itself to determine the side link path loss, and it is highly adaptable and flexible.

[0125] In one possible implementation, the first terminal device stores a first initial filter coefficient, which is used to determine the reference signal power (i.e., P) in formula (5). RSP_2For example, the first initial filtering coefficient may be a parameter pre-configured in the first terminal device at the factory. In this case, the first filtering coefficient is configured by the network device 1, which can be understood as the network device 1 directly configuring the first filtering coefficient for the first terminal device, or as the network device 1 sending parameter information (e.g., multiplier or increment values) to the first terminal device so that the first terminal device determines the first filtering coefficient based on the first initial filtering coefficient and / or the parameter information; similarly, the first filtering coefficient is obtained from the resource pool, which can be understood as the first terminal device obtaining the first filtering coefficient from the resource pool, or as the first terminal device obtaining parameter information from the resource pool and then determining the first filtering coefficient based on the parameter information and / or the first initial filtering coefficient; the first filtering coefficient is configured by the first terminal device, which can be understood as the first terminal device configuring the first filtering coefficient itself, or as the first terminal device configuring the parameter information itself and then determining the first filtering coefficient based on the parameter information and / or the first initial filtering coefficient.

[0126] In another possible implementation, the first filtering coefficient can be a first initial filtering coefficient. This means that the first terminal device can determine the first filtering power based on the first initial filtering coefficient, without requiring configuration by the network device 1 or the first terminal device, and without obtaining it from the resource pool, which simplifies the implementation process and makes it easy to implement.

[0127] In one possible implementation, the first terminal device can filter the transmit power of the first reference signal according to a first filtering coefficient, such as high-level filtering, to obtain a first filtered power. High-level filtering refers to filtering at a higher level (such as the RRC layer).

[0128] As an example, the first terminal device performs high-level filtering on the transmit power of the first reference signal, and the resulting first filtered power can satisfy the following formula:

[0129] P n = (1-b)×P n-1 +b×L n (6)

[0130] Among them, P n P represents the first filter power. n-1 This indicates the power of the third filter. L n This represents the transmit power of the first reference signal. b represents the weighting coefficient, and the value of b is related to the first filter coefficient. For example, if the first filter coefficient is denoted as q, then b = 1 / 2. (q / 4 ). n indicates that the first reference signal is transmitted for the nth time, and n is an integer greater than or equal to 1.

[0131] In formula (6), when the first reference signal is the reference signal sent by the first terminal device to the second terminal device for the first time (i.e., n equals 1), the third filter power is the transmission power of the first reference signal, i.e., P0 = L1. In this case, it can be seen that the first filter power is the transmission power of the first reference signal, i.e., P1 = L1.

[0132] In the above embodiments, the first terminal device uses high-layer filtering to calculate the first filter power. As can be seen from formula (6), the first filter power is the instantaneous value of the transmission power of the most recent transmitted reference signal (i.e., L). n ) and the filter power (i.e., P) obtained from the previous high-level filtering calculation. n-1 The path loss is determined jointly, which avoids the problem of large errors in the calculated path loss due to a sudden increase or decrease in the instantaneous value of the transmission power at a certain moment. Therefore, the path loss between the two terminal devices can be estimated more accurately.

[0133] It should be noted that in the embodiments of this application, "first filter power" is only an exemplary name. In specific implementations, it can also be named other names, such as power, high-level filter power, or reference signal power, etc. The name itself does not constitute a limitation on the technical features.

[0134] S603: The second terminal device receives the second filtered power obtained by the first terminal device based on the received power of the first reference signal.

[0135] After receiving a first reference signal from a first terminal device, the second terminal device can obtain a second filtered power for calculating path loss based on one or more of a second filtering coefficient, the received power of the first reference signal, or a fourth filtered power. The fourth filtered power is obtained by the second terminal device based on the received power of the second reference signal, or it can be the received power of the first reference signal. For example, if the first reference signal is the first reference signal received by the second terminal device from the first terminal device, the fourth filtered power is initialized to the received power of the first reference signal, and the second terminal device can determine the second filtered power based on the second filtering coefficient and the received power of the first reference signal. If the first reference signal is not the first reference signal received by the second terminal device from the first terminal device, the fourth filtered power is the filtered power obtained by the second terminal device based on the received power of the second reference signal, and the second terminal device can determine the second filtered power based on the second filtering coefficient, the received power of the first reference signal, and the fourth filtered power. The second reference signal is the most recent reference signal received by the second terminal device from the first terminal device before receiving the first reference signal.

[0136] In one possible implementation, the second terminal device can measure the received first reference signal to obtain the received power of the first reference signal. Figure 7 For example, the first reference signal is DMRS. The second terminal device can calculate the received power of the resource units of DMRS carried on PSSCH, and then perform a linear average calculation on the received power of the resource units of all DMRS to obtain the received power of the first reference signal.

[0137] The second filter coefficient is a parameter used to determine the higher layer filtering RSRP (e.g., denoted as the second filter power) on the receiving device (such as the second terminal device) side. In other words, the second filter coefficient is used to determine P in formula (5). HRSRP The parameters. This second filtering coefficient can be configured by network device 1, obtained from the configuration information of the resource pool, or configured by the first terminal device. These three methods will be described in detail below.

[0138] Method 1: The second filter coefficient is configured by network device 1.

[0139] For example, network device 1 (such as a base station) can configure a second filtering coefficient for the second terminal device through higher-layer signaling. In this way, the second terminal device can determine the second filtering power based on the second filtering coefficient configured by network device 1. The higher-layer signaling includes CE or RRC signaling at the MAC layer. In method 1 described above, the second terminal device can determine the second filtering power based on the second filtering coefficient configured by network device 1, thus enabling the determination of the side-path loss.

[0140] Method 2: The second filter coefficient is obtained from the configuration information of the resource pool.

[0141] This resource pool is, for example, a sidelink resource pool. For instance, the second filtering coefficient can be pre-configured in the sidelink resource pool. In this way, the second terminal device can obtain the second filtering coefficient from the configuration information of the sidelink resource pool and then determine the second filtering power based on the second filtering coefficient. During this process, the second terminal device does not need to interact with network device 1, thereby saving network resources and reducing communication complexity.

[0142] Method 3: The second filter coefficient is configured by the first terminal device.

[0143] The first terminal device can configure a second filtering coefficient for the second terminal device to determine the path loss of the opposite link. Method 3 is applicable to scenarios where network device 1 is not present, and also to scenarios where the resource pool does not have a configured second filtering coefficient. This means that it is not necessary to obtain the second filtering coefficient with the help of a third party (such as network device 1 or resource pool). The path loss of the opposite link can be determined based on the second filtering coefficient configured by the first terminal device, which is highly adaptable and flexible.

[0144] When the second filter coefficient is configured by the first terminal device, before S603, the second terminal device receives second indication information from the first terminal device, which is used to indicate the second filter coefficient.

[0145] In one possible implementation, the second terminal device stores a second initial filter coefficient, which is used to determine the reference signal power (i.e., P) in formula (5). HRSRP For example, the second initial filtering coefficient can be a parameter pre-configured in the second terminal device at the factory. In this case, the second filtering coefficient is configured by network device 1, which can be understood as network device 1 directly configuring the second filtering coefficient for the second terminal device, or network device 1 sending parameter information (e.g., multiplier or increment value, etc.) to the second terminal device so that the second terminal device determines the second filtering coefficient based on the second initial filtering coefficient and / or the parameter information; similarly, the second filtering coefficient is obtained from the resource pool, which can be understood as the second terminal device obtaining the second filtering coefficient from the resource pool, or the second terminal device obtaining parameter information from the resource pool and then determining the second filtering coefficient based on the parameter information and / or the second initial filtering coefficient; the second filtering coefficient is configured by the second terminal device, which can be understood as the first terminal device configuring the second filtering coefficient for the second terminal device, or the first terminal device configuring parameter information for the second terminal device, and then the second terminal device determining the second filtering coefficient based on the parameter information and / or the second initial filtering coefficient.

[0146] In another possible implementation, the second filtering coefficient can be a second initial filtering coefficient. This means that the second terminal device can determine the second filtering power based on the second initial filtering coefficient, without requiring configuration by the network device 1 or the first terminal device, and without obtaining it from the resource pool, thus simplifying the implementation process and making it easy to implement.

[0147] In one possible implementation, if the first filtering coefficient is configured by network device 1, then the second filtering coefficient is also configured by network device 1; or, if the first filtering coefficient is obtained from the configuration information of the resource pool, then the second filtering coefficient is also obtained from the configuration information of the resource pool; or, if the first filtering coefficient is configured by the first terminal device, then the second filtering coefficient is also configured by the first terminal device; or, if the first filtering coefficient is a first initial filtering coefficient, then the second filtering coefficient is a second initial filtering coefficient.

[0148] In one possible implementation, the second terminal device can filter the received power of the first reference signal according to the second filtering coefficient, for example, through high-level filtering, to obtain the second filtered power. High-level filtering refers to filtering at a higher level (such as the RRC layer).

[0149] As an example, the second terminal device performs high-level filtering on the received power of the first reference signal, and the resulting first filtered power can satisfy the following formula:

[0150] F n = (1-a)×F n-1 +a×M n (7)

[0151] Among them, F n This indicates the second filter power. F n-1 This indicates the power of the fourth filter. M n This represents the received power of the first reference signal. 'a' represents the weighting coefficient, and its value is related to the second filter coefficient. For example, if the first filter coefficient is denoted as k, then b = 1 / 2. (k / 4) n indicates that the first reference signal is transmitted for the nth time, and n is an integer greater than or equal to 1.

[0152] In formula (7), when the first reference signal is the reference signal received by the second terminal device from the first terminal device for the first time (i.e., n equals 1), the fourth filter power is the received power of the first reference signal, i.e., F0 = M1. In this case, it can be seen that the second filter power is the received power of the first reference signal, i.e., F1 = M1.

[0153] In one possible implementation, if no first filter coefficient is configured for the transmitting device (such as the first terminal device) to determine the first filter power, the first filter coefficient can be assumed to be equal to the second filter coefficient, i.e., q = k.

[0154] In the above embodiments, when the second terminal device calculates the second filter power using high-layer filtering, it can be seen from formula (7) that the second filter power is the instantaneous value of the received power of the most recent received reference signal (i.e., M). n) and the filter power (i.e., F) obtained from the previous high-level filtering calculation. n-1 The path loss is determined jointly, which avoids the problem of large errors in the calculated path loss due to a sudden increase or decrease in the instantaneous value of the received power at a certain moment. Therefore, the path loss between the two terminal devices can be estimated more accurately.

[0155] It should be noted that in the embodiments of this application, "second filter power" is only an exemplary name. In specific implementations, it can also be named other names, such as power, high-level filter power, or high-level filter RSRP, etc.

[0156] S604: The second terminal device sends a first indication message to the first terminal device, wherein the first indication message is used to indicate the second filter power.

[0157] After obtaining the second filtered power based on the received power of the first reference signal, the second terminal device sends a first indication message to the first terminal device to indicate the second filtered power. The first indication message may be higher-layer signaling, such as CE or RRC signaling of the MAC layer.

[0158] It should be noted that the second terminal device may periodically send the first indication information to the first terminal device, or it may send the first indication information to the first terminal device after certain conditions are met (such as determining the second filtering power, or receiving a request message from the first terminal device to request the acquisition of the second filtering power).

[0159] For example, the second terminal device can quantize the second filter power according to Table 1 to obtain a quantized value, and send the quantized value to the first terminal device via higher-layer signaling. After receiving the quantized value, the first terminal device can determine the second filter power corresponding to the quantized value according to Table 1. For example, when the second filter power is less than -156 dBm, the quantized value obtained by quantizing the second filter power is RSRP_0. As another example, when the second filter power is less than -155 dBm and greater than or equal to -156 dBm, the quantized value obtained by quantizing the second filter power is RSRP_i. Specific mapping relationships can be found in Table 1, and will not be listed here. It should be noted that the “…” in Table 1 indicates that the second filter power increases accordingly as the quantization value number increases; for example, RSRP_4 corresponds to -153≤PSSCH-RSRP<-152, then RSRP_5 corresponds to -152≤PSSCH-RSRP<-153; similarly, it can be deduced that RSRP_123 corresponds to -34≤PSSCH-RSRP<-33, then RSRP_122 corresponds to -35≤PSSCH-RSRP<-34.

[0160] Quantized value Second filter power (dBm) RSRP_0 PSSCH-RSRP<-156 RSRP_1 -156≤PSSCH-RSRP<-155 RSRP_2 -155≤PSSCH-RSRP<-154 RSRP_3 -154≤PSSCH-RSRP<-153 RSRP_4 -153≤PSSCH-RSRP<-152 … … RSRP_123 -34≤PSSCH-RSRP<-33 RSRP_124 -33≤PSSCH-RSRP<-32 RSRP_125 -32≤PSSCH-RSRP<-31 RSRP_126 -31≤PSSCH-RSRP<-30 RSRP_127 -30≤PSSCH-RSRP

[0161] The second terminal device can reduce data transmission volume and save network resources by quantizing the second filter power and then instructing the quantized value to the first terminal device.

[0162] S605: After receiving the first instruction information, the first terminal device determines the path loss between the first terminal device and the second terminal device based on the first filter power and the second filter power.

[0163] After obtaining the first filter power and the second filter power, the first terminal device can determine the path loss between the first terminal device and the second terminal device.

[0164] As an example, the path loss between the first terminal device and the second terminal device is the difference between the first filter power and the second filter power, which can satisfy, for example, formula (8). In this case, the path loss between the first terminal device and the second terminal device is measured in decibels (dB).

[0165] PL SL =P n -F n (8)

[0166] Among them, PL SL P represents the path loss between the first terminal device and the second terminal device. n F represents the first filter power. n The second filter power is represented by n, where n represents the first reference signal being transmitted for the nth time, and n is an integer greater than or equal to 1.

[0167] As another example, the path loss between the first terminal device and the second terminal device is the ratio between the first filter power and the second filter power, which can satisfy, for example, formula (9).

[0168] PL SL =P n / F n (9)

[0169] Among them, PL SL P represents the path loss between the first terminal device and the second terminal device. n F represents the first filter power. n The second filter power is represented by n, where n represents the first reference signal being transmitted for the nth time, and n is an integer greater than or equal to 1.

[0170] It should be noted that, in Figure 6In the illustrated method flow, S602 can be executed first, followed by S603; or S603 can be executed first, followed by S602; or S602 and S603 can be executed simultaneously. That is, the second terminal device can determine the second filter power after the first terminal device has determined the first filter power; or the second terminal device can determine the second filter power before the first terminal device determines the first filter power; or the first terminal device and the second terminal device can determine the first filter power and the second filter power simultaneously, respectively. This application embodiment does not limit this to any particular method.

[0171] In the above embodiments of this application, the first terminal device obtains a first filtered power based on the transmit power of the first reference signal, and the second terminal device obtains a second filtered power based on the receive power of the first reference signal. The obtained second filtered power is then indicated to the first terminal device. The first terminal device can then determine the side-path loss between itself and the second terminal device based on the first and second filtered power. Since the first filtered power is not configured by the network device but is calculated by the first terminal device based on its actual transmit power of the reference signal, the path loss between the two terminal devices can be estimated more accurately.

[0172] Please see Figure 8 This is a flowchart illustrating another method for determining path loss provided in an embodiment of this application. This method can be applied to D2D side-by-side communication scenarios, including NR D2D and LTE D2D side-by-side communication scenarios; or it can be applied to V2X side-by-side communication scenarios, including NR V2X and LTE V2X side-by-side communication scenarios. Alternatively, it can be applied to other scenarios or other communication systems, specifically without limitation to V2X systems. For example, this method can be applied to... Figure 4 The illustration shows a side-by-side communication scenario of the NR V2X system 400. The following description uses the NR V2X system 400 as an example to illustrate the method for determining path loss provided in this application embodiment. The first terminal device mentioned below can be... Figure 4 Terminal device 2 in the middle, the second terminal device can be Figure 4 Terminal device 3 in the middle.

[0173] S801: The first terminal device sends a first reference signal to the second terminal device.

[0174] S802: After receiving the first reference signal sent by the first terminal device, the second terminal device obtains the second filter power based on the received power of the first reference signal.

[0175] After receiving a first reference signal from a first terminal device, the second terminal device can obtain a second filtering power for calculating path loss based on at least one of a second filtering coefficient, the received power of the first reference signal, or a fourth filtering power. The fourth filtering power is either obtained by the second terminal device based on the received power of the second reference signal or the received power of the first reference signal. For example, when the first reference signal is the first time the second terminal device receives a reference signal from the first terminal device, the third filtering power can be the received power of the first reference signal; when the first reference signal is not the first time the second terminal device receives a reference signal from the first terminal device, the third filtering power can be the filtering power obtained by the second terminal device based on the received power of the second reference signal. The second reference signal is the reference signal received by the second terminal device from the first terminal device before receiving the first reference signal.

[0176] In one possible implementation, the second terminal device can measure the received first reference signal to obtain the received power of the first reference signal. Figure 7 For example, the first reference signal is DMRS. The second terminal device can calculate the received power of the resource units of DMRS carried on PSSCH, and then perform a linear average calculation on the received power of the resource units of all DMRS to obtain the received power of the first reference signal.

[0177] The second filtering coefficient is used to determine the reference signal power (denoted as the second filtering power) on the receiving device (such as the second terminal device). This second filtering coefficient can be a higher-layer filtering coefficient or a weighting coefficient; this embodiment does not limit its application. The second filtering coefficient can be configured by the network device 1, obtained from the resource pool configuration information, or configured by the first terminal device. These three methods will be described in detail below.

[0178] Method 1: The second filter coefficient is configured by network device 1.

[0179] For example, network device 1 (such as a base station) can configure a second filtering coefficient for a second terminal device through higher-layer signaling. In this way, the second terminal device can determine the second filtering power based on the second filtering coefficient configured by network device 1. The higher-layer signaling includes CE or RRC signaling at the MAC layer.

[0180] Method 2: The second filter coefficient is obtained from the configuration information of the resource pool.

[0181] This resource pool is, for example, a sidelink resource pool. For instance, the second filtering coefficient can be pre-configured in the sidelink resource pool. In this way, the second terminal device can obtain the second filtering coefficient from the configuration information of the sidelink resource pool and then determine the second filtering power based on the second filtering coefficient. During this process, the second terminal device does not need to interact with network device 1, thereby saving network resources and reducing communication complexity.

[0182] Method 3: The second filter coefficient is configured by the first terminal device.

[0183] The first terminal device can configure a second filtering coefficient for the second terminal device to determine the path loss of the opposite link. Method 3 is applicable to scenarios where network device 1 is absent, and also to scenarios where the resource pool does not have a configured second filtering coefficient. This means that it is not necessary to obtain the second filtering coefficient through a third party (such as network device 1 or the resource pool); the path loss of the opposite link can be determined based on the second filtering coefficient configured by the first terminal device, demonstrating strong adaptability and high flexibility.

[0184] When the second filter coefficient is configured by the first terminal device, before S803, the second terminal device receives second indication information from the first terminal device, which is used to indicate the second filter coefficient.

[0185] In one possible implementation, the second terminal device stores a second initial filter coefficient, which is used to determine the reference signal power (i.e., P) in formula (5). HRSRP For example, the second initial filtering coefficient can be a parameter pre-configured in the second terminal device at the factory. In this case, the second filtering coefficient is configured by network device 1, which can be understood as network device 1 directly configuring the second filtering coefficient for the second terminal device, or network device 1 sending parameter information (e.g., multiplier or increment value, etc.) to the second terminal device so that the second terminal device determines the second filtering coefficient based on the second initial filtering coefficient and / or the parameter information; similarly, the second filtering coefficient is obtained from the resource pool, which can be understood as the second terminal device obtaining the second filtering coefficient from the resource pool, or the second terminal device obtaining parameter information from the resource pool and then determining the second filtering coefficient based on the parameter information and / or the second initial filtering coefficient; the second filtering coefficient is configured by the second terminal device, which can be understood as the first terminal device configuring the second filtering coefficient for the second terminal device, or the first terminal device configuring parameter information for the second terminal device, and then the second terminal device determining the second filtering coefficient based on the parameter information and / or the second initial filtering coefficient.

[0186] In another possible implementation, the second filtering coefficient can be a second initial filtering coefficient. This means that the second terminal device can determine the second filtering power based on the second initial filtering coefficient, without requiring configuration by the network device 1 or the first terminal device, and without obtaining it from the resource pool, thus simplifying the implementation process and making it easy to implement.

[0187] In one possible implementation, the second terminal device can filter the received power of the first reference signal according to the second filtering coefficient, for example, through high-level filtering, to obtain the second filtered power. High-level filtering refers to filtering at a higher level (such as the RRC layer).

[0188] As an example, the second terminal device performs high-level filtering on the received power of the first reference signal, and the resulting first filtered power can satisfy formula (7).

[0189] In formula (7), when the first reference signal is transmitted for the first time (i.e., n equals 1), the fourth filter power is the received power of the first reference signal, i.e., F0 = M1. In this case, it can be seen that the second filter power is the received power of the first reference signal, i.e., F1 = M1.

[0190] In the above embodiments, when the second terminal device calculates the second filter power using high-layer filtering, since the second filter power is determined by the instantaneous value of the received power of the most recent received reference signal and the filter power calculated by the previous high-layer filtering, the problem of large path loss error caused by the instantaneous value of the received power suddenly being too large or too small at a certain moment can be avoided. Therefore, the path loss between the two terminal devices can be estimated more accurately.

[0191] S803: The second terminal device sends a first indication message to the first terminal device, the first indication message being used to indicate the second filter power.

[0192] After obtaining the second filtered power based on the received power of the first reference signal, the second terminal device sends first indication information to the first terminal device to indicate the second filtered power. This first indication information can be higher-layer signaling, such as CE or RRC signaling at the MAC layer. The specific implementation of S803 is the same as described above. Figure 6 The implementation method of S604 is the same, and the implementation method described in S604 can be referred to, and will not be repeated here.

[0193] S804: After receiving the first instruction information, the first terminal device determines the path loss between the first terminal device and the second terminal device based on the transmission power of the first reference signal and the second filtering power.

[0194] In one possible implementation, the first terminal device may determine the transmission power of the first reference signal based on higher-level configuration parameters.

[0195] As an example, the path loss between the first terminal device and the second terminal device is the difference between the transmit power of the first reference signal and the second filter power, which can satisfy, for example, formula (8). In this case, the path loss between the first terminal device and the second terminal device is measured in dB.

[0196] As another example, the path loss between the first terminal device and the second terminal device is the ratio between the transmission power of the first reference signal and the second filter power, which can satisfy, for example, formula (9).

[0197] In the above embodiments of this application, the second terminal device obtains a second filtered power based on the received power of the first reference signal and instructs the first terminal device on the obtained second filtered power. Then, the first terminal device can determine the side-path loss between the first terminal device and the second terminal device based on the transmitted power of the first reference signal and the second filtered power. Since the transmitted power of the first reference signal can be determined from the higher-layer configuration parameters, there is no need to configure the first filtering coefficient, nor is there any additional overhead. Thus, while being able to estimate the path loss between the two terminal devices, overhead is reduced, making the implementation simple and easy to implement.

[0198] Based on the same technical concept as the method embodiments, this application provides an apparatus for determining path loss. The structure of the apparatus can be as follows: Figure 9 As shown, it includes a transceiver module 901 and a processing module 902.

[0199] The device 900 for determining path loss can be specifically used to implement... Figure 6 The method executed by the first terminal device in the embodiment. For example, the device 900 may be a vehicle (such as terminal device 2) in the NR V2X system 400, or it may be an on-board module, on-board component, on-board chip, or on-board unit built into the vehicle. It should be understood that Figure 4 The vehicle shown is merely an example; the device 900 could also be an RSU, a smartphone, a smartwatch, or a tablet, etc., and this application embodiment does not limit this. The transceiver module 901 is used to send a first reference signal to the second terminal device; the processing module 902 is used to obtain a first filtered power based on the transmission power of the first reference signal; the transceiver module 902 is also used to receive first indication information from the second terminal device, which indicates a second filtered power, the second filtered power being the power determined based on the first reference signal; the processing module 902 is also used to determine the path loss between the first terminal device and the second terminal device based on the first filtered power and the second filtered power.

[0200] In another possible implementation, the first filtering power is obtained based on at least one of a first filtering coefficient, the transmission power of a first reference signal, or a third filtering power, wherein the third filtering power is obtained by the first terminal device based on the transmission power of a second reference signal, or the transmission power of the first reference signal, and the second reference signal is a reference signal sent by the first terminal device to the second terminal device before sending the first reference signal.

[0201] In another possible implementation, the first filtering coefficient is configured by the network device, obtained from the configuration information of the resource pool, configured by the first terminal device, or is a first initial filtering coefficient, which is a parameter configured at the factory.

[0202] In another possible implementation, when the first filter coefficient is configured by the first terminal device, the transceiver module 901 is further configured to send second indication information to the second terminal device, the second indication information being used to indicate the second filter coefficient, the second filter coefficient being used to determine the second filter power.

[0203] In another possible implementation, the processing module 902 is specifically used to filter the transmission power of the first reference signal to obtain a first filtered power.

[0204] In another possible implementation, the first filter power can satisfy formula (6).

[0205] In another possible implementation, when n equals 1, the third filter power is the transmit power of the first reference signal.

[0206] In another possible implementation, the path loss between the first terminal device and the second terminal device includes the difference between the first filter power and the second filter power, or the ratio of the first filter power to the second filter power.

[0207] In another possible implementation, the processing module 902 is further configured to determine the transmit power of the first reference signal based on higher-layer configuration parameters.

[0208] The module division in this application embodiment is illustrative and represents only one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional modules in the various embodiments of this application can be integrated into a single processor, exist as separate physical entities, or be integrated into a single module. The integrated modules described above can be implemented in hardware or as software functional modules. It is understood that the functions or implementations of the modules in the embodiments of this application can be further described in the relevant descriptions of the method embodiments.

[0209] In one possible implementation, the device 1000 for determining path loss can be as follows: Figure 10 As shown, the device 1000 can be a first terminal device, such as an RSU, a smartphone, a vehicle, an in-vehicle module, in-vehicle component, in-vehicle chip, or in-vehicle unit built into the vehicle. The device 1000 may include a processor 1001, a transceiver 1002, and a memory 1003. The transceiver module 901 can be the transceiver 1002, which can act as a transmitter when sending information and as a receiver when receiving information. The processing module 902 can be the processor 1001.

[0210] The processor 1001 can be a CPU or a digital processing unit, etc. The transceiver 1002 can be a communication interface, an interface circuit such as a transceiver circuit, or a transceiver chip, etc. The device 1000 also includes a memory 1003 for storing the program executed by the processor 1001. The memory 1003 can be non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), or it can be volatile memory, such as random-access memory (RAM). The memory 1003 can be any other medium capable of carrying or storing desired program code in the form of instructions or data structures, and accessible by a computer, but is not limited to this.

[0211] The processor 1001 is used to execute the program code stored in the memory 1003, specifically to perform the actions of the aforementioned processing module 902, which will not be described in detail here. The transceiver 1002 is specifically used to perform the actions of the aforementioned transceiver module 901, which will not be described in detail here.

[0212] This application embodiment does not limit the specific connection medium between the transceiver 1002, processor 1001, and memory 1003. This application embodiment... Figure 10 The memory 1003, processor 1001, and transceiver 1002 are connected via a bus 1004. Figure 10 The connections between other components are shown in bold lines only and are not intended to be limiting. Bus 1004 can be divided into address bus, data bus, control bus, etc. For ease of illustration, Figure 10 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0213] Based on the same technical concept as the method embodiments, this application provides an apparatus for determining path loss. The structure of the apparatus can be as follows: Figure 11 As shown, it includes a transceiver module 1101 and a processing module 1102.

[0214] The device 1100 for determining path loss can be specifically used to implement Figure 8 The method executed by the first terminal device in the embodiment. For example, the device 1100 may be a vehicle (such as terminal device 2) in the NR V2X system 400, or it may be an on-board module, on-board unit, on-board component, on-board chip, or on-board unit built into the vehicle. It should be understood that Figure 4 The vehicle shown is merely an example; the device 1100 could also be an RSU, smartphone, smartwatch, or tablet, etc., and this application embodiment does not limit it. The transceiver module 1101 is used to send a first reference signal to the second terminal device and receive first indication information from the second terminal device, the first indication information indicating a second filtering power, the second filtering power being the power determined based on the first reference signal. The processing module 1102 is used to determine the path loss between the first terminal device and the second terminal device based on the transmission power of the first reference signal and the second filtering power.

[0215] In another possible implementation, the transceiver module 1101 is further configured to send second indication information to the second terminal device, the second indication information being used to indicate the second filtering coefficient, and the second filtering coefficient being used to determine the second filtering power.

[0216] In another possible implementation, the processing module 1102 is further configured to determine the transmit power of the first reference signal based on higher-layer configuration parameters.

[0217] In another possible implementation, the path loss between the first terminal device and the second terminal device includes the difference between the transmission power of the first reference signal and the second filter power, or the ratio of the transmission power of the first reference signal to the second filter power.

[0218] The module division in this application embodiment is illustrative and represents only one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional modules in the various embodiments of this application can be integrated into a single processor, exist as separate physical entities, or be integrated into a single module. The integrated modules described above can be implemented in hardware or as software functional modules. It is understood that the functions or implementations of the modules in the embodiments of this application can be further described in the relevant descriptions of the method embodiments.

[0219] In one possible implementation, the device 1200 for determining path loss can be as follows: Figure 12 As shown, the device 1200 can be a first terminal device, such as an RSU, a smartphone, a vehicle, an in-vehicle module, in-vehicle component, in-vehicle chip, or in-vehicle unit built into the vehicle. The device 1200 may include a processor 1201, a transceiver 1202, and a memory 1203. The transceiver module 1101 can be the transceiver 1202, which can act as a transmitter when sending information and a receiver when receiving information. The processing module 1102 can be the processor 1201.

[0220] The processor 1201 can be a CPU or a digital processing unit, etc. The transceiver 1202 can be a communication interface, an interface circuit such as a transceiver circuit, or a transceiver chip, etc. The device 1200 also includes a memory 1203 for storing the program executed by the processor 1201. The memory 1203 can be non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), or it can be volatile memory, such as random-access memory (RAM). The memory 1203 can be any other medium capable of carrying or storing desired program code in the form of instructions or data structures, and accessible by a computer, but is not limited to this.

[0221] The processor 1201 is used to execute the program code stored in the memory 1203, specifically to perform the actions of the aforementioned processing module 1102, which will not be described in detail here. The transceiver 1202 is specifically used to perform the actions of the aforementioned transceiver module 1101, which will not be described in detail here.

[0222] This application embodiment does not limit the specific connection medium between the transceiver 1202, processor 1201, and memory 1203. This application embodiment... Figure 12 The memory 1203, processor 1201, and transceiver 1202 are connected via a bus 1204. Figure 12 The connections between other components are shown in thick lines only and are not intended to be limiting. The 1204 bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, Figure 12 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0223] Based on the same technical concept as the method embodiments, this application provides an apparatus for determining path loss. The structure of the apparatus can be as follows: Figure 13 As shown, it includes a transceiver module 1301 and a processing module 1302.

[0224] The device 1300 for determining path loss can be specifically used to implement... Figure 6 and Figure 8 The method executed by the second terminal device in the embodiments. For example, the device 1300 may be a vehicle (such as terminal device 3) in the NR V2X system 400, or it may be an on-board module, on-board unit, on-board component, on-board chip, or on-board unit built into the vehicle. It should be understood that Figure 4 The vehicle shown is merely an example; the device 1300 could also be an RSU, a smartphone, a smartwatch, or a tablet, etc., and this application embodiment does not limit this. The transceiver module 1301 is used to receive a first reference signal from the first terminal device; the processing module 1302 is used to obtain a second filtered power based on the received power of the first reference signal, the second filtered power being used to determine the path loss between the first terminal device and the second terminal device; the transceiver module 1301 is also used to send first indication information to the first terminal device, the first indication information being used to indicate the second filtered power.

[0225] In another possible implementation, the second filtering power is obtained based on at least one of a second filtering coefficient, the received power of the first reference signal, or a fourth filtering power, wherein the fourth filtering power is obtained by the second terminal device based on the received power of the second reference signal or the received power of the first reference signal, and the second reference signal is a reference signal received by the second terminal device before receiving the first reference signal.

[0226] In another possible implementation, the second filtering coefficient is configured by the network device, obtained from the configuration information of the resource pool, configured by the first terminal device, or is a second initial filtering coefficient, which is a parameter configured at the factory.

[0227] In another possible implementation, when the second filter coefficient is configured by the first terminal device, the transceiver module 1301 is further configured to receive second indication information from the first terminal device, the second indication information being used to indicate the second filter coefficient.

[0228] In another possible implementation, the processing module 1302 is specifically used to filter the received power of the first reference signal to obtain the second filtered power.

[0229] In another possible implementation, the second filter power can satisfy formula (7).

[0230] In another possible implementation, when n equals 1, the fourth filter power is the received power of the first reference signal.

[0231] In another possible implementation, the processing module 1302 is further configured to measure the first reference signal to obtain the received power of the first reference signal.

[0232] The module division in this application embodiment is illustrative and represents only one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional modules in the various embodiments of this application can be integrated into a single processor, exist as separate physical entities, or be integrated into a single module. The integrated modules described above can be implemented in hardware or as software functional modules. It is understood that the functions or implementations of the modules in the embodiments of this application can be further described in the relevant descriptions of the method embodiments.

[0233] In one possible implementation, the device 1400 for determining path loss can be as follows: Figure 14 As shown, the device 1400 can be a second terminal device, such as an RSU, a smartphone, a vehicle, an in-vehicle module, in-vehicle component, in-vehicle chip, or in-vehicle unit built into the vehicle. The device 1400 may include a processor 1401, a transceiver 1402, and a memory 1403. The transceiver module 1301 can be the transceiver 1402; the transceiver 1402 can act as a transmitter when sending information and as a receiver when receiving information. The processing module 1302 can be the processor 1401.

[0234] The processor 1401 can be a CPU or a digital processing unit, etc. The transceiver 1402 can be a communication interface, an interface circuit such as a transceiver circuit, or a transceiver chip, etc. The device 1400 also includes a memory 1403 for storing the program executed by the processor 1401. The memory 1403 can be non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), or it can be volatile memory, such as random-access memory (RAM). The memory 1403 can be any other medium capable of carrying or storing desired program code in the form of instructions or data structures, and accessible by a computer, but is not limited to this.

[0235] The processor 1401 is used to execute the program code stored in the memory 1403, specifically to perform the actions of the aforementioned processing module 1302, which will not be described in detail here. The transceiver 1402 is specifically used to perform the actions of the aforementioned transceiver module 1301, which will not be described in detail here.

[0236] This application embodiment does not limit the specific connection medium between the transceiver 1402, processor 1401, and memory 1403. This application embodiment... Figure 14 The memory 1403, processor 1401, and transceiver 1402 are connected via a bus 1404. Figure 14 The connections between other components are shown in thick lines only and are not intended to be limiting. The 1404 bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, Figure 14 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0237] This application also provides a computer-readable storage medium for storing computer software instructions required to execute the processor, including a program required to execute the processor.

[0238] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0239] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0240] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0241] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0242] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the scope of protection of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for determining path loss, characterized in that, The method includes: The first terminal device sends a first reference signal and a second indication information to the second terminal device, wherein the second indication information is used to indicate the second filter coefficient. The first terminal device obtains the first filter power based on the transmission power of the first reference signal, the first filter coefficient, and the third filter power. The third filter power is obtained by the first terminal device based on the transmission power of the second reference signal. The second reference signal is a reference signal sent by the first terminal device to the second terminal device before transmitting the first reference signal. The first terminal device receives first indication information from the second terminal device, the first indication information being used to indicate a second filtering power, the second filtering power being a power determined based on the second filtering coefficient and the first reference signal; The first terminal device determines the path loss between the first terminal device and the second terminal device based on the first filter power and the second filter power.

2. The method according to claim 1, characterized in that, The first filtering coefficient is configured by the network device, or obtained from the configuration information of the resource pool, or configured by the first terminal device, or it is a first initial filtering coefficient, which is a parameter configured at the factory.

3. The method according to claim 1 or 2, characterized in that, The first filter power satisfies the following formula: P n =(1-b)×P n-1 +b×L n Among them, P n P represents the first filter power. n-1 L represents the third filter power. n The first reference signal is represented by its transmission power, b is represented by its weighting coefficient, the value of which is related to the first filtering coefficient, and n is represented by the first reference signal being transmitted for the nth time, where n is an integer greater than or equal to 1.

4. The method according to claim 3, characterized in that, When n equals 1, the third filter power is the transmission power of the first reference signal.

5. The method according to claim 1 or 2, characterized in that, The path loss between the first terminal device and the second terminal device includes the difference between the first filter power and the second filter power, or the ratio of the first filter power to the second filter power.

6. The method according to claim 1 or 2, characterized in that, The method further includes: The first terminal device determines the transmission power of the first reference signal based on the high-level configuration parameters.

7. A method for determining path loss, characterized in that, The method includes: The second terminal device receives a first reference signal and a second indication information from the first terminal device, wherein the second indication information is used to indicate the second filter coefficient. The second terminal device obtains a second filtering power based on the received power of the first reference signal and the second filtering coefficient. The second filtering power is used to determine the path loss between the first terminal device and the second terminal device. The second terminal device sends a first indication message to the first terminal device. The first indication message is used to indicate the second filtering power so that the first terminal device can determine the path loss between the first terminal device and the second terminal device based on the second filtering power and the first filtering power. The first filtering power is the filtering power obtained by the first terminal device based on the transmission power of the first reference signal, the first filtering coefficient, and the third filtering power. The third filtering power is obtained by the first terminal device based on the transmission power of the second reference signal. The second reference signal is the reference signal sent by the first terminal device to the second terminal device before sending the first reference signal.

8. The method according to claim 7, characterized in that, The second filtering power is obtained based on the second filtering coefficient, the received power of the first reference signal, and the fourth filtering power. The fourth filtering power is obtained by the second terminal device based on the received power of the second reference signal, which is a reference signal received by the second terminal device before receiving the first reference signal.

9. The method according to claim 7 or 8, characterized in that, The second terminal device obtains the second filtered power based on the received power of the first reference signal and the second filtered coefficient, including: The second terminal device filters the received power of the first reference signal according to the second filtering coefficient to obtain the second filtered power.

10. The method according to claim 9, characterized in that, The second filter power satisfies the following formula: F n =(1-a)×F n-1 +a×M n Among them, F n F represents the second filter power. n-1 M represents the fourth filter power. n The received power of the first reference signal is represented by , a represents the weighting coefficient, the value of which is related to the second filtering coefficient, and n represents that the first reference signal is transmitted for the nth time, where n is an integer greater than or equal to 1.

11. The method according to claim 10, characterized in that, When n equals 1, the fourth filter power is the received power of the first reference signal.

12. The method according to claim 7 or 8, characterized in that, The method further includes: The second terminal device measures the first reference signal to obtain the received power of the first reference signal.

13. A device for determining path loss, applied to a first terminal device, characterized in that, include: The transceiver module is used to send a first reference signal and a second indication information to the second terminal device, wherein the second indication information is used to indicate the second filter coefficient; The processing module is configured to obtain a first filtering power based on the transmission power of the first reference signal, a first filtering coefficient, and a third filtering power. The third filtering power is obtained by the first terminal device based on the transmission power of the second reference signal. The second reference signal is a reference signal sent by the first terminal device to the second terminal device before transmitting the first reference signal. The transceiver module is further configured to receive first indication information from the second terminal device, the first indication information being used to indicate a second filtering power, the second filtering power being a power determined based on the second filtering coefficient and the first reference signal; The processing module is further configured to determine the path loss between the first terminal device and the second terminal device based on the first filter power and the second filter power.

14. The apparatus according to claim 13, characterized in that, The first filtering coefficient is configured by the network device, or obtained from the configuration information of the resource pool, or configured by the first terminal device, or it is a first initial filtering coefficient, which is a parameter configured at the factory.

15. The apparatus according to claim 13 or 14, characterized in that, The first filter power satisfies the following formula: P n =(1-b)×P n-1 +b×L n Among them, P n P represents the first filter power. n-1 L represents the third filter power. n The first reference signal is represented by its transmission power, b is represented by its weighting coefficient, the value of which is related to the first filtering coefficient, and n is represented by the first reference signal being transmitted for the nth time, where n is an integer greater than or equal to 1.

16. The apparatus according to claim 15, characterized in that, When n equals 1, the third filter power is the transmission power of the first reference signal.

17. The apparatus according to claim 13 or 14, characterized in that, The path loss between the first terminal device and the second terminal device includes the difference between the first filter power and the second filter power, or the ratio of the first filter power to the second filter power.

18. The apparatus according to claim 13 or 14, characterized in that, The processing module is further used for: The transmission power of the first reference signal is determined based on the high-level configuration parameters.

19. A device for determining path loss, applied to a second terminal device, characterized in that, include: The transceiver module is used to receive a first reference signal and a second indication information from the first terminal device, wherein the second indication information is used to indicate a second filtering coefficient. The processing module is configured to obtain a second filtering power based on the received power of the first reference signal and the second filtering coefficient, wherein the second filtering power is used to determine the path loss between the first terminal device and the second terminal device. The transceiver module is further configured to send first indication information to the first terminal device. The first indication information is used to indicate the second filtering power, so that the first terminal device determines the path loss between the first terminal device and the second terminal device based on the second filtering power and the first filtering power. The first filtering power is the filtering power obtained by the first terminal device based on the transmission power of the first reference signal, the first filtering coefficient, and the third filtering power. The third filtering power is obtained by the first terminal device based on the transmission power of the second reference signal. The second reference signal is the reference signal sent by the first terminal device to the second terminal device before sending the first reference signal.

20. The apparatus according to claim 19, characterized in that, The second filtering power is obtained based on the second filtering coefficient, the received power of the first reference signal, and the fourth filtering power. The fourth filtering power is obtained by the second terminal device based on the received power of the second reference signal, which is a reference signal received by the second terminal device before receiving the first reference signal.

21. The apparatus according to claim 19 or 20, characterized in that, The processing module is specifically used for: The received power of the first reference signal is filtered according to the second filtering coefficient to obtain the second filtered power.

22. The apparatus according to claim 21, characterized in that, The second filter power satisfies the following formula: F n =(1-a)×F n-1 +a×M n Among them, F n F represents the second filter power. n-1 M represents the fourth filter power. n The received power of the first reference signal is represented by , a represents the weighting coefficient, the value of which is related to the second filtering coefficient, and n represents that the first reference signal is transmitted for the nth time, where n is an integer greater than or equal to 1.

23. The apparatus according to claim 22, characterized in that, When n equals 1, the fourth filter power is the received power of the first reference signal.

24. The apparatus according to claim 19 or 20, characterized in that, The processing module is further used for: The first reference signal is measured to obtain the received power of the first reference signal.

25. A communication device, characterized in that, Including processor and memory; The memory is used to store computer-executed instructions; The processor is configured to execute computer execution instructions stored in the memory, causing the communication device to perform the method as described in any one of claims 1 to 6, or causing the communication device to perform the method as described in any one of claims 7 to 12.

26. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when run on a computer, causes the computer to perform the method as described in any one of claims 1 to 6, or causes the computer to perform the method as described in any one of claims 7 to 12.

27. A system for determining path loss, characterized in that, Includes a first terminal device and a second terminal device; Wherein, the first terminal device is used to perform the method as described in any one of claims 1 to 6; The second terminal device is used to perform the method as described in any one of claims 7 to 12.

28. A computer program product, characterized in that, The computer program product is used to store computer instructions that, when executed, cause the method described in any one of claims 1 to 12 to be performed.

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