Resource selection method and terminal

Abstract

The present disclosure provides a resource selection method and a terminal, relating to the technical field of communication applications, which is applied to a first terminal, and includes: obtaining basic information sent from a second terminal, the basic information including a service transmission priority of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information; determining available resources available for service transmission from resource candidate candidates according to the service transmission priority and the signal reception power of the second terminal; and selecting a target resource required for service transmission from the available resources according to the service transmission priority of the first terminal.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority from Chinese Patent Application No. 201911089019.7, filed in China on November 8, 2019, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to the technical field of communication applications, and in particular to a resource selection method and a terminal. [Background technology]

[0003] In LTE-V2X (Long Term Evolution-Vehicle to Everything), for basic road safety applications, resource selection is performed by a sensing and semi-continuous scheduling method, and the difference in priority for each service is represented by the set sensing threshold. There are a total of eight levels of priority. 64 sensing power thresholds are set according to the eight possible priorities of the received control information and the eight possible priorities of the services to be transmitted from the own node. The higher the priority of the received control information or the priority of the services to be transmitted from the own node, the higher the sensing threshold. In this way, the higher the priority of the service, the more idling resources it senses the system has and the more available transmission resources it can obtain.

[0004] However, in the above-mentioned priority processing mechanism of LTE-V2X, the sensed power has a large jitter range due to the fast change of the wireless channel. When the system is congested, both high priority and low priority need to raise the threshold to realize resource selection. The final effect is that the raised threshold of high priority and low priority are the same, and the resource occupation and information transmission of the high priority service may not be reliably realized. In addition, there is no judgment of resource collision in LTE-V2X, and even if the occupied resources of terminals UE (User Equipment) with different priorities are identical or partially overlapped, no resource reselection is performed. Moreover, due to the counter processing mechanism of semi-continuous scheduling, the collision will continue to occur, and the resource collision will be avoided only after the next time resource reselection is performed. Therefore, the performance of the high priority UE cannot be guaranteed, and the low priority will not actively avoid the occupied resources of the high priority UE. Summary of the Invention [Problem to be solved by the invention]

[0005] The objective of the present disclosure is to provide a resource selection method and a terminal for solving the problem in the prior art that low priority UEs do not actively avoid the occupied resources of high priority UEs, and the performance of high priority UEs cannot be guaranteed. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, an embodiment of the present disclosure provides a resource selection method applied to a first terminal, and includes: obtaining basic information transmitted from a second terminal, the basic information including a priority of service transmission of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information; determining available resources available for service transmission among resource candidates based on the priority of service transmission of the second terminal and the signal reception power; and selecting a target resource required for service transmission from the available resources based on the priority of service transmission of the first terminal.

[0007] An embodiment of the present disclosure further provides a terminal, the terminal being a first terminal, including a transceiver, a memory, a processor, and a program stored in the memory and executable by the processor. The processor acquires basic information transmitted from a second terminal, the basic information including a priority of service transmission of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information, determines available resources available for service transmission among resource candidates based on the priority of service transmission of the second terminal and the signal reception power, and selects a target resource required for service transmission from the available resources based on the priority of service transmission of the first terminal.

[0008] An embodiment of the present disclosure further provides a terminal, the terminal being a first terminal, including: a first acquisition module for acquiring basic information transmitted from a second terminal, the basic information including a priority of service transmission of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information, a first determination module for determining an available resource available for service transmission among resource candidates based on the priority of service transmission of the second terminal and the signal reception power, and a first processing module for selecting a target resource required for service transmission from the available resources based on the priority of service transmission of the first terminal.

[0009] An embodiment of the present disclosure further provides a computer-readable storage medium having stored thereon a computer program that, when executed by a processor, causes the computer to implement the steps of the resource selection method described above. Effect of the Invention

[0010] In the above technical means of the embodiment of the present disclosure, available resources that can be used for service transmission are determined from among resource candidates based on the priority of service transmission and signal reception power of the second terminal, and target resources required for service transmission are selected from the available resources based on the priority of service transmission of the first terminal, thereby realizing resource preemption by high priority service transmission and ensuring the reliability of high priority service transmission. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating the occurrence of resource conflicts in the prior art. [Diagram 2] FIG. 2 is a diagram illustrating resource conflicts that may occur during a timing interval for periodic services in the prior art. [Diagram 3] FIG. 3 is a diagram showing the occurrence of resource conflicts with different priorities in the prior art. [Figure 4] FIG. 4 is a flowchart of a resource selection method according to an embodiment of the present disclosure. [Diagram 5] FIG. 5 is a diagram illustrating the determination of available resources in an embodiment of the present disclosure. [Figure 6] FIG. 6 is a second diagram illustrating the determination of available resources in an embodiment of the present disclosure. [Figure 7] FIG. 7 is a third diagram illustrating the determination of available resources in an embodiment of the present disclosure. [Figure 8] FIG. 8 is a diagram illustrating a resource selection window of a first terminal according to an embodiment of the present disclosure. [Figure 9] FIG. 9 is a diagram illustrating a resource selection window after determining available resources of a first terminal according to an embodiment of the present disclosure. [Figure 10] FIG. 10 is a block diagram illustrating a configuration of a terminal according to an embodiment of the present disclosure. [Figure 11] FIG. 11 is a diagram illustrating modules of a terminal according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] In order to clarify the technical problems, technical means and advantages of the present disclosure, the following detailed description will be provided with drawings and specific examples. In the following description, specific details of specific settings and components are provided only to fully understand the embodiments of the present disclosure. Therefore, it is obvious that those skilled in the art can make various changes and modifications to the embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, for clarity and conciseness, the description of known functions and structures is omitted.

[0013] It should be noted that, throughout the specification, the term "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic associated with an embodiment is included in at least one embodiment of the disclosure. Thus, the appearances of "in one embodiment" or "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment. Moreover, the particular feature, structure, or characteristic may be incorporated in any suitable manner in one or more embodiments.

[0014] In each embodiment of the present disclosure, the magnitude of the numbers of each process described below does not mean the order of execution, and the order of execution of each process is determined by its function and inherent logic, and it should be understood that this does not constitute any limitation on the implementation process of the embodiments of the present disclosure.

[0015] Also, in this text, the terms "system" and "network" can always be used interchangeably.

[0016] In the embodiments provided in the present application, "B corresponding to A" indicates that B and A are associated with each other, and B can be determined based on A. Note that determining B based on A does not mean determining B based only on A, and B may be determined based on A and / or other information.

[0017] At present, LTE-V2X technology is mainly targeted at basic road safety applications, and only supports broadcast transmission, not unicast and multicast transmission. When a transmitting UE needs to transmit a periodic service, it performs resource selection based on sensing and semi-persistent scheduling (SPS). That is, when a transport block (TB) arrives, the transmitting UE performs resource selection based on the sensing result. Once the resource selection is completed, even if a resource collision occurs for the selected resource before multiple transmissions of the TB, reselection is still not triggered. As shown in FIG. 1, even if a collision occurs between the first service transmission and the second service transmission, reselection is still not triggered. Also, as shown in FIG. 2, if a periodic service occupies the resource and continues to occupy it for a certain period of time using a counter, even if a resource collision occurs during that time, the UE does not reselect the resource, and it is not possible to realize the preemption of the resource by the high priority service transmission or the avoidance of the low priority service transmission for the high priority service transmission.

[0018] NR-V2X (New Radio-V2X) technology has not only periodic services, but also non-periodic services and mixed services, and supports broadcast transmission, as well as unicast and multicast transmission, making the transmission mechanism more complex. The resource selection mechanism in the prior art performs resource exclusion based on the Reference Signal Receiving Power (RSRP) value (those with RSRP higher than the RSRP threshold are excluded), and then selects the resources required for transmission from the resource candidates. After the exclusion, it is necessary to ensure that the proportion of resource candidates is equal to or greater than 20% of the total number of resources in the resource selection window. If it is less than 20%, the RSRP threshold needs to be raised, thereby raising the proportion of resource candidates until it meets the 20% condition.

[0019] However, considering that different services have different priorities, resource exclusion by RSRP alone cannot completely realize preemption of high priority and avoidance of low priority. As shown in Figure 3, UE1 receives TB at time n and needs to perform resource selection (the number of transmissions is 4). Because the RSRP value of high priority UE2 is less than the first threshold (i.e., the RSRP threshold), UE1 does not exclude the occupied resources of UE2 from the resource selection window. Therefore, the resource randomly selected by UE1 from the resource candidate set (including the occupied resources of UE2) may collide with the occupied resources of UE2 with high priority, which reduces the reliability of the high priority service.

[0020] Under the resource selection mechanism of LTE-V2X, when the resource exclusion by RSRP is performed, if the surplus resource is less than 20% of the resource selection window, the RSRP threshold needs to be raised. If the difference in priority is not considered, all UEs raise the threshold with resources less than 20%. Since the reserved resource of the high priority UE may be included in the resource candidate, the resource of the high priority UE and the occupied resource of the low priority UE collide, which affects the reliability of the high priority service. Therefore, based on the above, the present disclosure provides a resource selection method and a terminal that can realize the preemption of resources by the high priority UE, the active avoidance of the low priority UE from the occupied resource of the high priority UE, and the reselection of resources by the low priority UE when a collision occurs between the occupied resource and the occupied resource of the high priority UE, thereby ensuring the reliability of the transmission of high priority services.

[0021] Specifically, as shown in FIG. 4, an embodiment of the present disclosure provides a resource selection method applied to a first terminal, which includes the following steps:

[0022] In step 41, obtain basic information sent from a second terminal, the basic information including a priority of the service transmission of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information.

[0023] Specifically, the control information may also include the indicated time-frequency resource, where the signal received power may be RSRP or other parameters similar in function to RSRP, and is not limited thereto.

[0024] In step 42, an available resource available for service transmission is determined from among resource candidates according to the priority of service transmission of the second terminal and the signal reception power.

[0025] Specifically, the first terminal determines available resources available for the service transmission of the first terminal among resource candidates in a resource selection window based on the priority and RSRP of the service transmission of the second terminal, where the available resources may be a part of the resource candidates or all of the resource candidates.

[0026] In step 43, a target resource required for service transmission is selected from the available resources according to the priority of the service transmission of the first terminal.

[0027] Specifically, based on the priority of the service transmission of the first terminal, the first terminal may select preemption for the occupied resources of the low priority service transmission, or may avoid the occupied resources required for the high priority service transmission, to ensure the reliability of the high priority service transmission.

[0028] In an embodiment of the present disclosure, available resources that can be used for service transmission are determined from among resource candidates based on the priority of service transmission and signal reception power of the second terminal, and target resources required for service transmission are selected from the available resources based on the priority of service transmission of the first terminal, thereby realizing resource preemption by high priority service transmission and ensuring the reliability of high priority service transmission.

[0029] Optionally, in step 42, specifically, the steps include determining occupied resources required for the service transmission of the second terminal based on the priority of the service transmission of the second terminal and / or the signal reception power, and determining resources other than the occupied resources required for the service transmission of the second terminal from among the resource candidates as the available resources based on the occupied resources required for the service transmission of the second terminal.

[0030] Specifically, the first terminal may determine the occupied resources required for the service transmission of the second terminal based on the priority of the service transmission of the second terminal, or may determine the occupied resources required for the service transmission of the second terminal based on the priority of the service transmission of the second terminal and the signal reception power, that is, based on the priority of the service transmission of the second terminal and / or the signal reception power of the second terminal, it determines whether the occupied resources required for the service transmission of the second terminal are excluded from the resource candidates. If they are excluded, the resources other than the occupied resources required for the service transmission of the second terminal among the resource candidates are the available resources. If they are not excluded, the available resources include the occupied resources required for the service transmission of the second terminal.

[0031] Selectively determining the occupied resources required for the service transmission of the second terminal specifically includes, when a predetermined priority is set and the priority of the service transmission of the second terminal is equal to or higher than the predetermined priority, or when the predetermined priority is not set and the priority of the service transmission of the second terminal is equal to or higher than the priority of the service transmission of the first terminal, determining a time-frequency resource indicated in the control information among the resource candidates as the occupied resource required for the service transmission of the second terminal.

[0032] Specifically, the predetermined priority is the highest priority (e.g., Pmin) at which the RSRP threshold can be adjusted, and is set by higher layer signaling or is set and acquired in advance. If Pmin is set, after the first terminal has successfully decoded the received control information, the priority of the service transmission of the second terminal is compared with the priority of Pmin. If the priority of the second terminal in the control information is equal to or higher than the set priority Pmin, the time-frequency resource indicated in the control information among the resource candidates is determined as the occupied resource required for the service transmission of the second terminal. If Pmin is not set, after the first terminal has successfully decoded the received control information, the priority of the service transmission of the second terminal is compared with the priority of the service transmission of the first terminal. If the priority of the second terminal in the control information is equal to or higher than the priority of the service transmission of the first terminal, the time-frequency resource indicated in the control information among the resource candidates is determined as the occupied resource required for the service transmission of the second terminal. Among the resource candidates, resources other than the occupied resource required for the service transmission of the second terminal are the available resources. In other words, the first terminal can directly exclude the time-frequency resource indicated in the control information from resource candidates within the resource selection window, without considering the relationship between the RSRP value and the RSRP threshold.

[0033] Selectively determining the occupied resources required for the service transmission of the second terminal specifically includes, when a predetermined priority is set and the priority of the service transmission of the second terminal is lower than the predetermined priority, or when the predetermined priority is not set and the priority of the service transmission of the second terminal is lower than the priority of the service transmission of the first terminal, determining the occupied resources required for the service transmission of the second terminal based on the magnitude relationship between the signal reception power and a first threshold. After determining the resources other than the occupied resources required for the service transmission of the second terminal among the resource candidates as the available resources, the method further includes, when the available resources do not satisfy a predetermined condition, updating the first threshold according to a rule of sequentially increasing a predetermined value from the first threshold.

[0034] Selectively determining an occupied resource required for service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold specifically includes, when the signal reception power is equal to or greater than the first threshold, determining a time-frequency resource indicated in the control information from among the resource candidates as an occupied resource required for service transmission of the second terminal.

[0035] Optionally, after updating the first threshold, the method further includes updating the available resources based on a magnitude relationship between the updated first threshold and the signal received power until the available resources satisfy the predetermined condition.

[0036] Specifically, the predetermined priority is Pmin, which is set by higher layer signaling or is set and acquired in advance. If Pmin is set, after the first terminal has successfully decoded the received control information, the priority of the service transmission of the second terminal is compared with the priority of Pmin. If the priority of the second terminal in the control information is lower than the set priority Pmin, the LTE-V2X processing process is reused, and a relationship between the RSRP value and a first threshold (i.e., the RSRP threshold) is determined. If Pmin is not set, after the first terminal has successfully decoded the received control information, the priority of the service transmission of the second terminal is compared with the priority of the service transmission of the first terminal. If the priority of the second terminal in the control information is lower than the priority of the service transmission of the first terminal, the LTE-V2X processing process is reused, and a relationship between the RSRP value and a first threshold (i.e., the RSRP threshold) is determined. If the RSRP value is higher than the first threshold (i.e., the RSRP threshold), the resource is excluded from resource candidates in the resource selection window, and it is determined that the resource is not included in the available resources. If the available resources do not satisfy a predetermined condition by excluding the resource (i.e., the ratio of available resources is less than X% of the total number of resource candidates in the resource selection window, where X% is, for example, 20%, but not limited thereto), the RSRP threshold of the second terminal is increased by a predetermined value (YdBm) and the above process needs to be repeated until the ratio of available resources is equal to or greater than X% of the total number of resource candidates in the resource selection window. Then, the magnitude relationship between the updated first threshold and the signal reception power is determined, and if the RSRP value is greater than the updated RSRP threshold, the resource is excluded from the resource candidates in the resource selection window. If the RSRP value is equal to or less than the updated RSRP threshold, the resource is not excluded from the resource candidates in the resource selection window, i.e., the resource is included in the available resources. Then, a target resource required for service transmission is selected from the available resources based on the priority of service transmission of the first terminal.

[0037] A detailed description will be given below with specific examples. Figure 5 shows a case where Pmin is not set. UE3 receives TB at time n and needs to select service transmission resources. UE3 senses UE1 and UE2 in its sensing window. The reserved resources of UE1 and UE2 are as shown in Figure 5. The priority relationship is UE1>UE3>UE2. The resource selection window of UE3 is from (n+T1) to (n+T2), and the number of transmissions is 4.

[0038] UE3 resource exclusion process: UE3 obtains the time-frequency resource reservation information of the second / third / fourth transmission by UE1 by decoding the control information of UE1. Because the priority of UE1 is higher than that of UE3, UE3 directly excludes the reservation information of UE1 from the resource candidates in the resource selection window, and does not need to consider the relationship between the RSRP value and the RSRP threshold. UE3 obtains the time-frequency resource information reserved in the second / third / fourth transmission by UE2 by decoding the control information of UE2. Because the priority of UE2 is lower than that of UE3, UE3 judges the relationship between the RSRP of the first transmission of UE2 and the RSRP threshold. If the RSRP of the first transmission of UE2 is equal to or higher than the RSRP threshold, it is necessary to exclude the resources reserved by UE2 from the resource candidates. Otherwise, it is not necessary to exclude them.

[0039] As shown in Figure 5, in the first resource exclusion process, the RSRP of UE2's initial transmission exceeds the RSRP threshold, and the resources reserved by UE2 need to be excluded from the resource candidates in the resource selection window. After the first resource exclusion process, the proportion of available resources for UE3 is less than 20%, and the RSRP threshold of low priority UE2 needs to be increased by YdBm. After the adjustment by updating the RSRP threshold, the RSRP value is less than the RSRP threshold, so there is no need to exclude the resources reserved by UE2, and the proportion of available resources increases to meet the requirement of 20%.

[0040] Selectively determining the occupied resources required for the service transmission of the second terminal specifically includes determining the occupied resources required for the service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold. After determining the resources other than the occupied resources required for the service transmission of the second terminal among the resource candidates as the available resources, the method further includes updating the first threshold according to a rule of sequentially increasing a predetermined value from the first threshold on the premise that the first threshold is smaller than a second threshold when the available resources do not satisfy a predetermined condition.

[0041] Selectively determining an occupied resource required for service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold specifically includes, when the signal reception power is equal to or greater than the first threshold, determining a time-frequency resource indicated in the control information from among the resource candidates as an occupied resource required for service transmission of the second terminal.

[0042] Optionally, after updating the first threshold, the method further includes updating the available resources based on a magnitude relationship between the updated first threshold and the signal received power until the available resources satisfy the predetermined condition.

[0043] Specifically, the respective priorities of transmission and reception by the first terminal and the adjustable RSRP threshold corresponding to each priority terminal are set by upper layer signaling or are previously set and obtained. After the first terminal successfully decodes the received control information, based on the priority (for example: N) of the service transmission of the second terminal in the control information and the priority (for example: M) of the service transmission (transmission target service) of the first terminal, the first terminal determines the initial RSRP threshold and the adjustable RSRP upper limit value (RSRPmax) for sensing and judging the resource occupancy situation based on the transmission and reception priorities N and M, and maps them to the resource candidates in the resource selection window, and the resources whose RSRP exceeds the RSRP threshold need to be excluded. If the ratio of available resources is less than X% of the total number of resource candidates in the resource selection window, the following process is required. The RSRP threshold that does not reach the set RSRPmax is increased by YdBm, and the above process is repeated until the ratio of available resources is equal to or greater than X% of the total number of resource candidates in the resource selection window, and then judges the magnitude relationship between the updated RSRP threshold and the signal reception power. If the RSRP value is greater than the updated RSRP threshold, the resource is excluded from the resource candidates in the resource selection window. If the RSRP value is equal to or less than the updated RSRP threshold, the resource is not excluded from the resource candidates in the resource selection window. That is, the resource is included in the available resources. Then, a target resource required for service transmission is selected from the available resources according to the priority of the service transmission of the first terminal. If the configured RSRPmax is reached in the updating process, the RSRP threshold is not updated.

[0044] A detailed description will be given below with a specific embodiment. As shown in Fig. 6, UE3 receives a TB at time n and needs to select a service transmission resource. UE3 detects UE1 and UE2 in the detection window, and the reserved resources of UE1 and UE2 are as shown in Fig. 6. The priority relationship is UE1>UE3>UE2. The resource selection window of UE3 is from (n+T1) to (n+T2), and the number of transmissions is 4.

[0045] UE3 resource exclusion process: According to the priority relationship of UE1, UE2 and UE3, the adjustable maximum value RSRPmax of the RSRP threshold of UE1 and UE2 (RSRPmax of UE1 and UE2 may be the same or different) is set by upper layer signaling or obtained in advance. Based on the initial RSRP threshold, resource exclusion is performed, that is, all reserved resources of UE1 and UE2 are excluded. At that time, the ratio of available resources is less than 20% of the total number of resource candidates in the resource selection window. If the RSRP threshold of UE1 is increased by YdBm, it will exceed RSRPmax, so the RSRP threshold of UE1 is not adjusted and the reserved resources of UE1 are excluded from the resource selection window. If the RSRP threshold of UE2 is increased by YdBm, it will not exceed RSRPmax and the current ratio of available resources is less than 20%, so the RSRP threshold of UE2 is increased by YdBm. After adjusting the RSRP threshold of UE2, the RSRP value is smaller than the adjusted RSRP threshold, so there is no need to exclude the reserved resources of UE2 from the resource candidates in the resource selection window, and the proportion of available resources increases to meet the requirement of 20%.

[0046] Optionally, determining the occupied resources required for the service transmission of the second terminal includes determining the occupied resources required for the service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold, and after determining resources other than the occupied resources required for the service transmission of the second terminal from among the resource candidates as the available resources, if the available resources do not satisfy a predetermined condition, the method further includes updating the first threshold according to a rule of sequentially increasing a predetermined value from the first threshold, provided that the number of updates of the first threshold is less than a predetermined number.

[0047] Selectively determining an occupied resource required for service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold specifically includes, when the signal reception power is equal to or greater than the first threshold, determining a time-frequency resource indicated in the control information from among the resource candidates as an occupied resource required for service transmission of the second terminal.

[0048] Optionally, after updating the first threshold, the method further includes updating the available resources based on a magnitude relationship between the updated first threshold and the signal received power until the available resources satisfy the predetermined condition.

[0049] Specifically, the respective priorities of transmission and reception by the first terminal and the adjustable number of times of the RSRP threshold corresponding to each priority terminal are set by upper layer signaling or are obtained by being set in advance. After the first terminal successfully decodes the received control information, based on the priority (for example: N) of the service transmission of the second terminal in the control information and the priority (for example, M) of the service transmission (transmission target service) of the first terminal, the first terminal determines the initial RSRP threshold and the predetermined number of times of the adjustable RSRP threshold for sensing and judging the resource occupancy situation (i.e., the upper limit of the number of adjustments Tmax) based on the priorities N and M of transmission and reception, and maps them to the resource candidates in the resource selection window, and the resources whose RSRP exceeds the RSRP threshold need to be excluded. If the proportion of available resources is less than X% of the total number of resource candidates in the resource selection window, the following process is required. The RSRP threshold that does not reach the set Tmax is increased by Y dBm, and the above process is repeated until the ratio of available resources is equal to or greater than X% of the total number of resource candidates in the resource selection window, and then the relationship between the updated RSRP threshold and the signal reception power is determined. If the RSRP value is greater than the updated RSRP threshold, the resource is excluded from the resource candidates in the resource selection window. If the RSRP value is equal to or less than the updated RSRP threshold, the resource is not excluded from the resource candidates in the resource selection window. That is, the resource is included in the available resources. Then, a target resource required for service transmission is selected from the available resources based on the priority of the service transmission of the first terminal. If the set Tmax is reached in the updating process, the RSRP threshold is not updated.

[0050] A detailed explanation will be given below using specific examples.

[0051] As shown in Figure 7, UE3 receives TB at time n and needs to select service transmission resources. UE3 detects UE1 and UE2 in the detection window, and the reserved resources of UE1 and UE2 are as shown in Figure 7. The priority relationship is UE1>UE3>UE2. The resource selection window of UE3 is from (n+T1) to (n+T2), and the number of transmissions is 4.

[0052] UE3 resource exclusion process: According to the priority relationship of UE1, UE2 and UE3, the upper limit Tmax of the number of times that the RSRP threshold of UE1 and UE2 can be adjusted (UE1 is set to once, UE2 is set to twice) is set by upper layer signaling or obtained in advance. Based on the initial RSRP threshold, resource exclusion is performed, that is, all the reserved resources of UE1 and UE2 are excluded. At that time, the ratio of available resources is less than 20% of the total number of resource candidates in the resource selection window. When the RSRP thresholds of UE1 and UE2 are adjusted by YdBm, the RSRP values ​​of UE1 and UE2 are both less than the updated RSRP threshold, all the reserved resources of UE1 and UE2 are still excluded, and the ratio of available resources is still less than 20%. Since the maximum number of times of RSRP threshold adjustment of UE1 is reached, only the RSRP threshold of UE2 is adjusted. The RSRP of UE2 after adjustment is less than the updated RSRP threshold twice, so there is no need to exclude the reserved resources of UE2, and the ratio of available resources meets the condition of 20%.

[0053] Selectively determining the occupied resource required for the service transmission of the second terminal specifically includes determining the occupied resource required for the service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold. After determining the resource candidate other than the occupied resource required for the service transmission of the second terminal as the available resource, if the available resource does not satisfy a predetermined condition, the method further includes updating the first threshold according to a rule of sequentially increasing the boost value from the first threshold based on a correspondence relationship between the priority of the service transmission of the second terminal and a boost value.

[0054] Selectively determining an occupied resource required for service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold specifically includes, when the signal reception power is equal to or greater than the first threshold, determining a time-frequency resource indicated in the control information from among the resource candidates as an occupied resource required for service transmission of the second terminal.

[0055] Optionally, after updating the first threshold, the method further includes updating the available resources based on a magnitude relationship between the updated first threshold and the signal received power until the available resources satisfy the predetermined condition.

[0056] Specifically, the respective priorities of transmission and reception by the first terminal and the magnitude of each time adjustment of the adjustable RSRP threshold corresponding to each priority terminal are set by upper layer signaling or are obtained by being set in advance. After the first terminal successfully decodes the received control information, based on the priority (for example: N) of the service transmission of the second terminal in the control information and the priority (for example, M) of the service transmission (transmission target service) of the first terminal, the first terminal determines the initial RSRP threshold and the magnitude of the adjustable RSRP for sensing and judging the resource occupancy situation based on the priorities N and M of transmission and reception, and maps them to resource candidates in the resource selection window, and resources whose RSRP exceeds the RSRP threshold need to be excluded. If the proportion of available resources is less than X% of the total number of resource candidates in the resource selection window, the RSRP threshold is raised based on the magnitude (i.e., the raising value) of the adjustable RSRP threshold for each time of different priorities until the proportion of available resources is equal to or greater than X% of the total number of resource candidates in the resource selection window. Then, the updated RSRP threshold and the signal reception power are compared to determine whether they are larger or smaller, and if the RSRP value is larger than the updated RSRP threshold, the resource is excluded from the resource candidates in the resource selection window. If the RSRP value is equal to or smaller than the updated RSRP threshold, the resource is not excluded from the resource candidates in the resource selection window. That is, the resource is included in the available resources. Then, a target resource required for service transmission is selected from the available resources based on the priority of service transmission of the first terminal.

[0057] Optionally, if the priority of the service transmission of the first terminal is equal to or higher than the priority of the service transmission of the second terminal, after determining the occupied resources required for the service transmission of the second terminal, the method further includes determining, as the available resources, among the resource candidates, resources in an idle state and the occupied resources required for the service transmission of the second terminal, based on the occupied resources required for the service transmission of the second terminal.

[0058] Specifically, the high priority UE (i.e., the first terminal) directly preempts resources, regardless of whether the resources are free available resources or already occupied by the low priority UE (i.e., the second terminal). According to the size of the occupied resources required for the transmission target service, the first terminal selects both the idle resources and the occupied resources of the low priority UE as available resources among the resource candidates, regardless of whether the resources are already occupied, and then selects the target resources required for the service transmission from the available resources based on the priority of the service transmission of the first terminal.

[0059] A detailed description will be given below using a specific embodiment. Figure 8 shows the resource selection window of the first terminal (UE1). Assume that UE1 needs four transmissions, occupies one subchannel for each transmission, and cannot transmit twice in the same time slot. The third and fourth columns are unoccupied resources, i.e., idling resources, the first, second, fifth, and sixth columns are resources that are determined to be occupied by a low priority UE based on the received control information, and the seventh and eighth columns are resources that are determined to be occupied by other high priority UEs based on the received control information. The resource selection method of UE1 is processed directly based on the priority in the received control information. That is, all idling resources (the third and fourth columns) and resources occupied by low priority UEs (the first, second, fifth, and sixth columns) in the resource selection window are treated as available resources as they are, and the update of the RSRP threshold for the resources occupied by low priority UEs is not considered. Then, a target resource required for service transmission is selected from the available resources based on the priority of the service transmission of the first terminal.

[0060] Optionally, if the priority of the service transmission of the first terminal is equal to or higher than the priority of the service transmission of the second terminal, after determining the occupied resources required for the service transmission of the second terminal, the method further includes determining, as the available resource, a resource in an idle state among the resource candidates based on the occupied resources required for the service transmission of the second terminal.

[0061] Specifically, as the preemption of a high priority UE (i.e., the first terminal) to a low priority UE (i.e., the second terminal) based on the RSRP threshold, specifically, the high priority UE performs the following process on the resources in the resource selection window based on the size of the occupied resources required for the transmission target service. Based on the decoded control information, the resources occupied by the high priority and low priority UEs are completely excluded, the idle resources are set as available resources, and it is then determined whether the idle resources meet the transmission conditions (i.e., whether the ratio of the available resources is equal to or greater than X% of the total number of resource candidates in the resource selection window). If the idle resources do not meet the transmission conditions, it is necessary to perform resource exclusion based on the RSRP for the resources occupied by the low priority UE (i.e., to compare the RSRP of the low priority UE with the RSRP threshold), and to determine whether the available resources meet the transmission conditions. If the transmission conditions are not met, the RSRP threshold is increased by Y dBm, and the RSRP threshold is continued to be updated until the available resources meet the transmission conditions. Then, based on the priority of the service transmission of the first terminal, the target resources required for the service transmission are selected from the available resources.

[0062] A detailed description will be given below using specific examples. FIG. 8 shows a resource selection window of a first terminal (UE1). Assume that UE1 requires four transmissions, occupies one subchannel for each transmission, and two transmissions cannot be performed in the same time slot. The third and fourth columns are unoccupied resources, i.e., idling resources, the first, second, fifth, and sixth columns are resources that are determined to be occupied by a low priority UE based on the received control information, and the seventh and eighth columns are resources that are determined to be occupied by another high priority UE based on the received control information. The resource selection method of UE1 excludes resources including those occupied by low and high priority UEs based on the successfully decoded control information, and the available resources are only idling resources, which do not satisfy the transmission condition. It is necessary to exclude resources occupied by low priority UEs by updating the RSRP threshold. As shown in FIG. 9, the newly added second and fifth columns are available resources. That is, the resources in the second to fifth columns satisfy the transmission condition as available resources. Then, based on the priority of the service transmission of the first terminal, a target resource required for the service transmission is selected from the available resources.

[0063] In the above embodiment of the present disclosure, different RSRP processing methods are set for high priority UEs and low priority UEs, so that high priority UEs can preempt resources and low priority UEs can avoid occupying high priority resources during resource selection, thereby ensuring the transmission reliability of high priority UEs. Different resource selection mechanisms are set, and random selection and preemption of UEs with high latency requirements ensures that the transmission delay meets the requirements. UEs with low latency requirements can preferentially select idle resources, and preempt resources when the transmission conditions are not met, ensuring the transmission reliability.

[0064] As shown in Fig. 10, an embodiment of the present disclosure further provides a terminal including a transceiver, a memory, a processor, and a program stored in the memory and executable by the processor. The processor acquires basic information transmitted from a second terminal, the basic information including a priority of service transmission of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information, determines available resources available for service transmission among resource candidates based on the priority of service transmission of the second terminal and the signal reception power, and selects a target resource required for service transmission from the available resources based on the priority of service transmission of the first terminal.

[0065] Here, in FIG. 10, the bus architecture includes any number of interconnecting buses and bridges, specifically connecting one or more processors, such as processor 1000, and various types of memory circuits, such as memory 1020. The bus architecture may also connect various types of other circuits, such as peripheral equipment, regulators, power management circuits, etc., all of which are known in the art and will not be described further herein. The bus interface provides an interface. The transceiver 1010 may be multiple components, i.e., includes a transmitter and a receiver, and is provided as a unit that communicates with various types of other devices over a transmission medium. Depending on the user terminal, the user interface 1030 may be an interface for internal or external connected devices. The connected devices include, but are not limited to, a keypad, a display, a speaker, a microphone, a joystick, etc.

[0066] The processor 1000 manages the bus architecture and normal operations. The memory 1020 may store data used during operation by the processor 1000.

[0067] Optionally, when determining available resources that can be used for service transmission from among the resource candidates, the processor 1000 specifically determines occupied resources required for the service transmission of the second terminal based on the priority of the service transmission of the second terminal and / or the signal reception power, and determines resources other than the occupied resources required for the service transmission of the second terminal from among the resource candidates as the available resources based on the occupied resources required for the service transmission of the second terminal.

[0068] Optionally, when determining the dedicated resources required for the service transmission of the second terminal, the processor 1000 specifically determines, among the resource candidates, a time-frequency resource indicated in the control information as the dedicated resource required for the service transmission of the second terminal when a predetermined priority is set and the priority of the service transmission of the second terminal is equal to or higher than the predetermined priority, or when the predetermined priority is not set and the priority of the service transmission of the second terminal is equal to or higher than the priority of the service transmission of the first terminal.

[0069] Optionally, when determining the dedicated resources required for the service transmission of the second terminal, the processor 1000 specifically determines the dedicated resources required for the service transmission of the second terminal based on the magnitude relationship between the signal reception power and a first threshold value when a predetermined priority is set and the priority of the service transmission of the second terminal is lower than the predetermined priority, or when the predetermined priority is not set and the priority of the service transmission of the second terminal is lower than the priority of the service transmission of the first terminal. After determining the resources other than the dedicated resources required for the service transmission of the second terminal from among the resource candidates as the available resources, the processor 1000 further updates the first threshold value according to a rule of sequentially increasing a predetermined value from the first threshold value if the available resources do not satisfy a predetermined condition.

[0070] Optionally, the processor 1000 determines the dedicated resources required for the service transmission of the second terminal based on the magnitude relationship between the signal reception power and a first threshold when determining the dedicated resources required for the service transmission of the second terminal, specifically, based on the magnitude relationship between the signal reception power and a first threshold. After determining the resources other than the dedicated resources required for the service transmission of the second terminal as the available resources among the resource candidates, the processor 1000 further updates the first threshold according to a rule of sequentially increasing a predetermined value from the first threshold on the premise that the first threshold is smaller than the second threshold when the available resources do not satisfy a predetermined condition.

[0071] Optionally, when determining the occupied resource required for the service transmission of the second terminal, the processor 1000 specifically determines the occupied resource required for the service transmission of the second terminal based on the magnitude relationship between the signal reception power and a first threshold. After determining the resource other than the occupied resource required for the service transmission of the second terminal from among the resource candidates as the available resource, if the available resource does not satisfy a predetermined condition, the processor 1000 updates the first threshold according to a rule of sequentially increasing a predetermined value from the first threshold on the premise that the update count of the first threshold is smaller than a predetermined number.

[0072] Optionally, the processor 1000 determines the dedicated resources required for the service transmission of the second terminal based on the magnitude relationship between the signal reception power and a first threshold when determining the dedicated resources required for the service transmission of the second terminal, specifically, based on the magnitude relationship between the signal reception power and a first threshold. After determining the resources other than the dedicated resources required for the service transmission of the second terminal as the available resources among the resource candidates, the processor 1000 updates the first threshold according to a rule of sequentially increasing the increase value from the first threshold based on the correspondence relationship between the priority of the service transmission of the second terminal and an increase value.

[0073] Optionally, when determining the occupied resource required for the service transmission of the second terminal based on the magnitude relationship between the signal reception power and a first threshold, specifically, when the signal reception power is equal to or greater than the first threshold, the processor 1000 determines, from among the resource candidates, a time-frequency resource indicated in the control information as the occupied resource required for the service transmission of the second terminal.

[0074] Optionally, after updating the first threshold, the processor 1000 further updates the available resources based on the magnitude relationship between the updated first threshold and the signal received power until the available resources satisfy the specified condition.

[0075] Optionally, when the priority of the service transmission of the first terminal is equal to or higher than the priority of the service transmission of the second terminal, the processor 1000 determines the occupied resources required for the service transmission of the second terminal, and then, based on the occupied resources required for the service transmission of the second terminal, determines, as the available resources, among the resource candidates, the resources in an idle state and the occupied resources required for the service transmission of the second terminal.

[0076] Optionally, when the priority of the service transmission of the first terminal is equal to or higher than the priority of the service transmission of the second terminal, the processor 1000 determines the occupied resources required for the service transmission of the second terminal, and then further determines, based on the occupied resources required for the service transmission of the second terminal, a resource in an idle state among the resource candidates as the available resource.

[0077] When executed by the processor 1000, this program can realize all the implementation methods in the embodiments of the resource selection method applied to the first terminal described above and achieve the same technical effects, so in order to avoid duplication, they will not be described repeatedly here.

[0078] As shown in Fig. 11, the embodiment of the present disclosure further provides a terminal, which is a first terminal, and includes: a first acquisition module 111 for acquiring basic information transmitted from a second terminal, the basic information including a priority of service transmission of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information, a first determination module 112 for determining an available resource available for service transmission among resource candidates based on the priority of service transmission of the second terminal and the signal reception power, and a first processing module 113 for selecting a target resource required for service transmission from the available resources based on the priority of service transmission of the first terminal.

[0079] Optionally, the first determination module 112 includes a first determination unit for determining occupied resources required for service transmission of the second terminal based on the priority of service transmission of the second terminal and / or the signal reception power, and a second determination unit for determining resources other than the occupied resources required for service transmission of the second terminal among the resource candidates as the available resources based on the occupied resources required for service transmission of the second terminal.

[0080] Optionally, the first determination unit includes a first determination subunit for determining, when a predetermined priority is set and the priority of the service transmission of the second terminal is equal to or higher than the predetermined priority, or when the predetermined priority is not set and the priority of the service transmission of the second terminal is equal to or higher than the priority of the service transmission of the first terminal, a time-frequency resource indicated in the control information among the resource candidates as an occupied resource required for the service transmission of the second terminal.

[0081] Optionally, the first determination unit includes a second determination subunit for determining an occupied resource required for the service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold value when a predetermined priority is set and the priority of the service transmission of the second terminal is lower than the predetermined priority, or when the predetermined priority is not set and the priority of the service transmission of the second terminal is lower than the priority of the service transmission of the first terminal. The terminal further includes a second processing module for updating the first threshold value according to a rule of sequentially increasing a predetermined value from the first threshold value when the available resource does not satisfy a predetermined condition.

[0082] Optionally, the first determining unit includes a third determining subunit for determining an occupied resource required for service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold. The terminal further includes a third processing module for updating the first threshold according to a rule of sequentially increasing a predetermined value from the first threshold, on the condition that the first threshold is smaller than a second threshold, when the available resource does not satisfy a predetermined condition.

[0083] Optionally, the first determining unit includes a fourth determining subunit for determining an occupied resource required for service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold. The terminal further includes a fourth processing module for updating the first threshold according to a rule of sequentially increasing a predetermined value from the first threshold, on the condition that the update count of the first threshold is smaller than a predetermined count, when the available resource does not satisfy a predetermined condition.

[0084] Optionally, the first determining unit includes a fifth determining subunit for determining an occupied resource required for the service transmission of the second terminal based on a magnitude relationship between the signal reception power and a first threshold. The terminal further includes a fifth processing module for updating the first threshold according to a rule of sequentially increasing the boost value from the first threshold based on a corresponding relationship between the priority of the service transmission of the second terminal and a boost value when the available resource does not satisfy a predetermined condition.

[0085] Optionally, the second determination subunit, the third determination subunit, the fourth determination subunit, and the fifth determination subunit determine, when the signal reception power is greater than or equal to the first threshold, a time-frequency resource indicated in the control information among the resource candidates as an occupied resource required for service transmission of the second terminal.

[0086] Optionally, the terminal further includes an update module for updating the available resources based on a magnitude relationship between an updated first threshold and the signal reception power until the available resources satisfy the predetermined condition.

[0087] Optionally, when the priority of the service transmission of the first terminal is equal to or higher than the priority of the service transmission of the second terminal, the terminal further includes a second determination module for determining, based on the occupied resources required for the service transmission of the second terminal, resources in an idle state and the occupied resources required for the service transmission of the second terminal among the resource candidates as the available resources.

[0088] Optionally, when the priority of the service transmission of the first terminal is equal to or higher than the priority of the service transmission of the second terminal, the terminal further includes a third determination module for determining, as the available resource, a resource in an idle state among the resource candidates based on an occupied resource required for the service transmission of the second terminal.

[0089] The terminal according to the embodiments of the present disclosure can realize all the implementation methods in the embodiments of the resource selection method applied to the first terminal described above and achieve the same technical effects, so in order to avoid duplication, they will not be described here repeatedly.

[0090] In some embodiments of the present disclosure, a computer-readable storage medium having a computer program stored thereon is further provided, which, when executed by a processor, realizes the steps of: acquiring basic information transmitted from a second terminal, the basic information including a priority of service transmission of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information; determining available resources that can be used for service transmission among resource candidates based on the priority of service transmission of the second terminal and the signal reception power; and selecting a target resource required for service transmission from the available resources based on the priority of service transmission of the first terminal.

[0091] When the program is executed by a processor, it can realize all the implementation methods in the embodiments of the resource selection method applied to the first terminal described above and achieve the same technical effects, so in order to avoid duplication, it will not be described repeatedly here.

[0092] In each embodiment of the present disclosure, the magnitude of the numbers of each of the above processes does not mean the order of execution, and the order of execution of each process is determined by its function and inherent logic, and it should be understood that this does not constitute any limitation on the implementation process of the embodiments of the present disclosure.

[0093] The above description is the optional embodiment of the present disclosure. Those skilled in the art can make various improvements and modifications without departing from the principles described in the present disclosure. These improvements and modifications should also be considered as part of the protection scope of the present disclosure.

Claims

1. A resource selection method applied to a first terminal, comprising: Acquiring basic information transmitted from a second terminal, the basic information including a priority of a service transmission of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information; determining an available resource that is available for service transmission among resource candidates based on the priority of service transmission of the second terminal and the signal reception power; Selecting a target resource required for service transmission from the available resources according to a priority of the service transmission of the first terminal; Determining available resources available for service transmission among the resource candidates includes determining occupied resources required for service transmission of the second terminal based on a priority of the service transmission of the second terminal and / or the signal reception power; determining, as the available resource, resources other than the dedicated resources required for the service transmission of the second terminal, among the resource candidates, based on the dedicated resources required for the service transmission of the second terminal; Determining the occupied resources required for the service transmission of the second terminal includes determining, among the resource candidates, a time-frequency resource indicated by the control information as an occupied resource required for the service transmission of the second terminal, when a predetermined priority is set and the priority of the service transmission of the second terminal is equal to or higher than the predetermined priority, so that the first terminal does not need to consider a relationship between an RSRP value and an RSRP threshold, and can directly exclude the time-frequency resource indicated by the control information from resource candidates in a resource selection window. Resource selection method.

2. When the priority of the service transmission of the first terminal is equal to or higher than the priority of the service transmission of the second terminal, after determining the occupied resources required for the service transmission of the second terminal, determining, as the available resources, the resources in an idle state and the occupied resources required for the service transmission of the second terminal among the resource candidates based on the occupied resources required for the service transmission of the second terminal; or, 2. The resource selection method of claim 1, further comprising: when a priority of the service transmission of the first terminal is equal to or higher than a priority of the service transmission of the second terminal, determining an occupied resource required for the service transmission of the second terminal, and then determining an idle resource among the resource candidates as the available resource based on the occupied resource required for the service transmission of the second terminal.

3. A terminal, the terminal being a first terminal, comprising a transceiver, a memory, a processor, and a program stored in the memory and executable by the processor; The processor acquires basic information transmitted from a second terminal, the basic information including a priority of a service transmission of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information; determining an available resource that can be used for service transmission among the resource candidates based on the priority of the service transmission of the second terminal and the signal reception power; Selecting a target resource required for service transmission from the available resources according to the priority of the service transmission of the first terminal; When determining available resources available for service transmission among the resource candidates, the processor specifically determines an occupied resource required for the service transmission of the second terminal based on a priority of the service transmission of the second terminal and / or the signal reception power; determining, as the available resource, resources other than the dedicated resources required for the service transmission of the second terminal, among the resource candidates, based on the dedicated resources required for the service transmission of the second terminal; Specifically, when determining the occupied resources required for the service transmission of the second terminal, if a predetermined priority is set and the priority of the service transmission of the second terminal is equal to or higher than the predetermined priority, the first terminal does not need to consider the relationship between the RSRP value and the RSRP threshold, and determines the time-frequency resource indicated in the control information as the occupied resource required for the service transmission of the second terminal among the resource candidates, so that the time-frequency resource indicated in the control information can be directly excluded from the resource candidates in a resource selection window. Terminal.

4. When the priority of the service transmission of the first terminal is equal to or higher than the priority of the service transmission of the second terminal, the processor determines the occupied resources required for the service transmission of the second terminal, and then determines, based on the occupied resources required for the service transmission of the second terminal, the idle resources and the occupied resources required for the service transmission of the second terminal among the resource candidates as the available resources; or, 4. The terminal according to claim 3, wherein when the priority of the service transmission of the first terminal is equal to or higher than the priority of the service transmission of the second terminal, the processor determines the occupied resources required for the service transmission of the second terminal, and then further determines, based on the occupied resources required for the service transmission of the second terminal, a resource that is in an idle state among the resource candidates as the available resource.

5. A terminal, the terminal being a first terminal; A first acquiring module for acquiring basic information sent from a second terminal, the basic information including a priority of a service transmission of the second terminal in control information and a signal reception power corresponding to the service transmission of the second terminal in service data information; a first determination module for determining an available resource available for service transmission among resource candidates according to the priority of service transmission of the second terminal and the signal reception power; a first processing module for selecting a target resource required for service transmission from the available resources based on a priority of the service transmission of the first terminal; The first processing module specifically determines an occupied resource required for the service transmission of the second terminal according to a priority of the service transmission of the second terminal and / or the signal reception power; determining, as the available resource, resources other than the dedicated resources required for the service transmission of the second terminal, among the resource candidates, based on the dedicated resources required for the service transmission of the second terminal; Specifically, when a predetermined priority is set and the priority of the service transmission of the second terminal is equal to or higher than the predetermined priority, the first processing module determines the time-frequency resource indicated in the control information among the resource candidates as the occupied resource required for the service transmission of the second terminal, so that the first terminal does not need to consider the relationship between the RSRP value and the RSRP threshold and can directly exclude the time-frequency resource indicated in the control information from the resource candidates in a resource selection window. Terminal.

6. A computer-readable storage medium having stored thereon a computer program which, when executed by a processor, causes the steps of the resource selection method according to claim 1 or 2 to be implemented.

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