Method and device for obtaining and positioning eigenvalue of mobile terminal based on NR system

Abstract

This application relates to the field of mobile communication technologies, and discloses a method and apparatus for obtaining and positioning mobile terminal eigenvalue based on the NR system, including the following steps: S1. Start the base station and configure the coverage range and parameters of the NR network; S2. Receive the RRC connection request of the mobile terminal and establish a communication link; S3. Send an identity request signaling and receive a response signaling containing SUCI; S4. Decode the SUCI into IMSI and determine whether it is the target user; S5. Perform periodic pre-scheduling on the target user to maintain the stability of the link; S6. Locate the target terminal through signal strength and direction information. Through the periodic pre-scheduling in a specific time domain and frequency domain, signaling communication without data interaction is realized, thereby reducing the dependence on traffic during the communication process, and further avoiding the problem of data traffic consumption, and solving the deficiency of high communication cost in the traditional method.

Description

Technical Field

[0001] The present invention relates to the technical field of mobile communications, and particularly to a method and device for obtaining and positioning mobile terminal eigenvalue based on the NR system. Background Art

[0002] With the rapid development of 5G communication technology, NR (New Radio), as one of the core technologies of 5G networks, has brought higher spectral efficiency, lower latency, and wider network coverage capabilities to the field of mobile communications. Mobile terminal positioning and IMSI (International Mobile Subscriber Identity) acquisition technologies based on the NR system play important roles in multiple fields. For example, in network management, user authentication, and emergency response scenarios, the rapid acquisition of IMSI is the key to realizing user management and resource allocation. At the same time, precise positioning technology provides effective support for scenarios such as maritime rescue and forest protection. In the prior art, IMSI is mostly obtained through signaling interaction or data communication, and target user positioning is completed by means of path loss models or multi-base station cooperation. These methods can meet the basic requirements in most conventional application scenarios.

[0003] However, with the diversification and complexity of application scenarios, the prior art still has certain limitations in some specific scenarios. For example, traditional IMSI acquisition methods usually rely on data communication, which is prone to high traffic consumption and may pose potential risks to user privacy protection. In complex dynamic environments, such as post-disaster search and rescue or high-mobility target positioning, traditional positioning methods are often limited by signal interference and unstable links, making it difficult to achieve precise positioning. In addition, the prior art requires a long debugging cycle during deployment and still shows insufficient response capabilities for emergencies or urgent tasks. These problems limit the application effects of the prior art in terms of rapid deployment, high-precision positioning, and resource optimization. Therefore, it is urgent to propose new technical solutions to solve these problems. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention provides a method and device for obtaining and positioning mobile terminal eigenvalue based on the NR system, which solves the problems of high traffic consumption, insufficient privacy protection in IMSI acquisition, low positioning accuracy, and slow deployment response in the prior art.

[0005] To achieve the above objectives, the present invention is realized through the following technical solutions: A method for obtaining and positioning mobile terminal eigenvalue based on the NR system includes the following steps:

[0006] S1. Start the base station and configure the coverage range and specific parameters of the NR network, including the TDD time slot ratio in the time domain and the resource block position in the frequency domain;

[0007] S2. Receive the RRC connection request sent by the mobile terminal within the coverage of the base station to complete the establishment of the communication link;

[0008] S3. The base station sends an identity request signaling to the mobile terminal and receives the identity response signaling returned by the mobile terminal, which contains the subscriber privacy identifier of the mobile terminal, i.e., SUCI;

[0009] S4. The base station decodes the SUCI into the international mobile subscriber identity, i.e., IMSI, and determines whether the IMSI is the target user;

[0010] S5. For the target user, the base station performs periodic pre-scheduling on the target terminal in the fixed time domain and frequency domain to maintain the stable connection of the link and avoid interfering with non-target users;

[0011] S6. The base station gradually determines the position of the target terminal through the signal strength feedback by the target terminal, combined with the direction information of the directional antenna and the signal strength change information.

[0012] Preferably, the pre-scheduling in step S5 includes:

[0013] In the time domain, the base station schedules the target terminal at a fixed sub-frame position;

[0014] In the frequency domain, the base station allocates a specific resource block range for the target terminal, and the signaling scheduling of non-target terminals avoids this frequency domain;

[0015] The period of the pre-scheduling is 10 ms. The base station maintains signaling interaction with the target terminal within each period without generating data traffic.

[0016] Preferably, the target terminal positioning in step S6 includes the following:

[0017] The base station receives the signal strength periodically reported by the target terminal;

[0018] Determine the maximum direction of the target terminal signal strength through multi-angle scanning of the directional antenna;

[0019] Determine the distance between the base station and the target terminal according to the signal strength;

[0020] Combine the direction and distance information to gradually approach the position of the target terminal.

[0021] Preferably, the signal strength of the target terminal received by the base station has an inverse relationship with the distance and is processed by smoothing the feedback signal.

[0022] Preferably, this method is applicable to specific scenarios under the NR network, including maritime rescue, forest and grassland protection, criminal investigation, and post-disaster positioning application scenarios.

[0023] Preferably, the directional antenna of the base station has the ability to scan at multiple angles and supports target positioning tasks in a dynamic environment in combination with the movement direction of the base station.

[0024] The mobile terminal for grabbing IMSI and positioning device based on the NR system includes:

[0025] Base station transceiver module: used to receive the RRC connection request of the mobile terminal and complete the establishment of the communication link;

[0026] SUCI acquisition module: used to receive the subscriber privacy identifier returned by the mobile terminal;

[0027] IMSI conversion module: used to decode the SUCI into the international mobile subscriber identification number;

[0028] Link maintenance module: used to perform periodic pre-scheduling on the target terminal within a specific time domain and frequency domain to maintain signaling interaction and avoid interfering with non-target terminals;

[0029] Positioning module: used to gradually locate the target terminal by combining the signal strength feedback from the target terminal with the information of the directional antenna.

[0030] Preferably, the link maintenance module includes:

[0031] A time domain scheduling unit for allocating a fixed subframe position to the target terminal;

[0032] A frequency domain scheduling unit for allocating a fixed resource block range to the target terminal and ensuring that the frequency domain resource allocation of non-target terminals is separated from that of the target terminal;

[0033] A pre-scheduling unit for periodically scheduling the signaling interaction of the target terminal every 10 ms to ensure a continuous link connection and no data traffic consumption.

[0034] Preferably, the positioning module includes:

[0035] Signal receiving unit: used to receive the signal strength feedback from the target terminal;

[0036] Direction determination unit: used to determine the direction where the target terminal is located through the direction change information of the signal strength;

[0037] Distance calculation unit: used to estimate the distance between the target terminal and the base station according to the relationship between the signal strength and the distance;

[0038] Positioning analysis unit: used to gradually determine the position of the target terminal by combining the direction and distance information.

[0039] Preferably, the signal receiving unit of the positioning module is further configured to perform weighted smoothing processing on the signal strength feedback value within a fixed time window to reduce the influence of signal fluctuations on the positioning accuracy.

[0040] The present invention provides a method and apparatus for obtaining mobile terminal characteristic values and positioning based on the NR system. It has the following beneficial effects:

[0041] 1. Through periodic pre-scheduling in a specific time domain and frequency domain, the present invention realizes signaling communication without data interaction. This method reduces the dependence on traffic during communication. Compared with the prior art solutions that obtain user identities through data transmission, the present invention avoids the problem of data traffic consumption and solves the deficiency of high communication costs in traditional methods.

[0042] 2. By combining the pre-scheduling strategy, the present invention ensures that the signals between the target terminal and non-target users do not interfere with each other. Through continuous scheduling of fixed resources, the stability of the link is maintained. Compared with the prior art solutions where the positioning accuracy is greatly affected by the complex network environment, the present invention improves the positioning accuracy within a specific coverage area and overcomes the problem of large positioning errors in the prior art.

[0043] 3. Through dynamic resource allocation and multi-angle scanning technology of directional antennas, the present invention can adapt to various actual scenarios. Compared with the prior art where the system deployment is complex and the debugging cycle is long, the present invention can complete system deployment in a short time. Especially in emergency scenarios such as maritime rescue or earthquake search and rescue, the present invention solves the problem of long deployment response time in the prior art.

[0044] 4. By using the path loss model and direction determination algorithm, the present invention gradually approaches the position of the target terminal. Compared with the prior art positioning methods that rely on high power consumption or complex hardware, the present invention achieves precise positioning with low power consumption and high flexibility, and solves the deficiencies of excessive power consumption and inapplicability to mobile scenarios in traditional technologies. Description of the Drawings

[0045] Figure 1 is the flowchart of the method steps of the present invention;

[0046] Figure 2 is the distribution diagram of the device modules of the present invention. Detailed Embodiments

[0047] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0048] Embodiment 1:

[0049] Please refer to the appendix Figure 1 , the embodiment of the present invention provides a method for a mobile terminal to capture IMSI and locate based on the NR system, including the following steps:

[0050] S1. Start the base station and configure the coverage range and specific parameters of the NR network, including the TDD time slot ratio in the time domain and the resource block position in the frequency domain;

[0051] S2. Receive the RRC connection request sent by the mobile terminal within the coverage range of the base station and complete the establishment of the communication link;

[0052] S3. The base station sends an identity request signaling to the mobile terminal and receives the identity response signaling returned by the mobile terminal, which contains the subscriber privacy identifier of the mobile terminal, namely SUCI;

[0053] S4. The base station decodes the SUCI into the international mobile subscriber identification number, namely IMSI, and determines whether the IMSI is the target user;

[0054] S5. For the target user, the base station performs periodic pre-scheduling on the target terminal in the fixed time domain and frequency domain to maintain the stable connection of the link and avoid interfering with non-target users;

[0055] S6. The base station gradually determines the position of the target terminal by combining the signal strength fed back by the target terminal, the direction information of the directional antenna and the signal strength change information;

[0056] The pre-scheduling in step S5 includes:

[0057] In the time domain, the base station schedules the target terminal at a fixed subframe position;

[0058] In the frequency domain, the base station allocates a specific resource block range for the target terminal, and the signaling scheduling of non-target terminals avoids this frequency domain;

[0059] The period of the pre-scheduling is 10 ms, and the base station maintains signaling interaction with the target terminal within each period without generating data traffic;

[0060] The target terminal positioning in step S6 includes the following contents:

[0061] The base station receives the signal strength periodically reported by the target terminal;

[0062] Determine the maximum direction of the target terminal signal strength through multi-angle scanning of the directional antenna;

[0063] Determine the distance between the base station and the target terminal according to the signal strength;

[0064] Combining direction and distance information, gradually approaching the position of the target terminal;

[0065] The signal strength of the target terminal received by the base station changes inversely with distance, and through the smoothing process of the feedback signal;

[0066] This method is applicable to specific scenarios under the NR network, including application scenarios such as maritime rescue, forest and grassland protection, criminal investigation, post-disaster positioning, etc.;

[0067] The directional antenna of the base station has the ability to scan at multiple angles, and supports the target positioning task in a dynamic environment in combination with the movement direction of the base station.

[0068] Specifically, the implementation of step S1 aims to complete the initialization operation of the base station startup by reasonably configuring the communication parameters of the base station and the mobile terminal, providing an accurate parameter basis and communication environment for subsequent steps. In this technical solution, the configuration of the base station needs to combine the network coverage range, resource allocation parameters in the time domain and frequency domain to ensure that the target terminal can establish a stable communication link with the base station. To achieve this goal, the base station initialization needs to reasonably plan specific time slot ratios, resource block positions, and other communication protocol parameters to ensure the efficiency and stability of the initialization process.

[0069] Specifically, in this embodiment, step S1 includes the startup of the base station and the configuration process of key parameters. Generally, the initialization of the base station includes the detection of the communication environment and the setting of basic parameters, such as the planning of the coverage range, the time slot ratios of the uplink and downlink, the resource block allocation range, etc.

[0070] As an option, the coverage range of the base station can be dynamically adjusted according to the distribution of the target terminal and environmental conditions. In one possible implementation, the time slot configuration ratio of the NR network needs to be considered during the base station initialization. For example, the TDD time slot ratio is set to 6:4:4 to meet the communication requirements of the target terminal. Specifically, this ratio can balance the resource allocation of the uplink and downlink communication links.

[0071] In some other embodiments, the resource block range during the base station initialization needs to be reasonably planned according to the frequency domain allocation situation. For example, in the RB (Resource Block) allocation, the frequency domain resources can be fixed within the range of RB41 to RB46 for the communication requests and signal interactions of the target terminal. The selection of the frequency domain position can avoid signal interference from non-target users and improve the stability of communication.

[0072] In addition, specific subframe positions need to be set during the initialization process. Specifically, the base station can select a fixed uplink subframe position (such as subframe 8) as the basic time-domain position for communication interaction. In some embodiments, the fixed setting of the subframe can provide a stable communication window for the target terminal, ensuring the continuity of signaling interaction.

[0073] In one possible implementation, the base station also needs to load initialization parameters during startup, including resource allocation configuration files in the time domain and frequency domain, power sensitivity setting values, and antenna direction parameters, etc. Specifically, the setting of power sensitivity needs to be combined with the estimated distance range of the target terminal. For example, the sensitivity of the base station can be set to detect signals in the range of -110dBm to -85dBm, ensuring accurate capture of signals from target terminals at both long and short distances.

[0074] As an application example, when the coverage range of the base station is large, the antenna direction can be adjusted according to the actual scenario. For example, the base station can use directional antennas to cover the target area from multiple angles, and further improve the flexibility of the initialization configuration by adjusting the scanning rate of the antenna angle. In some embodiments, this dynamic adjustment of the antenna direction can also be combined with the distribution of field strength signals to optimize the signal strength within the coverage range.

[0075] In the formula part, the initialization parameters required in this embodiment can be calculated by the following formula:

[0076] ;

[0077] Where:

[0078] represents the detection power threshold of the base station;

[0079] represents the minimum sensitivity of the base station;

[0080] represents the maximum distance of the base station coverage range.

[0081] The goal of step S2 is to establish a communication link between the base station and the mobile terminal. This process is of great significance for realizing subsequent signaling interaction and positioning operations. Specifically, step S2 needs to ensure that the target terminal can successfully access within the coverage range of the base station, while avoiding interference and resource conflicts from non-target users.

[0082] In this embodiment, the main task of step S2 is to receive the RRC (Radio Resource Control) connection request sent by the mobile terminal and complete the establishment of the communication link. Generally, the establishment of the RRC connection requires the base station to gradually complete resource allocation and state switching in combination with the protocol stack and signaling process of the NR network.

[0083] Specifically, after receiving the broadcast channel information from the base station, the mobile terminal will initiate an RRC connection request based on pre-configured random access resources. As an option, during the random access process, the mobile terminal will send a random access preamble through the Physical Random Access Channel (PRACH). After detecting the preamble, the base station will send a random access response through the Physical Downlink Control Channel (PDCCH), which contains the allocation information of random access resources and timing alignment information.

[0084] In a possible implementation, after completing the initial steps of random access, the base station will allocate specific time-domain and frequency-domain resources for the target terminal to complete further processing of the RRC connection request. For example, the base station can allocate exclusive signaling interaction resources for the target terminal at a fixed subframe position in the time domain (such as subframe 8) and a resource block range in the frequency domain (such as RB41 to RB46). Such a resource allocation method can effectively avoid resource competition among non-target users and provide guarantee for subsequent link stability.

[0085] In some embodiments, to improve the efficiency of communication link establishment, the base station can estimate the distance of the target terminal based on its initial signal power and adjust the timing parameters of the random access response accordingly. Specifically, the base station can calculate the distance of the target terminal according to the following formula:

[0086] ;

[0087] Where:

[0088] represents the distance between the base station and the target terminal;

[0089] is the speed of light, in meters per second;

[0090] is the propagation delay of the signal, in seconds.

[0091] In another implementation, to further improve the success rate of RRC connection, the base station can optimize the random access process by adjusting the power control parameters. For example, the base station can calculate the power control offset value of the target terminal according to the following formula:

[0092] ;

[0093] Where:

[0094] represents the transmission power of the target terminal;

[0095] is the initial power value;

[0096] is the power control bias, which is dynamically adjusted based on the feedback signal of the base station.

[0097] As an option, after the random access is completed, the base station will switch the target terminal from the RRC idle state to the RRC connected state. Specifically, the base station notifies the target terminal to enter the connected state by sending an RRC connection establishment confirmation message (RRCConnectionSetupComplete), and allocates dedicated control and data resources for it.

[0098] Generally, the base station needs to handle connection requests of multiple terminals simultaneously during the link establishment process in step S2. Therefore, the base station needs to combine the resource scheduling algorithm and the priority policy to ensure that the connection request of the target terminal can be processed preferentially. For example, in a high-load scenario, the base station can sort the connection requests according to the IMSI priority of the terminals and allocate resources to the target terminals with high priority first.

[0099] Step S3 aims to obtain the subscriber privacy identifier (SUCI) of the target terminal through signaling interaction. The acquisition of SUCI is a prerequisite for further decoding the international mobile subscriber identity (IMSI) of the target terminal, which is related to the identity confirmation of the target terminal and the accuracy of subsequent positioning operations. This process requires the base station to perform signaling interaction with the target terminal according to the communication protocol, send an identity request signaling, and receive the identity response signaling returned by the terminal.

[0100] In this embodiment, the identity request signaling sent by the base station adopts the message format of the NAS (Non-Access Stratum) layer in the NR network protocol. Generally, the identity request signaling of the NAS layer carries a flag field requesting the target terminal to return the subscriber privacy identifier, which is used to indicate the terminal to perform a specific type of identity authentication.

[0101] Specifically, the base station marks the "IdentityRequest" type in the signaling to request the target terminal to return the SUCI. As an option, the base station can also specify the required identity identifier category in the request signaling, such as "SUCI" or "GUTI (Globally Unique Temporary Identifier)". This option can be dynamically adjusted according to the current state of the network and the access mode of the target terminal.

[0102] In a possible implementation, after receiving the identity request signaling, the target terminal will generate the SUCI according to the network configuration parameters and return it to the base station through the identity response signaling of the NAS layer. Specifically, the generation of SUCI depends on the IMSI of the target terminal and the encryption parameters.

[0103] In some embodiments, after receiving the SUCI, the base station will parse it and complete the decryption operation in combination with the private key of the home network, thereby restoring the IMSI of the target terminal.

[0104] In another implementation, to improve the success rate of SUCI acquisition, the base station can dynamically adjust the sending timing of the identity request signaling in combination with the result of the random access process. For example, the base station can immediately send the identity request signaling after the initial access signaling interaction of the target terminal is completed, so as to reduce the signaling delay.

[0105] As an application example, when the target terminal returns the SUCI, it can also carry other network parameters, such as the reported signal strength or the current mobile state. These parameters can provide additional information support for the subsequent positioning module. For example, the signal strength value of the target terminal can be calculated by the following formula:

[0106] ;

[0107] Where:

[0108] is the signal strength reported by the target terminal;

[0109] is the signal strength received by the base station;

[0110] is the path loss value.

[0111] Generally, after the base station completes the SUCI acquisition, it will store this identifier for subsequent operations. At the same time, the base station needs to determine whether the acquired SUCI meets the identity requirements of the target user. For example, in some embodiments, the base station can verify whether the target terminal belongs to the current network by comparing the home network identifiers (MCC and MNC) of the IMSI prefix.

[0112] The core task of step S4 is to decode the SUCI to restore the International Mobile Subscriber Identity (IMSI) of the target terminal. The decoding of the IMSI is an important link for realizing the identity confirmation of the target user, and its accuracy is directly related to the subsequent positioning and pre-scheduling operations. The base station needs to combine the private key of the home network and use the encryption and decryption algorithm to process the SUCI, so as to obtain the IMSI information.

[0113] In this embodiment, the SUCI received by the base station is generated by the target terminal through an encryption algorithm, and contains the encrypted content of the IMSI and the necessary key information. Generally, the decoding of the SUCI depends on the encryption and decryption algorithms shared by the base station and the target terminal. For example, in the 5G network, the decryption of the SUCI usually uses the Elliptic Curve Cryptography (ECC) algorithm or the asymmetric encryption algorithm.

[0114] Specifically, when decoding the SUCI, the base station needs to call the private key of the home network and combine it with the received encrypted SUCI data to complete the recovery operation of the IMSI.

[0115] As an option, after the decoding is completed, the base station will verify the recovered IMSI information to ensure the correctness of the decoding result. In some embodiments, the base station will compare the prefix (MCC and MNC) of the IMSI with the configuration parameters of the target network to verify whether the IMSI belongs to the expected target user.

[0116] In a possible implementation, after decoding the IMSI, the base station can directly determine the identity priority of the target terminal. For example, high-priority IMSI users may correspond to emergency rescue tasks or special application scenarios. In this case, the base station will allocate more resources to ensure the stability of the communication link.

[0117] To improve the efficiency of SUCI decoding, in some embodiments, the base station will combine hardware acceleration technologies, such as using dedicated encryption and decoding chips or algorithm optimization modules, to accelerate the decoding process. In addition, the parameter ranges that may be involved in the decoding process are as follows:

[0118] ;

[0119] Where:

[0120] is the time delay of SUCI decoding, in milliseconds.

[0121] In another implementation, the base station will record other auxiliary information related to the IMSI during the decoding process, such as the delay statistics or key usage status during the decoding process. This information can provide additional support for subsequent positioning and pre-scheduling modules. For example, when the IMSI of the target user is successfully decoded, the base station can immediately allocate a specific resource block for continuous signaling interaction.

[0122] Generally, the decoding of the SUCI must ensure security and reliability. In some embodiments, to prevent decoding failures or data loss, the base station will also perform redundant backups on the decoding process. Specifically, the base station can store the decoded IMSI in a temporary database and synchronize it with the core network of the system to ensure data consistency.

[0123] The main objective of step S5 is to perform periodic pre-scheduling operations on the target terminal. Through specific time-domain and frequency-domain allocations, the base station can maintain the communication link with the target terminal while avoiding interference to non-target users. This process provides the necessary signaling interaction guarantee for subsequent signal acquisition and positioning modules.

[0124] In this embodiment, when the base station performs pre-scheduling on the target terminal, it needs to allocate communication resources within a fixed time-domain subframe and frequency-domain resource block range. Generally, the pre-scheduling period is fixed at 10 ms to ensure continuous signaling interaction between the base station and the target terminal without generating data traffic.

[0125] Specifically, the base station will select a specific uplink subframe position in the time domain, such as subframe 8. As an option, this fixed time-domain position helps the target terminal maintain time synchronization in periodic signaling reporting, avoiding loss or duplication of signaling interaction.

[0126] In the frequency domain, the base station allocates a specific resource block range for the target terminal, such as RB41 to RB46. These resource block ranges are isolated from the resource allocation of non-target users to avoid signal interference. In some embodiments, the base station will dynamically adjust the resource block range to adapt to the network load status or coverage area where the target terminal is located.

[0127] In a possible implementation, after completing the time-domain and frequency-domain allocations, the base station will also set a power reporting mechanism for the pre-scheduling signaling. The target terminal needs to return signal power information in each scheduling period, and the base station dynamically adjusts the pre-scheduling parameters by analyzing these reported power values. The calculation formula for power reporting is as follows:

[0128] ;

[0129] Where:

[0130] represents the signal power reported by the target terminal;

[0131] represents the transmit power allocated by the base station;

[0132] represents the path loss.

[0133] Generally, the power reporting mechanism can help the base station perceive the communication status of the target terminal in real time and optimize the pre-scheduling results according to the signal strength change.

[0134] In another implementation, the base station will adopt a certain dynamic frequency hopping strategy for the frequency-domain allocation of pre-scheduling. For example, when the signal strength of the target terminal is lower than a certain threshold, the base station can select a new frequency-domain resource block range to reduce the impact of path interference on the communication link.

[0135] As an option, during the pre-scheduling process, the base station also needs to consider the overall network load. In some embodiments, the base station can preferentially meet the communication requirements of the target terminal through hierarchical scheduling. For example, in a high-load scenario, the base station will prioritize resource allocation for the target terminal and transfer the signaling interaction of non-target users to other resource block ranges.

[0136] The task of step S6 is to locate the target terminal. By combining the signal strength and direction information fed back by the target terminal, the base station can gradually determine the specific location of the target terminal. The accuracy of the positioning process is directly related to the overall performance of the system, especially in dynamic or complex scenarios.

[0137] In this embodiment, the base station preliminarily determines the distance of the target terminal through the acquisition and analysis of signal strength. Generally, the magnitude of the signal strength is inversely proportional to the distance between the target terminal and the base station. The base station calculates the distance of the target terminal in combination with the path loss model. The specific formula is as follows:

[0138] ;

[0139] Where:

[0140] represents the distance between the base station and the target terminal;

[0141] is the transmit power of the base station;

[0142] is the received signal strength reported by the target terminal;

[0143] is the correction factor for antenna gain and path loss;

[0144] is the path loss exponent.

[0145] Specifically, after obtaining the preliminary distance information, the base station will conduct further analysis in combination with the direction information of the directional antenna. As an option, the directional antenna captures the signal direction of the target terminal through multi-angle scanning. The range and angle step of the multi-angle scanning can be adjusted according to the size and complexity of the target area.

[0146] In a possible implementation, during the scanning process of the base station's antenna, the maximum signal strength at different angles will be recorded. By combining the scanning direction and distance information, the base station can determine the approximate location of the target terminal. In some embodiments, the base station will also smooth the positioning result in combination with the signal strength change within the time window. The smoothing processing formula is as follows:

[0147] ;

[0148] Wherein:

[0149] is the weighted average of the signal strength;

[0150] is the signal strength of the th measurement within the time window;

[0151] is the weight of the th measurement;

[0152] is the number of measurements within the time window.

[0153] Generally, the smoothing process can effectively reduce the signal fluctuations caused by environmental interference and improve the positioning accuracy.

[0154] In another embodiment, the base station will also gradually approach the target terminal in combination with the motion information of the dynamic carrier. For example, the base station can carry a directional antenna by means of a mobile platform (such as a drone or a vehicle), and further reduce the positioning error through multi-point sampling. In some embodiments, the base station will also verify the positioning result, for example, by comparing whether the results of different sampling points are consistent to verify the specific location of the terminal.

[0155] As an option, the base station can dynamically adjust the resource allocation strategy according to the positioning result of the target terminal. For example, when the target terminal approaches the coverage boundary of the base station, the base station will allocate more resources to it to ensure the stability of signaling interaction.

[0156] Embodiment 2:

[0157] Please refer to the appendix Figure 2 , a mobile terminal capturing IMSI and positioning device based on the NR system, including:

[0158] Base station transceiver module: used to receive the RRC connection request of the mobile terminal and complete the establishment of the communication link;

[0159] SUCI acquisition module: used to receive the subscriber privacy identifier returned by the mobile terminal;

[0160] IMSI conversion module: used to decode the SUCI into an international mobile subscriber identification number;

[0161] Link maintenance module: used to perform periodic pre-scheduling on the target terminal within a specific time domain and frequency domain to maintain signaling interaction and avoid interfering with non-target terminals;

[0162] Positioning module: used to gradually locate the target terminal by combining the signal strength fed back by the target terminal with the information of the directional antenna;

[0163] The link maintenance module includes:

[0164] A time-domain scheduling unit for allocating a fixed subframe position to the target terminal;

[0165] A frequency-domain scheduling unit for allocating a fixed resource block range to the target terminal and ensuring that the frequency-domain resource allocation for non-target terminals is separated from that of the target terminal;

[0166] A pre-scheduling unit for periodically scheduling the signaling interaction of the target terminal every 10 ms to ensure a continuous link connection and no data traffic consumption;

[0167] The positioning module includes:

[0168] A signal reception unit for receiving the signal strength feedback from the target terminal;

[0169] A direction determination unit for determining the direction where the target terminal is located through the direction change information of the signal strength;

[0170] A distance calculation unit for estimating the distance between the target terminal and the base station according to the relationship between the signal strength and the distance;

[0171] A positioning analysis unit for gradually determining the position of the target terminal by combining the direction and distance information;

[0172] The signal reception unit of the positioning module is also used to perform weighted smoothing processing on the signal strength feedback value with a fixed time window to reduce the influence of signal fluctuations on the positioning accuracy.

[0173] Specifically, the base station transceiver module is mainly responsible for the signaling interaction with the mobile terminal and the establishment of the communication link. In this technical solution, this module needs to support the communication requirements under the NR network protocol and complete the whole process from the broadcast channel transmission, random access response to the establishment of the RRC connection. The performance of the base station transceiver module directly affects the overall stability of the system and the accuracy of resource scheduling.

[0174] In this embodiment, the main task of the base station transceiver module is to process the access request of the target terminal and complete the link establishment according to the preset communication parameters. Generally, the base station sends the system information of the network through the physical broadcast channel (PBCH), including basic parameters such as frequency, resource block allocation, and time-domain configuration. The target terminal initiates a random access request according to the received system information to complete the initial access.

[0175] As an option, when processing the random access signaling, the base station transceiver module will monitor the preamble sent by the target terminal through the physical random access channel (PRACH). Specifically, the base station judges the access timing of the target terminal and performs time-domain alignment according to the time-domain position and power characteristics of the preamble.

[0176] In a possible implementation, the base station sends a random access response message to the target terminal via the physical downlink control channel (PDCCH), which includes the allocated resource block range and time domain alignment information. For example, resources are allocated to the target terminal within the frequency domain range of RB41 to RB46, and signaling interaction is performed at the time domain position of subframe 8.

[0177] To improve the efficiency of communication link establishment, the base station transceiver module can also adjust access parameters by combining signal power and delay feedback. Specifically, the base station can estimate the propagation delay of the target terminal according to the following formula:

[0178] ;

[0179] where:

[0180] represents the propagation delay of the signal;

[0181] represents the distance between the base station and the target terminal;

[0182] represents the speed of light.

[0183] In some embodiments, to ensure the stability of signaling interaction, the base station transceiver module also supports power control feedback for the target terminal. For example, the base station can dynamically adjust the transmit power of the target terminal according to the received signal strength. The power adjustment formula is as follows:

[0184] ;

[0185] where:

[0186] represents the adjusted transmit power of the target terminal;

[0187] is the current transmit power;

[0188] is the power adjustment amount calculated by the base station.

[0189] Generally, after the base station transceiver module completes the random access process, it will initiate the RRC connection establishment process. Specifically, the base station establishes a stable signaling link with the target terminal through RRC connection request and confirmation messages. In some embodiments, the base station transceiver module will also store the access status and resource allocation of the target terminal for subsequent scheduling and positioning modules to use.

[0190] As an application example, the base station transceiver module can also dynamically adjust the access policy according to the IMSI priority of the target terminal. For example, for high-priority target users, the base station can reserve a larger range of resource blocks to ensure that the access delay and signaling stability are better than those of ordinary users.

[0191] The core task of the SUCI acquisition module is to obtain the Subscriber Privacy Identifier (SUCI) from the target terminal through signaling interaction, providing data support for subsequent IMSI decoding and target terminal identity confirmation. This module works in coordination with the base station transceiver module and utilizes the signaling interaction process in the network protocol to achieve efficient SUCI acquisition while ensuring data security.

[0192] In this embodiment, the work of the SUCI acquisition module includes sending an identity request signaling and receiving an identity response signaling from the target terminal. Generally, the identity request signaling is sent through the NAS (Non-Access Stratum) layer, carrying the identity identifier type and request parameters. Specifically, this signaling is marked with the "IdentityRequest" message type and clearly requests the target terminal to return the SUCI.

[0193] As an option, the SUCI acquisition module can dynamically adjust the parameters in the identity request signaling, such as the category of the request identifier or the related timeout setting. In some embodiments, when the network is in a low-load state, the base station will preferentially request the target terminal to return the SUCI to reduce the signaling interaction delay.

[0194] In a possible implementation, after receiving the identity request signaling, the target terminal generates the SUCI according to the network configuration and returns it to the base station through the identity response signaling of the NAS layer.

[0195] Generally, the encryption process of the SUCI ensures the security of the IMSI during transmission, avoiding the leakage of user privacy.

[0196] Specifically, after receiving the response signaling returned by the target terminal, the SUCI acquisition module will parse the signaling content, extract the SUCI value, and store it in a temporary cache. In some embodiments, the base station will also perform a simple verification on the received SUCI, such as verifying its format or encryption integrity, to ensure the validity of the data.

[0197] In another implementation, the SUCI acquisition module will record the timestamp and signaling path information of the signaling interaction, which is used to analyze the delay or other potential problems in the SUCI acquisition process. For example, by recording the sending time of the identity request signaling and the receiving time of the response signaling, the signaling round-trip delay can be calculated, and the formula is as follows:

[0198] ;

[0199] Wherein:

[0200] is the delay time of signaling interaction;

[0201] represents the timestamp for receiving the response signaling;

[0202] represents the timestamp for sending the request signaling.

[0203] As an option, the SUCI acquisition module can also cooperate with the core network of the system to decrypt and verify the encryption structure of the SUCI using the key of the home network. For example, when the SUCI received by the base station contains errors or is incomplete, a retransmission can be requested through the verification process of the core network.

[0204] In some embodiments, to improve the success rate of SUCI acquisition, the SUCI acquisition module analyzes the signaling interaction records of the target terminal and adjusts the signaling retransmission times or intervals. For example, when the signal strength of the target terminal is weak, the module can extend the signaling timeout to ensure the integrity of data transmission.

[0205] The main task of the IMSI conversion module is to recover the IMSI of the target terminal through the decryption and parsing process using the SUCI data obtained by the base station from the target terminal. The successful decoding of the IMSI is crucial for subsequent target user confirmation and positioning. This module is closely connected to the SUCI acquisition module and completes the IMSI conversion operation by calling the decryption algorithm and the private key of the home network.

[0206] In this embodiment, the IMSI conversion module decrypts the SUCI by calling the private key of the home network. Generally, the encryption structure of the SUCI uses an asymmetric encryption algorithm, where the public key of the home network is used when the target terminal generates the SUCI.

[0207] As an option, the IMSI conversion module checks the integrity of the SUCI before the decryption operation. For example, the module can check whether the SUCI data conforms to a predetermined format or contains necessary fields. This check can effectively avoid decoding failures caused by data transmission errors.

[0208] In a possible implementation, the IMSI conversion module manages the keys used in the decryption process by combining the cooperation of network core devices. For example, when the SUCI decryption fails, the module can request a key update from the core network and re - execute the decryption operation. In some embodiments, to improve the decryption efficiency, the module can also complete complex calculation processes through a hardware acceleration unit (such as a dedicated decryption chip).

[0209] Specifically, after successfully decrypting the SUCI, the IMSI conversion module also parses the home network identifiers (MCC and MNC) of the IMSI to verify whether the IMSI belongs to the home network of the target user. Generally, the first 6 digits of the IMSI represent the country code (MCC) and operator code (MNC) of the home network respectively.

[0210] In some embodiments, to further confirm the authenticity of the IMSI, the IMSI conversion module can also perform multi-dimensional verification on the decoded IMSI by combining the access status records of the base station and the signaling path information. For example, the module can compare the IMSI with the list of legitimate users within the coverage of the base station to ensure the uniqueness and traceability of the target terminal's identity.

[0211] As an application example, the IMSI conversion module can also encrypt and store the decoding result of the IMSI to ensure data security when subsequent modules call it. In some embodiments, the module encrypts the IMSI data and stores it in a temporary memory, and sets the storage validity period. For example, when the storage time of the IMSI exceeds the preset threshold, the module automatically clears the stored data to avoid data leakage.

[0212] The link maintenance module realizes the continuous link connection of the target terminal and avoids resource conflicts with non-target users through specific time-domain and frequency-domain resource allocation and periodic scheduling strategies. This module directly receives the output result of the IMSI conversion module and provides a reliable communication foundation for the subsequent positioning module through dynamic resource scheduling of the target terminal.

[0213] In this embodiment, the working process of the link maintenance module includes performing periodic pre-scheduling operations within a specific frequency domain and time domain. Generally, the base station allocates exclusive resource blocks and sub-frame positions for the target terminal according to the IMSI information of the target terminal. Specifically, the frequency-domain resources can be configured within the range of RB41 to RB46, and the time-domain position can be selected as the fixed uplink sub-frame 8 for signaling interaction.

[0214] As an option, the link maintenance module supports dynamically adjusting the scheduling period to adapt to network state changes. In some embodiments, the module fixes the scheduling period at 10 ms to maintain the signaling interaction stability of the target terminal and avoid unnecessary resource waste. The selection of the scheduling period can be flexibly adjusted according to the signal feedback of the target terminal to optimize the communication efficiency.

[0215] In a possible implementation, the link maintenance module dynamically optimizes the pre-scheduling parameters using the power reporting information of the target terminal. For example, the path loss of the target terminal is calculated by the following formula:

[0216] ;

[0217] Wherein:

[0218] is the path loss;

[0219] represents the signal power transmitted by the base station;

[0220] is the signal reception power reported by the target terminal.

[0221] Generally, the link maintenance module dynamically adjusts the power level or resource allocation range of the target terminal by analyzing the path loss value. For example, when the path loss is too large, the module increases the transmission power or expands the range of frequency domain resource blocks to enhance communication stability.

[0222] Specifically, the link maintenance module also detects the signaling interference situation of non-target users in real time and avoids interference by separating the resource allocation of the target and non-target users. In some embodiments, the module dynamically adjusts the time domain subframe position of the target terminal according to the resource usage situation of non-target users, thereby ensuring the exclusivity of the communication link.

[0223] In another implementation, the link maintenance module supports power smoothing processing to reduce the impact of signal fluctuations on link stability. The smoothed signal strength value of the target terminal can be calculated through the following formula:

[0224] ;

[0225] Wherein:

[0226] is the smoothed signal strength value;

[0227] is the single signal strength measurement value within the time window;

[0228] is the weight factor;

[0229] is the number of measurements within the time window.

[0230] As an application example, the link maintenance module also supports dynamic management of the priority of the target terminal. For example, when there are multiple target users within the coverage area of the base station, the module can allocate different resources according to the priority of the IMSI to ensure that the communication requirements of high-priority users are preferentially met.

[0231] The positioning module can gradually determine the spatial position of the target terminal by comprehensively analyzing the signal strength and direction information fed back by the target terminal. The positioning module directly receives the signal feedback provided by the link maintenance module and completes the positioning task in combination with the multi-angle scanning ability of the directional antenna.

[0232] In this embodiment, the core task of the positioning module is to gradually approach the position of the target terminal based on the signal strength periodically reported by the target terminal and in combination with the direction information of the directional antenna. Generally, the signal strength of the target terminal is inversely proportional to its distance from the base station.

[0233] As an option, the positioning module captures the maximum intensity direction of the target terminal signal through multi-angle scanning of the directional antenna. Specifically, the antenna scans the coverage area step by step at a preset angle, and initially determines the direction information of the target terminal by recording the signal strength peaks at different angles.

[0234] In a possible implementation, the positioning module combines the results of multiple scans and uses a weighted average algorithm to smooth the signal direction, further improving the accuracy of direction determination.

[0235] Generally, after obtaining the direction information, the module also performs comprehensive positioning in combination with the distance information calculated from the signal strength. In some embodiments, the positioning module analyzes the trend of the time window change of the signal strength to further improve the positioning accuracy.

[0236] Specifically, the module also supports the target positioning task in a dynamic environment. For example, when the base station is on a moving carrier (such as a vehicle or a drone), the positioning module can adjust the antenna scanning range and step rate in combination with the movement direction and speed information of the carrier to ensure the stability of the positioning result.

[0237] In another implementation, the positioning module can perform multi-point joint analysis on the signal sampling results at different positions to further narrow the position error range of the target terminal. In some embodiments, the module determines the final position of the target terminal by cross-verifying the distance and direction information of multiple sampling points.

[0238] As an application example, the positioning module also supports dynamically adjusting the resource allocation strategy of the link maintenance module according to the positioning result of the target terminal. For example, when the target terminal is close to the edge of the base station coverage, the module can trigger the link maintenance module to allocate more resources to it to ensure the continuous stability of signaling interaction.

[0239] Although embodiments of the present invention have been shown and described, those of ordinary skill in the art will appreciate that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for acquiring and positioning a mobile terminal characteristic value based on an NR system, characterized in that: The following steps are involved: S1. Start the base station and configure the coverage and specific parameters of the NR network, including the TDD time slot ratio in the time domain and the resource block position in the frequency domain; S2. Receive the RRC connection request sent by the mobile terminal within the coverage area of ​​the base station and complete the establishment of the communication link; S3, the base station sends an identity request signaling to the mobile terminal, and receives an identity response signaling returned by the mobile terminal, which includes the subscriber privacy identifier (SUCI) of the mobile terminal; S4, the base station decodes the SUCI into the International Mobile Subscriber Identity (IMSI), and determines whether the IMSI is that of the target user; S5. For the target user, the base station performs periodic pre-scheduling on the target terminal in a fixed time domain and frequency domain to maintain a stable connection of the link; S6. The base station gradually determines the location of the target terminal through the signal strength fed back by the target terminal, combined with the direction information of the directional antenna and the signal strength change information; The pre-scheduling in step S5 includes: In the time domain, the base station schedules the target terminal at a fixed subframe position; In the frequency domain, the base station allocates a specific resource block range to the target terminal, and the signaling scheduling of non-target terminals avoids this frequency domain; The pre-scheduling period is 10ms. The base station maintains signaling interaction with the target terminal in each period, while no data traffic is generated; The target terminal positioning in step S6 includes the following contents: The base station receives the signal strength periodically reported by the target terminal; Through multi-angle scanning of directional antennas, the direction with the maximum signal strength of the target terminal is determined; Determine the distance between the base station and the target terminal based on the signal strength; Combine direction and distance information to gradually approach the location of the target terminal; The directional antenna has multi-angle scanning capability and supports target positioning tasks in dynamic environments in combination with the movement direction of the base station; The directional antenna reduces the influence of signal fluctuation on positioning accuracy by performing weighted smoothing processing on the signal strength feedback value in a fixed time window; The smoothing formula is as follows: in: P avg is the weighted average of signal strength; P i is the signal strength of the ith measurement in the time window; w i is the weight of the i-th measurement; N is the number of measurements in the time window.

2. According to a method for acquiring and positioning a mobile terminal characteristic value based on an NR system according to claim 1, it is characterized in that: The signal strength of the target terminal received by the base station varies inversely with the distance, and is processed by smoothing the feedback signal.

3. According to a method for acquiring and positioning a mobile terminal characteristic value based on an NR system according to claim 1, it is characterized in that: This method is applicable to specific scenarios under the NR network, including maritime rescue, forest and grassland protection, crime investigation and post-disaster positioning application scenarios.

4. A mobile terminal feature value acquisition and positioning device based on the NR system, according to a mobile terminal feature value acquisition and positioning method based on the NR system according to any one of claims 1 to 3, characterized in that: include: Base station transceiver module: used to receive the RRC connection request from the mobile terminal and complete the establishment of the communication link; SUCI acquisition module: used to receive the subscriber privacy identifier returned by the mobile terminal; IMSI conversion module: used to decode SUCI into international mobile subscriber identity; Link maintenance module: used to perform periodic pre-scheduling of the target terminal in a specific time domain and frequency domain to maintain signaling interaction and avoid interference with non-target terminals; Positioning module: used to gradually locate the target terminal through the signal strength fed back by the target terminal and the information of the directional antenna.

5. According to claim 4, a mobile terminal feature value acquisition and positioning device based on the NR system is characterized in that: The link maintenance module comprises: a time domain scheduling unit, used to allocate fixed subframe positions to target terminals; a frequency domain scheduling unit, configured to allocate a fixed resource block range to a target terminal and ensure that frequency domain resource allocations of non-target terminals are separated from those of the target terminal; A pre-scheduling unit is used to periodically schedule the target terminal signaling interaction every 10ms to ensure continuous link connection without data traffic consumption.

6. According to the NR system-based mobile terminal feature value acquisition and positioning device according to claim 4, it is characterized in that: The positioning module comprises: A signal receiving unit, used to receive signal strength feedback from a target terminal; A direction determination unit, used to determine the direction of the target terminal through the direction change information of the signal strength; A distance calculation unit, used to estimate the distance between the target terminal and the base station based on the relationship between signal strength and distance; The positioning analysis unit is used to gradually determine the location of the target terminal by combining direction and distance information.

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