Positioning system, network device for positioning, control circuit, storage medium, and positioning method

Abstract

Has: estimated position calculation section (112), which calculates the estimated position of mobile station (100); database (115), which saves information indicating areas in which mobile station (100) can be in service range, information indicating anchor points utilized in each area, and information of communication parameters; Area determination section (113), which determines the area to which mobile station (100) belongs based on the estimated position of mobile station (100) and the information of database (115); Utilize anchor point decision section (114), which decides the anchor point utilized by mobile station (100) based on the area to which mobile station (100) belongs and the information of database (115); Positioning information acquisition section (116), which acquires positioning information indicating the positional relationship between the decided anchor point and mobile station (100); And position calculation section (117), which calculates the position of mobile station (100) based on the positioning information and the information of database (115).

Description

Technical Field

[0001] This invention relates to a positioning system for locating the position of a mobile station, a positioning network device, a mobile station, a control circuit, a storage medium, and a positioning method. Background Technology

[0002] In recent years, the demand for accurately determining the position of moving objects for application purposes has been increasing. As an example, in autonomous driving, the precise location of vehicles on the road is determined, and lane changes are made based on a road map to guide the vehicles to their destination. Automated Guided Vehicles (AGVs) in factories are systems based on the same concept, utilizing the vehicle's position information to accurately deliver loaded goods to their destinations within the factory.

[0003] Autonomous driving systems and other applications used in vast outdoor areas have traditionally relied on GNSS (Global Navigation Satellite System), represented by GPS (Global Positioning System) satellites. While GNSS can provide positioning services over wide areas, it also presents challenges, such as in locations where visual confirmation of satellite positioning is impossible, including underground, tunnels, elevated structures, and indoor parking lots. To address these challenges, recent years have seen the emergence of infrastructure-based positioning services utilizing short-range wireless technologies such as mobile phone base stations, wireless LAN (Local Area Network) access points, and Bluetooth (a registered trademark).

[0004] For example, Patent Document 1 discloses a technique that uses base stations deployed in a wide area to determine a group of base stations within a certain range as a first group based on the estimated location of the mobile device. The interference between base stations in the same group is estimated based on parameters such as the transmission position on the time and frequency axis of the positioning reference signal. Based on the estimation result, the base station used for positioning is determined, and the location of the mobile device is calculated.

[0005] Patent Document 1: Japanese Patent Publication No. 2018-502276 Summary of the Invention

[0006] Wireless applications are rapidly increasing, and the shortage of frequency resources has become a problem. In addition to the existing data communication needs, applications that use wireless signals for positioning, sensing, and other purposes are also increasing, seeking efficient positioning methods and wireless applications.

[0007] However, the aforementioned existing technologies are based on the premise of using public-facing wireless infrastructure. While these technologies utilize databases to extract candidate base station groups and candidate transmitting station groups for positioning based on estimated locations of mobile devices, they require subsequent connections with each base station or the transmission of probe information to obtain various wireless parameters, and then filtering the wireless base stations actually used for positioning to perform mobile device positioning. Therefore, the following problems exist: delays in positioning processing associated with the selection of target base stations are generated, consuming wireless resources.

[0008] The present invention is made in view of the above circumstances, and its object is to provide a positioning system that can suppress the processing delay required for positioning and suppress the consumption of wireless resources.

[0009] To address the aforementioned issues and achieve the objectives, the positioning system of the present invention is characterized by comprising: an estimated location calculation unit that calculates the estimated location of a mobile station; a database that stores information representing the geographical locations of areas within the service range of the mobile station, information representing anchor points used for positioning the mobile station in each area, and information on communication parameters required for communication between the mobile station and anchor points or for measuring positioning signals from anchor points; and an area determination unit that determines the area to which the mobile station belongs based on the estimated location of the mobile station and the information stored in the database. Furthermore, the positioning system includes: an anchor point determination unit that determines the anchor points used by the mobile station in measuring communication or positioning signals based on the area to which the mobile station belongs and the information stored in the database; a positioning information acquisition unit that acquires positioning information representing the positional relationship between the determined anchor points and the mobile station through communication with the determined anchor points or for measuring positioning signals from the determined anchor points; and a location calculation unit that calculates the location of the mobile station based on the positioning information and the information stored in the database.

[0010] The effects of the invention

[0011] The positioning system of the present invention achieves the effect of suppressing the processing delay required for positioning and suppressing the consumption of wireless resources. Attached Figure Description

[0012] Figure 1 This is a diagram illustrating a structural example of the wireless communication system according to Embodiment 1.

[0013] Figure 2 This is a block diagram illustrating a structural example of the positioning system of the mobile station according to Embodiment 1.

[0014] Figure 3 This is a flowchart illustrating the operation of the positioning system involved in Implementation 1.

[0015] Figure 4This is a diagram illustrating an example of the region information stored in the database involved in Implementation 1.

[0016] Figure 5 This is a diagram illustrating an example of anchor point information stored in the database involved in Implementation Method 1.

[0017] Figure 6 This is a diagram illustrating an example of the structure of a processing circuit in the case where the processing circuit of the positioning system according to Embodiment 1 is implemented by a processor and a memory.

[0018] Figure 7 This is a diagram illustrating an example of a processing circuit in the case where the positioning system according to Embodiment 1 is constructed with dedicated hardware.

[0019] Figure 8 This is a block diagram illustrating a structural example of the positioning system according to Embodiment 2.

[0020] Figure 9 This is a flowchart illustrating the operation of the positioning system involved in Implementation Method 2.

[0021] Figure 10 This is a flowchart illustrating the actions taken in the positioning system according to Implementation Method 3 when a mismatch occurs between the database and the actual communication state. Detailed Implementation

[0022] Hereinafter, based on the accompanying drawings, a positioning system, a positioning network device, a mobile station, a control circuit, a storage medium, and a positioning method according to embodiments of the present invention will be described in detail.

[0023] Implementation Method 1

[0024] In this embodiment, base stations, access points, transmitting stations, tags, etc., which are set up as positioning infrastructure, are collectively referred to as anchor points. Additionally, wireless base stations, mobile devices, etc., which are the objects of location estimation, are collectively referred to as mobile stations. Figure 1 This is a diagram illustrating a structural example of the wireless communication system 1 according to Embodiment 1. The wireless communication system 1 includes a mobile station 100 and anchor points 200-1 to 200-6. The mobile station 100 performs its own positioning. Anchor points 200-1 to 200-6 are disposed around the perimeter of the mobile station 100. In the following description, anchor points 200-1 to 200-6 are sometimes referred to as anchor point 200 without distinguishing between them. Figure 1In the example, six anchor points 200 are set, from 200-1 to 200-6. Zones 300-A to 300-H are hypothetical, geographically specific representing areas divided in a planar or spatial manner. In the following description, Zones 300-A to 300-H are sometimes referred to as Zone 300 without distinguishing between them. Figure 1 The example shows eight Zones 300, from Zone 300-A to 300-H. Additionally, "Zone" is sometimes referred to as "region".

[0025] The mobile station 100 determines its current zone 300 based on its estimated location and performs precise positioning by communicating with the anchor point 200 associated with the current zone 300 or by measuring positioning signals from the anchor point 200. Furthermore, the communication-based positioning is envisioned as ranging using propagation time measurements based on timestamps as envisioned in standards such as the IEEE (Institute of Electrical and Electronics Engineers) 802.15.4z standard. The wireless communication system 1 also includes a system in which the mobile station 100 sends a positioning request signal to the anchor point 200 via communication.

[0026] In the context of this embodiment, the ability to privately construct positioning infrastructure utilizing wireless technology is highlighted. Current positioning infrastructure utilizes public-facing systems such as GNSS and mobile phone systems. Therefore, it is difficult to perform customized processing for mobile stations requiring positioning information. On the other hand, in recent years, the system for setting up privately-oriented mobile communication systems such as local 5G (5th Generation), private LTE (Long Term Evolution), and shared XGP (eXtended Global Platform) has been continuously improving. In such systems, the mobile station and the infrastructure equipment are owned by the same entity, allowing for the prior acquisition and utilization of information beneficial to positioning, such as the precise location of the base station and a large amount of configuration parameters. Furthermore, the mobile station's movement route is limited to a certain extent by the specific application of a particular user. Moreover, it is possible to obtain the electromagnetic wave propagation along the movement route using special test modes, thereby creating accurate thermal maps.

[0027] The purpose of this embodiment is to envision achieving efficient positioning by actively utilizing information from various wireless parameters using the private positioning infrastructure described above. As an example, in order to... Figure 1The diagram illustrates positioning within a specific location, i.e., a specific Zone 300, and also allows for the construction of a database indicating which anchor point 200, when communication is established, enables high-precision positioning. In real-world environments, factors such as shielding from buildings and power variations due to multipath propagation can occur; therefore, anchor points 200 that are close or have high power are not necessarily suitable for positioning. Generally, anchor points 200 with guaranteed line-of-sight and minimal reflected waves should be selected. Therefore, Figure 1 The shape of Zone 300 was predicted to be complex rather than simple.

[0028] This describes the specific structure and operation of the mobile station 100, which is used to locate the position of the mobile station 100. Figure 2 This is a block diagram illustrating a structural example of the positioning system 101 included in the mobile station 100 according to Embodiment 1. The mobile station 100 includes a positioning system 101 for locating the position of the mobile station 100. The positioning system 101 includes a positioning control unit 110, a trajectory storage unit 111, a position estimation calculation unit 112, a region determination unit 113, an anchor point determination unit 114, a database 115, a positioning information acquisition unit 116, and a position calculation unit 117. That is, in Embodiment 1, the positioning control unit 110, the trajectory storage unit 111, the position estimation calculation unit 112, the region determination unit 113, the anchor point determination unit 114, the database 115, the positioning information acquisition unit 116, and the position calculation unit 117 are mounted on the mobile station 100. Figure 3 This is a flowchart illustrating the operation of the positioning system 101 according to Embodiment 1.

[0029] If the positioning control unit 110 receives a positioning request from the upper layer or the application, it instructs the mobile station 100 to perform an estimated position calculation on the estimated position calculation unit 112 (step S101).

[0030] The estimated position calculation unit 112 calculates the estimated position of the mobile station 100 using a certain method (step S102). For example, in the case of continuous or periodic positioning, the estimated position calculation unit 112 can utilize the position information from the previous positioning stored in the trajectory storage unit 111. Alternatively, the estimated position calculation unit 112 can also use methods such as acquiring the surrounding conditions based on the camera, comparing the position with various markers, or comparing the position with magnetic markers based on the magnetic sensor. The estimated position calculation unit 112 outputs the calculated estimated position information to the area determination unit 113.

[0031] The region determination unit 113 obtains region information from the database 115. Figure 4This is a diagram illustrating an example of the area information stored in the database 115 according to Implementation Method 1. The area information includes at least information representing the geographical location of each Zone 300. Figure 4 In the case where Zones 300-A and 300-B are formed on a plane, the (X, Y) coordinates of the polygon vertices are notified. The shape of each Zone 300 is arbitrary, and the number of coordinates required to represent each Zone 300 may be different. Furthermore, when Zones 300 are spatially set, the 3D coordinates of (X, Y, Z) are notified. Spatially setting Zones 300 includes cases spanning multiple floors. The zone determination unit 113 determines the Zone 300 to which the mobile station 100 belongs based on the estimated position information obtained from the estimated position calculation unit 112 and the zone information obtained from the database 115 (step S103). The zone determination unit 113 outputs the information of the Zone 300 to which the mobile station 100 belongs to the anchor point determination unit 114.

[0032] The anchor point determination unit 114 determines the anchor point 200 used by the mobile station 100 in measuring communication or positioning signals based on information about the Zone 300 to which the mobile station 100 belongs, obtained from the Zone Determination Unit 113, and area information obtained from the database 115 (step S104). The anchor point determination unit 114 may use, for example, [the following method is used]. Figure 4 The region information in the database 115 shown includes anchor point identification information, which is used to determine the anchor points 200 that should be used for positioning. The anchor point identification information included in the region information is pre-listed as the anchor points 200 that should be used for positioning in each Zone 300. The anchor point determination unit 114 uses the identification information of the determined anchor points 200, for example in... Figure 1 In the example, the anchor point number is output to the positioning information acquisition unit 116.

[0033] The positioning information acquisition unit 116 acquires communication parameters for communicating with each anchor point 200 based on the identification information of the anchor point 200 to be used acquired from the anchor point determination unit 114 and the anchor point information acquired from the database 115. Figure 5 This is a diagram illustrating an example of the anchor point information stored in the database 115 according to Embodiment 1. For each anchor point identification information, the anchor point information includes the location of the anchor point 200 and communication parameters for communicating with the anchor point 200 or measuring the positioning signal from the anchor point 200. The location of the anchor point 200 can be absolute coordinates such as latitude and longitude, or it can be a relative value based on a specific location within a building, space, etc.

[0034] For example, in a wireless communication system 1 based on 3GPP (3rd Generation Partnership Project), the communication parameters include cell ID, such as CGI (Cell Global Identity), as information for identification anchor 200. Additionally, among the communication parameters are various elements of the wireless signal, including center frequency, bandwidth, subcarrier bandwidth, CP (Cyclic Prefix) length, and synchronization signal information based on 3GPP standard TS38.211, i.e., N. ID cell =3N ID (1) +N ID (2) The information includes port number, scramble IDs for DMRS (DeModulation Reference Signals) category generation, PRS (Positioning Reference Signal) resource allocation information, downlink PRS sequence ID, etc. PRS-related information is diverse and cannot be fully recorded. However, as various elements of a radio signal, examples include information notified by the upper layer in the 3GPP system, namely DL (DownLink)-PRS-ID-Info, NR (New Radio)-DL-PRS-AssistanceData, NR-DL-PRS-BeamInfo, NR-DL-PRS-Info, NR-DL-PRS-ResourceID, NR-DL-PRS-ResourceSetID, and NR-SelectedDL-PRS-IndexList. Each element of a radio signal contains one or more of these.

[0035] Furthermore, in the case where the wireless communication system 1 is based on the IEEE 802.15.4 series, the communication parameters include inherent information of the anchor 200, such as the MAC (Media Access Control) address, as information for identifying the anchor 200. In addition, various elements of the wireless signal included in the communication parameters are such as channel number, STS (Scrambled Timestamp Sequence) message structure information, PRF (Pulse Repetition Frequency) mode, preamble, SFD (Start Frame Delimiter) field structure information, PHR (Physical Header) parameter, random number seed, and other STS field structure information. Besides these, it typically includes the wireless base station ID such as the SSID (Service Set Identifier) ​​of the wireless LAN, frequency information such as channel number, center frequency, and bandwidth, and various elements of the wireless signal such as modulation method, error correction method, synchronization signal information, and scrambling seed. Each element of the wireless signal contains one or more of these elements.

[0036] As described above, database 115 stores information indicating the geographical location of Zone 300 to which mobile station 100 can belong, i.e., within the service area, information indicating the anchor point 200 used for positioning of mobile station 100 in each Zone 300, and information on communication parameters required for communication between mobile station 100 and anchor point 200 or for the determination of positioning signals from anchor point 200.

[0037] The positioning information acquisition unit 116 uses the communication parameters included in the anchor point information obtained from the database 115 to communicate with each anchor point 200 of the designated anchor point group determined by the anchor point determination unit 114, or measures the positioning signals from each anchor point 200 of the designated anchor point group, to obtain positioning information (step S105). It is envisioned that the positioning information is information representing the positional relationship between the anchor point 200 and the mobile station 100, such as distance, orientation, and power value, but this is not limited to this. The positioning information acquisition unit 116 outputs the acquired positioning information to the position calculation unit 117.

[0038] The location calculation unit 117 calculates the accurate location of the mobile station 100 based on the location information obtained from the location information acquisition unit 116 and the location information of the anchor points 200 included in the anchor point information obtained from the database 115 (step S106). For example, if the location calculation unit 117 obtains the accurate distances to the three anchor points 200, it can determine the accurate location of the mobile station 100 on the plane through triangulation. While outputting the calculated location information of the mobile station 100 to the upper-level layer, application program, etc., the location calculation unit 117 saves it together with relevant information such as the positioning time to the trajectory storage unit 111.

[0039] The database 115 used in this embodiment will be described. As described above, when the installer of the positioning infrastructure and the user of the positioning application are the same entity, the positioning application can utilize information about the location and communication parameters of the anchor point 200. In order to effectively utilize this information, the user, who is both the installer of the positioning infrastructure and the user of the positioning application, pre-creates a database containing... Figure 4 The area information shown in the image and in Figure 5 The database 115 shows anchor point information. That is, the user measures the electromagnetic wave propagation status between each anchor point 200 and the mobile station 100 along the envisioned movement path of the mobile station 100, and selects anchor points 200 that (1) have a guaranteed line of sight, (2) have high receiving power, and (3) have a small number of multipaths. At this time, the user selects the minimum number of anchor points 200 required for positioning plus spare anchor points 200. This is because in actual use environments, communication channels may be interrupted due to temporary shielding. The same locations of the selected candidate anchor points 200 are grouped into Zone 300. In other words, all anchor points 200 belonging to the same Zone 300 should be used for positioning of the mobile station 100.

[0040] By storing the setting parameters of the wireless infrastructure, i.e., the positioning infrastructure, constituting the anchor point 200 in the database 115, the positioning system 101 can obtain the information required for positioning in a short time without sensing notification information. If the information that should be stored in the database 115 of the positioning system 101 is quasi-static, the information can be saved in advance, for example, written to memory. If the information that should be stored in the database 115 of the positioning system 101 is quasi-dynamic, the information can be obtained via communication lines, i.e., downloaded and saved, before the use of the mobile station 100 begins.

[0041] Next, the hardware structure of the positioning system 101 will be described. In the positioning system 101, the positioning control unit 110, the trajectory storage unit 111, the estimated position calculation unit 112, the area determination unit 113, the anchor point determination unit 114, the database 115, the positioning information acquisition unit 116, and the position calculation unit 117 are implemented by a processing circuit. The processing circuit can be a processor that executes a program stored in memory, or it can be dedicated hardware. The processing circuit is also called a control circuit.

[0042] Figure 6 This diagram illustrates a structural example of the processing circuit 90 in the case where the processing circuit of the positioning system 101 according to Embodiment 1 is implemented by a processor 91 and a memory 92. Figure 6 The processing circuit 90 shown is a control circuit, comprising a processor 91 and a memory 92. When the processing circuit 90 is composed of the processor 91 and the memory 92, the functions of the processing circuit 90 are implemented through software, firmware, or a combination of both. The software or firmware is described as a program and stored in the memory 92. In the processing circuit 90, the processor 91 executes the program stored in the memory 92 by reading it, thereby implementing the various functions. That is, the processing circuit 90 has a memory 92 for storing a program that enables the final execution of the processing of the positioning system 101. This program can also be described as a program for causing the positioning system 101 to perform the various functions implemented by the processing circuit 90. This program can be provided by a storage medium storing the program, or by other means such as a communication medium.

[0043] The above procedure can also be described as a procedure in which the positioning system 101 performs the following steps: Step 1, the estimated position calculation unit 112 calculates the estimated position of the mobile station 100; Step 2, the area determination unit 113 determines the Zone 300 to which the mobile station 100 belongs based on the estimated position of the mobile station 100 and the information stored in the database 115; Step 3, the anchor point determination unit 114 determines the anchor point 200 used by the mobile station 100 in the measurement of communication or positioning signals based on the Zone 300 to which the mobile station 100 belongs and the information stored in the database 115; Step 4, the positioning information acquisition unit 116 acquires positioning information indicating the positional relationship between the determined anchor point 200 and the mobile station 100 by communicating with the determined anchor point 200 or measuring the positioning signal from the determined anchor point 200; and Step 5, the position calculation unit 117 calculates the position of the mobile station 100 based on the positioning information and the information stored in the database 115.

[0044] Here, processor 91 is, for example, a CPU (Central Processing Unit), processing device, arithmetic device, microprocessor, microcomputer, or DSP (Digital Signal Processor). Additionally, memory 92 is, for example, non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable ROM), EEPROM (Electrically EPROM), magnetic disk, floppy disk, optical disk, compact disk, mini-disk, or DVD (Digital Versatile Disc).

[0045] Figure 7 This diagram illustrates an example of the processing circuit 93 in the case where the positioning system 101 according to Embodiment 1 is configured with processing circuitry using dedicated hardware. Figure 7 The processing circuit 93 shown is, for example, a single circuit, a composite circuit, a programmable processor, a parallel-programmable processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. The processing circuit may also be implemented partly by dedicated hardware and partly by software or firmware. In this way, the processing circuit can implement the aforementioned functions through dedicated hardware, software, firmware, or a combination thereof.

[0046] As described above, according to this embodiment, the positioning system 101 calculates the estimated location of the mobile station 100, uses the information stored in the database 115 to determine the Zone 300 to which the mobile station 100 belongs, determines the anchor point 200 used by the mobile station 100 for positioning, obtains positioning information, and calculates the location of the mobile station 100. Therefore, the positioning system 101 can locate the mobile station 100 with minimal communication, and can obtain positioning results with low latency while suppressing the consumption of wireless resources.

[0047] Implementation Method 2

[0048] In Embodiment 1, the mobile station 100 has a structure that includes a positioning system 101. In Embodiment 2, the case in which the positioning system is composed of a mobile station and a positioning network device installed on the ground will be described.

[0049] Figure 8This is a block diagram illustrating a structural example of the positioning system 102 according to Embodiment 2. The positioning system 102 includes a mobile station 103 and a positioning network device 104. The positioning system 102 is structured such that the positioning control of the mobile station 103 and the location calculation of the mobile station 103 are performed by the positioning network device 104. The positioning network device 104 is installed on the ground and is sometimes referred to as a local server. The mobile station 103 includes a communication unit 123, an estimated location calculation unit 124, and a positioning information acquisition unit 125. The positioning network device 104 includes a positioning control unit 110, an estimated location calculation instruction unit 120, an area determination unit 113, an anchor point determination unit 114, a database 115, a location calculation unit 121, and a communication unit 122. That is, in Embodiment 2, the communication unit 123, the estimated location calculation unit 124, and the positioning information acquisition unit 125 are mounted on the mobile station 103. The positioning control unit 110, the estimated position calculation instruction unit 120, the area determination unit 113, the anchor point determination unit 114, the database 115, the position calculation unit 121, and the communication unit 122 are mounted on the positioning network device 104. Figure 9 This is a flowchart illustrating the operation of the positioning system 102 according to Embodiment 2.

[0050] If the positioning control unit 110 receives a positioning request from the upper layer or the application, it instructs the estimated position calculation instruction unit 120 to perform estimated position calculation on the mobile station 103 (step S201).

[0051] The estimated position calculation instruction unit 120 communicates with the mobile station 103 via the communication unit 122, and sends the estimated position calculation instruction of the mobile station 103 to the estimated position calculation unit 124 via the communication unit 123 of the mobile station 103 (step S202).

[0052] The estimated location calculation unit 124 calculates the estimated location of the mobile station 103 using a certain method (step S203). The method for calculating the estimated location of the mobile station 103 in the estimated location calculation unit 124 is the same as the method for calculating the estimated location of the mobile station 100 performed by the estimated location calculation unit 112 in Embodiment 1. The estimated location calculation unit 124 transmits the calculated estimated location information to the area determination unit 113 of the positioning network device 104 via the communication unit 123 and the communication unit 122 of the positioning network device 104 (step S204).

[0053] The area determination unit 113 determines the Zone 300 to which the mobile station 103 belongs based on the estimated position information obtained from the estimated position calculation unit 124 of the mobile station 103 and the area information obtained from the database 115 (step S205). The area determination unit 113 outputs the information of the Zone 300 to which the mobile station 103 belongs to the anchor point determination unit 114.

[0054] Based on information about the Zone 300 to which the mobile station 103 belongs, obtained from the Zone Determination Unit 113, and area information obtained from the database 115, the anchor point determination unit 114 determines the anchor point 200 to be used by the mobile station 103 in measuring communication or positioning signals (step S206). The anchor point determination unit 114 outputs the identification information of the determined anchor point 200 to the location calculation unit 121. In addition, the anchor point determination unit 114 transmits the identification information of the determined anchor point 200 and the communication parameters with each anchor point 200 to the positioning information acquisition unit 125 of the mobile station 103 via the communication unit 122 and the communication unit 123 of the mobile station 103 (step S207).

[0055] The positioning information acquisition unit 125 acquires positioning information (step S208) by communicating with each anchor point 200 of a designated anchor point group determined by the anchor point determination unit 114, based on information obtained from the anchor point determination unit 114 of the positioning network device 104, or by measuring the positioning signals from each anchor point 200 of the designated anchor point group. The positioning information is envisioned to be information indicating the positional relationship between the anchor point 200 and the mobile station 103, such as distance, orientation, and power value, but is not limited to this. The communication method with each anchor point 200 or the method for measuring the positioning signals from each anchor point 200 in the positioning information acquisition unit 125 is the same as the communication method with each anchor point 200 or the method for measuring the positioning signals from each anchor point 200 performed by the positioning information acquisition unit 116 in Embodiment 1. The location information acquisition unit 125 sends the acquired location information to the location calculation unit 121 of the location network device 104 via the communication unit 123 and the communication unit 122 of the location network device 104 (step S209).

[0056] The location calculation unit 121 calculates the accurate location of the mobile station 103 based on the location information obtained from the location information acquisition unit 125 of the mobile station 103 and the location information of the anchor point 200 included in the anchor point information obtained from the database 115 (step S210). The location calculation unit 121 outputs the calculated location information of the mobile station 103 to the upper-level layer, application program, and other upper-level layers.

[0057] Next, the hardware structure of the mobile station 103 and the positioning network device 104 constituting the positioning system 102 will be described. In the mobile station 103, the communication unit 123 is a communication device. In the mobile station 103, the estimated position calculation unit 124 and the positioning information acquisition unit 125 are implemented by a processing circuit. In the positioning network device 104, the communication unit 122 is a communication device. In the positioning network device 104, the positioning control unit 110, the estimated position calculation instruction unit 120, the area determination unit 113, the anchor point determination unit 114, the database 115, and the position calculation unit 121 are implemented by a processing circuit. The processing circuits of the mobile station 103 and the positioning network device 104 are the same as those of the positioning system 101 in Embodiment 1; they can be a processor and a memory that execute programs stored in a memory, or they can be dedicated hardware.

[0058] As described above, according to this embodiment, the positioning network device 104 of the positioning system 102 has a database 115, and its structure is a reduction of the functions of the mobile station 103 compared to the mobile station 100 of Embodiment 1. Therefore, by achieving the same effect as Embodiment 1 while reducing the functions of a large number of mobile stations 103, the positioning system 102 can simplify its structure.

[0059] Implementation Method 3

[0060] The positioning system 101 of Embodiment 1 and the positioning system 102 of Embodiment 2 obtain information about the anchor point 200 for communication from the database 115 based on the estimated location of the mobile station, thus enabling efficient positioning. On the other hand, a mismatch between the information stored in the database 115 and the actual communication status becomes a problem. In Embodiment 3, the situation where a mismatch occurs between the information stored in the database 115 and the actual communication status will be described. Embodiment 3 can be applied to either the positioning system 101 of Embodiment 1 or the positioning system 102 of Embodiment 2, but here, as an example, the positioning system 101 of Embodiment 1 will be described.

[0061] Figure 10 This is a flowchart illustrating the actions taken in the positioning system 101 according to Embodiment 3 when a mismatch occurs between the database 115 and the actual communication state.

[0062] When the position estimation calculation unit 112 receives an instruction from the positioning control unit 110 to calculate the estimated position of the mobile station 100, it attempts to perform the estimated position calculation. However, sometimes the calculation fails due to various reasons such as the absence of a previously calculated position, the lack of an initial position, or the failure to find a magnetic marker. If the position estimation calculation unit 112 successfully performs the estimated position calculation (step S301: Yes), the positioning system 101 proceeds to step S302. If the position estimation calculation performed by the position estimation calculation unit 112 fails (step S301: No), the positioning system 101 proceeds to step S306.

[0063] When the area determination unit 113 obtains the estimated location information of the mobile station 100 from the estimated location calculation unit 112, it attempts to determine the Zone 300 to which the mobile station 100 belongs. However, sometimes the area determination fails because the coordinates equivalent to the estimated location information are outside the range of the database 115. If the area determination unit 113 successfully performs an area determination based on the database 115 (step S302: Yes), the positioning system 101 proceeds to step S303. If the area determination performed by the area determination unit 113 based on the database 115 fails (step S302: No), the positioning system 101 proceeds to step S306.

[0064] The positioning system 101 determines the anchor point 200 that should be used for positioning by the anchor point determination unit 114 (step S303) and proceeds to step S304.

[0065] The positioning information acquisition unit 116 attempts to communicate with the anchor point 200 or measure the positioning signal from the anchor point 200 in order to obtain positioning information. However, sometimes communication or positioning signal measurement fails due to equipment failure, shielding, or other reasons. The database 115 sets up a certain degree of redundancy for the anchor points 200 that should be used. However, if the number of anchor points 200 capable of communication or positioning signal measurement falls below the number of anchor points 200 required for the positioning of the mobile station 100, the positioning information acquisition unit 116 cannot perform positioning of the mobile station 100. In such cases, the positioning information acquisition unit 116 determines that communication with the anchor point 200 or measurement of the positioning signal from the anchor point 200 has failed. When the positioning system 101 successfully performs communication with the anchor point 200 or measurement of the positioning signal from the anchor point 200, it determines that positioning information acquisition has been successfully performed (step S304: Yes) and proceeds to step S305. If the positioning system 101 fails to communicate with the anchor point 200 or fails to measure the positioning signal from the anchor point 200, it determines that the acquisition of positioning information has failed (step S304: No) and proceeds to step S306.

[0066] The location calculation unit 117 attempts to calculate the location of the mobile station 100 using location information, but sometimes the location calculation fails because the mobile station 100's location deviates from the predetermined movement route or is located in a position that cannot be compared with the information in the database 115. If the location calculation unit 117 successfully calculates the location of the mobile station 100 (step S305: Yes), the positioning system 101 outputs the calculated location information of the mobile station 100 to the upper-level layer, application, etc., and ends the operation. If the location calculation unit 117 fails to calculate the location of the mobile station 100 (step S305: No), the positioning system 101 proceeds to step S306.

[0067] If the positioning of the mobile station 100 based on the database 115 fails for some reason, the positioning system 101 switches to an autonomous mode that performs positioning of the mobile station 100 independently without using the database 115. The failure of the positioning of the mobile station 100 based on the database 115 refers to the failure of the estimated position calculation of the mobile station 100 performed by the estimated position calculation unit 112 (step S301: No), the failure of the determination of the Zone 300 to which the mobile station 100 belongs performed by the area determination unit 113 (step S302: No), the failure of the acquisition of positioning information performed by the positioning information acquisition unit 116 (step S304: No), or the failure of the position calculation of the mobile station 100 performed by the position calculation unit 117 (step S305: No).

[0068] First, to confirm the existence of the positioning infrastructure, i.e., anchor point 200, the positioning system 101 observes the notification signals reported from the surrounding anchor points 200 (step S306). The positioning system 101 observes the notification signals and obtains information such as received power and propagation status. The propagation status includes line-of-sight conditions, multipath status, etc. At this time, the positioning system 101 also obtains various elements of the wireless signal from the notification information contained in the notification signals. The positioning system 101 extracts candidate anchor points with priority based on anchor points 200 with high received power and those that can ensure line-of-sight conditions (step S307). The positioning system 101 lists the extracted anchor points 200. At this time, the positioning system 101 excludes the anchor points 200 that failed to communicate in step S304. The positioning system 101 determines the anchor point 200 that should be used for positioning using the anchor point determination unit 114 (step S303) and proceeds to step S304.

[0069] Furthermore, when the above-described actions are applied to Embodiment 2, if the positioning of the mobile station 103 based on the database 115 fails for some reason, the positioning network device 104 switches to an autonomous mode that performs positioning of the mobile station 103 autonomously without using the database 115. The failure of the positioning of the mobile station 103 based on the database 115 to perform positioning for some reason refers to the failure of the estimated location calculation of the mobile station 103 by the estimated location calculation unit 124 of the mobile station 103 (step S301: No), the failure of the determination of the Zone 300 to which the mobile station 103 belongs by the area determination unit 113 (step S302: No), the failure of the acquisition of positioning information by the positioning information acquisition unit 125 of the mobile station 103 (step S304: No), or the failure of the location calculation of the mobile station 103 by the location calculation unit 121 (step S305: No).

[0070] First, to confirm the existence of the positioning infrastructure, i.e., the anchor point 200, the positioning network device 104 observes the notification signals transmitted from the surrounding anchor points 200 via the mobile station 103 (step S306). The positioning network device 104 observes the notification signals and obtains information such as received power and propagation status. At this time, the positioning network device 104 also obtains various elements of the wireless signal from the notification information contained in the notification signals. The positioning network device 104 prioritizes anchor points 200 with high received power and those that can ensure line-of-sight conditions (step S307). The positioning network device 104 lists the extracted anchor points 200. At this time, the positioning network device 104 excludes the anchor points 200 that failed to communicate in step S304. The positioning network device 104 determines the anchor point 200 that should be used for positioning using the anchor point determination unit 114 (step S303) and proceeds to step S304.

[0071] As described above, according to this embodiment, when a mismatch occurs between the information stored in the database 115 and the actual communication status, the positioning system 101 switches to an autonomous mode that performs positioning of the mobile station 100 independently without using the database 115. Therefore, the positioning system 101 can avoid situations where positioning of the mobile station 100 is impossible. Similarly, when a mismatch occurs between the information stored in the database 115 and the actual communication status, the positioning system 102 switches to an autonomous mode that performs positioning of the mobile station 103 independently without using the database 115. Therefore, the positioning system 102 can avoid situations where positioning of the mobile station 103 is impossible.

[0072] The structure shown in the above embodiments is an example that can be combined with other known technologies, and the embodiments can be combined with each other. Parts of the structure can also be omitted or modified without departing from the spirit of the subject.

[0073] Explanation of the label

[0074] 1. Wireless communication system; 100, 103. Mobile station; 101, 102. Positioning system; 104. Positioning network device; 110. Positioning control unit; 111. Track storage unit; 112, 124. Estimated position calculation unit; 113. Area determination unit; 114. Anchor point determination unit; 115. Database; 116, 125. Positioning information acquisition unit; 117, 121. Position calculation unit; 120. Estimated position calculation instruction unit; 122, 123. Communication unit; 200-1 to 200-6. Anchor points; 300-A to 300-H.

Claims

1. A positioning system, characterized in that, have: The estimated location calculation unit calculates the estimated location of the mobile station; The database stores information representing the geographical location of the area within the service range of the mobile station, information representing the anchor points used for positioning of the mobile station in each area, and information on the communication parameters required for the mobile station to communicate with the anchor points or to measure positioning signals from the anchor points. The region determination unit determines the region to which the mobile station belongs based on the estimated location of the mobile station and the information stored in the database; The anchor point determination unit determines the anchor point used by the mobile station in measuring communication or positioning signals based on the area to which the mobile station belongs and the information stored in the database. The positioning information acquisition unit acquires positioning information representing the positional relationship between the determined anchor point and the mobile station by communicating with the determined anchor point or measuring the positioning signal from the determined anchor point; as well as The location calculation unit calculates the location of the mobile station based on the location information and the information stored in the database.

2. The positioning system according to claim 1, characterized in that, The database stores this information in advance.

3. The positioning system according to claim 1, characterized in that, The database stores the information via a communication line before the use of the mobile station begins.

4. The positioning system according to any one of claims 1 to 3, characterized in that, The communication parameters stored in the database include: The information used to identify the anchor point includes the cell global identifier. The various elements of a wireless signal include center frequency, bandwidth, subcarrier bandwidth, cyclic prefix length, and synchronization signal information based on the 3rd Generation Partnership Project (GPP) standard TS38.211, i.e., N. ID cell =3N ID (1) +N ID (2) The port number, scrambling IDs for demodulation reference signal category generation, positioning reference signal resource allocation information, downlink positioning reference signal sequence ID, and one or more of the following information recorded in TS37.355-g20: DL-PRS-ID-Info, NR-DL-PRS-AssistanceData, NR-DL-PRS-BeamInfo, NR-DL-PRS-Info, NR-DL-PRS-ResourceID, NR-DL-PRS-ResourceSetID, and NR-SelectedDL-PRS-IndexList.

5. The positioning system according to any one of claims 1 to 3, characterized in that, The communication parameters stored in the database include: The information used to identify the anchor point includes the inherent information of the anchor point. The various elements of a wireless signal include one or more of the following: channel number, scrambling timestamp sequence message structure information, pulse repetition frequency pattern, preamble, frame header delimiter field structure information, physical header parameters, and space-time stream field structure information.

6. The positioning system according to any one of claims 1 to 3, characterized in that, If the estimated location calculation of the mobile station fails, or if the determination of the area to which the mobile station belongs fails by the area determination unit, or if the acquisition of the location information fails by the location information acquisition unit, or if the location calculation of the mobile station fails by the location calculation unit, The system switches to an autonomous mode that does not use the database, observes the notification signals of the anchor points around the mobile station, obtains various elements such as received power, propagation status, and wireless signal, and determines the anchor point to be used for positioning.

7. The positioning system according to any one of claims 1 to 3, characterized in that, The estimated location calculation unit, the database, the area determination unit, the anchor point determination unit, the positioning information acquisition unit, and the location calculation unit are mounted on the mobile station.

8. The positioning system according to any one of claims 1 to 3, characterized in that, The database, the region determination unit, the anchor point determination unit, and the location calculation unit are mounted on a positioning network device installed on the ground. The estimated location calculation unit and the positioning information acquisition unit are mounted on the mobile station.

9. A positioning network device, which, together with a mobile station, constitutes a positioning system for locating the position of the mobile station. Its features are, have: An estimated position calculation instruction unit instructs the mobile station to calculate its estimated position. The database stores information representing the geographical location of the area within the service range of the mobile station, information representing the anchor points used for positioning of the mobile station in each area, and information on the communication parameters required for the mobile station to communicate with the anchor points or to measure positioning signals from the anchor points. The region determination unit determines the region to which the mobile station belongs based on the estimated location of the mobile station calculated by the mobile station and the information stored in the database; The anchor point determination unit determines the anchor point used by the mobile station in measuring communication or positioning signals based on the area to which the mobile station belongs and the information stored in the database. as well as The location calculation unit calculates the location of the mobile station based on the positioning information of the anchor point and the mobile station's positional relationship determined by the representation obtained by the mobile station, and the information stored in the database.

10. The positioning network device according to claim 9, characterized in that, The database stores this information in advance.

11. The positioning network device according to claim 9, characterized in that, The database stores the information via a communication line before the use of the mobile station begins.

12. The positioning network device according to any one of claims 9 to 11, characterized in that, The communication parameters stored in the database include: The information used to identify the anchor point includes the cell global identifier. The various elements of a wireless signal include center frequency, bandwidth, subcarrier bandwidth, cyclic prefix length, and synchronization signal information based on the 3rd Generation Partnership Project (GPP) standard TS38.211, i.e., N. ID cell =3N ID (1) +N ID (2) The port number, scrambling IDs for demodulation reference signal category generation, positioning reference signal resource allocation information, downlink positioning reference signal sequence ID, and one or more of the following information recorded in TS37.355-g20: DL-PRS-ID-Info, NR-DL-PRS-AssistanceData, NR-DL-PRS-BeamInfo, NR-DL-PRS-Info, NR-DL-PRS-ResourceID, NR-DL-PRS-ResourceSetID, and NR-SelectedDL-PRS-IndexList.

13. The positioning network device according to any one of claims 9 to 11, characterized in that, The communication parameters stored in the database include: The information used to identify the anchor point includes the inherent information of the anchor point. The various elements of a wireless signal include one or more of the following: channel number, scrambling timestamp sequence message structure information, pulse repetition frequency pattern, preamble, frame header delimiter field structure information, physical header parameters, and space-time stream field structure information.

14. The positioning network device according to any one of claims 9 to 11, characterized in that, In the event that the calculation of the estimated location of the mobile station performed by the mobile station fails, or the determination of the area to which the mobile station belongs by the area determination unit fails, or the acquisition of the positioning information performed by the mobile station fails, or the calculation of the location of the mobile station performed by the location calculation unit fails, The system switches to an autonomous mode that does not use the database, observes the notification signals of the anchor points around the mobile station, obtains various elements such as received power, propagation status, and wireless signal, and determines the anchor point to be used for positioning.

15. A control circuit for controlling a positioning system, characterized in that, The positioning system has a database that stores information representing the geographical locations of the mobile station within its service area, information representing the anchor points used for positioning the mobile station in each area, and information on the communication parameters required for the mobile station to communicate with the anchor points or to measure positioning signals from the anchor points. The control circuit causes the positioning system to perform the following processes: Calculate the estimated location of the mobile station. The region to which the mobile station belongs is determined based on the estimated location of the mobile station and the information stored in the database. The anchor point used by the mobile station in measuring communication or positioning signals is determined based on the area to which the mobile station belongs and the information stored in the database. Positioning information representing the positional relationship between the determined anchor point and the mobile station is obtained through communication with the determined anchor point or by measuring the positioning signal from the determined anchor point. The location of the mobile station is calculated based on the location information and the information stored in the database.

16. A computer-readable storage medium storing a program for controlling a positioning system, characterized in that, The positioning system has a database that stores information representing the geographical locations of the mobile station within its service area, information representing the anchor points used for positioning the mobile station in each area, and information on the communication parameters required for the mobile station to communicate with the anchor points or to measure positioning signals from the anchor points. The program causes the positioning system to perform the following processes: Calculate the estimated location of the mobile station. The region to which the mobile station belongs is determined based on the estimated location of the mobile station and the information stored in the database. The anchor point used by the mobile station in measuring communication or positioning signals is determined based on the area to which the mobile station belongs and the information stored in the database. Positioning information representing the positional relationship between the determined anchor point and the mobile station is obtained through communication with the determined anchor point or by measuring the positioning signal from the determined anchor point. The location of the mobile station is calculated based on the location information and the information stored in the database.

17. A positioning method, which is a positioning method for a positioning system, characterized in that, The positioning system has a database that stores information representing the geographical locations of the mobile station within its service area, information representing the anchor points used for positioning the mobile station in each area, and information on the communication parameters required for the mobile station to communicate with the anchor points or to measure positioning signals from the anchor points. This positioning method includes the following steps: Step 1: The estimated location calculation unit calculates the estimated location of the mobile station; In the second step, the area determination unit determines the area to which the mobile station belongs based on the estimated location of the mobile station and the information stored in the database. Step 3: The anchor point determination unit determines the anchor point used by the mobile station in measuring communication or positioning signals based on the area to which the mobile station belongs and the information stored in the database. Step 4: The positioning information acquisition unit acquires positioning information representing the positional relationship between the determined anchor point and the mobile station through communication with the determined anchor point or by measuring the positioning signal from the determined anchor point; and Step 5: The location calculation unit calculates the location of the mobile station based on the positioning information and the information stored in the database.

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