Underground coal mine TOF cross-region roaming positioning method

Abstract

The invention relates to a coal mine underground TOF cross-region roaming positioning method, and belongs to the field of wireless communication positioning. According to the method, grouping management is carried out on the card readers through a central station positioning engine, an accurate positioning area distribution map is generated in combination with a coal mine underground GIS map, and unified management is facilitated. The identification card and a plurality of card readers near the positioning area are positioned at the same time, so that roaming undisturbed switching is realized, and continuous, accurate, efficient and reliable positioning service is provided. The last frame of TOF ranging is used as the network access request frame of the same group of card readers, so that the TOF network access process is optimized, the ranging efficiency is improved, and the system concurrency is increased. A positioning area is divided for each card reader, cards are identified quickly and accurately, distance measurement interference between adjacent card readers is reduced, and the problem of cross-area positioning jump is solved. The method is suitable for a coal mine underground personnel positioning system, positioning precision and reliability can be improved, and underground operation safety is guaranteed.

Description

Technical Field

[0001] The invention belongs to the field of wireless communication positioning and relates to a TOF cross-regional roaming positioning method in underground coal mines. Background Art

[0002] The underground environment of coal mines is complex, with multiple potential interference sources such as gas, coal dust, and metal, which poses a severe challenge to the stability and accuracy of personnel positioning systems. Existing personnel positioning systems in coal mines mainly rely on one-dimensional positioning technology, which implements basic monitoring of personnel positions by deploying card readers at key locations and requiring personnel going down to the mine to wear identification cards. However, the positioning accuracy and coverage of this method are limited, and it is difficult to meet the needs of the complex environment of coal mines.

[0003] In recent years, ultra-wideband (UWB) technology has been widely used in the field of personnel positioning in coal mines due to its advantages of high precision, low power consumption, and high speed. UWB technology can achieve centimeter-level positioning accuracy and has strong anti-interference ability, and can provide stable and reliable positioning services even in complex environments. However, the application of UWB technology in coal mines still faces some challenges:

[0004] Cross-region roaming problem: The underground area of ​​coal mines is vast, and a large number of card readers need to be deployed to achieve full coverage. Due to factors such as time synchronization errors and frequency offsets between base stations, when identification cards roam across regions, problems such as positioning accuracy fluctuations and positioning delays are prone to occur, affecting the safety and efficiency of underground operations.

[0005] Positioning coordinate jump problem: Due to signal interference between adjacent card readers, when the identification card moves from one reader coverage area to another reader coverage area, positioning coordinate jumps are likely to occur, resulting in inaccurate positioning information.

[0006] Therefore, there is an urgent need for a TOF positioning method that can effectively solve the problems of cross-regional roaming and positioning coordinate jumping in coal mines, so as to improve positioning accuracy and reliability and ensure the safety of underground operations. Summary of the invention

[0007] In view of this, the purpose of the present invention is to provide a TOF cross-regional roaming positioning method in coal mines. The positioning area is divided for each card reader through the central station positioning engine, and the card readers are grouped and managed. The card reader can serve multiple groups. In addition to measuring the distance with the card reader of the positioning area to which it belongs, the identification card will also measure the distance with other card readers in the group to which the positioning area reader belongs. When the identification card leaves the current positioning area and enters the adjacent positioning area, since the two adjacent positioning areas are in the same group, the identification card has already measured the distance with the card reader of the adjacent positioning area before entering the adjacent positioning area. Therefore, when the identification card enters the adjacent positioning area, the positioning information can be directly switched to the adjacent positioning area without having to re-enter the network to allocate the timing. The problems of cross-regional roaming difficulties and positioning coordinate jumps in coal mines are solved.

[0008] In order to achieve the above object, the present invention provides the following technical solutions:

[0009] A TOF cross-region roaming positioning method for underground coal mines, comprising:

[0010] Set up a ground central station;

[0011] Several positioning card readers are set up in the coal mine, and all areas covered by the several positioning card readers need to ensure that they cover all areas in the coal mine;

[0012] The location information of underground workers or equipment is obtained through a number of identification cards that can perform TOF ranging with positioning card readers;

[0013] The ground central station assigns a unique serial number D1, D2, ..., DN to each positioning card reader, and the precise working range of each positioning card reader is its own positioning area, which is marked as SD1, SD2, ..., SDN respectively;

[0014] The ground central station integrates two or more adjacent positioning card readers into a card reader group, and assigns unique group numbers Z1, Z2, ..., ZK to each of them, wherein for each card reader group Zk, the serial number Dn of each positioning card reader in the group is recorded respectively;

[0015] For each positioning card reader Dn, the group number Zk of all the card reader groups to which it belongs and the serial numbers of all the positioning card readers under the group number are recorded respectively.

[0016] Furthermore, when the identification card enters the positioning area SDn of a positioning card reader Dn, the identification card first initiates a network access request frame, which can be received by all positioning card readers within the propagation range. The positioning card reader Dm that first receives the network access request frame replies to the network access request frame and performs an initial ranging. It determines whether it is the network access request of the same identification card B based on the initial ranging result. If the initial ranging result indicates that the identification card B is within the positioning area SDm of the positioning card reader Dm, the identification card B is allowed to access the network from the positioning card reader Dm. If the initial ranging result indicates that the identification card B is not within the positioning area SDm of the positioning card reader Dm, the positioning card reader Dm disconnects from the identification card B, and the network access request of the identification card B is received by other positioning card readers.

[0017] Furthermore, after the identification card successfully joins the network, TOF distance measurement is performed with the positioning card reader, and the positioning card reader Dn corresponding to the positioning area SDn where the identification card is located transmits the location information of the identification card to the ground central station.

[0018] Furthermore, after each completion of the TOF ranging, the received ranging end frame is broadcasted back, and the ranging end frame includes the group number Zk to which the corresponding positioning reader Dn belongs, as well as the current timing and ranging timing of the positioning reader Dn.

[0019] Furthermore, after receiving the broadcast, the positioning card reader Dm determines whether to receive the frame based on the group number Zk attached to it. If the positioning card reader Dm belongs to the group number information Zk it returns, it receives the frame and sends a ranging request to the identification card B in a manner that staggers the ranging timing of the positioning card reader Dn. The measured distance is not returned to the central station. When the identification card B enters the positioning area SDm of the positioning card reader Dm, the measured position information is returned to the central station. If the positioning card reader Dm does not belong to the locator group whose returned group number is Zk, the information is ignored.

[0020] Furthermore, since the identification card performs network access ranging with multiple card readers, the identification card has multiple ranging timings. When the ranging time of any ranging timing arrives, the identification card will wake up from sleep and initiate a ranging request frame for ranging, thereby realizing the function of simultaneous ranging between the identification card and multiple card readers in the group.

[0021] The beneficial effects of the present invention are:

[0022] (1) The card readers are grouped and managed through the central station positioning engine. Combined with the underground coal mine GIS map, a precise positioning area distribution map of the underground coal mine can be generated, which facilitates the unified management of underground coal mine positioning terminals.

[0023] (2) The identification card is located simultaneously with multiple card readers near the positioning area. There is no need to switch networks and re-enter the network when roaming across regions, achieving undisturbed roaming switching and providing users with continuous, accurate, efficient and reliable positioning services.

[0024] (3) The last frame of TOF ranging, i.e., the ranging end frame, is used as the network access request frame for the same group of card readers, which optimizes the TOF network access process, improves the ranging efficiency, and increases the system concurrency.

[0025] (4) Dividing the positioning area for each card reader can quickly and accurately identify the card, reduce the ranging interference between adjacent card readers, and solve the problem of cross-area positioning jumps.

[0026] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0028] Figure 1 This is a schematic diagram of card reader group management;

[0029] Figure 2 This is a schematic diagram of distance measurement for identification card access to the network;

[0030] Figure 3 This is a schematic diagram of distance measurement for grouped card readers to access the network;

[0031] Figure 4 This is a schematic diagram of cross-region roaming;

[0032] Figure 5 This is a flow chart of cross-region roaming. DETAILED DESCRIPTION

[0033] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0034] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0035] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0036] A cross-regional roaming positioning method for underground coal mines, firstly, a ground central station is set up, and then several positioning card readers are set up in the coal mine. All areas covered by the several positioning card readers need to ensure that they cover all areas in the coal mine. Then, the location information of underground workers or equipment is obtained through several identification cards that can perform TOF ranging with the positioning card readers. Specifically,

[0037] Assume that there are N positioning readers distributed at various points underground according to their precise working ranges. The central station assigns a unique serial number D1, D2, ..., DN to each positioning reader. The precise working range of each positioning reader is its own positioning area, which is identified as SD1, SD2, ..., SDN respectively; the central station integrates two or more adjacent positioning readers into a reader group and assigns unique group numbers Z1, Z2, ..., ZK respectively, wherein for each reader group Zk, the serial number Dn of each positioning reader in the group is recorded respectively; for each positioning reader Dn, the group number Zk of all the reader groups to which it belongs and the serial numbers of all the positioning readers under the group number are recorded respectively.

[0038] Specifically, if Figure 1As shown, it is assumed that there are card readers D1, D2, and D3, and their positioning areas are SD1, SD2, and SD3, which are combined in pairs to form locator groups, namely Z1 and Z2; then the locator group Z1 includes the locating reader D1 and the locating reader D2, and the locator group Z2 includes the locating reader D2 and the locating reader D3; for the locating reader D1, it records its own serial number D1, the locator group number Z1 to which it belongs, and other locating readers D2 under the locator group number Z1; for the locating reader D2, it records its own serial number D2, the locator group numbers Z1 and Z2 to which it belongs, other locating readers D1 under the locator group number Z1, and other locating readers Z3 under the locator group number Z2; for the locating reader D3, it records its own serial number D3, the locator group number Z2 to which it belongs, and other locating readers D2 under the locator group number Z2.

[0039] Suppose there is an identification card B. When it enters the positioning area SDn of a positioning card reader Dn, the identification card first initiates a network access request frame. The network access request frame can be received by all positioning card readers within the transmission range. The positioning card reader Dm that first receives the network access request frame replies to the network access request frame and performs an initial ranging. According to the initial ranging result, it is determined whether it is the network access request of the same identification card B. If the initial ranging result indicates that the identification card B is within the positioning area SDm of the positioning card reader Dm, the identification card B is allowed to access the network from the positioning card reader Dm. If the initial ranging result indicates that the identification card B is not within the positioning area SDm of the positioning card reader Dm, the positioning card reader Dm disconnects from the identification card B, and the network access request of the identification card B is received by other positioning card readers.

[0040] When identification card B successfully joins the network, it performs TOF ranging with the positioning card reader, and the positioning card reader Dn corresponding to the positioning area SDn where identification card B is located transmits the location information of identification card B to the ground central station.

[0041] After each distance measurement is completed, the received distance measurement end frame is transmitted back in the form of broadcast. The transmitted distance measurement end frame includes the group number Zk to which the corresponding positioning card reader Dn belongs, as well as the current timing and distance measurement timing of the positioning card reader Dn. After receiving the broadcast, other positioning card readers Dm determine whether to receive the frame according to the group number Zk attached to it. Specifically, if the positioning card reader Dm belongs to the group number information Zk transmitted back, it receives the frame and sends a distance measurement request to the identification card B in a manner that staggers the distance measurement timing of the positioning card reader Dn, but the measured distance is not transmitted back to the central station. When the identification card B enters the positioning area SDm of the positioning card reader Dm, the measured position information is transmitted back to the central station; if the positioning card reader Dm does not belong to the positioning group with the group number Zk transmitted back, the information is ignored.

[0042] Since the identification card performs network distance measurement with multiple card readers, the identification card has multiple distance measurement sequences. When the distance measurement time of any distance measurement sequence arrives, the identification card will wake up from sleep and initiate a distance measurement request frame for distance measurement. In this way, the identification card can perform distance measurement with multiple card readers in the group at the same time.

[0043] Embodiment 1:

[0044] Assume that five positioning readers D1, D2, D3, D4, and D5 are deployed in the coal mine, and their positioning areas are SD1, SD2, SD3, SD4, and SD5 respectively. The central station divides D1, D2, and D3 into a reader group Z1, and divides D4 and D5 into another reader group Z2.

[0045] When identification card B enters the positioning area SD1, it first initiates a network access request to the card reader group Z1. Card reader D1 first receives the network access request and performs the initial distance measurement. Since the initial distance measurement result shows that identification card B is located in SD1, D1 agrees to allow identification card B to enter the network, performs TOF distance measurement, and transmits the measured location information to the central station.

[0046] At the same time, D1 sends the ranging end frame in the form of broadcast, which includes the Z1 group number, D1 current timing and ranging timing. After receiving the broadcast, card readers D2 and D3, because they belong to the same group Z1, receive the frame and send ranging requests to identification card B at the same time as D1's ranging timing. However, the distances measured by D2 and D3 are not transmitted back to the central station.

[0047] When the identification card B moves to the positioning area SD2, D2 transmits its measured location information back to the central station. Since the identification card B has been measured in the Z1 group, it does not need to re-enter the network, and roaming without interference is achieved.

[0048] Embodiment 2:

[0049] Assume that four positioning readers D1, D2, D3, and D4 are deployed in the coal mine, and their positioning areas are SD1, SD2, SD3, and SD4 respectively. The central station divides D1 and D2 into one reader group Z1, and divides D3 and D4 into another reader group Z2.

[0050] When identification card B enters the positioning area SD1, it first initiates a network access request to the card reader group Z1. Card reader D1 first receives the network access request and performs the initial distance measurement. Since the initial distance measurement result shows that identification card B is located in SD1, D1 agrees to allow identification card B to enter the network, performs TOF distance measurement, and transmits the measured location information to the central station.

[0051] At the same time, D1 sends the ranging end frame in the form of broadcast, which includes the Z1 group number, D1 current timing and ranging timing. After receiving the broadcast, the card reader D2 receives the frame because it belongs to the same group Z1, and sends a ranging request to the identification card B at the same time as D1's ranging timing. However, the distance measured by D2 is not transmitted back to the central station.

[0052] When the identification card B moves to the positioning area SD2, D2 transmits its measured location information back to the central station. Since the identification card B has been measured in the Z1 group, it does not need to re-enter the network, and roaming without interference is achieved.

[0053] When identification card B continues to move to positioning area SD3, D3 receives the ranging end frame sent by D2, but because D3 belongs to group Z2, it ignores the information. Identification card B initiates a network access request to reader group Z2. Card reader D3 first receives the network access request and performs the initial ranging. Since the initial ranging result shows that identification card B is located in SD3, D3 agrees to allow identification card B to enter the network, performs TOF ranging, and transmits the measured location information to the central station.

[0054] At the same time, D3 sends the ranging end frame in the form of broadcast, which includes the Z2 group number, D3 current timing and ranging timing. After receiving the broadcast, the card reader D4 receives the frame because it belongs to the same group Z2, and sends a ranging request to the identification card B at the same time as D3's ranging timing. However, the distance measured by D4 is not transmitted back to the central station.

[0055] When the identification card B moves to the positioning area SD4, D4 transmits its measured location information back to the central station. Since the identification card B has been measured in the Z2 group, it does not need to re-enter the network, and roaming without interference is achieved.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A TOF cross-regional roaming positioning method for underground coal mines, characterized by: include: Set up a ground central station; Several positioning card readers are set up in the coal mine, and all areas covered by the several positioning card readers need to ensure that they cover all areas in the coal mine; The location information of underground workers or equipment is obtained through a number of identification cards that can perform TOF ranging with positioning card readers; The ground central station assigns a unique serial number D1, D2, ..., DN to each positioning card reader, and the precise working range of each positioning card reader is its own positioning area, which is marked as SD1, SD2, ..., SDN respectively; The ground central station integrates two or more adjacent positioning card readers into a card reader group, and assigns unique group numbers Z1, Z2, ..., ZK to each of them, wherein for each card reader group Zk, the serial number Dn of each positioning card reader in the group is recorded respectively; For each positioning card reader Dn, the group number Zk of all the card reader groups to which it belongs and the serial numbers of all the positioning card readers under the group number are recorded respectively.

2. A TOF cross-regional roaming positioning method for underground coal mines according to claim 1, characterized in that: When the identification card enters the positioning area SDn of a positioning card reader Dn, the identification card first initiates a network access request frame, which can be received by all positioning card readers within the propagation range. The positioning card reader Dm that first receives the network access request frame replies to the network access request frame and performs initial ranging. It determines whether it is the network access request of the same identification card B based on the initial ranging result. If the initial ranging result indicates that the identification card B is within the positioning area SDm of the positioning card reader Dm, the identification card B is allowed to access the network from the positioning card reader Dm. If the initial ranging result indicates that the identification card B is not within the positioning area SDm of the positioning card reader Dm, the positioning card reader Dm disconnects from the identification card B, and the network access request of the identification card B is received by other positioning card readers.

3. A TOF cross-regional roaming positioning method for underground coal mines according to claim 1, characterized in that: After the identification card successfully enters the network, TOF distance measurement is performed with the positioning card reader, and the positioning card reader Dn corresponding to the positioning area SDn where the identification card is located transmits the location information of the identification card to the ground central station.

4. A TOF cross-regional roaming positioning method for underground coal mines according to claim 1, characterized in that: After each completion of the TOF ranging, the received ranging end frame is broadcasted back, and the ranging end frame includes the group number Zk to which the corresponding positioning reader Dn belongs, as well as the current timing and ranging timing of the positioning reader Dn.

5. A TOF cross-regional roaming positioning method for underground coal mines according to claim 1, characterized in that: After receiving the broadcast, the positioning card reader Dm determines whether to receive the frame based on the group number Zk attached to it. If the positioning card reader Dm belongs to the group number information Zk it returns, it receives the frame and sends a ranging request to the identification card B in a manner that staggers the ranging timing of the positioning card reader Dn. The measured distance is not returned to the central station. When the identification card B enters the positioning area SDm of the positioning card reader Dm, the measured position information is returned to the central station. If the positioning card reader Dm does not belong to the locator group whose returned group number is Zk, the information is ignored.

6. A coal mine underground TOF cross-region roaming positioning method according to claim 1, characterized in that: Since the identification card performs network access ranging with multiple card readers, the identification card has multiple ranging timings. When the ranging time of any ranging timing arrives, the identification card will wake up from sleep and initiate a ranging request frame for ranging, thereby realizing the function of simultaneous ranging between the identification card and multiple card readers in the group.

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