UWB-based accurate positioning system for underground coal mine

Abstract

The invention relates to the technical field of mine underground positioning, and discloses a UWB-based coal mine underground accurate positioning system, which comprises a UWB base station, a UWB label, a central processing unit and a data transmission network, and is characterized in that the UWB base station is installed on a monorail hoist and is used as a signal receiver, the UWB label is fixed on a wall or a ceiling of a roadway and is used as a signal transmitter, and the central processing unit is used as a signal receiver. The central processing unit is responsible for receiving data from the UWB tag, executing a PDOA algorithm and calculating the position of the monorail hoist, and the data transmission network is used for data exchange between the base station and the tag and between the tag and the central processing unit. The monorail hoist can be quickly positioned, and rescue action is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of underground mine positioning, and in particular to an underground coal mine precise positioning system based on UWB. Background Art

[0002] UWB's precise positioning system in coal mines is achieved by installing a UWB base station on a monorail crane and installing UWB tags at fixed positions at certain intervals on the track. The position of the tag in the coal mine tunnel is known. When the monorail crane is traveling on the track, the base station continuously measures the relative position with the tag, thereby calculating the position of the monorail crane in the tunnel.

[0003] Most of the existing underground positioning technologies have problems such as low positioning accuracy, poor real-time performance, easy interference from the complex underground environment, and complex positioning system composition. The existing underground UWB positioning system has the disadvantages of high installation cost, poor deployment flexibility, low positioning angle accuracy, and extremely high time synchronization requirements. Therefore, we propose a precise positioning system for underground coal mines based on UWB. Summary of the invention

[0004] The present invention mainly solves the technical problems existing in the above-mentioned prior art and provides a precise positioning system for underground coal mines based on UWB.

[0005] In order to achieve the above-mentioned objectives, the present invention adopts the following technical scheme: a precise positioning system for underground coal mines based on UWB, including a UWB base station, a UWB tag, a central processing unit and a data transmission network. The UWB base station is installed on a monorail crane as a signal receiver, and the UWB tag is fixed on the wall or ceiling of the tunnel as a signal transmitter. The central processing unit is responsible for receiving data from the UWB tag, executing the PDOA algorithm, and calculating the position of the monorail crane. The data transmission network is used for data exchange between the base station and the tag, and between the tag and the central processing unit.

[0006] Preferably, the UWB base station adopts a dual antenna configuration. Two or more antennas are usually configured on the UWB base station. The distance between these antennas should be less than half a wavelength (d<λ / 2) to avoid phase ambiguity. This ensures that the signal will not produce a phase difference of more than 180° when propagating between the two antennas. Phase difference measurement refers to when the UWB signal arrives at the base station from the tag, due to the different signal propagation paths, the time for the signal to arrive at the two antennas is slightly different, resulting in a phase difference. By measuring this phase difference, the direction of signal arrival can be determined. Using the measured phase difference and the known signal wavelength, the angular difference of signal arrival can be calculated. The formula usually involves trigonometric functions, such as tangent functions, to convert the phase difference into angle information. After obtaining the angle information of the signal arrival, combined with the position of the base station and the angular difference of the signal arrival, the coordinate position of the tag can be calculated using trigonometric principles. This usually requires at least two base stations to determine the two-dimensional coordinates, or three base stations to determine the three-dimensional coordinates.

[0007] Preferably, the central processing unit is composed of an arithmetic unit and a controller, wherein the function of the controller is to coordinate and control the instruction sequence of the execution program of each component of the computer, including fetching instructions, analyzing instructions and executing instructions, and the function of the arithmetic unit is to process data.

[0008] Preferably, the UWB base station and the UWB tag adopt the TDOA algorithm, which is the time difference between the target sending signal and the arrival of each observation station. The TDOA algorithm includes a target, a reference observation station and several observation stations. Assuming that the position vector of the i-th observation station is sio=[si,xo,si,yo,si,zo]T, 1≤i≤M, then all observation station vectors are combined to obtain the total observation station position vector so=[s1o,s2o,sMo]T, and the target position vector is defined as uo=[uxo,uyo,uzo]T. Without loss of generality, the first observation station is taken as the reference observation station. Therefore, the calculation method of TDOA can be obtained as follows: (1)τj1o=||uo-sjo||2c-||uo-s1o||2c, 2≤j≤M, τj1o represents represents the true value of the time difference between the target signal arriving at the jth observation station and the reference observation station, where c represents the signal propagation speed, which is usually known, so TDOA can be converted into arrival distance difference, (2)rj1o=rjo-r1o=||uo-sjo||2-||uo-s1o||2, 2≤j≤M after considering the observation noise, (3)rj1=rj1o+δrj1The observation values ​​of all observation stations are combined to obtain a vector form, (4)r=ro+nr=[r21o,r31o,...,rM1o]T+[δr21,δr31,δrM1]T where ro=[r21o,r31o,rM1o]T represents the true value observation vector, nr=[δr21,δr31,δrM1]T represents the observation noise vector, and the covariance matrix of nr is denoted as Qr.

[0009] Preferably, the arithmetic unit receives commands from the controller and executes corresponding actions to process and handle data. The arithmetic unit is the center of the computer for processing and handling data. It is mainly composed of an arithmetic logic unit, a temporary register, an accumulator register, a general register group, a program status register, a shifter, a counter, etc. The main function of the arithmetic logic unit is to perform logical and arithmetic operations. The temporary register is used to temporarily store data read from the main memory. The data cannot be stored in a general register, otherwise its original content will be destroyed. The temporary register is transparent to the application programmer. The accumulator register is a general register used to display and store the result information of the ALU operation and can be used as an input end for addition operation. The general register group such as AX, BX, CX, DX, SP, etc. is used to store The operands include source operands, destination operands, intermediate results, and various address information. SP is the stack pointer, which is used to indicate the pointer to the top of the stack. The program status word register: retains various status information established by the results of arithmetic and logic operation instructions or test instructions, such as overflow flag, sign flag, zero flag, carry flag, etc. These bits in PSW participate in and determine the formation of micro-operations. The shifter performs shift operations on operands or operation results. The counter controls the number of operation steps of multiplication and division operations. The controller is the command center of the entire system. Under the control of the controller, functional components such as the arithmetic unit, memory, and input and output devices form an organic whole, which directs the coordinated work of the entire machine according to the requirements of the instructions. The basic function of the controller is to execute instructions. The execution of each instruction is realized by a group of micro-operations issued by the controller.

[0010] Preferably, the controller has two types: hard-wired controller and microprogram controller. The controller is composed of a program counter, an instruction register, an instruction decoder, a memory address register, a memory data register, a timing system and a micro-operation signal generator. The program register is used to indicate the address of the next instruction stored in the main memory. The CPU fetches instructions from the main memory according to the address in the register. Therefore, the instructions in the program are usually executed sequentially, so the PC has an automatic addition function. The instruction register is used to save the instruction currently being executed. The instruction decoder only decodes the opcode field of the instruction and provides a specific operation signal to the controller. The memory address register is used to It stores the address of the main memory unit to be accessed. The memory data register is used to store the information read from the main memory or written to the main memory. The timing system is used to generate various timing signals, which are all obtained by clock division. The micro-operation signal generator generates various control signals required to control the entire computer system according to the content stored in the IR, the content of the PSW and the timing signal. Its structure has combinational logic and storage logic types. The working principle of the controller is to form the control signals used by the current computer components according to the instruction operation code, the execution steps of the instruction and the conditional signals. The hardware systems of the computer work together under the control of these control signals to produce the expected execution results.

[0011] Beneficial Effects

[0012] The present invention provides a precise positioning system for coal mines based on UWB, which has the following beneficial effects:

[0013] (1) The UWB-based precise positioning system in coal mines monitors the position of the monorail crane in real time for dispatching and management to avoid collision accidents. In an emergency, the monorail crane can be quickly located to facilitate rescue operations.

[0014] (2) The UWB-based precise positioning system in coal mines, UWB technology can provide precise time measurement, which enables it to achieve centimeter-level accuracy in positioning applications.

[0015] (3) The UWB-based precise positioning system in coal mines is not easily detected by accidental or intentional eavesdroppers because the energy of UWB signals is dispersed over a wide frequency band and has a low power density, thereby increasing the security of communications.

[0016] (4) The UWB-based precise positioning system in coal mines combines PDoA with UWB. The high bandwidth characteristics of UWB signals allow precise time and phase measurements, so PDoA positioning can achieve very high accuracy, usually at the centimeter level. The short pulse characteristics of UWB help to distinguish direct signals from reflected signals in environments with multipath interference, thereby improving positioning accuracy and reliability. PDoA positioning can be performed in real time and is suitable for positioning needs in dynamic environments, such as industrial automation, logistics management, indoor navigation and other scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived based on the provided drawings without paying any creative work.

[0018] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0019] Figure 1 is a flow chart of a base station of the present invention;

[0020] Figure 2 This is a label flow chart of the present invention. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only 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 ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] like Figure 1-Figure 2As shown, a precise positioning system based on UWB in coal mines includes a UWB base station, a UWB tag, a central processing unit and a data transmission network. The UWB base station is installed on a monorail crane as a signal receiver. The UWB tag is fixed on the wall or ceiling of the tunnel as a signal transmitter. The central processing unit is responsible for receiving data from the UWB tag, executing the PDOA algorithm, and calculating the position of the monorail crane. The data transmission network is used for data exchange between the base station and the tag, and between the tag and the central processing unit.

[0023] The UWB base station and UWB tag use the TDOA algorithm. The TDOA algorithm is the time difference between the target sending signal and arriving at each observation station. The TDOA algorithm consists of a target, a reference observation station and several observation stations. Assuming that the position vector of the i-th observation station is sio=[si,xo,si,yo,si,zo]T, 1≤i≤M, then all observation station vectors are combined to obtain the total observation station position vector so=[s1o,s2o,,sMo]T, and the target position vector is defined as uo=[uxo,uyo,uzo]T. Without loss of generality, the first observation station is taken as the reference observation station. Therefore, we can get The calculation method of TDOA is, (1) τj1o = ||uo-sjo||2c-||uo-s1o||2c, 2≤j≤M, τj1o represents the true value of the time difference between the target signal arriving at the jth observation station and the reference observation station, where c represents the signal propagation speed, which is usually known, so TDOA can be converted into arrival distance difference, (2) rj1o = rjo-r1o = ||uo-sjo||2-||uo-s1o||2, 2≤j≤M after considering the observation noise, (3) rj1 = rj1o + δrj1 The observation values ​​of all observation stations are combined to obtain the vector form, (4) r = ro + nr=[r21o,r31o,,rM1o]T+[δr21,δr31,δrM1]T where ro=[r21o,r31o,,rM1o]T represents the true value observation vector, nr=[δr21,δr31,δrM1]T represents the observation noise vector, and the covariance matrix of nr is recorded as Qr. The UWB base station adopts a dual-antenna configuration. Two or more antennas are usually configured on the UWB base station. The distance between these antennas should be less than half a wavelength (d<λ / 2) to avoid phase ambiguity. This ensures that the signal will not produce a phase difference of more than 180° when propagating between the two antennas. The phase difference measurement is It means that when the UWB signal reaches the base station from the tag, due to the different signal propagation paths, the time it takes for the signal to reach the two antennas is slightly different, resulting in a phase difference. By measuring this phase difference, the direction of signal arrival can be determined. Using the measured phase difference and the known signal wavelength, the angular difference of signal arrival can be calculated. The formula usually involves trigonometric functions, such as the tangent function, to convert the phase difference into angle information. After obtaining the angle information of signal arrival, combined with the position of the base station and the angular difference of signal arrival, the coordinate position of the tag can be calculated using trigonometric principles. This usually requires at least two base stations to determine the two-dimensional coordinates, or three base stations to determine the three-dimensional coordinates.

[0024] The central processing unit is composed of an arithmetic unit and a controller. The function of the controller is to coordinate and control the instruction sequence of each computer component to execute the program, including fetching instructions, analyzing instructions and executing instructions. The function of the arithmetic unit is to process data. The arithmetic unit receives commands from the controller and performs corresponding actions to process and handle data. The arithmetic unit is the center of the computer for processing and handling data. It is mainly composed of an arithmetic logic unit, a temporary register, an accumulator register, a general register group, a program status register, a shifter, a counter, etc. The main function of the arithmetic logic unit is to perform logical and arithmetic operations. The temporary register is used to temporarily store data read from the main memory. The data cannot be stored in the general register, otherwise it will be destroyed. Its original content, the temporary register is transparent to the application programmer. The accumulator register is a general register used to display and store the result information of ALU operation. It can be used as an input terminal for addition operation. The general register group such as AX, BX, CX, DX, SP, etc. is used to store operands including source operands, destination operands, intermediate results and various address information. SP is the stack pointer, which is used to indicate the pointer at the top of the stack. The program status word register: retains various status information established by the results of arithmetic logic operation instructions or test instructions, such as overflow flag, sign flag, zero flag, carry flag, etc. These bits in PSW participate in and determine the formation of micro-operations. The shifter performs shift operations on operands or operation results, counting The controller controls the number of operation steps of multiplication and division operations. The controller is the command center of the entire system. Under the control of the controller, functional components such as the arithmetic unit, memory, and input and output devices form an organic whole, commanding the coordinated work of the entire machine according to the requirements of the instructions. The basic function of the controller is to execute instructions. The execution of each instruction is realized by a group of micro-operations issued by the controller. The controller is of two types: hard-wired controller and microprogram controller. The controller consists of a program counter, instruction register, instruction decoder, memory address register, memory data register, timing system and micro-operation signal generator. The program register is used to indicate the address of the next instruction stored in the main memory. The CPU fetches instructions from the main memory according to the address in the register. Therefore, the instructions in the program are usually executed sequentially, so the PC has an automatic addition function. The instruction register is used to save the instruction currently being executed. The instruction decoder only decodes the opcode field of the instruction and provides a specific operation signal to the controller. The memory address register is used to store the address of the main memory unit to be accessed. The memory data register is used to store information read from the main memory or written to the main memory. The timing system is used to generate various timing signals, which are all uniformly obtained by clock division. The micro-operation signal generator generates various control signals required to control the entire computer system based on the content stored in the IR, the content of the PSW and the timing signal. Its structure has combinational logic and storage logic types. The working principle of the controller is,According to the instruction operation code, the execution steps of the instruction and the conditional signal, the control signals used by the current computer components are formed. Under the control of these control signals, the hardware systems of the computer work together to produce the expected execution results.

[0025] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which shall fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A precise positioning system for underground coal mines based on UWB, comprising a UWB base station, a UWB tag, a central processing unit and a data transmission network, characterized in that: The UWB base station is installed on the monorail crane as a signal receiver, and the UWB tag is fixed on the wall or ceiling of the lane as a signal transmitter. The central processing unit is responsible for receiving data from the UWB tag, executing the PDOA algorithm, and calculating the position of the monorail crane. The data transmission network is used for data exchange between the base station and the tag, and between the tag and the central processing unit.

2. The precise positioning system based on UWB in coal mines according to claim 1, characterized in that: The UWB base station adopts a dual-antenna configuration. Two or more antennas are usually configured on the UWB base station. The distance between these antennas should be less than half a wavelength (d<λ / 2) to avoid phase ambiguity. This ensures that the signal will not produce a phase difference of more than 180° when propagating between the two antennas. Phase difference measurement refers to when the UWB signal arrives at the base station from the tag, due to the different signal propagation paths, the time for the signal to arrive at the two antennas is slightly different, resulting in a phase difference. By measuring this phase difference, the direction of signal arrival can be determined. Using the measured phase difference and the known signal wavelength, the angular difference of signal arrival can be calculated. The formula usually involves trigonometric functions, such as tangent functions, to convert the phase difference into angle information. After obtaining the angle information of the signal arrival, combined with the position of the base station and the angular difference of the signal arrival, the coordinate position of the tag can be calculated using trigonometric principles. This usually requires at least two base stations to determine the two-dimensional coordinates, or three base stations to determine the three-dimensional coordinates.

3. The precise positioning system based on UWB in coal mines according to claim 2, characterized in that: The central processing unit is composed of an arithmetic unit and a controller, wherein the function of the controller is to coordinate and control the instruction sequence of the execution program of each component of the computer, including fetching instructions, analyzing instructions and executing instructions, and the function of the arithmetic unit is to process data.

4. The precise positioning system for underground coal mines based on UWB according to claim 3 is characterized by: The UWB base station and the UWB tag adopt the TDOA algorithm. The TDOA algorithm is the time difference between the target sending signal and arriving at each observation station. The TDOA algorithm includes a target, a reference observation station and several observation stations. Assuming that the position vector of the i-th observation station is sio = [si, xo, si, yo, si, zo] T, 1≤i≤M, then all observation station vectors are combined to obtain the total observation station position vector so = [s1o, s2o, sMo] T, and the target position vector is defined as uo = [uxo, uyo, uzo] T. Without loss of generality, the first observation station is used as the reference observation station. Therefore, the calculation method of TDOA can be obtained as follows: (1) τj1o = ||uo-sjo||2c-||uo-s1o||2c, 2≤j≤M, τj1o represents the target The true value of the time difference between the signal arriving at the jth observation station and the reference observation station, where c represents the signal propagation speed, is usually known, so TDOA can be converted into the arrival distance difference, (2)rj1o=rjo-r1o=||uo-sjo||2-||uo-s1o||2, 2≤j≤M after considering the observation noise, (3)rj1=rj1o+δrj1The observation values ​​of all observation stations are combined to obtain the vector form, (4)r=ro+nr=[r21o,r31o,...,rM1o]T+[δr21,δr31,δrM1]T where ro=[r21o,r31o,rM1o]T represents the true value observation vector, nr=[δr21,δr31,δrM1]T represents the observation noise vector, and the covariance matrix of nr is denoted as Qr.

5. The precise positioning system for underground coal mines based on UWB according to claim 4 is characterized in that: The arithmetic unit receives commands from the controller and executes corresponding actions to process and handle data. The arithmetic unit is the center of the computer for processing and handling data. It is mainly composed of an arithmetic logic unit, a temporary register, an accumulator register, a general register group, a program status register, a shifter, a counter, etc. The main function of the arithmetic logic unit is to perform logical and arithmetic operations. The temporary register is used to temporarily store data read from the main memory. The data cannot be stored in a general register, otherwise its original content will be destroyed. The temporary register is transparent to the application programmer. The accumulator register is a general register used to display and store the result information of the ALU operation and can be used as an input end for addition operations. General register groups such as AX, BX, CX, DX, SP, etc. are used to store operation The numbers include source operands, destination operands, intermediate results, and various address information. SP is the stack pointer, which is used to indicate the pointer to the top of the stack. Program status word register: retains various status information established by the results of arithmetic and logic operation instructions or test instructions, such as overflow flag, sign flag, zero flag, carry flag, etc. These bits in PSW participate in and determine the formation of micro-operations. The shifter performs shift operations on operands or operation results. The counter controls the number of operation steps of multiplication and division operations. The controller is the command center of the entire system. Under the control of the controller, functional components such as the arithmetic unit, memory, and input and output devices form an organic whole, which directs the coordinated work of the entire machine according to the requirements of the instructions. The basic function of the controller is to execute instructions. The execution of each instruction is realized by a group of micro-operations issued by the controller.

6. The precise positioning system for underground coal mines based on UWB according to claim 5, characterized in that: The controller is of two types: hard-wired controller and microprogram controller. The controller is composed of a program counter, an instruction register, an instruction decoder, a memory address register, a memory data register, a timing system and a micro-operation signal generator. The register is used to indicate the address of the next instruction in the main memory. The CPU fetches the instruction from the main memory according to the address in the register. Therefore, the instructions in the program are usually executed sequentially, so the PC has an automatic addition function. The instruction register is used to save the instruction currently being executed. The instruction decoder only decodes the opcode field of the instruction and provides a specific operation signal to the controller. The memory address register is used to store the address of the main memory unit to be accessed. The memory data register is used to store the information read from the main memory or written to the main memory. The timing system is used to generate various timing signals, which are all uniformly obtained by clock division. The micro-operation signal generator generates various control signals required to control the entire computer system according to the content stored in the IR, the content of the PSW and the timing signal. Its structure has combinational logic and storage logic types. The working principle of the controller is to form the control signals used by the current computer components according to the instruction opcode, the execution steps of the instruction and the conditional signal. The hardware systems of the computer work together under the control of these control signals to produce the expected execution results.

Images