CN107071896A - One kind realizes colliery winding roadway object localization method using non line of sight signal - Google Patents
One kind realizes colliery winding roadway object localization method using non line of sight signal Download PDFInfo
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- CN107071896A CN107071896A CN201710206660.9A CN201710206660A CN107071896A CN 107071896 A CN107071896 A CN 107071896A CN 201710206660 A CN201710206660 A CN 201710206660A CN 107071896 A CN107071896 A CN 107071896A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W64/00—Locating users or terminals or network equipment for network management purposes, e.g. mobility management
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
- G01S5/02—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
- G01S5/0294—Trajectory determination or predictive filtering, e.g. target tracking or Kalman filtering
Abstract
Existing underground coal mine localization method is proposed for linear pattern tunnel mostly, and actual tunnel is often bending, and causing the application of existing localization method has certain limitation.For this problem, the invention provides one kind colliery winding roadway object localization method is realized using non line of sight signal, method takes full advantage of the positional information in tunnel, first the NLOS distance measurement values of winding roadway reconstruct for the first time to obtain the estimate of mobile target and corresponding base station air line distance；Secondly, the solution point of observational equation is projected to by lane space by second of reconstruct and obtains the higher subpoint of precision；Finally, design Kalman filter further optimizes the positioning precision of subpoint, so as to realize the positioning under more general curving tunnel.The present invention has effectively excavated NLOS ranging informations, it is adaptable to increasingly complex Minepit environment, and the exploitation for the quick effectively emergency rescue system in colliery provides reliable localization method with application.
Description
Technical field
Pinpoint method is carried out in underground coal mine the present invention relates to one kind, particular by unified non line of sight and sighting distance
Signal scene, the distance measure of mobile node and 2 fixed base stations can be obtained simultaneously, so as to realize the essence in winding roadway
It is determined that position.Belong to radio-location technology field, it is adaptable to the exploitation of underground coal mine Precise Position System and search and rescue system.
Background technology
The development of wireless location technology cause with more high position precision based on arrival time (Time of Arrival,
TOA localization method), is increasingly becoming the mainstream technology of mine personnel positioning system.Due to underground narrow space, electromagnetic environment is disliked
Bad, multipath effect is serious, causes arrival time for measuring by the influence of non line of sight (Non Line of Sight, NLOS) signal,
Therefore restraining NLOS error is optimization mine personnel positioning system positioning precision key issue to be solved.It is nearly all at present
Influence of the ripe locating and tracking algorithm as much as possible by NLOS signals to positioning is minimized.However, space of mine is narrow and small,
Eclipse phenomena is Great possibility, and actual tunnel is often bending, and NLOS signals are abandoned completely to realizing underground location
It is unfavorable.Therefore, excavate the useful information that is contained of NLOS signals and rationally utilized, under Minepit environment unified NLOS with
LOS scenes, more generally curving tunnel is applied to by localization method, undoubtedly to coal mine down-hole searching system, alignment system
Exploitation it is significant.
The content of the invention
In order to more effectively suppress influence of the underground coal mine NLOS signals to positioning precision and can fully excavate NLOS signals
Information realizes that colliery winding roadway target is determined the invention provides one kind to realize the positioning of winding roadway using non line of sight signal
Position method.Method considers actual mine laneway and non-fully linear pattern, and downhole positioning system is in the case of winding roadway, gesture
There must be NLOS phenomenons between mobile node and locating base station, therefore, the resolving ideas of method is that NLOS and LOS signals is unified
Processing, under abundant restraining NLOS error condition, ensures the positioning precision under winding roadway.
To achieve the above object, the technical scheme is that：One kind realizes colliery winding roadway using non line of sight signal
Object localization method, connected respectively by one section of circular curve type tunnel part and at its two ends two sections of described colliery winding roadway
Straight line tunnel is constituted, and using 2 station ranging plane positionings, 2 locating base station non line of sight placements are respectively placed in two sections of straight line tunnels area
Domain, tunnel length therebetween is less than the ultimate range that used ranging radio can be propagated in the tunnel；With two
The line of base station is x-axis, and tunnel cross direction is that y-axis sets up positioning plane coordinate system；Mobile target and base are obtained by TOA rangings
Pseudorange between standing, the i.e. distance value with measurement error；Described non line of sight signal refers to mobile node and one of those
Base station is in pseudorange measured during non line of sight state, and its pseudorange measured under sighting distance state with another base station is jointly shifting
Positioning of the moving-target in winding roadway provides ranging information.
Described utilization non line of sight signal realizes colliery winding roadway object localization method, specifically includes following steps：
(1) 5 index points are set in the winding roadway of positioning is interval and the tunnel length Ls between two base stations is determined；5
Individual index point is specifically located at the following location of winding roadway：2 base stations present position, the end positions and arc section of arc section
Point midway；
(2) pseudorange for obtaining mobile target rP to 2 base station is measured by TOA；
(3) non line of sight pseudorange is reconstructed, to obtain the mobile target rP under non line of sight state and the straight line puppet of base station
Away from；
(4) foundation measurement equation is fastened in the elements of a fix：I=1,2；Wherein, diTo move
Moving-target and the straight line pseudorange of i-th of base station, (xi,yi) for the position coordinates of i-th locating base station, (x, y) is mobile target rP
Position coordinates；Equation is measured using Taylor series solution by iterative method, the position coordinates mP (x, y) of solution point is obtained；
(5) smart reconstruct is carried out to the position mP (x, y) of solution point, obtains the observation station R2 (x, y) after essence reconstruct；
(6) Kalman filter is designed, observation station R2 (x, y) coordinate is defeated as the observation of Kalman filter
Enter, the output valve after Kalman filter is filtered for observation point coordinates is mobile target estimating in winding roadway actual value
Meter.
In the step (3), non line of sight pseudorange is reconstructed and comprised the following steps：
(1) by Δ ε=L1+d2-Ls, pseudorange biases the interval Δ ε, wherein L1 for obtaining mobile target rP two ends represent NLOS
The pseudorange value of one end, d2 represents the pseudorange value of LOS one end；
(2) index point set by simultaneous, obtains deviation interval Δ ε point midway R1；
(3) R1 and NLOS one end base station distance d1 are obtained, and is used as using d1 L1 reconstruction value.
In the step (5), position mP (x, y) the progress essence reconstruct to solution point comprises the following steps：
(1) index point set by simultaneous, determines the line segment where solution point mP (x, y), and the line segment is by set mark
Determined by point two contiguous tokens point therein；
(2) linear interpolation method is used, mP points are projected to identified line segment；
(3) obtain subpoint R2 as solution point mP smart reconstruction point.
The present invention has following 2 beneficial effects：
1. with high performance-price ratio.The method proposed is only with two base stations, in the case of irredundant location information, fully
Using roadway position information, preferably every positioning precision index can be obtained, it is adaptable to underground coal mine alignment system and search and rescue system
System.
2. innovatively NLOS signals are positioned for target, with bigger universality.The method proposed is fully excavated
Ranging information in NLOS signals, the influence that the positioning precision caused by significantly reducing NLOS signals declines, unites with LOS signals
One is applied to the positioning of tunnel target, can realize the positioning of target under more general winding roadway, compared with other methods,
With bigger universality.A reliable technology branch is provided to implement the quick effectively emergency management and rescue in colliery under complex environment
Hold.
Brief description of the drawings
Fig. 1 is the schematic diagram of a scenario of winding roadway positioning of the present invention.
Fig. 2 is the flow chart of localization method of the present invention.
Embodiment
The present invention is further described with reference to the accompanying drawings and examples.
Fig. 1 is the schematic diagram of a scenario of winding roadway object localization method in colliery of the present invention, using 2 base station TOA ranging localizations,
Locating base station B1, B2 is located at the two ends of winding roadway, using the line of B1, B2 base stations as x-axis, and tunnel cross direction is y-axis, with
B1 base stations are origin, set up positioning plane coordinate system；The tunnel length Ls between B1, B2 is determined, is used it is ensured that Ls is no more than
Ranging electromagnetic wave signal effective propagation distance, meanwhile, demarcate M1 in tunnel, 5 index points such as M2 ... M5 are successively
B1, camber line left end point, arc centers point, camber line right endpoint, B2.Now needing to position mobile target rP, L1 and d2 is measured through TOA
Obtained destination node rP to base station B1 and B2 distance, due to direct path, institute being not present between destination node rP to base station B1
The distance of survey is actually the length in tunnel between rP to base station B1, not the air line distance of the two, therefore is represented herein with L1.No matter
It is NLOS states or los state, it, with error, is not accurate distance value that the distance measured by TOA, which is all, therefore is referred to as
Pseudorange.The flow chart of Fig. 2 localization methods of the present invention is contacted below, and the positioning to mobile target point rP is completed by following steps：
(1) non line of sight pseudorange L1 is reconstructed, to obtain the mobile target rP under non line of sight state and the straight line of base station
Pseudorange, detailed step is as follows：
A. by Δ ε=L1+d2-Ls, the deviation interval Δ ε at rP two ends is obtained；
B. determine that Δ ε point midway falls between index point M4 and M5, simultaneous is asked by index point M4, M5 straight line determined
Deviate interval Δ ε point midway R1 coordinates；
C. R1 and B1 base stations air line distance d1 are obtained, and is used as using d1 L1 reconstruction value；
(2) observational equations and solution of the rP with locating base station position relationship are set up.
Wherein (x1, y1) (x2, y2) is respectively B1 and B2 coordinate, and (x, y) is mobile target point rP coordinate.Simultaneous
1., 2. equation can be solved (x, y), and 1., 2. the method for Nonlinear System of Equations has a variety of for solution, and the present invention is changed using Taylor series exhibition
In generation, solves, and equation solution point 1., 2. and rP actual value still have larger error, and therefore, next solution point mP is entered again
Row essence reconstruct.
(3) smart reconstruct is carried out to the position mP (x, y) of solution point.Essence reconstruct follows these steps to implement：
A. the index point set by simultaneous, the x values of mP points are compared with each index point, determine solution point mP (x, y) location
Between the interval that is indicated by line segment M4M5；
B. line segment M4M5 linear equation can be obtained by M4M5, using linear interpolation method, mP points are projected to line segment M4M5；
C. the subpoint R2 obtained as solution point mP smart reconstruction point；
(4) Kalman filtering is filtered optimization to R2, further lifts positioning precision, so as to complete the positioning to rP.
Kalman filtering state equation using the first order motion equation that is shown below describe roadway moving target with
Machine motion state：
S (k)=Φk/k-1S(k-1)+GW(k-1)
Wherein,Represent the displacement in x directions and y directions, speed.State transfer matrixWherein T represents the sampling time of Kalman filtering.Driven for system noise
Gust, system noise sequence is
The observational equation of Kalman filtering is：Z (k)=HS (k)+Q (k), wherein observing matrix
Q (k) is observation noise variance matrix.Set
The input observation of Kalman filtering is the coordinate value of R2 points, and filtering output is rP unbiased esti-mator, further excellent
The precision of R2 point estimate is changed.So as to complete the positioning to rP.
When point to be determined is located at close to base station B1 sides, then, it is in non line of sight state with B2 sides, with examples detailed above
Cited B1 non line of sight situations, method is completely the same, the fact that this is apparent, therefore will not be described here.
The experiment of a reality is given below.Average curvature is used hereinTo represent the degree of crook of the passage,
Wherein Δ α represents the changing value of the tangent line corner at bending camber line two ends, and Δ s is the length of this section of camber line.The shaped form of experimental selection
Underpass, channel width about 4.0m, high about 2.5m, true length about 80m, its mean camber line passage is about 4.1m, and average curvature is
0.192, locating base station B1 coordinate are (0,0), and base station B2 coordinates are (0,43.3), passage model of the mobile target point 2 base stations
Enclose interior movement.36 points are positioned using this method, statistics is as follows：Pseudorange d1 error mean is 5.1872, pseudorange d2's
Error mean is 5.183m, and position root-mean-square error is 0.891m.Although as can be seen that pseudorange has larger error, originally
The there is provided method position error precision of invention is ideal, illustrates that this method can make full use of NLOS information, and can be effective
Range error is resisted, being accurately positioned for winding roadway movement target is realized.
Claims (4)
1. one kind realizes colliery winding roadway object localization method using non line of sight signal, it is characterised in that described colliery is curved
Two sections of straight line tunnels that bent tunnel is connected respectively by one section of circular curve type tunnel part and at its two ends are constituted, using 2 station rangings
Plane positioning, 2 locating base station non line of sight placements, is respectively placed in two sections of straight line tunnels region, tunnel length therebetween is small
The ultimate range that can be propagated in the tunnel in used ranging radio；Using the line of two base stations as x-axis, the wide side in tunnel
Positioning plane coordinate system is set up to for y-axis；Pseudorange between mobile target and base station is obtained by TOA rangings, i.e., with measurement
The distance value of error；Described non line of sight signal refers to be surveyed when mobile node is in non line of sight state with one of base station
The pseudorange obtained, the positioning of its pseudorange measured under sighting distance state with another base station jointly for mobile target in winding roadway
Ranging information is provided.
2. one kind according to claim 1 realizes colliery winding roadway object localization method using non line of sight signal, it is special
Levy and be, described utilization non line of sight signal realizes colliery winding roadway object localization method, specifically includes following steps：
(1) 5 index points are set in the winding roadway of positioning is interval and the tunnel length Ls between two base stations is determined；5 marks
Will point is specifically located at the following location of winding roadway：In 2 base stations present position, the end positions and arc section of arc section
Point position；
(2) pseudorange for obtaining mobile target rP to 2 base station is measured by TOA；
(3) non line of sight pseudorange is reconstructed, to obtain the mobile target rP under non line of sight state and the straight line pseudorange of base station；
(4) foundation measurement equation is fastened in the elements of a fix：I=1,2；Wherein, diFor mobile mesh
Mark and the straight line pseudorange of i-th of base station, (xi,yi) for the position coordinates of i-th locating base station, (x, y) is mobile target rP position
Put coordinate；Equation is measured using Taylor series solution by iterative method, the position coordinates mP (x, y) of solution point is obtained；
(5) smart reconstruct is carried out to the position mP (x, y) of solution point, obtains the observation station R2 (x, y) after essence reconstruct；
(6) Kalman filter is designed, is inputted observation station R2 (x, y) coordinate as the observation of Kalman filter, card
Output valve after Thalmann filter is filtered for observation point coordinates is estimation of the mobile target in winding roadway actual value.
3. one kind according to claim 2 realizes colliery winding roadway object localization method using non line of sight signal, it is special
Levy and be, in the step (3), non line of sight pseudorange is reconstructed and comprised the following steps：
(1) by Δ ε=L1+d2-Ls, pseudorange biases the interval Δ ε, wherein L1 for obtaining mobile target rP two ends represent NLOS one end
Pseudorange value, d2 represents the pseudorange value of LOS one end；
(2) index point set by simultaneous, obtains deviation interval Δ ε point midway R1；
(3) R1 and NLOS one end base station distance d1 are obtained, and is used as using d1 L1 reconstruction value.
4. one kind according to claim 3 realizes colliery winding roadway object localization method using non line of sight signal, it is special
Levy and be, in the step (5), position mP (x, y) the progress essence reconstruct to solution point comprises the following steps：
(1) index point set by simultaneous, determines the line segment where solution point mP (x, y), the line segment be by set index point its
In two contiguous tokens points determined by；
(2) linear interpolation method is used, mP points are projected to identified line segment；
(3) obtain subpoint R2 as solution point mP smart reconstruction point.
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