CN101009942A - A cellular positioning system, method and device - Google Patents

Abstract

The invention discloses a cellular positioning method, comprising: A. A target mobile station to be positioned establishes communication with at least two reference mobile stations; the target mobile station and the reference mobile station respectively establish communication with at least two base stations; B. the between the target mobile station and the at least two base stations in communication, between the at least two reference mobile stations and the at least two base stations in communication, and between the target mobile station and the at least two reference mobile stations in communication Interacting test signals; C. Obtaining the time difference of arrival of the above three groups of test signals respectively; D. Calculating the position information of the target mobile station according to the acquired time difference of signal arrival. The invention also discloses a mobile station and a cellular positioning system. Adopting the present invention has the advantages of fundamentally reducing the lower limit of positioning errors and improving positioning accuracy.

Description

Cellular positioning system, method and device

Technical Field

The present invention relates to the field of mobile communications, and in particular, to a cellular positioning system, method, and apparatus.

Background

In cellular positioning systems, time-differential-of-arrival (TDOA) estimates between a mobile station and multiple base stations are a common way to locate the mobile station. How to improve the positioning accuracy is a problem that people are always exploring, and since a positioning mode based on TDOA estimation needs to solve a group of nonlinear equations set established based on TDOA estimation, researchers mostly reduce the lower limit of the calculation accuracy by solving the nonlinear equations set algorithm. Foy, an optimization algorithm is proposed, which first linearizes the system of nonlinear equations and then gradually minimizes the error by means of Least-squares (LS) algorithm; friedlander provides a method for solving a nonlinear equation by applying spherical interpolation; abel proves that the optimal solution of the nonlinear equation system can be obtained by using a step-by-step attack and conquer (DAC) algorithm; the Taylor-series algorithm corrects and improves the result estimation value obtained by the last iteration by adopting the sum of local linear least squares errors in the iteration process, the algorithms aim at better approaching the lower limit of the positioning error without fundamentally reducing the lower limit of the positioning error, and the research on the lower limit of the positioning error shows that the main factors restricting the positioning accuracy comprise two factors: one is the number of devices participating in the positioning; another is the network channel characteristics. The existing positioning method only includes the target mobile station to be positioned and a plurality of cellular base stations communicating with the target mobile station, which greatly limits the number of devices participating in one independent positioning, and simultaneously, due to the limitation of the bandwidth of the cellular network, the TDOA estimated value obtained by cellular signal transmission has low precision, and the two factors cause the final positioning precision to be low.

Disclosure of Invention

The technical problem to be solved by the embodiments of the present invention is to provide a system, a method and an apparatus for cellular positioning. The lower limit of the positioning error can be fundamentally reduced, and the positioning precision is improved.

In order to solve the above technical problem, the present invention provides a method for cellular positioning, including:

A. a target mobile station needing to be positioned establishes communication with at least two reference mobile stations; the target mobile station and the reference mobile station are communicated with at least two base stations respectively;

B. the target mobile station interacts test signals with the at least two base stations of communication, the at least two reference mobile stations with the at least two base stations of communication, and the target mobile station with the at least two reference mobile stations of communication;

C. respectively acquiring arrival time differences of the three groups of test signals;

D. and calculating the position information of the target mobile station according to the acquired signal arrival time difference.

Preferably, the target mobile station and the reference mobile station communicate by using a short-range communication technology within a communication distance of 10-20 m.

Preferably, step B includes:

the at least two base stations respectively transmit test signals to the target mobile station and each of the at least two reference mobile stations; the at least two reference mobile stations send test signals to the target mobile station;

correspondingly, step C comprises:

the target mobile station measures the difference of arrival time of the test signals sent by the at least two base stations;

each mobile station in the at least two reference mobile stations measures the difference of arrival time of the test signals transmitted by the at least two base stations;

the target mobile station measures a difference in arrival times of the test signals transmitted by the at least two reference mobile stations.

Alternatively, step B comprises:

the target mobile station respectively sends test signals to the at least two base stations and the at least two reference mobile stations; the at least two reference mobile stations transmit test signals to the at least two base stations;

correspondingly, step C comprises:

the target mobile station measures the arrival time difference of the test signals sent to the at least two base stations;

the target mobile station measuring the difference of arrival time of the test signals sent to the at least two reference mobile stations;

each of the at least two reference mobile stations measures a difference in arrival times of the test signals transmitted to the at least two base stations.

Preferably, step D includes:

d01, the position server in the network obtains the initial position coordinate value of the target mobile station and the reference mobile station;

d02, calculating the position information of the target mobile station by using Taylor-series iterative algorithm according to the arrival time difference value obtained by measurement and the obtained initial position coordinate value.

Alternatively, step D comprises:

d11, the target mobile station obtains the initial position coordinate values of the target mobile station and the reference mobile station;

d12, calculating the position information of the target mobile station by using Taylor-series iterative algorithm according to the arrival time difference value obtained by measurement and the obtained initial position coordinate value.

Correspondingly, an embodiment of the present invention provides a mobile station, including:

the first transceiver is used for interacting positioning test signals with a communication cellular base station;

the second transceiver, is used for positioning the test signal with the interaction between the mobile stations communicating;

the first measuring device is used for measuring and acquiring the signal arrival time difference of the test signal interacted between the mobile station and a communication cellular base station;

and the second measuring device is used for measuring and acquiring the signal arrival time difference of the test signal interacted between the mobile station and the communication mobile station.

Preferably, the mobile station further comprises:

and the calculating device is used for calculating the position information of the mobile station according to the difference value of the arrival time of the signals acquired by the first measuring device and the second measuring device.

Correspondingly, the embodiment of the present invention further provides a cellular positioning system, which includes a target mobile station to be positioned, at least two reference mobile stations, at least two cellular base stations, and a location server, wherein:

the target mobile station is used for measuring the difference of the arrival time of the positioning test signals interacted with the at least two base stations and measuring the difference of the arrival time of the positioning test signals interacted with the at least two reference mobile stations;

the reference mobile station is used for measuring the arrival time difference of the positioning test signals interacted with the at least two base stations;

the base station is used for interacting positioning test signals with the target mobile station and the reference mobile station;

and the position server is used for calculating the position information of the target mobile station according to the signal arrival time difference obtained by the measurement of the target mobile station and the reference mobile station.

Correspondingly, another cellular positioning system is provided in an embodiment of the present invention, including a target mobile station to be positioned, at least two reference mobile stations, and at least two cellular base stations, wherein:

the reference mobile station is used for measuring the arrival time difference of the positioning test signals interacted with the at least two base stations;

the target mobile station is used for measuring the difference of the arrival time of the positioning test signals interacted with the at least two base stations and measuring the difference of the arrival time of the positioning test signals interacted with the at least two reference mobile stations; calculating the position information of the target mobile station according to the signal arrival time difference obtained by self measurement and the signal arrival time difference obtained by the reference mobile station;

the base station is used for interacting positioning test signals with the target mobile station and the reference mobile station.

The embodiment of the invention has the following beneficial effects:

firstly, the cellular positioning system of the embodiment of the invention introduces a plurality of reference mobile stations to cooperate with the cellular base station to position the target mobile station, thereby greatly increasing the number of devices participating in one positioning process;

secondly, the TDOA estimated value is obtained through the communication signals transmitted among the mobile stations, and the obtained TDOA estimated value has high accuracy due to the fact that the network communication channel characteristics of communication among the mobile stations are excellent.

Drawings

FIG. 1 is a schematic block diagram of one embodiment of a cellular positioning system of the present invention;

FIG. 2 is a schematic block diagram of another embodiment of the cellular positioning system of the present invention;

FIG. 3 is a block diagram of one embodiment of a mobile station of the present invention;

fig. 4 is a flow chart of one embodiment of a cellular positioning method of the present invention;

fig. 5 is a flow chart of another embodiment of the cellular location method of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings.

FIG. 1 is a schematic block diagram of one embodiment of a cellular positioning system of the present invention; the cellular system of this embodiment comprises a target mobile station 10, at least two reference mobile stations 20, at least two base stations 30, and a location server 40, wherein:

the target mobile station 10 is configured to measure a difference between arrival times of the positioning test signals interacting with the at least two base stations 30 and to measure a difference between arrival times of the positioning test signals interacting with the at least two reference mobile stations 20. In a specific implementation, the way that the target mobile station 10 and the at least two base stations 30 interactively locate the test signal may be that the target mobile station 10 sends the test signal to the at least two base stations 30, or that the at least two base stations 30 send the test signal to the target mobile station 10. The target mobile station 10 interacts with at least two reference mobile stations 20 in a positioning test signal interaction manner between the reference mobile station 10 and the base station 30.

Preferably, the target mobile station 10 and the reference mobile station 20 communicate using a short-range communication technique between communication distances of 10-20 m. Such as ultra-wideband technology or Zigbee technology. Because the short-distance communication technologies have wide bandwidth, the network communication channel characteristics of the communication between the mobile stations are better, and therefore the TDOA estimated value obtained through the communication signals transmitted between the mobile stations in the embodiment of the invention has higher accuracy.

The reference mobile station 20 is configured to measure a difference in arrival time of the positioning test signals interactively with the at least two base stations 30. In a specific implementation, the reference mobile station 20 interacts with at least two base stations 30 in the same way as the target mobile station 10 interacts with the base stations 30.

The base station 30 is configured to interact with the target mobile station 10 and the reference mobile station 20 through positioning signals.

The location server 40. For calculating the position information of the target mobile station according to the difference of the arrival time of the signals measured and obtained by the target mobile station 10 and the reference mobile station 20.

Preferably, in this embodiment, the location server 40 calculates the location information of the target mobile station 10 by using a Taylor-series iterative algorithm.

FIG. 2 is a schematic block diagram of another embodiment of the cellular positioning system of the present invention; the cellular system of this embodiment, which includes the target mobile station 60, at least two reference mobile stations 70, and at least two base stations 80, differs from the cellular system shown in fig. 1 only in that the target mobile station 60 itself includes a functional module that calculates the target mobile station location information. Other structural components of this embodiment are the same as those of the first embodiment, and will not be described repeatedly.

Correspondingly, in a specific implementation, the function module for measuring the time difference of arrival of the test signal may also be disposed in the base station.

The cellular system of the embodiment of the present invention is exemplified belowThe specific implementation process for positioning the target mobile station comprises the following steps: DS represents target mobile station, RS represents reference mobile station, B represents base station, DS and N base stations B_iCellular communication is achieved between (i 1.... multidot.n). the DS acquires a set of TDOA measurements via test signals interacted between the DS and bs, e.g., the acquired DS and bs B₁Interactive test signal and DS and base station B_jThe TDOA value of the (j 2.., N) interacted test signal is expressed as: <math> <mrow> <msub> <mi>t</mi> <mrow> <mrow> <mo>(</mo> <mi>D</mi> <mo>)</mo> </mrow> <mi>j</mi> <mn>1</mn> </mrow> </msub> <mo>=</mo> <msubsup> <mi>t</mi> <mrow> <mrow> <mo>(</mo> <mi>D</mi> <mo>)</mo> </mrow> <mi>j</mi> <mn>1</mn> </mrow> <mi>o</mi> </msubsup> <mo>+</mo> <mi>&Delta;</mi> <msub> <mi>t</mi> <mrow> <mrow> <mo>(</mo> <mi>D</mi> <mo>)</mo> </mrow> <mi>j</mi> <mn>1</mn> </mrow> </msub> </mrow> </math> wherein: t is t_(D)j1Representing the actual measured TDOA value, t_(D)j1 ^oRepresenting true TDOA values, Δ t_(D)j1Representing an estimation error;

further, according to $t_{\left(D\right)j1}^o=r_{\left(D\right)j1}^o/c=(r_{\left(D\right)j}^o-r_{\left(D\right)1}^o)/c$ Base station B can be obtained_jAnd base station B₁Set of distance differences r to DS_(D)j1 ^oWhere c represents the radio wave propagation rate,

$r_{\left(D\right)j}^o=|\mathrm{DS}-B_j|=\sqrt{{(x_D-x_j)}^2+{(y_D-y_j)}^2+{(z_D-z_j)}^2}$

$r_{\left(D\right)1}^o=|\mathrm{DS}-B_1|=\sqrt{{(x_D-x_1)}^2+{(y_D-y_1)}^2+{(z_D-z_1)}^2}$

wherein DS ═ x_D，y_D，z_D]^TRepresenting target mobile station coordinates, B_j＝[x_j，y_j，z_j]^T(j ═ 2.., N) denotes base station B_jAnd (4) coordinates.

Meanwhile, the DS communicates with M reference mobile stations RS within 10-20M nearby, the RS acquires a group of TDOA measured values through test signals interacted between the RS and the base station B, and correspondingly, the acquired reference mobile stations RS_i(i ═ 1.., M) and base station B₁Interactive test signals and RS_iAnd base station B_jThe TDOA value of the (j 2...., N) interacted test signal is expressed as: <math> <mrow> <msub> <mi>t</mi> <mrow> <mrow> <mo>(</mo> <mi>Ri</mi> <mo>)</mo> </mrow> <mi>j</mi> <mn>1</mn> </mrow> </msub> <mo>=</mo> <msubsup> <mi>t</mi> <mrow> <mrow> <mo>(</mo> <mi>Ri</mi> <mo>)</mo> </mrow> <mi>j</mi> <mn>1</mn> </mrow> <mi>o</mi> </msubsup> <mo>+</mo> <mi>&Delta;</mi> <msub> <mi>t</mi> <mrow> <mrow> <mo>(</mo> <mi>Ri</mi> <mo>)</mo> </mrow> <mi>j</mi> <mn>1</mn> </mrow> </msub> </mrow> </math> wherein: t is t_(Ri)j1Representing the actual measured TDOA value, t_(Ri)j1 ^oRepresenting true TDOA value, Δ_t(Ri)j1Representing an estimation error;

further, according to $t_{\left(\mathrm{Ri}\right)j1}^o=r_{\left(\mathrm{Ri}\right)j1}^o/c=(r_{\left(\mathrm{Ri}\right)j}^o-r_{\left(\mathrm{Ri}\right)1}^o)/c,$ Base station B can be obtained_jAnd base station B₁To RS_iA set of distance differences r_(Ri)j1 ^oWhere c represents the radio wave propagation rate,

$r_{\left(\mathrm{Ri}\right)j}^o=|R{S}_i-B_j|=\sqrt{{(x_{\mathrm{Ri}}-x_j)}^2+{(y_{\mathrm{Ri}}-y_j)}^2+{(z_{\mathrm{Ri}}-z_j)}^2}$

$r_{\left(\mathrm{Ri}\right)1}^o=|R{S}_i-B_1|=\sqrt{{(x_{\mathrm{Ri}}-x_1)}^2+{(y_{\mathrm{Ri}}-y_1)}^2+{(z_{\mathrm{Ri}}-z_1)}^2}$

wherein RS_i＝[x_Ri，y_Ri，z_Ri]^T(i 1.., M) denotes a reference mobile station RS_iAnd (4) coordinates.

At the same time, the DS acquires a set of TDOA measured values through the interactive test signal between the DS and the RS, and correspondingly, the acquired DS and the RS of the reference mobile station₁Interactive test signal and DS and reference mobile station RS_jThe TDOA value of the (j 2...., N) interacted test signal is expressed as: <math> <mrow> <msub> <mover> <mi>t</mi> <mo>^</mo> </mover> <mrow> <mi>j</mi> <mn>1</mn> </mrow> </msub> <mo>=</mo> <msubsup> <mover> <mi>t</mi> <mo>^</mo> </mover> <mrow> <mi>j</mi> <mn>1</mn> </mrow> <mi>o</mi> </msubsup> <mo>+</mo> <mi>&Delta;</mi> <msub> <mover> <mi>t</mi> <mo>^</mo> </mover> <mrow> <mi>j</mi> <mn>1</mn> </mrow> </msub> </mrow> </math> wherein:

represents the actual measured TDOA value and,

represents the true value of the TDOA value,

representing an estimation error;

further, according to ${\hat{t}}_{j1}^o={\hat{r}}_{j1}^o/c=({\hat{r}}_j^o-{\hat{r}}_1^o)/c,$ Reference mobile station RS can be obtained₁And reference mobile station RS_jA set of distance differences to the target mobile station DSWherein c represents the radio wave propagation rate

${\hat{r}}_j^o=|\mathrm{DS}-{\mathrm{RS}}_j|=\sqrt{{(x_{\mathrm{Rj}}-x_D)}^2+{(y_{\mathrm{Rj}}-y_D)}^2+{(z_{\mathrm{Rj}}-z_D)}^2}$

${\hat{r}}_1^o=|\mathrm{DS}-R{S}_1|=\sqrt{{(x_{R1}-x_D)}^2+{(y_{R1}-y_D)}^2+{(z_{R1}-z_D)}^2}$

To this end, the communication network between the cellular network and the mobile station realizes the co-location of the target mobile station DS.

And then, simultaneously substituting the distance difference values corresponding to the three groups of TDOA measured values into a Taylor-series iterative algorithm in the position server, wherein the initial estimation of the position coordinates of the DS and each RS is required for the first iteration as an iterative initial value, so that the position server firstly obtains the initial position coordinate values of the DS and each RS, then simultaneously calculates the updated estimation values of the position coordinates of the DS and each RS for each iteration, and sets all the updated estimation values as the initial values of the next iteration. Until the estimation error is less than a certain tolerance range, the iterative algorithm is terminated and a final position estimate for the DS is obtained. The basic flow is as follows:

<math> <mfenced open='{' close=''> <mtable> <mtr> <mtd> <mi>k</mi> <mo>=</mo> <mn>0</mn> </mtd> </mtr> <mtr> <mtd> <mi>while</mi> <mo>|</mo> <mo>|</mo> <msup> <mi>&delta;&theta;</mi> <mrow> <mo>(</mo> <mi>k</mi> <mo>)</mo> </mrow> </msup> <mo>|</mo> <mo>|</mo> <mo>></mo> <mi>&epsiv;</mi> </mtd> </mtr> <mtr> <mtd> <msup> <mi>&delta;&theta;</mi> <mrow> <mo>(</mo> <mi>k</mi> <mo>+</mo> <mn>1</mn> <mo>)</mo> </mrow> </msup> <mo>=</mo> <msup> <mrow> <mo>[</mo> <msup> <mi>A</mi> <mrow> <mrow> <mo>(</mo> <mi>k</mi> <mo>)</mo> </mrow> <mi>T</mi> </mrow> </msup> <msup> <mi>Q</mi> <mrow> <mo>-</mo> <mn>1</mn> </mrow> </msup> <msup> <mi>A</mi> <mrow> <mo>(</mo> <mi>k</mi> <mo>)</mo> </mrow> </msup> <mo>]</mo> </mrow> <mrow> <mo>-</mo> <mn>1</mn> </mrow> </msup> <msup> <mi>A</mi> <mrow> <mrow> <mo>(</mo> <mi>k</mi> <mo>)</mo> </mrow> <mi>T</mi> </mrow> </msup> <msup> <mi>Q</mi> <mrow> <mo>-</mo> <mn>1</mn> </mrow> </msup> <msup> <mi>W</mi> <mrow> <mo>(</mo> <mi>k</mi> <mo>)</mo> </mrow> </msup> <mo>,</mo> </mtd> </mtr> <mtr> <mtd> <msup> <mi>&theta;</mi> <mrow> <mrow> <mo>(</mo> <mi>k</mi> <mo>+</mo> <mn>1</mn> <mo>)</mo> </mrow> <mo>=</mo> <msup> <mi>&theta;</mi> <mrow> <mo>(</mo> <mi>k</mi> <mo>)</mo> </mrow> </msup> <mo>+</mo> <msup> <mi>&delta;&theta;</mi> <mrow> <mo>(</mo> <mi>k</mi> <mo>+</mo> <mn>1</mn> <mo>)</mo> </mrow> </msup> <mo>,</mo> </mrow> </msup> </mtd> </mtr> <mtr> <mtd> <mi>k</mi> <mo>=</mo> <mi>k</mi> <mo>+</mo> <mn>1</mn> </mtd> </mtr> </mtable> </mfenced> </math> wherein,

θ＝[DS^T，RS^T]^Tincluding all mobile station coordinates (target mobile station and reference mobile station), where: DS ═ x_D，y_D，z_D]^T RS＝[RS₁ ^T，...， RS_M ^T]^T RS_i＝[x_Ri，y_Ri，z_Ri]^T；

δθ＝θ-θ_g＝[δDS^T，δRS^T]^TRepresenting the difference between the theta and the theta before and after each iteration;

f (θ) ═ T ═ M-E, where:

t is the true distance difference corresponding to TDOA and is represented by a function f (theta);

m is the observation distance difference corresponding to TDOA

E is the error between the observed and true range difference corresponding to TDOA

$T={[{{r_{\left(D\right)}^o}^T,r_{\left(R\right)}^o}^T,{\hat{r}}^{\mathrm{oT}}]}^T$

$r_{\left(D\right)}^o={[r_{\left(D\right)21}^o,...,r_{\left(D\right)N1}^o]}^T$

$r_{\left(R\right)}^o=[{{r_{\left(R1\right)}^o}^T,...,{r_{\left(\mathrm{Ri}\right)}^o}^T,...,{r_{\left(\mathrm{RM}\right)}^o}^T]}^T,r_{\left(\mathrm{Ri}\right)}^o={[r_{\left(\mathrm{Ri}\right)21}^o,...,r_{\left(\mathrm{Ri}\right)N1}^o]}^T$

${\hat{r}}^o={[{\hat{r}}_{21}^o,...,{\hat{r}}_{M1}^o]}^T$

$M={[r_{\left(D\right)21},...,r_{\left(D\right)N1},r_{\left(\mathrm{Ri}\right)21},...,r_{\left(\mathrm{Ri}\right)N1},{\hat{r}}_{21},...,{\hat{r}}_{M1}]}^T$

<math> <mrow> <mi>E</mi> <mo>=</mo> <msup> <mrow> <mo>[</mo> <mi>c</mi> <msub> <mi>&Delta;t</mi> <mrow> <mrow> <mo>(</mo> <mi>D</mi> <mo>)</mo> </mrow> <mn>21</mn> </mrow> </msub> <mo>,</mo> <mo>.</mo> <mo>.</mo> <mo>.</mo> <mo>,</mo> <msub> <mi>c&Delta;t</mi> <mrow> <mrow> <mo>(</mo> <mi>D</mi> <mo>)</mo> </mrow> <mi>N</mi> <mn>1</mn> </mrow> </msub> <mo>,</mo> <mi>c&Delta;</mi> <msub> <mi>t</mi> <mrow> <mrow> <mo>(</mo> <mi>Ri</mi> <mo>)</mo> </mrow> <mn>21</mn> </mrow> </msub> <mo>,</mo> <mo>.</mo> <mo>.</mo> <mo>.</mo> <mo>,</mo> <msub> <mi>c&Delta;t</mi> <mrow> <mrow> <mo>(</mo> <mi>Ri</mi> <mo>)</mo> </mrow> <mi>N</mi> <mn>1</mn> </mrow> </msub> <mo>,</mo> <msub> <mrow> <mi>c&Delta;</mi> <mover> <mi>t</mi> <mo>^</mo> </mover> </mrow> <mn>21</mn> </msub> <mo>,</mo> <mo>.</mo> <mo>.</mo> <mo>.</mo> <mo>,</mo> <msub> <mrow> <mi>c&Delta;</mi> <mover> <mi>t</mi> <mo>^</mo> </mover> </mrow> <mrow> <mi>M</mi> <mn>1</mn> </mrow> </msub> <mo>]</mo> </mrow> <mi>T</mi> </msup> </mrow> </math>

W＝M-f(θ)|_θ＝θgAfter theta is updated after each iteration is finished, new theta is added_gSubstituting f (theta), recalculating the real distance value corresponding to the TDOA, and recalculating the difference value w between the real distance value and the observation distance value corresponding to the TDOA; $Q=\left[\begin{array}{ccc}{Q}_D& 0& 0\\ 0& Q_R& 0\\ 0& 0& \hat{Q}\end{array}\right]$ for measuring error covariance matrix

Wherein:

Q_R＝diag[Q₁，..，Q_Ri，...，Q_M]， <math> <mrow> <msub> <mi>Q</mi> <mi>Ri</mi> </msub> <mo>=</mo> <msup> <mi>c</mi> <mn>2</mn> </msup> <mi>E</mi> <mo>[</mo> <msub> <mi>&Delta;t</mi> <mrow> <mo>(</mo> <mi>Ri</mi> <mo>)</mo> </mrow> </msub> <msubsup> <mi>&Delta;t</mi> <mrow> <mo>(</mo> <mi>Ri</mi> <mo>)</mo> </mrow> <mi>T</mi> </msubsup> <mo>]</mo> </mrow> </math> Δt_(Ri)＝[Δt_(Ri)21，...，Δt_(Ri)N1]

<math> <mrow> <msub> <mi>Q</mi> <mi>D</mi> </msub> <mo>=</mo> <msup> <mi>c</mi> <mn>2</mn> </msup> <mi>E</mi> <mo>[</mo> <msub> <mi>&Delta;t</mi> <mrow> <mo>(</mo> <mi>D</mi> <mo>)</mo> </mrow> </msub> <msubsup> <mi>&Delta;</mi> <mrow> <mo>(</mo> <mi>D</mi> <mo>)</mo> </mrow> <mi>T</mi> </msubsup> <mo>]</mo> </mrow> </math> Δt_(D)＝[Δt_(D)21，...，Δt_(D)N1]

<math> <mrow> <mover> <mi>Q</mi> <mo>^</mo> </mover> <mo>=</mo> <msup> <mi>c</mi> <mn>2</mn> </msup> <mi>E</mi> <mo>[</mo> <mo></mo> <mrow> <mover> <mi>&Delta;</mi> <mo>^</mo> </mover> <mi>t</mi> <msup> <mrow> <mover> <mi>&Delta;</mi> <mo>^</mo> </mover> <mi>t</mi> </mrow> <mi>T</mi> </msup> </mrow> <mo>]</mo> </mrow> </math> <math> <mrow> <mover> <mi>Q</mi> <mo>^</mo> </mover> <mo>=</mo> <msup> <mi>c</mi> <mn>2</mn> </msup> <mi>E</mi> <mo>[</mo> <mrow> <mover> <mi>&Delta;</mi> <mo>^</mo> </mover> <mi>t</mi> <mrow> <mover> <mi>&Delta;</mi> <mo>^</mo> </mover> <mi></mi> <msup> <mi>t</mi> <mi>T</mi> </msup> </mrow> </mrow> <mo>]</mo> </mrow> </math>

<math> <mrow> <mrow> <mi>A</mi> <mo>=</mo> <mfenced open='[' close=']'> <mtable> <mtr> <mtd> <mfrac> <msubsup> <mrow> <mo>&PartialD;</mo> <mi>r</mi> </mrow> <mrow> <mo>(</mo> <mi>D</mi> <mo>)</mo> </mrow> <mi>o</mi> </msubsup> <mrow> <mo>&PartialD;</mo> <mi>DS</mi> </mrow> </mfrac> </mtd> <mtd> <mfrac> <mrow> <msubsup> <mrow> <mo>&PartialD;</mo> <mi>r</mi> </mrow> <mrow> <mo>(</mo> <mi>D</mi> <mo>)</mo> </mrow> <mi>o</mi> </msubsup> <mtext></mtext> </mrow> <mrow> <mo>&PartialD;</mo> <mi>RS</mi> </mrow> </mfrac> </mtd> </mtr> <mtr> <mtd> <mfrac> <mrow> <mo>&PartialD;</mo> <msubsup> <mi>r</mi> <mrow> <mo>(</mo> <mi>R</mi> <mo>)</mo> </mrow> <mi>o</mi> </msubsup> </mrow> <mrow> <mo>&PartialD;</mo> <mi>DS</mi> </mrow> </mfrac> </mtd> <mtd> <mfrac> <msubsup> <mrow> <mo>&PartialD;</mo> <mi>r</mi> </mrow> <mrow> <mo>(</mo> <mi>R</mi> <mo>)</mo> </mrow> <mi>o</mi> </msubsup> <mrow> <mo>&PartialD;</mo> <mi>RS</mi> </mrow> </mfrac> </mtd> </mtr> <mtr> <mtd> <mfrac> <msup> <mrow> <mo>&PartialD;</mo> <mover> <mi>r</mi> <mo>^</mo> </mover> </mrow> <mi>o</mi> </msup> <mrow> <mo>&PartialD;</mo> <mi>DS</mi> </mrow> </mfrac> </mtd> <mtd> <mfrac> <msup> <mrow> <mo>&PartialD;</mo> <mover> <mi>r</mi> <mo>^</mo> </mover> </mrow> <mi>o</mi> </msup> <mrow> <mo>&PartialD;</mo> <mi>RS</mi> </mrow> </mfrac> </mtd> </mtr> </mtable> </mfenced> <mo>|</mo> </mrow> <mi>&theta;</mi> <mo>=</mo> <msub> <mi>&theta;</mi> <mi>g</mi> </msub> </mrow> </math> is f (theta) at theta_gFirst order partial derivatives with respect to theta

k is the iteration number.

The embodiment of the invention calculates the position information of the target mobile station and the position information of the reference mobile station at the same time, thereby realizing the purpose of positioning a plurality of mobile stations at the same time.

Correspondingly, the embodiment of the invention provides a mobile station. Fig. 3 is a block diagram of an embodiment of a mobile station of the present invention; the mobile station of this embodiment comprises first transceiver means 52, second transceiver means 53, first measuring means 54, second measuring means 55 and calculating means 56, wherein:

first transceiver means 52 for interacting with the communicating cellular base stations to locate the test signal;

second transceiving means 53, configured to interactively locate the test signal with the communicating mobile station;

a first measuring device 54 for measuring the difference of signal arrival time of the test signal for acquiring the interaction between the mobile station and the communication cellular base station;

second measuring means 55 for measuring the difference in signal arrival times of the test signals for acquiring the interaction of the mobile station with the communicating mobile station.

A calculating device 56, configured to calculate the location information of the mobile station according to the difference between the arrival times of the signals obtained by the first measuring device 54 and the second measuring device 55.

Accordingly, an embodiment of the present invention provides a method for cellular positioning, and referring to fig. 4, it is a flowchart of a first embodiment of the cellular positioning method of the present invention; the positioning method of the embodiment specifically includes:

step S100, a target mobile station needing to be positioned establishes communication with at least two reference mobile stations; the target mobile station and the reference mobile station establish communication with at least two base stations, respectively. In one embodiment, the target mobile station and the reference mobile station preferably communicate by using a short-range communication technology within a communication distance of 10-20 m. Such as ultra-wideband technology or Zigbee technology. Because the short-distance communication technologies have wide bandwidth, the network communication channel characteristics of the communication between the mobile stations are better, and therefore the TDOA estimated value obtained through the communication signals transmitted between the mobile stations in the embodiment of the invention has higher accuracy.

Step S101, at least two base stations respectively send test signals to the target mobile station and the at least two reference mobile stations; the at least two reference mobile stations transmit test signals to the target mobile station.

Step S102, the target mobile station and each of the at least two reference mobile stations measure a difference in arrival time of the test signal.

In step S103, the location server obtains initial location coordinate values of the target mobile station and the reference mobile station.

And step S104, calculating the position information of the target mobile station by adopting a Taylor-series iterative algorithm according to the obtained arrival time difference value and the obtained initial position coordinate value.

Referring to fig. 5, a flow chart of another embodiment of the cellular location method of the present invention is shown; the positioning method of the embodiment specifically includes:

step S200, a target mobile station needing to be positioned establishes communication with at least two reference mobile stations; the target mobile station and the reference mobile station establish communication with at least two base stations, respectively.

Step S201, the target mobile station sends test signals to the at least two base stations and the at least two reference mobile stations respectively; the at least two reference mobile stations transmit test signals to the at least two base stations.

Step S202, the target mobile station and each of the at least two reference mobile stations measure the time difference of arrival of the test signal.

In step S203, the target mobile station acquires initial position coordinate values of the target mobile station and the reference mobile station.

Step S204, calculating the position information of the target mobile station by adopting a Taylor-series iterative algorithm according to the arrival time difference value obtained by measurement and the obtained initial position coordinate value.

In the specific implementation, the measurement of the time difference of arrival of the test signal can also be realized by the base station; the embodiment of the invention calculates the position information of the target mobile station and the position information of the reference mobile station at the same time, thereby realizing the purpose of positioning a plurality of mobile stations at the same time.

The embodiment of the invention provides a positioning mode combining short-distance positioning and honeycomb positioning, which fundamentally reduces the lower limit of positioning errors and improves the positioning accuracy.

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention, and it is therefore to be understood that the invention is not limited by the scope of the appended claims.

Claims (10)

1. A cellular positioning method, comprising: A. The target mobile station to be positioned establishes communication with at least two reference mobile stations; the target mobile station and the reference mobile station respectively establish communication with at least two base stations; B. Between the target mobile station and the at least two base stations for communication, between the at least two reference mobile stations and the at least two base stations for communication, and between the target mobile station and the at least two communication base stations Refer to the interactive test signal between mobile stations; C. Obtain the arrival time difference of the above three groups of test signals respectively; D. Calculate the location information of the target mobile station according to the acquired signal arrival time difference. 2. The method according to claim 1, wherein the target mobile station communicates with the reference mobile station using short-distance communication technology within a communication distance of 10-20m. 3. The method of claim 2, wherein step B comprises: The at least two base stations respectively send test signals to the target mobile station and each of the at least two reference mobile stations; the at least two reference mobile stations send test signals to the target mobile station; Correspondingly, step C includes: The target mobile station measures a time difference of arrival of test signals sent by the at least two base stations; Each of the at least two reference mobile stations measures a time difference of arrival of test signals transmitted by the at least two base stations; The target mobile station measures a time difference of arrival of test signals transmitted by the at least two reference mobile stations. 4. The method of claim 2, wherein step B comprises: The target mobile station sends test signals to the at least two base stations and the at least two reference mobile stations respectively; the at least two reference mobile stations send test signals to the at least two base stations; Correspondingly, step C includes: the target mobile station measures a time difference of arrival of test signals sent to the at least two base stations; the target mobile station measures a difference in time of arrival of test signals sent to the at least two reference mobile stations; Each of the at least two reference mobile stations measures a difference in time of arrival of test signals sent to the at least two base stations. 5. The method according to any one of claims 1-4, characterized in that step D comprises: D01. The location server in the network acquires the initial location coordinate values of the target mobile station and the reference mobile station; D02. Calculate the position information of the target mobile station by using a Taylor-series iterative algorithm according to the time difference of arrival value obtained through measurement and the obtained initial position coordinate value. 6. The method according to any one of claims 1-4, characterized in that step D comprises: D11. The target mobile station acquires the initial position coordinate values of the target mobile station and the reference mobile station; D12. Calculate the location information of the target mobile station by using a Taylor-series iterative algorithm according to the time difference of arrival obtained through measurement and the obtained initial location coordinate value. 7. A mobile station, characterized by comprising: The first transceiver device is used for exchanging positioning test signals with the communicating cellular base stations; The second transceiver device is used for exchanging positioning test signals with the communicating mobile station; The first measuring device is used to measure and obtain the signal arrival time difference of the test signal interacted between the mobile station and the communicating cellular base station; The second measuring device is used for measuring and acquiring the signal arrival time difference of the test signal interacted between the mobile station and the communicating mobile station. 8. The mobile station of claim 7, further comprising: A computing device, configured to calculate the location information of the mobile station according to the signal arrival time difference obtained by the first and second measuring devices. 9. A cellular positioning system, comprising a target mobile station to be positioned, at least two reference mobile stations, at least two cellular base stations and a location server, wherein: The target mobile station is configured to measure a time difference of arrival of positioning test signals interacted with the at least two base stations and to measure a time difference of arrival of positioning test signals interacted with the at least two reference mobile stations; The reference mobile station is configured to measure a time difference of arrival of positioning test signals interacted with the at least two base stations; The base station is configured to exchange positioning test signals with the target mobile station and the reference mobile station; The location server is configured to calculate the location information of the target mobile station according to the signal arrival time difference obtained by measuring the target mobile station and the reference mobile station. 10. A cellular positioning system, comprising a target mobile station to be positioned, at least two reference mobile stations, and at least two cellular base stations, wherein: The reference mobile station is configured to measure a time difference of arrival of positioning test signals interacted with the at least two base stations; The target mobile station is configured to measure a time difference of arrival of positioning test signals interacted with the at least two base stations and to measure a time difference of arrival of positioning test signals interacted with the at least two reference mobile stations; and calculating the position information of the target mobile station according to the signal arrival time difference obtained by its own measurement and the signal arrival time difference obtained by the reference mobile station; The base station is configured to exchange positioning test signals with the target mobile station and the reference mobile station.

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