CN105093174A - Positioning algorithm based on signal gain and loss of 2.5G wireless network - Google Patents

Abstract

The invention discloses a positioning algorithm based on signal gain and loss of a 2.5G wireless network. The algorithm comprises the following steps: calculating antenna gain and signal loss of mobile terminals and base stations during signal transmission in the 2.5G wireless network; obtaining an estimated coordinate value of a mobile terminal communicating with each base station; through the estimated coordinate values and coordinate value information of each base station communicating with the mobile terminals, obtaining an average distance estimated error through calculation; according to the antenna gain, the loss, the average distance estimated error and the density of the base stations, obtaining coordinate values of the plurality of mobile terminals through calculation; and solving a sum of the coordinate values of the plurality of mobile terminals, and then performing averaging to obtain real coordinate values of the mobile terminals so that the mobile terminals are positioned under the condition of the signal loss of the 2.5G wireless network. The algorithm provided by the invention is based on full consideration of the loss of signals in a transmission process, is more accurate in positioning, is suitable for outdoor application, and also has a quite good positioning effect in indoor application.

Description

A kind of location algorithm based on the profit and loss of 2.5G wireless network signal

Technical field

The present invention is specifically related to a kind of location algorithm based on the profit and loss of 2.5G wireless network signal.

Background technology

At present, location for mobile terminal generally adopts GPS location technology, but because GPS location technology too relies on mobile terminal performance, scan by satellite, catch, pseudo range signals receives and the work such as positions calculations combines in terminal all over the body, thus cause low, the consuming time length of location sensitivity and the aspect defect such as terminal power consumption amount is large; Further, this GPS location technology only operates relatively good out of doors, but the local effect that cannot cover at indoor or satellite-signal is poor, and if overhead, position there is no the satellite of more than 3, system just cannot be located from cold start realization.

Except GPS location technology, also adopt three limit localization methods to position, this three limits location algorithm is according to the known coordinate of 3 reference modes and they are to the distance of unknown node, to the method that unknown node coordinate calculates; But the method does not consider the loss problem of signal in transmitting procedure and the gain situation of directional antenna, causes, and in 2.5G wireless network, this location algorithm can not satisfy the demands, and positioning precision is not high.

Summary of the invention

Be directed to the above-mentioned problems in the prior art, the object of this invention is to provide a kind of location algorithm based on the profit and loss of 2.5G wireless network signal, solve in 2.5G wireless network due to the problem that positioning precision is not high and location sensitivity is low that antenna gain, loss of signal cause.

To achieve these goals, the technical solution used in the present invention is:

A kind of location algorithm based on the profit and loss of 2.5G wireless network signal is provided, comprises:

Obtain the antenna gain of mobile terminal and base station Signal transmissions in 2.5G wireless network, and the loss produced in signals transmission;

Select several and mobile terminal in 2.5G wireless network, carry out the base station communicated, the distance between estimation mobile terminal and the base station of each selection; According to the distance value of each estimation, adopt weighted mass center algorithm, obtain the estimation coordinate figure carrying out the mobile terminal communicated with each base station;

By the coordinate figure information of the estimation coordinate figure of described mobile terminal and each base station with described communication of mobile terminal, calculate the mean distance evaluated error between described mobile terminal and base station;

According to antenna gain, the loss of Signal transmissions between described mobile terminal and base station, and mean distance evaluated error and base station density, calculate the coordinate figure carrying out the mobile terminal communicated with each base station;

The coordinate figure of several mobile terminals described is sued for peace, more on average, obtains the true coordinate value of described mobile terminal, realize based on the location to mobile terminal when the profit and loss of 2.5G wireless network signal.

In described acquisition 2.5G wireless network, between mobile terminal and base station, the method for the antenna gain of Signal transmissions is:

Following formulae discovery is adopted to obtain the antenna gain G (dBi) of Signal transmissions between mobile terminal and base station:

G(dBi)＝10lg{50000/(2θ3dB,E×2θ3dB,H)}

Wherein, 2 θ 3dB, E and 2 θ 3dB, H are respectively the lobe width of antenna on two principal planes, and 50000 is the empirical datas counted in 2.5G wireless network.

The method of the loss produced in signals transmission between described acquisition mobile terminal and base station is:

Adopt loss BD (d) that following formulae discovery signal produces in transmitting procedure:

$BD\left(d\right)=\{\stackrel{\‾}{BD}\left(d\right)+5klog\frac{dy}{dx}\}*\mathrm{\β}$

Wherein, BD (d) is the path loss of Signal transmissions after distance d; for the path loss of Signal transmissions after unit distance; K is path interference factor; 5 is the constant numerical value of signal in 2.5G wireless network; Dx is the received power of 2.5G wireless network, and dy is the emissive power of 2.5G wireless network; β is 2.5G wireless network correction constant numerical value, is 1.342.

The described distance value according to each estimation, adopts weighted mass center algorithm, obtains with the detailed process of the estimation coordinate figure of the mobile terminal of each base station communication being:

Described mobile terminal selects i base station from the base station that can communicate with it, estimates the distance between mobile terminal and each base station, according to each distance value estimated, adopts the estimation coordinate figure of the mobile terminal of following formulae discovery and each base station communication

$\left\{\begin{array}{c}{\tilde{x}}_i=\frac{\frac{x_{m1}}{d_1+d_2}+\frac{x_{m2}}{d_2+d_3}+...+\frac{x_{mi}}{d_i+d_1}}{\frac{1}{d_1+d_2}+\frac{1}{d_2+d_3}+...+\frac{1}{d_i+d_1}}*(1+\frac{BD\left(d\right)}{G\left(dBi\right)})\\ {\tilde{y}}_i=\frac{\frac{y_{m1}}{d_1+d_2}+\frac{y_{m2}}{d_2+d_3}+...+\frac{y_{mi}}{d_i+d_1}}{\frac{1}{d_1+d_2}+\frac{1}{d_2+d_3}+...+\frac{1}{d_i+d_1}}*(1+\frac{BD\left(d\right)}{G\left(dBi\right)})\end{array}\right.$

Wherein, for the estimation coordinate figure of the mobile terminal of mobile terminal and selected each base station communication; d _ifor the mobile terminal that estimates is to the distance of i-th base station; (x _mi, y _mi) be the coordinate figure of i-th base station.

By the coordinate figure information of the estimation coordinate figure of described mobile terminal and each base station with described communication of mobile terminal, the method calculating the mean distance evaluated error between described mobile terminal and base station is:

Adopt the mean distance evaluated error between following formulae discovery mobile terminal and base station

$\stackrel{\‾}{\mathrm{\ϵ}}=\frac{{\mathrm{\Σ}}_{i=1}^n\sqrt{{({\tilde{x}}_i-x_{mi})}^2+{({\tilde{y}}_i-y_{mi})}^2}}{N},(i=1,2...N)$

Wherein, for mean distance evaluated error; N is that algorithm performs number of times.

According to antenna gain, the loss of Signal transmissions between described mobile terminal and base station, and mean distance evaluated error and base station density, calculating the method for carrying out the coordinate figure of the mobile terminal communicated with each base station is:

Coordinate figure (the X of the mobile terminal communicated is carried out by following formulae discovery and certain base station _i, Y _i):

$\left\{\begin{array}{c}{X}_i=\frac{G\left(dBi\right)-BD\left(d\right)}{\stackrel{\‾}{\mathrm{\ϵ}}}*DA+x_{mi}\\ Y_i=\frac{G\left(dBi\right)-BD\left(d\right)}{\widetilde{\mathrm{\ϵ}}}*DA+y_{mi}\end{array}\right.$

Wherein, G (dBi) is antenna gain; BD (d) is the loss of signal in transmitting procedure; for mean distance evaluated error; DA is base station density; (x _mi, y _mi) be the coordinate figure of i-th base station.

Described base station density is obtained by following formulae discovery:

$DA=\left(\frac{AQ}{AQ+NQ}\right)\·100\%$

Wherein, AQ is the quantity of the base station selected; NQ be unselected can with the quantity of the base station of communication of mobile terminal.

The coordinate figure of several mobile terminals described is sued for peace, more on average, the method obtaining the true coordinate value of described mobile terminal is:

By the true coordinate (X of following formulae discovery mobile terminal _dst, Y _dst):

$(X_{dst},Y_{dst})=(\frac{1}{N}{\mathrm{\Σ}}_{i=1}^N{X}_i,\frac{1}{N}{\mathrm{\Σ}}_{i=1}^N{Y}_i),(i=1,2...N)$

Wherein, (X _dst, Y _dst) be the true coordinate value of mobile terminal; (X _i, Y _i) be the coordinate figure carrying out the mobile terminal communicated with each selected base station.

The loss that described signal produces in transmitting procedure produced by the impact of weather or barrier.

The network signaling parameters of the base station that the location algorithm of the 2.5G wireless network signal of the present invention profit and loss receives according to mobile terminal, consider antenna gain in 2.5G wireless network and signal in transmitting procedure by the loss that the impact of weather and/or barrier etc. produces, calculate above-mentioned antenna gain and loss of signal, again according to antenna gain, loss and base station density, obtain the coordinate figure of mobile terminal in mobile terminal and a base station communication situation, time again according to mobile terminal and multiple base station communication, the situation that communication coverage is overlapped, the coordinate of mobile terminal and multiple base station is sued for peace, and average, final realization is to the location of mobile terminal, this algorithm is that more accurate positioning, is not only applicable to open air, also has good locating effect in indoor based on having taken into full account the profit and loss that signal occurs in transmitting procedure.

Accompanying drawing explanation

Fig. 1 is the process flow diagram of an embodiment of the location algorithm based on the profit and loss of 2.5G wireless network signal of the present invention.

Embodiment

For making the object, technical solutions and advantages of the present invention clearly, below in conjunction with the specific embodiment of the invention and corresponding accompanying drawing, technical solution of the present invention is clearly and completely described.

Be the process flow diagram S100 adopting the location algorithm based on the profit and loss of 2.5G wireless network signal of the present invention see Fig. 1, Fig. 1; This process flow diagram S100 comprises step S101 to step S105;

In step S101, antenna gain and the loss of Signal transmissions are carried out in acquisition mobile terminal and base station in 2.5G wireless network; Must adopt the directional antenna of high-gain in 2.5G wireless network, antenna main lobe width is narrower, and gain is higher, and under specific power, the scope of gain its radiation higher is larger;

According to an embodiment of the application, in the signals transmission of mobile terminal and base station, first, calculate the antenna gain of signal in 2.5G wireless network transmissions, antenna gain G (dBi) can adopt following formula (1) to calculate:

G(dBi)＝10lg{50000/(2θ3dB,E×2θ3dB,H)}(1)

Wherein, (2 θ 3dB, E) and (2 θ 3dB, H) are respectively the lobe width of antenna on surface level and vertical plane, and 50000 is the empirical datas counted in 2.5G wireless network; (2 θ 3dB, E) is antenna lobe width in the horizontal plane, can be 45,60 or 90; (2 θ 3dB, H) is antenna lobe width on a vertical plane, can be 48,33,15 or 8;

According to an embodiment of the application, in 2.5G wireless network, (2 θ 3dB, E) be 45, (2 θ 3dB, H) is 48, according to formula G (dBi)=10lg (50000/45*48), namely try to achieve the gain of directional antenna.

Due in signal between the mobile terminal and the base station transmitting procedure, by the impact of weather or barrier, certain loss can be produced, loss BD (d) adopting following formula (2) to calculate signal to produce in transmitting procedure:

$BD\left(d\right)=\{\stackrel{\‾}{BD}\left(d\right)+5klog\frac{dy}{dx}\}*\mathrm{\β}---\left(2\right)$

Wherein, BD (d) is the path loss of Signal transmissions after distance d; for the path loss of Signal transmissions after unit distance; K is path interference factor; 5 is the constant numerical value of signal in 2.5G wireless network; Dx is the received power of 2.5G wireless network, and dy is the emissive power of 2.5G wireless network; β is 2.5G wireless network correction constant numerical value, is 1.342.

In step s 102, select several can with the base station of communication of mobile terminal, calculate and the estimation coordinate figure of each base communication mobile terminal;

According to an embodiment of the application, mobile terminal selects i base station from all base stations that can communicate with it, estimate the general distance between mobile terminal and each selected base station, again according to each distance value estimated, adopt weighted mass center algorithm, calculate the estimation coordinate figure carrying out the mobile terminal communicated with each selected base station weighted mass center algorithm is adopted to calculate sitting calibration method can adopt following formula (3) and (4) to calculate:

$\left\{\begin{array}{c}{\tilde{x}}_i=\frac{\frac{x_{m1}}{d_1+d_2}+\frac{x_{m2}}{d_2+d_3}+...+\frac{x_{mi}}{d_i+d_1}}{\frac{1}{d_1+d_2}+\frac{1}{d_2+d_3}+...+\frac{1}{d_i+d_1}}*(1+\frac{BD\left(d\right)}{G\left(dBi\right)})\\ \end{array}\right.---\left(3\right)$

${\tilde{y}}_i=\frac{\frac{y_{m1}}{d_1+d_2}+\frac{y_{m2}}{d_2+d_3}+...+\frac{y_{mi}}{d_i+d_1}}{\frac{1}{d_1+d_2}+\frac{1}{d_2+d_3}+...+\frac{1}{d_i+d_1}}*(1+\frac{BD\left(d\right)}{G\left(dBi\right)})---\left(4\right)$

Wherein, for the estimation coordinate figure of the mobile terminal of mobile terminal and selected each base station communication; d _ifor the mobile terminal that estimates is to the distance of i-th base station; (x _mi, y _mi) be the coordinate figure of i-th base station.

In step s 103, by the coordinate figure information of the estimation coordinate figure of mobile terminal and each base station with communication of mobile terminal, the mean distance evaluated error between mobile terminal and base station is calculated;

According to an embodiment of the application, the mean distance evaluated error between mobile terminal and base station calculate by following formula (5):

$\stackrel{\‾}{\mathrm{\ϵ}}=\frac{{\mathrm{\Σ}}_{i=1}^n\sqrt{{({\tilde{x}}_i-x_{mi})}^2+{({\tilde{y}}_i-y_{mi})}^2}}{N},(i=1,2...N)---\left(5\right)$

Wherein, for mean distance evaluated error; N is that algorithm performs number of times.

In step S104, according to antenna gain, loss, mean distance estimation error and base station density, calculate the coordinate figure of each mobile terminal;

According to an embodiment of the application, the coordinate figure carrying out the mobile terminal communicated with certain base station calculates by following formula (6) and (7):

$\left\{\begin{array}{c}{X}_i=\frac{G\left(dBi\right)-BD\left(d\right)}{\stackrel{\‾}{\mathrm{\ϵ}}}*DA+x_{mi}---\left(6\right)\\ Y_i=\frac{G\left(dBi\right)-BD\left(d\right)}{\widetilde{\mathrm{\ϵ}}}*DA+y_{mi}---\left(7\right)\end{array}\right.$

Wherein, G (dBi) is antenna gain; BD (d) is the loss of signal in transmitting procedure; for mean distance evaluated error; DA is base station density; (x _mi, y _mi) be the coordinate figure of i-th base station;

Wherein, base station density calculates by following formula (8):

$DA=\left(\frac{AQ}{AQ+NQ}\right)\·100\%$

Wherein, AQ is the quantity of the base station selected; NQ be unselected can with the quantity of the base station of communication of mobile terminal.

In step S105, the coordinate figure of several mobile terminals is sued for peace, more on average, obtain the true coordinate value of mobile terminal;

According to an embodiment of the application, selected in 2.5G wireless network several can to carry out the communication coverage of the base station communicated overlapped with mobile terminal, when mobile terminal receives the signal grouping from N number of different base station, calculate the coordinate carrying out the mobile terminal communicated with each base station respectively, again the coordinate of several mobile terminals obtained is sued for peace, average again, be the true coordinate of mobile terminal, achieve the location to mobile terminal in 2.5G wireless network, following formula (8) specifically can be adopted to calculate the true coordinate (X of mobile terminal _dst, Y _dst):

$(X_{dst},Y_{dst})=(\frac{1}{N}{\mathrm{\Σ}}_{i=1}^N{X}_i,\frac{1}{N}{\mathrm{\Σ}}_{i=1}^N{Y}_i),(i=1,2...N)---\left(8\right)$

Wherein, (X _dst, Y _dst) be the true coordinate value of mobile terminal; (X _i, Y _i) be the coordinate figure carrying out the mobile terminal communicated with each selected base station.

The algorithm realization of location of the present invention in 2.5G wireless network to the accurate location of mobile terminal, change traditional location algorithm and do not consider the loss of signal in transmitting procedure and the gain problem of directional antenna, location sensitivity is high, and be applicable to indoor and outdoor location, range of application is greatly enhanced simultaneously.

Claims (9)

1. based on a location algorithm for the 2.5G wireless network signal profit and loss, it is characterized in that, comprising:

Obtain the antenna gain of mobile terminal and base station Signal transmissions in 2.5G wireless network, and the loss produced in signals transmission;

Select several and mobile terminal in 2.5G wireless network, carry out the base station communicated, the distance between estimation mobile terminal and the base station of each selection; According to the distance value of each estimation, adopt weighted mass center algorithm, obtain the estimation coordinate figure carrying out the mobile terminal communicated with each base station;

By the coordinate figure information of the estimation coordinate figure of described mobile terminal and each base station with described communication of mobile terminal, calculate the mean distance evaluated error between described mobile terminal and base station;

According to antenna gain, the loss of Signal transmissions between described mobile terminal and base station, and mean distance evaluated error and base station density, calculate the coordinate figure carrying out the mobile terminal communicated with each base station;

The coordinate figure of several mobile terminals described is sued for peace, more on average, obtains the true coordinate value of described mobile terminal, realize based on the location to mobile terminal when the profit and loss of 2.5G wireless network signal.

2. the location algorithm based on the profit and loss of 2.5G wireless network signal according to claim 1, is characterized in that, in described acquisition 2.5G wireless network, between mobile terminal and base station, the method for the antenna gain of Signal transmissions is:

Following formulae discovery is adopted to obtain the antenna gain G (dBi) of Signal transmissions between mobile terminal and base station:

G(dBi)＝10lg{50000/(2θ3dB,E×2θ3dB,H)}

Wherein, 2 θ 3dB, E and 2 θ 3dB, H are respectively the lobe width of antenna on two principal planes, and 50000 is the empirical datas counted in 2.5G wireless network.

3. the location algorithm based on the profit and loss of 2.5G wireless network signal according to claim 1, is characterized in that, the method for the loss produced in signals transmission between described acquisition mobile terminal and base station is:

Adopt loss BD (d) that following formulae discovery signal produces in transmitting procedure:

$BD\left(d\right)=\{\stackrel{\‾}{BD}\left(d\right)+5klog\frac{dy}{dx}\}*\mathrm{\β}$

Wherein, BD (d) is the path loss of Signal transmissions after distance d; for the path loss of Signal transmissions after unit distance; K is path interference factor; 5 is the constant numerical value of signal in 2.5G wireless network; Dx is the received power of 2.5G wireless network, and dy is the emissive power of 2.5G wireless network; β is 2.5G wireless network correction constant numerical value, is 1.342.

4. the location algorithm based on the profit and loss of 2.5G wireless network signal according to claim 1, it is characterized in that, the described distance value according to each estimation, adopts weighted mass center algorithm, obtains with the detailed process of the estimation coordinate figure of the mobile terminal of each base station communication being:

Described mobile terminal selects i base station from the base station that can communicate with it, estimates the distance between mobile terminal and each base station, according to each distance value estimated, adopts the estimation coordinate figure of the mobile terminal of following formulae discovery and each base station communication

$\left\{\begin{array}{c}{\tilde{x}}_i=\frac{\frac{x_{m1}}{d_1+d_2}+\frac{x_{m2}}{d_2+d_3}+...+\frac{x_{mi}}{d_i+d_1}}{\frac{1}{d_1+d_2}+\frac{1}{d_2+d_3}+...+\frac{1}{d_i+d_1}}*(1+\frac{BD\left(d\right)}{G\left(dBi\right)})\\ {\tilde{y}}_i=\frac{\frac{y_{m1}}{d_1+d_2}+\frac{y_{m2}}{d_2+d_3}+...+\frac{y_{mi}}{d_i+d_1}}{\frac{1}{d_1+d_2}+\frac{1}{d_2+d_3}+...+\frac{1}{d_i+d_1}}*(1+\frac{BD\left(d\right)}{G\left(dBi\right)})\end{array}\right.$

Wherein, for the estimation coordinate figure of the mobile terminal of mobile terminal and selected each base station communication; d _ifor the mobile terminal that estimates is to the distance of i-th base station; (x _mi, y _mi) be the coordinate figure of i-th base station.

5. the location algorithm based on the profit and loss of 2.5G wireless network signal according to claim 1 or 4, it is characterized in that, by the coordinate figure information of the estimation coordinate figure of described mobile terminal and each base station with described communication of mobile terminal, the method calculating the mean distance evaluated error between described mobile terminal and base station is:

Adopt the mean distance evaluated error between following formulae discovery mobile terminal and base station

$\stackrel{\‾}{\mathrm{\ϵ}}=\frac{{\mathrm{\Σ}}_{i=1}^n\sqrt{{({\tilde{x}}_i-x_{mi})}^2+{({\tilde{y}}_i-y_{mi})}^2}}{N},(i=1,2...N)$

Wherein, for mean distance evaluated error; N is that algorithm performs number of times.

6. the location algorithm based on the profit and loss of 2.5G wireless network signal according to claim 1, it is characterized in that, according to antenna gain, the loss of Signal transmissions between described mobile terminal and base station, and mean distance evaluated error and base station density, calculating the method for carrying out the coordinate figure of the mobile terminal communicated with each base station is:

Coordinate figure (the X of the mobile terminal communicated is carried out by following formulae discovery and certain base station _i, Y _i):

$\left\{\begin{array}{c}{X}_i=\frac{G\left(dBi\right)-BD\left(d\right)}{\stackrel{\‾}{\mathrm{\ϵ}}}*DA+x_{mi}\\ Y_i=\frac{G\left(dBi\right)-BD\left(d\right)}{\widetilde{\mathrm{\ϵ}}}*DA+y_{mi}\end{array}\right.$

Wherein, G (dBi) is antenna gain; BD (d) is the loss of signal in transmitting procedure; for mean distance evaluated error; DA is base station density; (x _mi, y _mi) be the coordinate figure of i-th base station.

7. the location algorithm based on the profit and loss of 2.5G wireless network signal according to claim 6, is characterized in that, described base station density is obtained by following formulae discovery:

$DA=\left(\frac{AQ}{AQ+NQ}\right)\·100\%$

Wherein, AQ is the quantity of the base station selected; NQ be unselected can with the quantity of the base station of communication of mobile terminal.

8. the location algorithm based on the profit and loss of 2.5G wireless network signal according to claim 1, is characterized in that, sues for peace to the coordinate figure of several mobile terminals described, more on average, the method obtaining the true coordinate value of described mobile terminal is:

By the true coordinate (X of following formulae discovery mobile terminal _dst, Y _dst):

$(X_{dst},Y_{dst})=(\frac{1}{N}{\mathrm{\Σ}}_{i=1}^N{X}_i,\frac{1}{N}{\mathrm{\Σ}}_{i=1}^N{Y}_i),(i=1,2...N)$

Wherein, (X _dst, Y _dst) be the true coordinate value of mobile terminal; (X _i, Y _i) be the coordinate figure carrying out the mobile terminal communicated with each selected base station.

9. the location algorithm based on the profit and loss of 2.5G wireless network signal according to claim 1, is characterized in that, the loss that described signal produces in transmitting procedure produced by the impact of weather or barrier.