CN103024898A - ZigBee technology positioning method based on received signal strength indicator (RSSI) and received signal strength (RSS) - Google Patents

Abstract

The invention discloses a ZigBee technology positioning method based on a received signal strength indicator (RSSI) and received signal strength (RSS). The method is particularly suitable for emergency processing of emergencies, for example, when the emergencies occur, trapped people can be accurately positioned, and timely saving of the trapped people can be facilitated. On the basis of existing positioning algorithms based on ZigBee, the ZigBee technology positioning method based on the RSSI and the RSS is provided. The method includes received power pRX calculation, RSS calculation, coordinate calculation of a locating tag node M, weight based locating process, calculation of average weight of each base station node, calculation of weight of base station nodes and the locating tag node, and obtaining the coordinate of the locating tag node M. The ZigBee technology positioning method based on the RSSI and the RSS has the advantages of being high in positioning accuracy and good in applicability.

Description

A kind of ZigBee technology localization method based on RSSI and RSS

Technical field

The present invention relates to short-distance wireless communication technology, position etc. the knowledge in field based on signal strength signal intensity indication (RSSI), especially a kind of ZigBee technology localization method.

Background technology

Along with the continuous propelling of coal mining, underground work casualties number is also constantly rising.Although country has carried forward vigorously the improvement of mine safety measure, but mine accident still happens occasionally, and because the mine production environment is abominable, type complicated, mobility of people is large, so that search and rescue weak effect, the efficient of rescue and relief work, safety first-aid is low, so how when mine accident occurs, in time navigate to the accurate location of indicator of trapped personnel and sue and labour and just seem particularly important.ZigBee technology is as a kind of emerging short-distance wireless communication technology, because the superiority such as its low cost, low-power consumption, low-complexity, carry out personnel positioning in the down-hole of circumstance complication and have clearly advantage, thereby in underground communica tion, obtained a large amount of application.

Location algorithm based on ZigBee technology refers to that the mine staff carries positioning label, positioning label constantly sends its information of carrying near base station by the frequency of appointment, base-station node reads carry information and the signal strength indication value of each positioning label automatically, according to the relation of signal strength signal intensity indication (RSSI) with distance, calculate the position at underground work personnel place.Weights-selected Algorithm is to solve positioning accuracy problem on the low side is arranged under the environment such as barrier, electromagnetism, refraction.The signal strength signal intensity indication that now utilizes base-station node to read, the research of a kind of new algorithm of the location of finding range.Right to use value function combines to locate with RSS in algorithm, can improve positioning accuracy in complex environment.

Location algorithm has a variety of, the main location algorithm of two large classes is arranged now, be respectively RFID and ZigBee, but location algorithm can there be a lot of different classification according to different standards, wherein method relatively commonly used is location, three limits, and this also is the basis of the localization method that adopts of the present invention.In a two-dimensional coordinate system, minimum needs are used the unique coordinate of determining a point of distance ability of three reference points.Wireless location technology develops out some reasonable methods on the basis of three limits location: based on the location of ranging technology with need not the location of ranging technology.Location based on ranging technology mainly contains TOA, TDOA, AOA, signal strength signal intensity telemetry; The location algorithm that need not to find range mainly contains: the algorithm of centroid method, convex programming location algorithm, distance vector jumping figure.

There are a lot of accidentalia in location algorithm based on RFID, and can only be accurate to certain scope, and positioning accuracy is relatively poor; ZigBee technology, is widely applied in underground communica tion, particularly the personnel location system in the complex environment of down-hole with superiority such as its low-power consumption, low cost, low-complexities as a kind of emerging short-distance wireless communication technology.But existing location algorithm based on ZigBee can only could navigate to higher precision concrete point in the situation that environment is relatively more spacious, in case be in the complex environment, positioning accuracy is just relatively low.

Summary of the invention

In order to overcome the deficiency that positioning accuracy is relatively poor, applicability is relatively poor that has based on the localization method of ZigBee technology, the invention provides the ZigBee technology localization method based on RSSI and RSS that a kind of positioning accuracy is higher, applicability is good.

The technical solution adopted for the present invention to solve the technical problems is:

A kind of ZigBee technology localization method based on RSSI and RSS may further comprise the steps:

1) received power p _RXCalculating: wherein RSSI is received signal strength indicator, p _RefBe transmission power level, the pass between the three is:

$\mathrm{RSSI}=10\×\log \frac{p_{\mathrm{RX}}}{p_{\mathrm{Ref}}}---\left(1\right)$

P wherein _Ref=1mW;

2) calculating of RSS: RSS constructs according to the relation of transmitting terminal transmitting power and received power, and wherein transmitting power is tried to achieve by formula (1);

3) coordinate Calculation of positioning label node M: make any 3 base-station node J ₁, J ₂, J ₃Node coordinate be (x ₁, y ₁), (x ₂, y ₂), (x ₃, y ₃), the coordinate of positioning label node is (x, y), then can obtain:

$d_{1M}=\sqrt{{(x_1-x)}^2+{(y_1-y)}^2}---\left(2\right)$

$d_{2M}=\sqrt{{(x_2-x)}^2+{(y_2-y)}^2}---\left(3\right)$

$d_{3M}\sqrt{{(x_3-x)}^2+{(y_3-y)}^2}---\left(4\right)$

D wherein _1M, d _2M, d _3MRepresent respectively base-station node J ₁, J ₂, J ₃Distance with destination node M;

4) based on the weights position fixing process: positioning label is the base-station node transmitted signal towards periphery, has 3 base-station nodes in this scope at least, receives signal in the situation that determine at least 3 base stations, makes these 3 base-station nodes be respectively _J1, J ₂, J ₃, positioning label receives 3 different automatic-answering back device signals, the position of calculating label node M, and wherein, the position of each base-station node immobilizes, and the distance between the adjacent base station node is constant, and then the weights equation between the base-station node is:

$W_{12}=\frac{d_{12}}{{\mathrm{RSS}}_{12}}\×100---\left(5\right)$

$W_{13}=\frac{d_{13}}{{\mathrm{RSS}}_{13}}\×100---\left(6\right)$

$W_{23}=\frac{d_{23}}{{\mathrm{RSS}}_{23}}\×100---\left(7\right)$

W wherein ₁₂, W ₁₃, W ₂₃Represent respectively base-station node J ₁And J ₂, base-station node J ₁And J ₃, base-station node J ₂And J ₃Weights; d ₁₂, d ₁₃, d ₂₃Represent respectively base-station node J ₁And J ₂, base-station node J ₁And J ₃, base-station node J ₂And J ₃Between distance; RSS ₁₂, RSS ₁₃, RSS ₂₃Represent respectively base-station node J ₁And J ₂, base-station node J ₁And J ₃, base-station node J ₂And J ₃Between signal strength values;

5) calculating of the average weights of each base-station node: can be drawn the weights of the base-station node that each base-station node is adjacent by formula (4), (5), (6), thereby try to achieve the evaluation weights of each base-station node:

${\mathrm{Avew}J}_1=\frac{\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{W}_{1i}}{N-1}=\frac{W_{12}+W_{13}+...+W_{1N}}{N-1},(N\≥3,i\≠1)---\left(8\right)$

${\mathrm{Avew}J}_2=\frac{\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{W}_{2i}}{N-1}=\frac{W_{21}+W_{23}+...+W_{2N}}{N-1},(N\≥3,i\≠2)---\left(9\right)$

${\mathrm{Avew}J}_3=\frac{\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{W}_{3i}}{N-1}=\frac{W_{31}+W_{32}+...+W_{3N}}{N-1},(N\≥3,i\≠3)---\left(10\right)$

AvewJ wherein ₁, AvewJ ₂, AvewJ ₃Represent respectively base-station node J ₁, J ₂, J ₃Average mean, namely represent base-station node J ₁, J ₂, J ₃Residing main environment;

6) weights of base-station node and positioning label node calculate: the weights equation of base-station node and positioning label node is:

$d_{1M}=\frac{{\mathrm{AvewJ}}_1\×{\mathrm{RSS}}_{1M}}{100}---\left(11\right)$

$d_{2M}=\frac{{\mathrm{AvewJ}}_2\×{\mathrm{RSS}}_{2M}}{100}---\left(12\right)$

$d_{3M}=\frac{{\mathrm{AvewJ}}_3\×{\mathrm{RSS}}_{3M}}{100}---\left(13\right)$

D wherein _1M, d _2M, d _3MRepresent that respectively the positioning label node M is to base-station node J ₁, J ₂, J ₃Distance; RSS _1M, RSS _2M, RSS _3MRepresent respectively base-station node J ₁, J ₂, J ₃And the signal strength values between the positioning label node M;

7) according to formula (11), (12), (13) and formula (2), (3), (4), try to achieve the coordinate (x, y) of positioning label node M.

Technical conceive of the present invention is: the present invention is on the basis of original algorithm, a kind of new ZigBee technology localization method based on RSSI and RSS has been proposed, this algorithm is a kind of weights location algorithm, for solve the mine production environment abominable, complicated, the large such challenge of mobility of people of type have preferably effect.

Beneficial effect of the present invention is mainly manifested in: effectively overcome the drawback that existing ZigBee location algorithm can only could navigate to higher precision in the relatively more spacious situation of environment concrete point, had good effect for the orientation problem that solves under the complicated Minepit environment.

Description of drawings

Fig. 1 is positioning label and the base station weights graph of a relation of the inventive method.

Fig. 2 is the ZigBee technology localization method flow chart based on RSSI and RSS of the inventive method.

Embodiment

The invention will be further described below in conjunction with accompanying drawing.

See figures.1.and.2, a kind of ZigBee technology localization method based on RSSI and RSS may further comprise the steps:

1) received power p _RXCalculating: wherein RSSI is received signal strength indicator, p _RefBe transmission power level, the pass between the three is:

$\mathrm{RSSI}=10\×\log \frac{p_{\mathrm{RX}}}{p_{\mathrm{Ref}}}---\left(1\right)$

P wherein _Ref=1mW;

2) calculating of RSS: RSS constructs according to the relation of transmitting terminal transmitting power and received power, wherein transmitting power by formula (1) can in the hope of;

3) coordinate Calculation of positioning label node M: make any 3 base-station node J ₁, J ₂, J ₃Node coordinate be (x ₁, y ₁), (x ₂, y ₂), (x ₃, y ₃), the coordinate of positioning label node is (x, y), then can obtain:

$d_{1M}=\sqrt{{(x_1-x)}^2+{(y_1-y)}^2}---\left(2\right)$

$d_{2M}=\sqrt{{(x_2-x)}^2+{(y_2-y)}^2}---\left(3\right)$

$d_{3M}\sqrt{{(x_3-x)}^2+{(y_3-y)}^2}---\left(4\right)$

D wherein _1M, d _2M, d _3MRepresent respectively base-station node J ₁, J ₂, J ₃Distance with destination node M;

4) based on the weights location algorithm: the weights location is a kind of algorithm of locating uncertain node based on known several nodes.Positioning label is the base-station node transmitted signal towards periphery, has 3 base-station nodes in this scope at least, receives signal in the situation that determine at least 3 base stations, makes these 3 base-station nodes be respectively J ₁, J ₂, J ₃(positioning label receives 3 different automatic-answering back device signals), the position of calculating label node M, schematic diagram is as shown in Figure 1.Wherein, the position of each base-station node immobilizes, and the distance between the adjacent base station node is constant, and then the weights equation between the base-station node is:

$W_{12}=\frac{d_{12}}{{\mathrm{RSS}}_{12}}\×100---\left(5\right)$

$W_{13}=\frac{d_{13}}{{\mathrm{RSS}}_{13}}\×100---\left(6\right)$

$W_{23}=\frac{d_{23}}{{\mathrm{RSS}}_{23}}\×100---\left(7\right)$

W wherein ₁₂, W ₁₃, W ₂₃Represent respectively base-station node J ₁And J ₂, base-station node J ₁And J ₂, base-station node J ₂And J ₃Weights; d ₁₂, d ₁₃, d ₂₃Represent respectively base-station node J ₁And J ₂, base-station node J ₁And J ₃, base-station node J ₂And J ₃Between distance; RSS ₁₂, RSS ₁₃, RSS ₂₃Represent respectively base-station node J ₁And J ₂, base-station node J ₁And J ₃, base-station node J ₂And J ₃Between signal strength values;

5) calculating of the average weights of each base-station node: can be drawn the weights of the base-station node that each base-station node is adjacent by formula (4), (5), (6), thereby can try to achieve the evaluation weights of each base-station node:

${\mathrm{Avew}J}_1=\frac{\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{W}_{1i}}{N-1}=\frac{W_{12}+W_{13}+...+W_{1N}}{N-1},(N\≥3,i\≠1)---\left(8\right)$

${\mathrm{Avew}J}_2=\frac{\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{W}_{2i}}{N-1}=\frac{W_{21}+W_{23}+...+W_{2N}}{N-1},(N\≥3,i\≠2)---\left(9\right)$

${\mathrm{Avew}J}_3=\frac{\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{W}_{3i}}{N-1}=\frac{W_{31}+W_{32}+...+W_{3N}}{N-1},(N\≥3,i\≠3)---\left(10\right)$

AvewJ wherein ₁, AvewJ ₂, AvewJ ₃Represent respectively base-station node J ₁, J ₂, J ₃Average mean, namely represent base-station node J ₁, J ₂, J ₃Residing main environment;

6) weights of base-station node and positioning label node calculate: the weights equation of base-station node and positioning label node is:

$d_{1M}=\frac{{\mathrm{AvewJ}}_1\×{\mathrm{RSS}}_{1M}}{100}---\left(11\right)$

$d_{2M}=\frac{{\mathrm{AvewJ}}_2\×{\mathrm{RSS}}_{2M}}{100}---\left(12\right)$

$d_{3M}=\frac{{\mathrm{AvewJ}}_3\×{\mathrm{RSS}}_{3M}}{100}---\left(13\right)$

D wherein _1M, d _2M, d _3MRepresent that respectively the positioning label node M is to base-station node J ₁, J ₂, J ₃Distance; RSS _1M, RSS _2M, RSS _3MRepresent respectively base-station node J ₁, J ₂, J ₃And the signal strength values between the positioning label node M;

7) according to formula (11), (12), (13) and formula (2), (3), (4), try to achieve the coordinate (x, y) of positioning label node M;

Claims (1)

1. ZigBee technology localization method based on RSSI and RSS is characterized in that: may further comprise the steps:

1) received power p _RXCalculating: wherein RSSI is received signal strength indicator, p _RefBe transmission power level, the pass between the three is:

P wherein _Ref=1mW;

2) calculating of RSS: RSS constructs according to the relation of transmitting terminal transmitting power and received power, and wherein transmitting power is tried to achieve by formula (1);

3) coordinate Calculation of positioning label node M: make any 3 base-station node J ₁, J ₂, J ₃Node coordinate be (x ₁, y ₁), (x ₂, y ₂), (x ₃, y ₃), the coordinate of positioning label node is (x, y), then can obtain:

D wherein _1M, d _2M, d _3MRepresent respectively base-station node J ₁, J ₂, J ₃Distance with destination node M;

4) based on the weights position fixing process: positioning label is the base-station node transmitted signal towards periphery, has 3 base-station nodes in this scope at least, receives signal in the situation that determine at least 3 base stations, makes these 3 base-station nodes be respectively J ₁, J ₂, J ₃, positioning label receives 3 different automatic-answering back device signals, the position of calculating label node M, and wherein, the position of each base-station node immobilizes, and the distance between the adjacent base station node is constant, and then the weights equation between the base-station node is:

W wherein ₁₂, W ₁₃, W ₂₃Represent respectively base-station node J ₁And J ₂, base-station node J ₁And J ₃, base-station node J ₂And J ₃Weights; d ₁₂, d ₁₃, d ₂₃Represent respectively base-station node J ₁And J ₂, base-station node J ₁And J ₃, base-station node J ₂And J ₃Between distance; RSS ₁₂, RSS ₁₃, RSS ₂₃Represent respectively base-station node J ₁And J ₂, base-station node J ₁And J ₃, base-station node J ₂And J ₃Between signal strength values;

5) calculating of the average weights of each base-station node: can be drawn the weights of the base-station node that each base-station node is adjacent by formula (4), (5), (6), thereby try to achieve the evaluation weights of each base-station node:

AvewJ wherein ₁, AvewJ ₂, AvewJ ₃Represent respectively base-station node J ₁, J ₂, J ₃Average mean, namely represent base-station node J ₁, J ₂, J ₃Residing main environment;

6) weights of base-station node and positioning label node calculate: the weights equation of base-station node and positioning label node is:

D wherein _1M, d _2M, d _3MRepresent that respectively the positioning label node M is to base-station node J ₁, J ₂, J ₃Distance; RSS _1M, RSS _2M, RSS _3MRepresent respectively base-station node J ₁, J ₂, J ₃And the signal strength values between the positioning label node M;

7) according to formula (11), (12), (13) and formula (2), (3), (4), try to achieve the coordinate (x, y) of positioning label node M.

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