CN104581937A - Node positioning method based on RSSI (received signal strength indicator) - Google Patents

Node positioning method based on RSSI (received signal strength indicator) Download PDF

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Publication number
CN104581937A
CN104581937A CN201410834896.3A CN201410834896A CN104581937A CN 104581937 A CN104581937 A CN 104581937A CN 201410834896 A CN201410834896 A CN 201410834896A CN 104581937 A CN104581937 A CN 104581937A
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CN
China
Prior art keywords
node
datum
rssi
destination node
destination
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CN201410834896.3A
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Chinese (zh)
Inventor
吴庆九
吕晓敏
琚春华
黄治移
谷同魁
鲍福光
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QWARE TECHNOLOGY GROUP Co Ltd
Zhejiang Gongshang University
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QWARE TECHNOLOGY GROUP Co Ltd
Zhejiang Gongshang University
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Priority to CN201410834896.3A priority Critical patent/CN104581937A/en
Publication of CN104581937A publication Critical patent/CN104581937A/en
Pending legal-status Critical Current

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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
    • H04W64/003—Locating users or terminals or network equipment for network management purposes, e.g. mobility management locating network equipment
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/18—Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

The invention relates to the field of wireless network data transmission and discloses a node positioning method based on an RSSI (received signal strength indicator). Reference nodes and target nodes are used in the method. In order to realize node positioning, the method comprises the following specific steps: calculating a distance d, related with the RSSI value of each reference node, between each reference node and each target node; determining the number of the reference nodes related with the target nodes and performing positioning based on the number of the reference nodes; during positioning, establishing at least one mapping between the target node and the reference node, wherein the mapping at least comprises the target node obtained based on the position of the reference node, the reference node and the distance, related with the RSSI value of the reference node, between the reference node and the target node or position information; and positioning the target node based on the mapping. The node positioning method has the advantages that a problem in calculation of a node position of any target node can be really solved, and the node position can be further corrected, so that the positioning accuracy is improved.

Description

Based on the node positioning method of RSSI
Technical field
The present invention relates to wireless network data transmission field, particularly a kind of node positioning method based on RSSI, be particularly useful for the transmission usefulness of the transfer of data improving wireless network.
Background technology
Wireless sensor network (Wireless Sensor Networks) gets up to form network based on wireless communication means, by the sensor node link being used for monitoring target thing, is the main foundation technology promoting Internet of Things development.Wireless sensor technology is considered to the technology that 21 century can play a significant role to information technology, economy and social progress.
Usually, wireless sensor network is made up of the node of many oriented missions, and these nodes have data acquisition, data processing and data-transformation facility, and can realize MANET in certain scale, scope.This network carries out real time data monitoring, real time data processing, real-time Data Transmission by sensor node to target information, and by cordless communication network or other forms of data transmission network, Monitoring Data is sent to far-end control centre.Wireless sensor technology improves the ability of people to acquisition of information, achieving people whenever and wherever possible can the hope of obtaining information, wireless sensor technology has the advantages such as construction cost is low, node is laid flexibly, information Perception scope is wide, network high reliability, and oneself is through being widely used in the fields such as family, military affairs, agricultural, industry, logistics, environmental monitoring, mine safety monitoring and traffic administration.
The research of wireless sensor node location algorithm is one of key technology improving data transmission efficiency.First, because in most cases only have the data of positional information just valuable, the data that transducer collects must be combined with the position of transducer; Secondly, had relatively accurate node location, respective nodes just likely selects a route uploading data easily.To this,
Summary of the invention
The present invention is directed in prior art and lack the shortcoming that a kind of data provided by network node itself obtain arbitrary node positional information, provide a kind of node positioning method based on RSSI, by obtaining the RSSI value of datum node, and positional information, thus realize the object of computing node position.
For achieving the above object, the present invention can take following technical proposals:
Based on a node positioning method of RSSI, comprise datum node and destination node, described datum node is can as the definition base of the logic of destination node and/or physical location and its position can by the arbitrary node known in advance;
In order to realize node locating, also comprise following concrete steps:
Calculation Basis node and the distance d relevant with the RSSI value of datum node between destination node; RSSI value produces after the filtering of backward channel Baseband Receiver, carries out the instantaneous value that baseband I/Q branch power integration obtains RSSI in 104 μ s, and is averaged to instantaneous value in 1s and obtains the mean value of RSSI.
Determine the quantity of the datum node relevant to destination node and position in this, as prerequisite;
During location, between described destination node and datum node, set up at least one map, described mapping at least should comprise destination node, datum node and the distance relevant with the RSSI value of datum node between destination node to datum node or positional information that can be obtained by the position of datum node;
Position according to above-mentioned mapping pair destination node.
In the embodiment of the application, distance d should be calculated in confirmable finding range in advance being no more than.
In the embodiment of the application, described distance wherein a, b be one can predetermined fixed numbers.
In the embodiment of the application, also comprise the range finding correction value x ' described distance d being carried out to error compensation i, x represents the actual range of datum node and destination node.
In the embodiment of the application, described range finding correction value wherein, i represents sequence number or the identifier of a series of datum nodes relevant to destination node, x irepresent the actual range between destination node and datum node, represent the error between destination node and datum node; x iwith between at least meet following relation wherein
In the embodiment of the application, also comprise following location algorithm: destination node periodically records the RSSI average of at least one datum node; According to RSSI average is descending, datum node is sorted; Set up the mapping between destination node and datum node, described mapping at least comprises following three set: the distance set beacon_set={a between datum node 1, a 2..., a m, the distance set Dis_set={d between destination node and datum node 1, d 2..., d mand datum node between location sets Pos_set={ (X 1, Y 1), (X 2, Y 2) ..., (X m, Y m), wherein m represents the quantity of datum node; The position (X, Y) of destination node is X = Σ i = 1 m X i d i Σ i = 1 m 1 d i , Y = Σ i = 1 m Y i d i Σ i = 1 m 1 d i .
In the embodiment of the application, calculate the position (X of mark node, Y) time, the quantity of the actual datum node used should not exceed the quantity that can record the datum node of RSSI value at destination node, and the quantity of the actual datum node used can be recorded by destination node in the datum node of RSSI value to be chosen.
In the embodiment of the application, when calculating position (X, the Y) of mark node, at least one datum node that the RSSI average that the actual datum node used records for destination node is maximum.Particularly, choose the maximum n of a RSSI average datum node in m datum node, according to above-mentioned location algorithm, after n benchmark economize on electricity sequence, set up and map, the position (X, Y) of destination node is
In the embodiment of the application, also comprise following concrete steps: when positioning, should determine that the quantity of an interior datum node of skipping a grade is not less than three.
In the embodiment of the application, when the quantity of an interior datum node of skipping a grade is less than three, also comprise following concrete steps: calculate the minimum hop count between destination node and each datum node respectively; Calculate the actual jumping segment distance between destination node and each datum node respectively wherein, (x i, y i), (x j, y j) be followed successively by the coordinate of datum node i, j, h respectively jfor the jumping figure between datum node i, j; Described reality is jumped segment distance HopSize and is distributed in network by datum node, after target node accepts jumps segment distance HopSize to described reality, according to the jumping figure of record, calculate the jumping segment distance of destination node to each datum node, thus obtain the distance of destination node and datum node.
The present invention has following remarkable technique effect:
More adequately can calculate the position of arbitrary node, depend on the density of anchor node simultaneously and realized the accuracy of position by corrected Calculation, there is good using value.
Accompanying drawing explanation
Fig. 1 is the structural representation of position between node.
Fig. 2 is the roughly schematic flow sheet of the node positioning method based on RSSI.
Embodiment
Below in conjunction with embodiment, the present invention is described in further detail.
Embodiment 1
A kind of node positioning method based on RSSI, as shown in Figure 1, 2, comprise datum node 100 and destination node 200, described datum node 100 is can as the definition base of the logic of destination node 200 and/or physical location and its position can by the arbitrary node known in advance, described datum node 100 is a kind of special joint being called as anchor node, and datum node 100 sends specifically about the information ((x of self-position i, y i), RSSI i), by arrange in advance or by means such as pre-configured gps receivers, destination node can receive the information ((x about self-position that said reference node 100 sends i, y i), RSSI i), and it can be used as the foundation of self poisoning.The quantity of datum node 100 can have multiple, and in order to improve computational accuracy, can be able to receive in the scope of signal at destination node 200, multiselect gets the quantity of datum node 100 as much as possible.Namely destination node 200 needs the node positioned.
Further, in order to realize node locating, also comprise following concrete steps:
The distance d relevant with the RSSI value of datum node 100 between Calculation Basis node 100 to destination node 200; If destination node 200 can receive the signal of multiple datum node 100, then need to calculate distance d respectively.
Determine the quantity of the datum node 100 relevant to destination node 200 and position in this, as prerequisite;
During location, between described destination node 200 and datum node 100, set up at least one map, described mapping at least should comprise destination node 200, datum node 100 and the distance relevant with the RSSI value of datum node 100 between destination node 200 to datum node 100 or positional information that can be obtained by the position of datum node 100;
Position according to above-mentioned mapping pair destination node 200.
Distance d should be calculated in confirmable finding range in advance being no more than.Typically, limiting finding range radius around destination node 200 is within 14m, and by following formulae discovery distance d.
Distance wherein a, b be one can predetermined fixed numbers.As the preferred scheme of one, the value that wherein a can choose is the value that 54.67, b can choose is 2.37, and above-mentioned value can adjust along with concrete situation, and those skilled in the art can determine other value according to specific needs.
Further, in order to the computational accuracy of distance d can be improved, also comprise the range finding correction value x ' described distance d being carried out to error compensation i, for corrected range d, wherein, x represents the actual range of datum node 100 and destination node 200.
Described range finding correction value wherein, i represents sequence number or the identifier of a series of datum nodes 100 relevant to destination node 200, to be that the size of RSSI average received by destination node 200 is descending choose at least one larger datum node 100, x of RSSI average for optional scheme irepresent the actual range between destination node 200 and datum node 100, represent the error between destination node 200 and datum node 100; x iwith between at least meet following relation namely wherein,
Further, in order to can more accurately position destination node 200, as the optional scheme of one, determining the position of destination node 200, namely in process destination node 200 positioned, also comprise following location algorithm: destination node 200 periodically records the RSSI average of at least one datum node 100, because datum node periodically sends self information, this self information comprises node ID, the information such as position, therefore also can be called beacon or beaconing nodes by these datum nodes 100 in the present embodiment.In the information that target node accepts is sent to a datum node, such as, about the information ((x of self-position i, y i), RSSI i) time, destination node 200 records respectively and calculates the RSSI average of each datum node 100, this RSSI average can obtain according to the scrutable mode of those skilled in the art, such as, by calculating in a period of time the mean value of several RSSI value that obtains or the average of other types obtains, according to RSSI average is descending, datum node 100 is sorted, further, as the optional scheme of one, the quantity of datum node 100 should be limited, but destination node 200 finds the quantity that can receive the datum node 100 of information and to reach or beyond after predetermined datum node 100 amount threshold, the scheme that can take is, at once above-mentioned sequence is carried out to the existing datum node 100 having received information, certainly, also other similar schemes can be taked, such as stop the information etc. that the new datum node 100 of reception is sent, those skilled in the art can replace accordingly according to technique scheme.Set up the mapping between destination node 200 and datum node 100, described mapping at least comprises following three set: the distance set beacon_set={a between datum node 100 1, a 2..., a m, the distance set Dis_set={d between destination node 200 and datum node 100 1, d 2..., d mand datum node 100 between location sets Pos_set={ (X 1, Y 1), (X 2, Y 2) ..., (X m, Y m), wherein m represents the quantity of datum node 100; The position (X, Y) of destination node is it should be pointed out that the quantity of above-mentioned mapping is relevant to the quantity of datum node 100, if there are three datum nodes 100, then should comprise three data in each set mapped.
Calculate the position (X of mark node, Y) time, the quantity of the actual datum node 100 used should not exceed the quantity that can record the datum node 100 of RSSI value at destination node 200, and the quantity of the actual datum node 100 used can be recorded by destination node 200 in the datum node 100 of RSSI value to be chosen.As the optional scheme of one, when calculating position (X, the Y) of mark node, at least one datum node 100 that the RSSI average that the actual datum node 100 used records for destination node 200 is maximum.
Further, when positioning calculating, also need to consider that the quantity of datum node 100 is for the impact of destination node 200 positioning precision, comprises following concrete steps: when positioning, should determine that the quantity of an interior datum node 100 of skipping a grade is not less than three.
Further, when the quantity of an interior datum node 100 of skipping a grade is less than three, or when the computational accuracy of destination node 200 being caused to decline arbitrarily, such as, the quantity of a datum node of skipping a grade interior 100 reduces until when being less than three, also comprises following concrete steps:
First, calculate the minimum hop count between destination node and each datum node 100 respectively, datum node 100, or be called that beaconing nodes is to the arbitrary node that can receive its locating information, neighbor node is called as in the present embodiment, the grouping of broadcast own location information, comprising hop count field, be initialized as 0, further, receiving node record has the minimum hop count to each beaconing nodes, ignores the grouping of the larger jumping figure from same beaconing nodes, then jumping figure value is added 1, and be transmitted to the neighbor node of this recipient node.By this method, all nodes in network can record the minimum hop count of each beaconing nodes.
Secondly, calculate the actual jumping segment distance HopSize between destination node 200 and each datum node 100 respectively, each beaconing nodes, according to the positional information of other beaconing nodes recorded in first stage with at a distance of jumping figure, estimates the actual range HopSize on average often jumped.Actual jumping segment distance wherein, (x i, y i), (x j, y j) be followed successively by the coordinate of datum node i, j, h respectively jfor the jumping figure between datum node i, j; Described reality is jumped segment distance HopSize and is distributed in network by datum node 100, specifically, beaconing nodes often jumps average distance with the multicasting with lifetime field in network by what calculate, unknown node only records first of receiving and often jumps average distance, and be transmitted to neighbor node, after destination node 200 receives described reality jumping segment distance HopSize, according to the jumping figure of record, calculate the jumping segment distance of destination node 200 to each datum node 100, thus obtain the distance of destination node 200 and datum node 100.
In a word, the foregoing is only preferred embodiment of the present invention, all equalizations done according to the present patent application the scope of the claims change and modify, and all should belong to the covering scope of patent of the present invention.

Claims (10)

1. the node positioning method based on RSSI, it is characterized in that, comprise datum node (100) and destination node (200), described datum node (100) is can as the definition base of the logic of destination node (200) and/or physical location and its position can by the arbitrary node known in advance;
In order to realize node locating, also comprise following concrete steps:
The distance d relevant with the RSSI value of datum node (100) between Calculation Basis node (100) to destination node (200);
Determine the quantity of the datum node (100) relevant to destination node (200) and position in this, as prerequisite;
During location, between described destination node (200) and datum node (100), set up at least one map, described mapping at least should comprise destination node (200), datum node (100) and the distance relevant with the RSSI value of datum node (100) between destination node (200) to datum node (100) or positional information that can be obtained by the position of datum node (100); Position according to above-mentioned mapping pair destination node (200).
2. the node positioning method based on RSSI according to claim 1, is characterized in that, should calculate distance d in confirmable finding range in advance being no more than.
3. the node positioning method based on RSSI according to claims 1 or 2, is characterized in that, described distance wherein a, b be one can predetermined fixed numbers.
4. the node positioning method based on RSSI according to claim 1, is characterized in that, also comprises the range finding correction value x ' described distance d being carried out to error compensation i, x represents the actual range of datum node (100) and destination node (200).
5. the node positioning method based on RSSI according to claim 4, is characterized in that, described range finding correction value wherein, i represents sequence number or the identifier of a series of datum nodes (100) relevant to destination node (200), x irepresent the actual range between destination node (200) and datum node (100), represent the error between destination node (200) and datum node (100); x iwith between at least meet following relation wherein
6. the node positioning method based on RSSI according to claim 1, is characterized in that, also comprises following location algorithm: destination node (200) periodically records the RSSI average of at least one datum node (100); According to RSSI average is descending, datum node (100) is sorted; Set up the mapping between destination node (200) and datum node (100), described mapping at least comprises following three set: the distance set beacon_set={a between datum node (100) 1, a 2..., a m, the distance set Dis_set={d between destination node (200) and datum node (100) 1, d 2..., d mand datum node (100) between location sets Pos_set={ (X 1, Y 1), (X 2, Y 2) ..., (X m, Y m), wherein m represents the quantity of datum node (100); The position (X, Y) of destination node is
7. the node positioning method based on RSSI according to claim 6, it is characterized in that, calculate the position (X of mark node, Y) time, the quantity of the actual datum node (100) used should not exceed the quantity that can record the datum node (100) of RSSI value at destination node (200), and the quantity of the actual datum node (100) used can be recorded by destination node (200) in the datum node (100) of RSSI value to be chosen.
8. the node positioning method based on RSSI according to claim 6 or 7, it is characterized in that, calculate the position (X of mark node, Y) time, at least one datum node (100) that the RSSI average that the actual datum node (100) used records for destination node (200) is maximum.
9. the node positioning method based on RSSI according to claim 1, is characterized in that, also comprises following concrete steps: when positioning, and should determine that the quantity of an interior datum node (100) of skipping a grade is not less than three.
10. the node positioning method based on RSSI according to claim 9, it is characterized in that, when the quantity of an interior datum node (100) of skipping a grade is less than three, also comprise following concrete steps: calculate the minimum hop count between destination node and each datum node (100) respectively; Calculate the actual jumping segment distance between destination node (200) and each datum node (100) respectively wherein, (x i, y i), (x j, y j) be followed successively by the coordinate of datum node i, j, h respectively jfor the jumping figure between datum node i, j; Described reality is jumped segment distance HopSize and is distributed in network by datum node (100), after destination node (200) receives described reality jumping segment distance HopSize, according to the jumping figure of record, calculate the jumping segment distance of destination node (200) to each datum node (100), thus obtain the distance of destination node (200) and datum node (100).
CN201410834896.3A 2014-12-29 2014-12-29 Node positioning method based on RSSI (received signal strength indicator) Pending CN104581937A (en)

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CN105050168A (en) * 2015-06-17 2015-11-11 上海海事大学 Non-range-finding underwater wireless sensor network node positioning method and system
CN106993273A (en) * 2017-03-29 2017-07-28 江南大学 Based on distance weighted and genetic optimization DV Hop localization methods
CN108548533A (en) * 2018-04-25 2018-09-18 山东爱泊客智能科技有限公司 A kind of localization method and positioning device of the anchor node positioned in real time for red point
CN110708463A (en) * 2019-10-09 2020-01-17 Oppo广东移动通信有限公司 Focusing method, focusing device, storage medium and electronic equipment

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CN102083204A (en) * 2010-12-31 2011-06-01 中国科学技术大学苏州研究院 Positioning and tracking system method of active nodes in linear environment
CN102123495A (en) * 2011-01-13 2011-07-13 山东大学 Centroid location algorithm based on RSSI (Received Signal Strength Indication) correction for wireless sensor network
CN102158954A (en) * 2011-02-24 2011-08-17 山东大学 Wireless sensor network positioning algorithm based on nonlinearity optimization
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CN105050168A (en) * 2015-06-17 2015-11-11 上海海事大学 Non-range-finding underwater wireless sensor network node positioning method and system
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CN106993273A (en) * 2017-03-29 2017-07-28 江南大学 Based on distance weighted and genetic optimization DV Hop localization methods
CN108548533A (en) * 2018-04-25 2018-09-18 山东爱泊客智能科技有限公司 A kind of localization method and positioning device of the anchor node positioned in real time for red point
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Application publication date: 20150429