CN104053223A - Low-power wireless sensor network time synchronization method - Google Patents
Low-power wireless sensor network time synchronization method Download PDFInfo
- Publication number
- CN104053223A CN104053223A CN201310090466.0A CN201310090466A CN104053223A CN 104053223 A CN104053223 A CN 104053223A CN 201310090466 A CN201310090466 A CN 201310090466A CN 104053223 A CN104053223 A CN 104053223A
- Authority
- CN
- China
- Prior art keywords
- time
- node
- synchronization
- tar
- synchronous
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
Landscapes
- Mobile Radio Communication Systems (AREA)
- Synchronisation In Digital Transmission Systems (AREA)
Abstract
The invention provides a low-power wireless sensor network time synchronization method. According to the method, synchronization information is carried by a control packet, a timestamp is printed at the tail of the periodic control packet, and a receiver extracts timestamp information and estimates synchronization delay online after receiving a synchronization packet. The receiver calibrates the time thereof according to the principle of time calibration, and realizes a synchronization mechanism for whole-network synchronization through local synchronization. During synchronization, synchronization is performed only between father and son nodes. By adopting the method of the invention, the number of nodes sending time messages in a network can be greatly reduced, the network traffic in the process of synchronization can be reduced, and the goal of reducing the power consumption of wireless sensor network time synchronization can be achieved under the premise of ensuring the time synchronization accuracy.
Description
Technical field
The invention belongs to sensor network technology field, relate to the send mode of synchronization message in wireless sense network, specifically a kind of low energy consumption, high precision wireless Sensor Network method for synchronizing time.
Background technology
Wireless sense network (WSN) forms by being deployed in microsensor nodes a large amount of in monitored area, the multihop self-organizing network forming by communication.The change that it has brought information Perception with low-power consumption, low cost, feature distributed and self-organizing, in environment sensing and monitoring, wireless location and tracking, medical monitoring, the fields such as Smart Home all show application prospect widely.
Time synchronized is a critical support technology of WSN.WSN is a kind of distributed system, and the local clock of each node is separate, and this just causes the system time of each node different.Many WSN application need each node cooperative work, and the initial data of individual node collection needs and unified processing of other node datas just can be obtained useful information.For example in target following application scenarios, need that the data of interdependent node collection are carried out to Kalman filtering and just can extract useful positional information.Suchlike data processing all needs the interdependent node retention time to synchronize with data fusion.On the other hand, time synchronized also has important application at the design aspect of WSN communication protocol.The design object of MAC (Medium Access Protocol) agreement mainly comprises saves energy consumption and the collision of avoiding a conflict, and TDMA has inborn advantage in this respect, and time synchronized is the basis of TDMA.
The system time of sensor node is produced by timer, and timing signal is generally provided by crystal oscillator (crystal oscillator).Because the manufacturing process of crystal oscillator has difference, running environment changes, and toggle rate is difficult to be consistent, and causes the time of each node to be easy to lose synchronously.Therefore need to design the time synchronized that special synchronized algorithm guarantees nodes.
Traditional method for synchronizing time mainly contains NTP (Network Time Protocol) and GPS (Global Positioning System).NTP is the standard time synchronous protocol on Internet, is mainly All hosts in the Internet standard UTC (the Coordinated Universal Time) time is provided.GPS is used for carrying out global high accuracy Navigation and localization.NTP and GPS need specific equipment or dedicated node could realize synchronously.Because sensor node hardware resource is limited, energy-conservation requirement comparison high all cannot directly be used these two kinds of traditional method for synchronizing time in WSN.
Method for synchronizing time for WSN is mainly divided into following three kinds at present: (1) method for synchronizing time based on recipient-recipient.RBS (Reference Broadcast Synchronization) for example.(2) the unidirectional method for synchronizing time based on sender-recipient.Typical Representative is DMTS (Delay Measurement Time Synchronization) and FTSP (Flooding Time Synchronization Protocol).(3) the two-way method for synchronizing time based on sender-recipient.For example TPSN (Timing-sync Protocol for Sensor Networks) and LTS (Lightweight Tree-based Synchronization).Take below and adopt LTS algorithm to carry out time synchronized to wireless sense network this to be described in detail as example:
The core missions of LTS lightweight spanning tree synchronized algorithm are to reduce the complexity of synchronized algorithm, and the Jana van Greunen of Ta You University of California Berkeley etc. propose.In some sensor network application, to the required precision of time synchronized, be not very high, the node that simultaneously needs time synchronized may not be all nodes of whole network, so just can use the Time Synchronization Mechanism of simple light weight, by reducing time synchronized frequency and participating in synchronous interstitial content, when meeting synchronization accuracy requirement, reduce communication and the computing cost of node, reduce the energy consumption of network.Analysis list hop node between centralized and distributed two kinds of LTS multi-hop Time synchronization algorithms have been proposed on Time Synchronization Mechanism basis based on transmission-receive mode.
Centralized multi-hop synchronized algorithm is the expansion of the synchronous simple linear of single-hop, and its basic thought is the spanning tree of structure low depth, then take tree root as reference node, carries out successively synchronously step by step to leaf node, finally reaches the whole network synchronous.Root node is by synchronous its neighbours' child node synchronizing process start-up time; Then each child node is synchronizeed with its child node again; So repeatedly, until tree leaf node all by synchronously.This root node also will be initiated synchronous again when needed.In centralized multi-hop synchronized algorithm, root node initialization is synchronous, so node adopts same frequency to weigh synchronously, be proportional to the degree of depth of spanning tree the running time of algorithm, and the spanning tree of optimization has the minimum degree of depth, along all branches, walks abreast and carries out simultaneous operation.Due to the lock in time of the whole network of effect of depth and the trueness error of leaf node of spanning tree, the degree of depth of tree need to be transferred back to root node to allow root node utilize this information when decision is synchronous again.The synchronous communication complexity of multi-hop is relevant to the building method of spanning tree and the degree of depth of tree with precision, and heavy synchronizing frequency is relevant to clock drift and single-hop synchronization accuracy.
In distributed synchronization algorithm, each node determines its lock in time, and this algorithm is not used spanning tree.When node i determines it, need to weigh (by synchronization accuracy, require, determine with jumping figure distance and the clock drift of clock source node) when synchronous, just send synchronization request to nearest with reference to node.Then, must be synchronous before i synchronisation of nodes along all nodes the path from clock source node-to-node i.The advantage of this mechanism is that some nodes may seldom have event forwarding, therefore seldom needs synchronous.Because node has an opportunity to determine the synchronous of it, this has just saved unnecessary synchronization overhead.Meanwhile, by merging synchronization request, reduce the number of asking in same paths, saved resource.
In LTS algorithm, the node in network has been avoided synchronizeing with a plurality of upper layer node, and only synchronizes with its direct father node, has reduced message number and lock in time.This algorithm object is to minimize complexity and reduces energy consumption with this, and precision is general.The running time of algorithm and the degree of depth of tree are proportional, and while therefore having the spanning tree of minimum-depth, convergence time is the shortest, but construct little spanning tree, also need certain calculating and communication overhead.
Summary of the invention
The technical problem to be solved in the present invention is, not sacrificing under the prerequisite of synchronization accuracy, for data acquisition scene, provides a kind of wireless sense network method for synchronizing time of low energy consumption, can effectively reduce the expense of time synchronized, reaches the object that reduces time synchronized energy consumption.
For solving the problems of the technologies described above, the present invention is achieved in that
A, periodic synchronous information send, and utilize BEACON bag (controlling bag) to carry synchronizing information, and timestamp is beaten at periodic BEACON bag bag tail, for carrying out time synchronized between node.BEACON pack arrangement as shown in Figure 1.
B, after recipient receives BEACON bag, can calibrate oneself time according to timestamp information.Timestamp comprises TAR and count information, shows the sending node current system time.
Suppose that node 1 and 2 will realize time synchronized, node 1 is time reference node (father node), and node 2 is for treating synchronization node (child node).Calibrating principle is as follows:
TAR
2＝TAR
1+ΔT (1)
TACCR1
2＝TAR
2+(INTERVAL-TAR
2％INTERVAL) (2)
TAR
1and count
1can directly from sync packet, extract, INTERVAL is constant, therefore only has a unknown quantity Δ T.
Internodal sync packet time delay Δ T in C, On-line Estimation wireless sense network, can be used 3 kinds of methods of estimation:
1, setting examination and rectification method.
2, tracking correction method.
3, minizone correction for mean method.
D, with local synchronization, realize the synchronous synchronization mechanism of the whole network.Described step comprises:
In data acquisition tree, all exchanges data are all to carry out father node-child node centering, each node only with his father's synchronisation of nodes, the whole network of realizing step by step by tree topology is synchronous.
1, network can be set up one and take the data acquisition tree that SINK node is root node when initialization.
2, SINK node periodically sends the BEACON bag that comprises timestamp.3, child node parses timestamp after receiving BEACON bag, and according to the clock of formula (1-3) calibration oneself.
4, each node also can be broadcasted BEACON bag according to the mode of SINK node after completing synchronous (that is networking), to facilitate adding of new node.
5, new node adds fashionable can first intercepting a period of time, can choose a father node after collecting the BEACON of neighbor node, and synchronous with it, thereby completes networking.
6, when topology changes, fall the node of net and can first intercept a period of time, reselect father node, and complete synchronous networking.
From said method, can find out, core concept of the present invention is: timestamp is beaten and periodically controlled bag bag tail, by the time synchronized time delay of dynamic estimation father and son node, and utilize the synchronization delayed time of estimating to proofread and correct node time, thereby it is internodal synchronous to realize father and son, reaches and improve the object of wireless sensor network joint timing tracking accuracy and reduce network power consumption.
The present invention has the following advantages:
1, utilize periodically control bag to carry synchronizing information, by synchronizing information being embedded completely in the control bag of upper-layer protocol stack generation, and timestamp is beaten and periodically controlled bag bag tail, sync packet only need be added 9 bytes at the control bag bag tail of MAC layer, just can unify realization synchronously, the function such as route and network operation.。Like this, time synchronized will can not be brought any extra overhead data packet, and just existing packet length is increased to several bytes, can effectively save the energy consumption for time synchronized.
2, by analyzing error distribution character and the time domain variation characteristic of synchronization delayed time, binding time synchronous calibration principle, proposes 3 kinds of synchronization delayed time bearing calibrations: setting examination and rectification method, tracking correction method and minizone correction for mean method.The average of the synchronous error of 3 kinds of synchronization delayed time bearing calibrations and variance have improvement to a certain degree, can reach the synchronization accuracy of Microsecond grade (< 100 microseconds), and its synchronization accuracy and classic algorithm TPSN are suitable with RBS.
3, for market demand scene, propose data acquisition tree, all exchanges data are all to carry out father node-child node centering, each node only with his father's synchronisation of nodes.Utilize tree topology, utilize local father and son's synchronisation of nodes can realize the synchronous of the whole network node, significantly reduced the transmission number of sync packet in network, guaranteeing, under the prerequisite of timing tracking accuracy, effectively to reach the object that can reduce nodes energy consumption.
Accompanying drawing explanation
Fig. 1: the format description figure that controls bag.
Fig. 2: the long schematic diagram that is linear dependence of synchronization delayed time and bag is described.
Fig. 3: the time synchronization error distribution schematic diagram that adopts setting examination and rectification method.
Fig. 4: the sequential schematic diagram that adopts the time synchronization error of setting examination and rectification method.
Fig. 5: the time synchronization error distribution schematic diagram that adopts tracking correction method.
Fig. 6: the sequential schematic diagram that adopts the time synchronization error of tracking correction method.
Fig. 7: two nodes carry out the process schematic diagram of time synchronized.
Fig. 8: the basic principle schematic of minizone correction for mean method.
Fig. 9: the time synchronization error distribution schematic diagram that adopts minizone correction for mean method.
Figure 10: the time synchronization error sequential schematic diagram that adopts minizone correction for mean method.
Embodiment
For making the object, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, embodiments of the present invention are described in further detail.
Core concept of the present invention is: timestamp is beaten and periodically controlled bag bag tail, by the time synchronized time delay of dynamic estimation father and son node, and utilize the synchronization delayed time of estimating to proofread and correct node time, thereby it is internodal synchronous to realize father and son, reaches the object that improves wireless sensor network joint timing tracking accuracy.
Paper implementation method of the present invention below, optional one comprises 8MHz MSP430 microprocessor, 10KB RAM register, 48KB dodges gravel register, the Sensor Network hardware node of 250kbps radio-frequency (RF) transceiver, node time is produced by external clock reference (crystal oscillator), unique definite by three (register) variable TAR, TACCR1 and count.
1, TAR is the hardware register of 16, according to external clock reference counting, can access (the 1tick=2 with tick
-15second) be the time of unit, accuracy of timekeeping reaches Microsecond grade.
2, TACCR1 catches register, can produce TIMER and interrupt when TAR=TACCR1, by the incremental steps of TACCR1 being set as to fixed value INTERVAL, can interrupt counting to TIMER, realizes wider timing.
3, count is the software counter of 32, records TIMER interruption times, thereby obtains Millisecond timing.
Fig. 1 is the time synchronized pack arrangement of low-power consumption method for synchronizing time, and so-called sync packet is at bag tail, to stamp the BEACON bag of timestamp.Whether TYPE is flag bit, show to need synchronous; SenderAddr is sender address, and recipient determines whether its father node accordingly, thereby determines whether need to synchronize with it; TAR and count are timestamp, show the sending node current system time.Because node time is unique definite by TAR, TACCR1 and count, so if can guarantee that these three pairs of parameters of two nodes are consistent, can realize time synchronized.
Suppose that node 1 and 2 nodes will realize time synchronized, node 1 is time reference node (father node), and node 2 is for treating synchronization node (child node).Calibrating principle is as follows:
TAR
2＝TAR
1+ΔT (1)
TACCR1
2＝TAR
2+(INTERVAL-TAR
2％INTERVAL) (2)
TAR
1and count
1can directly from sync packet, extract, INTERVAL is constant, therefore only has a unknown quantity Δ T, and the time delay of sync packet, directly affects synchronization accuracy to the precision of Δ T estimation.
The present invention is placed in the bottom that software can be controlled---the driver of physical layer by the transmitting-receiving of sync packet, utilize to control to wrap and carry timestamp and periodically repeat to send sync packet mechanism, realized the sync packet time delay of introducing and mainly comprised propagation delay time, and it is long directly related with bag.As shown in Figure 2, Fig. 2 shows the long linear dependence that is of synchronization delayed time Δ T and bag, through linear fit, can obtain following empirical equation:
ΔT(tick)＝68.7+1.6*L(byte) (4)
According to above formula, the long L of given bag can obtain Δ T, then according to formula (1-3), can carry out time calibration.On this basis, the present invention proposes 3 kinds of time-correcting methods.
1, setting examination and rectification method
The calibration equation of setting examination and rectification method is as shown in formula (5):
t
2＝t
1+ΔT (4)
Wherein, t
1it is the time of reference node; Δ T is synchronization delayed time correction parameter, and in the method, Δ T tries to achieve according to formula (4); t
2to proofread and correct the time afterwards.
Specific practice of the present invention is: child node is received the control bag that father node sends, and resolves and controls bag, extracts TAR
1information, then estimates Δ T according to bag long L and formula (4), and logical formula (5) calculates the own current time, realizes father and son internodal synchronously.
The time synchronization error distribution schematic diagram that Figure 3 shows that setting examination and rectification method, the probability statistics of its data the results are shown in Table 1, and its synchronous error average is 0.968tick as seen, i.e. 29.54 microseconds, mean square deviation is 1.2054tick, i.e. 36.79 microseconds.Fig. 4 is the sequential schematic diagram of its synchronous error,
The synchronous error probability statistics of three kinds of synchronization correction methods of table 1
2, tracking correction method
As shown in Figure 4, Fig. 4 shows that synchronous error is comparatively stable in short time minizone inter-sync error, and is cyclic variation in long-time large interval inter-sync error.According to this characteristic, we have further proposed tracking correction method and have carried out internodal time synchronized.
The updating formula of tracking correction method is as shown in formula (6):
t
2，n＝t
1，n+(t′
2，n-1-t
1，n-1) (5)
Wherein, subscript n, n-1 represents sampling instant, following table 1,2 represents node number.T
1, n, t
1, n-1represent that respectively reference node is at the time of current time and previous moment, t '
2, n-1the time of synchronization node before previous moment is proofreaied and correct, t
2, nit is the time of synchronization node after proofreading and correct.
Specific practice of the present invention is: child node is recorded the uncorrected time t ' of previous moment
2, n-1and the time t that receives reference node
1, n-1, then according to child node, according to current, receive that the information analysis of controlling bag goes out reference node current time t
1, n, according to formula (6), calculate and estimate the current time t of child node oneself
2, n, realize the internodal time synchronized of father and son.
Adopt the synchronous error of tracking correction method to distribute as shown in Figure 5, the probability statistics of its data the results are shown in Table 1, and its synchronous error mean value is 0.4114tick, i.e. 12.55 microseconds, and mean square deviation is 0.7003tick, i.e. 21.37 microseconds.The sequential chart that the sequential analysis of error is obtained to synchronous error as shown in Figure 6.
Compare with setting examination and rectification method, the synchronization accuracy of tracking correction method is higher, and performance is better.The average of its synchronous error has reduced 57.5%, and variance has reduced 41.9%.
3, minizone correction for mean method
Fig. 6 can reflect the time domain variation tendency of synchronization delayed time Δ T, and Δ T is comparatively stable in short time minizone, and is cyclic variation in long-time large interval.So the present invention adopts the mean value in this minizone to estimate current Δ T.
The basic principle of minizone correction for mean method can be described with Fig. 7 and Fig. 8.As shown in Figure 7, Fig. 7 has described the synchronizing process between node A and B, and node A is at moment T
n, A, Node B is at moment T
n, B' receive this control bag, then through overcorrect, Node B is adjusted to T by the time of oneself
n, B.Before, the time difference between node A and Node B is as follows:
T
n，B′-T
n，A＝ΔT
ｎ+T
drift (7)
Wherein, Δ T
nto estimate the synchronization delayed time obtaining, T by formula (4)
driftit is the deviation that the frequency shift (FS) of crystal oscillator causes.
Because synchronization delayed time Δ T is comparatively stable in short time minizone, the present invention estimates synchronization delayed time more accurately by the Tracing Historical value.Tracing process is as follows:
ΔT
n-ΔT
n-1＝(T
n，B′-T
n，A)-(T
n-1，B′-T
n-1，A) (8)
The present invention estimates current time delay Δ T by following the trail of the history value of 3 times, and as shown in Figure 8, the interval size of taking in Fig. 8 is 3, with the mean value in this interval, replaces Δ T.By experiment, can verify that correction for mean method in minizone can effectively reduce the synchronization delayed time fluctuation in minizone.
Adopt the synchronization delayed time error of minizone correction for mean method to distribute as shown in Figure 9, the probability statistics of its data the results are shown in Table 1, and its synchronous error is 0.6280tick as seen, i.e. 12.55 microseconds, and mean square deviation is 0.7629tick, i.e. 23.28 microseconds.The sequential chart that the sequential analysis of error is obtained to synchronous error as shown in figure 10.
Compare with setting examination and rectification method, the synchronization accuracy of minizone correction for mean method is higher, and performance is better.The average of its synchronous error has reduced 35.1%, and variance has reduced 36.7%.
In order to illustrate that the present invention is in the improvement aspect energy consumption, the present invention and classical RBS and TPSN algorithm contrast.The synchronous error of RBS and TPSN is respectively 29.13 microseconds and 16.9 microseconds, suitable with synchronization accuracy of the present invention, but the method for synchronizing time that the present invention proposes more has superiority aspect energy consumption.
The energy consumption of WSN node is mainly produced by the data transmit-receive of radio-frequency module, therefore can receive and dispatch the energy consumption that number of times carrys out more different synchronized algorithms by sync packet.Consideration in a broadcast domain during a reference node n receiving node synchronization overhead of each algorithm as shown in table 2.Interocclusal record number of times when wherein K is RBS algorithm, K is larger, and synchronization accuracy is higher.Compare with TPSN with RBS as can be seen from Table 2, method for synchronizing time of the present invention can greatly reduce the transmitting-receiving number of times of sync packet, therefore can reduce energy consumption.
The comparison of table 2 algorithms of different synchronization overhead
Said specific embodiment above; that object of the present invention, technical scheme and useful result are further illustrated; institute is understood that; the foregoing is only specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of making, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (4)
1. a wireless senser method for synchronizing time for low-power consumption, is characterized in that:
(1) periodic synchronous information sends, and utilizes to control to wrap and carries synchronizing information;
(2) when recipient receives after sync packet, according to principle time calibration, according to timestamp information calibration oneself time;
Internodal sync packet time delay Δ T proofreading and correct in (3) three kinds of time-correcting method On-line Estimation wireless sensor networks;
(4) with local synchronization, realize the synchronous synchronization mechanism of the whole network, only need father and son's node to carry out synchronously.
2. power consumption wireless sensor method for synchronizing network time according to claim 1, it is characterized in that: the bag tail of controlling bag is stamped timestamp, can save the energy consumption for time synchronized, sync packet only need be added 9 bytes at the bag tail of MAC layer, comprise: TYPE is flag bit show whether to need synchronous; SenderAddr is sender address, and recipient determines whether its father node accordingly, thereby determines whether need to synchronize with it; TAR and count are timestamp, show the sending node current system time.
3. power consumption wireless sensor method for synchronizing network time according to claim 1, it is characterized in that: when recipient receives after sync packet, can calibrate oneself time according to timestamp information, node time is unique definite by TAR, TACCR1 and count, consistent by guaranteeing these three pairs of parameters of two nodes, can realize time synchronized, its calibrating principle is as follows:
Suppose that node 1 and 2 nodes will realize time synchronized, node 1 is time reference node (father node), and node 2 is for treating synchronization node (child node), and calibrating principle is as follows:
TAR
2＝TAR
1+ΔT 3-1
TACCR1
2＝TAR
2+(INTERVAL-TAR
2％INTERVAL) 3-2
TAR
1and count
1can directly from sync packet, extract, INTERVAL is constant, therefore only has a unknown quantity Δ T.
4. power consumption wireless sensor method for synchronizing network time according to claim 1, is characterized in that: propose 3 kinds of methods of estimation internodal sync packet time delay Δ T in wireless sensor network is carried out to On-line Estimation:
(1) setting examination and rectification method
The calibration equation of setting examination and rectification method is as shown in formula (3-4):
t
2＝t
1+ΔT 3-4
Wherein, t
1be the time of reference node, Δ T is synchronization delayed time correction parameter, t
2to proofread and correct the time afterwards;
(2) tracking correction method
The updating formula of tracking correction method is as shown in formula (3-5):
t
2，n＝t
1，ｎ+(t′
2，ｎ-1-t
1，n-1) 3-5
Wherein, subscript n, n-1 represents sampling instant, following table 1,2 represents node number, t
1, n, t
1, n-1represent that respectively reference node is at the time of current time and previous moment, t '
2, n-1the time of synchronization node before previous moment is proofreaied and correct, t
2, nit is the time of synchronization node after proofreading and correct;
(3) minizone correction for mean method
Δ T is comparatively stable in short time minizone, and is cyclic variation in long-time large interval.So can estimate current Δ T with the mean value in this minizone, correction for mean method in minizone can effectively reduce the synchronization delayed time fluctuation in minizone.5, power consumption wireless sensor method for synchronizing network time according to claim 1, it is characterized in that: in data acquisition tree, all exchanges data are all to carry out father node-child node centering, each node only with his father's synchronisation of nodes, by tree topology, with local synchronization, realize the whole network synchronous, the method for synchronization is processed in the following manner:
(1) network can be set up one and take the data acquisition tree that SINK node is root node when initialization;
(2) SINK node periodically sends the BEACON bag that comprises timestamp;
(3) child node parses timestamp after receiving BEACON bag, and according to the clock of formula (3-1～3-3) calibration oneself;
(4) each node also can be broadcasted BEACON bag according to the mode of SINK node after completing synchronous (that is networking), to facilitate adding of new node;
(5) new node adds fashionable can first intercepting a period of time, can choose a father node after collecting the BEACON of neighbor node, and synchronous with it, thereby completes networking;
(6) when topology changes, fall the node of net and can first intercept a period of time, reselect father node, and complete synchronous networking.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310090466.0A CN104053223A (en) | 2013-03-13 | 2013-03-13 | Low-power wireless sensor network time synchronization method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310090466.0A CN104053223A (en) | 2013-03-13 | 2013-03-13 | Low-power wireless sensor network time synchronization method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN104053223A true CN104053223A (en) | 2014-09-17 |
Family
ID=51505484
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310090466.0A Pending CN104053223A (en) | 2013-03-13 | 2013-03-13 | Low-power wireless sensor network time synchronization method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104053223A (en) |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104540212A (en) * | 2014-12-01 | 2015-04-22 | 国网河南省电力公司电力科学研究院 | Wireless sensor network on-demand clock synchronization method based on AODV (Ad Hoc On-Demand Distance Vector) routing protocol |
| CN104581943A (en) * | 2015-01-15 | 2015-04-29 | 浙江大学 | Node locating method for distribution type wireless sensing network |
| CN104602291A (en) * | 2014-12-22 | 2015-05-06 | 浙江大学 | Time measurement method for wireless sensor network |
| CN105307261A (en) * | 2015-11-11 | 2016-02-03 | 中国电子科技集团公司第三十研究所 | Self-synchronization method for oriented Adhoc network |
| CN105491656A (en) * | 2015-10-12 | 2016-04-13 | 山东大学（威海） | Light-weight time synchronization method oriented to large-scale ad hoc network |
| CN105703868A (en) * | 2016-01-19 | 2016-06-22 | 中国科学院信息工程研究所 | Time synchronization method and device for smart device network |
| CN106332264A (en) * | 2015-07-03 | 2017-01-11 | 北京信威通信技术股份有限公司 | Ad-hoc network node synchronization method combining cluster management mechanism |
| CN106455042A (en) * | 2016-12-15 | 2017-02-22 | 无锡源清慧虹信息科技有限公司 | Inter-node time synchronization method, wireless sensor network and node thereof |
| CN107786293A (en) * | 2016-08-29 | 2018-03-09 | 中兴通讯股份有限公司 | Method for synchronizing time, clock equipment, from clockwork and clock synchronization system |
| CN107911207A (en) * | 2017-11-09 | 2018-04-13 | 福州开发区慧聚通信技术有限公司 | A kind of periodic signal synchronous method based on time adjustment |
| CN107995681A (en) * | 2017-11-16 | 2018-05-04 | 全球能源互联网研究院有限公司 | A kind of wireless sense network method for synchronizing time and device |
| CN109074723A (en) * | 2016-04-14 | 2018-12-21 | 日本电信电话株式会社 | Method for synchronizing time, sensor insertion terminal and sensor network system |
| CN109413734A (en) * | 2018-12-14 | 2019-03-01 | 郑州联睿电子科技有限公司 | Base base station and its construction method when a kind of more |
| CN110366101A (en) * | 2019-07-26 | 2019-10-22 | 杭州微萤科技有限公司 | A kind of method that UWB centralization calculating realization positions on a large scale |
| CN110446156A (en) * | 2019-07-26 | 2019-11-12 | 杭州微萤科技有限公司 | A kind of method that the realization of UWB distributed computing positions on a large scale |
| CN111787607A (en) * | 2020-06-30 | 2020-10-16 | 大唐终端技术有限公司 | Method for improving synchronization precision of ad hoc network |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102057616A (en) * | 2008-04-25 | 2011-05-11 | 狄德罗-巴黎第七大学 | Computer device for the time-based management of digital documents |
| CN102118849A (en) * | 2011-03-02 | 2011-07-06 | 重庆邮电大学 | Time synchronization method applicable to wireless sensor network |
| CN102355319A (en) * | 2011-08-17 | 2012-02-15 | 中国科学院深圳先进技术研究院 | Time synchronization method and system for wireless sensor network |
-
2013
- 2013-03-13 CN CN201310090466.0A patent/CN104053223A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102057616A (en) * | 2008-04-25 | 2011-05-11 | 狄德罗-巴黎第七大学 | Computer device for the time-based management of digital documents |
| CN102118849A (en) * | 2011-03-02 | 2011-07-06 | 重庆邮电大学 | Time synchronization method applicable to wireless sensor network |
| CN102355319A (en) * | 2011-08-17 | 2012-02-15 | 中国科学院深圳先进技术研究院 | Time synchronization method and system for wireless sensor network |
Cited By (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104540212A (en) * | 2014-12-01 | 2015-04-22 | 国网河南省电力公司电力科学研究院 | Wireless sensor network on-demand clock synchronization method based on AODV (Ad Hoc On-Demand Distance Vector) routing protocol |
| CN104540212B (en) * | 2014-12-01 | 2019-01-25 | 国网河南省电力公司电力科学研究院 | The on-demand clock synchronizing method of wireless sensor network based on AODV Routing Protocol |
| CN104602291A (en) * | 2014-12-22 | 2015-05-06 | 浙江大学 | Time measurement method for wireless sensor network |
| CN104602291B (en) * | 2014-12-22 | 2018-06-15 | 浙江大学 | A kind of method of time measurement in wireless sensor network |
| CN104581943A (en) * | 2015-01-15 | 2015-04-29 | 浙江大学 | Node locating method for distribution type wireless sensing network |
| CN104581943B (en) * | 2015-01-15 | 2018-02-13 | 浙江大学 | Node positioning method for Distributed Wireless Sensor Networks |
| CN106332264A (en) * | 2015-07-03 | 2017-01-11 | 北京信威通信技术股份有限公司 | Ad-hoc network node synchronization method combining cluster management mechanism |
| CN105491656B (en) * | 2015-10-12 | 2019-08-13 | 山东大学（威海） | A kind of lightweight method for synchronizing time towards extensive ad hoc network |
| CN105491656A (en) * | 2015-10-12 | 2016-04-13 | 山东大学（威海） | Light-weight time synchronization method oriented to large-scale ad hoc network |
| CN105307261B (en) * | 2015-11-11 | 2019-02-01 | 中国电子科技集团公司第三十研究所 | A kind of orientation Ad hoc network motor synchronizing method |
| CN105307261A (en) * | 2015-11-11 | 2016-02-03 | 中国电子科技集团公司第三十研究所 | Self-synchronization method for oriented Adhoc network |
| CN105703868A (en) * | 2016-01-19 | 2016-06-22 | 中国科学院信息工程研究所 | Time synchronization method and device for smart device network |
| CN105703868B (en) * | 2016-01-19 | 2018-11-30 | 中国科学院信息工程研究所 | A kind of method for synchronizing time and device for smart machine network |
| US10862602B2 (en) | 2016-04-14 | 2020-12-08 | Nippon Telegraph And Telephone Corporation | Time synchronization method, sensor data acquisition terminal, and sensor network system |
| CN109074723A (en) * | 2016-04-14 | 2018-12-21 | 日本电信电话株式会社 | Method for synchronizing time, sensor insertion terminal and sensor network system |
| CN107786293A (en) * | 2016-08-29 | 2018-03-09 | 中兴通讯股份有限公司 | Method for synchronizing time, clock equipment, from clockwork and clock synchronization system |
| CN106455042B (en) * | 2016-12-15 | 2019-10-11 | 无锡源清慧虹信息科技有限公司 | A kind of time synchronization between nodes method, wireless sensor network and its node |
| CN106455042A (en) * | 2016-12-15 | 2017-02-22 | 无锡源清慧虹信息科技有限公司 | Inter-node time synchronization method, wireless sensor network and node thereof |
| CN107911207A (en) * | 2017-11-09 | 2018-04-13 | 福州开发区慧聚通信技术有限公司 | A kind of periodic signal synchronous method based on time adjustment |
| CN107995681A (en) * | 2017-11-16 | 2018-05-04 | 全球能源互联网研究院有限公司 | A kind of wireless sense network method for synchronizing time and device |
| CN109413734A (en) * | 2018-12-14 | 2019-03-01 | 郑州联睿电子科技有限公司 | Base base station and its construction method when a kind of more |
| CN110366101A (en) * | 2019-07-26 | 2019-10-22 | 杭州微萤科技有限公司 | A kind of method that UWB centralization calculating realization positions on a large scale |
| CN110446156A (en) * | 2019-07-26 | 2019-11-12 | 杭州微萤科技有限公司 | A kind of method that the realization of UWB distributed computing positions on a large scale |
| CN111787607A (en) * | 2020-06-30 | 2020-10-16 | 大唐终端技术有限公司 | Method for improving synchronization precision of ad hoc network |
| CN111787607B (en) * | 2020-06-30 | 2023-04-18 | 大唐终端技术有限公司 | Method for improving synchronization precision of ad hoc network |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104053223A (en) | Low-power wireless sensor network time synchronization method | |
| Hasan et al. | Time synchronization in vehicular ad-hoc networks: A survey on theory and practice | |
| Akhlaq et al. | RTSP: An accurate and energy-efficient protocol for clock synchronization in WSNs | |
| CN102118849B (en) | Time synchronization method applicable to wireless sensor network | |
| CN101335587B (en) | Accurate time synchronization method for industrial wireless network | |
| US20140355628A1 (en) | Recursive time synchronization protocol method for wireless sensor networks | |
| Gong et al. | CESP: A low-power high-accuracy time synchronization protocol | |
| Djenouri et al. | Fast distributed multi-hop relative time synchronization protocol and estimators for wireless sensor networks | |
| Huang et al. | Long term and large scale time synchronization in wireless sensor networks | |
| CN101588628A (en) | Clock synchronizing method for wireless sensor network | |
| CN105188126B (en) | Distributed multihop wireless network clock synchronizing method based on mean field | |
| CN102752843B (en) | A kind of method for synchronizing time | |
| CN102196554A (en) | Method for realizing average clock synchronization of wireless sensor network through cluster averaging | |
| CN100588147C (en) | Low-overhead high-precision time synchronization method of wireless mesh network for industrial monitoring | |
| Chen et al. | An implementation of IEEE 1588 protocol for IEEE 802.11 WLAN | |
| CN101982959B (en) | Network demand time synchronization method | |
| Wang et al. | Estimation of frequency offset for time synchronization with immediate clock adjustment in multihop wireless sensor networks | |
| CN103002562A (en) | Hardware synchronizing method and system of wireless sensing network | |
| CN103957591A (en) | Node pair based wireless sensor network time synchronization method | |
| Liang et al. | An extremely accurate time synchronization mechanism in fog-based vehicular ad-hoc network | |
| Albu et al. | An energy-efficient clock synchronization protocol for Wireless Sensor Networks | |
| Gautam et al. | A comparative study of time synchronization protocols in wireless sensor networks | |
| CN107959968B (en) | High-precision low-overhead wireless sensor network clock synchronization method | |
| Bae et al. | Time synchronization in wireless sensor networks | |
| Allard et al. | Fully distributed clock synchronization in wide-range TDMA ad-hoc networks |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20140917 |
|
| WD01 | Invention patent application deemed withdrawn after publication |