CN1893380A - Energy-saving method of wireless self-combining network - Google Patents
Energy-saving method of wireless self-combining network Download PDFInfo
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- CN1893380A CN1893380A CNA2006100252474A CN200610025247A CN1893380A CN 1893380 A CN1893380 A CN 1893380A CN A2006100252474 A CNA2006100252474 A CN A2006100252474A CN 200610025247 A CN200610025247 A CN 200610025247A CN 1893380 A CN1893380 A CN 1893380A
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Abstract
Reducing proportion of active time in whole cycle of active/sleep, the method lowers energy consumption of each node in self-organized network so as to provide energy saving work mode of self-organized network. The method reduces ratio of active time/sleep time to 1/100 or less. Thus, survival time of wireless self-organized network reaches to more than one month.
Description
Technical field
The present invention relates to wireless communication field, particularly the wireless self-networking system.It specifically is a kind of simple and effective power-economizing method of wireless self-networking.
Background technology
Node in the wireless self-networking adopts battery that energy is provided usually, operable electric weight is very limited, for applying to some particular surroundings or the wireless sensor network of thousands of nodes being arranged, replacing to battery is impossible, but the life span of wireless sensor network but requires to reach several months even several years, must improve the capacity usage ratio of each node, to prolong the life-span of network as far as possible.
The power saving of wireless self-networking relates to each layer of wireless Ad Hoc (Ad Hoc) network protocol stack.Up to the present, people have proposed the solution of many software and hardwares.For example: modulating mode selection, link-layer optimization, traffic distribution, Topology Management, calculating and the scheme such as compromise of communicating by letter.But these schemes all are the conservation measuress under transmission state and accepting state, and the time that general node is in transmission and accepting state only accounts for the minimum part of whole active state, and the most of the time is in idle condition.In wireless self-networking, most of energy is consumed by the idle condition of node, and the energy that is used for practical communication only accounts for whole catabiotic parts.Can therefore, idea be exactly the most intuitively: reduce the time of node active state as far as possible, and not influence the connectedness of network.This method just from this point of view.
IEEE 802.11 (wireless LAN medium MAC layer and physical layer protocol) working group proposed the energy saver mode of a kind of use distributed coordination function (DCF).This energy saver mode requires all nodes synchronous, enters active state when each signal slot begins simultaneously, and keeps active state a period of time, i.e. ATIM (Ad hoc communicate by letter Indication message) window.All nodes all are in active state in the ATIM window, and therefore the node that has data to send must take advantage of this window to send or the notice receiving node.In case receive the ATIM frame, receiving node judges at first whether this ATIM bag requires broadcast or multicast, if not ATIM-ACK bag of loopback immediately then.So far, finished the ATIM handshake procedure after, send out to receive both sides' node and begin to transmit and receive data in the mode of RTS (request time sheet)-CTS (free time sheet)-DATA (data)-ACK (affirmation).The node that does not have data to send and receive then enters resting state, begins up to the next signal time slot.
Under the energy saver mode of distributed coordination function (DCF), the ATIM window of signal slot just is used for connecting and does not send data, the ATIM window has great influence to network throughput and energy consumption: if the ATIM window is too little, can cause not having time enough to send the ATIM frame, send thereby influence data; If the ATIM window is too big, then there is not time enough to send Frame, can limiting network throughput throughput.The ATIM window can not be obtained too little, and it makes 802.11 agreements can not obtain good energy-saving effect.
Summary of the invention
The object of the present invention is to provide a kind of power-economizing method of wireless self-networking, reduce the energy consumption of each node, prolong the useful life of network.
In order to achieve the above object, the present invention adopts following technical proposals:
A kind of power-economizing method of wireless self-networking is characterized in that reducing the energy consumption of each node of wireless self-networking by reducing the time of enlivening shared ratio in whole enlivening/dormancy period, prolongs the useful life of network.
For reducing the time of enlivening shared ratio in whole enlivening/dormancy period, adopt following energy-conservation wireless self-networking mode of operation:
(1) all node retention times are synchronous, when beginning, each signal slot enters active state, open radio-frequency (RF) transceiver and processor in the time interior nodes of enlivening, can send the beacon frame (Beacon) and the data that comprise temporal information, several signal slots of beacon frame interval just send once.Enter dormancy time after enlivening the time, enter the time of enlivening again after the dormancy, circulation is so always gone down.A complete active/dormancy period is called a signal slot.
(2) at first monitor beacon frame after each node powers on, following two kinds of situations arranged:
1. first kind of situation is that this node has been received the beacon frame that other node sends, and it is made as non-coordinator with this node, and non-coordinator can only transmit the beacon frame that other node sends, and oneself can not initiatively send beacon frame.In case this node becomes non-coordinator, it receives only beacon frame after each signal slot begins, and when still can not receive beacon frame through 3 to 5 signal slots, this node is made as the coordinator with this node behind random delay, and the coordinator can initiatively send beacon frame.
2. second kind of situation is to can not receive beacon frame after this node is opened in 3 to 5 signal slots, and it is made as the coordinator with this node, can initiatively send beacon frame later on.
(3) when arrive should dormancy time, but also have data not distribute or when also having data not harvest, node does not enter resting state, wait transmitting-receiving and reply and finish the back as if enough reentrant resting states of residue dormancy time node are arranged.After node entered resting state, radio-frequency (RF) transceiver will be introduced into resting state, and processor also enters resting state when processor does not have data processing task afterwards.
(4) because data sudden in the sensor network do not have data to be sent out in the most of the time.Also do not receive the data that other node is sent if node has data to send in the time of enlivening, then it can enter resting state at once after the time of enlivening finishes.
The ratio that enlivens time and dormancy time reaches 1/100 or littler, and the life span of whole wireless self-networking just can reach more than one month.
The present invention compared with prior art, it has following conspicuous outstanding substantive distinguishing features and remarkable advantage:
This method has following advantage:
(1) it is few to take resource.This method algorithm is easy, takies processor extra computation resource hardly, therefore can be embedded in other program.Compare the Frame much shorter because of beacon frame again, and just send once in a while, so beacon frame only takies the network bandwidth seldom.
(2) program modularity is realized easy.Only need in original program, to add and just can reach energy-saving effect at once with energy-conservation relevant code.
(3) energy-saving effect is remarkable.When employing enlivens 100 milliseconds of times, during 1 second mode of dormancy time, can save the energy more than 90%; When dormancy time was longer, energy-saving effect was better obviously.For sensor network, the life span of network is vital, and this method can make battery powered wireless sensor network use the longer time and not need to change battery.
(4) adaptivity.This method can be regulated automatically according to the load of network and be enlivened time span.When offered load is low, can shortens automatically and enliven time span, to save more energy; And when offered load is high, can increases automatically and enliven time span, to reduce time-delay.
Description of drawings
Fig. 1 is the regional repeating process schematic diagram of wireless self-networking Beacon.
Fig. 2 is the forwarding mechanism schematic diagram of dormancy.
Fig. 3 is that Beacon sends schematic diagram at interval.
Fig. 4 is the flow chart of changing the mechanism of transmitting-receiving Beacon.
Fig. 5 is the dormancy mechanism flow chart of radio-frequency (RF) transceiver and processor.
Fig. 6 is the frame assumption diagram of beacon frame.
Embodiment
Details are as follows in conjunction with the accompanying drawings for a preferred embodiment of the present invention:
The components and parts that each node test of native system is used all are the general-purpose devices on the market.What microprocessor adopted can be 8 single-chip microcomputers of Atmel company or Texas Instruments.Radio-frequency (RF) transceiver is used the CC2420 chip of Chipcom company.The small-scale lithium ion cell capacity is approximately 2200mAh, if can reach the average system current drain of 2mA, then battery approximately can be with one month.
Energy-conservation and minimizing time delay is a pair of paradox: for energy-conservation node must reduce the time that is in active state as far as possible, because the foundation of wireless self-networking need spend the plenty of time, thereby cause the increase of total time delay; In order to reduce time delay, node must keep active state constantly, from and increased energy consumption.Except the data that send self perception, each node all is again a router, need E-Packet for other node.Under typical wireless sensor network environment, most of message (probably having 65%) that wireless sensor node receives need be transmitted to other node.The power-saving mechanism that this method proposes will be realized a kind of balance just between the two: the average current consumption of node is 2mA, query sensors, processing and transmission sensing data after node is waken up and come, and then reenter park mode.Enliven the time and dormancy time length is decided by the size of concrete application scenario and each data volume.For common sensor application occasion, each wireless sensor node need will send every just having a packet more than 10 seconds usually, therefore can be taken as 100 milliseconds the time of enlivening, and dormancy time is taken as 900 milliseconds.
The performing step of this section energy method is described with Fig. 1 below.As shown in Figure 1, No. 2 nodes supposing the a-quadrant are opened at first.
(1) it at first monitors beacon frame, if do not receive beacon frame, then thinking does not have other node around own, this node is made as the coordinator, and sets up initial routing table in 12 seconds, and No. 2 nodes of each signal slot will initiatively send beacon frame later on.The local zone time that in beacon frame, has comprised No. 2 nodes.No. 2 nodes are in each signal slot (length is 1 second), and preceding 100 milliseconds are the time of enlivening, and open radio-frequency (RF) transceiver, send data or transmit data; The back is a dormancy time for 900 milliseconds, closes radio-frequency (RF) transceiver and processor.
(2) afterwards, the B zone No. 4 nodes are opened.After receiving the beacon frame that No. 2 nodes send, No. 4 nodes are immediately according to time of the time information renovation oneself that comprises in the beacon frame of receiving, synchronous with No. 2 nodes, and this node is made as non-coordinator, No. 4 nodes of each signal slot receive only beacon frame later on.With similar method, No. 1 node and No. 3 nodes add this network.
(3) because beacon frame is a broadcast packet, each node forwards after the life cycle in the beacon frame of receiving, (TTL) subtracted 1, is kept at 0 o'clock until TTL and abandons this beacon frame.
(4) the C zone No. 5 nodes are after receiving the beacon frame that No. 4 nodes are transmitted, and are synchronous with No. 4 nodes, and this node is made as non-coordinator, and No. 5 nodes of each signal slot also receive only beacon frame later on, and transmit beacon frame.Other node in the C zone adds this network by No. 5 nodes.
(5) node in the whole network adopts identical active/dormancy time ratio, and 100 milliseconds is the time of enlivening, and back 900 milliseconds is dormancy time.All node times are synchronous, when beginning, each signal slot successively enters active state and resting state (see figure 2) according to the beacon frame transmissions path direction, the radio-frequency (RF) transceiver of node and processor all are in resting state in the whole network of dormancy time, and this can prolong the life span of network.
(6) when the non-coordinator's node in the network can not receive beacon frame above 20 seconds, through behind the random delay this node is made as the coordinator, each signal slot only sends beacon frame later on.
(7) arrive when dormancy time, but also have data not distribute or when also having data not harvest, node does not enter resting state, wait transmitting-receiving and reply and finish the back as if enough reentrant resting states of residue dormancy time node are arranged.After node entered resting state, radio-frequency (RF) transceiver will be introduced into resting state, and processor also enters resting state when processor does not have data processing task afterwards.
(8) will send data to next-hop node when this node, and next-hop node is when being in resting state, this packet of this nodal cache, the next signal time slot resends again by the time, if still not success after having three tries then abandons this packet.
As shown in Figure 2, after network was set up, all node times were synchronous, successively enter active state according to the beacon frame transmissions path direction and can realize the shortest downlink information transmission delay when each signal slot begins.Arrive C because the down link direction is A to B, the B node is waken up than the late bag transmitting time of A node (5 to 10 milliseconds), and the C node is waken up than the late bag transmitting time of B node again.
Node can send beacon frame (BC), the route of carrying time synchronization information and set up request and sensing data (DA) etc. in the time of enlivening.In a certain node is installed in a certain zone and after opening, when entering in the signal cover of former network, this node will be received beacon frame, comprise the information of this network of network number, network capacity and time slot allocation strategy during this information of same.This node can be according to beacon frame and this Network Synchronization, and sends service request in the time of enlivening.The node adjacent with this node can send acknowledgement frame, agrees that this node adds network, and can send the routing table update order.Afterwards, this node just can directly communicate with these nodes.Wherein t2-t1 is the active state time of A node signal time slot, and t3-t2 is the resting state time of A node signal time slot, the more little just power saving more of the ratio of their time, but also will take into account the size of each transmission data volume and require the collection period of data.
The beacon frame that the employed beacon frame of this method is adopted based on IEEE 802.15.4 (low rate wireless personal network medium access key-course and physical layer protocol) is revised and is got.
802.15.4 one that is the proposition of ieee standard association at low rate wireless personal domain network (Low-RateWireless Personal Area Network, standard LR-WPAN).This standard is low-energy-consumption, lower rate transmissions, low-cost as highest priority, be intended to in individual or the home-ranges between the distinct device low rate interconnection unified standard is provided.In 802.15.4, adopt beacon frame delivery network information, synchronizing information, dormancy strategy and medium access right etc.Active and the dormancy of whole network are all controlled by beacon frame.
The concrete frame structure of the beacon frame that adopts in this method is as shown in Figure 6:
In the frame control domain, dormancy strategy (Sleep Scheme) information and jumping figure (Hop Count) information have been added.Dormancy strategy is informed the concrete dormancy strategy of other this node of node, and 1 expression is active, 0 expression dormancy.Jumping figure is informed the jumping figure of other this node of node apart from telegon, and minimum is 0, and maximum is 3.
| Position: 0-2 | 3 | 4 | 5 | 6 | 7-9 | 10-11 | 12-13 | 14-15 |
| Frame type | Whether encrypt | Data are ended sign | Request is confirmed | Sign in the net | Dormancy strategy | The destination address pattern | Jumping figure | The source address pattern |
Frame control domain (Frame Control Field) structure
The dormancy strategy flag bit is optionally, when adopting burst, is about to the time of enlivening when being divided into 8 isometric timeslices, and 3 dormancy strategy signs can indicate this node to be in active state in those timeslices.After node has been received the beacon frame that other node sends, the dormancy strategy that dormancy strategy information that this node can be comprised according to the frame control domain in the beacon frame of receiving and jumping figure information decide oneself.When calculating by special algorithm, node only needs to open radio-frequency (RF) transceiver in certain several timeslice, then it can write the dormancy strategy of oneself in the beacon frame that oneself sends, and according to this dormancy strategy in that the time of enlivening is also closed radio-frequency (RF) transceiver accordingly, this can reduce energy consumption, also can reduce simultaneously unnecessary data and send, thus the chance of minimizing data collision.
As shown in Figure 3, each node experience enters dormancy time after enlivening time, when dormancy time to and enter active state, circulation is so always gone down.Because the clock jitter of single-chip microcomputer is significantly smaller than signal slot, so that improve the efficient and the power saving of synchronizing information, just beacon frame can send once by several signal slots of interval.T5-t4 is for sending the time interval (BI) of beacon frame among the figure, and the choosing of BI should be considered that power saving has and not have too big deviation the lock in time that will consider each node.
Be illustrated in figure 4 as the program realization block diagram that the transmitting-receiving beacon frame is changed the mechanism.The synchronization mechanism of network has self-reparing capability, when the coordinator's node failure in the network, when removing or damaging, non-coordinator node is overtime when can not receive beacon frame, avoid sending beacon frame simultaneously and clash in order to make each non-coordinator's node, when non-coordinator node is not received beacon frame behind random delay, just this node is made as the coordinator, sends beacon frame.Non-like this coordinator node just can be taken on coordinator node by one of them by automatic synchronization, has rebulid the synchronization mechanism that sends beacon frame.
The program that is illustrated in figure 5 as the dormancy mechanism of radio-frequency (RF) transceiver and processor realizes block diagram.Radio-frequency (RF) transceiver and processor are not to enter resting state simultaneously, and radio-frequency (RF) transceiver enters dormancy prior to processor, revive in processor in the back.Because processor is except carrying out wireless receiving and dispatching, also to carry out processing such as serial communication, data acquisition, data processing, route maintenance and information intransit buffering formation maintenance.When dormancy time arrives, but also have data not distribute or when also having data not harvest, node can not enter resting state, transmitting-receiving such as have only and reply finish and when also having enough remaining times node just can enter resting state.When node will enter resting state, at first radio-frequency (RF) transceiver can enter resting state (low power consumpting state), finished all Processing tasks preprocessors when processor then and also can enter resting state.Before the node dormancy time finished, processor can at first be waken up, and radio-frequency (RF) transceiver also can be waken up afterwards, and at this moment node has just entered active state.
Claims (3)
1. the power-economizing method of a wireless self-networking is characterized in that reducing the time of enlivening shared ratio in whole enlivening/dormancy period, reduces the energy consumption of each node of MANET, prolongs the useful life of network.
2. the power-economizing method of wireless self-networking according to claim 1, it is characterized in that for reduce the time of enlivening whole active/dormancy period in shared ratio, adopt following energy-conservation wireless self-networking mode of operation:
(1) all node retention times are synchronous, when beginning, each signal slot enters active state, open radio-frequency (RF) transceiver and processor in the time interior nodes of enlivening, can send the beacon frame and the data that comprise temporal information, but beacon frame just sends once at the some signal slots in interval; Enter dormancy time after enlivening the time, a complete active/dormancy period constitutes a signal slot;
(2) at first monitor beacon frame after each node powers on, following two kinds of situations arranged:
1. this node has been received the beacon frame that other node sends, and then this node is made as non-coordinator, can only transmit the beacon frame that other node sends, and oneself can not initiatively send beacon frame, receives only signal frame after each signal slot begins; When can not receive beacon frame through 3 to 5 signal slots, behind random delay, this node is made as the coordinator, can initiatively send beacon frame;
2. this node is opened in 3 to 5 signal slots in back and be can not receive beacon frame, then this node is made as the coordinator, can initiatively send beacon frame subsequently;
(3) when arrive should dormancy time, but also have data not distribute when data do not harvest in addition, node does not enter resting state, waiting transmitting-receiving and replying has enough residue dormancy times after finishing, this node enters dormant state again; After this node entered resting state, radio-frequency (RF) transceiver will enter resting state, also entered resting state afterwards when processor does not have data processing task;
(4) if node does not have data to send, also do not receive the data that other node is sent in the time of enlivening, then it can enter resting state at once after the time of enlivening finishes.
3. the power-economizing method of wireless self-networking according to claim 2 is characterized in that the ratio of the time of enlivening and dormancy time is decreased to 1/100 or littler, and it can reach more than one month the life span of wireless self-networking.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101753241A (en) * | 2008-12-10 | 2010-06-23 | 财团法人资讯工业策进会 | Network synchronization method and system |
| CN101567820B (en) * | 2008-04-24 | 2011-01-26 | 魏昕 | Energy-saving medium access control method in underwater acoustic network |
| CN101325604B (en) * | 2008-07-21 | 2011-06-08 | 重庆邮电大学 | Energy-saving method for distributed self-adaption industry wireless network |
| CN101299699B (en) * | 2007-04-30 | 2011-06-15 | 韩国电子通信研究院 | Node device and method for beacon scheduling in AD-HOC network and data transmitting method thereof |
| CN106358273A (en) * | 2016-08-11 | 2017-01-25 | 矽力杰半导体技术(杭州)有限公司 | Low-power-consumption communication device |
| CN107172660A (en) * | 2017-03-15 | 2017-09-15 | 北京交通大学 | A kind of Beacon coordination systems suitable for sensor network protocol |
| WO2022126398A1 (en) * | 2020-12-15 | 2022-06-23 | 华为技术有限公司 | Message notification method and apparatus |
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2006
- 2006-03-30 CN CNB2006100252474A patent/CN100486195C/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101299699B (en) * | 2007-04-30 | 2011-06-15 | 韩国电子通信研究院 | Node device and method for beacon scheduling in AD-HOC network and data transmitting method thereof |
| CN101567820B (en) * | 2008-04-24 | 2011-01-26 | 魏昕 | Energy-saving medium access control method in underwater acoustic network |
| CN101325604B (en) * | 2008-07-21 | 2011-06-08 | 重庆邮电大学 | Energy-saving method for distributed self-adaption industry wireless network |
| CN101753241A (en) * | 2008-12-10 | 2010-06-23 | 财团法人资讯工业策进会 | Network synchronization method and system |
| CN101753241B (en) * | 2008-12-10 | 2013-07-17 | 财团法人资讯工业策进会 | Network synchronization method and system |
| CN106358273A (en) * | 2016-08-11 | 2017-01-25 | 矽力杰半导体技术(杭州)有限公司 | Low-power-consumption communication device |
| CN107172660A (en) * | 2017-03-15 | 2017-09-15 | 北京交通大学 | A kind of Beacon coordination systems suitable for sensor network protocol |
| CN107172660B (en) * | 2017-03-15 | 2020-01-21 | 北京交通大学 | Beacon coordination mechanism suitable for sensor network protocol |
| WO2022126398A1 (en) * | 2020-12-15 | 2022-06-23 | 华为技术有限公司 | Message notification method and apparatus |
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