19
Distributed TDMA-Base Scheduling in
Multi-hop Wireless Sensor Network
Hojjat Farshadinia, Mohammad reza Noreimehr, and Ehsan Gholami
Department of computer Management, College of computer, Ahvaz Branch, Islamic Azad
University, ahvaz, Iran
Department of computer Management, College of computer, Ahvaz Branch, Islamic Azad
University, ahvaz, Iran
Department of computer Management, College of computer, shoushtsar Branch, Islamic Azad
University, shoushtsar, Iran
Abstract
Inmost wireless sensor networks applications, charging the nodes batteries is impossible, so the protocols designed for these networks should save the energy as much as possible and decrease the overhead caused by sending data, thus energy consumption and wave interferences between the nodes. Shortage of resources and disturbance in network functionality, are another topics discussed in wireless sensor networks. In wireless sensor networks, the information nature and the quality of their exchange in the network have a special property which will lead to using special techniques and methods that are only ideally efficient in such networks. In this thesis, using several protocols in medium accession layer control and combining them for appropriate timing and better management of network structure, a method is proposed to best utilize sources and reducing network disturbances than the previous proposed methods.
Keywords:medium accession control layer, energy consumption, network functionality, protocol.
I. Introduction
20
Among the existing and important topics in sensor networks, is routing and exchanging information methods between the networks nodes which is highly dependent on the limitations, existing sources in the facilities provided from the other network layers. Choosing routing appropriate algorithm with desired working nature and situation has a significant effect on network efficiency evaluation parameters and also its costs, since the defined and structured principles of the desired network must be considered. In wireless sensor networks nature and exchanging information methods in network have a special property which will lead to using special techniques and methods that are only ideally efficient in such networks. Hierarchical routing protocols are a specific type of sensor networks routing protocols. In these protocols,the nodes re divided into logical clusters. In every cluster one node is taken as head cluster and the other nodes are taken as the cluster members. The cluster members get the desired information from the environment, and then send it to the head cluster. The head cluster will send this information to the central node after obtaining them. Choosing appropriate topology for a sensor network has a considerable effect on that network efficiency specially its energy consumption and lifetime. Several topology control protocols have been proposed to allow the nodes to adjust their transport domain or select their desired neighbors. This transport domain must be such that the constructed structure will be able to support energy aware routing and generally increase network efficiency (Goldsmith and Wicker, 2002).
Resource shortage and disturbance in network functionality is the most important topic discussed here, and Ii this method, using several protocols in medium accession layer control and combining them in network structure, we have best utilized the method and have significantly reduced the network disturbances and have reached it to the productivity level.
II. Related works
Panda and Ranjan Patra (2010), Provided a WSN insight according to CSMA based AMC and evaluated the model using different performances measurements. Using MATLAB, they simulated the SINR radio model and radio model using rail disappearance for the covering tree and routing according to geographical angle based on simulated WSN model. Simulation results showed that the simulator under evaluation can recognize WSN behavior in packets number sent or received approximate situation.
Teng and Kim (2010), introduced the real world special requirements of MAC protocol in wireless sensor networks. They then classified a set of recently discussed real world Mac protocol in wireless sensor and described their advantages and disadvantages in every possible time.
Chowdhury and Tauhidul Islam (2010), showed the advantages and disadvantages of using RTS/CTS packets and compared it to CSMA (not using RTS/CTS) and IEEE 802.11(using RTS/CTS). Using a special scenario showed that IEEE 802.11 has a better performance than CSMA. In this research work, the observations indicate that many on the works have been conducted for considering the appropriate IEEE 802.11 in Mac protocol layer for WSNs.
Saha et al. (2011), proposed a scheduling solid method to solve diverse timing problem of the boundary nodes in S-MAC and examined its performance via the simulator. Simulation results showed that boundary nodes consume less energy in large and small networks.
21
quality. It is a method which dynamically provides the collection of ways and mediate accession in order to minimize energy consumption n increase sensor life time. They summerized dynamic source routing and TDMA based on medium accession control. They proposed APCRP- MAC protocol which reliably improves and increases sensor networks lifetime and decreases power consumption.
Jandaeng et al. (2011), proposed packet scheduling protocol (PSA) in order to decrease packet density in Mac layer. This algorithm results in an overall decrease in packet contacting the system. Compared with CSMA/MA, PSA is simpler than the other topology scales used in mathematical method. PSA throughput is better than other algorithms and has lower delay than the previous algorithms. It also uses a better channel of algorithms.
Atefi et al. (2011), discussed on some attributes and limitations of the operative design in wireless sensor networks and the effort performed by researches on message scheduling and scheduling strategy for the operative design in wireless sensor networks and why they used the axle event mechanism in scheduling FIFO in TinyOS operative system. They proposed a real time programming strategy (RTS) which uses an exclusive way to get ensured of this hard real time programming. According to the obtained results they proved that RTS throughput and overloading have a good performance in communications.
Chen et al. (2012), proposed an algorithms to increase programming lifetime and low depression data accumulation (L4DAS) in wireless sensor networks. They officially compiled and formulated the problem of increasing lifetime and minimizing accumulation programming as a limited optimizing problem. Then they proposed an approximate algorithm suggested for this problem by making minimum limited degree height of the covering tree as the accumulation tree and designing a maximum priority programming scheme interference with node transfer program. They finally proved the algorithm via simulation and comparison.
Taruna et al. (2012), proposed a routing protocol based on multi hub cluster which is more efficient than single hub cluster. Simulation results showed that the protocol has a better network lifetime and energy consumption by improving FND (first node death) than single hub cluster routing protocol.
Patil et al. (2013), introduced MAC protocols used for wireless sensor networks (WSNs). They offered protocol correction to improve WSN energy use, delaying time, and throughput. They examined some examples of the protocols energy savings in MAC layer and network layer and compared their performances. Comparing advantages and disadvantages of these protocols, they performed some new researches towards the energy strategy in provided a reference for being used more in wireless receiver network.
Rahmani et al. (2013), proposed n acceptable free contact algorithm in which it is tried to reduce time gaps and increase network power consumption s much s possible.
Rao and Dakshayini (2014), studied QOS aware MAC protocol in multimedia wireless sensors networks and reveled the main current challenges in designing such protocols.
Harkut et al. (2014), provide an overall view of the current scheduling which helps in doing the programmed duties in the system real time. They discussed their works on sensor network operative system. As a result they used OS-IIμC/OSII micro control with EDF algorithm.
22
III. Methods
A. Proposed method
In this section the distributed scheduling protocol based on time division multi access in multi step wireless sensor networks is described. The proposed protocols are based on nodes organization according to combination of different protocols which will be used efficiently and effectively in different parts of the proposed protocol so that it is tried in different parts of the proposed protocol to use the previous proposed protocols such that utilize their advantages more effectively. The proposed protocol uses both CSMA and TDMA in scheduling the accession to the nods common channel in wireless sensor networks. The proposed protocol performs sensor nodes scheduling work by default according to CSMA (in light traffic). By increasing network traffic, the proposed protocol performs scheduling network nodes according to CSMA and TDMA synthetically and simultaneously. In other words, it sends and receives short and long packets by CSMA and TDMA respectively.
B. proposed protocol structure
The proposed protocol is composed of 3 parts as follows each performing its own duties:
● Network nodes clustering ● Cluster nodes scheduling ● Cluster head clusters scheduling
The proposed protocol block diagram is shown in Figure 1.
Figure. 1. the proposed protocol block diagram
In the proposed protocol, first the network is clustered into the parts, and then each cluster schedules the nodes which have data to receive or send separately. Each cluster in the network has a head cluster which is performed in the third part of the proposed protocol's sending data from the head cluster to the network central station or the next step of multi step networks. In Figure 2, the structure of a network is shown after executing the proposed protocol on it theorically.
Start
Network nodes clustering
Cluster nodes scheduling
Cluster head clusters scheduling
23
Figure. 2. the network theorical structure after executing the proposed protocol
C. Network nodes clustering and routing
Network nodes' clustering is done by the chief director and according to traffic and network status (high or low traffic). In each node there is one or more head cluster. Head clusters cluster the nodes according to HEED protocol, and based on this protocol he node select and replace its head cluster when necessary. Of course, any other method or protocol could be used in this section for clustering the nodes and selecting its own head cluster which we use HEED proposed as the execution method.
D. Cluster nodes scheduling
In this section, according to FlexiTP protocol, the corresponding routing tree is obtained. FlexiTP protocol includes two phases performed in each cluster. These two phases are the primary network operation and collecting the information. Collecting information is done through the tables which are divided between each branch nodes. In FlexiTP protocol, the collecting information phase is performed primarily and only in network operation. In the proposed protocol the buffers are used to repeat this phase several times. In following the buffers components will be described. On one hand, in this section we can use any other protocols for scheduling cluster nodes. On the other hand, the proposed protocol has a director and several head cluster, each of the clusters having one or more head cluster which are divided according to the their distance between several nodes. The chief director directs the head clusters.
E. scheduling head clusters of the wireless networks by the network chief director
24
of very low power consumption in light traffics and high energy exploring in heavy traffics using preliminary sampling combination with the preliminary waking up length quantification. In the proposed protocol the network chief director makes the head clusters nodes and data exchange with the central station (chief director) according to a Wise-MAC protocol and via head cluster in each cluster and exchanging control messages. In the followings the control packets structure of the head cluster nodes buffers and chief director in the proposed protocol will be described.
IV. Simulating the proposed protocol
In this section, the proposed protocols accuracy will be assured by simulating the proposed protocols and conducting several tests on these simulations. All simulations have been conducted using JSIM simulator setting. In these simulations, sensor nodes are distributed randomly in a 200 200 m setting. The wireless sensor nodes radius is 15 meters and their interference radius is 20 meters. The number of wireless sensor nodes in the conducted simulations varies from 50 to 400 nodes. The nodes energy model in the simulation follows from of JSIM simulator setting energy consumption model. The delay and the consumed power for a MICA2MOTE bit with CC1000 transmitter in different operations are shown in tables 1-4 and 2-4. The presented results are the averages of 20 repetitions of each simulation.
Table I
wireless sensor node parameters in JSIM simulator environment
value Parameters
1Mb
50nJ/bit
5nJ/bit
175 Byte
45 Byte
54000 J Channel band width
Radio electronics
Computer energy for beam forming
Data packet size
Control packet size
Node initial energy
25
Table II
Execution time and consumed energy parameters of MICA2MOTE bit
Power consumption Time
Operation process
90 μW
18 mW
3 mW
45 mW
45 mW
60 mW ---
0.35 ms
1.50 ms
0.25 ms
0.416 ms
0.416 ms Sleep
Radio initialization
Turn on Radio
Switch to RX/TX state
Receive 1 byte
Transmit 1 byte
In the first experiment, the average power consumption of all network nodes is defined in the proposed protocol. The above simulation has been done in networks with different number of nodes. As it is clear of the obtained results by increasing network nodes number, as the message exchange increasing for timing, power consumed by nodes will also increase.
Diagram. 1. The average power consumption of all network nodes in the proposed
protocol
26
Diagram. 2. Execution time of the proposed protocol in networks with different node
numbers
A. Evaluation
In this section we will evaluate and simulate the proposed protocol according to the energy consumption in wireless sensor network nodes. Before simulating the energy consumption model, it is stated that the model is based on.
B. Power consumption in sensor nodes sender-receiver unit
We obtain the power consumption model for wireless sensor network communication subsystems. For this model, the physical connectivity is fixed and is supposed to be B byte per second. In addition, we first suppose that bandwidth is relatively low which we can easily ignore the difference between the interference and transmission using simple protocols without wasting power consumption. Fig.1-4 shows the sender-receiver unit internal structure in a network node as well as the power consumption of each of its components.
27
Figure. 4. A simple class A amplifier circuit
V. Conclusions
In this thesis, the protocols synthetic scheme which increases wireless sensor networks lifetime by regular management. The existing protocols for wireless sensor networks used in different parts of this scheme are a synthetic scheme which effectively minimize the energy consumption throughout the network and reduce the network traffic via data colleting mechanism. This synthetic scheme prevents contact, delay overhead and wasting energy as much as possible and reduce them in order to optimize the network appropriately because of involving the protocols good properties and regular timing.
The energy consumption mathematical analysis in the proposed scheme has been performed by accurate computer simulations. The proposed scheme has been analyzed considering different scales and efficiency evaluation. In conclusion we can conclude that this synthetic scheme is an encouraging solution for solving the contact and interference problem, and increasing networks lifetime.
References
i. Akyildiz IF, Su W, Sankarasubramaniam Y and Cayircl E (2002). A survey on sensor networks. IEEE Communication Magazine, Vol (40), pp 102-114.
ii. Goldsmith AJ and Wicker SB (2002). Design challenges for energy-constrained ad hoc wireless networks. IEEE Wireless Communications, Vol (9), pp 8–27.
iii. Heinzelman W, Kulik J and Balakrishnan H (August 1999). Adaptive protocols for information dissemination in wireless sensor networks. Annual ACM/IEEE International Conference on Mobile Computing and Networking (MobiCom_99), Seattle, WA,
28
v. Panda M and Ranjan Patra M (2010), Modeling radio channels for CSMA-MAC based wireless sensor networks. International Journal of Computer Applications,Vol (9), pp 6-11.
vi. Teng Z and Kim K (2010). A survey on real-time MAC protocols in wireless sensor networks. Communications and Network, Vol (2), pp 104-112.
vii. Chowdhury S and Tauhidul Islam M (2010), Performance analysis of CSMA and IEEE 802.11 in wireless sensor networks using GloMoSim and IEEE 802.11as a Gimmick. International Journal of Computer Science and Network Security, Vol (10), pp 137-143.
viii. Saha D, Yousuf MR and Matin MA (2011). Energy efficient scheduling algorithm for s-mac protocol in wireless sensor network. International Journal of Wireless & Mobile Networks,Vol (3), pp 129-141.
ix. Koteswararao S, Sailaja M, Madhu T, Ramesh P and Rajesh V (2011), Energy aware tdma mac for wireless sensor networks. International Journal of Distributed and Parallel Systems, Vol (2), 103-113.
x. Jandaeng C, Suntiamontut W and Elz N (2011). PSA: The packet scheduling algorithm for wireless sensor networks. International journal on applications of graph theory in wireless ad hoc networks and sensor networks ,Vol (3), pp 1-12.
xi. Atefi K, Sadeghi M and Atefi A (2011). Real-time scheduling strategy for wireless sensor networks O.S. International Journal of Distributed and Parallel Systems,Vol (2), pp 63-78.
xii. Chen Z, Yang G, Chen L,Wang J (2012). An algorithm for data aggregation scheduling with long-lifetime and low-latency in wireless sensor networks.
International Journal of Future Generation Communication and Networking , Vol (5), pp 141-152.
xiii. Taruna S, Kumawat R and Purohit GN (2012). Multi-hop clustering protocol using gateway nodes in wireless sensor network. International Journal of Wireless & Mobile Networks, Vol (4), pp 169-180.
xiv. Patil UA, Modi SV and Suma BJ (2013). A survey: MAC layer protocol for wireless sensor networks. International Journal of Emerging Technology and Advanced Engineering, Vol (3), pp 203-211
xv. Rahmani S, Khademzadeh A and Eftekhari Moghadam AM (2013). Time slot allocation algorithm based on TDMA protocol in wireless sensor networks. Journal of Advances in Computer Research , Vol (4), pp 61-71
xvi. Shubha Rao V and Dakshayini M (2014). A study of QoS aware MAC protocols for wireless multimedia sensor networks. International Journal of Emerging Technology and Advanced Engineering, Vol (4), pp738-744
xvii. Harkut DG, Ali MS and lohiya P (2014). Real-time scheduling algorithms for wireless sensor network. Circuits and Systems: An International Journal, Vol (1), pp
xviii. Pal PK and Chatterjee P (2014). A survey on TDMA-based MAC protocols for wireless sensor network. International Journal of Emerging Technology and Advanced Engineering, Vol (4), pp
29
xx. Zhang M and Wang S (2011). An energy efficient dynamic clustering protocol based on weight in wireless sensor networks. Journal of Networks, Vol (6), pp1057-1064. xxi. Zhang M (2011). An novel energy balanced dynamic routing protocol based on
probability in wireless sensor networks. Journal of Convergence Information Technology, Vol (6), pp 10-17.
