Low Duty-cycled Wireless Sensor Research Articles

Effective neighbor node discovery using improved Bayesian clock synchronization‐gossip routing protocol in mobile low duty cycle wireless sensor network

AbstractIn wireless application, mobile low duty cycle wireless sensor network (MLDC‐WSN) gained more attention among the researchers, because it includes advantages like growing node life, saving node power, and network reliability. However, the sleeping features and mobility of MLDC‐WSN results in topology change that restricts the speed of neighbor node discovery. To highlight this concern, a novel routing protocol named as improved Bayesian clock synchronization‐gossip routing protocol is proposed for an effective neighbor node discovery in MLDC‐WSN. The proposed routing protocol reduces end‐to‐end delay, and clock drifts problems. Also, the proposed routing protocol improves the clock synchronization and captures the neighbor discovery nodes by identifying the next neighbor set in the next moment, due to the prediction of the distance and movement speed of neighbors. Simulation and analytical results showed that the proposed routing protocol superiorly decreases the end‐to‐end delay and energy consumption compared to the existing algorithms.

WITHDRAWN: A survey on continuous neighbor discovery for mobile low duty cycle wireless sensor network

Abstract In the network implementation point, neighbourhood exploration is a very significant phenomenon. However, due to the complex existence of WSN and the probability of adding new nodes and withdrawing nodes from the network, continuous exploration of neighbours is required. It does suggest that the identification of neighbours is not a one-time operation. There are also benefits of WSN for the identification of neighbours. In addition to saving node power and growing node life, network reliability is increased. The analysis of the literature in this paper gives valuable insights into the latest state of the art in continuous exploration of neighbours in WSN. In specific, it reflects on the WSNs of the low duty mobile cycle. The analysis holes found in the literature are also given.

Bi-adjusting duty cycle for green communications in wireless sensor networks

Green communications is a challenging issue for communications and networking. In order to save energy, nodes of the wireless sensor networks (WSNs) usually adopt the low duty cycle mode which brings a large delay to the event detection and data transmission to the sink and deteriorates the network’s timely processing of the event. In this paper, bi-adjusting duty cycle schedule (BADCS) scheme is proposed to reduce event detection latency as well as data routing delay for low duty cycle wireless sensor networks. BADCS scheme consists mainly of two duty cycle adjustment algorithms: (a) active slot asynchronous adjustment algorithm for nodes in the same sensing area; (b) the continuous adjustment algorithm for two adjacent nodes on the routing path with one active slot interval. Specifically, the operations are 2-fold. First, perform asynchronous operations on the active slots of the nodes in the same sensing area, so that the active slots of the nodes in the same sensing area are distributed as evenly as possible without overlapping. In this way, it is possible to reduce the latency by the time the event is perceived after its occurrence. Secondly, active slots of the nodes on the routing path are adjusted to be with pipeline style, so that when the nodes receive the data packet, they can route through the continuous active slots, thus greatly reducing the delay of data routing. Two adjustment algorithms of active slot are given in detail in this paper. The performance of BADCS mode is discussed in detail, and its performance is better than the previous strategy. Comprehensive experiments are conducted, and the results demonstrate that the proposed BADCS scheme significantly improves event detection performance in terms of detection latency, detection probability, and routing delay. Detection delay and routing delay are reduced as high as 3.91% and 56.22% respectively.

Minimizing Delay and Transmission Times with Long Lifetime in Code Dissemination Scheme for High Loss Ratio and Low Duty Cycle Wireless Sensor Networks.

Software defined networks brings greater flexibility to networks and therefore generates new vitality. Thanks to the ability to update soft code to sensor nodes, wireless sensor networks (WSNs) brings profound changes to Internet of Things. However, it is a challenging issue to minimize delay and transmission times and maintain long lifetime when broadcasting data packets in high loss ratio and low duty cycle WSNs. Although there have been some research concerning code dissemination, those schemes can only achieve a tradeoff between different performances, instead of optimizing all these important performances at the same time. Therefore, in this paper we propose a new strategy that can reduce delay and transmission times simultaneously. In traditional method, the broadcasting nature of wireless communication is not sufficiently utilized. By allowing sons of the same parent node to share awake slots, the broadcasting nature is well exploited and delay is thus reduced as well as transmission times with lifetime not affected. And, as we discover there is energy surplus when collecting data in area away from sink, we further improve this strategy so that all the performances can be further bettered. Compared with traditional method, the methods we design (IFAS, BTAS and AAPS) can respectively reduce delay by 20.56%, 31.59%, 55.16% and reduce transmission times by 29.53%, 43.93%, 42.04%, while not reducing lifetime.

Data Collection Strategy in Low Duty Cycle Wireless Sensor Networks with Mobile Sink

The lifetime of wireless sensor networks can be improved by imposing low duty cycle, but doing so could not solve unbalanced energy consumption and will increase transmission latency. To avoid this, this paper gives a new method to collect data by mobile sink. The proper data collection route is selected according to the sink speed and buffer size of the sensors. The sensors only wake up when the sink approaches them. When certain sensors detect an emergency, the sink catches the message quickly and moves to the hotspot to decrease message relay in the network. The result of simulation by OPNET shows that this protocol can reduce transmission data in the network and prolong the network lifetime.

Scheduling Scheme based on Estimated-delay in Wireless Sensor Network

In the low duty cycle wireless sensor network with unreliable link quality, how to meet designated delay requirements and maximize network lifetime is the focus of this study. This paper proposes the Scheduling Scheme based on Estimated-delay(SSE), which could satisfy decreasing energy consumption as well as delivery delay in the low duty cycle wireless sensor network by utilizing the estimated-delay from the current node to the destination node. We compare our SSE algorithm with other algorithms in the simulation. The results show that SSE could significantly improve the performance in the low duty cycle wireless sensor network compared with other algorithms at the same required delay. This paper studies the Node Scheduling Scheme in wire- less sensor network, and then proposes Scheduling Scheme based on Estimated-delay (SSE) under unreliable link quality in low duty cycle wireless sensor network. As we know, in wireless sensor network, nodes energy is major consumed in the transmission work slot (2), with the ability of computing in each node, the node could predict the delivery delay be- tween it and the destination node, then select a path from it to the destination node based on the least delay. During the transfer process, each node could predict new delay based on this path to the destination node and dynamically adjust it's work slot according to it's energy as well as the required delivery delay to the destination node. Based on this, we design the Scheduling Scheme for low duty cycle wireless

Trade-Offs between Energy Saving and Reliability in Low Duty Cycle Wireless Sensor Networks Using a Packet Splitting Forwarding Technique

One of the challenging topics and design constraints in Wireless Sensor Networks (WSNs) is the reduction of energy consumption because, in most application scenarios, replacement of power resources in sensor devices might be unfeasible. In order to minimize the power consumption, some nodes can be put to sleep during idle times and wake up only when needed. Although it seems the best way to limit the consumption of energy, other performance parameters such as network reliability have to be considered. In a recent paper, we introduced a new forwarding algorithm for WSNs based on a simple splitting procedure able to increase the network lifetime. The forwarding technique is based on the Chinese Remainder Theorem and exhibits very good results in terms of energy efficiency and complexity. In this paper, we intend to investigate a trade-off between energy efficiency and reliability of the proposed forwarding scheme when duty-cycling techniques are considered too.