Earned Value Analysis for real time wireless sensor network

The previous work on connection driven topology control has shown that it has significant potential to reduce energy consumption of Wireless Sensor Networks (WSNs). Dynamic Modulation Scaling (DMS) which is a technique that manages transmission power levels in order to change the number of bits encoded per symbol has a direct impact on connection driven topology control. In this paper we investigate the transmission scheduling of multi-hop real-time WSNs equipped with DMS enabled radio chips while taking the effect of DMS on topology control into account. To our best knowledge, this is the first paper that addresses this issue. The current work on DMS enabled WSN tend to rely on theoretical DMS models to predict network performance metrics. However, there is little, if any, work that is based upon empirically verified network performance outcomes using DMS especially on its effect on connection driven topology control. This paper fills this gap by using GNU Radio and Software Defined Radio hardware to show how to emulate DMS in low power wireless systems and measure the impact of varying Signal-to-Noise levels, distance and elevation on throughput and delivery rates for different DMS control strategies. Next, we present the Mixed Integer Nonlinear Optimization Problem of minimizing energy consumption of DMS enabled connection driven topology control on real-time WSNs. Lastly, we present two polynomial time heuristics and compare their performance against the optimal solution.

In order to gather information more efficiently, wireless sensor networks (WSNs) are partitioned into clusters. The most of the proposed clustering algorithms do not consider the location of the base station. This situation causes hot spots problem in multi-hop WSNs. Unequal clustering mechanisms, which are designed by considering the base station location, solve this problem. In this paper, we introduce a fuzzy unequal clustering algorithm (EAUCF) which aims to prolong the lifetime of WSNs. EAUCF adjusts the cluster-head radius considering the residual energy and the distance to the base station parameters of the sensor nodes. This helps decreasing the intra-cluster work of the sensor nodes which are closer to the base station or have lower battery level. We utilize fuzzy logic for handling the uncertainties in cluster-head radius estimation. We compare our algorithm with some popular algorithms in literature, namely LEACH, CHEF and EEUC, according to First Node Dies (FND), Half of the Nodes Alive (HNA) and energy-efficiency metrics. Our simulation results show that EAUCF performs better than the other algorithms in most of the cases. Therefore, EAUCF is a stable and energy-efficient clustering algorithm to be utilized in any real time WSN application.

Barrier coverage is widely used in border surveillance. Most literatures only consider sensing in barrier coverage. In this paper, we consider not only sensing but also communication in barrier coverage under a more practical environment: multi-hop wireless sensor networks. We assume that each sensor has k+1 adjustable sensing power levels and k+1 adjustable transmission power levels. Sensing data should be aggregated and transmitted to the sink node within a latency constraint. We call minimizing the individual node’s maximum energy cost for barrier coverage subject to the latency constraint as the MIME problem. We propose several algorithms to solve the MIME problem. Firstly, we devise a distributed algorithm to minimize the sensing energy cost 1-local barrier coverage, then we use Divide and Conquer method to construct none-crossing k-barrier coverage. Finally we devise a heuristic algorithm to construct a data aggregation tree that satisfies nodes in barriers transmitting data to the sink node within the latency constraint. Simulations show that the proposed algorithms are efficient and outperform other existing algorithms.

Energy efficient and reliable data forwarding becomes important if resources are limited such as in Wireless Sensor Networks. In this paper, we discuss how the error rate associated with a link affects the overall probability of reliable delivery, and consequently the energy associated with the reliable transmission of a single packet. The analysis includes both fixed-power and variable-power scenarios along with the End-to-End Retransmission (EER) and Hop-by-Hop Retransmission (HHR) techniques. In the EER case, a threshold value for the packet error rate at which both scenarios will result in the same energy costs is defined. The relation between this threshold value and the difference in number of hops between both scenarios is also derived. The simulation results finally confirm the theoretical model.

Wireless sensor networks (WSNs) are often deployed in harsh environments with little human control, thereby necessitating self organizing and maintenance mechanisms for medium sharing and data routing. Moreover, since sensor nodes operate on energy-limited batteries, designing energy-efficient routing techniques that extend the network lifetime is of a paramount importance. In this paper, we propose WCDS-DCR, a fully distributed, data-centric, routing technique that makes use of an underlying clustering structure induced by the construction of WCDS (Weakly Connected Dominating Set) to prolong network lifetime. WCDS-DCR aims at extending network lifetime through the use of data aggregation (based on the elimination of redundant data packets) by some particular nodes. It also utilizes both the energy availability information and the distances (in number of hops) from sensors to the sink in order to make hop-by-hop, energy-aware, routing decisions. Simulation results show that our solution is scalable, and outperforms existing schemes in terms of network lifetime.

Energy efficiency is critical in wireless sensor networks (WSN) for system reliability and deployment cost. The power consumption of the communication in multi-hop WSN is primarily decided by three factors: routing distance, signal interference, and computation cost of routing. Several routing algorithms designed for energy efficiency or interference avoidance had been proposed. However, they are either too complex to be useful in practices or specialized for certain WSN architectures. In this paper, we propose two energy efficient geographic routing algorithms (EEGRA) for wireless sensor networks, which are based on existing geographic routing algorithms and take all three factors into account. The first algorithm combines the interference into the routing cost function, and uses it in the routing decision. The second algorithm transforms the problem into a constrained optimization problem, and solves it by searching the optimal discretized interference level. We integrate four geographic routing algorithms: GOAFR+, Face Routing, GPSR, and RandHT, to both EEGRA algorithms and compare them with three other routing methods in terms of power consumption and computation cost for the grid and irregular sensor topologies. The results of our experiments show both algorithms conserve sensor's routing energy 30% ~ 50% comparing to general geographic routing algorithms. In addition, the time complexity of EEGRA algorithms is similar to the geographic greedy routing methods, which is much faster than the optimal SINR-based algorithm.

Wireless industrial sensor networks are wireless sensor networks which have been adapted to industrial applications. Most techniques for wireless sensor networks can be applied to wireless industrial sensor networks. However, for industrial applications of wireless industrial sensor networks, new requirements such as real-time, reliable delivery need to be considered. In this paper, we propose EARQ, which is a novel routing protocol for wireless industrial sensor networks. It provides real-time, reliable delivery of a packet, while considering energy awareness. In EARQ, a node estimates the energy cost, delay and reliability of a path to the sink node, based only on information from neighboring nodes. Then, it calculates the probability of selecting a path, using the estimates. When packet forwarding is required, it randomly selects the next node. A path with lower energy cost is likely to be selected, because the probability is inversely proportional to the energy cost to the sink node. To achieve real-time delivery, only paths that may deliver a packet in time are selected. To achieve reliability, it may send a redundant packet via an alternate path, but only if it is a source of a packet. Experimental results show that EARQ is suitable for industrial applications, due to its capability for energy efficient, real-time, reliable communications.

Wireless sensor networks (WSN) has been extensively used in many real time wireless sensor networks applications. Due to limitations of hardware resources and restricted communication capabilities of sensor nodes, it is very challenging to use wireless sensor networks in real time data transmission. Data collection and routing is the main issue in such applications. To enhance the performance under such real time transmission scenario, it is essential to make the protocol intelligent to choose the appropriate path with change in network scenario. Now a days, many machine learning and deep learning algorithms are used for improving the real time data transmissions in WSNs. From the survey on existing methods, it is clear that using machine learning makes the computational methods more reliable, powerful and economical. This paper proposes a machine learning based Medium Access Control (MAC) protocol to handle real time traffic in wireless sensor networks. To deal with the limitations of WSN in real time application, the proposed scheme can help to increase the performance of time-critical wireless sensor network applications. Simulation results authorize our work and confirm the accuracy of the proposed ML-MAC protocol strategy is higher than the existing work.

In this paper, we propose the effective analysis methodology to be applied to the monitoring network of synchronous under the IEEE 802.15.4 standard, we call it real-time wireless sensor network (RT-WSN) in this network that is build for the “real-time” specific application. We aim at the slotted Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) of algorithm of channel access mechanism in IEEE 802.15.4 MAC layer to build the network model and analyze the average packet delay over RT-WSN based on probability theory. The proposed theoretical analysis was nearly consistent with the correct result of simulation and the experiment. The result shows that this slotted CSMA/CA cannot be effectively applied to RT-WSN since it cannot avoid the high packet collision in the saturation throughput conditions. When receiving 10 sensor nodes, the packet delay caused by packet collision is 6.29 times more than one ideal model. Hence, we propose the like Time Division Multiple Access (TDMA) to improve CSMA/CA in packet collision problem. With neighbor table, TDMA can record the network states and implement the dynamic network configuration. Our experimental results show that TDMA can own the characteristics of the stable and limited packet delay. Once the total traffic load is lower than maximum throughput, it can guarantee the packet transmission of real-time without considering the amount of sensor nodes in network. Moreover, compare with CSMA/CA in 10 sensor nodes conditions, 57 % of the maximum throughput is improved. Therefore, we can meet with the QoS requirement of packet delay in RT-WSN. In the end, we install a remote ECG monitoring system for an example of application situation in the sanatorium. We provide steady wireless transmission media for the front of this system and reach the purpose of real-time remote medical care.

Energy minimization by exploiting data redundancy in real-time wireless sensor networks

New security approach in real-time wireless multimedia sensor networks

Wireless Sensor Networks (WSNs) are fundamental to security and surveillance applications such as military defense, disaster management, and intrusion monitoring. The performance of these networks depends largely on the efficiency of routing protocols. This paper examines the Ad hoc On-Demand Distance Vector (AODV) routing protocol in multi-hop WSN environments for target tracking, evaluating critical metrics including Packet Delivery Ratio (PDR), End-to-End Delay, Energy Consumption, and Network Lifetime. Simulation results illustrate the impact of node depletion due to transmission loss, affecting network stability and robustness in target detection. In-network detection in WSNs presents trade-offs between real-time data transmission, energy efficiency, and trajectory lifespan. Inefficient routing optimization may result in increased latency, packet loss, and premature node failure, ultimately reducing localization accuracy. While AODV’s reactive path-based approach offers manageable overhead, its performance degrades under increased energy consumption and route rediscovery delays. This study systematically evaluates AODV’s strengths and limitations in time-sensitive detection scenarios. Findings indicate that AODV ensures reliable data transmission in early network stages but suffers significant performance deterioration as node energy declines, impacting coverage and responsiveness. To enhance AODV’s target tracking capabilities, this paper proposes adaptive energy-saving techniques and hybrid routing schemes. These strategies contribute to ongoing research aimed at optimizing routing protocols to balance accuracy and node longevity for real-time WSN applications.

The wireless sensor networks (WSNs) are among most widely used technology that can change the future. Improvement in WSN has made to replace thousands of wires connected to medical devices used in hospitals and providing mobility and reliability. The lifetime of the sensor network is less because the sensor nodes run on batteries which must be efficiently utilized. Many protocols do not take route into consideration which is efficient in terms of energy, power consumption and can improve the overall network lifetime. Dual hop routing using LoCoDuo protocol was used to improve network lifetime which consumes low power for transmission of data and dual buffer mechanism was used to avoid congestion in the network. The route from source to sink is found by the proposed method and compared it with LEACH protocol. The test results show that the performance of the proposed system is improved compared to that of LEACH protocol. The algorithm is validated for various evaluation metrics such as energy consumption, number of hops and number of dead nodes. The proposed system performs better in all cases which results in increase in the network lifetime. Compared to single buffer threshold policy number of packets remaining is less in dual buffer threshold policy which results in avoiding congestion in the network.

Wireless Sensor Network (WSN) is one of the active research topics in the field of computer network since it provides three types of basic services: sensing, processing, and disseminating. Ad-hoc and multi-hop WSNs are commonly used in many applications; therefore, maintaining stability of WSN is an essential issue in present days. However, node failures are not exceptions in WSN. Many factors may cause sensor nodes to fail, such as energy exhaustion, out of communication range, or node module damage. These damages are usual incidents in practical WSN applications. Except node module damages that we are unable to look after, we propose an energy-efficient routing algorithm to prolong the lifetime of nodes in WSN. Another feature of the proposed algorithm is that each node routes network packets independently throughout the entire WSN. It makes that algorithm to provide autonomic management of the links in WSN.

One of the major challenges in wireless sensor networks (WSNs) deployment is to decrease sensor node's energy consumption to prolong the lifetime of the finite-capacity batteries. Using multihop has been viewed as one of the main techniques to prolong operational lifetime in wireless sensor networks. In this paper we offer a study on transmission power control (TPC) in multihop WSNs using typical Telosb platform parameters, which is IEEE 802.15.4 standard compliant. We offer a new approach to test TPC in multihop networks at the physical layer and provide energy consumption performance results via simulation and numerical model in multihop WSNs. Our simulation and numerical model results illustrate that energy spent to send packets using short-range multihop path instead of single hop does not necessarily save energy as suggested by some of the earlier research.