Power Consumption Of Nodes Research Articles

Improving Performance of Distributed Collaborative Beamforming in Mobile Wireless Sensor Networks: A Multiobjective Optimization Method

Mobile wireless sensor networks (MWSNs) are resource constrained, and have limited energy and transmission range. Distributed collaborative beamforming (DCB) in MWSNs based on a virtual node antenna array (VNAA) can increase the transmission distance and enhance the energy efficiency of a single sensor node. To achieve a lower maximum sidelobe level (SLL), sensor nodes can move to optimal locations with optimal excitation current weights for DCB. However, this leads to an extra motion energy consumption. In this article, we construct a multiobjective optimization framework (MOF) to jointly optimize the maximum SLL, transmission power, and motion energy consumption of the DCB nodes in MWSNs. Moreover, an improved nondominated sorting genetic algorithm-II (INSGA-II) and a distributed parallel INSGA-II (DPINSGA-II) are proposed for solving the formulated MOF. In addition, a simple but practical DCB scheduling mechanism is proposed. The simulation results show that the maximum SLL, transmission power, and motion energy consumption of the VNAA can be effectively optimized by the proposed algorithms.

Qualitative-based QoS performance study using hybrid ACO and PSO algorithm routing in MANET

In today’s accelerated growth of mobile device technology, resource utilization in access network will continue to draw more attention to the increasing mobile user devices and applications. The main objective is to address the issue of QoS resource utilization efficiency. This paper combines the Ant Colony Optimization (ACO) algorithm and the Particle Swarm Optimization (PSO) algorithm to provide the optimum routing and to improve the QoS resource utilization efficiency. This proposed hybrid ACO-PSO algorithm uses the IEEE 802.11 DCF standard with multi-antenna scheme (MIMO) of Mobile Ad-hoc Network (MANET) to apply into integrated wireless (MANET) optical (PON network) based in Software Defined Network (SDN) with cloud computing. IEEE 802.11 Wireless Local Area Network (WLAN) gives the opportunity to its users to practice the wireless environment and full functionality of “anything, anytime, anywhere” concept. The proposed work is implemented using the OMNeT++ software where it investigates the QoS performance. These metrics include all nodes throughput, bandwidth, and load balance, routing and control overhead improvement with reduction. They also comprise of RSSI, end to end delay, Packet Delivery Ratio, network capacity, packet loss probability, as well as power consumption in all wireless nodes and energy consumption from wireless domain to wired domain.

A wireless sensor network for high-tech agriculture

This paper presents the design of wireless sensor network (WSN) based on low-power wide area network technology for high-tech agriculture. This WSN allows the farmer to collect data such as air temperature, air humidity, soil moisture. The WSN system consists of components: 02 wireless sensor nodes, 01 gateway, 01 cloud server and smartphone app. This WSN tested for data transmission in two zones: zone 1 (dense urban environments) at a distance of 500m and zone 2 (urban environments - less obstacles) at a distance of 1,500m and 1,700m. The data collected at different times of the day and updated every 15 minutes. The results show that the wireless sensor network system operates stably, data constantly updated to LoRa Server and there was not data packet loss. The power consumption of sensor node and gateway determined in three operating modes: transmitting, receiving, turn-off. This shows the advantages of LoRa technology in the development of wireless sensor network which is the distance of data transmission distance and low power consumption. Besides this WSN also tested in the net house of aquaponics of the Research Center for High-tech Application in Agriculture (RCHAA), University of Science, Vietnam National University-HCM. The results show that the WSN system is working reliably and promising which brings significantly benefits to smart agriculture as aquaponics, clean vegetable farms, aquaculture farms…

An Acoustic Vehicle Detector and Classifier Using a Reconfigurable Analog/Mixed-Signal Platform

The wireless sensor nodes used in a growing number of remote sensing applications are deployed in inaccessible locations or are subjected to severe energy constraints. Audio-based sensing offers flexibility in node placement and is popular in low-power schemes. Thus, in this paper, a node architecture with low power consumption and in-the-field reconfigurability is evaluated in the context of an acoustic vehicle detection and classification (hereafter “AVDC”) scenario. The proposed architecture utilizes an always-on field-programmable analog array (FPAA) as a low-power event detector to selectively wake a microcontroller unit (MCU) when a significant event is detected. When awoken, the MCU verifies the vehicle class asserted by the FPAA and transmits the relevant information. The AVDC system is trained by solving a classification problem using a lexicographic, nonlinear programming algorithm. On a testing dataset comprising of data from ten cars, ten trucks, and 40 s of wind noise, the AVDC system has a detection accuracy of 100%, a classification accuracy of 95%, and no false alarms. The mean power draw of the FPAA is 43 μ W and the mean power consumption of the MCU and radio during its validation and wireless transmission process is 40.9 mW. Overall, this paper demonstrates that the utilization of an FPAA-based signal preprocessor can greatly improve the flexibility and power consumption of wireless sensor nodes.

Energy-Efficient Method for Wireless Sensor Networks Low-Power Radio Operation in Internet of Things

The radio operation in wireless sensor networks (WSN) in Internet of Things (IoT) applications is the most common source for power consumption. Consequently, recognizing and controlling the factors affecting radio operation can be valuable for managing the node power consumption. Among essential factors affecting radio operation, the time spent for checking the radio is of utmost importance for monitoring power consumption. It can lead to false WakeUp or idle listening in radio duty cycles and ContikiMAC. ContikiMAC is a low-power radio duty-cycle protocol in Contiki OS used in WakeUp mode, as a clear channel assessment (CCA) for checking radio status periodically. This paper presents a detailed analysis of radio WakeUp time factors of ContikiMAC. Furthermore, we propose a lightweight CCA (LW-CCA) as an extension to ContikiMAC to reduce the Radio Duty-Cycles in false WakeUps and idle listening though using dynamic received signal strength indicator (RSSI) status check time. The simulation results in the Cooja simulator show that LW-CCA reduces about 8% energy consumption in nodes while maintaining up to 99% of the packet delivery rate (PDR).

Extending the Lifetime of Wireless Sensor Networks using an Improved Clustering Protocol

Wireless Sensor Network (WSN) is one of the underlying mechanics of IoT (Internet-of-Things) which has recently seen a worldwide interest by its use in several domains as military, automation, agriculture, environment, underwater and etc. Energy efficiency and reliability of transmitted messages are two of the major requirements for the surveillance and wireless detection applications in WSN. For this reason, a growing number of research studies are carried out. Several routing protocols have been developed to furnish better performance for optimizing the network's energy consumption in WSN; most of them are based in clustering and hierarchical topology. However, most of these routing protocols cannot consider all required and important metrics to increase the lifespan of the network. This work introduces an enhanced algorithm of the Low Energy Adaptive Clustering Hierarchy (LEACH) protocol called Balanced Current Energy-LEACH (BCE-LEACH) which aims to equity the power consumption of sensor nodes of the network due to extend the lifetime of the network. The proposed protocol is based on the residual energy of sensor nodes to pick out cluster heads (CHs) that means only nodes with sufficient current energy can participate in CH selection, and then it is focused on both current energy and the distance toward the base station (BS) to select a parent CH which has current energy greater than the mean energy of CHs and the distance to the BS is fewer than the average. This parent CH groups all data from other CHs. The root CH after doing data aggregation sends compressed information to the BS using the multi-hop process between CHs. The improved algorithm is simulated in MATLAB R2016b simulation tool. Simulation results in this paper indicate that the introduced protocol works better than LEACH through extending the lifetime of the WSN.

Research on security monitoring system for wind-solar complementary power generation based on internet of things

When traditional system is used to monitor wind-solar complementary power generation, there are problems such as large errors in temperature and wind speed acquired and high power consumption of nodes when the sensor transmits signals. Therefore, a security monitoring system for wind-solar complementary power generation based on internet of things (IoT) is designed. The system hardware is composed of I/O control panel, sensor, GPRS and data processing board. The system software mainly acquires data and processes the acquisition interrupt program. On this basis, the security monitoring of wind-solar complementary power generation is finally realised. The analysis of simulation experiments shows that compared with the traditional system, the data acquisition error of the proposed system is small, which is in good agreement with the actual value. Moreover, the power consumption of nodes is only 15.8 mw when the sensor transmits the signal, indicating that the system has strong reliability and practical application value.

IoT Application Placement Algorithm Based on Multi-Dimensional QoE Prioritization Model in Fog Computing Environment

With the increasing popularity of Internet of Things (IoT) applications in many different areas, the round-trip delay of data processing in the cloud affect the user's quality perception. But fortunately, fog computing aims to service users at the network edge similar to cloud services, which helps in supporting IoT in processing the data near to the end-user, especially for time-sensitive applications. It makes the resource allocation of application placement requests in a fog environment more necessary to satisfy the Quality of Experience (QoE) Influence Factors (IFs). In this paper, an IoT application placement algorithm based on the Multi-Dimensional QoE (MD-QoE) model is proposed in a fog computing environment. The algorithm is composed of two main phases. The first phase is to prioritize different IoT application placement requests depending on three main domains of IFs which are: Environment runtime context, application usage, and user expectations considering the Quality of Service (QoS) violation as a feedback. The second phase is to map and place the request to the appropriate fog node instance, depending on its proximity, computing capabilities, and expected response time. The proposed algorithm is evaluated by simulating a fog environment using iFogSim. Experimental results indicate that the proposed algorithm significantly improves the QoE in respect of application placement time, application delay, network usage, and power consumption. Therefore, the proposed algorithm can improve the overall system performance with a slight increasing in power consumption in fog control nodes.

Performance Evaluation of LoRa ES920LR 920 MHz on the Development Board

This study contains the LoRa ES920LR test on obstruction or resistance conditions and its comparison with Free Space Path Loss (FSPL) using Drone means without obstacles. The ES920LR has 920 MHz frequency channel settings, 125 kHz Bandwidth, and SF 7-12, with 13 dBm Output Power. Comes with Sleep mode operation with Command Prompt based settings. The development board used is a leafony board, Leafony board is a board with a small size that is compatible with Arduino IDE, using a micro ATmega M328P microcontroller, this board is mounted tiled with complete facilities, e.g., a power supply board, four different sensor boards, MCU boards, communication boards e.g., WiFi and Bluetooth, specifically in this article using the LoRa ES920LR on the Leafony board, using LoRa because it requires a long range (km) and low power, and expansion boards that can be developed, Expansion to Leafony boards is expected to reduce the power consumption of the sensor node, lifetime, lif, small size, and lightweight. Furthermore, this algorithm is used to optimize LoRa Coverage and LoRa Lifetime. The results of receiving the FSPL LoRa 920LR have a Power Receiver (Pr) of 30 dB at a distance of 1 meter or A, at 500 meters 85 dB, 1500 meters 95 dB, 2.5km 100 dB. Attenuation is caused by distance, although not significant, other factors are obstacles or obstacles, bad weather (rain, snow).

Wide Field of View Retrodirective Millimeter Wave Antenna Array With Pulse Modulation and Orthogonal Polarization States

This work presents novel techniques to realize a retrodirective millimeter wave antenna array with wide field of view. High gain arrays in phase conjugate configuration are used in combination with orthogonal polarization states and a novel pulse modulation technique to improve backscattering which finds its application in localization and enabling data transmission from sensor nodes. The proposed approach avoids the use of amplifiers thereby reducing the cost, complexity and power consumption of sensor nodes while providing a wide field of view. The basic building blocks of the proposed antenna array are compact one-dimensional (1D) slot arrays that can be designed with orthogonal linear polarizations. Their compact size limits the grating lobes under −10 dB level with respect to the main beam to enable 120° retroreflective field of view, thus, eliminating the reflections in undesired directions while providing 90° rotated linear polarization for the reflected signal with respect to the incident signal polarization. The orthogonal polarization states and compact size are achieved by using a two-layer structure and exploiting the characteristics of substrate integrated waveguide and rectangular cavities. Arrays are designed, prototyped and characterized to validate the proposed concepts. −6pt

Distributed multi-hop routing algorithm for wireless sensor networks

In a Wireless Sensor Network (WSN), routing is the process of finding a cost effective route in terms of power consumption. As an evaluation criterion for the WSN performance, network lifetime is directly affected by the routing method. In a wide variety of WSNs, different techniques are used as routing methods, such as shortest distance path. In this paper, we propose a novel algorithm, optimizing power consumption in WSN nodes, based on the shortest path algorithm. In this approach, the energy level of nodes and their geographical distance from each other contribute to the weight of the connecting path. The proposed algorithm is used as a data dissemination method in WSNs with randomly scattered nodes. We also apply Dijkstra?s shortest path algorithm to the same networks. The results showed that the proposed algorithm increases the network lifetime up to 30 % by preventing nodes with low charge levels from early disconnection.

Centralized MPPT Controller System of PV Modules by a Wireless Sensor Network

An efficient monitoring and control system for solar photovoltaic modules, which combines the use of a non-linear MPPT backstepping controller with a custom wireless sensor network (WSN) has been developed. The infrastructure consists of a wireless smart photovoltaic system (WSPS) and a wireless centralized control system (WCC). The data of sensing, coordination and control is handled by using a WSN based on IEEE 802.15.4 technology in beacon enable mode and with guaranteed time slot. This assures the data transmission and a synchronous acquisition, which are critical elements in a wireless photovoltaic monitoring system. All measured data is gathered by an autonomous, compact and low-cost sensor node installed in each PV module, and it is transferred to the coordinator node. The power consumption of the sensor node represents only 0.25% of the power delivered by the photovoltaic module. A backstepping controller to track the Maximum Power Point (MPP) by means of a buck-boost converter derives the reference parameters to return to each PV module accordingly. The wireless solution uses low latency techniques to achieve a real-time monitoring and a stable performance of the controller. The centralized control identifies all the network nodes and significantly simplifies the maintenance operations. Experimental validation shows the robustness against interference and security in the wireless data transmission and confirms the feasibility of the proposed wireless sensor system in tracking the maximum power transfer under different weather conditions, achieving an efficiency over the 99% in the MPPT.

Research on Low Power Sensor Networking Technology of Transformer Equipment Based on Node Energy

With the development of smart grid and Internet of Things technology, the level of substation intellectualization is getting higher and higher. In order to monitor the substation equipment in real time and obtain the information of equipment operation status, a large number of monitoring sensors are installed on the equipment. Because of the complex internal environment and many dangerous factors in the substation, monitoring nodes usually use wireless communication and rely on their own batteries for power supply. Because the replacement of batteries is not convenient, node power consumption is very important for its lifetime. Traditional monitoring devices install SIM card, but according to this way, the power consumption of the device is large, so it needs to be connected separately to supply power for the device. At present, the main method is to form a network in the station, and the nodes gather information uniformly in the station. Because of the different transmission distance, each node sends information directly, which leads to its own battery consumption too fast, and the generation time of nodes is relatively short. In order to prolong working time and improve energy efficiency, a low-power sensor network technology based on node energy for transformer equipment is proposed in this paper. The energy consumption of each node is balanced by considering the node energy in the process of information transmission, thus prolonging the node lifetime and monitoring the network lifetime.

NEMS Electrostatic RF Wakeup Switch with Pt FIB Contact

Recent pushes to reduce wireless sensor node power consumption have targeted sensors detecting the signal of interest, e.g. acoustic, acceleration, rotation, and use the energy in the signal to trigger switches. Regardless of the sensing modality however, all wireless sensors include some form of data communication radio, which in many cases is constantly consuming power. We take inspiration from a very low sub-threshold current and low switching-energy NEMS switch to implement a near zero-power laterally actuated NEMS electrostatic RF wake-up switch to reduce passive power draw by the RF electronics [1]. The switch is operated by holding a mechanical contact gap just outside of thermal fluctuations and an RF signal acts to physically close the switch. Focused ion beam is utilized to achieve sub-100 nm platinum contact gaps, allowing for below 3V operation and improved reliability. Preliminary results are presented from a custom vacuum probe station utilizing a switch position control loop for the contact-based switch operating off resonance.

A mechanically tunable GHz passive voltage element using microstrip resonator

The ability to detect very low RF signals can be used to wake-up a sensor node only when needed to sense or transmit data, reducing the sensor node power consumption. A passive voltage transforming stage from the antenna to a nano-watt receiver can be useful to reduce the minimum detectable RF signal. At high RF frequencies, the transformer is harder to implement owing to the low impedance of load capacitive loads. We demonstrate a gigahertz frequency range passive voltage transformer, using a mechanically tunable strip-line resonator at 1-2 GHz. The transformer exhibited a 19.5dB gain at 1.007 GHz and achieved gains over 19dB with load capacitances of 0.8-2.4pF. A piezoelectric AlN GHz transducer was also used to measure the gain of the resonator. An RF waveguide model has been developed which matches experiments well for both frequency and gain responses.

An Energy-Efficient Transmission in WSNs for Different Climatic Conditions

Applications of wireless sensor networks (WSNs) are increasing tremendously to facilitate and establish a link between the physical world and information system. The major issues to design such type of WSNs are to reduce the power consumption of sensor nodes and enhance the life-time of nodes having limited battery capacity. In this paper, an energy-efficient transmission scheme in dynamic climatic conditions in WSNs has been proposed. This scheme is IEEE 802.15.4 standard adaptable. It considers two processes one is with feedback and another is without feedback. Process without feedback is used to evaluate and compensate the link quality due to effects of different climatic conditions such as temperature, rain, and snow (dry and wet), albeit process with feedback is used to divide the network into two logical regions to decrease the overhead of control packets. The current number of nodes $$[n_c(t)]$$ and power loss in each region are used to adjust the transmit power level $$(P_{level})$$ of node according to variations in link quality and climatic conditions. Simulation results show that proposed scheme adjusts transmission $$P_{level}$$ to compensate link quality with less packets overhead resulting less energy consumption.

Development of an Energy-Aware Algorithm for Low Power Wireless Sensor Node Powered by Dual Energy Harvesting Sources

A novel self-powered wireless sensor node is proposed and prototyped to overcome the ambient energy lacking in the dual energy harvesting sources by including a secondary energy storage. Moreover, an energy-aware Event-Priority-Driven Dissemination (EPDD) management algorithm has been developed and implemented to control the WSN integrity and reducing the sensor node power consumption as well. EPDD was developed to manage the sensor node operation and to make the sink station able to detect a missing wireless node within the network, which will guarantee the nodes integrity detection. The evaluations revealed that the EPDD shows a good performance in reducing the node power consumption compared to the data push algorithm, whereby, EPDD node was operating 4 hours more than the data push node on the same power source. Regarding the WSN integrity, the EPDD algorithm outpaced the event trigger algorithm, whereby, the EPDD was easily able to detect a node down within the WSN at the contrary of the event trigger.

A Fe–Ga alloy cantilever film vibration harvester with a double-stage signal processing circuit and its main performance testing

With the power consumption of sensor nodes and wireless communication system have been significantly reduced from mW to μW, a new and interesting research field emerges, which is, the power generation technology through harvesting vibration energy from ambient vibration. It might represent a new way to overcome the unsatisfactory battery issue in low-power electronic devices. The aim of this study is on outlining, the basic behavior of a Fe87Ga13 based cantilever harvesting systems. Based on the previous research results in this field, we proposed a cantilever film vibration harvester using Fe–Ga alloy and a double-stage signal processing interface circuit. It was a composite beam structure as a whole in which the Fe–Ga alloy layer and basal layer were closely wound with a pickup coil of wire. The coupling correlation relationship of multi-fields, including mechanical, magnetic and electrical, occurring in the harvester, were analyzed utilizing a distributed-parameter model. Experimental testing were conducted to thoroughly research the main working performance of the harvester which was under the base excitation or transient free excitation, and the main working performances of Fe–Ga alloy based cantilever harvester were obtained clearly. The DC output from the double-stage interface circuit reached to 17.7 V which was far greater than 1.6 V only amplified through a voltage quadrupler rectifier circuit. The prototype succeeded to keep lighting up multi-LEDs, which validated the power generation capability of the prototype and the feasibility of the interface circuit and allowed us to imagine such harvester to supply LED indicators, wireless sensor nodes and other devices with low power consumption.

SocialMANET: A Publish/Subscribe Events Dissemination Protocol for Mobile Ad-Hoc Networks

The popularization of mobile equipment capable of communicating autonomously nowadays offers the possibility of thinking more seriously about a mode of communication in which stakeholders communicate in an ad-hoc manner and use mobility to convey information. However, due to their mobile nature, such equipments are limited by their low energy and storage capacity. Algorithms designed for them must therefore be able to deal with these limitations. In this paper, we present SocialMANET, a distributed publish/subscribe events dissemination protocol for mobile ad-hoc networks. It implements the hierarchical subjects subscription model which, in addition to allowing to formulate refined subscriptions requests close to the content-based subscription model, also permits to minimize the number of subscriptions required to receive events in several topics: to this end, we have proposed a strategy for generating subject identifiers based on the dynamic level numbering technique. Through the use of a dedicated message format that we have defined, SocialMANET minimizes the number of exchanges required between terminals during (fugitive) contacts to detect and respond to their needs by making the best use of the information extracted from these exchanges. This message format, coupled with the concept of lazily altruistic nodes that we propose, allows SocialMANET to guarantee a high rate of events receipt, even in situations where the interests of the network nodes tend to diverge: the results of the simulations conducted show that, compared to other dissemination protocols of the literature, SocialMANET guarantees a better rate of receiving event while minimizing the power consumption of network nodes. We also present in this paper an application prototype for the dissemination of academic informations within a community of students; it’s based on an implementation of SocialMANET.

Performance Analysis of Multiple Relays Cooperative Truncated Automatic Repeat Request in Wireless Sensor Networks

In this paper, we research the performance of direct and non-direct multiple relays cooperative truncated automatic repeat request (D/ND-MRCT-ARQ) protocols in wireless sensor networks (WSNs). We propose a method that named discrete time Markov chain (DTMC) with N + 2 states, which could obtain the throughput formulas of D/ND-MRCT-ARQ protocols. Furthermore, we solve the mathematical expressions of the average transmission delay of both protocols by truncating the number of packet retransmission. In addition, we derive energy efficiency formulas of both protocols under considering the different power consumption of each node. Simulation results demonstrate that the proposed D-MRCT-ARQ protocol achieve higher throughput and energy efficiency while fewer average packet transmission delay, as compared with the ND-MRCT-ARQ protocol.