Wireless Sensor Network Devices Research Articles

Design of a CMOS Monolithic Digitized Light Detector With Noise Insensitivity for Light Monitoring Applications

In this paper, a CMOS monolithic digitized light detector with noise insensitivity for light monitoring applications is newly proposed. The proposed chip is attractive due to the fact that analog processing circuits and light sensor are integrated robustly and compactly. The output signal of the proposed chip is a pulse stream, it could be easily sent over a wide range of transmission media, such as package switch networks, radio, optical, infrared, ultrasonic, and so forth. Unlike previous works, the proposed chip is suitable for processing at a varied light range and also insensitivity to light noise for light monitoring applications. The light range is 15.5 to 2650 lux. All the functions and performance of the proposed monolithic digitized light detector are successfully tested and proven through measurements and confirmed it to be applied on the car-backing monitoring applications. The chip area is 1.998 × 1.616 mm 2 . The proposed chip is suitable for light monitoring devices, such as wireless sensor network devices.

Developing an intelligent control system of automatic window motor with diverse wireless sensor network devices

This invention system involves hardware, firmware and software to develop an intelligent control system of automatic window motor with diverse wireless sensor network (WSN) devices for health and environmental monitoring. The parts of this invention are improved by implementing the WSN mote into environmental sensors that may detect temperature, humility, toxic gas, smog or aerosol, etc. With embedded system design, these sensors are capable of delivering WSN signal packets based on ZigBee protocol that follows the IEEE 802.14.4 standards. The primary hardware of the system is the window motor with circuit design by integrating micro control unit (MCU), radio frequency (RF) and WSN antenna to receive command. The firmware developed under embedded system can bridge hardware and software to control the window at the specified position. At the back end, the control system software can manage diverse sensor data and provide the interface for remote monitoring.

Project Oriented Problem Based Learning: A Wireless Sensor Network Perspective

Every nation rely on latest engineering technologies to foster in today's technological era. Wireless Sensor Networks (WSNs) is one of the latest emerging technologies being the center of interest of today's researchers. All the researchers work hard to produce quick deliverables through Research and Development (RandD) and by applying different learning pedagogues. Currently, the learning pedagogues in Engineering RandD are Project Based Learning and Problem Based Learning (PBL). Based on these pedagogues, this paper propose and implements a hybrid pedagogy called Project Oriented PBL (PO-PBL) which is time effective and result oriented learning pedagogy. It has resulted in providing impetus to RandD in WSNs. Further the proposed pedagogy is divided into two paradigms namely PO-PBL Macro Model and PO-PBL Micro Model. We observed that PO-PBL Macro Model results in optimal number of deliverables in time restricted manner over large scale. Moreover, we have also implemented PO-PBL Micro Model, compared it with PO-PBL Macro Model and propose PO-PBL Micro Model as basis for designing self-learning algorithm for WSNs devices.

Smart Control for Wireless Indoor Lighting System Based on ZigBee Technology

ZigBee is a kind of low rate, low cost and low power technology to be used in cheap, fixed, portable and mobile devices in wireless sensor network. The wireless smart indoor lighting system based on ZigBee technology uses the chip CC2530 as the core. It can collect the light intensity signals of LEDs in real time; perform pulse width modulation (PWM) and wireless communications. The system can also display these parameters on a personal computer such as temperature, light intensity and so on. Even the real-time parameters may be transmitted to the mobile phone to monitor. As a result of the indoor tests that have been conducted, the smart lighting system is more humanized, safe and energy-efficient.

Reducing location error in Wireless Sensor Networks

Localization is the basic problem in the wireless sensor networks. All the result data get wasted if the node is placed in the wrong position. Range based and Range free algorithms are used for locating the node in the wireless sensor network. But in the existing system they will use any one of the algorithm. The method CDL- combined and Differentiated Localization approach inherits the properties of both Range based and Range free algorithm. CDL provides the location accuracy efficiently but still it has location error in large scale networks. To overcome this problem the novel, geographic routing method named Conditioned Mean Square Error Ratio (CMSER) routing, intended to route packets when the localization error is occurred. Keywords: Geographic routing algorithm, Localization, ranging quality, received signal strength indicator (RSSI), wireless sensor network (WSN). I. Introduction A fundamental problem in sensor network is localization identifying the location of nodes. Location information is used to identify the nodes and to route the packets with minimum distance to accurate location. All the sensing data will get waste when the node is placed in the wrong position. The Global Positioning System (GPS) consists many localization approach but they get fails in indoors and under the ground and in forest. Manual configuration is not feasible for large scale networks or networks where the nodes are moving. Providing hardware in all localization is very cost expensive. To locate the node in the wireless sensor network currently two approaches are used for localization. They are Range free and range based approach using RSSI. In practical situation both the algorithm does not able to address the issue of the localization because of dynamic environments. Range-free algorithm takes only network connectivity information and for calculating the distance it use the number of hops between the nodes. The other methods used to calculate the distance between nodes by either using the Time-Of-Arrival (TOA), Time-Differential-Of-Arrival (TDOA), Angle-Of-Arrival (AOA), or Received-Signal-Strength-Indicator (RSSI) technologies. Range based algorithm makes no assumption about the connectivity or availability of the node information in the WSN. Because Range based algorithm have hardware limitations in WSN devices, but the result in range-free localization are being pursued as a cost-effective compared with range-based approaches. To solve the limitations in Range based and Range free algorithm we propose the solution CDL, Combined and Differentiated Localization approach. CDL inherits the advantages of range based and range free algorithm. Initially it calculates distance by using the DV-hop localization algorithm, and then it improving the ranging quality and location accuracy process by double filtration and calibration process. It used to reduce the location error by giving the location accuracy.

TDAL: Thoroughly Data Aggregation of Low Energy Devices in Secure Heterogeneous Wireless Sensor Networks

The heterogeneous wireless sensor networks (HWSNs), composed of multiple types of tiny devices (sensor nodes) with wireless communication capability and suffering from computational resources constrains, enable interacting with the physical world, like never before. Innovative applications are developed for security, industrial production, monitoring, and tracking, but theoretical assumptions on these distributed data may not hold in a real scenario. In this paper, the emphasis is on accurate data and sensor nodes privacy preserving while transmitting their sensory information amongst neighbors toward the sink based on parent-child relationship in the wireless sensor network (WSN) environment, while ensuring energy saving. Data aggregation is a known energy efficient technique that is investigated through in-depth analysis of sensor communication through game theory, considering various embodiments of methods like elliptic curve cryptography for secrecy between nodes. This paper endeavors to provide new perspective for secure and energy efficient data aggregation models, where the heterogeneity of a sensor network environment makes it more complex to predict the overall network outputs.

High-Performance Dispenser Printed MA p-Type Bi0.5Sb1.5Te3 Flexible Thermoelectric Generators for Powering Wireless Sensor Networks

This work presents a novel method to synthesize p-type composite thermoelectric materials to print scalable thermoelectric generator (TEG) devices in a cost-effective way. A maximum ZT of 0.2 was achieved for mechanically alloyed (MA) p-type Bi0.5Sb1.5Te3 (8 wt % extra Te additive)-epoxy composite films cured at 250 °C. A 50% increase in Seebeck coefficient as a result of adding 8 wt % extra Te in stoichiometric Bi0.5Sb1.5Te3 contributed to the increase in ZT. To demonstrate cost-effective and scalable manufacturing, we fabricated a sixty element thermoelectric generator prototype with 5.0 mm × 600 μm × 120 μm printed dimensions on a custom designed polyimide substrate with thick metal contacts. The prototype TEG device produced a power output of 20.5 μW at 0.15 mA and 130 mV for a temperature difference of 20 K resulting in a device areal power density of 152 μW/cm(2). This power is sufficient for low power applications such as wireless sensor network (WSN) devices.

AS-MAC

In many modern advanced Wireless Sensor Network (WSN) applications, the system is expected to deliver intensive traffic loads in harsh RF environment. In this article, an MAC protocol has been proposed which will utilize the adaptive spreading code length technique to increase network performance for these applications. In this architecture, the system can automatically determine the time varying channel quality and set the optimum spreading code length to maximize the throughput while minimizing the energy usage. Due to this adaptive feature, the system is able to deliver reliable wireless service even in the harsh RF environment. The design of such a protocol is also backwards compatible to enable its employment in both traditional and advanced WSN scenarios. Finally, the proposed protocol has been implemented in a COTS WSN platform to obtain the experimental result, which demonstrates the ability of being implemented on typical resource constraints WSN devices. The experimental results have shown the efficiency advantages of the proposed MAC protocol delivering 139% higher throughput as well as having better energy performance than the standard IEEE 802.15.4 system.

Effective Power Consumption Model for the Network Coded Smart Senor Network

realistic power consumption model of wireless communication subsystems typically used in many sensor network node devices is presented. The sensor network facilitates monitoring and controlling of physical environments. These wireless networks consist of dense collection of sensors capable of collection and dissemination of data. They have application in a variety of fields such as military purposes, environment monitoring etc. Typical deployment of sensor network assumes the central processing station or a gateway to which all other nodes for routing data from source to sink using sensor protocol for information via negotiation protocol. Continually sending the data from the natural environment which is necessary needed causes congestion at central station and thus reduces the efficiency of the network results low power life. In this work we will propose a better Sensor Protocol For Information Via Negotiation routing technique using network coding to reduce the total number of transmission and reception in sensor networks resulting in better efficiency as well as power consumption. This power consumption model can be used to guide design choices at many different layers of the design space including, topology design, node placement, energy efficient routing schemes, power management and the hardware design of future wireless sensor network devices.

Designing a Battery-Less Piezoelectric based Energy Harvesting Interface Circuit with 300 mV Startup Voltage

This paper presents a designing a battery-less piezoelectric based energy harvesting interface circuits with 300mV step-up voltage. A technique (i.e., DC-DC Step-Up converter) has chosen for designing the startup voltage with low voltage energy (i.e., 300mV). The proposed method consumes very little power, and is especially suitable for the ambient environmental source, where energy harvested power is very low. The energy harvesting interface circuit consists of MOSFET bridge ac-dc rectifier, voltage regulator, dc-dc step-up converter and an energy storage device with capacitor at the output terminal, replacing this by external battery. This paper will study results these important issues regarding the efficiencies of the energy harvesting power conversion interface circuits considering the storage device low voltage. The achievement of our development circuit is able to boost up minimum 1.67 V for input DC voltage of 300mV. The overall circuit efficiency is greater than 80% following the simulation results. This research has focused on the application of Wireless Sensor Network (WSN) and bio-medical device can be operated without battery.

Natural Synchronization of Wireless Sensor Networks by Noise-Induced Phase Synchronization Phenomenon

SUMMARY We propose a natural synchronization scheme for wireless uncoupled devices, without any signal exchange among them. Our proposed scheme only uses natural environmental fluctuations, such as the temperature or humidity of the air, the environmental sounds, and so on, for the synchronization of the uncoupled devices. This proposed synchronization is realized based on the noise-induced synchronization phenomenon, uncoupled nonlinear oscillators synchronize with each other only by adding identical common noises to each of them. Based on the theory of this phenomenon, the oscillators can also be synchronized by noise sequences, which are not perfectly identical signals. Since the environmental natural fluctuations collected at neighboring locations are similar to each other and cross-correlation becomes high, our proposed scheme enabling synchronization only by natural environmental fluctuations can be realized. As an application of this proposed synchronization, we introduce wireless sensor networks, for which synchronization is important for reducing power consumption by intermittent data transmission. We collect environmental fluctuations using the wireless sensor network devices. Our results show that the wireless sensor network devices can be synchronized only by the independently collected natural signals, such as temperature and humidity, at each wireless sensor device.

Position and Movement Detection of Wireless Sensor Network Devices Relative to a Landmark Graph

We present a novel probabilistic framework for reliable indoor positioning of mobile sensor network devices. Compared to existing approaches, ours adopts complex computations in exchange for high localization accuracy while needing low hardware investment and moderate set-up cost. To that end, we use full distributional information on signal measurements at a set of discrete locations, termed landmarks. Positioning of a mobile device is done relative to the resulting landmark graph and the device can be found near a landmark or in the area between two landmarks. Key elements of our approach include profiling the signal measurement distributions over the coverage area using a special interpolation technique; a two-tier statistical positioning scheme that improves efficiency by adding movement detection; and joint clusterhead placement optimization for both localization and movement detection. The proposed system is practical and has been implemented using standard wireless sensor network hardware. Experimentally, our system achieved an accuracy equivalent to less than 5 meters with 95 percent success probability and less than 3 meters with an 87 percent success probability. This performance is superior to well-known contemporary systems that use similar low-cost hardware.

Leveraging Height in a Jumping Sensor Network to Extend Network Coverage

With respect to ground level, wireless communication signal strength increases with the elevation of communicating wireless sensor network devices, within practical bounds. Jumping sensors are mobile sensors that provide relocation capabilities and a temporary increase in elevation can be utilized for improving communication. This paper provides a comprehensive multidimensional analysis for jumping sensors. It studies the main factors that impact the Received Signal Strength (RSS) in sensor communication, and performs a comparative analysis between theoretical and experimental results. Sensor elevation from ground level is a key factor, which is often neglected, and plays an important role for successful wireless communication. The impact of jump height manipulation on a jumping sensor to the packet transmission goodput is presented. An airborne two-way communication scheme is defined and studied with experiments. The results indicate the effectiveness of utilizing the change in elevation of a jumping sensor to increase communication range. Since energy is at premium in sensor nodes, the operational energy cost of a jumping sensor prototype is studied in detail. A jumping sensor network is simulated with the parameters learned from the experimental results and the jumping sensor prototype analysis. Simulation results show the enhancement in connectivity and the feasibility of a jumping sensor network.

기밀문서유통을 위한 Weil Pairing IBE 개선 연구

PKI에 기반을 둔 공개키 방식은 인증성과 비밀성에서 뛰어난 반면 적용된 시스템에서 인증서와 키 관리는 큰 부담이다. 또한 암복호 복잡도(complexity)가 크기 때문에 WSN(Wireless Sensor Network)의 제한된 컴퓨팅 장치에서는 사용하기가 어렵다. 이에 키관리 부담을 없앤 IBE(ID Based Encryption) 방식에서 Bilinear Pairing 방식은 수행속도가 뛰어나고 충분히 안전한 DDH(Decisional Diffie Hellman) 알고리즘으로 인/검증을 처리하는 차세대 암호방식이다. Bilinear Pairing의 이론을 구현한 Elliptic Curve Weil Pairing의 알고리즘은 단순하고 CCA(공격)에 IND/NM의 강력한 보안조건을 만족한다. 동작측면에서 Random Oracle Model을 가정한 IBE PKG는 단일 기밀문서 파일서버로 작동하는 우리의 목적 시스템의 구조에 적합하다. 따라서 본 논문는 Weil Pairing Based IBE 방식을 폐쇄적 기밀문서 유통망[2]에 적합하도록 암복호 및 인검증 알고리즘을 개선하고 본 유통망에 적용된 효율적 프로토콜을 제안한다. 본 논문은 먼저 암호화, 무결성 그리고 사용자 인증을 O(DES) 수준으로 수행하는 개선된 알고리즘을 제안하며 한 번의 암호화 처리에서 비밀성, 무결성과 인증성을 달성하는 정보를 암호문에 포함된다. 둘째 PKI 인증서의 효과를 가진 공개 식별자를 적용하여 키 노출의 위험을 줄인 개선된 IBE 방식을 제안한다. PKI-based public key scheme is outstanding in terms of authenticity and privacy. Nevertheless its application brings big burden due to the certificate/key management. It is difficult to apply it to limited computing devices in WSN because of its high encryption complexity. The Bilinear Pairing emerged from the original IBE to eliminate the certificate, is a future significant cryptosystem as based on the DDH(Decisional DH) algorithm which is significant in terms of computation and secure enough for authentication, as well as secure and faster. The practical EC Weil Pairing presents that its encryption algorithm is simple and it satisfies IND/NM security constraints against CCA. The Random Oracle Model based IBE PKG is appropriate to the structure of our target system with one secret file server in the operational perspective. Our work proposes modification of the Weil Pairing as proper to the closed network for secret file distribution[2]. First we proposed the improved one computing both encryption and message/user authentication as fast as O(DES) level, in which our scheme satisfies privacy, authenticity and integrity. Secondly as using the public key ID as effective as PKI, our improved IBE variant reduces the key exposure risk.

Integration of IoT and DRAGON-lab in cloud environment

Distributed research & academic gigabits open network lab (DRAGON-lab) is the only test-bed for research purpose related to next generation internet (NGI) which based on the confederation network using three layers cloud structure. As an essential part of NGI, the research related to the Internet of things (IoT) devices should be applied on the DRAGON-lab platform. This paper proposes an approach to converging the IoT devices to confederation network by integrating each layer of cloud structure between DRAGON-lab and IoT. This research activity extends the use of DRAGON-lab, makes the IoT and wireless sensor network (WSN) devices working well in the confederation network. It was also a foundational research for three layers cloud structure, which could be reused for other related research. Finally, it finishes the preparation work for IoT internet protocol version 6 (IPv6) devices research in DRAGON-lab, which is essential for the NGI.

Performance Evaluation of Indices-Based Query Optimization from Flash-Based Data Centric Sensor Devices in Wireless Sensor Networks

Flash memory has become a more widespread storage medium for modern wireless devices because of its effective characteristics like nonvolatility, small size, light weight, fast access speed, shock resistance, high reliability, and low power consumption. Sensor nodes are highly resource constrained in terms of limited processing speed, runtime memory, persistent storage, communication bandwidth, and finite energy. Therefore, for wireless sensor networks supporting sense, store, merge, and send schemes, an energy efficient and reliable database-based query optimization technique is highly required with consideration of sensor node constraints. Databases on hard disk drives perform data storage and retrieval using index structures which are still not practiced for sensor devices. In this paper, we evaluate different indices like B-tree, R-tree, and MR-tree by implementing them on log structured external NAND flash memory-based advanced file systems for supporting energy efficient data storage and query optimization from flash based data centric sensor devices in wireless sensor networks. Experimental results show that PIYAS (Rizvi and Chung, 2010) file system along with B-tree indexing deployed on flash memory MLC gives the significant performance in respect of high query throughput optimization and less resources consumption for wireless sensor devices.

Building lighting automation through the integration of DALI with wireless sensor networks

This paper focuses on the integration of Digital Addressable Lighting Interface (DALI) devices in wireless sensor networks. Since different manufacturers usually deal with one aspect of building automation - e.g. heating ventilation and air conditioning, lighting control, different kinds of alarms, etc. - final building automation system has different subsystems which are finally taken to an integrated building management system. The cost of this process is consequently increased due to additional hardware investment. Our main purpose is to provide the end consumer with an economical fully centralized system in which home appliances are managed by an IEEE 802.15.4-based wireless sensor network. Not only is it necessary to focus on the initial investment, but maintenance and energy consumption costs must also be considered. This paper explains the developed system along with a brief introduction to usual building automation protocols. Finally it presents future work in this field.

Designing of Foot Imbalance Scanning System

In this paper, a low cost mobile foot pressure scanning device has been developed which has linked with the Wireless Sensor Networks (WSN) for continuous monitoring of human foot plantar-pressure. The device was attached to test subjects who then went through a regimen of varied walking, jumping and turning action on the ground. Data was collected simultaneously through WSN device. In this project, the hardware and software system have been developed for detecting, collecting, transmitting and finally analyzing the collected data. To estimate the peak pressure points on the foot sole, several experiments were conducted.

Power-Management Techniques for Wireless Sensor Networks and Similar Low-Power Communication Devices Based on Nonrechargeable Batteries

Despite the well-known advantages of communication solutions based on energy harvesting, there are scenarios where the absence of batteries (supercapacitor only) or the use of rechargeable batteries is not a realistic option. Therefore, the alternative is to extend as much as possible the lifetime of primary cells (nonrechargeable batteries). By assuming low duty-cycle applications, three power-management techniques are combined in a novel way to provide an efficient energy solution for wireless sensor networks nodes or similar communication devices powered by primary cells. Accordingly, a customized node is designed and long-term experiments in laboratory and outdoors are realized. Simulated and empirical results show that the battery lifetime can be drastically enhanced. However, two trade-offs are identified: a significant increase of both data latency and hardware/software complexity. Unattended nodes deployed in outdoors under extreme temperatures, buried sensors (underground communication), and nodes embedded in the structure of buildings, bridges, and roads are some of the target scenarios for this work. Part of the provided guidelines can be used to extend the battery lifetime of communication devices in general.

Visualisation of efficiency coverage and energy consumption of sensors in wireless sensor networks using heat map

A wireless sensor network (WSN) consists of spatially distributed autonomous sensors that cooperatively monitor physical or environmental conditions such as temperature, sound, vibration, pressure, motion and pollutants. WSNs are currently utilised in various and different types of WSN simulators have been developed to visually depict the coverage, energy consumption status and expected lifetime of WSN sensors. In particular, owing to the importance of low energy movement design for efficient energy consumption, devices that can design and verify the efficiency of packets are being developed. Therefore, this study suggests a coverage visualisation technique for a sensor node; this technique is based on an existing binary model that uses the detection rate of nodes portrayed on a heat map. In addition to coverage visualisation, the visualisation technique can be used to predict the energy lifetime of a node. The simulator that can verify visualisation techniques for efficient coverage visualisation and energy lifetime prediction has been designed and implemented. This simulator, which the authors have named current reduction state observer on WSN device (CROWD), performs sensor network simulation using a virtual sensor network and multi-mobile objects. CROWD also shows the detection rate of sensors on a heat map.