This paper presents a fault-tolerant (fault tolerant) can enhance the communications capabilities, improve the reliability and efficiency of in smart grid signal transmission. Meter layout with PLC or ZigBee in any topology, meter adopt Minimum Spanning Tree algorithm to achieve shortest distance and lost cost in PLC; when device contain wireless receiver, meter adopt Hungarian algorithm can search nearest itself¡¦s device to receive device information. The paper propose two fault tolerant methods: static and dynamic methods. Static method is a meter transmit to another one with regular communication even if a meter tranfmit with ZigBee; dynamic method is a meter transmit another one, ZigBee has low priority according to cost function in effective communication range. The paper simulation in any 100m2 topology, randon produce 13 SmartUnit with different number of meters and coordinate, two fault tolerant method can achieve 100% fault coverage in single link fault case; but static method use FTGDB(Fault Tolerant Generalized De Bruijn algorithm) multiple fault coverage can achieve 43% with d=4 case; dynamic method use Kth shortest path algorithm multiple fault coverage can achieve 61% with d=4 case. In other words FTGDB has average 100 communication line allow average 43 communication line fault tolerant ability with d=4 case in 13 SmartHomeUnit; Kth shortest path algorithm has average 100 communication line allow average 61 communication line fault tolerant ability with d=4 case in 13 SmartHomeUnit. If after fault tolerant achievement, count to demand energy and delay time with PLC and ZigBee, then it can offer electric company information. Electric company evaluate electric cost¡Breal time price etc¡K The paper propose a online demand response method, the method is Online Priority Tree algorithm to be counted end device¡¦s rank priority according to device importance.

The frequency synthesizer, which performs the main role of carrier generation for the down-conversion/up-conversion operations, is a key building block in radio transceiver front-ends. The design of a synthesizer for a 2.4 GHz IEEE 802.15.4/Zigbee transceiver forms the core of this work. This thesis provides a step-by-step procedure for the design of a frequency synthesizer in a transceiver environment, from the mapping of standard-specifications to its integrated circuit implementation in a CMOS technology. The results show that careful system level planning leads to high-performance realizations of the synthesizer. A strategy of using different supply voltages to enhance the performance of each building block is discussed. A section is presented on layout and board level issues, especially for radio-frequency systems, and their effect on synthesizer performance. The synthesizer consumes 15.5 mW and meets the specifications of the 2.4 GHz IEEE 802.15.4/Zigbee standard. It is capable of 5 GHz operation with a VCO sensitivity of 135 MHz/V and a tuning range of 700 MHz. It can be seen that the adopted methodology can be used for the design of high-performance frequency synthesizers for any narrow-band wireless standard.

In this thesis, we propose a personal gateway for wireless body area network(WBAN). By using wireless communication and a proper WBAN topology, patients¡¦ physiological signal could be recorded without restricting their mobility. Moreover, integration of several kinds of signals from different sensor nodes in one data platform, personal gateway (PG), can reduce the redundant hardware of individual links as well as the complexity of WBAN. A device for long-term bladder urine pressure measurement is designed as a sensor node of PG. Not only is the design cost reduced, but also the reliability is enhanced by using a 1-atm canceling sensing IA (instrumentation amplifier). Because the urine pressure inside the bladder does not vary drastically, both the sleeping and working modes are required to save the battery power for the long-term observation. To integrate circuits with different supply voltages in PG, a 0.9/1.2/1.8/2.5/3.3/5.0 V wide-range I/O buffer carried out using a typical CMOS process is designed. An input buffer with a logic calibration circuit is used for receiving a low voltage signal. A novel floating N-well circuit is employed to remove the body effect at the output PMOS. Moreover, a dynamic driving detector is included to equalize the turn-on voltages for the output PMOS and NMOS transistors. ZigBee is used as a communication channel in this thesis because of its features, including low power, low complexity, medium range, and medium data rate. The 868/915 MHz mode has lower cost and power consumption than those of 2.4 GHz mode, and the data rate is far enough for WBAN applications. Moreover, lower carrier frequency causes less unnecessary power absorbed by human tissue. Therefore, the ZigBee tranceiver with 868/915 MHz mode is explored. A low power all digital phase lock loop (ADPLL) using a controller which employs a binary frequency searching method is also proposed as a clock generator of PG. Glitch hazards and timing violations which occurred very often in prior ADPLLs are avoided by a novel control method and a new digital-controlled oscillator (DCO) with multiplexers. Besides, the feedback DCO is disabled half a cycle in every two cycles so as to reduce 25% of dynamic power theoretically.

<p><!--st1\:*{behavior:url(#ieooui) } --><!--[endif]--> <!-- /* Font Definitions */ @font-face {font-family:Garamond; panose-1:2 2 4 4 3 3 1 1 8 3; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:647 0 0 0 159 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; mso-layout-grid-align:none; punctuation-wrap:simple; text-autospace:none; font-size:12.0pt; mso-bidi-font-size:10.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-GB; mso-fareast-language:EN-US;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 70.85pt 70.85pt 70.85pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --></p><p>To implement a utility wireless sensor network, investigation of different wireless protocols has been performed. The protocols are Bluetooth, Wi-Fi, IEEE 802.15.4 and Zigbee. Consecutively literature studies have made it comprehensible to understand the function of the protocols that are suitable for development of wireless sensor networks. The importance of low cost, low power, reliable and high-quality properties for long distances are significant. IEEE 802.15.4 and Zigbee protocol are proper to implement as a wireless sensor network.</p><p> </p><p>To reduce the human efforts in the configuration of the system, a comfortable method is implemented to facilitate the procedure. The applied method is based on an automatic configuration of the system. The configuration and the decision taking are implemented in the software. The system is designed to avoid interference to other wireless networks with the possibilities of reconfiguration.</p><p>A uniform hardware and software design with separate functions of the system decided by a subsequent command for configuration is preferable. This imposes an advantage that increases the flexible potential of the system when a uniform solution is implemented.</p><p> </p><p>To support the basic communication principles and control of the system, a buffer implementation has been introduced. The functionality of decision taking is distributed, configured by system commands from the host system. Detecting of system commands requires a properly operating buffer management. In consideration to the power consumption in reference to battery utilizations, the settings of RF-module and microcontroller have a powerful impact to reduce the power consumption. All possibilities of hibernates and avoidance of unnecessarily transmitting, should be deactivated to minimize the power consumption.</p><p> </p>

<p>The wish to measure different environmental parameters, in for example office buildings, is getting more and more important in today’s society. Since the sensors should be easily deployed they need to be battery powered and communicate wireless. Furthermore the radio range must be extended because of the limited range on the free frequencies. This is where wireless sensor networks come in and extend the range by relaying the data through other nodes in the network, thereby extending the total range of the network.</p><p>The purpose of this thesis work is to develop a protocol for such a wireless sensor network, capable of delivering and relaying sensor data through the nodes of the network.</p><p>The protocol has been implemented in hardware also designed in this thesis. Tests of the network have been performed and the results have shown that the network works very well and fulfills all of the requirements. Furthermore the power consumption is only 15% of the required value. This thesis has produced a very good platform to use as a base for further development of a commercial product.</p>

ITC/USA 2014 Conference Proceedings / The Fiftieth Annual International Telemetering Conference and Technical Exhibition / October 20-23, 2014 / Town and Country Resort & Convention Center, San Diego, CA / The wireless acquisition system LISA has been designed for mechanical phenomenon analysis onboard aircrafts. It has been in use for more than one year now. This paper describes the organization of this equipment and the experiences related by first users.

A decade ago, wireless technology was unimaginable in its application in industrial automation as wireless had poor reliability and security in the form of time delays and frame losses. Also, lack of interoperability and standards has been a barrier for wireless applications in control system. But with recent advancements in wireless technology, and with the underlying advantages of wireless like low infrastructural costs, scalability, mobility, and ability to operate in extreme and remote environments, many are seriously considering wireless for industrial automation solutions. For wireless implementation in industries, it is important to understand its characteristics - security, update rates, data types, protocols, and latency time. Protocol being an important characteristic of any communication, is to be chosen intelligently for maximum efficiency. Because of the complexity of creating a communication protocol, existing information technology (IT) protocols such as Wi-Fi, Bluetooth, and ZigBee were used in industries. But as applications widened, and interoperability became an important factor to be considered, it was required to standardize the protocols used. ISA SP100 and WirelessHART are results of this standardizing process. For the last few years, there has been a huge discussion on which of these protocols are robust and work better, and none has emerged as clear winners. The aim of this thesis is to explore the capabilities and limitations of each of these protocols for various industrial applications. This thesis considers all these protocols and helps choose the best fit for industrial applications and includes study of security, reliability, and efficiency of these protocols. / text

Η ασύρματη μετάδοση δεδομένων τηλεϊατρικής καθιστά ένα εύρος μετρήσεων που θα έπρεπε να έχουν καθηλωμένο τον ασθενή, να γίνεται εύκολα και απομακρυσμένα. Στην παρούσα εργασία γίνεται διερεύνηση των δυνατοτήτων που προσφέρει η ασύρματη μετάδοση τηλεϊατρικών δεδομένων και ειδικότερα το πρωτόκολλο IEEE 802.15.4, το οποίο εντάσσεται στα ασύρματα δίκτυα χαμηλής ισχύος. Το πρωτόκολλο αυτό υποστηρίζει χαμηλό ρυθμό μετάδοσης δεδομένων, ικανό όμως για τη μετάδοση βιολογικών δεδομένων, έχει χαμηλή κατανάλωση ισχύος, είναι χαμηλού κόστους και έχει μια εμβέλεια 10 έως 75 μέτρα. Παράλληλα με τη διερεύνηση των δυνατοτήτων του συγκεκριμένου πρωτοκόλλου στην μετάδοση βιολογικών δεδομένων γίνεται και υλοποίηση σε hardware ενός συστήματος συγκέντρωσης και μετάδοσης των δεδομένων με το πρωτόκολλο IEEE 802.15.4. / The wireless data transmission in telemedicine makes a range of measurements that should have riveted the patient, easily and remotely. In the present work is exploring the possibilities to offer wireless telemedical data transmission and in particular Protocol IEEE 802.15.4, Zigbee. This protocol supports low data transmission rates, but able to transmit biological data. Alongside exploring the possibilities of the transmission protocol to biological data and is a hardware implementation of a system gathering and data transmission protocol with IEEE 802.15.4.

Wireless sensor networks are the collection of wireless nodes that are deployed to monitor certain phenomena of interest. Once the node takes measurements it transmits to a base station over a wireless channel. The base station collects data from all the nodes and do further analysis. To save energy, it is often useful to build clusters, and the head of each cluster communicates with the base station. Initially, we do the simulation analysis of the Zigbee networks where few nodes are more powerful than the other nodes. The results show that in the mobile heterogeneous sensor networks, due to phenomenon orphaning and high cost of route discovery and maintenance, the performance of the network degrades with respect to the homogeneous network. The core of this thesis is to empirically analyze the sensor network. Due to its resource constraints, low power wireless sensor networks face several technical challenges. Many protocols work well on simulators but do not act as we expect in the actual deployments. For example, sensors physically placed at the top of the heap experience Free Space propagation model, while the sensors which are at the bottom of the heap have sharp fading channel characteristics. In this thesis, we show that impact of asymmetric links in the wireless sensor network topology and that link quality between sensors varies consistently. We propose two ways to improve the performance of Link Quality Indicator (LQI) based algorithms in the real asymmetric link sensor networks. In the first way, network has no choice but to have some sensors which can transmit over the larger distance and become cluster heads. The number of cluster heads can be given by Matérn Hard-Core process. In the second solution, we propose HybridLQI which improves the performance of LQI based algorithm without adding any overhead on the network. Later, we apply theoretical clustering approaches in sensor network to real world. We deploy Matérn Hard Core Process and Max-Min cluster Formation heuristic on real Tmote nodes in sparse as well as highly dense networks. Empirical results show clustering process based on Matérn Hard Core Process outperforms Max-Min Cluster formation in terms of the memory requirement, ease of implementation and number of messages needed for clustering. Finally, using Absorbing Markov chain and measurements we study the performance of load balancing techniques in real sensor networks.

Condition monitoring of machines and structures is commonly utilized in order to prevent failures before they can occur. For these reasons, data such as temperature, vibrations or displacements are collected and analysed. Sensors collect this information, which is sent to a base station to be examined. Wired sensors have been used since the appearance of condition monitoring maintenance; however, wireless sensors are becoming more popular in this area. The use of wired sensors can be very expensive, due to the cost related to the installation and maintenance of the wiring between the sensors and the base station. In wind turbines, wired sensor networks are starting to be substituted by wireless sensor networks. However, for tidal turbines, such as those developed by Delta Stream, this is still a challenge. The use of batteries to supply energy to sensors is not an optimal solution for turbines that are located in remote areas. Batteries have a limited life and their replacement is costly and complicated. Thus, alternative sources of energy have to be found. The environment found in a tidal turbine provides several sources of profitable energy, such as vibration and temperature differences which can be used to supply energy by means of energy harvesters. The aim of this project is to demonstrate the operation of self-powered short-range wireless sensor nodes for a potential use in a Delta Stream nacelle of tidal turbine. This project focuses on the wireless communication inside the nacelle (where most of the sensors are located) using a land protocol (Zigbee), and the energy harvesting using waste heat by means of thermoelectric devices. In order to prove the operation of the whole system (thermoelectric generator and sensor node), a power management circuit was also constructed and tested.