This paper presents the design and implementation of a web-based wireless indoor climate control system. The user interface of the system is implemented as a web service. People can login to the website and remotely control the indoor climate of different locations. A wireless sensor network is deployed in each location to execute control commands. A gateway is implemented to synchronize the information between the wireless sensor network and the web service. The gateway software also includes scheduling function and different control algorithms to improve the control result. Additionally, the system security and availability are highly considered in this system. The gateway software implements a warning function which sends warning messages when emergency happens. Finally, the whole wireless control system architecture is modularly designed. It is easy to add different control applications or different control algorithms into the system.

As defined by the ZigBee standard, a router should be mains-powered in order to maintain the mesh feature of the ZigBee network. This study presents a method which allows the ZigBee router goes into sleep mode periodically and keeps the same mesh feature during the ZigBee communications. In this study, the standard ZigBee communication is separated into two synchronized clusters. The first cluster includes the communication between end devices and the associated router. The sensor message report time of different end devices are scheduled by the router in different collision-free time slots within a predefined time interval. The second cluster includes the mesh communication between routers and the concentrator. All routers are synchronized so that they wake up at the same time to maintain the mesh feature. In order to maximize the router battery lifetime, algorithms are developed so that the concentrator communicates with routers according to the network routing records. Additionally, in order to recover the broken communication, special logics are implemented in routers and end device so that they can rejoin the wireless sensor network with low power consumption. Finally, a battery lifetime model is presented which can be utilized to calculate battery lifetime of the ZigBee router under different network configurations.

This paper presents the methods for the ZigBee network reliability enhancement and the battery life time optimization. The paper begins with the introduction of the common communication problems due to the broken links between sensor module and message relay, or between different relays. Extra message hand shake mechanisms are added to solve different problem mentioned at the beginning. Finally, a general purpose reliability enhancement component is developed as a state machine which can be work together with ZigBee protocol to enhance ZigBee network communication reliability. Moreover, the battery life time of the sensor module during link broken is considerably increased after the enhancement.

This paper presents a component based wireless monitoring and control system. The system is introduced from both the system architecture and function point of view. The paper begins with the introduction of the component design and the communication interaction between them. The system is composed by three components, the wireless sensor network, the local server and the main server. Wireless sensor networks are deployed in different locations for remote monitoring and control purpose. The monitoring results and control commands are synchronized between the main server and wireless sensor networks via local servers. The test results of the battery life time calculation and remote monitoring field test results are presented in the end of the paper.

A wireless solution of remote climate control for cultural buildings is presented in this paper. The system allows users to use web service to control climate in different cultural buildings, like churches. The wireless sensor networks deployed in churches receive the control commands and manage the indoor climate. The whole system is modularly designed, which makes possible an easy service extension, system reconfiguration and modification. This paper includes the system overview and the software design of each part within the system.

This book is based on recent research work conducted by the authors dealing with the design and development of active and passive microwave components, integrated circuits and systems. It is divided into seven parts. In the first part comprising the first two chapters, alternative concepts and equations for multiport network analysis and characterization are provided. A thru-only de-embedding technique for accurate on-wafer characterization is introduced. The second part of the book corresponds to the analysis and design of ultra-wideband low- noise amplifiers (LNA).

Ultra wideband technology is one of the most promising directions in the rapidly developing modern communications. Ultra wideband communication system applications include radars, wireless personal area networks, sensor networks, imaging systems and high precision positioning systems. Ultra wideband transmission is characterized by high data rate, availability of low-cost transceivers, low transmit power and low interference. The proposed book consisting of 19 chapters presents both the state-of-the-art and the latest achievements in ultra wideband communication system performance, design and components. The book is addressed to engineers and researchers who are interested in the wide range of topics related to ultra wideband communications.

Methods to improve the reliability and optimize the system latency of our own-developed ZigBee remote sensing system are introduced in this paper. The concept of this system utilizes the ZigBee network to transmit sensor information and process them at both local and remote databases. The enhancement has been done in different parts in this system. In the ZigBee network part, the network topology is configured and controlled. The latency for message transmitting is also optimized. In the data processing part, the network status check function and data buffer function are introduced to improve the system reliability. Additionally, the system latency is measured to compare with the Ad-hoc On Demand Distance Vector algorithm used in the ZigBee standard.

A wireless remote sensing system using the ZigBee standard ispresented in this paper. This system is a wireless solution formonitoring purpose in cultural buildings in order to protectcultural heritage. The concept of this system utilizes ZigBeenetworks to carry and transmit data collected by sensors andstore them into both local and remote databases. Thus, users canmonitor the measured data locally or remotely. Especially, thepower consumption is optimized to extend the lifetime of thebattery-driven devices. Moreover, since the system has amodular architecture, it is easy to add extra services into thissystem.

The topic of this dissertation is divided into two parts where the first part presents high-speed data transmission on flexible cables and the second part presents a wireless remote monitoring and controlling system with wireless data transmission.

The demand on high-speed data communications has pushed both the wired and wireless technologies to operate at higher and higher frequencies. Classic Kirchhoff’s voltage and current laws cannot be directly applied, when entering the microwave spectrum for frequency above 1 GHz. Instead, the transmission line theory should be used. Most of the wired communication products use bit-serial cables to connect devices. To transfer massive data at high speed, parallel data transfer techniques can be utilized and the speed can be increased by the number of parallel lines or cables, if the transfer rate per line or cable can be maintained. However, the lines or cables must be well-shielded so the crosstalk between them can be minimized.

Differential lines can also be used to increase the data speed further compared to the single-ended lines, along with saving the power consumption and reducing the electromagnetic interference. However, characterization for differential lines is not as straight forward as for single-ended cases using standard S-parameters. Instead, mixed-mode S-parameters are needed to describe the differential-, common- and mixed-mode characteristics of the differential signal. Mixed-mode S-parameters were first introduced in 1995 and are now widely used. However, improvements of the theory can still be found to increase the accuracy of simulations and measurements, which is proposed and presented in this dissertation.

The interest of wireless solution to do remote control and monitoring for cultural building has been increasing. Available solutions on the market are mostly wired and very expensive. The available wireless solutions often offer limited network size with point-to-point radio link. Furthermore, the wired solution requires operation on the building, which is not the preferred way since it will damage the historical values of cultural heritage buildings. Wireless solutions on the other hand can offer flexibility when deploying the network, i.e., operation on the building can be avoided or kept to the minimum.

A platform for wireless remote monitoring and control has been established for various deployments at different cultural buildings. The platform has a modular design to ease future improvement and expansion of the system. The platform is based on the ZigBee standard, which is an open standard, specified with wireless sensor network as focus. Three different modules have been developed. The performance has been studied and optimized. The network has been deployed at five different locations in Sweden for data collection and verification of the system stability.

The remote monitoring and control functions of the developed platform have received a nomination for the Swedish Embedded Award 2010 and been demonstrated at the Scandinavia Embedded Conference 2010 in Stockholm.Communication