Communication Subsystems for Emerging Wireless Technologies

The paper describes a multi-disciplinary design of modern communication systems. The design starts with the analysis of a system in order to define requirements on its individual components. The design exploits proper models of communication channels to adapt the systems to expected transmission conditions. Input filtering of signals both in the frequency domain and in the spatial domain is ensured by a properly designed antenna. Further signal processing (amplification and further filtering) is done by electronics circuits. Finally, signal processing techniques are applied to yield information about current properties of frequency spectrum and to distribute the transmission over free subcarrier channels

Tunable Sub-Nanosecond Ultra Wideband Narrow Pulse Generator For Microwave Imaging

In recent years, the Ultra Wideband (UWB) technology-based systems exhibited higher performance metrics over narrow band communication systems. The UWB microwave imaging is an emerging application in the biomedical, object detection, and ranging fields. The Narrowband Pulse Generator (NPG) is an essential element of any UWB imaging system and its characteristics partially determine the overall performance of the system. Numerous NPG designs have been developed for specific types of applications and most of them designed for CMOS technology integration. Additionally, they lack the flexibility of user pulse width tuning. In this research, the main contribution is the design of a low-cost sub-nanosecond NPG with many features like tunable pulse duration and to generate a pulse shape with ultrafast rise and fall times that could enhance the quality of UWB microwave images. The design aims to reduce the NPG cost with the use of off-the-shelf components. The very low pulse transition times led to higher BW values in the frequency spectrum and would presage to enhance the quality of images been reconstructed from UWB radar imaging systems. The shortest pulse provided by the proposed NPG is about 820 ps with a fall time of about 64 ps and a pulse level of 200 mV (single-ended). The aforementioned pulse data has been simulated in a locally developed image reconstruction algorithm (EDAS) to detect hypothetical objects and the resultant images show significant quality enhancement in comparison to a Gaussian pulse (or its derivative) with an equivalent duration. Image entropy values have been reduced from 248 to 51. This simulation validated the concept of trapezoidal pulse (or its derivative) influence on image resolution. For a further validation, an experimental UWB imaging system has been configured with a circular array of antennas to detect and locate different targets made of selected materials. The proposed NPG pulses have been applied, after amplification, to the above system. The reconstructed images compared to those obtained from other pulse sources like the VNA and PPG. The images generated from the proposed NPG show better quality in most cases. Compared to VNA images, image entropy values dropped from 63.66 to 43.23 for clay rod, and from 143.77 to 46.50 for an Aluminum rod. The promising results of the proposed NPG can hopefully be applied as a useful tool to obtain higher resolution images and better target detection accuracy in many industrial applications

Implementation Aspects of a Transmitted-Reference UWB Receiver

In this paper, we discuss the design issues of an ultra wide band (UWB) receiver targeting a single-chip CMOS implementation for low data-rate applications like ad hoc wireless sensor networks. A non-coherent transmitted reference (TR) receiver is chosen because of its small complexity compared to other architectures. After a brief recapitulation of the UWB fundamentals and a short discussion on the major differences between coherent and non-coherent receivers, we discuss issues, challenges and possible design solutions. Several simulation results obtained by means of a behavioral model are presented, together with an analysis of the trade-off between performance and complexity in an integrated circuit implementation

Manufacturing Logistics and Packaging Management Using RFID

none2The chapter is centred on the analysis of internal flow traceability of goods (products and/or packaging) along the supply chain by an Indoor Positioning System (IPS) based on Radio Frequency IDentification (RFID) technology. A typical supply chain is an end-to-end process with the main purpose of production, transportation, and distribution of products. It is relative to the products’ movements from the supplier to the manufacturer, distributor, retailer and finally to the end consumer. Moreover, a supply chain is a complex amalgam of parties that require coordination, collaboration, and information exchange among them to increase productivity and efficiency [1, 2]. A supply chain is made up of people, activities, and resources involved in moving products from suppliers to customers and information from customers to suppliers. For this reason, the traceability of logistics flows (physical and information) is a very important issue for the definition and design of manufacturing processes, improvement of layout and increase of security in work areas. European Parliament (Regulation (EC) No. 178/2002) [3] makes it compulsory to trace goods and record all steps, used materials, manufacturing processes, etc. during the entire life cycle of a product [4]. According to the European Parliament, companies recognize the need and importance of tracing materials in indoor environments. Traditionally, the traceability system is performed through the asynchronous fulfilment of checkpoints (i.e. doorways) by materials. In such cases, the tracking is manual, executed by operators. Often companies are not aware of the inefficiencies due to these systems of traceability such as low precision and accuracy in measurements (i.e. no information between doorways), more time spent by operators and costs (due to the full-effort of operators who have to trace target positions and movements). According to [5] every day millions of transport units (cases, boxes, pallets, and containers) are managed worldwide with limited or even with lack of knowledge regarding their status in real-time. In order to overcome the lack of data due to traceability, automatic identification procedures (Auto-ID) could be a solution. They have become very popular in many service industries, purchasing and distribution logistics, manufacturing companies and material flow systems. Automatic identification procedures provide information about people, vehicles, goods, and products in transit within the company [6]. It is possible to note several advantages using an automatic identification system such as the reduction of theft, increase of security during the transport and distribution of assets, and increase of knowledge of objects’ position in real-time. Automatic identification procedures can also be applied to packaging products, instead of to each item contained in the package. Packaging is becoming the cornerstone of processing activities [7]. Sometimes products are very expensive and packages contain important and critical goods (for example dangerous or explosive materials) and the tracking of goods – and packaging in particular – is a critical function. The main advantage of automatic system application to packages is the possibility to map the path of all items contained into the packages and to find out their real-time position. The installation of automatic systems in packages allows costs and time to be reduced (by installing, for example, the tag directly on the package instead of on each product contained inside the package). The purpose of the chapter is to provide an innovative automatic solution for the traceability of everything that moves within a company, in order to simplify and improve the process of logistics flow traceability and logistics optimization. The chapter deals with experimental research that consists of several tests, static and dynamic, tracing the position (static) and movements (dynamic) of targets (e.g. people, vehicles, objects) in indoor environments. In order to identify the best system to use in the real-time traceability of products, the authors have chosen Real Time Location Systems (RTLSs) and, in particular, the Indoor Positioning Systems (IPSs) based on Radio Frequency IDentification (RFID) technology. The authors discuss the RFID based system using UWB technology, both in terms of design of the system and real applications. The chapter is organized as follows: Section 2 briefly describes IPS systems, looking in more depth at RFID technology. After that the experimental research with the relative results and discussion are described in Section 3. Section 4 presents an analysis of RFID traceability systems applied to packaging. Conclusions and further research are discussed in Section 5.mixedREGATTIERI A.; SANTARELLI GREGATTIERI A.; SANTARELLI

Impulse radio ultra wideband over fiber techniques for broadband in-building network applications

In recent years, the demand for high bandwidth and mobility from the end users has been continuously growing. To satisfy this demand, broadband communication technologies that combined the benefit of both wired and wireless are considered as vital solutions. These hybrid optical wireless solutions enable multi-Gbit/s transmission as well as adequate flexibility in terms of mobility. Optical fiber is the ideal medium for such hybrid solution due its signal transparency and wide bandwidth. On the other hand, ultra wideband(UWB) radio over optical fiber technology is considered to be one of the key promising technologies for broadband communication and sensor network applications. The growing interest for UWB is mainly due to its numerous attractive features, such as low power spectral density, tolerance to multipath fading, low probability of interception, coexistence with other wireless services and capability of providing cost-effective > 1 Gb/s transmission. The main idea of UWB over fiber is to deliver UWB radio signals over optical channels, where the optical part serves as a backbone communication infrastructure to carry the UWB signal with a bandwidth of several GHz. This enables multiple novel applications such as: range extension of high speed wireless personal area networks (WPANs), low cost distributed antenna systems, secure and intelligent networks, or delivering broadband services to remote areas. In particular, this thesis deals with novel concepts on shaping and generation of IR-UWB pulses, theoretical and experimental demonstrations over different fiber types, routing of integrated wired/wireless IR-UWB services and effect of fiber types on ranging/localization of IR-UWB-over-fiber systems. Accordingly, this thesis investigates techniques for delivery of high data rate wireless services using impulse radio ultra wideband (IR-UWB) over fiber technology for both access and in-building network applications. To effectively utilize the emission mask imposed for UWB technologies by the Federal Communications Commission(FCC), novel pulse shaping techniques have been investigated and experimentally demonstrated. Comparison of the proposed pulses with conventional ones in terms of the compliance to the FCC-mask requirements, spectral power efficiencies and wireless coverage has been theoretically studied. Simple and efficient optical generation of the new pulse has been experimentally demonstrated. Furthermore, performance evaluation of 2 Gb/s transmission of IR-UWB over different types of fiber such as 25 km silica single-mode, 4.4 km silica multi-mode and 100 m plastic heavily-multi-mode fiber have been performed. To improve the functionalities of in-building networks for the delivery of wireless services; techniques that provide flexibility in terms of dynamic capacity allocation have been investigated. By employing wavelength conversion based on cross-gain modulation in optical semiconductor amplifiers(SOA), routing of three optical channels of IR-UWB over fiber system has been experimentally realized. To reduce the cost of the overall system and share the optical infrastructure, an integrated testbed for wired baseband data and wireless IR-UWB over 1 km SMF-28 fiber has been developed. Accordingly, 1.25 Gb/s wired baseband and 2 Gb/s wireless IR-UWB data have been successfully transmitted over the testbed. Furthermore, to improve the network flexibility, routing of both wired baseband and wireless signals has been demonstrated. Additionally, the ranging and localization capability of IR-UWB over fiber for in-door wireless picocells have been investigated. The effect of different fiber types (4 km SMF, 4.4 km GI-MMF and 100 m PF GI-POF) on the accuracy of the range estimation using time-of-arrival (ToA) ranging technique has been studied. A high accuracy in terms of cm level was achieved due to the combined effect of high bandwidth IR-UWB pulses, short reach fiber and low chromatic dispersion at 1300nm wavelength. Furthermore, ranging/ localization using IR-UWB over fiber system provides additional benefit of centralizing complex processing algorithms, simplifying radio access points, relaxing synchronization requirement, enabling energy-efficient and efficient traffic management networks. All the concepts, design and system experiments presented in this thesis underline the strong potential of IR-UWB for over optical fiber(silica and plastic) techniques for future smart, capacity and energy-efficient broadband in-building network applications

Hardware Acceleration of Beamforming in a UWB Imaging Unit for Breast Cancer Detection

The Ultrawideband (UWB) imaging technique for breast cancer detection is based on the fact that cancerous cells have different dielectric characteristics than healthy tissues.When a UWB pulse in the microwave range strikes a cancerous region, the reflected signal is more intense than the backscatter originating from the surrounding fat tissue. A UWB imaging system consists of transmitters, receivers, and antennas for the RF part, and of a digital back-end for processing the received signals. In this paper we focus on the imaging unit, which elaborates the acquired data and produces 2D or 3D maps of reflected energies.We show that one of the processing tasks, Beamforming, is the most timing critical and cannot be executed in software by a standard microprocessor in a reasonable time.We thus propose a specialized hardware accelerator for it.We design the accelerator in VHDL and test it in an FPGA-based prototype. We also evaluate its performance when implemented on a CMOS 45nm ASIC technology. The speed-up with respect to a software implementation is on the order of tens to hundreds, depending on the degree of parallelism permitted by the target technology

Radar Technology

In this book “Radar Technology”, the chapters are divided into four main topic areas: Topic area 1: “Radar Systems” consists of chapters which treat whole radar systems, environment and target functional chain. Topic area 2: “Radar Applications” shows various applications of radar systems, including meteorological radars, ground penetrating radars and glaciology. Topic area 3: “Radar Functional Chain and Signal Processing” describes several aspects of the radar signal processing. From parameter extraction, target detection over tracking and classification technologies. Topic area 4: “Radar Subsystems and Components” consists of design technology of radar subsystem components like antenna design or waveform design

A critical analysis of research potential, challenges and future directives in industrial wireless sensor networks

In recent years, Industrial Wireless Sensor Networks (IWSNs) have emerged as an important research theme with applications spanning a wide range of industries including automation, monitoring, process control, feedback systems and automotive. Wide scope of IWSNs applications ranging from small production units, large oil and gas industries to nuclear fission control, enables a fast-paced research in this field. Though IWSNs offer advantages of low cost, flexibility, scalability, self-healing, easy deployment and reformation, yet they pose certain limitations on available potential and introduce challenges on multiple fronts due to their susceptibility to highly complex and uncertain industrial environments. In this paper a detailed discussion on design objectives, challenges and solutions, for IWSNs, are presented. A careful evaluation of industrial systems, deadlines and possible hazards in industrial atmosphere are discussed. The paper also presents a thorough review of the existing standards and industrial protocols and gives a critical evaluation of potential of these standards and protocols along with a detailed discussion on available hardware platforms, specific industrial energy harvesting techniques and their capabilities. The paper lists main service providers for IWSNs solutions and gives insight of future trends and research gaps in the field of IWSNs