199 research outputs found
Target Detection Architecture for Resource Constrained Wireless Sensor Networks within Internet of Things
Wireless sensor networks (WSN) within Internet of Things (IoT) have the potential
to address the growing detection and classi�cation requirements among many
surveillance applications. RF sensing techniques are the next generation technologies
which o�er distinct advantages over traditional passive means of sensing
such as acoustic and seismic which are used for surveillance and target detection
applications of WSN. RF sensing based WSN within IoT detect the presence of
designated targets by transmitting RF signals into the sensing environment and
observing the re
ected echoes. In this thesis, an RF sensing based target detection
architecture for surveillance applications of WSN has been proposed to detect the
presence of stationary targets within the sensing environment.
With multiple sensing nodes operating simultaneously within the sensing region,
diversity among the sensing nodes in the choice of transmit waveforms is required.
Existing multiple access techniques to accommodate multiple sensing nodes within
the sensing environment are not suitable for RF sensing based WSN. In this thesis,
a diversity in the choice of the transmit waveforms has been proposed and transmit
waveforms which are suitable for RF sensing based WSN have been discussed. A
criterion have been de�ned to quantify the ease of detecting the signal and energy
e�ciency of the signal based on which ease of detection index and energy e�ciency
index respectively have been generated. The waveform selection criterion proposed
in this thesis takes the WSN sensing conditions into account and identi�es the
optimum transmit waveform within the available choices of transmit waveforms
based on their respective ease of detection and energy e�ciency indexes.
A target detector analyses the received RF signals to make a decision regarding
the existence or absence of targets within the sensing region. Existing target detectors
which are discussed in the context of WSN do not take the factors such
as interference and nature of the sensing environment into account. Depending
on the nature of the sensing environment, in this thesis the sensing environments are classi�ed as homogeneous and heterogeneous sensing environments. Within
homogeneous sensing environments the presence of interference from the neighbouring
sensing nodes is assumed. A target detector has been proposed for WSN
within homogeneous sensing environments which can reliably detect the presence
of targets. Within heterogeneous sensing environments the presence of clutter and
interfering waveforms is assumed. A target detector has been proposed for WSN
within heterogeneous sensing environments to detect targets in the presence of
clutter and interfering waveforms. A clutter estimation technique has been proposed
to assist the proposed target detector to achieve increased target detection
reliability in the presence of clutter. A combination of compressive and two-step
target detection architectures has been proposed to reduce the transmission costs.
Finally, a 2-stage target detection architecture has been proposed to reduce the
computational complexity of the proposed target detection architecture
Chipless RFID sensor systems for structural health monitoring
Ph. D. ThesisDefects in metallic structures such as crack and corrosion are major sources of catastrophic
failures, and thus monitoring them is a crucial issue. As periodic inspection using the nondestructive testing and evaluation (NDT&E) techniques is slow, costly, limited in range, and
cumbersome, novel methods for in-situ structural health monitoring (SHM) are required.
Chipless radio frequency identification (RFID) is an emerging and attractive technology to
implement the internet of things (IoT) based SHM. Chipless RFID sensors are not only wireless,
passive, and low-cost as the chipped RFID counterpart, but also printable, durable, and allow
for multi-parameter sensing.
This thesis proposes the design and development of chipless RFID sensor systems for SHM,
particularly for defect detection and characterization in metallic structures. Through simulation
studies and experimental validations, novel metal-mountable chipless RFID sensors are
demonstrated with different reader configurations and methods for feature extraction, selection,
and fusion. The first contribution of this thesis is the design of a chipless RFID sensor for crack
detection and characterization based on the circular microstrip patch antenna (CMPA). The
sensor provides a 4-bit ID and a capability of indicating crack width and orientation
simultaneously using the resonance frequency shift. The second contribution is a chipless RFID
sensor designed based on the frequency selective surface (FSS) and feature fusion for corrosion
characterization. The FSS-based sensor generates multiple resonance frequency features that
can reveal corrosion progression, while feature fusion is applied to enhance the sensitivity and
reliability of the sensor. The third contribution deals with robust detection and characterization
of crack and corrosion in a realistic environment using a portable reader. A multi-resonance
chipless RFID sensor is proposed along with the implementation of a portable reader using an
ultra-wideband (UWB) radar module. Feature extraction and selection using principal
component analysis (PCA) is employed for multi-parameter evaluation.
Overall, chipless RFID sensors are small, low-profile, and can be used to quantify and
characterize surface crack and corrosion undercoating. Furthermore, the multi-resonance
characteristics of chipless RFID sensors are useful for integrating ID encoding and sensing
functionalities, enhancing the sensor performance, as well as for performing multi-parameter
analysis of defects. The demonstrated system using a portable reader shows the capability of
defects characterization from a 15-cm distance. Hence, chipless RFID sensor systems have
great potential to be an alternative sensing method for in-situ SHM.Indonesia Endowment Fund for Education
(LPDP
A Hybrid Indoor Location Positioning System
Indoor location positioning techniques have experienced impressive growth in recent years. A wide range of indoor positioning algorithms has been developed for various applications. In this work a practical indoor location positioning technique is presented which utilizes off-the-shelf smartphones and low-cost Bluetooth Low Energy (BLE) nodes without any further infrastructure. The method includes coarse and fine modes of location positioning. In the coarse mode, the received signal strength (RSS) of the BLE nodes is used for location estimation while in the fine acoustic signals are utilized for accurate positioning. The system can achieve centimeter-level positioning accuracy in its fine mode. To enhance the system’s performance in noisy environments, two digital signal processing (DSP) algorithms of (a) band-pass filtering with audio pattern recognition and (b) linear frequency modulated chirp signal with matched filter are implemented. To increase the system’s robustness in dense multipath environments, a method using data clustering with sliding window is employed. The received signal strength of BLE nodes is used as an auxiliary positioning method to identify the non-line-of-sight (NLoS) propagation paths in the acoustic positioning mode. Experimental measurement results in an indoor area of 10 m2 indicate that the positioning error falls below 6 cm
Sensors and Systems for Indoor Positioning
This reprint is a reprint of the articles that appeared in Sensors' (MDPI) Special Issue on “Sensors and Systems for Indoor Positioning". The published original contributions focused on systems and technologies to enable indoor applications
Millimeter-scale RF Integrated Circuits and Antennas for Energy-efficient Wireless Sensor Nodes
Recently there has been increased demand for a millimeter-scale wireless sensor node for applications such as biomedical devices, defense, and surveillance. This form-factor is driven by a desire to be vanishingly small, injectable through a needle, or implantable through a minimally-invasive surgical procedure. Wireless communication is a necessity, but there are several challenges at the millimeter-scale wireless sensor node. One of the main challenges is external components like crystal reference and antenna become the bottleneck of realizing the mm-scale wireless sensor node device. A second challenge is power consumption of the electronics. At mm-scale, the micro-battery has limited capacity and small peak current. Moreover, the RF front-end circuits that operates at the highest frequency in the system will consume most of the power from the battery. Finally, as node volume reduces, there is a challenge of integrating the entire system together, in particular for the RF performance, because all components, including the battery and ICs, need to be placed in close proximity of the antenna.
This research explores ways to implement low-power integrated circuits in an energy-constrained and volume constrained application. Three different prototypes are mainly conducted in the proposal. The first is a fully-encapsulated, autonomous, complete wireless sensor node with UWB transmitter in 10.6mm3 volume. It is the first time to demonstrate a full and stand-alone wireless sensing functionality with such a tiny integrated system. The second prototype is a low power GPS front-end receiver that supports burst-mode. A double super-heterodyne topology enables the reception of the three public GPS bands, L1, L2 and L5 simultaneously. The third prototype is an integrated rectangular slot loop antenna in a standard 0.13-μm BiCMOS technology. The antenna is efficiently designed to cover the bandwidth at 60 GHz band and easily satisfy the metal density rules and can be integrated with other circuitry in a standard process.PHDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/143972/1/hskims_1.pd
Super compact UWB monopole antenna for small IoT devices
This article introduces a novel, ultrawideband (UWB) planar monopole antenna printed on Roger RT/5880 substrate in a compact size for small Internet of Things (IoT) applications. The total electrical dimensions of the proposed compact UWB antenna are 0.19 λo × 0.215 λo × 0.0196 λo with the overall physical sizes of 15 mm × 17 mm × 1.548 mm at the lower resonance frequency of 3.8 GHz. The planar monopole antenna is fed through the linearly tapered microstrip line on a partially structured ground plane to achieve optimum impedance matching for UWB operation. The proposed compact UWB antenna has an operation bandwidth of 9.53 GHz from 3.026 GHz up to 12.556 GHz at -10 dB return loss with a fractional bandwidth (FBW) of about 122%. The numerically computed and experimentally measured results agree well in between. A detailed time-domain analysis is additionally accomplished to verify the radiation efficiency of the proposed antenna design for the ultra-wideband signal propagation. The fabricated prototype of a compact UWB antenna exhibits an omnidirectional radiation pattern with the low peak measured gain required of 2.55 dBi at 10 GHz and promising radiation efficiency of 90%. The proposed compact planar antenna has technical potential to be utilized in UWB and IoT applications
Intelligent Circuits and Systems
ICICS-2020 is the third conference initiated by the School of Electronics and Electrical Engineering at Lovely Professional University that explored recent innovations of researchers working for the development of smart and green technologies in the fields of Energy, Electronics, Communications, Computers, and Control. ICICS provides innovators to identify new opportunities for the social and economic benefits of society.  This conference bridges the gap between academics and R&D institutions, social visionaries, and experts from all strata of society to present their ongoing research activities and foster research relations between them. It provides opportunities for the exchange of new ideas, applications, and experiences in the field of smart technologies and finding global partners for future collaboration. The ICICS-2020 was conducted in two broad categories, Intelligent Circuits & Intelligent Systems and Emerging Technologies in Electrical Engineering
Characterization of 28 nm FDSOI MOS and application to the design of a low-power 2.4 GHz LNA
IoT is expected to connect billions of devices all over world in the next years, and in a near future, it is expected to use LR-WPAN in a wide variety of applications. Not all the devices will require of high performance but will require of low power hungry systems since most of them will be powered with a battery. Conventional CMOS technologies cannot cover these needs even scaling it to very small regimes, which appear other problems. Hence, new technologies are emerging to cover the needs of this devices. One promising technology is the UTBB FDSOI, which achieves good performance with very good energy efficiency. This project characterizes this technology to obtain a set of parameters of interest for analog/RF design. Finally, with the help of a low-power design methodology (gm/Id approach), a design of an ULP ULV LNA is performed to check the suitability of this technology for IoT
Smart Monitoring and Control in the Future Internet of Things
The Internet of Things (IoT) and related technologies have the promise of realizing pervasive and smart applications which, in turn, have the potential of improving the quality of life of people living in a connected world. According to the IoT vision, all things can cooperate amongst themselves and be managed from anywhere via the Internet, allowing tight integration between the physical and cyber worlds and thus improving efficiency, promoting usability, and opening up new application opportunities. Nowadays, IoT technologies have successfully been exploited in several domains, providing both social and economic benefits. The realization of the full potential of the next generation of the Internet of Things still needs further research efforts concerning, for instance, the identification of new architectures, methodologies, and infrastructures dealing with distributed and decentralized IoT systems; the integration of IoT with cognitive and social capabilities; the enhancement of the sensing–analysis–control cycle; the integration of consciousness and awareness in IoT environments; and the design of new algorithms and techniques for managing IoT big data. This Special Issue is devoted to advancements in technologies, methodologies, and applications for IoT, together with emerging standards and research topics which would lead to realization of the future Internet of Things
Ultra-low power IoT applications: from transducers to wireless protocols
This dissertation aims to explore Internet of Things (IoT) sensor nodes in various application scenarios with different design requirements. The research provides a comprehensive exploration of all the IoT layers composing an advanced device, from transducers to on-board processing, through low power hardware schemes and wireless protocols for wide area networks.
Nowadays, spreading and massive utilization of wireless sensor nodes pushes research and industries to overcome the main limitations of such constrained devices, aiming to make them easily deployable at a lower cost. Significant challenges involve the battery lifetime that directly affects the device operativity and the wireless communication bandwidth. Factors that commonly contrast the system scalability and the energy per bit, as well as the maximum coverage.
This thesis aims to serve as a reference and guideline document for future IoT projects, where results are structured following a conventional development pipeline. They usually consider communication standards and sensing as project requirements and low power operation as a necessity.
A detailed overview of five leading IoT wireless protocols, together with custom solutions to overcome the throughput limitations and decrease the power consumption, are some of the topic discussed. Low power hardware engineering in multiple applications is also introduced, especially focusing on improving the trade-off between energy, functionality, and on-board processing capabilities. To enhance these features and to provide a bottom-top overview of an IoT sensor node, an innovative and low-cost transducer for structural health monitoring is presented. Lastly, the high-performance computing at the extreme edge of the IoT framework is addressed, with special attention to image processing algorithms running on state of the art RISC-V architecture. As a specific deployment scenario, an OpenCV-based stack, together with a convolutional neural network, is assessed on the octa-core PULP SoC
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