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Full-Text Articles in Electrical and Computer Engineering

A Broadband Circularly Polarised Slot Antenna For Ambient Rf Energy Harvesting Applications, Khatereh Nadali, Patrick Mcevoy, Max Ammann Jul 2022

A Broadband Circularly Polarised Slot Antenna For Ambient Rf Energy Harvesting Applications, Khatereh Nadali, Patrick Mcevoy, Max Ammann

Conference papers

Energy harvesting is a potential source of power for integrating compact low-power and self-sustainable wireless devices in ambient backscatter communication systems and IoT networks. In this paper, an electrically small circularly polarised (CP) slot antenna for harvesting is proposed. The measured CP bandwidth for axial ratio values less than 3 dB is 990 MHz (1.7 GHz to 2.69 GHz), while the measured impedance bandwidth is 1,930 MHz (1.45 GHz to 3.38 GHz). The proposed structure can harvest energy from common radio frequency signal emitters operating in GSM 1800/1900, 3G/LTE 2100, 3G/LTE 2300, 4G/LTE 2500, and 2.4GHz Wi-Fi bands, which makes …


A Broadband Cp Elliptical-Slot Antenna For Ambient Rf Energy Harvesting, Khatereh Nadali, Patrick Mcevoy, Max Ammann May 2022

A Broadband Cp Elliptical-Slot Antenna For Ambient Rf Energy Harvesting, Khatereh Nadali, Patrick Mcevoy, Max Ammann

Conference papers

In this paper, a compact broadband CPW-fed circularly polarised elliptical-slot antenna with an inverted- L tuning stub is proposed. The antenna impedance is optimized for broadband operation from 1.62 GHz to 2.97 GHz. The measured CP bandwidth is 934 MHz (1.747-2.681 GHz), that covers common wireless communication bands GSM 1800, GSM 1900, 3G/LTE 2100, 3G/LTE 2300, 4G/LTE 2500, and 2.4GHz Wi-Fi bands. This makes the designed antenna an appropriate candidate for ambient RF energy harvesting purposes.


Wideband Array For Bgan Portable Terminals, Jakub Przepiorowski, Patrick Mcevoy, Max Ammann, Xiulong Bao Jan 2022

Wideband Array For Bgan Portable Terminals, Jakub Przepiorowski, Patrick Mcevoy, Max Ammann, Xiulong Bao

Conference papers

With the increasing demand for global internet connectivity [1], services like INMARSAT’s Broadband Global Area Network (BGAN) are becoming more widely used. BGAN terminals are portable devices that can be plugged into a laptop or a network in a remote location and provide access to the internet via INMARSAT’s I-4 and the emerging I-6 geostationary satellites. BGAN terminals operate in the L-band with the receive band (Rx) of 1518-1559 MHz and the transmit band (Tx) of 1626.5-1675 MHz.


Poster: Acoustic Source Localization Using Straight Line Approximations, Swarnadeep Bagchi, Ruairí De Fréin Jan 2022

Poster: Acoustic Source Localization Using Straight Line Approximations, Swarnadeep Bagchi, Ruairí De Fréin

Conference papers

The short paper extends an acoustic signal delay estimation method to general anechoic scenario using image processing techniques. The technique proposed in this paper localizes acoustic speech sources by creating a matrix of phase versus frequency histograms, where the same phases are stacked in appropriate bins. With larger delays and multiple sources coexisting in the same matrix, it becomes cluttered with activated bins. This results in high intensity spots on the spectrogram, making source discrimination difficult. In this paper, we have employed morphological filtering, chain-coding and straight line approximations to ignore noise and enhance the target signal features. Lastly, Hough …


Dual-Band Dual-Polarized Microstrip Array For Mm-Wave And Sub-6 Ghz Applications, Neeraj Kumar Maurya, Max Ammann, Patrick Mcevoy Jan 2022

Dual-Band Dual-Polarized Microstrip Array For Mm-Wave And Sub-6 Ghz Applications, Neeraj Kumar Maurya, Max Ammann, Patrick Mcevoy

Conference papers

In this paper, a compact dual-band and dual-polarized antenna array with integrated crossover for mm-Wave and sub-6 GHz band Wi-Fi applications is proposed. The proposed dual-band antenna is comprised of a 2x2 array operating at 26 GHz and 5.48 GHz (channel 96). The dual-band crossover consists of a microstrip-grounded CPW-microstrip interface transition. The measured design shows inter and intraband isolation better than 25dB with the crossover on the same plane with a maximum gain of 9.2dBi and 11.83 dBi for 26.25 GHz and 5.48 GHz respectively.


Bayesian Adaptive Path Allocation Techniques For Intra-Datacenter Workloads, Ali Malik, Ruairí De Fréin, Chih-Heng Ke, Hasanen Alyasiri, Obinna Izima Jul 2021

Bayesian Adaptive Path Allocation Techniques For Intra-Datacenter Workloads, Ali Malik, Ruairí De Fréin, Chih-Heng Ke, Hasanen Alyasiri, Obinna Izima

Conference papers

Data center networks (DCNs) are the backbone of many cloud and Internet services. They are vulnerable to link failures, that occur on a daily basis, with a high frequency. Service disruption due to link failure may incur financial losses, compliance breaches and reputation damage. Performance metrics such as packet loss and routing flaps are negatively affected by these failure events. We propose a new Bayesian learning approach towards adaptive path allocation that aims to improve DCN performance by reducing both packet loss and routing flaps ratios. The proposed approach incorporates historical information about link failure and usage probabilities into its …


Grammatical Evolution For Detecting Cyberattacks In Internet Of Things Environments, Hasanen Alyasiri, John Clark, Ali Malik, Ruairí De Fréin Jul 2021

Grammatical Evolution For Detecting Cyberattacks In Internet Of Things Environments, Hasanen Alyasiri, John Clark, Ali Malik, Ruairí De Fréin

Conference papers

The Internet of Things (IoT) is revolutionising nearly every aspect of modern life, playing an ever greater role in both industrial and domestic sectors. The increasing frequency of cyber-incidents is a consequence of the pervasiveness of IoT. Threats are becoming more sophisticated, with attackers using new attacks or modifying existing ones. Security teams must deal with a diverse and complex threat landscape that is constantly evolving. Traditional security solutions cannot protect such sys- tems adequately and so researchers have begun to use Machine Learning algorithms to discover effective defence systems. In this paper, we investigate how one approach from the …


The Effects Of The Transient And Performance Loss Rates On Pv Output Performance, Chibuisi Chinasaokwu Okorieimoh, Brian Norton, Michael Conlon Jun 2021

The Effects Of The Transient And Performance Loss Rates On Pv Output Performance, Chibuisi Chinasaokwu Okorieimoh, Brian Norton, Michael Conlon

Conference papers

Solar photovoltaic (PV) panels experience long-term performance degradation as compared to their initial performance, resulting in lower like-per-like efficiencies and performance ratios. Manufacturers of solar photovoltaic modules normally guarantee a lifespan of more than 20 years. To meet such commitments, it is important to monitor and mitigate PV module degradation during this period, as well as beyond, to recognize maintenance and repair needs. Solar PV modules degrade over time, becoming less effective, less reliable, and eventually unusable. The effects of transient and performance loss rates on the output performance of polycrystalline silicon (p-Si) solar PV modules are the focus of …


Extending Instantaneous De-Mixing Algorithms To Anechoic Mixtures, Swarnadeep Bagchi, Ruairí De Fréin Jun 2021

Extending Instantaneous De-Mixing Algorithms To Anechoic Mixtures, Swarnadeep Bagchi, Ruairí De Fréin

Conference papers

The AdRess algorithm separates sources that are mixed using stereo, pan-mixing in a computationally efficient way. Pan-mixing gives the sources a location in the stereo field by introducing a relative attenuation between the versions of the sources that appear on each channel. AdRess achieves separation by constructing only a frequency-attenuation matrix. We introduce a new algorithm called Delayed-AdRess (D-AdRess), where, in addition to the frequency-attenuation matrix, two other matrices namely, frequency-delay and time-delay are used to separate sources from anechoic mixtures. By anechoic mixtures, we mean mixing scenarios where both attenuation and delays are experienced by the source signals.


Fractal Graphene Patch Antennas And The Thz Communications Revolution, Jonathan Blackledge, A. Boretti, L. Rosa, S. Castelletto Jan 2021

Fractal Graphene Patch Antennas And The Thz Communications Revolution, Jonathan Blackledge, A. Boretti, L. Rosa, S. Castelletto

Conference papers

Fractal antennas have and are continuing to receive attention in regard to the futureof wireless communications. This is because of their wide- and multi-band capabilities, theopportunity of fractal geometries to drive multiple resonances, and, the ability to make smallerand lighter antennas with fewer components and radiative elements with higher gains. Smallscale (i.e. on the micro- and nano-scale) and ultra high frequency (in the Terahertz or THz range)fractal antennas composed of Graphene have the potential to enhance wireless communicationsat a data rate that is unprecedented, i.e.∼1012bits per second. A Fractal Graphene antennais a high-frequency tuneable antenna for radio communications in the …


Power-Weighted Lpc Formant Estimation, Ruairí De Fréin Nov 2020

Power-Weighted Lpc Formant Estimation, Ruairí De Fréin

Conference papers

A power-weighted formant frequency estimation procedure based on Linear Predictive Coding (LPC) is presented. It works by pre-emphasizing the dominant spectral components of an input signal, which allows a subsequent estimation step to extract formant frequencies with greater accuracy. The accuracy of traditional LPC formant estimation is improved by this new power-weighted formant estimator for different classes of synthetic signals and for speech. Power-weighted LPC significantly and reliably outperforms LPC and variants of LPC at the task of formant estimation using the VTR formants dataset, a database consisting of the Vocal Tract Resonance (VTR) frequency trajectories obtained by human experts …


Predicting Quality Of Delivery Metrics For Adaptive Video Codec Sessions, Obinna Izima, Ruairí De Fréin, Mark Davis Nov 2020

Predicting Quality Of Delivery Metrics For Adaptive Video Codec Sessions, Obinna Izima, Ruairí De Fréin, Mark Davis

Conference papers

Predicting video quality will continue to be an active area of research given the dominance of video traffic for years to come. Network service practitioners that are poised to handle the strain on the existing limited bandwidth constraints are better placed to be SLA-compliant. The dynamic and time-varying nature of cloud-hosted services require improved techniques to realize accurate models of the systems. To address this challenge: (1) we propose Codec-aware Network Adaptation Agent (cNAA), an online light-weight data learning engine that achieves accurate and correct predictions of quality of delivery (QoD) metrics, namely jitter for video services. cNAA achieves this …


Long-Term Durability Of Solar Photovoltaic Modules, Chibuisi Chinasaokwu Okorieimoh, Brian Norton Jun 2020

Long-Term Durability Of Solar Photovoltaic Modules, Chibuisi Chinasaokwu Okorieimoh, Brian Norton

Conference papers

Solar photovoltaic (PV) panels experience long-term performance degradation resulting in lower like-per-like efficiencies and performance ratios when compared with their initial performance. Manufacturers of solar photovoltaic modules usually guarantee the life span for more than 20 years. It is therefore necessary to track and mitigate degradation of PV modules over this period to satisfy such guarantees and beyond this period to identify maintenance and repair requirements. Degradation of solar PV modules makes them less efficient, less reliable and, ultimately, inoperative. This paper reviews relevant literature to discuss:

  • Causes of efficiency reductions in photovoltaic cells

  • Ways to achieve long-term durability of …


A Proactive-Restoration Technique For Sdns, Ali Malik, Ruairí De Fréin Jun 2020

A Proactive-Restoration Technique For Sdns, Ali Malik, Ruairí De Fréin

Conference papers

Failure incidents result in temporarily preventing the network from delivering services properly. Such a deterioration in services called service unavailability. The traditional fault management techniques, i.e. protection and restoration, are inevitably concerned with service unavailability due to the convergence time that is required to achieve the recovery when a failure occurs. However, with the global view feature of software-defined networking a failure prediction is becoming attainable, which in turn reduces the service interruptions that originated by failures. In this paper, we propose a proactive restoration technique that reconfigure the vulnerable routes which are likely to be affected if the …


Remedying Sound Source Separation Via Azimuth Discrimination And Re-Synthesis, Ruairí De Fréin Jun 2020

Remedying Sound Source Separation Via Azimuth Discrimination And Re-Synthesis, Ruairí De Fréin

Conference papers

Commercially recorded music since the 1950s has been mixed down from many input sound sources to a two- channel reproduction of these sources. The effect of this approach is to assign sources to locations in a stereo field using a pan- position for each source. The Adress algorithm is a popular way of extracting individual music sound sources from a stereo mixture. A drawback of the Adress algorithm is that when time- frequency components in the stereo mixture are shared between two or more sources, calculating the inter-aural intensity scaling parameter for each source for that time-frequency component is challenging. …


New Robust Lpc-Based Method For Time-Resolved Morphology Of High-Noise Multiple Frequency Signals, Jin Xu, Ruairí De Fréin, Mark Davis Jun 2020

New Robust Lpc-Based Method For Time-Resolved Morphology Of High-Noise Multiple Frequency Signals, Jin Xu, Ruairí De Fréin, Mark Davis

Conference papers

This paper introduces a new time-resolved spectral analysis method based on the Linear Prediction Coding (LPC) method that is particularly suited to the study of the dynamics of low Signal-to-noise Ratio (SNR) signals comprising multiple frequency components. One of the challenges of the time-resolved spectral method is that they are limited by the Heisenberg-Gabor uncertainty principle. Consequently, there is a trade-off between the temporal and spectral resolution. Most of the previous studies are time-averaged methods. The proposed method is a parameterisation method which can directly extract the dominant formants. The method is based on a z-plane analysis of the poles …


Remedying Sound Source Separation Via Azimuth Discrimination And Re-Synthesis, Ruairí De Fréin Jun 2020

Remedying Sound Source Separation Via Azimuth Discrimination And Re-Synthesis, Ruairí De Fréin

Conference papers

Commercially recorded music since the 1950s has been mixed down from many input sound sources to a two-channel reproduction of these sources. The effect of this approach is to assign sources to locations in a stereo field using a pan-position for each source. The Adress algorithm is a popular way of extracting individual music sound sources from a stereo mixture. A drawback of the Adress algorithm is that when time-frequency components in the stereo mixture are shared between two or more sources, calculating the inter-aural intensity scaling parameter for each source for that time-frequency component is challenging. We show how …


Millimetre-Wave Planar Bruce Array Antenna, Zeeshan Ahmed, Manh Ha Hoang, Patrick Mcevoy, Max Ammann Feb 2020

Millimetre-Wave Planar Bruce Array Antenna, Zeeshan Ahmed, Manh Ha Hoang, Patrick Mcevoy, Max Ammann

Conference papers

A tri-band mm-wave planar Bruce array antenna for fifth generation communications (5G) is presented. The 16-element planar Bruce array antenna is simulated and fabricated on Rogers RT/Duroid 5880 substrate with thickness of 0.254 mm. For a compact and simple structure, the antenna has a highly directional fan-beam radiation pattern at broadside and peak realized gain of 14.0 dBi.


A Preliminary Study Of A Graphene Fractal Sierpinski Antenna, Alberto Boretti, Lorenzo Rosa, Jonathan Blackledge, Stefania Castelletto Jan 2020

A Preliminary Study Of A Graphene Fractal Sierpinski Antenna, Alberto Boretti, Lorenzo Rosa, Jonathan Blackledge, Stefania Castelletto

Conference papers

We provide a preliminary study of a Graphene fractal antenna operating at THz frequencies with the opportunity to modulate the emission. There are a number of advantages of the fractal design, namely multiband/wideband ability, and, a smaller, lighter and simpler configuration for higher gain, that can benefit from the coupling with Graphene, the thinnest and strongest of materials exhibiting very high electrical conductivity and tunability. This paper proposes a conceptual background for the study and presents some preliminary results on the electromagnetic emission simulations undertaken


A Statistically Significant Test To Evaluate The Order Or Disorder For A Binary String Of A Finite Length, Jonathan Blackledge, N. Mosola Jan 2020

A Statistically Significant Test To Evaluate The Order Or Disorder For A Binary String Of A Finite Length, Jonathan Blackledge, N. Mosola

Conference papers

—This paper addresses a basic problem in regard to the analysis of a finite binary string or bit stream (of compact support), namely, how to tell whether the string is representative of non-random or intelligible information (involving some form of periodicity, for example), whether it is the product of an entirely random process or whether it is something in between thetwo.Thisproblemhasapplicationsthatincludecryptanalysis, quantitative finance, machine learning, artificial intelligence and other forms of signal and image processing involving the general problem of how to distinguishing real noise from information embedded in noise, for example. After providing a short introductiontotheproblem,wefocusontheapplicationofinformation entropy for solving …


Digital Image Exchange Using A No-Key(S) Protocol With Phase-Only Encryption,, Jonathan Blackledge, N. Mosola Jan 2020

Digital Image Exchange Using A No-Key(S) Protocol With Phase-Only Encryption,, Jonathan Blackledge, N. Mosola

Conference papers

This paper considers an algorithm for transferring a digital image over an open network using a No-key(s) Protocol or Three-Way Pass and phase-only encryption/decryption. After providing a short study on the theoretical background to the method, an algorithm is presented on a step-by-step basis. Cryptanalysis is undertaken for the three intercept and single intercept cases, when it is assumed that the encrypted data is intercepted in its entirety for each pass or for any single pass, respectively. The algorithm focuses on the exchange of a JPEG image although in principle, the approach is independent of the format of the image …


Deep Learning Towards Intelligent Vehicle Fault Diagnosis, Mohammed Al-Zeyadi, Javier Andreu-Perez, Hani Hagras, Chris Royce, Darren Smith, Piotr Rzonsowski, Ali Malik Jan 2020

Deep Learning Towards Intelligent Vehicle Fault Diagnosis, Mohammed Al-Zeyadi, Javier Andreu-Perez, Hani Hagras, Chris Royce, Darren Smith, Piotr Rzonsowski, Ali Malik

Conference papers

Recently, the rapid development of automotive industries has given rise to large multidimensional datasets both in the production sites and after-sale services. Fault diagnostic systems are one of the services that the automotive industries provide. As a consequence of the rapid development of cars features, traditional rule-based diagnostic systems became very limited. Therefore, more sophisticated AI approaches need to be investigated towards more efficient solutions. In this paper, we focus on utilising deep learning so as to build a diagnostic system that is able to estimate the required services in an efficient and effective way. We propose a new model, …


Meaningful Age-Friendly Design. Case Studies On Enabling Assistive Technology., Matteo Zallio, Damon Berry, Larry J. Leifer Jan 2020

Meaningful Age-Friendly Design. Case Studies On Enabling Assistive Technology., Matteo Zallio, Damon Berry, Larry J. Leifer

Conference papers

The world population is steadily ageing and the World Health Organization recently stated that 8.5 percent of people worldwide are aged 65 and over. This cohort is projected to account for 1.6 billion people by 2050. Assistive Technology has been developed over previous decades with a particular aim to support people with disabilities. With the evolution of the market and the introduction of wearable technologies and IoT-based (Internet of Things) appliances, Assistive Technology has been influenced by the discipline of Age-Friendly Design, which has been applied to meaningfully improve the autonomy of a larger segment of the population, including older …


Modern Techniques For Discovering Digital Steganography, Michael Hegarty, Anthony Keane Jan 2020

Modern Techniques For Discovering Digital Steganography, Michael Hegarty, Anthony Keane

Conference papers

Digital steganography can be difficult to detect and as such is an ideal way of engaging in covert communications across the Internet. This research paper is a work-in-progress report on instances of steganography that were identified on websites on the Internet including some from the DarkWeb using the application of new methods of deep learning algorithms. This approach to the identification of Least Significant Bit (LSB) Steganography using Convolutional Neural Networks (CNN) has demonstrated some efficiency for image classification. The CNN algorithm was trained using datasets of images with known steganography and then applied to datasets with images to identify …


Re-Annotation Of Cough Events In The Ami Corpus, Paul Leamy, Damon Berry, David Dorran, Ted Burke Jun 2019

Re-Annotation Of Cough Events In The Ami Corpus, Paul Leamy, Damon Berry, David Dorran, Ted Burke

Conference papers

Cough sounds act as an important indicator of an individual's physical health, often used by medical professionals in diagnosing a patient's ailments. In recent years progress has been made in the area of automatically detecting cough events and, in certain cases, automatically identifying the ailment associated with a particular cough sound. Ethical and sensitivity issues associated with audio recordings of coughs makes it more difficult for this data to be made publicly available. However, without the public availability of a reliable database of cough sounds, developments in the area of audio event detection are likely to be hampered. The purpose …


Impact Of Loss Of Generation On Bus Voltage Frequency And Rocof, Damien Doheny, Michael Conlon Jan 2019

Impact Of Loss Of Generation On Bus Voltage Frequency And Rocof, Damien Doheny, Michael Conlon

Conference papers

This study investigates how the loss of a generator impacts bus voltage RoCoF post-disturbance. The results show that the fastest bus voltage RoCoFs will occur close to generators impacted the most by the disturbance but this may not be the closest generator to the disturbance. The study also demonstrates a simple method that can be used to identify the generator that will be impacted most after a disturbance and hence the network location that will experience the fastest RoCoF.


Series Compensation To Increase Power Flow: A Case Study On The Irish Transmission System, Aidan Heffernan, Jane Courtney Jan 2019

Series Compensation To Increase Power Flow: A Case Study On The Irish Transmission System, Aidan Heffernan, Jane Courtney

Conference papers

Ireland presents an interesting case study for transmission network strengthening. The majority of load in the country is located at the nation's capital, Dublin, in the East, while most of the new conventional generation and renewable generation are found in the South-West. Power is transferred between the two via a 400 kV network. This leads to large cross- country power flows. This power distribution disparity is due to increase. A large thermal generating station which is connected to the 400 kV system in the West, will close by 2025. This generation will be replaced partially with wind generation in the …


Impact Of Consumer Profiles On A Consumer Convenience Prioritised Demand Response, Chittesh Veni Chandran, Keith Sunderland, Malabika Basu Jan 2019

Impact Of Consumer Profiles On A Consumer Convenience Prioritised Demand Response, Chittesh Veni Chandran, Keith Sunderland, Malabika Basu

Conference papers

Distribution network (DN) load flexibility has simultaneously created challenges and opportunities. The major challenge is to meet the demand-supply balance while maintaining a positive profit-loss ratio. Further, Government enforced climate change policies attract low carbon technology (LCT) distributed energy resources (DER), which further complicate matters. Along with DN, the domestic appliance industry has undergone drastic modernization leading to appliances with advanced control and power efficient technologies as well as automation capabilities. This paper proposes a demand response (DR) program that facilitates these advancements while micromanaging the domestic load consumption pattern so as to manage peak demand in the network. This …


Sliding Mode Control Strategy For Three-Phase Three-Level T-Type Shunt Active Power Filters, Hasan Komurcugil, Sertac Bayhan, Samet Biricik Jan 2019

Sliding Mode Control Strategy For Three-Phase Three-Level T-Type Shunt Active Power Filters, Hasan Komurcugil, Sertac Bayhan, Samet Biricik

Conference papers

In this paper, a sliding mode control (SMC) strategy is proposed for three-phase three-level T-type shunt active power filters (SAPF). The proposed control strategy has the ability to balance the capacitor voltages with respect to the neutral-point. The proposed SMC strategy is formulated in the natural frame which eliminates abc/dq transformation and two PI controllers compared to the design in the dq frame. In natural frame, only one PI controller is needed to generate the amplitude of grid current reference. The output of the PI controller is multiplied by the unity sinusoidal waveforms, obtained from the grid voltages, so as …


Reliability Issues Caused By The Retirement Of Large Thermal Generation Facilities: An Irish Case Study, Kyle Lawson, Jane Courtney Jan 2019

Reliability Issues Caused By The Retirement Of Large Thermal Generation Facilities: An Irish Case Study, Kyle Lawson, Jane Courtney

Conference papers

Like all developed countries Ireland faces increasing pressure to reduce their carbon footprint. Part of the governments plans include the scaling back of fossil fuel generation facilities and increasing renewable resources. Moneypoint is Irelands only coal fired generation station. In 2025 Moneypoint is due to reach the end of its life cycle. At this point the Irish government will have to make a decission on the future of the generation facility. Currently Moneypoint is responsible for the generation of approximately 10 % of Irelands energy needs. In this paper, the removal of Moneypoint from the Irish generation portfolio will be …