Ivan Glesk

University of Strathclyde · Department of Electronic and Electrical Engineering (EEE)

Many techniques have been studied for recovering information from shared media such as optical fiber that carries different types of communication, sensing, and data streaming. This article focuses on a simple method for retrieving the targeted information with the least necessary number of significant samples when using statistical population samp...

Silicon nitride (Si3N4) is an ideal candidate for the development of low-loss photonic integrated circuits. However, efficient light coupling between standard optical fibers and Si3N4 chips remains a significant challenge. For vertical grating couplers, the lower index contrast yields a weak grating strength, which translates to long diffractive st...

This paper describes design, theoretical analysis, and experimental evaluation of a π-Phase-Shifted Fiber Bragg Grating (π-PSFBG) inscribed in the standard telecom fiber for slow light generation. At first, the grating was designed for its use in the reflection mode with a central wavelength of 1552 nm and a pass band width of less than 100 pm. The...

Cybersecurity and cyber resilience are becoming crucial for many industries especially in the era of digital transformation. In this work, we report on the security analysis of the physical layer of OCDMA networks based on 2-D codes such as fast frequency-hopping (FFH). We analyze eavesdropping in OCDMA networks using FFH codes spread in both, time...

High data rate coverage, security, and energy efficiency will play a key role in the continued performance scaling of next-generation mobile systems. Dense, small mobile cells based on a novel network architecture are part of the answer. Motivated by the recent mounting interest in free-space optical (FSO) technologies, this paper addresses a novel...

The telecommunications data transfer in single-mode (SM) optical fiber (OF) of a passive optical network (PON) is managed by dynamic bandwidth allocation (DBA). In most internet of things (IoT) sensor network applications, both raw sensing signals and telecommunication data are transmitted in SM OFs, too. At the present time, this is not done in a...

Energy-efficient devices will play a key role in the continued performance scaling of next-generation information and communications technology systems. Graphene has emerged as a key optoelectronic material with unique energy-like properties. But to the best of our knowledge, these advantages have not yet been fully exploited in optical modulators...

This paper targets a dynamic statistical threshold detection algorithm of fiber Bragg grating (FBG) spectral peaks at the presence of changing Signal-to-Noise Ratio ( SNR ) in an optical fiber of a sensing application. The proposed post-demodulation SNR -based detection implements sliding window technique. Its detection threshold is adapted by the...

This paper targets a dynamic statistical threshold detection algorithm of fiber Bragg grating (FBG) spectral peaks at the presence of changing Signal-to-Noise Ratio ( SNR ) in an optical fiber of a sensing application. The proposed post-demodulation SNR -based detection implements sliding window technique. Its detection threshold is adapted by the...

This paper targets a Denoising Dynamic Statistical Threshold (DDST) detection algorithm to detect the “presence” of Fiber Bragg Grating (FBG) spectral peaks in noise with changing Signal-to-Noise Ratio (SNR) in a sensing channel. Computing the DDST is based on statistical parameters of the background noise. The DDST is determined by adjusting it us...

In this proof-of-principle paper, the application of 2-D optical code-division multiple-access (OCDMA) modulation to long-range automotive time-of-flight (ToF) light detection and ranging (LiDAR) is studied. The regulations and physical constraints that govern the design parameters are reviewed. Using 2-D carrier-hopping prime codes (CHPCs), the mo...

The growing demand for extensive and reliable structural health monitoring resulted in the development of advanced optical sensing systems (OSS) that in conjunction with wireless optical networks (WON) are capable of extending the reach of optical sensing to places where fibre provision is not feasible. To support this effort, the paper proposes a...

This work addresses a transmitter based on a RTD oscillator operating at 1.03 THz supporting output power and capacity as high as 0.84 mW and 0.15 Tb/s whilst achieving a 7- meter THz link reach.

Polarization mode dispersion is recognized as a key factor limiting optical transmission systems, particularly those fiber links that run at bit rates beyond 10 Gbps. In-line test and characterization of polarization mode dispersion are thus of critical importance to evaluate the quality of installed optical fibers that are in use for high-speed si...

This paper investigates for the first time how the implementation of semiconductor optical amplifier (SOA)-based devices in photonic networks can negatively impact the integrity of two-dimensional wavelength-hopping time-spreading (2D-WH/TS) optical code-division multiple access (OCDMA) codes based on multi-wavelength picosecond code carriers. It i...

Free Access Link: https://lnkd.in/dNzVMcX Non-domestic buildings contribute 20% of the UK's annual carbon emissions. A contribution exacerbated by its ageing stock of which only 7% is considered new-build. Consequently, the government has set regulations to decrease the amount of energy take-up by buildings which currently favour deep energy retro...

Machine learning (ML) has been recognised as a powerful method for modelling building energy consumption. The capability of ML to provide a fast and accurate prediction of energy loads makes it an ideal tool for decision-making tasks related to sustainable design and retrofit planning. However, the accuracy of these ML models is dependent on the se...

Particle swarm optimization (PSO) is a swarm-based optimization technique capable of solving different categories of optimization problems. Nevertheless, PSO has a serious exploration issue that makes it a difficult choice for multi-objectives constrained optimization problems (MCOP). At the same time, Multi-Protocol Label Switched (MPLS) and its e...

Temperature dependence is one of the main challenges of the silicon-on-insulator platform due to the large thermo-optic coefficient of its core material. In this work we propose a design of an all-passive athermal silicon-on-insulator Mach-Zehnder interferometer (MZI) based on the standard silicon material platform. The MZI's temperature compensati...

Particle swarm optimization (PSO) is a swarm-based optimization technique capable of solving different categories of optimization problems. Nevertheless, PSO has a serious exploration issue that makes it a difficult choice for multi-objectives constrained optimization problems (MCOP). At the same time, MultiProtocol Label Switched (MPLS) and its ex...

Due to increasing demands for the more accurate structural health monitoring of large-scale facilities, e.g. modern high-speed railways and bridges, there is a huge uptake in the development of optical sensor networks (OSN), which can help mitigate issues with conventional electric sensors, especially their sensitivity to electromagnetic interferen...

Recent studies show that temperature variation in ultrafast incoherent fiber-optic code-division multiple-access (FO-CDMA) systems using picosecond multiwavelength codes is a realistic problem even though dispersion-compensating fiber is utilized. The phenomenon creates distortions in auto- and cross-correlation functions and then worsens system pe...

A technique for the characterization of picosecond pulse widths is presented, based a non-linear optical fiber loop mirror and power meter measurement. Pulse-widths in the 2-10ps range are successfully recovered with a resolution of 0.25ps.

There have been numerous simulation tools utilised for calculating building energy loads for efficient design and retrofitting. However, these tools entail a great deal of computational cost and prior knowledge to work with. Machine Learning (ML) techniques can contribute to bridging this gap by taking advantage of existing historical data for fore...

A method for measuring picosecond pulse width by using only fiber components and optical power meters is presented. We have shown that the output power splitting ratio of a non-linear fiber loop mirror can be used to extract the full-width half maximum of the optical pulse, assuming a known slowly varying envelope shape and internal phase structure...

The real-time properties and operational constraints of Wireless Sensor Networks (WSNs) have emerged the need for designing energy efficient routing protocols. Recently, software defined network based WSN (SDN-WSN) emerging technology has offered a significant development by untying control logic plane from the low power sensor nodes. This centrali...

Abstract Ever growing population and progressive municipal business demands for constructing new buildings are known as the foremost contributor to greenhouse gasses. Therefore, improvement of energy efficiency of the building sector has become an essential target to reduce the amount of gas emission as well as fossil fuel consumption. One most eff...

Subwavelength grating (SWG) waveguides in silicon-on-insulator are emerging as an enabling technology for implementing compact, high-performance photonic integrated devices and circuits for signal processing and sensing applications. We provide an overview of recent work on developing wavelength selective SWG waveguide filters based on Bragg gratin...

To preserve the integrity of fiber transmission in incoherent systems using picosecond carriers the chromatic dispersion must be controlled with the high accuracy. This can be very challenging task especially in a multiwavelength environment under varying conditions. Under these circumstances the tunability of the control mechanism is desired. In t...

It is believed that an all-optical signal processing based on advanced integrated devices (passive, active or both) would play an important role in future multiplexing systems. In this paper we discuss approaches and techniques we have developed and demonstrated for improving the scalability and performance of Optical Code Division Multiplexing (OC...

Chromatic and temperature induced dispersion can both severely affect incoherent high data rate communications in optical fibre. This is certainly also true for incoherent optical code division multiple access (OCDMA) systems with multi-wavelength picosecond code carriers. Here, even a relatively small deviation from a fully dispersion compensated...

In order to preserve the performance of incoherent OCDMA systems it is imperative to maintain the width of the OCDMA auto-correlation function. This can be challenging in OCDMA systems when using multi-wavelength pico-second pulses as code carriers. In this respect, a Semiconductor Optical Amplifier (SOA) was used to control the chirp of OCDMA code...

Over the last decades, the internet traffic has been rapidly growing resulting in Terabits per second aggregate data throughputs. We have also been witnessing that the electronic signal processing the way it is known today is approaching its limitations due to a grooving manifestation of the electronic bottleneck. It is believed that the ultra-fast...

The nonlinear optical loop mirror (NOLM) has been studied for several decades and has attracted considerable attention for applications in high data rate optical communications and all-optical signal processing. The majority of NOLM research has focused on silica fiber-based implementations. While various fiber designs have been considered to incre...

A multifunctional sensor that responds to all – static/quasi-static or dynamic temperature or force – is reported. The sensor is based on a ferroelectric poly(vinylidene fluoride trifluoroethylene) (P(VDF-TrFE)) capacitor connected to the gate of organic field-effect transistor (OFET). Both, the P(VDF-TrFE) capacitance and the output voltage of the...

Modern communication networks offer advance and diverse applications, which require huge usage of network resources while providing quality of services to the users. Advance communication is based on multiple switched networks that cannot be handle by traditional IP (internet protocol) networks. GMPLS (Generalized multiprotocol label switched) netw...

Experimental investigation has been conducted on the influence of optical fiber temperature variations on Two Dimension Wavelength/Hopping Time/Spreading Incoherent Optical Code Division Multiple Access (2D-WH/TS iOCDMA) codes. Our experimental results show that in the literature reported approaches assuming a temperature induced coefficient Dtemp...

We have experimentally investigated the influence of temperature on the OCDMA auto-correlation recovered after transmission in an optical fiber link when exposed to different temperature settings. The OCDMA system uses two dimensional wavelength-hopping time-spreading (2D-WH/TS) codes based on picosecond multi-wavelength pulses. To the best of our...

In this paper, double weight zero cross correlation (DW-ZCC) code is proposed for spectral amplitude coding optical code division multiple access (SAC–OCDMA) system. DW-ZCC takes the advantages of two previously proposed SAC-codes namely modified double weight (MDW) and zero-cross correlation (ZCC) codes, while providing optimized code length and m...

Introduction of modern and diverse applications in telecommunication field has raised challenges in networking area regarding efficient use of network resources and with optimizing performance. Therefore MPLS/GMPLS (Generalized multi-protocol label switching) networks were introduced to provide a better quality of service to meet users' requirement...

The emergence of heterogeneous data traffic such as voice over IP, video streaming and online gaming have demanded networks with capability of supporting quality of service (QoS) at the physical layer with traffic prioritisation. This paper proposes a new variable-weight code based on spectral amplitude coding for optical code-division multiple-acc...

Modern telecommunication networks are based on diverse applications that highlighted the status of efficient use of network resources and performance optimization. Various methodologies are developed to address multi-objectives optimization within the traffic engineering of MPLS/ GMPLS networks. However, Pareto based approach can be used to achieve...

Knowledge of an amputees' residual limb skin temperature is considered to be of particular importance as an indicator of tissue health. Temperature within the prosthetic socket typically varies over the range 25 °C to 35 °C and this warm, confined environment causes sweating which creates favourable conditions for both the growth of bacteria and an...

Distortion of the optical code division multiple access (OCDMA) auto-correlation width by fiber chromatic dispersion can severely influence incoherent OCDMA transmission based on picosecond multiwavelength pulses. To the best of our knowledge, we report for the first time the use of a semiconductor optical amplifier (SOA) for manipulation of the OC...

A novel approach for improving the number of simultaneous users in a hybrid OCDMA-OTDMA network is proposed and analysed. OCDMA system is based on two-dimensional wavelength-hopping time-spreading codes with multi-wavelengths picosecond carriers. The scalability increase was achieved by adding a third dimension to separate OCDMA user groups within...

Dispersion has very strong detrimental effects on high data rate incoherent transmission systems. Situation gets much worse when data bits become only a few picoseconds long. In this paper we investigate how the dispersion can affect an optical auto-correlation function in optical code division multiple access (OCDMA) systems when data are carried...

Wireless communication is a telecommunication technology, which enables wireless transmission between the portable devices to provide wireless access in all types of environments. In this research, the measurements and various empirical models are analysed and compared in order to find out a suitable propagation model to provide guidelines for cell...

In this paper, a pulse-shift technique, which divides every time slot (or chip) into equal-width sub-chips, is used to model the effect of fiber temperature fluctuations in incoherent (asynchronous) optical code-division multiple-access (O-CDMA) systems. With the advances in all-optical thresholding technology, power detection of ultrashort optical...

This paper shows that FSO could be an option for backhauling among microcells in future 5G systems in areas where fog is not a concern as very short LOS links (few hundred meters) would be required. In this respect, monthly CCDFs of rain attenuation at both RF (28 GHz) and optical bandwidth have been calculated in the area of Hyderabad (Pakistan)....

This paper investigates fault location techniques in high voltage direct current (HVDC) transmission networks utilizing voltage source converters (VSCs). The subject has been extensively researched due to the fault locating actions associated with the supply restoration and the economic loss, and also because of the trending employment of VSC-HVDC...

We review recent work on all-optical signal processing in silicon photonics. In particular, we describe the integration of a nonlinear optical loop mirror in silicon-on-insulator for applications including wavelength conversion, NRZ-to-RZ modulation format conversion, and optical time-division de-multiplexing.

In network communication field, routing protocols have got a significant role which are not only used in networks to handle the user data but also monitors the various network limitations. Dynamic routing protocols such as OSPF, EIGRP and RIP are used for forwarding user data to its destination by instantly detecting the network limitations. These...

Wearable systems for prosthetic users have to be designed such that the sensors are minimally obtrusive and reliable enough to faithfully record movement and physiological signals. A mobile sensor platform has been developed for use with lower limb prosthetic users. This system uses an Arduino board that includes sensors for temperature, gait, orie...

In many areas of the world accessing professional physicians ‘when needed/as needed’ might not be always possible for a variety of reasons. Therefore, in such cases a targeted e-Health solution to safeguard patient long-term health could be a meaningful approach. Today’s modern healthcare technologies, often built around electronic and computer-bas...

In the modern communication networks, where increasing user demands and advance applications become a challenging task for handling user traffic. Routing protocols have got a significant role not only to route user data across the network but also to reduce congestion with less complexity. Dynamic routing protocols such as OSPF, RIP and EIGRP were...

An optical true time delay line (OTTDL) is a basic photonic building block that enables many microwave photonic and optical processing operations. The conventional design for an integrated OTTDL that is based on spatial diversity uses a length-variable waveguide array to create the optical time delays, which can introduce complexities in the integr...

Monitoring of the interface temperature at skin level in lower-limb prosthesis is notoriously complicated. This is due to the flexible nature of the interface liners used impeding the required consistent positioning of the temperature sensors during donning and doffing. Predicting the in-socket residual limb temperature by monitoring the temperatur...

In ultra-high speed incoherent optical communication systems chromatic dispersion is considered a key impairment. Tuneable dispersion compensation for the signal data ultra-short carrier pulses propagated through the fibre optic cable is an effective way of overcoming this problem. The transmission system performance could be improved by manipulati...

Track monitoring systems are a fundamental part of railroad safety. With the electrification and development of train traction control electronics, levels of electromagnetic interference (EMI) close to railroad monitoring systems are reaching critical levels. Unreliable track safety and fault monitoring systems could affect the efficient and safe f...