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Articles 361 - 390 of 564
Full-Text Articles in Electrical and Computer Engineering
Enhanced Refractometer Based On Periodically Tapered Small Core Singlemode Fiber, Pengfei Wang, Gilberto Brambilla, Ming Ding, Timothy Lee, Lin Bo, Yuliya Semenova, Qiang Wu, Gerald Farrell
Enhanced Refractometer Based On Periodically Tapered Small Core Singlemode Fiber, Pengfei Wang, Gilberto Brambilla, Ming Ding, Timothy Lee, Lin Bo, Yuliya Semenova, Qiang Wu, Gerald Farrell
Articles
Abstract—An all-fiber 1 refractive index (RI) sensor with a 2 simple configuration of periodical tapers is proposed and inves3 tigated experimentally. The proposed fiber RI sensor consists of 4 a small core fiber sandwiched between two standard singlemode 5 fibers, with tapers periodically fabricated along the small core 6 fiber using a focused CO2 laser beam. Such a structure can be 7 used for RI sensing by measuring the dip wavelength shift of 8 the multimode interference within the small core fiber cladding. 9 An average sensitivity of 226.6 nm/RIU (RI Unit) has been 10 experimentally achieved in the RI …
A Silica Single-Mode Fibre-Chalcogenide Multimode Fibre-Silica Single-Mode Fibre Structure, Pengfei Wang, Ming Ding, Lin Bo, Yuliya Semenova, Qiang Wu, Gerald Farrell
A Silica Single-Mode Fibre-Chalcogenide Multimode Fibre-Silica Single-Mode Fibre Structure, Pengfei Wang, Ming Ding, Lin Bo, Yuliya Semenova, Qiang Wu, Gerald Farrell
Articles
In this letter we theoretically and experimentally investigate a single-mode-multimode-single-mode (SMS) structure based on chalcogenide (As2S3) multimode fibre and silica single-mode fibres. The experimental results show a general agreement with the numerical simulation results based on a wide angle-beam propagation method (WA-BPM). Multimode interference variation was observed as a result of photo-induced refractive index changes arising from either localized laser irradiation at a wavelength of 405 nm or the use of a UV lamp. Our result provides a platform for the development
Influence Of Fluctuations Of The Geometrical Parameters On The Photonic Band Gaps In One-Dimensional Photonic Crystals, Vladimir A. Tolmachev, Anna .. Baldycheva, Kevin Berwick, Tatiana Perova
Influence Of Fluctuations Of The Geometrical Parameters On The Photonic Band Gaps In One-Dimensional Photonic Crystals, Vladimir A. Tolmachev, Anna .. Baldycheva, Kevin Berwick, Tatiana Perova
Articles
The influence of random fluctuations in the layer thicknesses in high contrast, one-dimensional Photonic Crystals (PCs) on the transmission spectra and Photonic Band Gaps (PBGs) is investigated. The change in the PBGs depends on the magnitude of the fluctuations and increases with an increase in the order of the PBG. Introducing thickness non-uniformity into the PC of up to 0.004 times the value of lattice constant for different types of fluctuation distributions has a negligible effect on either the position or the shape of the 1st and nearest PBGs. The approach suggested here allows the determination of the tolerances required …
A Teaching Practice Review Of The Use Of Multiple-Choice Questions For Formative And Summative Assessment Of Student Work On Advanced Undergraduate And Postgraduate Modules In Engineering, Aidan O'Dwyer
Articles
This paper reflects on, reports on and evaluates the use of multiple-choice questions, in both formative and summative assessment modes, on control engineering modules taken by advanced undergraduate and postgraduate engineering students, over four academic years. The material covered by the modules is analytical in nature. The rationale for examining the assessment strategy was the poor performance by students in a closed book traditional terminal examination on one of the advanced undergraduate modules over some years. The change in assessment strategy has improved student learning, as measured by assessment data; student feedback on the assessment methods is broadly positive. The …
Upqc For Power Quality Improvement In Dg Integrated Smart Grid Network: A Review, Shafiuzzaman Khadem, Malabika Basu, Michael Conlon
Upqc For Power Quality Improvement In Dg Integrated Smart Grid Network: A Review, Shafiuzzaman Khadem, Malabika Basu, Michael Conlon
Articles
Quality of power supply has become an important issue with the increasing demand of Distributed Generation (DG) systems either connected to the grid through some power electronics grid-tie inverters or to work in isolated (microgrid) mode towards the development of a smart grid network. In this paper a technical review of Integration of Unified Power Quality Conditioner (UPQC) in Distributed Generation Network has been presented. Though the primary task of UPQC is to minimize the grid voltage and load current disturbance along with the reactive and harmonic power compensation, additional functionalities like compensation of voltage interruption and active power transfer …
Properties Of Non-Tilted Bent-Core Orthogonal Smectic Liquid Crystal, S. Sreenilayam, M. Nagaraj, Yuri Panarin, J. K. Vij, A. Lehmann, C. Tschierske
Properties Of Non-Tilted Bent-Core Orthogonal Smectic Liquid Crystal, S. Sreenilayam, M. Nagaraj, Yuri Panarin, J. K. Vij, A. Lehmann, C. Tschierske
Articles
We present the properties of different achiral orthogonal polar smectic phases observed in a homologous series of bent-core molecular compounds. The macroscopically uniaxial SmAPR phase transforms to biaxial state by the application of higher electric fields and biaxial SmAPA phase undergoes biaxial-uniaxial-biaxial texture transformation with increasing electric fields,i.e.,initial antiferroelectric structure transforms into ferroelectric state under higher electric fields and it shows three different optically distinguishable states. The SmAPAR phase shows an entirely different response compared to other polar smectic phases under study. The dielectric measurements in the SmAPAR phase is the evidence of antiferroelectric behavior of uniaxial state. The polarizing …
Wind Resource In The Urban Environment, Jonathan Blackledge, Eugene Coyle, Derek Kearney, Eamonn Murphy, Maria-Jose Rivas Duartes
Wind Resource In The Urban Environment, Jonathan Blackledge, Eugene Coyle, Derek Kearney, Eamonn Murphy, Maria-Jose Rivas Duartes
Articles
The World Meteorological Organization (WMO) Commission for Instruments and Methods of Observation recognized the need to include in the 1996 WMO Guide to Instruments and Methods of Observation, WMO No. 8 a new chapter on Urban Observations (Oke 2006). There is an increasing demand for meteorological data to support building and urban design, energy conservation, micro -wind turbine installation, air quality, pollution control, insurance, wind engineering, etc. Over the last six years instrumentation has been installed at the Dublin Ins titute of Technology (DIT) in two separate locations to monitor the wind. Research has shown that the wind resource will …
Non-Gaussian Anisotropic Diffusion Processing For Medical Imagining Using The Osirix Dicom Viewer, Jonathan Blackledge, Matthew Blackledge, Jane Courtney
Non-Gaussian Anisotropic Diffusion Processing For Medical Imagining Using The Osirix Dicom Viewer, Jonathan Blackledge, Matthew Blackledge, Jane Courtney
Articles
Medical imaging is a fertile area for computer graphics, image processing and real time visualization. In this paper we present a method for reducing noise in CT (Computed Tomography) and MR (Magnetic Resonance) images that (in addition to other noise sources) is characteristic of the numerical procedures required to construct the images, namely, the (inverse) Radon Transform. In both cases, MR imaging in particular, an additional noise source is due to the process of diffusion thereby predicating use of the Anisotropic Diffusion method for noise suppression. This method is based on a diffusion model for noise generation where the Diffusivity …
Energy Commodities Trading Using A Phase Signal Derived From The Levy Index Of Price And Volatility, Jonathan Blackledge, Derek Kearney, Claire Farrell, Grace Kearney
Energy Commodities Trading Using A Phase Signal Derived From The Levy Index Of Price And Volatility, Jonathan Blackledge, Derek Kearney, Claire Farrell, Grace Kearney
Articles
Energy traders need to decide what markets and commodities to trade in, when to open and close trades and how to maximize profits. In this paper we consider an approach for analyzing energy commodity price data based on the Lévy index in order to develop a new short-term predictive trend indicator for the price. This is achieved by computing the unwrapped phase signal generated from the Lévy index of both the Stochastic Volatility and price and is evaluated using data from the Irish Energy Market, namely, time series for the price of Electricity, Gas and Oil. The initial results show …
Structure And Polymorphism Of Biaxial Bent-Core Smectic Liquid Crystal, S. Sreenilayam, M. Nagaraj, Yuri Panarin, J. K. Vij, A. Lehmann, C. Tschierske
Structure And Polymorphism Of Biaxial Bent-Core Smectic Liquid Crystal, S. Sreenilayam, M. Nagaraj, Yuri Panarin, J. K. Vij, A. Lehmann, C. Tschierske
Articles
The mesomorphic properties of a homologous series of achiral bent-core compounds are studied by polarizing optical microscopy, electro-optics and polarization measurements. Induction of a new orthogonal smectic phases with the increase of alkyl side chain length was observed. One of the compounds exhibits a unique phase transition between four non-tilted smectic phases (SmAPA–SmAPAR-SmAPR-SmA). The uniaxial but antiferroelectric nature of SmAPAR phase was confirmed by POM, current response, the 2nd harmonic electro-optic response and polarization measurements. The structure of SmAPAR phase was studied theoretically by Next-Nearest-Neighbor model and was identified as SmAPα.
Light Coupling Between A Singlemode-Multimode-Singlemode (Sms) Fiber Structure And A Long Period Fiber Gating, Qiang Wu, Yuliya Semenova, Youqiao Ma, Pengfei Wang, Tuan Gao, Long Jin, Gerald Farrell
Light Coupling Between A Singlemode-Multimode-Singlemode (Sms) Fiber Structure And A Long Period Fiber Gating, Qiang Wu, Yuliya Semenova, Youqiao Ma, Pengfei Wang, Tuan Gao, Long Jin, Gerald Farrell
Articles
A Microfiber Cavity With Minimal-Volume Confinement, Ming Ding, Pengfei Wang, Timothy Lee, Gilberto Brambilla
A Microfiber Cavity With Minimal-Volume Confinement, Ming Ding, Pengfei Wang, Timothy Lee, Gilberto Brambilla
Articles
Monofilar Spiral Slot Antenna For Dual-Frequency Dual-Sense Circular Polarization, Xiulong Bao, Max Ammann
Monofilar Spiral Slot Antenna For Dual-Frequency Dual-Sense Circular Polarization, Xiulong Bao, Max Ammann
Articles
A dual-band antenna with right-hand circular polarization for the first frequency and the counter polarization at the second frequency is realized with compact printed spiral slots. The coupled spiral slots are fed by a 50 Ω microstrip line. Dual-sense circularly-polarized performance is achieved by realizing oppositely-directed current rotation for the two frequency bands. A parametric study shows that the additional slot significantly improves the bandwidth for both frequency bands. Measured results show that the fractional impedance bandwidth is greater than 18% for both bands. The 3 dB axial-ratio bandwidths are 4.5% and 3.5% for the RHCP and LHCP bands, respectively.
Wideband Dual-Frequency Dual-Polarized Dipole-Like Antenna, Xiulong Bao, Max Ammann
Wideband Dual-Frequency Dual-Polarized Dipole-Like Antenna, Xiulong Bao, Max Ammann
Articles
A wideband dual-frequency dual-polarized printed antenna is proposed for LTE, WLAN, and UWB systems. The dual-band antenna provides wide impedance bandwidths of 74% with respect to the center frequency of 2.725 GHz, and 39% with respect to the center frequency of 7.15 GHz. An open slot in the ground plane between the feed arms provides an orthogonal path to realize an embedded circularly polarized band at 2.35 GHz with an axial-ratio bandwidth of 16%. Dual-band characteristics are achieved by an asymmetrical dipole-like element and the coupling configuration between the T-shaped feed line and the wide ground-plane slot.
Enhancing The Performance Of Building Integrated Photovoltaics, Brian Norton, Philip C. Eames, Tapas K. Mallick, Ming Jun Huang, Sarah J. Mccormack, Jayanta D. Mondol, Yigzaw G. Yohanis
Enhancing The Performance Of Building Integrated Photovoltaics, Brian Norton, Philip C. Eames, Tapas K. Mallick, Ming Jun Huang, Sarah J. Mccormack, Jayanta D. Mondol, Yigzaw G. Yohanis
Articles
Recent research in Building Integrated Photovoltaics (BIPV) is reviewed with the emphases on a range of key systems whose improvement would be likely to lead to improved solar energy conversion efficiency and/or economic viability. These include invertors, concentrators and thermal management systems. Advances in techniques for specific aspects of systems design, installation and operation are also discussed.
A Simple Ultrasensitive Displacement Sensor Based On A High Bend Loss Single-Mode Fibre And A Ratiometric Measurement System, Pengfei Wang, Gilberto Brambilla, Yuliya Semenova, Qiang Wu, Gerald Farrell
A Simple Ultrasensitive Displacement Sensor Based On A High Bend Loss Single-Mode Fibre And A Ratiometric Measurement System, Pengfei Wang, Gilberto Brambilla, Yuliya Semenova, Qiang Wu, Gerald Farrell
Articles
Printed Circularly-Polarized Antenna With Ultra-Wide Axial-Ratio Bandwidth, Xiulong Bao, Max Ammann
Printed Circularly-Polarized Antenna With Ultra-Wide Axial-Ratio Bandwidth, Xiulong Bao, Max Ammann
Articles
A circularly polarised printed dipole-like antenna employing asymmetrical arms and an orthogonal slit in the ground plane is presented. It is fed by a stepped microstrip line which connects to the shorter arm. By utilising surface currents on the asymmetrical arms and the orthogonal feedline structure, circular polarisation is realised. Experimental and numerical data are in agreement and the measured results show a fractional impedance bandwidth of 41.3% (1.77–2.69 GHz) and a wide axial-ratio bandwidth of 38.4% (1.81–2.67 GHz).
Humidity Sensor Based On A Single-Mode Hetero-Core Fiber Structure, Qiang Wu, Yuliya Semenova, Jinesh Mathew, Pengfei Wang, Gerald Farrell
Humidity Sensor Based On A Single-Mode Hetero-Core Fiber Structure, Qiang Wu, Yuliya Semenova, Jinesh Mathew, Pengfei Wang, Gerald Farrell
Articles
Using a small-core single-mode fiber (SCSMF), a novel relative humidity (RH) sensor based on an SMF28-SCSMFSMF28 fiber structure was proposed in this paper. By depositing a humidity sensitive material, such as poly (ethylene oxide) (PEO) on the bare SCSMF fiber, the proposed structure can act as an RH sensor with high sensitivity. Experiments demonstrated that the proposed RH sensor with PEO coating can achieve a sensitivity of 430nm per relative humidity unit (RHU) in the RH range from 80% to 83% RH and a sensitivity of 50nm per RHU in the RH range from 83% to 95% RH.
Measured Performance Of A 1.72 Kw Rooftop Grid Connected Photovoltaic System In Ireland, Lacour Ayompe, Aidan Duffy, Sarah Mccormack, Michael Conlon
Measured Performance Of A 1.72 Kw Rooftop Grid Connected Photovoltaic System In Ireland, Lacour Ayompe, Aidan Duffy, Sarah Mccormack, Michael Conlon
Articles
This paper presents results obtained from monitoring a 1.72 kWp photovoltaic system installed on a flat roof of a 12 m high building in Dublin, Ireland (latitude 53.4 N and longitude 6.3 E). The system was monitored between November 2008 and October 2009 and all the electricity generated was fed into the low voltage supply to the building. Monthly average daily and annual performance parameters of the PV system evaluated include: final yield, reference yield, array yield, system losses, array capture losses, cell temperature losses, PV module efficiency, system efficiency, inverter efficiency, performance ratio and capacity factor. The maximum solar …
Transparent Patch Antenna On A-Si Thin Film Glass Solar Module, Maria Roo Ons, S. Shynu, Max Ammann, Sarah Mccormack, Brian Norton
Transparent Patch Antenna On A-Si Thin Film Glass Solar Module, Maria Roo Ons, S. Shynu, Max Ammann, Sarah Mccormack, Brian Norton
Articles
An optically transparent microstrip patch mounted on the surface of a commercially available solar module is proposed. The patch comprises a thin sheet of clear polyester with a conductive coating. The amorphous silicon solar cells in the module are used as both photovoltaic generator and antenna ground plane. The proposed structure provides a peak gain of 3.96 dBi in the 3.4-3.8 GHz range without significantly compromising the light transmission in the module. A comparison between copper and transparent conductors is made in terms of antenna and solar performance. The proposed technique is considerably simpler that previous integration approaches.
Influence Of Angular Orientation Of The Embedded Highly Birefringent Fiber On Pmd Changes Under Axial Stress, Daniel Budaszewski Daniel Budaszewski, Piotr Lesiak, Robert Plaga, Ginu Rajan, Yuliya Semenova, Gerald Farrell, Anna Boczkowska, Andrzej W. Domanski's, Tomasz R. Woliński
Influence Of Angular Orientation Of The Embedded Highly Birefringent Fiber On Pmd Changes Under Axial Stress, Daniel Budaszewski Daniel Budaszewski, Piotr Lesiak, Robert Plaga, Ginu Rajan, Yuliya Semenova, Gerald Farrell, Anna Boczkowska, Andrzej W. Domanski's, Tomasz R. Woliński
Articles
In the paper we present results of the research on polarization mode dispersion changes inside the polarimetric optical fiber sensors based on highly birefringent optical fibers embedded into composite materials with different angular orientations of the optical axes. Based on measurements made for different types of highly birefringent optical fiber sensors we have shown that strain sensitivities after lamination process are different in comparison to the data obtained before lamination. Our results indicate that polarization mode dispersion in side-hole highly birefringent fibers under axial stress strongly depends on fiber orientation in the composite material suggesting that orientation of the polarization …
Experimental Demonstration Of An All-Fiber Variable Optical Attenuator Based On Liquid Crystal Infiltrated Photonic Crystal Fiber, Sunish Mathews, Gerald Farrell, Yuliya Semenova
Experimental Demonstration Of An All-Fiber Variable Optical Attenuator Based On Liquid Crystal Infiltrated Photonic Crystal Fiber, Sunish Mathews, Gerald Farrell, Yuliya Semenova
Articles
The application of a nematic liquid crystal infiltrated solid core Photonic Crystal Fiber as a novel all-fiber in-line electronically controlled broadband fiber optic attenuator in the wavelength range from 1500 nm – 1600 nm is demonstrated. The device based on photonic bandgap transmission, is electronically controlled and due to its compact configuration, can be easily incorporated into an optical network. A low insertion loss at zero attenuation state and a high extinction ratio of ~ 40 dB is obtained between the high and low transmission states of the attenuator. The device works on the application of a varying voltage applied …
A Fiber-Optic Voltage Sensor Based On Macrobending Structure, Pengfei Wang, Yuliya Semenova, Qiang Wu, Gerald Farrell
A Fiber-Optic Voltage Sensor Based On Macrobending Structure, Pengfei Wang, Yuliya Semenova, Qiang Wu, Gerald Farrell
Articles
Tempo Detection Using A Hybrid Multi-Band Approach, Mikel Gainza, Eugene Coyle
Tempo Detection Using A Hybrid Multi-Band Approach, Mikel Gainza, Eugene Coyle
Articles
In this paper, a novel tempo detection system is presented, which suggests the use of a hybrid multiband decomposition. The model tracks the periodicities of different signal property changes that manifest within different frequency bands by using the most appropriate onset/transient detectors for each frequency band. In addition, the proposed system applies a novel method to weight tempo candidates. Each contribution is evaluated by comparing the presented system against existing approaches using three different databases that comprises 1638 songs. These databases include the two publicly available database of songs used in the tempo evaluation contest of ISMIR 2004. These songs …
Lead Silicate Glass Microsphere Resonators With Absorption-Limited Q, Pengfei Wang, Genapathy Murugan, Timothy Lee, Xian Feng, Yuliya Semenova, Qiang Wu, Wei Loh, Gilberto Brambilla, James Wilkinson, Gerald Farrell
Lead Silicate Glass Microsphere Resonators With Absorption-Limited Q, Pengfei Wang, Genapathy Murugan, Timothy Lee, Xian Feng, Yuliya Semenova, Qiang Wu, Wei Loh, Gilberto Brambilla, James Wilkinson, Gerald Farrell
Articles
We report the fabrication and characterization of a lead-silicate glass microsphere resonator. We show that at the wavelengths near 1555 nm high Q modes can be efficiently excited from a 109 μm diameter lead-silicate glass microsphere via evanescent coupling using a tapered silica fiber with a waist diameter of 2 μm. Resonances with Q-factors as high as 0.9×107 were observed. This is very close to the theoretical material-limited Q-factor and is the highest Q-factor reported so far from a nonlinear glass microsphere.
Investigation Of Singlemode-Multimode-Singlemode And Singlemode-Tapered Multitmode-Singlemode Fibre Structures And Their Application For Refractive Index Sensing, Pengfei Wang, Gilberto Brambilla, Ming Ding, Yuliya Semenova, Qiang Wu, Gerald Farrell
Investigation Of Singlemode-Multimode-Singlemode And Singlemode-Tapered Multitmode-Singlemode Fibre Structures And Their Application For Refractive Index Sensing, Pengfei Wang, Gilberto Brambilla, Ming Ding, Yuliya Semenova, Qiang Wu, Gerald Farrell
Articles
All-fiber in-line single-mode–multimode–single-mode (SMS) and single-mode–tapered-multimode–single-mode (STMS) fiber structures are investigated. A wide-angle beam propagation method in cylindrical coordinates is developed and employed for numerical simulations of the light propagation performance of such fiber devices. The effect of strong mode interference on the performance of the devices is studied and verified numerically; results indicate that the proposed STMS structure can be exploited for measuring a broad refractive index range with reasonable high resolution, compared with the conventional SMS structure.
Parallel Operation Of Inverters And Active Power Filters In Distributed Generation System: A Review, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon
Parallel Operation Of Inverters And Active Power Filters In Distributed Generation System: A Review, Shafiuzzaman Khan Khadem, Malabika Basu, Michael Conlon
Articles
In this paper a technical review of parallel operation of power electronics inverters for load sharing conditions in distributed generation (DG) network is presented. Emphasis is given to parallel operation of Active Power Filters (APFs) as they are widely used to mitigate load current disturbances into DG networks. Discussions on recent advances in control strategies as applied to APFs are presented.
Dielectric And Optical Study Of Biaxial Bent-Core Nematic Liquid Crystal, S. P. Sreenilayam, M. Nagaraj, Yuri Panarin, J. K. Vij, C. Keith, C. Tschierske
Dielectric And Optical Study Of Biaxial Bent-Core Nematic Liquid Crystal, S. P. Sreenilayam, M. Nagaraj, Yuri Panarin, J. K. Vij, C. Keith, C. Tschierske
Articles
We report the observation of biaxial nematic phase in a bent-core molecular system in which the biaxiality exists on a microscopic scale using polarizing microscopy, electro-optics and dielectric spectroscopy. An application of electric field induces a macroscopic biaxiality and therefore electro-optic switching. The observed electro-optic switching is explained in terms of the interaction of the ferroelectric clusters with the electric field. Dielectric spectra of the sample shows existence of low-frequency collective processes related to the microscopic polar clusters. The dielectric constant changes its sign from positive to negative and again to positive values.
In-Silico Hyperthermia Performance Of A Near-Field Patch Antenna At Various Positions On A Human Body Model, Sergio Curto, Terrence See, Patrick Mcevoy, Max Ammann, Zhi Ning Chen
In-Silico Hyperthermia Performance Of A Near-Field Patch Antenna At Various Positions On A Human Body Model, Sergio Curto, Terrence See, Patrick Mcevoy, Max Ammann, Zhi Ning Chen
Articles
A compact patch applicator designed to enhance targeted energy coupling at 434 MHz is a key enabler for sensitizing temperature increments in body regions containing superficial tumours. A detailed FDTD body model is used to explore simulated RF coupling and temperature increments for typical clinical conditions. The antenna impedance matching, specific absorption rate and thermal distribution parameters are evaluated to identify applied performance outcomes. The analysis reveals physiological-RF coupling patterns for an optimised closely-coupled single element applicator.
The Synchronized Short-Time-Fourier-Transform: Properties And Definitions For Multichannel Source Separation., Ruairí De Fréin, Scott Rickard
The Synchronized Short-Time-Fourier-Transform: Properties And Definitions For Multichannel Source Separation., Ruairí De Fréin, Scott Rickard
Articles
This paper proposes the use of a synchronized linear transform, the synchronized short-time-Fourier-transform (sSTFT), for time-frequency analysis of anechoic mixtures. We address the short comings of the commonly used time-frequency linear transform in multichannel settings, namely the classical short-time-Fourier-transform (cSTFT). We propose a series of desirable properties for the linear transform used in a multichannel source separation scenario: stationary invertibility, relative delay, relative attenuation, and finally delay invariant relative windowed-disjoint orthogonality (DIRWDO). Multisensor source separation techniques which operate in the time-frequency domain, have an inherent error unless consideration is given to the multichannel properties proposed in this paper. The sSTFT …