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K. K. Ghosh

Bio: K. K. Ghosh is an academic researcher. The author has contributed to research in topics: Light-emitting diode & Photonic crystal. The author has an hindex of 4, co-authored 10 publications receiving 52 citations.

Papers
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Journal ArticleDOI
TL;DR: In this article, a 1D binary periodic structure with defect was analyzed using Transfer Matrix Method (TM) and FDTD simulation, and it was shown that the field is localised within the defect for the passband frequency.

28 citations

Journal ArticleDOI
TL;DR: In this paper, a two-dimensional triangular/hexagonal lattice silicon photonic crystal (Si) arrangement with hexagonal unit cells and two micromachined silicon cantilever tips is proposed for optical sensing of pressure.

13 citations

Proceedings ArticleDOI
18 May 2012
TL;DR: A comparative study on the choice of some of the conventionally used wavelets and their corresponding accuracies for ECG feature extraction by R peak detection and the B Spline wavelet transform of ECG signal is found to be the most efficient means ofECG signal processing.
Abstract: Fourier expansion, an excellent spectral decomposer of a signal suffers from a setback in its inability to represent the signal simultaneously in both time and spectral domain. ECG, a non-invasive recording method of bioelectric signal originated in the heart, provides valuable information about the electrical activity of human heart. Different features of the ECG can be extracted from the intervals and amplitudes of these waves at different sections. The primordial step in ECG feature extraction is the QRS Complex detection. The accuracy of the QRS complex detection defines the accuracy of locating all other waves and their intervals. The DWT, however a powerful tool for ECG feature extraction, is still limited by the choice of wavelets for use in feature extraction. We present a comparative study on the choice of some of the conventionally used wavelets and their corresponding accuracies for ECG feature extraction by R peak detection. In extracting, the B Spline wavelet transform of ECG signal is found to be the most efficient means of ECG signal processing.

12 citations

Journal ArticleDOI
TL;DR: From the analysis, it is found that the patterned film is suitable for near-infrared LED and the optimized structure, which gives maximum improvement at around 1.040 μm wavelength, is determined and fabricated using soft lithography.
Abstract: Analysis has been done of improvement of forward directional light extraction efficiency of light emitting diodes (LEDs) by surface patterning of different types of one-dimensional profiles on indium-zinc-oxide films developed recently by our group using sol–gel technique. Finite-difference time-domain simulations by MEEP software have been used for this purpose. From the analysis, it is found that the patterned film is suitable for near-infrared LED. The optimized structure, which gives maximum improvement at around 1.040 μm wavelength, is determined and fabricated using soft lithography. Further enhancement of the light output of the LED with the fabricated gratings is possible by introducing an interlayer within the top contact layer. The mathematical formulation of the coupling of light in structured/multilayered surfaces is also discussed.

6 citations

Journal ArticleDOI
TL;DR: In this paper, a photonic crystal (PhC) based structure is proposed for efficient splitting of light from broadband Light Emitting Diode (LED) into multiple narrowband sources.
Abstract: In this work, design of a photonic crystal (PhC) based structure is proposed for efficient splitting of light from broadband Light Emitting Diode (LED) into multiple narrowband sources. InP based transverse junction LED is considered. A vertical stack of two-dimensional (2D) square lattice PhC made up of GaAs/air is placed on top of this LED. 2D periodicity of the PhC is in the vertical plane of the top surface of the LED. On removal of a few GaAs rods the broadband light is focussed by effect of superlensing on the resulting T-type channel. The simulated result is studied by creation of curved air hole on the superlensing PhC. Only TM polarized light of specific wavelength ranges from the LED source is considered for narrowbands splitting as the TE polarized light does not have suitable bandgap there.

3 citations


Cited by
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Journal ArticleDOI
TL;DR: An improved integer IIR filter for portable ECG monitors is presented and can instantaneously and effectively eliminate baseline drift of main interference frequency band and 50-Hz power frequency interference in ECG signal.
Abstract: Electrocardiogram (ECG) signal is a direct and effective way to find cardiovascular disease timely, which can intuitively reflect changes of the heart beat and activities of different parts Due to the noise interference from surroundings, acquisition of real-time and high-quality ECG signal is a big challenge for portable mobile medical systems Integer coefficients infinite impulse response (IIR) digital filter is suitable for portable mobile platform, but it will be a little bit of distortion So, an improved integer IIR filter for portable ECG monitors is presented in this paper The proposed IIR filter can instantaneously and effectively eliminate baseline drift of main interference frequency band and 50-Hz power frequency interference in ECG signal The method is verified by a specific example and MIT/BIH Arrhythmia Database The improved integer coefficients IIR filter was applied in a portable mobile medical system It can meet the requirements of ECG filtering in real-time and filtering performance

55 citations

Journal ArticleDOI
TL;DR: In this paper, the optical properties of a one-dimensional defected photonic crystal structure (1DDPC) were investigated theoretically by using the transfer matrix method (TMM).
Abstract: In the present work, we have investigated theoretically the optical properties of a new one-dimensional defected photonic crystal structure (1DDPC). The structure is composed of alternating layers of metamaterial (double-negative material) and high Tc superconductor material called Hg1223 defected with a dielectric material (SiO2) at the center of the structure. The transmittance spectra of the proposed structure are obtained by using the transfer matrix method (TMM). We noticed that multiple transmittance peaks within the photonic band gap (PBG) as the thickness of defect layer increases. The tunable filtering feature is obtained by varying the thicknesses of metamaterial and superconductor layer. In addition, the defect peak is red shifted as well as photonic band gap tuned to low-frequency region. Our structure is sensitive to the variation of the angle incidence. Also, defect mode shown to be blue shifted as the angle of incidence increases. The tunable filtering properties are very useful in the optoelectronic applications.

52 citations

Journal ArticleDOI
TL;DR: Light is shed on the different methods existing in the research domain literature that are intended to be used in ectopic beats detection and correction and the effect of ectopic beat correction methods on the HRV signal parameters is highlighted.

42 citations

Journal ArticleDOI
01 Feb 2021-Optik
TL;DR: In this article, a novel microcantilever sensor for early detection of cancer in human body using an integrated optical micro ring resonator is presented. But, the authors did not consider the effect of geometrical modification of microcants on sensitivity and quality factor of proposed sensor.

16 citations

Journal ArticleDOI
TL;DR: In this paper, the authors theoretically investigated the near infrared filtering properties in a transmission narrowband filter with defective photonic crystal of (LH) N D(HL) N,w hereN is the stack number, L is SiO2, H is InP, and defect layer D is an extrinsic semiconductor of n-type silicon (n-Si).
Abstract: In this work, near infrared filtering properties in a transmission narrowband filter are theoretically investigated. The filter is a defective photonic crystal of (LH) N D(HL) N ,w hereN is the stack number, L is SiO2, H is InP, and defect layer D is an extrinsic semiconductor of n-type silicon (n-Si). It is found that there are multiple transmission peaks within the photonic band gap (PBG) as the defect thickness increases. The filtering position can be changed by varying the doping density in n-Si. That is, the peak (channel) wavelength is blued-shifted when the doping density increases. In the angle-dependent filtering property, the channel wavelength is also blued-shifted as the angle of incidence increases for both TE and TM waves. These filtering properties are of technical use in the applications of semiconductor optoelectronics.

15 citations