iosr-JECE   Volume-16 ~ Issue-6 ~ Nov.-Dec. 2021

Abstract: This article presents rectangular microstrip antennas in modified fractal geometries. The modified fractal antennas are designed using the HFSS, which is based on the finite element method of computational electromagnetics. Three forms of the designed antennas is discussed and the various electrical parameters such as reflection coefficient, 2 D radiation pattern and 3 D radiation pattern are investigated. The designed antennas have various wireless applications such as 1.8 GHz GSM and 2.4 GHz WLAN and IEEE 802.11(a, b ,g and n).The designed antennas also have wideband behavior with the multiband applications.

Keywords: Micro strip patch antenna, Fractal, WLAN

[1]. Garg, R., P. Bhartia, I. Bahl, and A. Ittipiboon, Microstrip Antenna Design Handbook, Artech House.
[2]. Constantine A. Blanis, Antenna Theory Analysis and Design Third Edition wiley India 2005.
[3]. Zhang, Y. P. and J. J. Wang, "Theory and analysis of differentially-driven microstrip antennas," IEEE Trans. Antennas Propag., Vol. 54, 1092-1099, 2006.
[4]. Pozar, D. M. and D. H. Schaubert, Microstrip Antennas, the Analysis and Design of Microstrip Antennas and Arrays, IEEE Press, New York, 1995.
[5]. H Sabri and Z Atlasbaf "Two novel compact triple band microstrip annular ring slot antenna for PCS-1900 and WLAN application". PIERS letters vol 5,87-98, 2008.

Abstract: Electrocardiogram (ECG)is a non-invasive technique used mainly as a primary diagnostic tool for cardiovascular diseases. A pure ECG signal provides valuable information about the electrophysiology of heart diseases and the occurrence of ischemic changes. It provides necessary information about the functional aspects of the heart and cardiovascular system. The objective of this report is to automatically detect the cardiac problems in ECG signal. Recently developed digital signal processing technique is used in this report for the detection of cardiac problems. Hence this report develops a method for analysis of heartbeats to detect cardiac abnormalities in ECG signals. ECG generated waveforms are used to find patterns of irregularities in cardiac cycles in patients. In many cases, irregularities evolve over an extended period of time that requires continuous monitoring. However, this requires compression of ECG signals. The practical importance of ECG data compression has become evident in many aspects of computerized electrocardiography. Various ECG compression methods are discussed.

Keywords: Ambiguity domain, Ramanujan Fourier Transform, Ramanujan sums, Time-frequency, T wave alternanace.

[1]. Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology, "`Heart rate variability: Standards of measurement, physiological interpretation, and clinical use,"' Eur. Heart J., vol. 17, pp. 354-381, 1996
[2]. M. Teich, S. Lowen, K. Vibe-Rheymer, and C. Heneghan, "`Heart rate variability: measures and models, in Nonlinear Biomedical Signal Processing", vol. II, Dynamic Analysis and Modelling. New York: IEEE Press, 2001, pp. 159-213.
[3]. G. Berntson, J. Bigger, D. Eckberg, P. Grossman, P. Kaufmann,M.Malik,H. Nagaraja, S. Porges, J. Saul, P. Stone, and M. vander Molen, "Heart rate variability: Origins, methods, and interpretive caveats, "Psychophysiology, vol. 34, no. 6, pp. 623{648, Nov. 1997.
[4]. F. Mormann, R. G. Andrzejak, C. E. Elger, and K. Lenhn-ertz, "Seizure prediction: the long and winding road," Brain, vol. 130, no. 2, pp. 313-333, 2006.
[5]. R. Silipo, G. Deco, R. Vergassola, and C. Gremigni, "A characterization of HRVs nonlinear hidden dynamics by means of Markovmodels,"IEEE Trans. Biomed. Eng., vol. 46, no. 8, pp. 978-986, Aug. 1999.

Abstract: The use of single wideband antenna which covers wide range frequencies is very desirable for many applications including wireless and high data rate communications, imaging and sensing, position and tracking and radar. Here the realization of the planar monopole antenna which can works at different frequencies with good radiation was presented. The design a broadband monopole planar rectangular antenna that is printed on printed circuit board (PCB) consisted of a rectangular patch and a ground plane. Besides mathematical procedure, the step in designing this antenna needed a simulation to get more accurate hypothesis before realizing the antenna. In this study, researcher applied Matlab that can be used for designing and simulating the antenna in more detail and....

Keywords: Broadband Rectangular Planar Monopole Antenna, Planar Monopole Antenna, Matlab

[1]. Ahmad and Jar'alla, "Design and Simulation of Broadband Rectangular Microstrip Antenna". Eng. Tech Vol. 26 No.1, 2008s.
[2]. Azari. A and Rowhani. J, "Ultra Wideband Fractal Microstrip Antenna Design" , Electromagnetic Reseach C , Vol 2,2008, P. 7-12
[3]. Azim, Tariqul and Misran, "Compact Planar Antenna for UWB Applications", International Review of Electrical Engineering 5 (4) , pp. 1848-1852, 2010.
[4]. Balanis, C.A, "Antenna Theory: Analysis and Design", John Wiley and Son, New Jersey, 2005.
[5]. Dubost &Zizter, "Antennas a Large Band", Masson, Paris, 1976, P. 128-129.