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Development of Microstrip Patch Antenna Design for GPS in Myanmar
Zin Mar Phyo,
Tint May Nway,
Khin Kyu Kyu Win,
Hla Myo Tun
Issue:
Volume 8, Issue 1, June 2020
Pages:
1-11
Received:
14 January 2020
Accepted:
27 January 2020
Published:
10 February 2020
Abstract: Polarization matching between the transmitter and receivers is an important thing due to the signal losses and multipath fading. In GPS application, L1 Band is commonly used to find the location all over the world. In this research, edge-truncated circularly polarized microstrip patch antenna and slot-loaded circularly polarized microstrip patch antenna are presented. The first design is diagonally fed with a single coaxial probe and the upper edges are truncated to reduce the patch size. This design provides the bandwidth of 79.5 MHz with the axial ratio bandwidth of 26 M Hz. In the second design, the slots are loaded to the patch in order to reduce patch size. The single coaxial diagonal feed is also applied to the patch. This design achieves the bandwidth of 56 MHz and the axial ratio bandwidth is about 22 M Hz. The second design can also provide the size reduction of 18.16%. However, the gain of the second antenna decreases to 3 dB due to its reduced size. As these simulated results, these two designs can be used in L1 Band GPS application. And then, these antenna designs are fabricated and measured the results such as return loss and axial ratio. The characteristics of these fabricated antennas are also applicable for the targeted application.
Abstract: Polarization matching between the transmitter and receivers is an important thing due to the signal losses and multipath fading. In GPS application, L1 Band is commonly used to find the location all over the world. In this research, edge-truncated circularly polarized microstrip patch antenna and slot-loaded circularly polarized microstrip patch an...
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Compact Stellar Model with Two Different Equations of State
Daddy Balondo Iyela,
Nestor Anzola Kibamba
Issue:
Volume 8, Issue 1, June 2020
Pages:
12-17
Received:
5 June 2019
Accepted:
15 August 2019
Published:
25 February 2020
Abstract: We have modelled a neutral non-homogeneous anisotropic stellar compact object with two distinct equations of state in general relativity framework. We have considered the macroscopic features of a general relativistic gravitating compact object. The equation of state is quadratic in the core and linear in the envelope. There is smooth matching between the core, envelope and the vacuum exterior regions. We found the masses, radii and compactness of some compact objects such PSR J1614-2230, PSR J1903+0327, Vela X-1, SMC-X-1, Cen X-3; which are in agreement with previous investigations. The gravitational potentials and the matter variables are well behaved throughout the stellar structure. We present in particular the variation of the radius in the core and the envelope of the star by changing some parameters values. Physical features of the pulsars PSR J1614-2230 are presented in more details. It observed that the radial pressure in the core is higher than the radial pressure in the envelope. The investigation reveals that the model is physically relevant for the study of observed compact stars.
Abstract: We have modelled a neutral non-homogeneous anisotropic stellar compact object with two distinct equations of state in general relativity framework. We have considered the macroscopic features of a general relativistic gravitating compact object. The equation of state is quadratic in the core and linear in the envelope. There is smooth matching betw...
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Compact MMW-band Planar Diffraction Type Antennas for Various Applications
Yuriy Sydorenko,
Sergiy Provalov,
Sergiy Shylo,
Dana Wheeler
Issue:
Volume 8, Issue 1, June 2020
Pages:
18-27
Received:
5 February 2020
Accepted:
19 February 2020
Published:
28 February 2020
Abstract: The principles of formation of antennas of diffraction radiation with flat surface in the millimeter wave radio band are considered. Such kinds of antennas are based on the effect of the conversion of volumetric electromagnetic waves into surface waves of a dielectric waveguide in an open electrodynamic structure. A brief description of the theoretical basis for the calculations and examples of the technical implementation of flat (2D) antennas of diffraction radiation in the W-band and Ka-band are presented; their parameters and areas of possible use are discussed. In the E-plane angle-to-frequency dependence of beam position is realized with coefficient near 0,9/1% of frequency change. That makes it possible effective control of beam position in space (beam scanning along 1, or even along 2 axes). There was estimated that total active loss in such kind antennas is related to dielectric losses in the material of planar dielectric waveguide and to active losses at the elements of internal waveguide transitions in the ratio near (2: 1). Losses of first kind may be reduced due to implementation of novel dielectric materials providing the smallest dielectric loss (near as for the PTFE material) and appropriate mechanical rigidity at the same time. Active losses of the second kind may be reduced due to implementation of transitions on the base of super-size waveguides.
Abstract: The principles of formation of antennas of diffraction radiation with flat surface in the millimeter wave radio band are considered. Such kinds of antennas are based on the effect of the conversion of volumetric electromagnetic waves into surface waves of a dielectric waveguide in an open electrodynamic structure. A brief description of the theoret...
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Design and Fabrication of a Planar Inverted-F Antenna (PIFA) for LEO Satellite Application
Zin Thu Thu Lin,
Hla Myo Tun
Issue:
Volume 8, Issue 1, June 2020
Pages:
28-32
Received:
7 April 2020
Accepted:
22 April 2020
Published:
28 April 2020
Abstract: The paper is mainly emphasizes on the microstrip patch antenna design for satellite applications. The specific objective of this study is to solve the research problem on finding the simple and compact design for small satellite application in real world. A new design of a Planar Inverted-F Antenna (PIFA) with the two height of 12mm and 10mm are proposed for low Earth orbit (LEO) applications in S band. The antenna is a single form antenna with the coaxial probe fed is used. CST Microwave Studio student version was used for the simulation of the antenna and matching design parameters. The antennas are obtained an efficient high return loss -18.426dB and -18.169dB at S11, the return loss bandwidth of 471MHz and 466MHz. The radiation pattern results are analyzed beam width angle 85.1° and 95.1°. Moreover, the peak directivity gain results 4.7dBi and 4.79dBi, the absolute E-filed radiation effect are also presented. The actual measurement results for S11 parameter of return loss -13.54dB and -14.2dB, return loss bandwidth of 510MHz and 425MHz are also fabricated with the comparison of simulation and fabrication process of PIFA antenna characteristics. The measurement of the return loss (S11) and return loss bandwidth were almost identical with the simulation.
Abstract: The paper is mainly emphasizes on the microstrip patch antenna design for satellite applications. The specific objective of this study is to solve the research problem on finding the simple and compact design for small satellite application in real world. A new design of a Planar Inverted-F Antenna (PIFA) with the two height of 12mm and 10mm are pr...
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