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1

Study on Metamaterial-based Bio-inspired Microstrip Antenna Array for 5G Enabled Mobile Health Technology

Colaco John, Cotta Jillian

International Journal of Electronics and Telecommunications

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2022

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Vol. 68, No. 2

201--207

EN

5G is a fifth-generation wireless technology that enables extremely fast data transfers and massive connection capacity. Existing Mobile health technology requires more reliable connection power and data transfer rates. The purpose of this research is to design, analyse, and compare the performance of a bio-inspired lotus-shaped microstrip patch antenna array with two to three radiating elements. The proposed antenna utilizes proximity coupled indirect microstrip transmission line feeding technique operating in the 24 GHz-30 GHz frequency band. The results indicate that performance continues to improve as the number of radiating elements increases. Moreover, each radiating element is loaded with complementary and non-complementary split-ring resonators (SRRs). The performance of the proposed microstrip antenna array is then analysed and compared with and without split-ring resonators. The findings validate that the proposed bio-inspired metamaterial-based microstrip patch array antenna is more reliable and performs better than an antenna without SRRs.

2

Design and Simulation of 2× 2Micro Strip Circular Patch Antenna Array at 28 GHz for 5G Mobile Station Application

Hasan Salim Abdullah, Ahmed Abdulsattar Mohamed, Abdulqader Mohanad Nawfal, Dawood Younis Shareef

International Journal of Electronics and Telecommunications

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2022

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Vol. 68. No. 4

721-–729

EN

This paper proposes the design and simulation of 2×2 circular patch antenna array working at 28 GHz by using four inset feed micro strip circular patch antennas to achieve beam forming with directivity around 13dB which is required to overcome part of high path loss challenge for high data rate mm-5G mobile station application. Four element 2x2 array consists of two 1x2 circular patch antenna arrays based on power divider and quarter wavelength transition lines as a matching circuit. The designed antenna array is simulated on RT/duroid 5880 dielectric substrate with properties of 0.5mm thickness, dielectric constant ε r =2.2, and tangent loss of 0.0009 by using Computer System Technology (CST) software. The performances in terms of return loss, 3D–radiation pattern is evaluated at 28 GHz frequency band. The design also includes the possibility of inserting four identical 2x2 antenna arrays at four edges of mobile station substrate to achieve broad space coverage by steering the beams of the mobile station arrays.

3

Bandwidth enhancement of array microstrip antenna using spiral stub For 5G communication system

Alam Syah, Surjati Indra, Sari Lydia, Anindito Atria, Putranto Agam Yudi, Firmansyah Teguh

Przegląd Elektrotechniczny

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2021

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R. 97, nr 11

40--44

EN

This paper proposes a new design of a 2x2 microstrip array antenna with spiral stub for a 5G communication system at the resonant frequency of 3.5 GHz. Spiral stub is useful for increasing the bandwidth value of the proposed antenna. The spiral stub is designed using a microstrip line with an impedance of 70.7 ohms. This study proposes three antenna models by adjusting the number and dimensions of the spiral stubs. From the simulation results using EM Simulation, the optimal bandwidth is obtained when the number of spiral stubs (n) = 3 with dimensions of spiral stub Wstub =18.5 mm and Ls = 8 mm . The bandwidth of the proposed antenna is 0.8 GHz or an increase until 88.88% compared with array 2x2 without spiral stubs. Furthermore, the gain of the proposed antenna is 10.67 dB at the resonant frequency of 3.5 GHz. This research is very useful for increasing bandwidth for the purposes of 5G communication systems.

PL

W artykule zaproponowano nowy projekt anteny mikropaskowej 2x2 ze spiralnym odgałęzieniem dla systemu komunikacji 5G na częstotliwości rezonansowej 3,5 GHz. Spiralny odcinek jest przydatny do zwiększania wartości szerokości pasma proponowanej anteny. Spiralny króciec został zaprojektowany z wykorzystaniem linii mikropaskowej o impedancji 70,7 omów. W niniejszym opracowaniu zaproponowano trzy modele anten, dostosowując liczbę i wymiary końcówek spiralnych. Z wyników symulacji z wykorzystaniem symulacji EM optymalną szerokość pasma uzyskuje się, gdy liczba króćców spiralnych (n) = 3 o wymiarach króćca spiralnego Wstub =18,5 mm i Ls = 8 mm . Przepustowość proponowanej anteny wynosi 0,8 GHz lub jest wyższa o 88,88% w porównaniu z macierzą 2x2 bez spiralnych odgałęzień. Ponadto zysk proponowanej anteny wynosi 10,67 dB przy częstotliwości rezonansowej 3,5 GHz. Badania te są bardzo przydatne do zwiększania przepustowości na potrzeby systemów komunikacji 5G.

4

Optimized Driver Placement for Array-Driven Flat-Panel Loudspeakers

Anderson D. A., Heilemann M. C., Bocko M. F.

Archives of Acoustics

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2017

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Vol. 42, No. 1

93--104

EN

The recently demonstrated ‘modal crossover network’ method for flat panel loudspeaker tuning employs an array of force drivers to selectively excite one or more panel bending modes from a spectrum of panel bending modes. A regularly spaced grid of drivers is a logical configuration for a two-dimensional driver array, and although this can be effective for exciting multiple panel modes it will not necessarily exhibit strong coupling to all of the modes within a given band of frequencies. In this paper a method is described to find optimal force driver array layouts to enable control of all the panel bending modes within a given frequency band. The optimization is carried out both for dynamic force actuators, treated as point forces, and for piezoelectric patch actuators. The optimized array layouts achieve similar maximum mode coupling efficiencies in comparison with regularly spaced driver arrays; however, in the optimized arrays all of the modes within a specified frequency band may be independently addressed, which is important for achieving a desired loudspeaker frequency response. Experiments on flat panel loudspeakers with optimized force actuator array layouts show that each of the panel modes within a selected frequency band may be addressed independently and that the inter-modal crosstalk is typically −30 dB or less with non-ideal drivers.

5

Shear Wave Velocity Estimates through Combined Use of Passive Techniques in a Tectonically Active Area

Biswas R., Baruah S.

Acta Geophysica

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2016

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Vol. 64, no. 6

2051--2076

EN

We made an attempt to assess the shear wave velocity values VS and, to a lesser extent, the VP values from ambient noise recordings in an array configuration. Five array sites were situated in the close proximity to borehole sites. Shear wave velocity profiles were modeled at these five array sites with the aid of two computational techniques, viz. spatial autocorrelation (SPAC) and H/V ellipticity. Out of these five array sites, velocity estimates could be reliably inferred at three locations. The shear wave velocities estimated by these methods are found to be quite consistent with each other. The computed VS values up to 30 m depth are in the range from 275 to 375 m/s in most of the sites, which implies prevalence of a low velocity zone at some pocket areas. The results were corroborated by evidence of site geology as well as geotechnical information.

6

Simple Linear Comparison of Strings in V -order

Alatabbi A., Daykin J. W., Rahman M. S., Smyth W. F.

Fundamenta Informaticae

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2015

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Vol. 139, nr 2

115--126

EN

In this paper we focus on a total (but non-lexicographic) ordering of strings called V - order. We devise a new linear-time algorithm for computing the V -comparison of two finite strings. In comparison with the previous algorithm in the literature, our algorithm is both conceptually simpler, based on recording letter positions in increasing order, and more straightforward to implement, requiring only linked lists.