Antenna

In this article, we will carry out the calculation for the power budget for a connection between a station of reception and a geostationary satellite, while stressing a phenomenon which influences the power budget which is the "phenomenon of antenna depointing" and that for both segments: ground and space. The application enables us to consider the losses caused by this phenomenon on the power budget and its impact on our connection while passing by the two cases: depointing of the antenna on the ground, and the depointing of the antenna on board. Finally, we will try to draw up a comparative study to see which of the two antennas can be most affected.

Keywords: MIMO antenna UWB antenna Model predictive Control Non-uniform microstrip line Printed monopole antenna a b s t r a c t A novel ultra wideband (UWB) printed monopole multiple-input multiple-output (MIMO) antenna with non-uniform transmission line using nonlinear model predictive control (NMPC) is presented. The proposed antenna is superior to conventional antennas in terms of dimensions, gain, and efficiency while maintaining the impedance bandwidth. In order to improve the results, a non-uniform transmission line has been used for impedance matching between the radiated patch element and the coaxial cable. For designing the non-uniform transmission line, it has been expanded using cosine terms. Regarding the presence of differential equation for the variation in the impedance of the transmission line and its transformation to the state-space equation, NMPC has been employed to design the transmission line and determine the cosine expansion coefficients. Two base antennas, as MIMO, were simulated configuration and fabricated. The surface area of the proposed MIMO antenna is 0.99 k 2 g , the wavelength has been obtained for the center frequency of the 3.16 GHz to 10.6 GHz range, and its mutual coupling, peak gain, channel capacity loss (CCL), total active reflection coefficient (TARC), mean effective gain (MEG) and diversity gain (DG), envelope correlation (ECC) are acceptable. The simulation and measurement results are in good agreement, and the proposed antenna is suitable for MIMO applications. Ó 2020 The ''Authors". Karabuk University. Publishing services by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

In this paper, a wideband log periodic dipole antenna (LPDA) with small size is proposed. The arms of the dipole are in the shape of a second order fractal, which makes each dipole element to resonate in more than one frequency. This results in a LPDA antenna whose size can be greatly reduced. The proposed antenna has a substrate size of 90 × 60 mm 2 and operates over 2-8 GHz bandwidth with VSWR< 2. The antenna has stable pattern over the frequency range.

A previous report of the discovery of exocrine glands in the antennal club of queens and workers of Solenopsis invicta Buren, 1972 left open the question of the extent to which similar glands occur in the Formicidae family. We wanted to know if these antennal glands are unique to Solenopsis, or they are found in a wider taxonomic group. Using scanning electron microscopy, we examined the antennae of 41 ant species. Presence of the antennal glands was indicated by a characteristic circumferential ring of pores in a distal antennal segment of workers. Pores were found in the 9th antennal segment of all 26 species of Solenopsis examined. Pores were absent in the following: Monomorium minimum, M. pharaonis, Pheidole sp., Crematogaster sp., Linepithema humile, Forelius sp., Dorymyrmex sp., Paratrechina sp., Oecophylla smaragdina, Campanotus sp., Ectatomma ruidum, E. tuberlatum, and Pseudomyrmex ferruginea. However, pores were found in the antennal club of Tetramorium bicarinatum workers and queens. After KOH digestion of T. bicarinatum antennae, internal canals were observed in both workers and queens, and the canals are connected to spherical reservoirs in queens. T. bicarinatum was the only non-Solenopsis species examined, which showed evidence for antennal glands in the distal funiculus. Microsc. Res. Tech., 2008. © 2008 Wiley-Liss, Inc.

— This paper is about study of various microstrip patch antennas designed for satellite communication applications using various performance improvement techniques. From the appearance of the satellite communication we need to improve two key aspects in the communication systems: The quality of the service (greater quality and bandwidth of the signal) as well as the costs (smaller investment for the operation and maintenance). One of the ways to improve these two aspects is the miniaturization of communication components using microstrip antenna. The objective of this paper is to compare various techniques of designing microstrip antenna for the purpose of satellite communications.

This paper discusses a new implementation of a Gaussian minimum-shift keying (GMSK) modulator and demodulator on the European Space Agency (ESA)'s common deep-space receiver-the Intermediate Frequency Modem System (IFMS), which is a software radio based platform. The GMSK demodulator is needed for ESA's deep-space and near-Earth missions, starting with the Herschel-Planck satellites in 2008. The implementation requirements and hardware restrictions from the IFMS lead to the need for a significant simplification versus the optimum demodulation approach. In part, this can be achieved by using a demodulator based on the Laurent decomposition, yet further simplifications and changes to obtain a feasible implementation were necessary. The presented GMSK demodulator was directly implemented on the existing IFMS receiver without requiring any hardware changes. Measurements with the demodulator showed only a marginal technical degradation in the order of 0.1-0.3 dB for the chosen approach. Furthermore, for testing purposes, a GMSK modulator was implemented on the same platform.

Теоретически и экспериментально проведено исследование согласования и характеристик излучения сверхширокополосных излучателей на основе ТЕМ рупора, в том числе новых типов, для кольцевых антенных решеток. Теоретические результаты получены путем электродинамического моделирования на основе метода конечных элементов и метода конечных разностей во временной области.

A micromachined 300-GHz slotted waveguide antenna is demonstrated using a simple fabrication technique based on metal-coated SU-8 thick resist. The antenna is designed to be built from a four-layer structure of equal layer thickness. It is fully characterized, and the measured radiation patterns show excellent agreement with the simulation. An H-plane matched right-angle bend is integrated in the antenna in order to achieve reliable and accurate connection with standard waveguide flange. The micromachined antenna is directional and low-profile and may find applications in low-cost sensors and radars.

In this study, a dual band compact antenna that can provide dual polarization for each band is proposed and its design is presented. Proposed structure operates at 0.96 GHz and 1.81 GHz frequencies. Thus the antenna can be used for GSM (Global System for Mobile Communications) applications. It consists of two symmetrical antennas that placed closely to obtain compact size. The distance (edge to edge) between these antennas is 10 mm ~ 0.032 λl , as the λl is the wavelength at the lower band of the operation. Isolation between the feeding ports in the structure has been succeeded with a slot on the ground plane, the length and width of the slot adjusts the isolation. In the two operation frequencies the isolation is below -10dB. The proposed MIMO (Multiple-Input Multiple-Output) antenna is simulated and then fabricated prototype is measured. The results of simulation and measurements are presented and the results are consistent with each other.

ABSTRACT This paper proposes a dual-band circular polarization (CP) monopole antenna. This antenna can generate a broadband impedance-bandwidth from 2.17 to 8.47 GHz, and excite a left-hand circular polarization (LHCP) at 2.48 GHz and right-hand circular polarization (RHCP) at 3.90 GHz. The measured 3-dB axial ratio (AR) bandwidths are about 140 MHz from 2.41 to 2.55 GHz approximately 5.6% with respect to the center frequency at 2.48 GHz and 900 MHz from 3.45 to 4.35 GHz approximately 23.1% with respect to the center frequency at 3.90 GHz.

Here, we introduce a new class of computer which does not use any circuit or logic gate. In fact, no program needs to be written: it learns by itself and writes its own program to solve a problem. Godels incompleteness argument is explored here to devise an engine where an astronomically large number of IfThen arguments are allowed to grow by self assembly, based on the basic set of arguments written in the system, thus, we explore the beyond Turing path of computing but following a fundamentally different route adopted in the last half a century old non Turing adventures. Our hardware is a multilayered seed structure. If we open the largest seed, which is the final hardware, we find several computing seed structures inside, if we take any of them and open, there are several computing seeds inside. We design and synthesize the smallest seed, the entire multilayered architecture grows by itself. The electromagnetic resonance band of each seed looks similar, but the seeds of any layer...

This paper proposes a design of 0.15μm Monolithic Microwave Integrated Circuit (MMIC) power amplifier using GaAs pHEMT technology at 2.4 GHz which employs feed forward linearization technique to improve linearity. The amplifier is designed to operate in personal communication systems (PCS) frequency range using WIN semiconductor GaAs pHEMT technology. Single stage power amplifier is designed in lumped and distributed components with its layout. Linearity of PA is improved by Feed forward Linearization technique. To evaluate the performance of proposed linearized amplifier, Advanced Design system (ADS) tool is used. The designed circuit results with 13.65dBm output power at 1dB compression point (P1dB), 6dB power gain and maximum Power added efficiency of 16.4%. Linearity achieved by feed forward linearizer circuit with third order intermodulation suppression of 30dBc for the output power level of 8.217dBm and 1dB compression point at an input power of 15 dBm whereas 6 dBm for the Power amplifier without feed forward linearizer circuit. The designed Power amplifier system with feed forward linearizer had IMD3 suppression of 30dBc which is in appreciable range with improvement in 1dB compression point.

International Journal of Microwave Engineering (JMICRO) is a peer-reviewed, open access journal which invites high quality manuscripts that focuses on Engineering and theory associated with microwave / millimeter-wave technology, guided wave structures, electromagnetic theory and implementation. Authors are invited to submit original research works that stimulate the development of latest technology in industry and academia. Good quality review papers and short communications are also acceptable. Research areas suitable for publication include, but are not limited to the following fields:

In this paper, a printed monopole antenna with reduced ground plane has been
presented as a candidate for use in ultra-wideband applications. The monopole antenna structure
is a nearly square shaped with m-slot embedded in it. A 50­ microstrip line is used to feed the
proposed antenna. The proposed antenna has been supposed to be etched using a substrate with
relative permittivity of 4.6 and thickness of 1.6 mm. Modeling and performance evaluation of
the proposed antenna have been carried out using a method of moments based EM simulator,
IE3D. Results show that the proposed antenna has a compact size of 20mm £ 25 mm. The
resulting antenna has been found to possess an impedance bandwidth, for voltage standing-
wave ratio less than 2, covering the required impedance bandwidth for UWB applications with
5/6 GHz band notch characteristics. Simulation results show that the lower frequency is primarily
determined by the monopole radiating element perimeter, while the slot has an e®ective role to
allocate the position of the band notch. A parametric study has been conducted to provide more
understanding of the e®ects of antenna parameters on its performance. Besides the reasonable
performance, the simple structure of the proposed antenna will make it an attractive choice for
the antenna designers.

Abstract— Planar Inverted F Antenna or PIFA is the type of antenna with small dimensions, light weight, and low manufacturing cost, so it is suitable to be applied in communication devices which has relatively small dimension. PIFA is composed of groundplane, radiating element, a wire that connected to the groundplane and radiating element, and a shorting pin that connects the groundplane with the top plate. PIFA can be designed to work on multiple frequencies (multiband frequencies) by adding slots on its patch. In this research, PIFA antennas with U-slot and L-slot form are designed which can work at 1800 MHz and 2300 MHz (GSM and LTE). The antenna characteristics will be compared so that can be used as a recommendation to select suitable PIFA antennas.
Abstrak— Planar Inverted F Antenna atau PIFA adalah jenis antena dengan dimensi yang kecil, bobot yang ringan, dan biaya pembuatan yang relatif murah sehingga sangat cocok untuk diaplikasikan pada perangkat-perangkat komunikasi yang ukurannya relatif kecil. PIFA tersusun atas groundplane, elemen peradiasi, kawat catuan yang tersambung dengan groundplane dan elemen peradiasi, serta shorting pin yang menghubungkan groundplane dengan top plate. PIFA dapat dirancang agar dapat bekerja pada beberapa frekuensi (multiband frequency) dengan  menambahkan slot pada bagian patch-nya. Dalam penelitian ini, dirancang dan direalisasikan antena PIFA dengan bentuk U-slot dan L-slot yang bekerja pada frekuensi 1800 MHz dan 2300 MHz (GSM dan LTE). Kedua prototipe antena yang dihasilkan akan dibandingkan karakteristiknya sehingga dapat digunakan sebagai rekomendasi pemilihan jenis antena PIFA untuk aplikasi terkait.

A novel design of monopole antenna with trapezoidal configuration is presented for WLAN application. The proposed antenna provides dual-band circularly polarized at 2.4 and 5.3 GHz frequencies with 6.25% and 2.83% bandwidth, respectively. The antenna is fed through a microstrip feed line and is backed by a finite ground plane with two tuning stubs. The circular polarization for the proposed dual-band antenna is demonstrated by 3dB axial ratio (AR) spectrum. Simulation results are provided by using two full wave software packages, Ansoft HFSS and CST microwave studio and the results are compared with each other.

Wide band Array Antenna operates in Ku-band (10.7-12.7 GHz) frequency composed of N×N radiating elements. This antenna aims at the reception of television satellite signals. The goal of this research is to provide better possibility of electronic beam control instead of manual or mechanical control, and design compact and low cost phase shifters to be inserted in the feeding network of this antenna.

The electronic control of the phase shifter will allow the control of beam steering. The emphasis of this project will be done at the beginning on the design of a good phase shifter in Ku band. The aim of this research is to define, simulate, release and measure a continuous phase shifter. Better reflection loss, low transmission loss, low Cost of array antennas, large range of phase-shifter, phase flatness and bandwidth will be achieved by providing better gain.

Keywords —ADS (Advanced Design System) Software, KU Band Antenna Array, Schiffman Phase Shifters, Beam Switching Antenna, Varactor Diode (MA46H120).

A small-size CPW-feed multi-band planar monopole antenna is presented. A Swallow-Shaped-Patch (SSP) that covers the Ultra-Wideband (UWB) frequency range is used in the proposed design. To create a multi-band antenna, several narrow pentagon slots, acting as resonance paths, can be integrated with the SSP antenna. Triple-band antennas are simulated and good results are obtained, while showing a very sharp band-rejection performance at 3.92 GHz, 5.34 GHz and 5.88 GHz, respectively. The antennas have omnidirectional and stable radiation patterns across all the relevant bands. Moreover, a prototype of the triple-band antenna is fabricated and measurement results are compared with simulation results.

This paper presents design of antenna for dual band frequencies. (2.3 GHz and 5.2 GHz). Comparative analysis is presented on the basis of geometry of patch of antenna. Rectangular, Circular and Triangular Patch is used to compare the results. Inset feed is used due to which proposed CPW antenna achieves size reduction, compactness, good impedance matching and wide bandwidth at the fundamental operating frequency. Vias can be eliminated in case of CPW technology because it offers ground at the same layer. Antenna is designed for 2.6 GHz. For enhancing the bandwidth and performance DGS is introduced. Defected Ground Structure (DGS) can be used as an unique approach to improve the performance of the microstrip patch antennas specially the resonating frequency. High Frequency Structure simulator is used to analyse the design.