scholarly journals Design of Tunable Monopole Arm Planar Spiral Antenna for Cognitive Radio

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Rahul Yadav
Keyword(s):  
Cognitive Radio ◽  
Frequency Tuning ◽  
Impedance Matching ◽  
Ground Plane ◽  
Excitation Frequency ◽  
Antenna Design ◽  
Frequency Range ◽  
Spiral Antenna ◽  
Front End ◽  
Quarter Wavelength

This paper presents a spiral antenna design operating in the frequency range of 1–15 GHz having both selective notch bands and wideband response. The main feed arm of spiral antenna is configured as rectangular monopole of width quarter wavelength to achieve impedance matching with standard 50 Ω excitation. Frequency tuning in the design is achieved by placing varactor diode at an appropriate position along the spiral arms and in the ground plane. The design offers a peak gain of 3.4 dB (simulated) and 3 dB (measured). The unique frequency response of antenna makes its suitable to be used for front-end system of cognitive radio for sensing the spectrum in various modes.

Quasi-self-complementary ultra-wideband antenna with band rejection characteristics

2018 ◽  
Vol 10 (3) ◽  
pp. 336-344 ◽  
Author(s):  
Rajarshi Sanyal ◽  
Partha Pratim Sarkar ◽  
Santosh Kumar Chowdhury
Keyword(s):  
Impedance Matching ◽  
Ground Plane ◽  
Equivalent Circuit Model ◽  
Ultra Wideband ◽  
Antenna Design ◽  
Impedance Bandwidth ◽  
Novel Structure ◽  
Quarter Wavelength ◽  
Matching Element ◽  
Rejection Band

This article presents a compact novel quasi-self-complementary semi-octagonal-shaped antenna for ultra-wideband (UWB) application. The proposed novel structure is fed by a microstrip line where different rectangular truncation is etched to the ground plane as an impedance matching element, which results for much wider impedance bandwidth (VSWR<2) from 2.9 to 20 GHz. In order to obtain band-notched characteristics at 5.5 GHz, an open-ended, quarter wavelength, spiral-shaped stub is introduced in the vicinity of the truncated part of the ground plane. An equivalent circuit model is adopted to investigate the band rejection characteristics of the ground plane stub. Sharpness of the rejection band can be controlled by maintaining the gap between stub resonator and the slotted periphery of ground plane. The proposed antenna design is validated by experimental measurements.

Performance Evaluation of SDR Blade RF using Wide-band Monopole Antenna for Spectrum Sensing Applications

2021 ◽  
Vol 36 (4) ◽  
pp. 419-424
Author(s):  
Ahmed Ibrahim ◽  
Wael Ali ◽  
Hassan Aboushady
Keyword(s):  
Performance Evaluation ◽  
Cognitive Radio ◽  
Spectrum Sensing ◽  
Software Defined Radio ◽  
Ground Plane ◽  
Wide Band ◽  
Monopole Antenna ◽  
Antenna Design ◽  
Wireless Technologies ◽  
Sensing Applications

A spectrum-sensing algorithm is used to detect the available and the occupied frequency bands. The wideband antenna design approach is used for a microstrip fed monopole antenna that can be used for various wireless technologies such as GSM, UMTS, LTE, and WiFi operating at different frequencies from 1.25 to 3 GHz. The antenna is constructed from two copper layers of rectangular radiator and a partial ground plane. These layers are printed on an RO4003 substrate with dimensions 60 x 80 mm2. The antenna is experimentally fabricated to verify the simulation predictions and good matching between simulated and measured results is achieved. The wide-band antenna is tested by connecting it to the receiver of the Blade-RF Software Defined Radio (SDR) platform. A matlab script is then used to control the SDR board and to perform Spectrum Sensing for Cognitive Radio Applications.

scholarly journals A Cylindrical Wideband Conformal Fractal Antenna for GPS Application

2017 ◽  
Vol 6 (3) ◽  
pp. 64
Author(s):  
R. Sahoo ◽  
D. Vakula
Keyword(s):  
Conformal Geometry ◽  
Ground Plane ◽  
Antenna Design ◽  
Fractal Antenna ◽  
Frequency Range ◽  
Bandwidth Enhancement ◽  
Conformal Antenna ◽  
Operating Frequency Range ◽  
Definition Of ◽  
Good Agreement

In this paper, a novel wideband conformal fractal antenna is proposed for GPS application. The concepts of fractal and partial ground are used in conformal antenna design for miniaturization and bandwidth enhancement. It comprises of Minkowski fractal patch on a substrate of Rogers RT/duroid 5880 with permittivity 2.2 and thickness of 0.787mm with microstrip inset feed. The proposed conformal antenna has a patch dimension about 0.39λmm×0.39λmm, and partial ground plane size is 29mm×90mm.The proposed antenna is simulated, fabricated and measured for both planar and conformal geometry, with good agreement between measurements and simulations. The size of the fractal patch is reduced approximately by 32% as compared with conventional patch. It is observed that the conformal antenna exhibits a fractional bandwidth(for the definition of -10dB) of 43.72% operating from 1.09 to 1.7GHz, which is useful for L1(1.56-1.58GHz), L2(1.21-1.23GHz), L3(1.37-1.39GHz), L4(1.36-1.38GHz), and L5(1.16-1.18 GHz) in GPS and Galileo frequencies: E=1589.742MHz(4MHzbandwidth), E2=1561. 098MHz(4MHzbandwidth), E5a=1176.45MHz(=L5),E5b= 1207.14MHz, and E6=1278.75MHz(40MHz bandwidth). The radiation pattern exhibits an omnidirectional pattern, and gain of proposed antenna is 2.3dBi to 3.5dBi within operating frequency range.

scholarly journals Genetic Algorithms in Antennas and Smart Antennas Design Overview: Two Novel Antenna Systems for Triband GNSS Applications and a Circular Switched Parasitic Array for WiMax Applications Developments with the Use of Genetic Algorithms

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Stylianos C. Panagiotou ◽  
Stelios C. A. Thomopoulos ◽  
Christos N. Capsalis
Keyword(s):  
Genetic Algorithms ◽  
Impedance Matching ◽  
Ground Plane ◽  
Smart Antennas ◽  
Antenna System ◽  
Antenna Design ◽  
Impedance Bandwidth ◽  
Parasitic Array ◽  
Extensive Reference ◽  
Antenna Systems

Genetic algorithms belong to a stochastic class of evolutionary techniques, whose robustness and global search of the solutions space have made them extremely popular among researchers. They have been successfully applied to electromagnetic optimization, including antenna design as well as smart antennas design. In this paper, extensive reference to literature related antenna design efforts employing genetic algorithms is taking place and subsequently, three novel antenna systems are designed in order to provide realistic implementations of a genetic algorithm. Two novel antenna systems are presented to cover the new GPS/Galileo band, namely, L5 (1176 MHz), together with the L1 GPS/Galileo and L2 GPS bands (1575 and 1227 MHz). The first system is a modified PIFA and the second one is a helical antenna above a ground plane. Both systems exhibit enhanced performance characteristics, such as sufficient front gain, input impedance matching, and increased front-to-back ratio. The last antenna system is a five-element switched parasitic array with a directional beam with sufficient beamwidth to a predetermined direction and an adequate impedance bandwidth which can be used as receiver for WiMax signals.

scholarly journals Design of Transparent Antenna for 5G Wireless Applications

Proceedings ◽  
2020 ◽  
Vol 63 (1) ◽  
pp. 54
Author(s):  
Sanae Azizi ◽  
Laurent Canale ◽  
Saida Ahyoud ◽  
Georges Zissis ◽  
Adel Asselman
Keyword(s):  
Patch Antenna ◽  
Return Loss ◽  
Ground Plane ◽  
Antenna Design ◽  
Impedance Bandwidth ◽  
Light Weight ◽  
Frequency Bandwidth ◽  
Frequency Range ◽  
Wireless Applications ◽  
Compact Size

This paper presents the design of a compact size band patch antenna for 5G wireless communications. This wideband antenna was designed on a glass substrate (12 × 11 × 2 mm3) and is optically transparent and compact. It consists of a radiation patch and a ground plane using AgHT-8 material. The antenna design comprises rectangular shaped branches optimized to attain the wideband characteristics. The calculated impedance bandwidth is 7.7% covering the frequency range of 25 to 27 GHz. A prototype of the antenna and various parameters such as return loss plot, gain plot, radiation pattern plot, and voltage standing wave ratio (VSWR) are presented and discussed. The simulated results of this antenna show that it is well suited for future 5G applications because of its transparency, flexibility, light weight, and wide achievable frequency bandwidth near the millimeter wave frequency band.

scholarly journals A Frequency Agile Semicircular Slot Antenna For Cognitive Radio System

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Rajeev Kumar ◽  
Ritu Vijay
Keyword(s):  
Frequency Tuning ◽  
Ground Plane ◽  
Wide Frequency Range ◽  
Slot Antenna ◽  
Frequency Range ◽  
Gain Bandwidth ◽  
Radio System ◽  
Slot Length ◽  
Tuning Ratio ◽  
Frequency Agile

A frequency agile antenna is proposed with its ground plane having a semicircular shaped slot which is capable of switching the frequency to different bands, one at a time, in the wide frequency range of 5.33 GHz to 9.90 GHz. To achieve frequency agility, switching of six RF PIN diodes which are placed along the slot length is done in various combinations. Frequency tuning ratio of about 1.85 : 1 can be achieved using this design. Results such as return losses, gain, bandwidth, and radiation patterns are presented in this paper.

scholarly journals A Modified Square Patch Antenna with Rhombus slot for High bandwidth

2019 ◽  
Vol 8 (9) ◽  
pp. 1580-1583
Keyword(s):  
Patch Antenna ◽  
Communication Systems ◽  
Return Loss ◽  
Impedance Matching ◽  
Antenna Design ◽  
Additional Increase ◽  
Quarter Wavelength ◽  
High Bandwidth ◽  
5G Communication ◽  
Geometrical Dimensions

In this the proposed patch antenna operates at 32 GHz which is among the projected 5G communication frequencies and has a novel geometry with rhombus-shaped slots. The first design in this work is a inset fed used conventionally in patch antenna. It has a quarter wavelength impedance matching line. The dimensions are determined according to the usual design considerations. Low return loss and high bandwidth requirements motivates us to modify the antenna design. Therefore, we add rhombus – shaped slots on the patch which leads to an additional increase in the system bandwidth as much as 52 MHz and a reduction in the return loss level up to 11.241 dB. The proposed patch antenna design is conjectured to be a suitable candidate to address the requirements of 5G communication systems. The operating frequency of the proposed antenna can be tuned by changing the geometrical dimensions from microwave to the THz region.

Visualization of Acoustic Pressure Radiation From Complex Vibrating Structures

1999 ◽  
Author(s):  
Nassif Rayess ◽  
Sean F. Wu
Keyword(s):  
Acoustic Pressure ◽  
Complex Structure ◽  
Excitation Frequency ◽  
High Fidelity ◽  
State University ◽  
Passenger Vehicle ◽  
Frequency Range ◽  
Wayne State University ◽  
Front End ◽  
Helmholtz Equation Least Squares

Abstract This paper demonstrates visualization of the radiated acoustic pressures from a complex structure by using the Helmholtz Equation Least Squares (HELS) method (Wang and Wu, 1997; Wu and Wang, 1998; Wu and Yu, 1998). The structure under consideration has the same geometry and dimensions as those of a real, full-size passenger vehicle front end. Random noises generated by a high-fidelity loudspeaker installed inside the vehicle buck are measured at certain distances away from the vehicle surface. These measured signals are taken as the input to a computer model based on the HELS method. Experiments are conducted inside a 12’ by 12’ by 6.5’ walk-in size, fully anechoic chamber at the Acoustics, Vibration and Noise Control Laboratory of Wayne State University. The reconstructed acoustic pressures on the vehicle buck surface and in the field are compared with the measured data at the same locations. Also shown are comparisons of the reconstructed and measured acoustic pressure spectra at various locations on the vehicle buck surface. Results show that good agreements can be obtained with relatively few expansion functions in the low-to-mid frequency range. The accuracy of reconstruction, however, decreases with the increase of the excitation frequency and measurement distance as expected. Nevertheless, the HELS method is shown to be relatively insensitive to the complexities of a vibrating structure, which may make it potentially a viable noise diagnostic tool for engineers.

scholarly journals UWB Single Port Log Periodic Toothed Terahertz Antenna Design Based on Graphene Artificial Magnetic Conductor

2017 ◽  
Vol 11 (3) ◽  
pp. 86 ◽  
Author(s):  
Hussein A. Abdulnabi ◽  
Refat T. Hussein ◽  
Raad S. Fyath
Keyword(s):  
Chemical Potential ◽  
Single Port ◽  
Impedance Matching ◽  
Ultra Wideband ◽  
Antenna Design ◽  
Frequency Range ◽  
Magnetic Conductor ◽  
Dc Voltage ◽  
Artificial Magnetic Conductor ◽  
Log Periodic Antenna

In this work, a single port exponential tapered toothed log periodic antenna based on graphene artificial magnetic conductor (AMC) is suggested for ultra-wideband (1–10) THz operation. The resonance frequency of the proposed antenna can be tuned by changing the connected DC voltage which leads to variation in the chemical potential of the graphene.The radiating toothed log periodic antenna consists of gold patch placed on 25x25 graphene patches which act as an AMC surface unit. Exponential taper is used to satisfy impedance matching between the antenna and the feeder over the frequency range. The simulation results reveal that 90% of frequency range satisfies when the chemical potential is1eV.

Flexible and moon-shaped slot UWB implantable antenna design for head implants

2017 ◽  
Vol 9 (8) ◽  
pp. 1559-1567 ◽  
Author(s):  
Roshanak Elyassi ◽  
Gholamreza Moradi
Keyword(s):  
Flexible Substrate ◽  
Impedance Matching ◽  
Human Head ◽  
Mean Value ◽  
Ultra Wideband ◽  
Antenna Design ◽  
Frequency Range ◽  
Antenna Performance ◽  
Implantable Antenna ◽  
Simulation Results

In this paper, we present a novel flexible moon-shaped slot implantable antenna for neural recording systems and head implants. It covers both medical Industrial, Scientific and Medical band (2.45 GHz) and impulse ratio ultra-wideband (IR-UWB) frequency range (3.1–10.6 GHz) for forward and backward telemetry applications. It has a simple and miniaturized structure in comparison with the antennas reported in the other researches. Furthermore, for adapting with natural curvature of human head, a flexible substrate is chosen with a good antenna performance under the bending. The proposed antenna is analyzed in a multi-layer box model of head tissues to speed up the antenna design procedures. On the basis of the simulation results, we achieved the good impedance matching over the desired frequency range (S11below −10 dB). Far-field characteristics are considered, as well. The directivity is in suitable range for UWB short-range communications and its mean value is 3.84 dBi. Finally, to take into account patents’ safety regulations and the effective isotropic radiated power restriction in the desired frequency range, the maximum power of transmitter has been calculated. A phantom containing a mixture of sugar and water is used to test the fabricated antenna. The measured parameters are well matched to the full-wave simulation results.

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