• Journal of information and communication convergence engineering
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• v.13 no.3
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• pp.159-166
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• 2015

In this paper, a novel design for a triple-band coplanar waveguide (CPW)-fed monopole antenna for WLAN/WiMAX operations is proposed. The proposed antenna is printed on an FR4 substrate with an area of 22.0 mm × 30.0 mm, a thickness of 1.0 mm, and a relative permittivity of 4.4. The effects of various parameters of the proposed for triple band operation is investigated. Two half circular rings and a microstrip feed line are fabricated on the substrate to achieve triple band operation and good impedance matching. Prototypes of the proposed antenna have been fabricated and tested. Experiment results reveal that the measured return loss exhibits an acceptable agreement with the simulated return loss and satisfies the impedance bandwidth requirement of -10 dB, while simultaneously covering the WLAN and WiMAX bands. In addition, the proposed antenna shows good radiation characteristics and gains in the three operating bands.

• Journal of Advanced Navigation Technology
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• v.25 no.6
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• pp.536-542
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• 2021

In this paper, we proposed a triple band printed monopole antenna with a bent branch strips for WiFi / 5G. An antenna structure in which bent strips for generating multiple resonance are attached in the form of branches was newly proposed based on a typical monopole strip vertically erected as a triple band antenna structure. The proposed antenna is designed on a FR-4 substrate with dielectric constant 4.3, thickness of 1.6 mm, and size of 28×40 mm². The measured impedance bandwidth is 430 MHz (2.22~2.65 GHz) in the 2.4 GHz WLAN, 450 MHz (3.38~3.83 GHz) in the 3.5 GHz and 2390 MHz (4.95~7.34 GHz), In particular, it has been observed that antenna has a stable omnidirectional radiation patterns as well as gain of 1.537 dBi, 1.878 dBi and 2.337 dBi in the entire frequency band of interest.

• Journal of electromagnetic engineering and science
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• v.14 no.1
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• pp.31-35
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• 2014

An ultra-wideband (UWB) circular monopole antenna with a multiband-notched characteristic is proposed. The multiband-notched filter consists of three different sized folded slots, which are distinctly assigned for the notched band at the 3.5-GHz WiMAX, 5-GHz WLAN, and 8-GHz ITU bands. The proposed antenna results in a measured ${\mid}S_{11}{\mid}$ < -10 dB, which completely covers the UWB band (3.1 10.6 GHz) with three notched bands at 3.5, 5.5, and 8.0 GHz. The antenna yields an omnidirectional radiation pattern and high radiation efficiency.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.6 s.97
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• pp.563-570
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• 2005

In this paper, a small-sized planar square-spiral monopole antenna is proposed by using parasitic elements. The Parasitic element is composed of a crossed strip and additional right-angle folded(L-type) stirps. And these parasitic elements are printed on a substrate which is the opposite side of a radiation element . When the parasitic elements are used, the size of the square-spiral monopole antenna is reduced by $32\%$ for the same operating frequency compared to the antenna without parasitic elements. The radiation pattern of the proposed antenna is nearly omni-directional in azimuth. The designed antenna can be used in the application of channel 12 digital mulimedia broadcasting(DMB) handset.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.12
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• pp.1659-1665
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• 2019

In this paper, a novel design of a compact printed monopole antenna for wireless local area network (WLAN) applications is investigated. The radiator with a patch of different line width and step-shaped ground planes is used to reduce the antenna size. The size of the antenna is 16 × 17 × 1 ㎣ and is fabricated with a photolithography technique. The simulated and measured results agree well. The resonant frequency of the investigated antenna is about 5.2 GHz and can cover an impedance bandwidth of 1 GHz for the measurement result. In addition, we presented the measured radiation pattern, presented the gain and efficiency measured in the required WLAN 5 GHz frequency band (5.15-5.825 GHz), and confirmed that it can be used as a 5 GHz band WLAN antenna. The investigated antenna has a small size, light weight, low cost, omni-directional radiation pattern, high gain, and high efficiency.

• Journal of Electrical Engineering and Technology
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• v.12 no.4
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• pp.1611-1618
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• 2017

This paper presents a compact reconfigurable printed monopole antenna, operating in three different frequency bands (2.45 GHz, 3 GHz and 5.2 GHz), depending upon the state of the lumped element switch. The proposed multiband reconfigurable antenna is designed and fabricated on a 1.6 mm thicker FR-4 substrate having a relative permittivity of 4.4. When the switch is turned ON, the antenna operates in a dual band frequency mode, i.e. WiFi at 2.45 GHz (2.06-3.14 GHz) and WLAN at 5.4 GHz (5.11-5.66 GHz). When the switch is turned OFF, it operates only at 3 GHz (2.44-3.66 GHz). The antenna radiates omni-directionally in these bands with an adequate, bandwidth (>10 %), efficiency (>90 %), gain (>1.2 dB), directivity (>1.7 dBi) and VSWR (<2). The fabricated antenna is tested in the laboratory to validate the simulated results. The antenna, due to its reasonably compact size ($39{\times}37mm^2$), can be used in portable devices such as laptops and iPads.

• Journal of Advanced Navigation Technology
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• v.19 no.6
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• pp.623-629
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• 2015

In the present study, a coplanar waveguide (CPW)-fed printed monopole antenna with an inverted n-shaped slot is newly proposed for dual band operations which cover bandwidths of CDMA (1.85~2.025 GHz) and WLAN (2.4~2.484 GHz) as well as implementation of omnidirectional radiation pattern. For enhancement of impedance bandwidth ($S11{\leq}10dB$) in 2.4 GHz WLAN frequency band, an inverted n-shaped slot instead of the previous n-shaped slot is etched on the printed radiating monopole. The proposed antenna is designed and fabricated on one side of FR4 substrate with dielectric constant of 4.4, thickness of 1.6 mm, and size of $50{\times}25mm^2$. It has been observed that the measured impedance bandwidths are 280 MHz (1.84~2.12 GHz) in frequency band of CDMA and 420 MHz (2.38~2.8 GHz) in WLAN frequency band respectively. It is noticeable that impedance bandwidth in 2.4 GHz frequency band of WLAN is enlarged to three times due to use of inverted L-shaped slot in comparison with impedance bandwidth 140 MHz (2.39~2.53 GHz) obtained by use of the previous n-shaped slot. In addition, good omnidirectional radiation patterns have been observed over the entire frequency band of interest.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.1 s.116
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• pp.82-89
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• 2007

This paper presents a coplanar waveguide fed L-planar type monopole antenna which covers ultra wideband(UWB) region of 3.1 GHz to 10.6 GHz. The proposed UWB L-planar type monopole antenna is designed and implemented on the organic substrates( ${\varepsilon}_{r}=3.38,\;@10\;GHz$). The radiation elements, feed line, and ground planes of the antenna are printed on the same conductive layer of the substrates. The bandwidth of the proposed antenna is measured in the range of 3.0 GHz to 11.0 GHz. The measured radiation patterns are symmetrical in E-plane and omni-directional in H-plane. Antenna gains ranges from 1.4 dBi to 4.6 dBi. The proposed UWB antenna shows that the structure is adequate for the design of RFIC.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.4
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• pp.86-96
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• 2008

In this paper, a new broadband rectenna is presented for the wireless transmission of microwave power. The new broadband rectenna element is based on a new printed monopole broadband antenna with size reduction using surface current distribution and a new broadband stub bandpass filter with suppression of second harmonics. A RF-to-DC conversion efficiency of 80% using a 270 ohm load resistor is obtain at 2.45 GHz. Also, a conversion efficiency of above 50 % is maintained from 1.8 GHz to 2.8 GHz.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.9
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• pp.1633-1640
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• 2016

In this paper, we propose a open-ended rectangular microstirp patch antenna with fork-shaped feeding structure. This antenna extends the effective bandwidth by transforming single or multi resonant frequency and is designed planar monopole structure with microstrip line to satisfy the WLAN bands (2.4 - 2.484, 5.15 - 5.35, 5.25-5.825 GHz). The substrate is printed in 0.8 mm thickness on an FR-4 board. A commercial 3D simulation tool was used to analyze surface current and electromagnetic field distribution in order to analyze the operation mode and reconfiguration principle of antenna. According to the lengths of individual patches, simulated reflection loss was compared to obtain optimized values. When it was designed with the optimized values, it satisfied WLAN bands (2.380 - 2.710, 4.900 - 5.950 GHz), if the switch is off, and 2.4 WLAN band (2.380 - 2.710 GHz). From the fabricated and measured results, measured results of return loss, gain and radiation patterns characteristics displayed for operating bands.