• Journal of Advanced Navigation Technology
• /
• v.20 no.5
• /
• pp.490-495
• /
• 2016

In the present study, a microstrip-fed monopole antenna is proposed for wireless local area network (WLAN) operations which cover dual band of 2.4 GHz (2.4 ~ 2.484 GHz) and 5 GHz (5.15 ~ 5.825 GHz). In order to obtain its compact structure and good omnidirectional radiation patterns, a modified inverted L-shaped slot separated from ground for impedance matching in 5 GHz band is etched on 2.4 GHz printed monopole antenna. The proposed antenna is designed and fabricated on a FR4 substrate with dielectric constant 4.3, thickness of 1.6 mm, and size of $30{\times}45mm^2$. The measured impedance bandwidths (${\mid}S_{11}{\mid}{\leq}-10dB$) of fabricated antenna are 270 MHz (2.22 ~ 2.48 GHz) in 2.4 GHz band and 890 MHz (5.08 ~ 5.97 GHz) in 5 GHz band respectively. In particular, high gain of more than about 4 dBi and good omnidirectional radiation patterns have been observed over the entire frequency band of interest.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.25 no.10
• /
• pp.1040-1049
• /
• 2014

In this paper, a quad-band antenna for DCS1800, PCS1900, WCDMA, WLAN and Mobile WiMAX application is proposed. The proposed antenna is a printed monopole structure, and consists of two rectangular ring-shaped radiating patches on the front side and two different size of L-shaped slots on the back side(ground plane). Two rectangular ring radiation patches are respectively resonant at 2 GHz and 3.5 GHz bands, and additional resonance is occurred at 5.3 GHz by the coupling effect between two ring patches. In addition, the optimized matching characteristic is obtained by controlling the gaps. Also, by adding two L-slots on the ground plane, additional resonant frequency band of 5.6 GHz is occurred. Finally the measured bandwidths of the proposed antenna below -10 dB return loss are 1,200 MHz(1.6~2.8 GHz), 800 MHz(3.2~4.0 GHz), 300 MHz(5.14~5.44 GHz), and 690 MHz(5.56~6.25 GHz). The radiation patterns have the omni-directional characteristic, and the measured antenna average gains at resonant bands are 0.86~4.07 dBi.

• Proceedings of the IEEK Conference
• /
• 2004.06a
• /
• pp.151-154
• /
• 2004

In this paper. we present the 2.4 GHz and 5 GHz dual band antenna for a multiple PCB (Printed Circuit Board) antenna. Using antenna has a monopole structure with lines on FR-4(${\varepsilon}_r\;{\approx}\;4.6$) PCB. The obtained antenna can perform in 2.4 GHz and 5 GHz bands and be adopted for other wireless applications.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.45 no.7
• /
• pp.72-76
• /
• 2008

In this paper, the several printed square loop antennas which modified monopole antennas are proposed. The proposed antennas are reduced about 20% physical size of antenna and miniaturized reactance value of impedance due to fold center part of the loop. They obtained omni-directional radiation patterns with broad bandwidth and feed method used coplanar waveguide to composed single planar. The proposed antenna bandwidth is about 900MHz($2.63{\sim}3.56GHz]$) resonance frequency on $VSWR{\le}2$. it can be sufficiency of S-DMB band.

• Journal of Advanced Navigation Technology
• /
• v.13 no.6
• /
• pp.838-845
• /
• 2009

In order to obtain magneto-dielectrics with various permmittivity and permeability which could be used as the antenna substrate, various magneto-dielectrics compounded of dielectric materials(such as silicon and epoxy resin) and magnetic materials(such as carbonyl iron, barium and strontium powder) were fabricated. The relative permittivity and permeability of those were measured by use of HP 4291B impedance analyzer. Based upon the measured results, inverted-F meander monopole antennas(IFA) which were printed on the magneto-dielectric substrates fabricated as film type were designed and fabricated to investigate into variations of antenna characteristics such as the resonant frequency and impedance bandwidth in comparison with use of dielectric substrate. Some simulated and measured results for the designed IFA were presented. Characteristics of magneto-dielectrics which are different according as the choice of magnetic material or the composition ratio between magnetic material and dielectric material is different have been discussed.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.22 no.5
• /
• pp.568-575
• /
• 2011

In this paper, we propose a small broadband antenna for mobile device. The proposed antenna consists of a printed rectangular monopole antenna and a parastic element connected to ground using narrow meander line and it is designed on a FR-4 substrate that has a thickness of 0.8 mm and a dielectric constant of 4.4. The FR-4 substrate's size is 50 mm${\times}$90 mm comparable to the real mobile device. The fabricated antenna's size is 12.5 mm${\times}$10.5 mm${\times}$0.8 mm and the measurement shows -10 dB return loss bandwidth of 2,200~6,000 MHz and gains of 2.86~4.01 dBi. Accordingly, the proposed antenna can support mobile device for WiBro(2,300~2,380 MHz), WLAN(IEEE 802.11b/g/n: 2,400~2,480 MHz, IEEE 802.11a: 5,150~5,825 MHz), and mobile WiMAX(IEEE 802.16e : 2,500~2,690 MHz, 3,400~3,600 MHz) service bands.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.20 no.3
• /
• pp.230-239
• /
• 2009

In this paper, we propose a novel on-glass antenna for FM radio reception in a recreation vehicle(RV). We use a multi-loop structure that takes advantage of a broad matching bandwidth and a high vertical radiation gain by efficiently utilizing a given space of a quarter glass in spite of the simple planar structure. Transparency of the antenna is also improved by adjusting the stripline widths based on the induced current distributions. The proposed antenna is printed on a quarter glass of a commercial vehicle and antenna performances such as the return loss and the gain are measured in a semi-anechoic chamber. The result shows the average gain of -9.67 dBi along the bore-sight direction($\theta=90^{\circ}$, $\phi=270^{\circ}$) in the FM radio band(80$\sim$l10 MHz), which is higher than a commercial monopole typed on-glass antenna($G_{ave}$=-12.49 dBi) and micro-antenna($G_{ave}$=-19.24 dBi) mounted on the roof of the RV.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.17 no.11 s.114
• /
• pp.1021-1029
• /
• 2006

In this paper, we designed and implemented a dual wideband dipole type antenna for the reception of S-DMB (Satellite Digital Multimedia Broadcasting) and 2.4/5 GHz WLAN(Wireless Local Area Network) signals. The proposed antenna based on conventional monopole type dual band antenna was implemented as planar wideband dipole type antenna with the volume of $8{\times}33.8{\times}1.68mm^3$. The proposed antenna is printed type on FR4 substrate of 1.6 mm thick and composed of a dipole type antenna for low frequency band and two symmetric structured resonance elements for high frequency band. We confirmed antenna area with dense surface current for each frequency band with simulation. By varying the length of the antenna area with dense surface current, we could vary resonance frequency of each frequency band separately. Impedance bandwidths$(VSWR{\leq}2)$ are 362 MHz(14.23 %) for 2 GHz band and 1188 MHz(22.13, %) for 5 GHz band which show wideband characteristic. Measured maximum gains were 4.33 dBi for 2 GHz band and 5.48 dBi for 5 GHz band which showed improved performance. And the implemented antenna has a good omni-directional radiation pattern characteristic.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.20 no.10
• /
• pp.1031-1041
• /
• 2009

A small microstrip monopole antenna for macro-micro frequency tuning over multiple bands is presented. The meander-shape antenna is fabricated on a conventional printed circuit board(FR-4, $\varepsilon_r=4.4$ and tan $\delta=0.02$). The antenna operates over WiBro(2.3~2.4 GHz) and WLAN a/b(2.4~2.5 GHz/5.15~5.35 GHz) service bands with an essentially constant antenna gain within each service band. Two diodes, a PIN diode and a varactor, are embedded into the antenna for frequency reconfiguration. The PIN diode is used for frequency switching(macro-tuning) between 2 GHz and 5 GHz bands while the varactor is used for frequency tuning(micro-tuning) within the service bands, 2.3~2.5 GHz and 5.15~5.35 GHz. Unwanted resonances between the two frequency bands(2 GHz and 5 GHz) are suppressed by filling up the gaps between the meander lines. The antenna gain is essentially constant and higher than 2 dBi within each service band. The measured performance of the proposed antenna system suggests the macro-micro frequency tuning techniques be useful in reconfigurable wireless communication systems.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.21 no.6
• /
• pp.706-713
• /
• 2010

In this paper, the small loop antenna with a parasitic loop structure for penta-band mobile phone application is proposed. This antenna is composed of a feed monopole, a radiating loop antenna with a parasitic loop structure and an additional radiating element. The antenna is printed on the very thin flexible substrate to mount on the dielectric carrier with a volume of 40 mm$\times$11 mm$\times$3 mm. The bandwidth of the proposed antenna is 402 MHz(773~1,175 MHz) for low band and 583 MHz(1,622~2,205 MHz) for high band. As a result, the proposed antenna covers the five bands of GSM850, GSM900, DCS1800, PCS1,900 and WCDMA for a 3:1 VSWR. Moreover, the radiation pattern, gain and efficiency are appropriate for mobile handset. Therefore, this antenna is suitable for small sized multi-band mobile handset applications.