• Journal of Advanced Navigation Technology
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• v.28 no.1
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• pp.136-141
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• 2024

In this paper, a broadband inset-fed microstrip patch antenna operating at 10.525 GHz band was proposed. The proposed broadband inset-fed microstrip patch antenna consists of three narrow rectangular patches. At the center of the center patch, two symmetrical side patches were connected by a strip conductor and were arranged with their centers shifted in a perpendicular direction with respect to the center patch. For performance comparison, a conventional inset-fed square microstrip patch antenna was designed. Experiment results show that the frequency band of the measured input reflection coefficient with a voltage standing wave ratio less than 2 for the broadband inset-fed microstrip patch antenna was 10.036-11.051 GHz (9.63%), whereas that for the conventional inset-fed rectangular microstrip patch antenna was 10.306-10.772 GHz (4.42%). Therefore, the input reflection coefficient frequency bandwidth of the fabricated broadband inset-fed microstrip patch antenna was increased by 2.18 times, compared to the conventional inset-fed square microstrip patch antenna.

• Journal of Advanced Navigation Technology
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• v.27 no.1
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• pp.71-76
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• 2023

In this paper, a humidity sensor using a microstrip patch antenna(MPA) and polyvinyl alcohol(PVA) is studied. PVA is a polymer material whose permittivity changes with humidity, and a rectangular slot is added to the radiating edge of the MPA, which is sensitive to changes in electric field, in order to increase the sensitivity to changes in relative permittivity. After thinly coating the area around the radiating edge with the rectangular slot of the MPA fabricated on a 0.76 mm-thick RF-35 substrate with PVA, the changes in the resonant frequency and magnitude of the MPA's input reflection coefficient are measured when relative humidity is adjusted from 40% to 80% in 10% increments at a temperature of 25 degrees using a temperature and humidity chamber. Experiment results show that when the relative humidity increases from 40% to 80%, the resonance frequency of the antenna' input reflection coefficient decreases from 2.447 GHz to 2.418 GHz, whereas the magnitude increases from -7.112 dB to -3.428 dB.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.5
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• pp.772-772
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• 2001

In this paper, we proposed the image-based 3D ray-tracing indoor propagation model using patch scattering model which can calculate the scattering phenomenon of the indoor structures. A patch scattering model for modeling indoor structures defines a scattering phenomenon by using RCS(Radar Cross Section) about rectangular patch without complex calculation, for example generating image antennas about each indoor structures. RCS is simply defined as a ratio of scattering power to incident power, and we use bistatic PCS which is simplified numerically by Physical Optics. Also, a simple indoor compensation factor is defined as empirical constant from measured data instead of complex numerical expression because basic patch scattering model cannot include important multipath components, so we san use patch scattering model in indoor environment using indoor compensation factor.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.5
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• pp.722-733
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• 2001

In this paper, we proposed the image-based 3D ray-tracing indoor propagation model using patch scattering model which can calculate the scattering phenomenon of the indoor structures. A patch scattering model for modeling indoor structures defines a scattering phenomenon by using RCS(Radar Cross Section) about rectangular patch without complex calculation, for example generating image antennas about each indoor structures. RCS is simply defined as a ratio of scattering power to incident power, and we use bistatic PCS which is simplified numerically by Physical Optics. Also, a simple indoor compensation factor is defined as empirical constant from measured data instead of complex numerical expression because basic patch scattering model cannot include important multipath components, so we san use patch scattering model in indoor environment using indoor compensation factor.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.2
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• pp.245-252
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• 2016

In this paper, the design of a double-dipole quasi-Yagi antenna (DDQYA) with a gain over 7 dBi at 1.70-2.70 GHz band is studied. The proposed DDQYA consists of two strip dipoles with different lengths and a ground reflector, which are connected trough a coplanar stripline. The length of the second dipole is adjusted to increase the gain in the low frequency band, whereas a rectangular patch director is appended to the DDQYA to enhance the gain in the middle and high frequency band. The effects of the length of the second dipole, and the length and width of the director on the antenna performance are analyzed, and final design parameters to obtain a gain over 7 dBi are obtained. A prototype of the proposed DDQYA is fabricated on an FR4 substrate, and the experimental results show that the antenna has a frequency band of 1.60-2.86 GHz for a VSWR < 2, and measured gain ranges 7.2-7.6 dBi at 1.70-2.70 GHz band.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.12
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• pp.8-13
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• 1997

In this paper, the input impedance and efficiency of rectangulr microstip patch antenna located inside a rectangular wavegudie is calculated by using the cavity model and the mode excited by te patch antenna which is modeled as an equivanlent surface magnetic current on the conducting plate. Measured return losses of a rectangular microstrip patch antenna tuned at 5.93 GHz in the free space and inside the retangular waveguide are compared and found to be in good agreement with calculated results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.3
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• pp.535-540
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• 2004

In this paper, We proposed a rectangular slot antenna with CPW feeder. Slot antennas fed by CPW are attractive due to the simple fabrication simplicity and ease of integration with active devices. This antenna consists of two parts, inner patch and outer patch to realize wide-band antenna by multi-frequency. Also, We fabricated a proposed rectangular slot antenna, confirm characteristics of multi-frequency by tuning antenna parameters, inner antenna's location and size. The experimental results show that each resonant frequency of a fabricated antenna is measured at almost 1, 9GHz, 2.8GHz, 3, 5GHz, 4, 9GHz. In radiation patterns each resonant frequency, radiation pattern 4-th resonant frequency is the same ad that of TM11 in patch antenna. Therefore, the experimental and theoretical results shows that a proposal rectangular slot antenna have triple resonant frequencies.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.8
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• pp.1785-1790
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• 2014

In communication systems, there are various types of microstrip antenna that can be used for many applications. This paper mainly focuses on the simple design of inset fed rectangular microstrip patch antenna to operate at frequency of 2.45 GHz for wireless communication. The study involves using HFSS simulator to design the antenna dimensions and to determine its performance. This antenna is based on a thickness of 1.6mm Teflon substrate with a dielectric constant of approximately 2.2, on one side of the substrate and another side has a ground plane. After simulation, the antenna performance characteristics such as return loss, VSWR, gain, radiation pattern are obtained.

• Journal of Advanced Navigation Technology
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• v.12 no.5
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• pp.420-428
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• 2008

In this paper, Stack structure patch antenna has been designed and fabricated for wireless LAN applications. The patch and ground plane were used by PEC metal. It was 0.05 [mm] thick. In order to broaden the bandwidth of the antenna and improve of gain, the stack structured antenna with probe feed. The measured input return loss showed less than -10 [dB] at the broadband from 5100 to 6140 [MHz]. It's measured bandwidth was 1040 MHz. The gain of antenna in the E-plane and H-plane was 13 dBi and 3 dB beam width was $40^{\circ}$.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.8 s.350
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• pp.103-109
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• 2006

In this paper, single-feed equilateral triangular microstrip antennas(ETMA) for circular polarization(CP) are designed and studied experimentally. It is demonstrated that by embedding a narrow slot or a cross of unequal slot lengths in the triangular patch circularly polarized radiation RHCP(right-hand circularly polarized wave), LHCP(left-hand circularly polarized wave) of microstrip antennas can easily be achieved using by strategically positioned coaxial single probe feed. And the size of a triangular microstrip patch antenna is smaller than that of a conventional rectangular or circular patch at a given frequency. A single-feed ETMA with a horizontal narrow slot is printed on the substrate of 60 mils thick and the other ETMA with a corss slot of unequal slot lengths is printed on the same substrate. The antenna radiation characteristics are calculated by ENSEMBLE(Ver. 5.0) software, and compared with the experimental results. This results show that the antenna size reduction of about $17%{\sim}2l%$ is obtained as compared to the regular-size CP design.