• ETRI Journal
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• v.31 no.5
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• pp.616-618
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• 2009

In this letter, a novel hybrid planar inverted-F antenna (PIFA) with a T-shaped slot on the ground plane is proposed. The loop structure formed by the feed line and shorting pin can be operated as a series and shunt inductance for the PIFA and the T-shaped slot antenna, respectively. The PIFA operates at a frequency of 1.75 GHz, while the T-shaped slot on the ground plane operates at 2.4 GHz by the same voltage feeding source. The height of the PIFA is 6.5 mm, and the size of an upper patch is designed to be 30 mm${\times}$16 mm. The measured relative impedance bandwidth of the PIFA and the T-shaped slot are about 12% and 21%, respectively. In addition, good antenna performance was achieved.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.5
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• pp.630-639
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• 1998

In this paper, a T-shaped microstrip feed line is proposed for a better impedance matching to the microstrip slot antenna in a various range of slot widths. It was found that the bandwidth of this antenna is proportional to the slot width. It was also found that the radiation resistance of this feed line structure is quite constant and low regardless to the slot width. A slot antenna with T-shaped microstrip feed line is analyzed by using the FDTD method. At first, the propagation process of the reflected wave and the electric field distribution in the time domain is calculated respectively. The antenna parameters also are optimized to get maximum band width, return loss, input impedance, and radiation pattern in the frquency domain by Fourier transforming the time domain results. From the computed results, the optimum slot antenna is designed and fabricated. When the slot width is 16 mm, approximately 35% of bandwidths are obtained without a matching circuit. These computed results using FDTD method were in relatively good accordance with the measured values.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.6
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• pp.110-116
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• 2015

In this paper, a compact low-loss reflector-type phase shifter with harmonic suppression using meander T-shaped branch-line coupler is suggested. The compact coupler for the phase shifter has a size of $22.2{\times}14.9mm^2$ while a conventional branch coupler has a size of $32.6{\times}27.8mm^2$. The phase shifter shows insertion losses of 0.19-0.28 dB at the center frequency of 2.1 GHz, and a measured maximum phase shift of $137^{\circ}$.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.1
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• pp.15-22
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• 2018

In this paper, a microstrip-fed triple-band monopole antenna for WLAN/WiMAX applications was proposed. The proposed antenna is consist of two arc-shaped and one strip line structure, then get the three current path and then designed in order to get triple resonant characteristics. We carried out simulation about parameters. Taking account of coupling effect, Adjusted the length of the two arc-shaped and one strip line, we get the optimized parameters. The proposed antenna is fabricated on an FR-4 substrate, the dielectric constant is 4.4, and total size is $23.5mm(W1){\times}32.0mm(L1){\times}1.0mm(t)$, and its proposed antenna size is $21.0mm(W6){\times}31.0mm(L7)$. From the measured results, return loss of the proposed antenna satisfied return loss 927 MHz (1.844~2.771 GHz), 926 MHz (3.33~4.256 GHz), and 1,415 MHz (5.13~6.545 GHz). And measured results of gain and radiation patterns displayed for operating bands.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.4
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• pp.103-109
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• 1999

In this paper, we proposed to a new structure of T-shaped fed microstrip slot antenna using 2-layers dielectric material with a directional radiation characteristic. When the slot antenna of bi-directional radiation want to radiate only one direction, the reflector must be set up, but this antenna does'nt need set up reflector. T-shaped microstrip feed line is proposed for a better impedance matching to the microstrip slot antenna in a various range of slot widths. It was also found that the bandwidth of this antenna is proportional to the slot width. It was also found that the radiation resistance of this feed line structure is quite constant and low regardless to the slot width. We also analyzed this antenna by using the FDTD method, and calculating waves and electric field distribution in the time domain. we also are calculated return loss, VSWR, and radiation pattern in the frequency domain by Fourier transforming the time domain results, respectively. From the measured results, bandwidth was 34.8% in the center frequency. These results were in relatively good accordance with the calculated values.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.12C
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• pp.759-763
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• 2011

In this paper, a dual-band T-shaped microstrip monopole antenna with a pair of slits for 2.4/5.2/5.8-GHz wireless local area networks (WLANs) is proposed. A pair of T-shaped slits is loaded on a T-shaped monopole antenna fed by microstrip line in order to obtain dual-band operation as well as to reduce the antenna size. It is demonstrated from experimental results that the proposed antenna can cover all the required bands for WLAN. The measured impedance bandwidth for VSWR<2 is about 5.7% (2.37-2.51GHz) in the lower frequency band and about 28.8% (4.76-6.35GHz) in the higher frequency band. The measured peak gains are about 1.33 dBi to 1.66 dBi in the 2.4GHz band, 3.50 dBi to 3.95 dBi in the 5.25GHz band, and 2.06 dBi to 2.34 dBi in the 5.8GHz band.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.4
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• pp.562-569
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• 2001

This paper presents the optimum design method for T-shaped microstrip-line-fed slot antennas on various substrates. Since the impedance bandwidth of the antenna depends highly on the vertical offset position and the length of horizontal strip conductor, we derived the formulas regarding these design parameters to get the maximum bandwidth. The formulas can compute the offset position and the length of horizontal strip conductor for any given substrate parameters. We compared the results obtained by using these design formulas and the one obtained by the simulation for each slot width, and it showed very good agreement.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.4
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• pp.35-40
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• 2022

This paper proposes an antenna that is located outside the PCB substrate of an electronic product to enable wireless communication in the ISM band. The PCB designed the T-shaped OPEN-STUB power supply line to be miniaturized so that it does not interfere with parts or interfere with design. The characteristics of the antenna were confirmed in the 2.4GHz and 5.8GHz bands using a T-shaped stub feeder and a spiral structure. The size of the antenna is 5mm in width × 6.5mm in length, and the thickness of the PCB is 1.2T. As a result of measurement of the manufactured antenna, it was possible to obtain a return loss of -10dB or more at 2.4GHz and 5.8GHz. In the E-plane, the gain was -4.45 dBi, and in the H-plane, the gain was -1.05 dBi. Therefore, the proposed small antenna for wireless communication showed excellent performance.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.552-555
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• 1999

In this paper, a method for extracting the fingerprint regions and the table from fingerprint document which is the size of A4 including ten fingerprints images in a table is presented. The extraction of each fingerprint region is carried out by segmenting the foreground fingerprint region using a block filtering method and detecting its center point. The table extraction, by detecting a horizontal line using line tracing, and detecting a vertical line by its orthogonal equation. Here, T-shaped mask is proposed for finding the starting points of the vertical line intersecting horizontal line by the form of 'T'. Experimental results show above 95% correct rate of extracting the fingerprint region and table.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.5
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• pp.53-59
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• 2010

There are various types of antenna fed method; coaxial probe, coupling, parasitic elements, and impedance matching. In this paper, the fed method of the proposed antenna is microstrip line type. The high frequency structure simulator (HFSS) is used to analyze the characteristics of the T-shaped microstrip antenna with various patch dimensions. In comparison with the basic microstrip antenna, this proposed T-shaped microstrip antenna with 40.38 % of patch dimensions has the optimum characteristics of resonant frequency, return loss, and radiation pattern at 2.0 GHz band.