• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.128-131
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• 2000

This paper describes design for dual-linear polarization antenna using EMC(electromagnetic-coupled) dipole. EMC dipole has a simple element structure and it is fed by microstrip line. Vortical and horizontal polarization are determined by structure of dipole fed by microstrip line. FDTD Method is used for an analysis of antenna element. Length, width, height and offset of dipole are designed for 1-element antenna. Resonant length of diploe differs from the calculated value by a formula because of coupling effect of dipole and feed line. Radiation Power is controlled by the offset of dipole. In prectical fabrication of antenna array, a constant height of dipoles is required. Therefore, the teflon plate with height of 0.8 mm is considered in antenna element design for the vertical polarization.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.3
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• pp.533-540
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• 1999

In this paper, a microstrip antenna is designed using a rectangular patch. To find characteristics of the antenna, computer simulations of the rectangular single microstrip patch antenna are performed with changing width and feed line. And we found characteristics of RHCP using axial ratio. Through the results, we found that the Finite Difference Time Domain(FDTD) method is an effective method for designing microstrip patch antenna. According to simulation the resonant point has been found it in the frequency received from GPS satellite. And these results were in relatively good accordance with the measured values.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.3
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• pp.461-466
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• 2019

In this paper, we have studied the improvement of gain and bandwidth characteristics by using double feeding and L-shaped inset feed line matching circuit in microstrip stacked patch antenna which is widely used to broaden the gain of general microstrip antenna. The proposed structure is composed of two feeding edges of the main patch antenna, each of them are connected to a feeding line having an L shaped inset feeder. And the parasitic patch is placed at a proper distance above the main patch. The size of the main patch is designed so that the resonance frequency is close to the center frequency of the target frequency band. The experimental results show that the bandwidth was increased more than 180MHz in the 2.3-2.7 GHz band, which is more interesting than the single feed, and the gain improvement of 2.5dBi was obtained at 2.7GHz.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.4
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• pp.894-900
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• 2004

There are many types of circularly polarized(CP) microstrip antenna elements, which are used as a good unit radiator. Since an advantage of CP antenna is no strict alignment requirements between Rx and Tx system, the printed antennas with circular polarization are very often used in numerous satellite and mobile radio systems. In order to realize the broad bandwidth of 3 dB axial ratio and impedance of CP microstrip antenna, complex feed structure and tri-plate patch element have been researched. This paper describes a design of wideband microstrip cross slot array antennas with circular polarization. The proposed antenna is composed of an open-ended microstrip feed line as a feeder and a cross slot as a radiator for circular polarization. To realize the wide bandwidth, tri-plate structure are considered and cross slot is electromagnetically coupled with feed line. Optimum parameters of 1-element cross slot antenna are analyzed and designed by method of moments. These parameters are also applied to may antennas design considered the mutual coupling between radiating elements. Right hand circular polarization(RHCP) and left hand circular polarization(LHCP) of the proposed antenna are easily controlled by asymmetrical cross slot structure and slot position. In 1-element and 15-element cross slot array antenna, the good axial ratio of 1 dB below and the broad bandwidth characteristics of antenna are obtained.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.580-583
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• 2007

In this paper, we proposed a slot antenna for dual band ISM that was transformed from a slot antenna structure. Proposed antenna was designed and fabricated that transformed feed line was changed existing slot antenna feed line to appear resonances at dual band. Bandwidth of the designed and fabricated slot antenna for ISM dual band is 8.23%, 4.8% at the resonated frequency at 2.45 GHz, 5 GHz. And we observed the resonant frequency and bandwidth according to change of feed line and slot length. Also, the measured radiation pattern characteristic of fabricated antenna is compared and analyzed E-plane and H-plane at 2.45 GHz, 5GHz.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.5
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• pp.40-45
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• 2008

In this paper, a microstrip linear tapered slot antenna is designed. A tapered slot antenna(TSA) has many advantages such as low profile, low weight, easy fabrication, and compatibility with monolithic microwave integrated circuits(MMIC). In addition, it has demonstrated multi octave bandwidth, moderately high gain, and symmetrical E- and H-plane beam patterns. A feed network is implemented with transition between a microstrip and a slot line for the microstrip linear tapered slot antenna. The transition is consist of two sides. One side has a microstrip line, the other side has a slot line. The dimensions of the microstrip and slot line are ${\lambda}_m/4$ and ${\lambda}_s/4$ at the center of the cross section of the microstrip and slot line. In order to get broad bandwidth antenna characteristics, the tapered length is chosen as $4{\lambda}_o$ and termination width is chosen as $1.75{\lambda}_o$. Experimental results show that the microstrip tapered slot antenna has symmetrical E- and H-plane beam patterns with around 5GHz of bandwidth at center frequency of 5.0GHz.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.10
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• pp.1159-1165
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• 2008

In this paper, a single-feed equilateral-triangular microstrip antenna with truncated corners is used for achieving diverse radiation polarization. The proposed antenna is excited by a microstrip line, which is place parallel to an oblique side of the equilateral-triangular patch. Depending on whether the three identically-sized comers of the triangular patch are cut or not, the equilateral-triangular microstrip antenna shows linear polarization(LP) or left-hand circular polarization(LHCP) or Tight-hand circular polarization(RHCP). Based on the equilateral-triangular microstrip antenna with truncated corners, a novel reconfigurable microstrip antenna with switchable polarization sense is also proposed. The proposed reconfigurable antenna has a simple structure, consisting of a corner-truncated triangular patch, a small triangular conductor, and a microstrip line. Using a biased PIN diode between the patch and the small triangular conductor, it can produce LP or RHCP according to bias voltages. From the measured results, low cross polarization level when operated in the linear state and good axial ratio in the circular state are observed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.10
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• pp.2065-2071
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• 2011

The external quality factor ($Q_e$) is controlled by coupling condition between resonator and input/output ports in design of microwave filter. In this paper, we represent extracting method of external quality factor using phase response for resonator with input/output ports according to position of feed line from microstrip line resonator. The results regarding to position, coupling gap and line width for tapped line and coupled line structure are represented, and we got the exact $Q_e$ value from the this method. This results will be applied to coupled resonator filter design.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.345-349
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• 2000

A microstrip polarized 8${\times}$2 linear phased array antenna with four 4-bit phase shifters is designed at 10 GHz. The 180$^{\circ}$and 90$^{\circ}$ sections of the phase shifter are of the switched line type, and the rests are of the loaded line type. A 2${\times}$2 sequential sub-array is adopted for a broad axial ratio bandwidth. The construction of the array antenna is of the tile type placing the phase shifters on the same layer containing the feed network. The element spacing is chosen to be 0.45λ$\sub$0/ to exclude the grating lobe. Measurement results show a gain 9.69 dB at broadside and 8.3 dB at the beam-tilt angle of 16$^{\circ}$ by imposing a progressive phase of 90$^{\circ}$.

• Journal of the Korean Institute of Telematics and Electronics
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• v.20 no.3
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• pp.40-44
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• 1983

A wide band quasi-log periodic microstrip antenna is designed using circular-disc microstrip patches as a basic radiator. The radiating elements are series-fed by a coplanar feeding network which consists of an open circuited feed line with a branch line connected to each radiating element. Experiment results show that the values of VSWR are less than 2.3 over the range of 2.72-3.43 GHz.