• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.550-554
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• 2003

In order to detect very short electromagnetic pulses (EMP) with picosecond width, a receiving antenna with a wide bandwidth and good sensitivity over several GHz is needed. In this paper, the receiving characteristics of various thin wire monopole (or dipole) antennas with nonreflecting resistive loading are analyzed for determining the optimum configurations. This study also indicates that it is possible to choose an ideal load impedance for achieving the required fidelity and sensitivity. The analysis is facilitated by introducing the frequency transfer function.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1159-1164
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• 2006

Broadband antennas have late-time ringing by multi-reflections between feed points and 0pen ends of the antennas, which indicates the narrowband nature of the antenna. The resistive loading has been used to reduce the late time ringing that is important for ground penetrating radar and resonance detection systems in order to prevent masking of target. In this paper, we design an ultra wide band antenna with resistive loading technique to reduce the internal reflections within the antenna.. The designed antenna is implemented and tested to show inIproved characteristics.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.6
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• pp.1111-1116
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• 2007

Antennas of the near field detection radar require little distortion in time domain caused by multi reflections between feed and open ends of the antenna, so that help to discriminate the target signal from the clutters. The resistive loading techniques have been used to reduce the late time distortions in order to prevent masking of target. In this paper, we design a microstrip antenna with two arms having sloted lines, which have inductance loading effect. Implemented antenna shows better performance on reducing late-time ringing, and the peak value of the received signal becomes 45% greater than the one by the antenna with two non-sloted lines.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.3
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• pp.19-26
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• 1999

The detectability of pipes buried in dry sand is investigated by using the GPR with self-designed bow-tie antenna. The antennas are covered with shielding structures to reduce the direct-coupling between the transmitting and receiving antennas. The ringing, due to finite length of the antenna, is decreased by performing resistive termination at the ends of the antennas. It is shown that without additional signal processing, the presence of various buried targets can be found by discriminating hyperbolic pattern in B-scan data.

• Transactions on Electrical and Electronic Materials
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• v.17 no.5
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• pp.257-260
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• 2016

In this paper, two configurations (T-type and Y-type) of dual band Wilkinson Power Divider based upon Hilbert curves are presented. Formerly, the concept of Hilbert Curves was implemented in only designing microstrip antennas. In power dividers, this is the very first attempt of incorporating them for size reduction. In addition to this, an effect of inculcation of high-dielectric constant layer (Hafnium-oxide, HfO₂, ε_r= 25) between a substrate and top metallization in both configurations was investigated. The proposed configurations are designed on a high resistive silicon substrate (HRS) for L and S bands with resonating frequencies of 1.575 and 3.4 GHz. Both configurations have return loss that is better than 20 dB and an insertion loss of around 6 dB; isolation better than 30 dB was achieved for both models.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.6 no.1
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• pp.3-9
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• 1995

An isotropic electric-field probe, capable of characterizing and quantifying electromagnetic field, was fabricated. The probe consists of three short dipole antennas, a beam-lead Schottky diode and the high resistive transmission line. In order to get the isotropic response three mutually orthogonal dipoles are configured to form the probe. The probe's short dipole elements allow measurements of electric fields from 300MHz to 2GHz with a flatness of .+-. 2.9dB. The mutually orthogonal dipole configration shows a .+-. 1.2dB deviation in the isotropic response with respect to angle.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.3
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• pp.454-463
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• 2000

A method is presented to alter the geometry of the conventional linearly shaped wire antenna for increasing its bandwidth. The synthesis is two-demensionally symmetric and is based on the minimization of frequency-dependence of the boresight far-field electric field intensity. The current distribution on the wire is calculated by Galerkin method using pulse functions. The shaping limitation for wide-band characteristics is still found because of standing waves due to reflected waves from antenna ends. The limitation overcome by a distribution of resistive loads near ends of wire. The antenna loaded resistively has flat characteristics satisfying a power gain of $6.5\pm1.1$dBi and VSWR of at most 2 over 10:1 bandwidth. The results are verified by comparing with similar results for the conventional linear V-dipole.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.4
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• pp.261-268
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• 2017

In this paper, we propose an FSSH(Folded Slot Spherical Helix) magnetic dipole antenna with a form factor easy to build and study its radiation properties. The number of folded arms, the gap between them and the metal thickness are tuned to achieve relatively simple structure to realize whereas maintaining high radiation efficiency at an electrically small size. The proposed design shows wide radiation efficiency bandwidth and it is confirmed by circuit simulation that the non-Foster impedance matching techniques could be utilized for its practical use. The prototype of the proposed antenna is built with the aid of an SLS(Selective Laser Sintering) 3D printing technology. The measured result shows lower Q impedance characteristic due to high resistive loss of the copper tape joints.