• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.4
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• pp.661-668
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• 2012

A coaxial-cable impedance transformer that can be used in high power and wideband frequency range is an arbitrary impedance transformation ratio by an additional coaxial cable. The coaxial-cable impedance transformer to be 50-${\Omega}$ to 25-${\Omega}$ impedance transformation ratio is easily operated an wideband power divider by connecting two 50-${\Omega}$ lines at 25-${\Omega}$ impedance point. This wideband power divider has a poor output matching characteristic and a poor isolation characteristic between two output ports. In this paper, it proposes a coaxial-cable power divider to be a good output matching and isolation characteristics as it uses the singly terminated filter design theory. The odd-mode operation characteristic of the suggested power divider to use singly terminated low pass filter coefficient due to matching order and ripple value is examined by ADS program. And, it fabricates and measures the operation characteristic of 2-way power divider with 2nd-order and 4th-order matching circuit.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.3
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• pp.280-288
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• 2009

In this paper, a high-power and low-loss stripline 10-way power divider is designed and fabricated fur the feed network of an S-band linear array antenna with Chebyshev current distribution which has a narrow beam width and low side lobe level(SLL) of 35 dB or more. The unit cell of the power divider is based on a T-junction power divider and the whole divider is comprised of the cascaded unit cells. The multi-stage impedance transformer and modified ring hybrid are used in designing the power divider for performance improvement. And the reflection loss and insertion loss are improved by modifying a connector structure for a coaxial-to-stripline transition.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.14 no.6
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• pp.579-589
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• 1989

In this paper, planar power dividers/combiners for millimeter waves K-band or bands which can be printed on the substrates of hybrid or monolithic IC by surface mounting are designed and studied. Power dividers/combiners, and the conductor loss of microstrip lines in particualr the existing Wilkinson power dividers/combiners is modified ad amployes by ist equivalent circuit. Microwave CAD program SUPEROMPACT is employed for the Wilkinson power combiner which is modified and analyzed to reduce the high frequency coupling between the branches of the combiner, and the method to diminish the sensitivity of the input reflection of $2^n$-way power dividers/combiners is studied employing the commerical microwave CAD program package SUPERCOMPACT.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.4
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• pp.417-426
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• 2010

This paper describes the 6-way power divider to be used as a feeding structure of the waveguide array antenna generating the plane wave at the near distance. The SMA connector has been connected at the center of the power divider in order to feed the radiating element. The six output ports made of waveguide are positioned on the peripheral of the divider. This paper proposes the method utilizing the inductive post in order to decrease the return loss. The height of the feeding pin, the diameter of the inductive post, and the distance between the feeding pin and inductive post have been investigated, and as a result, the power divider has been optimized. The simulated and measured results show the low return loss of about -40 dB. The calculated and measured transmission coefficients are -7.78 dB and -8.06 dB, respectively. The output power of the six waveguide port show equal-amplitude and equal-phase distribution. Since the power divider proposed in this paper can be expanded to the divider having several output ports, it could be easily applied to the various array antennas.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.4
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• pp.499-508
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• 1993

This paper has dealt with the design methods and the analysis of frequency characteristics for the power splitters with ferrite toroids, which are extensively used in CATV and/or MATV systems. The theoretical design methods and frequency characteristics of the prototype Wilkinson's 2-way power divider have been reviewed in lumped-element circuits form. On the basis of the design theory of the prototype Wilkinson's power divider, the method compensating of the prototype Wilkinson's power divider has been proposed by means of adding matching transformers. Thus, it has been shown that the theoretical frequency characteristics of the compensated power splitter are improved drastically in comparison with the prototype Wilkinson's power divider. Furthermore, the practical measurements of the frequency characteristics for the fabricated circuits show agreements with the theoretical results, and hence, the validity of the proposed design and analysis methods has been confirmed.

• Journal of Advanced Navigation Technology
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• v.22 no.2
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• pp.141-147
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• 2018

We propose a wideband 4-way quadrature divider for global navigation satellite system (GNSS). The proposed divider consists of one balun and two 2-way quadrature dividers. In the balun, the input power is divided by a wilkinson divider and the out of phase characteristic is achieved by ${\pm}90^{\circ}$ metamaterial transmission line phase shifters applied two output ports. The structures of two quadrature dividers is similar to that of the balun, but the phase shifters of two output ports are exchanged by ${\pm}90^{\circ}$ metamaterial transmission line. Metamaterial transmission lines are designed by using five LC loaded transmission line (LCL-TL) unit cells. The fabricated 4 way quadrature divider has the phase characteristic of $90^{\circ}{\pm}10^{\circ}$ in 1.165 - 1.61 GHz.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.8
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• pp.721-728
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• 2009

Equal/unequal 4-way power divider suitable for satellite communication using SIW technology is presented in this paper. The control of positions of guiding posts provides equal or unequal power division ratios by maintaining the width of the SIW unchanged. In addition, the detailed descriptions for the proposed power divider include the general characteristics of radial waveguide, feeding part using coaxial cable, simple SIW structure, power-guiding posts, and transition for measurement. The comparison between the simulated and measured data shows a good agreement at a center frequency of 10 GHz. The measured input impedance bandwidths for equal and unequal power divisions are about 2.1 GHz and 3 GHz under the condition of less than VSWR 2:1, respectively.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.6
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• pp.1099-1104
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• 2007

A 1:6 Unequal 2-way Wilkinson power divider is proposed. The required microstrip line with $207{\Omega}$ characteristic impedance for 1:6 power divider is realized by adding defected ground structure (DGS) to the standard microstrip line. The adopted DGS has the rectangular geometry which results in the increased characteristic impedance. The rectangular-shaped DGS produces the transmission line having much higher characteristic impedance due to the increased equivalent inductance. The measured performances of the fabricated 1:6 power divider show the expected S-parameters with a good agreement with the predicted ones.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.10
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• pp.2339-2344
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• 2014

of a microstrip transmission line, this transmission line can operate as the microstrip line or the coplanar line according to open or short connection between the ungrounded copper plane and grounded plane on the base plane. Two different type operation of the transmission line means that one transmission line can have two different characteristic impedances. This paper proposes and fabricates the circuit to be operated 2-ports power transmission line or 2-way power divider with the stable input matching characteristic by using this dual-impedance transmission line. The proposed circuit operates 2-ports power transmission line in case of the coplanar line or 2-way power divider line in case of the microstrip line. The fabricated circuit shows $S_{21}$ > -0.2 dB and $S_{11}$ < -15 dB above 700 MHz when the circuit operates 2-ports power transmission line. And, it is $S_{21}$ > -3.8 dB, $S_{11}$ < -10 dB and $S_{21}/S_{31}$ < ${\pm}0.3dB$ above 700 MHz when the circuit operates 2-way power divider.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.6 no.1
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• pp.28-36
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• 1995

In this paper, a design method of multiple n-way low loss power divider for x-band is propossed. To decrease loss, only two-stages of transmission lines are used with isolation resistors for match. Ex- perimental results for 3-way and 4-way power dividers have the divided power of 5.54~6.17dB and 6.76~7.37 dB, the return loss of more than 17dB and 12dB, and the isolation of more than 18dB and 10dB at center frequency, respectively, The measured results show good agreement with the theoretical analysis.