• Journal of the Optical Society of Korea
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• v.8 no.3
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• pp.99-103
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• 2004

This paper describes the optimal design of an AWG spectrum to meet various specifications and improve some physical parameters. The objective function is the norm of the difference between design parameters and target values. To obtain the design parameters, the Fourier model is employed and the design variables arc spacing of array waveguide, width of array waveguide, optical path difference, and focal length. The (1+1) Evolution Strategy is employed as the optimization tool. The optimization procedure is applied to a 16-channel AWG and the optimized design variables will considerably improve the system performance.

• Journal of Electrical Engineering and Technology
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• v.4 no.2
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• pp.287-291
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• 2009

In this paper, an optical switch/modulator is designed and its light propagating characteristics analyzed using a simplified BPM. The distinctive feature of this switch/modulator is that all its waveguide branches are designed as single-mode. The principle of the device is based on the coupled mode theory in the Y-junction interconnecting waveguide. In spite of the fact all waveguides are designed as single-mode, by adjusting the interconnecting waveguide length'of the device the same characteristics as existing up to date devices are obtainable. Numerical results show that the switching characteristics periodically depend upon an interconnecting waveguide length with a spatial of about $150^{{\mu}m}$ in the $Ti:LiNbO_3$ step index waveguide. The design concept would therefore be utilized effectively in fabricating a monolithic high density optical integrated circuit.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.4
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• pp.29-34
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• 2023

A clear and efficient design method for a microstrip-to-waveguide inline transition, which is based on an analytical model, is presented. The transition consists of three parts: a microstrip-to-SIW transition, a dielectric-loaded waveguide with substrate-height, and a stepped-height waveguide. The shape of the transitional structure is formed for impedance matching. Two equivalent type0s of dielectric-loaded transitional structures are proposed. The design method is applicable to any size of the waveguide, but a design method of two Ka-band transitions is demonstrated. The proposed transitions, in a back-to-back configuration, have less than 1.2 dB insertion loss and more than 15 dB return loss from 29.8 GHz to 38.2 GHz.

• The Journal of Korea Robotics Society
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• v.16 no.1
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• pp.1-11
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• 2021

Soft robotics has attracted a huge amount of interest in the recent decade or so, be it either actuators or sensors. Recently, a soft optical waveguide sensor has proven its effectiveness for various sensing applications such as strain, force, and bending measurements. The operation principle of the waveguide is simple, but the present technology is far too much complex to manufacture the waveguide. The waveguide fails to attract various practical applications in comparison to other types of sensors despite its superior safety and ease working principle. This study pursues to develop the soft sensors based on the optical phenomena so that the waveguide can be easily manufactured and its design can be conducted. Several physical properties of the waveguide are confirmed through the repetitive experiments in the aspects of strain, force, and bending of the waveguide. Finally, the waveguide sensor is embedded inside the actuator to verify the effectiveness of the proposed waveguide as well as to extend the application fields of the waveguide sensor.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.87-90
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• 2000

In this paper. we present a method for a systematic design of a dielectric slab polarizer in the circular waveguide. This structure is realized using a tapered dielectric slab inside a circular waveguide. Commercial software is used to obtain the equivalent dielectric constant of the circular waveguide partially filled with a dielectric slab. The length of the tapered region is determined so that the reflection from the dielectric slab is sufficiently low. A polarizer operating at 10 GHz band is designed, fabricated and tested.

• Journal of the Optical Society of Korea
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• v.14 no.3
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• pp.277-281
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• 2010

We propose a design and optimization method for a dielectric-loaded surface plasmon polariton waveguide using a genetic algorithm. This structure consists of a polymer ridge on top of two layers of substrate and gold film. The thickness, width and refractive index of the ridge are designed to optimize the figures of merit including mode confinement and propagation length. The modal analysis combined with the effective index method shows that the designed waveguide exhibits a fundamental propagation mode with high mode confinement while ensuring that the propagation loss remains relatively low.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.7 no.3
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• pp.246-253
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• 1996

In this paper, a problem that occurred in the telegraphist equation established by mode conversion method is solved as analysis tapered transmission line is applied to a waveguide taper. After comparing and analyzing the taper function with variant properties, we select on of taper functions not only that is easily designed but also that have good properties. And then we propose the applicant method to design the waveguide taper and deal with the design of mode transducer between rectangular waveguide and circular waveguide. The measured results of scattering coefficients for the mode transducer fabricated with designed data are agreed well with the theoretical results and the validity of the proposed design and analysis method has been confirmed.

• Proceedings of the IEEK Conference
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• 2002.06a
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• pp.455-458
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• 2002

Design methods are presented for an X-band traveling-wave slot array realized on a rectangular waveguide. An array of 21 longitudinal slots is realized on the broad wall of a rectangular waveguide. The squint of the antenna main beam is adjusted using the element spacing and the waveguide broad wall dimension. The excitation of the array is controlled by the slot offset from the waveguide center line Multiple I-plane steps are placed around last slot elements so that the second-order beam due to tile reflected wave Is minimized A waveguide-to-coaxial adapter Is designed for feeding the array antenna from a coaxial system. Results of the design show an outstanding performance of the antenna 17.1 dB gain. 36"beam 1111, and -21 dB maximum sidelobe level.evel.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.143-146
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• 2000

This paper presents a study on design for the k-junction of a feeder waveguide with an inductive wall using FDTD method. The feed structure consists of a single waveguide plated on the same layer as radiating waveguide and is characterized by the unit divider, railed a $\pi$-Junction. This $\pi$-Junction with an inductive wall splits part of the power into two branch waveguide through one coupling window, and can excite densely arrayed waveguide at equal phase and amplitude. The power dividing characteristics of a $\pi$ -Junction obtained by FDTD method are compared with one of Galerkin's method of moments. The scattering matrices a $\pi$ -junction calculated by FDTD method are realized.

• ETRI Journal
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• v.34 no.4
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• pp.621-624
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• 2012

A new miniaturized 4-port waveguide generating a transverse electromagnetic wave is proposed. The waveguide presents enhanced performance of higher field uniformity in extended test volume up to an increased test frequency limit compared to that of the conventional 2-port waveguide. The advantageous features of the proposed waveguide have been obtained through a new design scheme based on effective miniaturization maintaining good impedance matching. Consequently, we can provide a more accurate electromagnetic compatibility test method, covering larger devices operating in higher frequencies, which is a marked improvement upon the conventional approaches.