• Journal of electromagnetic engineering and science
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• v.14 no.3
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• pp.306-313
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• 2014

A Fabry-Perot resonator cavity antenna for Ku-band application is presented in this paper. The Fabry-Perot cavity is formed by a ground plane and a frequency selective surface (FSS) made of a circular hole array. The cavity resonance is excited by a single-feed microstrip patch located inside the cavity. The measured results show that the proposed antenna has an impedance bandwidth of approximately 13% ($VSWR{\leq}2$) and a 3-dB gain bandwidth of approximately 7%. The antenna produces a maximum gain of 18.5 dBi and good radiation patterns over the entire 3-dB gain bandwidth. The antenna's very thin profile, high directivity, and single excitation feed make it promising for use in wireless and satellite communication applications in a Ku-band frequency.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.2
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• pp.50-55
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• 2012

Fabry-Perot (FP) resonator antennas with scan capabilities are described in this paper. The proposed antennas, excited by a thinned array, not only achieve higher directivities but also improve suppression of sidelobes relative to that of the thin array alone. Compared to the conventional microstrip patch array, the directivity enhancement and suppression of sidelobe level were achieved by increase of the aperture size of the proposed Fabry-Perot resonator antenna.

• Electrical & Electronic Materials
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• v.13 no.9
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• pp.13-17
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• 2000

• Current Optics and Photonics
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• v.2 no.5
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• pp.395-399
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• 2018

This article investigates the mechanism of electronic signal phase noise degradation induced by laser phase noise in optical links comprising optical resonators. Through theoretical derivation, we find that the phase noise of the output electronic signal has the same spectral shape of optical intensity noise as the output of the optical resonator. We propose that the optical resonator transfers laser phase noise to light intensity fluctuation and then the intensity fluctuation is converted to electric phase noise through AM-PM conversion mechanism in the photodiode. An optical link comprising a Fabry-Perot resonator was constructed to verify the proposed mechanism. The experimental results agree with our theoretical prediction verifying that the supposition is correct.

• Journal of the Optical Society of Korea
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• v.2 no.1
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• pp.30-33
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• 1998

We present the analysis of phase-shifted fiber Bragg gratings by coupled-mode equations. The transmission is expressed as that of a Fabry-Perot resonator with complex reflectance and complex transmittance. The transmission spectrum, the effective cavity length, and the behaviors with different phase-shifts are investigated. A very flattered transmission peak is obtained by introducing three phase-shifts in a grating.

• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.239-240
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• 2009

• Current Optics and Photonics
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• v.2 no.5
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• pp.448-452
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• 2018

A three-wavelength $Pr^{3+}:YLF$ laser at 604 nm, 607 nm and 640 nm simultaneously output by Fabry-Perot (F-P) etalon has been obtained. A 444 nm blue laser diode is used for pumping the $Pr^{3+}:YLF$ crystal, and a 0.1 mm F-P etalon is inserted in the resonator to select wavelength. The theoretical model of three-wavelength $Pr^{3+}:YLF$ laser is established, by adjusting the tilt angle of the etalon, the transmittances of the different wavelengths can be controlled, and the threshold values can be made to equalize by controlling the loss among different wavelengths. In the experiment, when the tilt angle of etalon is $9^{\circ}$ and the optimized length of resonator is 48 mm, the total output power of 25 mW at the three-wavelength is achieved at incident pump power of 7.5 W.

• Journal of the Korean Institute of Telematics and Electronics
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• v.3 no.4
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• pp.16-24
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• 1966

The LASER Amplifier is treated in the manner of a Fabry-Perot Resonator with an active media, five layers are considered: air, reflector, active medium(ruby), reflector and air. One dimensional scalar wave equations are derived using the method of boundary value probrems in which it is assumed that incident coherent radiation falls normally on the surface wall. All equations are treated from the transient analysis point of view using the Laplace transform nethods, and are arranged steady state region as an amplifier and transient region as a self excited oscillator. Also some remarks are given on the design problem of LASER amplifier in connection with the transient terms involved.

• Korean Journal of Optics and Photonics
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• v.1 no.2
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• pp.178-184
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• 1990

The fiber laser was fabricated using Nd doped single mode fiber. The fiber was made by MCVD and solution doping method, and the Fabry-Perot resonator was composed with two dichroic mirrors. It was operated at 1.096 um with 15 nm bandwidth. When the reflectivity of the output copuling mirror was 67.5%. the maxiurn output power 1.88 mw and its slope efficiency 1.28%. was obtained.

• Korean Journal of Optics and Photonics
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• v.5 no.3
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• pp.394-403
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• 1994

Chaos characteristics of laser diodes with external optical feedback is investigated. For a FabryPerot resonator laser, optical feedback by external mirror is assumed. The simulation is performed in such a way that a current of $1.3J_{th}$ is injected into the $1.3{\mu}m$wavelength "InGaAsP" buried hetero structure laser. With the increment of K, the system shows the evolution of four steps as follows: i) When the optical feedback coefficient K is very small, the relaxation oscillation is damped and the system reaches the steady state showing the stable operation characteristics. ii) As K increases a little bit, the relaxation oscillation is not damped any more and the system begins to maintain the periodic oscillation. iii) When K is increased further, the oscillation shows the larger amplitude and the long periodic length. iv) When K is increased very large, the system gets unstable and enters into the coherejlce collapse state. state.