• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.5
• /
• pp.967-973
• /
• 1997

In this paper, the designed and fabrication of a K-band push-push oscillator using miniaturized hairpin resonator have been presented. One experimenal oscillator has been designed and fabricated for K-band point-to-point operation. the miniaturized harpin resonator has been analyzed theoretically and simulated by MPIE(Mixed Potential Integral Equation) method. With this results, the analysis of hairpin resonator which coupled microstrip line has been carried out with transmission-mode using this results. an optimized output matching network for the suppression of the fundamental and the 3rd order harmonic was acquired by using a nonlinear analysis method. The fabricated oscillator shows the output power of -2.28dBm, the fundamental frequency suppression of -19dBc, the 3rd order harmonic suppressionof -24dBc and 0.33 percent effiiency at 22.8GHz. The experimental outputs are in good agreement with the theoretical and simulated results.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.5
• /
• pp.1114-1119
• /
• 2004

In this paper, we proposed that the synchronization and secure communication methods for build small world. In order to accomplish synchronization and secure communication in the small world, we used Chua’s oscillator which well represent the chaos dynamics and composed several stage with Chua’s oscillator by using coupled synchronization method. This paper shows a secure communication result in the small world network using coupled synchronizaton method.

• Korean Journal of Mathematics
• /
• v.26 no.4
• /
• pp.601-614
• /
• 2018

We consider the magnetic $Schr{\ddot{o}}dinger$ operator coupled with two different potentials. One of them is a harmonic oscillator and the other is a periodic potential. We give some periodic potential classes for which the operator has purely absolutely continuous spectrum. We also prove that for strong magnetic field or large coupling constant, there are open gaps in the spectrum and we give a lower bound on their number.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2002.11a
• /
• pp.389-393
• /
• 2002

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.1885-1890
• /
• 2003

In this paper, we have developed the voltage controlled crystal oscillator (VCXO) with positive emitter coupled logic(PECL). The VCXO is a crystal oscillator which includes a varactor diode and associated circuitry allowing the frequency to be changed by application of a voltage across that diode. The characteristics of the PECL has the delay time less than 2 ns and the faster logic gate, and the high level output greater than 2.3 V and the low level output smaller than 1.68 V.

• Journal of electromagnetic engineering and science
• /
• v.16 no.4
• /
• pp.229-231
• /
• 2016

A 180-GHz signal source based on a 65-nm CMOS technology has been developed in this study. The 180-GHz signal source consists of a 90-GHz fundamental-mode Colpitts oscillator and a 180-GHz frequency doubler. A coupled-line is employed to couple two oscillator cores for generating a differential signal, which is delivered to the input of the differential-mode doubler. The fabricated signal source operates from 181.2 to 182.4 GHz with output power varying from -15.3 to -10.8 dBm. The peak output power was -10.53 dBm at 181.3 GHz with a DC power consumption of 42 mW, and the associated phase noise was -71 dBc/Hz at 1 MHz offset.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.6 no.4
• /
• pp.20-30
• /
• 1969

Several new modulators using Voltage Variable Capacitance Diode are discribed. It was investigated that amplitude modulation which does not need modulation power is obtained by mdulation VVC diode as a tuning element of the quartz oscillator circuit. It offers a good AM system for carryphones in the citizen bands. While frequency modulated quartz oscillators coupled with a quarter wave network were tested as a wide band frequency modulator, Hartley type transistor oscillator offers the most stable and reproducibel FM quartz oscillator.

• Proceedings of the Optical Society of Korea Conference
• /
• 2001.02a
• /
• pp.248-249
• /
• 2001

A quantum-mechanical harmonic oscillator undergoes continuous amplitude fluctuation even in its ground state. This fluctuation, also known as the vacuum fluctuation, arises from the nonvanishing commutation .elation, [${\alpha}$, ${\alpha}$$\^$＋/] = 1, where ${\alpha}$(${\alpha}$$\^$＋/) is the annihilation (creation) operate. of the harmonic oscillator, One can make, however, the fluctuation of one quadrature amplitude decrease below the vacuum-state (or the coherent state) level at the cost of that of the other quadrature. (omitted)

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.14 no.1
• /
• pp.131-137
• /
• 2014

A 120 GHz voltage controlled oscillator (VCO) with a divider chain including an injection locked frequency divider (ILFD) and six static frequency dividers is demonstrated using 65-nm CMOS technology. The VCO is designed based on the LC cross-coupled push-push structure and operates around 120 GHz. The 60 GHz ILFD at the first stage of the frequency divider chain is based on a similar topology as the core of the VCO to ensure the frequency alignment between the two circuit blocks. The static divider chain is composed of D-flip flops, providing a 64 division ratio. The entire circuit consumes a DC power of 68.5 mW with the chip size of $1385{\times}835{\mu}m^2$.

• ETRI Journal
• /
• v.23 no.4
• /
• pp.199-201
• /
• 2001

The phase noise reduction in a configuration of the HEMT oscillator with a dielectric resonator coupled by a quarter-wavelength impedance inverter is investigated. Two HEMT oscillators for a satellite payload system are manufactured in the same configuration except for the coupling configuration of the dielectric resonator (DR) in order to empirically demonstrate the phase noise reduction. Experimental result shows that a phase noise reduction by 14 dB can be enhanced by increasing the characteristic impedance of a coupling microstrip impedance inverter.