• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1995.10a
• /
• pp.813-817
• /
• 1995

Structural analysis of horizontal cold chamber die casting machine is performed by the FEM. The analyzed model is made up of stationary die platen,movable die platen,link housing platen, C-frame, and tie bar which mainly undertake die locking force and injection force. In modeling, compression gap elements are used for to simulate contacting condition between tie bar and movable die platen, movable die platen and base frame, and link housing and base frame. Unbalanced die locking force imposed on four tie bars are considered. As the results, the deformed shape and the stresses of the die casting machine are given.

• Korean Journal of Optics and Photonics
• /
• v.21 no.2
• /
• pp.74-81
• /
• 2010

A modeling methodology for the analysis of injection-locked Fabry-Perot laser diodes (FP-LDs), promising for cost-effective WDM-PON sources, is proposed. The time-domain large-signal model that is used is found to provide quite similar results to some experimental ones. With our methodology, we model characteristics of FP-LDs, such as influence of reflectivity at a facet and detuning on injection-locking. The eye diagram characteristics are also investigated. It is observed that the facet reflectivity at the injection side should be lower than 1% to provide stable operation in terms of good side-mode suppression ratio and independence from detuning between narrow-band injection noise and LD modes. It is also observed that good eye opening can be obtained for 155 Mbps modulation while the parameters such as the active region thickness should be properly optimized to obtain reasonable eye opening at 1.25 Gbps.

• Current Optics and Photonics
• /
• v.5 no.4
• /
• pp.384-390
• /
• 2021

This paper presents a wide-range tunable wavelength-locking technology based on optoelectronic oscillation (OEO) loops for optical fiber sensors and microwave photonics applications, explains the theoretical fundamentals of the design, and demonstrates a method for locking the relative wavelength differences between a leader semiconductor laser and its follower lasers. The input of the OEO loop in the proposed scheme (the relative wavelength difference) determines the radio-frequency (RF) signal frequency of the oscillation output, which is quantized into an injection current signal for feedback to control the wavelength drift of follower lasers so that they follow the wavelength change of the leader laser. The results from a 10-hour continuous experiment in a field environment show that the wavelength-locking accuracy reached ±0.38 GHz with an Allan deviation of 6.1 pm over 2 hours, and the wavelength jitter between the leader and follower lasers was suppressed within 0.01 nm, even though the test equipment was not isolated from vibrations and the temperature was not controlled. Moreover, the tunable range of wavelength locking was maintained from 10 to 17 nm for nonideal electrical devices with limited bandwidth.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.9 no.4
• /
• pp.811-815
• /
• 2005

We theoretically studied synchronization of chaotic oscillation in semiconductor lasers with chaotic light injection feed-back induced chaotic light generated from a master semiconductor laser was injected into a solitary slave semiconductor laser. The slave laser subsequently exhibited synchronized chaotic output for a wide parameter range with strong injection and frequency detuning within the injection locking scheme. We also analytically examined chaos synchronization based on a linear stability analysis from the view point of synchronization based on a linear stability analysis from the view point of modulation response of injection locked semiconductor lasers to chaotic light signal.

• Proceedings of the Optical Society of Korea Conference
• /
• 2007.07a
• /
• pp.9-10
• /
• 2007

• Proceedings of the Optical Society of Korea Conference
• /
• 2001.08a
• /
• pp.188-189
• /
• 2001

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.22 no.5
• /
• pp.522-527
• /
• 2011

In this work, a 54 GHz divide-by-3 injection-locked frequency divider(ILFD) based on ring oscillator has been developed in a 0.13-${\mu}M$ Si RFCMOS technology for phase-locked loop(PLL) application. The free-running frequency is 18.92~19.31 GHz with tuning range of 0~1.8 V, consuming 70 mW with a 1.8 V supply voltage. At 0 dBm input power, the locking range is 1.02 GHz(54.82~55.84 GHz) and, with varactor tuning of 0~1.8 V, the total operating range is 2.4 GHz(54.82~57.17 GHz). The fabricated circuit size is 0.42 mm${\times}$0.6 mm including probing pads and 0.099 mm${\times}$0.056 mm for core area.

• Current Optics and Photonics
• /
• v.2 no.1
• /
• pp.27-33
• /
• 2018

We report the physical implementation of a tunable photonic microwave delay line filter based on injection locking of a single Fabry-Perot laser diode (FP-LD) to a reflective semiconductor optical amplifier (RSOA). The laser generates equally spaced multiple wavelengths and a single tapped-delay line can be obtained with a dispersive single mode fiber. The filter frequency response depends on the wavelength spacing and can be tuned by the temperature of the FP-LD varying lasing wavelength. For amplitude control of the wavelengths, we use gain saturation of the RSOA and the offset between the peak wavelengths of the FP-LD and the RSOA to decrease the amplitude difference in the wavelengths. From the temperature change of total $15^{\circ}C$, the filter, consisting of four flat wavelengths and two wavelengths with slightly lower amplitudes on both sides, has shown tunability of about 390 MHz.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.27 no.8
• /
• pp.717-724
• /
• 2016

This paper presents design of a 40 GHz CMOS PLL frequency synthesizer for a 60 GHz sliding-IF RF transceiver. For stable locking over a wide bandwith for a injection-locked frequency divider, an inductive-peaking technique is employed so that it ensures the PLL can safely lock across the very wide tuning range of the VCO. Also, Injection-locked type LC-buffer with low-phase noise and low-power consumption is added in between the VCO and ILFD so that it can block any undesirable interaction and performance degradation between VCO and ILFD. The PLL is designed in 65 nm CMOS precess. It covers from 37.9 to 45.3 GHz of the output frequency. and its power consumption is 74 mA from 1.2 V power supply.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.11 no.3
• /
• pp.190-197
• /
• 2011

This paper presents a 144 GHz divide-by-2 injection locked frequency divider (ILFD) with inductive feedback developed in a commercial 90-nm Si RFCMOS technology. It was demonstrated that division-by-2 operation is achieved with input power down to -12 dBm, with measured locking range of 0.96 GHz (144.18 - 145.14 GHz) at input power of -3 dBm. To the authors' best knowledge, this is the highest operation frequency for ILFD based on a 90-nm CMOS technology. From supply voltage of 1.8 V, the circuit draws 5.7 mA including both core and buffer. The fabricated chip occupies 0.54 mm ${\times}$ 0.69 mm including the DC and RF pads.