• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.4 no.1
• /
• pp.67-76
• /
• 2000

In this paper, a low noise amplifier has been developed, which is operating at L-band i.e., 1525-1575 MHz. By using resistive decoupling circuits, the resistor dissipates undesired signal in low frequency band. By adopting this design method the stability of the LNA is increased and the input impedance matching is improved. The LNA consists of the low noise GaAs FET ATF-10136 and the internally matched VNA-25. The low LNA is fabricated by both the RP circuit and the self-bias circuits in an aluminum housing. As a result, the characteristics of the LNA implemented show more than 32 dB in gain, lower than 0.5 dB in noise figure, 18.6 dBm output gain in 1 dB gain compression point.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.23 no.4
• /
• pp.137-142
• /
• 2023

When designing a SMPS(Switched Mode Power Supply) circuit, a part that is easily overlooked without special consideration is a snubber circuit. However, the performance degradation of the SMPS due to the snubber circuit and the effect on the entire SET cannot be ignored. In addition, a snubber circuit is added to both ends of the switch to protect the device from peak voltage and current during switching and to reduce loss during on/off switching. Therefore, in this paper, for a sufficient understanding of snubber circuits, theoretical analysis and experimental formulas that can be applied by designers during actual circuit design are arranged to promote optimization of snubber circuits.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.2
• /
• pp.319-324
• /
• 2012

This paper introduces a 2-dimensional touch screen panel driver based on an improved capacitive sensing circuit. The improved capacitive sensing circuit based on charge pump can eliminate the remaining charges of the intermediate nodes, which may cause output voltage drift. The touch screen panel driver with mixed-mode circuits was built and simulated using Cadence Spectre. Verilog-A models the digital circuits effectively and enables them to interface with analog circuits easily. From the simulation results, we can verify the reliable operations of the simple structured touch screen panel driver based on the improved capacitive sensing circuit offering no voltage drift.

• Journal of the Korean Institute of Telematics and Electronics C
• /
• v.36C no.1
• /
• pp.12-21
• /
• 1999

All kinds of electronic machinery including portable communication system are being smaller size and are used at high frequency. It generates a lot of unwanted noise signals called electromagnetic interface (EMI). This paper presents an analysis result of EMI generation in VLSI and propose new circuits to minimize of EMI using I/O driver with parallel buffer architecture and distributed decoupling capacitor in a chip. The proposed circuits are evaluated with i8052 MCU which is shown reducing of delta current 1/3 times and improvement of EMI more 10dBuV compared with conventional processors.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.15 no.2
• /
• pp.168-176
• /
• 2015

Due to the reduction in device feature size, transient faults (soft errors) in logic circuits induced by radiations increase dramatically. Many researches have been done in modeling and analyzing the susceptibility of sequential circuit elements caused by soft errors. However, to the best knowledge of the authors, there is no work which has well considerated the feedback characteristics and the multiple clock cycles of sequential circuits. In this paper, we present a new method for evaluating the susceptibility of sequential circuit elements to soft errors. The proposed method uses four Error Propagation Probability Matrixs (EPPMs) to represent the error propagation probability of logic gates and flip-flops in current clock cycle. Based on the predefined matrix union operations, the susceptibility of circuit elements in multiple clock cycles can be evaluated. Experimental results on ISCAS'89 benchmark circuits show that our method is more accurate and efficient than previous methods.

• Journal of the Korean Society for Railway
• /
• v.20 no.5
• /
• pp.602-611
• /
• 2017

In railway systems, the exchange of information between running trains and wayside equipment is a very important role in various applications such as position detection and train control. Track circuits have been used as the medium for information transmission between trains and wayside. However, track circuits must be installed continuously along the track on the ground, resulting in an inevitable increase in installation and maintenance costs. One of the most promising solutions to reduce these costs is to mix continuous information transmission (via wireless communication) and discontinuous information transmission (via transponder). In this study, we designed antennas of railway high-speed transponder readers and tags for wireless power transmission, which can be used to transmit information from ground to high-speed trains with a maximum speed of 400km/h. We also verified system performance through computational simulation and prototyping.

• Journal of Microbiology
• /
• v.38 no.3
• /
• pp.117-121
• /
• 2000

Recent advances in studies of bacterial gene expression and light microscopy show that cell-to cell communication and communication and community behavior are the rule rather than the exception. One type of cell-cell communication, quorum sensing in Gram-negative bacteria involves acyl-homoserine lactone signals. This type of quorum sension represents a dedicated communication system that enables a given species to sense when it has reached a critical population density. and to respond by activating expression of specific genes. The LuxR and LuxI proteins of Vibrio fisheri are the founding members of the acyl-homoserine lactone quorum sensing signal receptor and signal generator families of proteins. Acyl-homeserine lactone signaling in Pseudomonas aeruginosa is one model for the relationship between quorum sensing community behavior, and virulence. In the P. aeruginosa model. quorum sensing is required for normal biofilm maturation and virulence. There are multiple quorum-sensing circuits that control the expression of dozens of specific genes in P. aeruginosa.

• Proceedings of the KIEE Conference
• /
• 2005.11a
• /
• pp.44-47
• /
• 2005

This paper presents the efficient plan for the EMI improvement from of TFT-LCD Module. It investigates the frequency characteristics of Power/Ground Plane of TFT-LCD drive circuit PCB concretely. After the frequency characteristics is reviewed, EMI improvement is tried to insert to RC termination between Power/Ground Plane and to shift resonance frequency. It is confirmed by a simulation result and RC Termination which is inserted the point where the resonance characteristics change is necessary. It applied in 19 "SXGA TFT-LCD drive circuits and the EMI improvement verification is described.

• Proceedings of the KIPE Conference
• /
• 2014.07a
• /
• pp.530-531
• /
• 2014

본 논문에서는 자기유도결합 무선전력전송 (IPT) 시스템의 Bifurcation 현상에 대한 분석을 통해, 1, 2차 보상회로 별 Bifurcation 현상 발생 임계점을 도출한다. 도출된 임계점에 해당하는 파라미터를 근거로 400W급 SP 보상회로 IPT 시스템에 대한 PSIM 시뮬레이션을 통하여 분석의 타당성을 검증한다.

• Current Optics and Photonics
• /
• v.6 no.1
• /
• pp.15-22
• /
• 2022

This paper describes the construction of a phase shifter with low loss and small volume. To construct it, we use the two graphene layers that are separated by a hexagonal boron nitride (hBN) and embedded in a silicon waveguide. The refractive index of the waveguide is adjusted by applying a bias voltage to the graphene sheet to create an optical phase shift. This waveguide is a compact device that only has a radius of 5 ㎛. It has a phase shift of 6π. In addition, the extinction ratio (ER) is 11.6 dB and the insertion loss (IL) is 0.031 dB. Due to its unique characteristics, this device has great potential in silicon on-chip optical interconnection and all-optical multiple-input multiple-output processing.