• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.4
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• pp.38-48
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• 2011

Block based LCD backlight nonideality and crosstalk compensation methodologies are proposed based on the analysis of backlight profiles and image pixel homogeneity. Large computation complexity required in the conventional compensations is minimized without the degradation of image qualities by optimizing image block size, image area inside the block to be excluded from the compensation computation and the required backlight range to be computed. The optimization results of computation complexity as well as image qualities are verified for the proposed compensation by real image data simulations.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.11
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• pp.1374-1382
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• 1995

In TFT-LCDs, as the display size area becomes larger, and the resolution higher, we have to consider the image degradation effects due to the incorporation of the TFT-LCD parameters such as the data-line resistance, the common electrode resistance, the data-line to common parasitic capacitance, and the output characteristics of driver ICs. One of the degradation effects is crosstalk resulting from the coupling between the source bus-line and common electrode. Since a source signal which represents a large number of display data is supposed to vary frequently, the common signal level is affected through the coupling effect, resulting in the degradation of nearby pixel drive signals. Therefore, we proposed a method to compensate for this source-common electrode coupling effect, we also designed and experimented the feasibility of our crosstalk compensation circuit in the actual TFT-LCD. We saw that the newly designed compensation circuit greatly reduced the crosstalk in display pattern image.

• Proceedings of the KIEE Conference
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• 2000.11c
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• pp.449-451
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• 2000

Crosstalk is the primary cause of image distortion in active matrix liquid crystal displays (AMLCD). Crosstalk produces voltage errors that limit gray scale fidelity and consequently, degrades display resolution, contrast ratio, color fidelity, and image quality. In this study, crosstalk phenomena of some methods to compensate level shift voltages has been simulated. This will be contributed to find the way to design the excellent image quality of the TFT-LCDs.

• Journal of IKEEE
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• v.23 no.3
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• pp.1046-1053
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• 2019

In a multi-channel single-ended system, the far-end crosstalk (FEXT) due to mutual inductance and mutual capacitance between two adjacent channels critically limit the bandwidth. FEXT causes crosstalk-induced jitter (CIJ) and crosstalk-induced glitch (CIG) which leads to timing margin and voltage margin degradations, respectively. Therefore, FEXT must be compensated in order to increase eye opening and achieve high data-rate. It can be compensated in transmitter by controlling the timing of the data or reshaping the waveform of the signal. Also, FEXT can be compensated in receiver by generating mimicked FEXT using high-pass filter. In this paper, recent techniques to compensate FEXT are investigated, with discussions of their pros and cons.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1316-1318
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• 2009

Nonideality of LED lens and diffuser as well as crosstalk between backlights should be compensated because they have large effects on image qualities. The computation complexities of conventional compensations are greatly increased as resolution becomes higher. The block based compensation is proposed to alleviate the computation complexity considering backlight profiles and image pixel characteristics.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.10
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• pp.22-28
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• 1998

Signal transmission and crosstalk of coupled bondwires buried in plastic packages are analyzed using the Method of Moments and the Fourier Transform algorithm. It is also shown that the quasi-static crosstalk model of SPICE is inappropriate for designing the high-speed plastic packages. Plastic packaging material, increasing the self and mutual capacitances, is found to be helpful for the signal transmission integrity due to the dielectric compensation effect. However, it is also observed that the plastic material increases the crosstalk due to the radiation-enhanced mutual coupling effect. By investigating the geometrical and material dependence of the pulse transmission and crosstalk, it is found that the radiation-enhanced coupling effect is significant for most of typical bondwire geometries and plastic package materials. These calculation results can be effectively used for designing plastic packages of high-speed digital IC's and monolithic RFIC's.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.3
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• pp.232-239
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• 2010

By using the clock timing control at transmitter (TX), the crosstalk-induced jitter (CIJ) is compensated for in the 2-bit parallel data transmission through the coupled microstrip lines on printed circuit board (PCB). Compared to the authors' prior work, the delay block circuit is simplified by combining a delay block with a minimal number of stages and a 3-to-1 multiplexer. The delay block generates three clock signals with different delays corresponding to the channel delay of three different signal modes. The 3-to-1 multiplexer selects one of the three clock signals for TX timing depending on the signal mode. The TX is implemented by using a $0.18\;{\mu}m$ CMOS process. The measurement shows that the TX reduces the RX jitters by about 38 ps at the data rates from 2.6 Gbps to 3.8 Gbps. Compared to the authors' prior work, the amount of RX Jitter reduction increases from 28 ps to 38 ps by using the improved implementation.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.4
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• pp.52-58
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• 2007

The irregular fuel surface was observed by the visualization of hybrid rocket combustion. Even though the test condition maintained oxidizer rich environment, the irregular dark fuel surface was formed as the result of incomplete combustion. In order to investigate the correlation of the characteristics of oxidizer flow and the irregular fuel surface, various flow conditions were imposed such as swirl flow, induced swirl flow by helical fuel configuration and straight flow. Test results revealed no correlation was found between oxidizer flow condition and irregular fuel surface. And this can be a commonly observed phenomena in the tests with different fuel/oxidizer combination. Thus, the irregular fuel surface can be a result of the interaction of blowing flow of vaporized fuel and the boundary layer of oxidizer flow. A further study will be required to confirm the assumption for the formation of irregular fuel surface.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.8A
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• pp.697-704
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• 2005

In this paper, Passive Temperature Compensation Technology is apply to 8-channel Optical multiplexer with 1000Hz channel spacing. The 8-channel multiplexer is fabricated by connecting three cascaded Mach Zehnder Interferometer(MZI) of optical fiber type, and each interferometer has the wavelength interval of 100GHz, 2000Hz and 4000Hz, respectively. Furthermore, to acquire uniform insertion loss, it is fabricated by using Wavelength Flatten Coupler(WFC) in which the variation of insertion loss is low. $CO_2$ laser to adjust precisely the wavelength. The optical fiber is very sensitive in the thermal variation around. Thus, When fabrication the prototype, it is applied a technique to compensate the optical thermal effect because the center wavelength at the output is shifted according to the thermal variation around. In summary, The prototype composed by eight cascaded MZI has an insertion loss of 5.5 dB, the bandwidth of 0.8nm at 0.5 dB point, and channel crosstalk of 25 dB. Furthermore, the loss dependent on polarization is measured as 0.06dB. Consequently, the output wavelength is shifted within 0.05 m when the surrounding temperature varies until $60^{\circ}C$

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.7
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• pp.716-725
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• 2002

In this paper, we showed the applicability of power symmetric MSSI(Mid-Span Spectral Inversion) to the long-haul WDM system with the channel interference due to FWM(Four Wave Mixing). And we showed the degree of performance improvement. We used 1 dB EOP(Eye-Opening Penalty) criterion so as to evaluate the degree of compensation dependent on the variation of chirp parameter of optical pulse for the various input power in high speed tansmission system. And we evaluated the maximum input power of channel be able to be the signal to crosstalk noise (SNR) above 20 dB in the transmission link with the channel interference due to FWM. Consequently the proposed MSSI compensation method is capable to transmitting the total 68 WDM channels simultaneously with a 0.4 nm channel spacing and 5.3 dBm maximum input power in a 10 Gbps transmission link. Therefore the proposed power symmetric MSSI compensation method may be very useful for the implementation of long-haul wideband WDM transmission systems with relatively high power and improved performance.