• Korea Petroleum Association Journal
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• s.281
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• pp.53-56
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• 2011

• 프린팅코리아
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• s.63
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• pp.80-81
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• 2007

• 베이커리
• /
• no.2 s.355
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• pp.96-96
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• 1998

• 베이커리
• /
• no.11 s.364
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• pp.159-159
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• 1998

• 베이커리
• /
• no.12 s.341
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• pp.104-105
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• 1996

• 베이커리
• /
• no.10 s.447
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• pp.137-137
• /
• 2005

• 대한한약
• /
• s.2
• /
• pp.335-335
• /
• 1998

• 베이커리
• /
• no.11 s.340
• /
• pp.100-101
• /
• 1996

• The KIPS Transactions:PartC
• /
• v.13C no.6 s.109
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• pp.677-684
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• 2006

This paper investigates the link margin of MB-OFDM UWB system quantitatively. Various simulations are performed considering the implementation loss by imperfect synchronization unit and the effect of multi-path fading channels. MB-OFDM UWB system uses ZP(Zero Padding) instead of CP(Cyclic Prefix) and supports two transmission modes; one is TFI(Time Frequency Interleaving) mode that transmits OFDM symbols using different carrier frequency from symbol to symbol according to Time Frequency(TF) codes, the other is FFI(Fixed Frequency Interleaving) mode that transmits OFDM symbols using a specific carrier frequency. The advantage of if and TFI is to be able to increase the transmitting power effectively compared to the existed OFDM systems that transmit the signal continuously at the same average transmitting power. From the analysis results of Ink margin, to guarantee the service range of 4m in 200Mbps mode, TFI mode must necessarily be implemented and the service range of 480Mbps mode is estimated about 1-2m in the line-of-sight multi-path channel (CMI).

• Journal of IKEEE
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• v.1 no.1 s.1
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• pp.11-18
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• 1997

By utilizing the technique to monitor the DC cell node voltages through circuit simulation, degradation of the static read operating margin In high load-resistor SRAM cell was examined, which is caused by parasitic resistances and transistor asymmetries in this cell structure. By selectively adding the parasitic resistances to an ideal cell, the influence of each parasitic resistance on the operating margin was examined, and then the cases with parasitic resistances in pairs were also examined. By selectively changing the channel width of cell transistors to generate cell asymmetry, the influence of cell asymmetry on the operating margin was also examined. Analyses on the operating margins were performed by comparing the supply voltage values at which two cell node voltages merge to a single value and the differences of cell node voltages at VDD=5V in the simulated node voltage characteristics. By determining the parasitic resistances and the transistor asymmetries which give the most serious effect on the static read-operation of SRAM cell from this analysis based on circuit simulated, a criteria was provided, which can be referred in the design of new SRAM cell structures.