Turbo trellis-coded modulation (T-TCM) is one of several techniques for combining turbo codes with multilevel modulation in order to save the bandwidth of the transmission systems. T-TCM was shown to perform very well...
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Turbo trellis-coded modulation (T-TCM) is one of several techniques for combining turbo codes with multilevel modulation in order to save the bandwidth of the transmission systems. T-TCM was shown to perform very well on AWGN channels, but its performance over frequency-selective fading channels is unknown. In this paper, a system model to investigate the performance of T-TCM schemes over frequency-selective fading channels is proposed. Simulation results show that when an appropriate receiver is available, T-TCM also performs well on frequency-selective fading channels. T-TCM performance is much better than any other coded-modulation scheme for this type of channel.
In this article, we have studied the role of photoeffects in the formation of aluminum back surface field (BSF) contacts on p-type silicon wafers by using different lamp configurations in rapid thermal processing (RTP...
In this article, we have studied the role of photoeffects in the formation of aluminum back surface field (BSF) contacts on p-type silicon wafers by using different lamp configurations in rapid thermal processing (RTP). Use of photons of wavelengths less than 800 nm in conjunction with infrared and visible photons in RTP resulted in the reduction of processing time from 202 to 138 s and the processing temperature from 890 to 850 °C. The reduction in the overall thermal budget used for BSF contact formation is a direct result of photon assisted RTP. The availability of a large number of high energy photons on the metal surface also resulted in improved electrical, structural and mechanical properties of the processed device.
The complexity of analog VLSI systems is often limited by the number of pins on a chip rather than by the die area. Currently, many analog parameters and biases are stored off chip. Moving parameter storage on chip co...
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The complexity of analog VLSI systems is often limited by the number of pins on a chip rather than by the die area. Currently, many analog parameters and biases are stored off chip. Moving parameter storage on chip could save pins and allow us to create complex programmable analog systems. In this paper, we present a design for an on-chip non-volatile analog memory cell that can be configured in addressable arrays and programmed easily. We use floating-gate MOS transistors to store charge, and we use the processes of tunneling and hot-electron injection to program values. We achieve greater than 13-bit precision with no crosstalk between memory cells.
We address the problem of efficient circuit switching in wide area networks. The solution provided is based on finding optimal routes for lightpaths and semilightpaths. A lightpath is a fully optical transmission path...
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We address the problem of efficient circuit switching in wide area networks. The solution provided is based on finding optimal routes for lightpaths and semilightpaths. A lightpath is a fully optical transmission path, while a semilightpath is a transmission path constructed by chaining several lightpaths together, using wavelength conversion at their junctions. The problem thus is to find an optimal lightpath/semilightpath in the network in terms of the cost of wavelength conversion and the cost of using the wavelengths on links. We first present fast, efficient algorithms both for the general problem and for a natural restricted version. The new algorithms outperform earlier work, providing time improvements amounting to an almost linear time factor in most cases. Also, all our algorithms can be implemented on the network in a distributed way.
We discuss applicability of several s-z transformations to digital simulation of seismic signal propagation. Starting from a digital simulator obtained by the conventional s-z transformation, we locally optimize it wi...
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We discuss applicability of several s-z transformations to digital simulation of seismic signal propagation. Starting from a digital simulator obtained by the conventional s-z transformation, we locally optimize it with respect to an error function defined on both time and frequency domain.
The concept of an optical fuzzy flip-flop, as an essential and basic component for the effective processing of fuzzy information, is introduced. A design based on the area-encoding technique and a multiple-imaging sys...
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The electrical characteristics of a glucose-sensitive polymeric hydrogel have been studied. The hydrogel matrices were prepared by radical polymerization of solutions containing 2-hydroxyethyl methacrylate, N,N-dimeth...
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The use of tungsten halogen lamps and the deuterium lamp as the source of thermal and optical energies has been exploited to deposit thin films of Ta2O5 on Si and conducting substrates, The leakage current densities a...
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The use of tungsten halogen lamps and the deuterium lamp as the source of thermal and optical energies has been exploited to deposit thin films of Ta2O5 on Si and conducting substrates, The leakage current densities are as low as 10(-10) A/cm(2) for gate voltage under 5V. Photons in visible, ultraviolet, and vacuum ultraviolet (lambda < 800 nm) regions provide higher bulk and surface diffusion coefficients as well as reduced activation energy for the chemical process involved in the chemical vapor deposition process. The low thermal mass of the substrate provides limited reaction processing capability. The photochemical and photophysical processes allow the participating atoms and molecules to adjust their bond geometries and occupy sites which result in overall reduction of stress and strain energy and provide materials with overall low microscopic defects at low processing temperature and with high throughput. New experimental results of Al-Ta2O5-Si3N4-poly Si-Al structure are presented. The leakage current-voltage characteristics are better than those reported by other researchers.
The concept of an optical fuzzy flip-flop, as an essential and basic component for the effective processing of fuzzy information, is introduced. A design based on the area-encoding technique and a multiple-imaging sys...
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The concept of an optical fuzzy flip-flop, as an essential and basic component for the effective processing of fuzzy information, is introduced. A design based on the area-encoding technique and a multiple-imaging system is proposed to implement two types of fuzzy J-K flip-flops. (C) John Wiley & Sons, Inc.
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