Search results for "Width"
showing 10 items of 690 documents
Time dispersion characterization for UWB mobile radio channels between 3.1 and 10.6 GHz
2007
In this paper, a characterization of the UWB mobile radio channel time dispersion is presented. The results provided were obtained from a measurement campaign carried out in a typical indoor office scenario in the band from 3.1 to 10.6 GHz. Time dispersion metrics as delay spread, coherence bandwidth, delay interval and delay window, in both line-of-sight (LOS) and non-line-of-sight (NLOS) conditions are provided.
Optimization of dual-core and microstructure fiber geometries for dispersion compensation and large mode area
2009
We investigate dual concentric core and microstructure fiber geometries for dispersion compensation. Dispersion values as large as -59 000 ps/(nm km) are achieved, over a broad wavelength range with full width at half maximum exceeding 100 nm. The trade-off between large dispersion and mode area is studied. Geometries with an effective mode area of 30 microm2 and dispersion -19 000 ps/(nm km) and 80 microm2 with -1600 ps/(nm km) are proposed.
Random walks and random numbers from supercontinuum generation
2012
International audience; We report a numerical study showing how the random intensity and phase fluctuations across the bandwidth of a broadband optical supercontinuum can be interpreted in terms of the random processes of random walks and L´evy flights. We also describe how the intensity fluctuations can be applied to physical random number generation. We conclude that the optical supercontinuum provides a highly versatile means of studying and generating a wide class of random processes at optical wavelengths.
Algorithms on Graphs
1988
In this chapter we shall develop some basic algorithms for directed graphs and relations which will be of use in later chapters, where the efficient construction of parsers is considered. The constructions needed can be expressed as the computing of certain “relational expressions”. These are expressions whose operands are relations and whose operators are chosen from among multiplication, closure, union and inverse. For this purpose we need to develop an algorithm for computing the closure of a relation. In view of the nature of our applications, the most appropriate way to do this is by a depth-first traversal of the graph that corresponds to the given relation. Other ways of computing th…
New Multilevel Inverter Topology with Reduced Component Count
2019
This paper introduces a new topology of modular multilevel inverters, being suitable in medium and high voltage applications. As compared to the existing circuits, the proposed topology has advantages of high ‘levels/components’ ratio, increasing the output voltage levels without increasing the voltage stress across the used switches, structure simplicity, isolation features, and modularity. These merits allow it to fit well in high-reliability medium-power applications, which require fast troubleshooting and maintenance flexibility. Operating principles of the proposed scheme are detailed in low frequency and pulse width modulation. Simulation and experimental results validate the effectiv…
Dynamics at the Temperature Crossover in Dilute Polymer Solutions Investigated by Neutron Spin-Echo Spectroscopy
1980
Applying ultrahigh-resolution neutron spin-echo spectroscopy the existence of a $q$-dependent temperature crossover in the dynamics of dilute polymer solutions was proved. It is associated with the transition from $\ensuremath{\theta}$ to good solvent conditions. At small momentum transfers $q$ a nearly stepwise increase of the reduced quasielastic linewidth versus the reduced temperature was observed. With increasing $q$, both the sharpness of the transition and the step height decrease.
Ploidy levels in Citrus clementine affects leaf morphology, stomatal density and water content
2013
The objective of the present study was to understand the relationship among leaf morphology, stomatal characteristics and water relations in triploids generated through anther culture and their counterpart diploid plant of C. clementina. Triploid plants possessed small and narrow leaves as compared to diploid plant as evident by less leaf length, leaf width and leaf area. By contrast, the leaf index was observed to be more in triploids than haploid ones. Flow cytometric analysis re-confirmed the ploidy levels of heterozygous plant Hd as diploid and the ploidy of Th1, Th2, Th3 and Th4 plants as triploids. A positive relation was found between ploidy level and stomatal guard cell length and w…
Optical spectra beyond the amplifier bandwidth limitation in dispersion-managed mode-locked fiber lasers
2011
We investigate the intracavity pulse dynamics inside dispersionmanaged mode-locked fiber lasers, and show numerically that for a relatively wide range of parameters, pulse compression dynamics in the passive anomalous fiber can be accompanied by a significant enhancement of the spectral width by a factor close to 3. Varying the average cavity dispersion also reveals chaotic dynamics for certain dispersion ranges. The impact of the implementation of an optical output port to tap optimal pulse features is discussed. © 2011 Optical Society of America.
Real-time acquisition of wideband signals data using non-uniform sampling
2009
Wideband signal acquisition often faces a problem of bulk data recording. It is a critical factor in real-time systems. The paper discusses an approach that deals with this problem incorporating Digital Alias-free Signal Processing and Virtual Instrumentation technologies. Such combination is advantageous for real-time applications and useful in the development of measurement and software defined radio systems. Non-uniform sampling technique allows considerably decrease the data of wideband signals so, that they can be transferred in real-time to a typical PC through high-speed PCI Express communication interface. The experimental prototype system has been developed and obtained results are…
High power analysis and design of dual-mode channel filters
2009
In this paper, we present two dual-mode channel filter topologies which are able to withstand more than 600 W in Ku-Band. The two different designs (one with elliptical cavities and the other one with rectangular cavities) implement the same transfer function: four order, elliptical response centered in 12 GHz, with 40 MHz bandwidth and two transmission zeros. It is shown that the critical dimensions for the power-handling of these filters are the dimensions of the input-output irises. In fact, in order to rigorously obtain these conclusions and to reach these high-power levels (including margins), it is essential to use the advanced numerical techniques described in the paper to predict th…