Due to interference between co-located wireless networks, obtaining accurate channel assessment becomes increasingly important for wireless network configuration. This information is used, among others, for cognitive radio solutions and for intelligent channel selection in wireless networks. Solutions such as spectrum analyzers are capable of scanning a wide spectrum range, but are not dedicate...

1. Introduction Testing is an important part of design and production of integrated circuits. Such testing of proper function of the circuits consumes a lot of time and resources. It is necessary to set and evaluate lots of parameters in analog testing. It is very inefficient in manual implementation. This testing can be speeded up by using automatic measurements. Professional testing equipment...

Adam Watts Department of Physics, University of Illinois at Urbana-Champaign ABSTRACT With the goal of investigating the effects of hand-in-bell playing of the French Horn, a technique was developed to quickly and accurately measure the input impedance of the instrument to determine intonation and playability of resonant modes. This technique is a continuation of previous work done by Professor...

The paper theoretically describes Polarization Mode Dispersion (PMD) which is important parameter in high-speed optical networks. Furthermore, compensation methods and measurement principles are presented. Main attention is given to Fixed Analyzer (FA) method that uses common research laboratory equipment in setup. We performed practical measurement of the PMD by using Optical Spectrum Analyzer...

A system for measuring the absolute spectral responsivity of solar cells is described. The system uses higher-powered LED arrays that are coupled to an optical light guide that together provide large area illumination. Two different measurement methods were developed and tested using this measurement apparatus. The first method is an individual LED lock-in technique that can be performed over a...

|We introduce the generalized evolutionary spectrum (GES) as a family of time-varying power spectra for nonstationary random processes. The GES extends the well-known evolutionary spectrum and the recently de ned transitory evolutionary spectrum. A particularly interesting member of the GES family is the novel Weyl spectrum. We discuss the properties of the Weyl spectrum, and we apply the Weyl ...

Cognitive radio is a new concept of reusing licensed spectrum in an unlicensed manner. The motivation for cognitive radio is various measurements of spectrum utilization, that generally show unused resources in frequency, time and space. These ”spectrum holes” could be exploited by cognitive radios. Some studies suggest that the spectrum is extremely underutilized, and that these spectrum holes...

Capacitive accelerometers with electrostatic force feedback are widely employed, because of performance and robustness. The force feedback acts as a means for electronic modulation of the spring constant of the suspension. Commonly, the electrostatic feedback is employed for null-based acceleration measurement. A suitable electrostatic time-varying actuation could instead be used to make the ac...

High-pulse-energy supercontinuum radiation with a width exceeding 900 nm in the near-infrared spectral region has been generated in conventional single-mode fibre. The fibre was pumped at 1064 nm which is in the normal dispersion regime, resulting in predominantly red-shifted spectral broadening. Supercontinuum pulse energies exceeding 450 nJ were obtained. The use of conventional fibre allows ...

A general technique for the periodic orbit quantization of systems with near-integrable to mixed regular chaotic dynamics is introduced. A small set of periodic orbits is sufficient for the construction of the semiclassical recurrence function up to, in principle, infinite length. As in our recent work the recurrence signal is inverted by means of a high resolution spectral analyzer (harmonic i...