Spectrum analyzer

About: Spectrum analyzer is a research topic. Over the lifetime, 12217 publications have been published within this topic receiving 101851 citations.

Method of monitoring placement of voltage/current probes on motors

Abstract: A motor performance analyzer senses currents and voltages applied to the motor, converts the sensed signals to digital data signals, and stores the digital data signals. The analyzer includes a processor for evaluating and comparing the digital data signals to predetermined values for voltage and current of the motor to determine and check for the correct placement of the current and voltage probes along corresponding phases of the motor. The analyzer also includes [and] a display for alerting a user or technician to potential motor problems, or to developing problems, including winding faults and broken rotor bars. [Advanced signal processing techniques are used to further evaluate stored data and to provide trending information.]

High Voltage-Cylinder Sector Analyzer 300/15: A cylindrical sector analyzer for electron kinetic energies up to 15 keV

Abstract: We have developed an energy analyzer, High Voltage-Cylinder Sector Analyzer 300/15, for electron kinetic energies up to 15 keV. It is especially suited for hard x-ray photoelectron spectroscopy, but also for ultraviolet and soft x-ray photoelectron spectroscopy (ultraviolet photoemission spectroscopy, x-ray photoemission spectroscopy), Auger electron spectroscopy, and reflection high energy electron spectroscopy. The analyzer is based on a cylinder sector with 90 degrees deflection, 300 mm slit-to-slit distance, and a four-element pre-retarding lens system with 50 mm sample-to-lens distance. The result is a very compact design of the analyzer that is easily integrated into a multipurpose experiment with different techniques. A low noise/low drift electronics is capable of continuous energy scans from 0 to 15 keV using nonlinear lens curves. The first analyzer is allocated at the Spanish CRG SpLine beamline at the ESRF at an end station where simultaneous surface x-ray diffraction is possible. The analyzer is operated routinely since 2006 up to 15 keV electron kinetic energy, expanding the achievable electron kinetic energy range compared to other commercial analyzers. In this work we present a detailed description of the developed electron analyzer. The analyzer capabilities, in terms of energy resolution and transmission, are shown by using an electron gun, an ultraviolet-discharge lamp, and hard x-ray synchrotron radiation as excitation sources.

Spectrum opportunities for electromagnetic energy harvesting from 350 mhz to 3 ghz

Abstract: This paper presents spectrum opportunities for radio frequency (RF) energy harvesting identified through power density measurements from 350 MHz to 3 GHz. The field trials have been performed in two different cities (Covilha and Lisbon), by using the NARDA-SMR spectrum analyser with measuring antenna, and the Signal Hound spectrum analysers, respectively. The scope of our research considers RF energy harvesting devices, enabling to convert RF energy to direct current (DC), providing an alternative source to power supply wireless sensor network (WSN) devices. Printed antennas, able to operate at GSM (900/1800) bands, are proposed with gains of the order of 1.8-2.06 dBi and efficiency 77.6-84%. Guidelines for the choice of textile materials for a wearable antenna are also provided.

Radiation measuring device

Abstract: A radiation measuring device comprising a radiation detector for detecting radiation quantum arriving in the Poisson distribution, a phase height analyzer for analyzing a height of an output signal from the detector to extract signal components at a level within a predetermined level, converter for integrating an output signal from the detector to produce pulses of which the number corresponds to the integrated value, a switch for selecting the output signal from the analyzer when the number of arrival photons is smaller than a predetermined value and for selecting the output signal from the converter when the number of photons is larger than the predetermined value and a counter for counting output pulses of the selected analyzer or counter.

Insulation bonding test system

Abstract: A method and a system for testing the bonding of foam insulation (22) attached to metal. The system involves the use of an impacter (10) which has a calibrated load cell (12) mounted on a plunger (14) and a hammer head (16) mounted on the end of the plunger (14). When the impacter (10) strikes the insulation (22) at a point to be tested, the load cell (12) measures the force of the impact and the precise time interval during which the hammer head (16) is in contact with the insulation (22). This information is transmitted as an electrical signal (20) to a load cell amplifier (28) where the signal (20) is conditioned and then transmitted to a Fast Fourier Transform (FFT) analyzer (34). The FFT analyzer (34) produces energy spectral density curves (power plotted against frequency in Hertz) which are displayed on a video screen (39). An operator, by observing the frequency point at which the curve terminates, may determine the quality of the bond. Specifically, the termination frequency of the energy spectral density curve may be compared with a predetermined empirical scale to determine whether a high quality bond, good bond, or debond is present at the point of impact. For future reference and use, data from the FFT analyzer (34) are recorded on a magnetic disk (41) and/or a hard copy is produced by a printer (43).