Bandwidth (signal processing)Bandwidth is the difference between the upper and lower frequencies in a continuous band of frequencies. It is typically measured in unit of hertz (symbol Hz). It may refer more specifically to two subcategories: Passband bandwidth is the difference between the upper and lower cutoff frequencies of, for example, a band-pass filter, a communication channel, or a signal spectrum.
Spectral widthIn telecommunications, spectral width is the width of a spectral band, i.e., the range of wavelengths or frequencies over which the magnitude of all spectral components is significant, i.e., equal to or greater than a specified fraction of the largest magnitude. In fiber-optic communication applications, the usual method of specifying spectral width is the full width at half maximum (FWHM).
Pulse (signal processing)A pulse in signal processing is a rapid, transient change in the amplitude of a signal from a baseline value to a higher or lower value, followed by a rapid return to the baseline value. Pulse shapesPulse shapes can arise out of a process called pulse shaping. Optimum pulse shape depends on the application. Rectangular pulseThese can be found in pulse waves, square waves, boxcar functions, and rectangular functions.
Signal processingSignal processing is an electrical engineering subfield that focuses on analyzing, modifying and synthesizing signals, such as sound, images, potential fields, seismic signals, altimetry processing, and scientific measurements. Signal processing techniques are used to optimize transmissions, digital storage efficiency, correcting distorted signals, improve subjective video quality, and to detect or pinpoint components of interest in a measured signal.
Cutoff frequencyIn physics and electrical engineering, a cutoff frequency, corner frequency, or break frequency is a boundary in a system's frequency response at which energy flowing through the system begins to be reduced (attenuated or reflected) rather than passing through.
Beam diameterThe beam diameter or beam width of an electromagnetic beam is the diameter along any specified line that is perpendicular to the beam axis and intersects it. Since beams typically do not have sharp edges, the diameter can be defined in many different ways. Five definitions of the beam width are in common use: D4σ, 10/90 or 20/80 knife-edge, 1/e, FWHM, and D86.
Dependent and independent variablesA variable is considered dependent if it depends on (or is hypothesized to depend on) an independent variable. Dependent variables are the outcome of the test they depend on, by some law or rule (e.g., by a mathematical function). Independent variables, on the other hand, are not seen as depending on any other variable in the scope of the experiment in question. Rather, they are controlled by the experimenter.
SpectrometerA spectrometer () is a scientific instrument used to separate and measure spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomenon where the spectral components are somehow mixed. In visible light a spectrometer can separate white light and measure individual narrow bands of color, called a spectrum.
DecibelThe decibel (symbol: dB) is a relative unit of measurement equal to one tenth of a bel (B). It expresses the ratio of two values of a power or root-power quantity on a logarithmic scale. Two signals whose levels differ by one decibel have a power ratio of 10 (approximately 1.26) or root-power ratio of 10 (approximately 1.12). The strict original usage above only expresses a relative change.
Optical communicationOptical communication or optical telecommunication (sometimes known as optical transmission), is communication at a distance using light to carry information. Optical communication can be performed visually or by using electronic devices. The earliest basic forms of optical communication date back several millennia, while the earliest electrical device created to do so was the photophone, invented in 1880.
TimeContinuous progression from past to futureNot to be confused with Thyme.Time is the continuous progression of existence that occurs in an apparently irreversible succession from the past, through the present, and into the future.*As an Amazon Associate I earn from qualifying purchases.