continuous wave


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Related to continuous wave: Continuous wave radar, continuous wave laser, continuous wave Doppler

continuous wave

[kən¦tin·yə·wəs ′wāv]
(electromagnetism)
A radio or radar wave whose successive sinusoidal oscillations are identical under steady-state conditions. Abbreviated CW. Also known as type A wave.

continuous wave

(communications)
(CW) A term from early radio history, when the spark gap method of transmission was replaced by vacuum-tube oscillators. A spark gap initiates a ringing, damped sinusoidal wave in a tuned circuit consisting of an inductor and capacitor. The energy in this circuit is constantly changing between the capacitor's electrostatic field and the inductor's magnetic field. The energy is then coupled, loosely (so as not to dampen the wave too quickly), to the radiating antenna.

In contrast, a vacuum-tube oscillator constantly adds energy to the tuned circuit, compensating for the amount coupled to the antenna, and the transmitted energy or "wave," is therefore "continuous".

Many (especially radio amateurs) continue to understand "CW" to mean transmission by means a signal of a single frequency which is either on or off (e.g. Morse code), as opposed to a carrier which varies continuously in amplitude, frequency or phase. Some would even call the former "unmodulated" even though turning on and off is actually an extreme form of amplitude modulation.
References in periodicals archive ?
The continuous wave based laser diodes are being deployed for material processing, telecommunications, storage devices, laser pointers, etc.
Permeability of the blood-brain barrier induced by 915 MHz electromagnetic radiation, continuous wave and modulated at 8, 16, 50, 200 Hz.
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2] laser with a continuous wave output power of 20 watts is sufficient to create contrasting lines on many of these materials.
To produce light as a continuous wave instead of as brief pulses, researchers must find ways of reducing the voltage needed to drive the device.
Soraa has demonstrated more than 2 watts from a blue laser diode, and more than 4 watts from a blue laser array with continuous wave power in multi spatial mode and multi spectral mode.
Continuous Wave Based Laser Diodes Market is Set to Grow at 16% CAGR Till 2018, Says TechSci Research Report 'Global Continuous Wave Laser Diode Market Forecast and Opportunities, 2018' ( http://www.
The topics include acoustic antennas for biomedical and industrial ultrasonic imaging, terahertz broadband micro-antennas for continuous wave imaging, the airborne high precision location of radiating sources, and the co-design of antennas with low noise amplifier for ultra-wideband applications.
They explain introductory concepts and basic experimental techniques; useful variants such as continuous wave, phase shift, and broadband CRDS; and developments and applications such as in analytical and atmospheric chemistry, combustion studies, spectroscopic studies of transient molecules in astrophysics, the analysis of exhaled breath in clinical diagnostics, and CRDS under extreme conditions, the detection of species in plasmas and flames.
The tests were the world's first live firings with the Interrupted Continuous Wave Illumination (ICWI) class missiles; the ESSM and SM2 block III.
The MRL700 delivers consistent, precision measurement, based on frequency modulated continuous wave technology for a price that is normally associated with pulsed technology instruments.

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