Emission on a frequency or frequencies which are outside the necessary bandwidth and the level of which may be reduced without affecting the corresponding transmission of information. Spurious emissions include harmonic emissions, parasitic emissions, intermodulation products and frequency conversion products, but exclude out-of-band emissions. [NTIA] [RR]

Circuit noise or interference that is like a signal. [T1.401-1988]

Any unintentional emission.

In radio reception, a response in the receiver intermediate frequency (IF) stage produced by an undesired emission in which the fundamental frequency (or harmonics above the fundamental frequency) of the undesired emission mixes with the fundamental or harmonic of the receiver local oscillator.

Any tone that (a) is other than a fundamental tone or its harmonics, and (b) is generated within the back-to-back connected transmit and receive terminal or channel units, when the fundamental, i.e., a test sine wave, is applied to the transmit terminal or channel unit input. [After T1.305-1990]

Abbreviation for structured query language. The international standard language for defining and accessing relational databases. [Bahorsky]

Service Quality Management

A pixel of equal width and height; i.e., having an aspect ratio of 1:1
Note: Pixels created by computer graphics usually have an aspect ratio of 1:
1. Television technology was not always concerned with pixel aspect ratio. However, modern dependence upon digital electronic post-production (e.g., image distortion, rotation, or size changes) has underscored the advantages of square pixels, which… (Read More →)

A wave that has two significant conditions, i.e., two levels of amplitude, that change from one condition to the other in a relatively short time compared to the wavelength.
Note: When the instantaneous amplitude is plotted versus time or distance, the waveform has a rectangular shape. [From Weik '89]

See cybersquatting.