Tektronix 2715, Руководство пользователя

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Glossary
2715 User Manual
Glossary–7
MAX/MIN
A display mode on the spectrum analyzer that shows the maximum and
minimum signal levels at alternate frequency points; its advantage is its
resemblance to an analog display.
MIN HOLD
A spectrum analyzer feature which captures the minimum signal amplitude
at all displayed frequencies over a series of sweeps.
Modulate
To regulate or vary a characteristic of a signal.
Modulating Signal
The signal which modulates a carrier. The signal which varies or regulates
some characteristic of another signal.
Modulation
The process of varying some characteristic of a signal with a second signal.
Modulation Envelope
The curve limiting the carrier amplitude of an AM signal.
Multiple Display Memory
A digitally stored display having multiple memory sections which can be
displayed separately or simultaneously.
Noise
Unwanted random disturbances superimposed on a signal which tend to
obscure it.
Noise Floor
The self-noise of an instrument or system that represents the minimum limit
at which input signals can be observed. The spectrum analyzer noise floor
appears as a “grassy” baseline in the display, even when no signal is present.
Noise Sidebands
Undesired response caused by noise internal to the spectrum analyzer
appearing on the display around a desired response.
Nonvolatile RAM (NVRAM)
A type of random access memory (RAM) which does not lose its contents
when power is switched off.
Oscilloscope
An instrument for displaying a time domain representation of an electrical
signal; displays the amplitude of an input signal as a function of time.
Peak Detection
A detection scheme wherein the peak amplitude of a signal is measured and
displayed. In spectrum analysis, 20 log (peak) is often displayed.