ATS-5X User Manual Page 43 of 44
5 Abbreviations
A way of expressing a ratio, typically a power ratio. A decibel
calculation for P
1
as compared to P
2
is shown below:
Ratios of quantities other than power are typically expressed in the
following manner:
Decibel with reference to 1
Milliwatt of power
A measure of power. When a device like the ATS-5X measures voltage
only, reference impedance is assumed, such as 600Ω. Power expressed
in dBm is calculated from the RMS voltage as follows:
Where Z
REF
is the reference impedance for the circuit.
Decibel above Reference Noise
A measure of power. Power expressed in dBrn is related to power
expressed in dBm as follows:
Decibel above Reference Noise
with C-message filter
The same dBrn except that the RMS voltage measurement for the dBm
calculation
Discrete Fourier Transform
A method of calculating a frequency spectrum from time domain data.
Dual Tone Multiple Frequency
Type of signaling digit that is composed of two simultaneous tones.
This is a popular type of communication standard (or device class) for
USB mouse and keyboard devices
A measure of frequency. A 1004 Hz tone is an oscillatory waveform
with a rate of 1004 repetitions per second
Inter-modulation Distortion
When multiple tones are present in a circuit, nonlinear distortion can
cause other tones at multiples of the base tones
A measure of frequency. 1 Kilohertz = 1,000 Hertz
A measure of electric current. 1 Milliampere = 10
-3
Ampere
A measure of time. 1 Millisecond = 10
-3
Second
The ratio between the peak value of a signal and its average. The ATS-
5X P/AR measurement performs this measurement on the absolute
value of the receive signal.
A measure of ratio. 1 ppm = 10
-6