Tektronix NetTek YBT250, Руководство пользователя

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Glossary
Glossary- 2
YBT250 Field Transmitter & Interference Tester User Manual
Difference. Difference is the power difference between Channel
Power and the Ref Power.
Error Vector Magnitude (EVM). Error Vector Magnitude is the RMS
value of all the vectors that extend from the ideal constellation
points to the received signal constellation points in a record of
demodulated CDMA symbols, divided by the RMS value of the
signal. This result is multiplied by 100 to give a final value in
percent.
Flash Memory. Flash memory is a form of non-volatile memory.
When the YBT250 software is stored in flash memory, the
YBT250 loads more quickly at power on.
FM Deviation. FM Deviation is the maximum one-sided frequency
deviation of the carrier due to modulation. The measurement
displays whichever is greatest of either the positive or negative
deviation.
Forward Frequency. The frequency the base station uses to transmit to
the mobile unit. Also called Downlink Frequency.
Frequency Marker. The frequency marker indicates the Measurement
Frequency setting. The Measurement Frequency is the frequency
at which measurements are made. The frequency marker
appears on the display as a small triangle at the bottom of a
trace display and a circle on the trace itself. Changing the
frequency marker location, by tapping a new location on the
display or entering a new Channel number or frequency, changes
the Measurement Frequency.
Frequency Error. Frequency Error is the difference in frequency
between the measured frequency of the selected channel and the
frequency assigned to the channel in the channel table.
JPEG -- Graphics File Format. JPEG, an acronym for Joint Photograph-
ic Experts Group, is one of the file formats available for saving
screen captures. Files saved in JPEG format can be much
smaller in size than files saved in BMP format. The filename
extension is “jpg”.