Wavecom W40PC, Руководство пользователя

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Advanced Topics WAVECOM Decoders v6.15 W40PC, W41PC, W51PC
The measurement is started by selecting a bandwidth. The display of the frequency spectrum
has a linear scale and covers a dynamic range of 60 dB. The internal dynamic range is
considerably higher due to the 16 bit A/D converter used, but the configured display resolution
has proved better in practical use.
The frame refreshment frequency averages 10 to 20 pictures per second, allowing even fast
signal changes to be displayed. The frame refreshment frequency is however dependent on the
CPU power of the PC and its video system.
To start the Real-Time-FFT click on the FFT button or use "
Analysis/Real-time FFT
" from
the HF or VHF modes menus.
To select a display bandwidth use "
Demodulator/Bandwidth
" or double-click on the
"
Bandwidth:
" field on the Demodulator Status Bar. Real-time bandwidths of 0.5, 1.0, 4.0
and 24 kHz are available.
The W51PC also supports " BW 2 kHz ", " BW 48 kHz ", " BW 96kHz ".
To activate the measurement cursors , click inside the FFT graphics window. The left and
right cursors may be moved around using the mouse. The cursor positions are displayed as
absolute frequency values. The center cursor automatically displays the center value.
To remove the cursors click on the graphics window again.
When the cursors have been placed in the desired positions they may all be moved right or left
by moving the center cursor. The measurement of frequency spacing in MFSK and FDM
systems is hence significantly facilitated.