Quantum and Evolution Series Installation and Operating Handbook
7-194
7.4.16 Fetching Web Pages from a Remote Modem
When a framed service is selected, it is possible to use the ESC channel to fetch web
pages from a remote modem, thereby allowing M&C control of the remote modem via the
normal web interface.
Because the ESC channel is low rate, the modem implements this feature in a very
efficient manner. Instead of fetching each entire web page, the local modem sends
commands over the ESC channel to fetch the required data, which it then populates into
a locally generated web page before sending this onto to the web browser. The selection
of Local or Remote mode is made through the toggle switch on the right hand top corner
of each web page as shown below.
Local/Remote Modem Web Interface Toggle Switch
7.4.17 Adaptive Signal Pre-distorter
This feature, which is controlled from the web user interface, enables 16QAM
constellations to be adaptively predistorted to counter the effects of AM-AM and AM-PM
nonlinear distortion in the communications path (i.e. transponder and/or HPA).
Predistortion has two major advantages:
•
It allows 16QAM to be used in some links where only QPSK or 8PSK was feasible
before, thereby saving bandwidth
•
It allows the back-off level of the uplink HPA to be reduced, thereby liberating more
power into the uplink or alternatively allowing a lower power HPA to be used.
