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Comtech EF Data ROSS User Manual

Page 64

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ROSS

MN/13070

In the same manner, the up converter profile can also be altered to adjust frequency allocation
restrictions. This is useful when the ROSS unit performs a handoff from one satellite operating in
one band to another satellite operating in another band or even within the same satellite.

Normally this up converter section should remain unchecked as it does require extreme
caution when adjusting transmitting parameters.

Normally remains unchecked

TDM Reference Power is NOT
required, future usage.

However, this may be useful if up conversion restrictions are required in specific service areas,
e.g. vessels entering port and limited frequency band operations are enforced. If these conditional
areas are required, the operator may configure custom up converter settings to force the system
to limit the frequency range and center on very specific region of the pooled bandwidth.

Enabling and modifying converter settings places stored values within the selected Service Area
entry. As the service area is invoked, the Frequency Converter Profile is sent to VMS in the last
stage of a satellite handoff during modem registration process (see section 3.3.2 step 8). The new
configuration replaces the settings in VMS’s database for the down converter or up converter
assigned to the roaming remote modem. As previously stated, the updated converter
configuration ensures that the frequency calculations performed by VMS are correct with respect
to the actual satellite operating band.

5.18.1 Multiband LNB Support

Under multiband LNB operations it is important that this down converter Local Oscillator
frequency value matches that of the antenna controller value set in Optional Setting, (see section,
6.1.18). If a different LO is selected (used) other than the base set in the VMS database for the
site, it will be necessary to alter this value per service area to match.

Comtech EF Data, Vipersat Products

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