Revision: 1.0
DBS Nano PRO Transmitter User Guide
Copyright © 2022 Domo Tactical Communications (DTC) Limited. All rights reserved.
Commercial in Confidence
Page 5-19
Name
Description
Output attenuation
Attenuation can be applied to lower the RF output power.
Refer to
Section 7.1
for a dBm to Watts conversion table and example
calculation.
Linearity mode
High and ultra high linearity will improve COFDM performance at the
expense of power consumption. Usually used for improved adjacent
channel performance, or when working with power amplifiers which
must have excellent shoulder performance to operate.
Additional PA
When an external amplifier is used with the Nano PRO TX, the
amplifier rating can be matched but the system will need to be re-
calibrated. Please contact
Technical Support
.
Modulation scheme
Nano PRO TX uses DVB-T modulation.
5.4.2
DVB-T Settings
Name
Description
Dual pedestal
Dual Pedestal mode is an optional license feature that will double the
bitrate by using two adjacent COFDM channels, e.g., 8MHz in dual
pedestal mode will give a nominal bandwidth of 16MHz. See
Bandwidth
Higher bandwidths provide better data throughput but shorten range.
Constellation
QPSK
– less user data, more robust, more range.
16QAM
– more user data, less robust, less range (link performance
reduced by 5db).
64QAM
– max user data, least robust, least range.
FEC rate
The forward error correction (FEC) rate.
1/2
– 1 bit out of 2 bits is data and 1 bit is for error correction.
7/8
– 7 bits out of 8 bits are data and 1 bit is for error correction.
More user data means better picture quality, but less error correction
means less robust signal and thus less range.
Guard interval
The guard interval is an extension of the RF symbol period to give
immunity to reflections.
1/32
– deals with fast reflections. More data, less range.
1/4
– deals with slower reflections. Less data, more range.