ND SatCom SKYWAN IDU 7000, Manual

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2010-10-26 Network Design and Engineering Guide 71
General Carrier Design
From Capacity Estimation to TDMA Structure
The resulting user data rates for every carrier match the requirements which we have calculat-
ed with the capacity calculation sheet before.
The available Eb/No for a carrier is actually a quantity which can only be determined by a link
budget calculation procedure, which will be explained in the following section of this guide. Only
after that calculation the proper value for Eb/No can be inserted for each channel, leading to a
new selection of modulation and error correction factors. This change will hardly affect the user
data rate but will have a profound influence on the symbol rate and the required frequency
bandwidth.
The input and output values of the TDMA Calculator include many of the Sky WAN
®
IDU’s
TDMA master and network system parameters. Therefore the generated customer sheet is an
important input source for
the network commissioner.