ND SatCom SKYWAN IDU 7000, Manual

Page: 32 / 154

28 Network Design and Engineering Guide 2010-10-26
General Carrier Design
Essential SkyWAN
®
Satellite Link Layer Features
Figure 2-8 TDMA Frame Structure
Please note: a ranging slot is allocated only when a station is entering the network.
Transmit and Receive Carriers
Sky WAN
®
stations receive data on one or two carriers (e.g. IDU7000 with two demodulator
boards) . These carriers are defined by station configuration and are referred to as ’Home
Channel One’ and ’Home Channel Two’.
Sky WAN
®
stations can transmit data on any active carrier in the network (frequency or carrier
hopping). By configuration the possible transmit carriers can be allocated (restricted) for each
station.
A TDMA frame plan for a Sky WAN
®
network with 8 carriers is displayed in figure 2-9. In this
example carrier 1 and 2 carry a reference burst, carrier 3-8 only data bursts.
Figure 2-9 Tx Frequency Hopping
i
Restriction for master stations: Home Channel One must be carrier 1.
In Dual Uplink Beam (DUB) modes Home Channel Two must be carrier 2.