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SATEL OY
// SATELLAR MANUAL // RADIO UNIT // USER GUIDE // V. 1.8
5. Interfaces
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QAM-radio supports trellis coding with 8-, 16-, 32- and 64-QAM modulations which does not increase sym-
bol rate nor expand the bandwith. However it can introduce coding gain and thus improve the S/N ratio
compared to uncoded system. Trellis coding has effect on latency and it can be disabled if the low latency
is the primary concern. Trellis coding is enable by default.
5.3 DC supply
The DC connector of the RU is a detachable / lockable screw terminal. The DC voltage range is 10.6-30
V. The power supply used should be able to deliver at least 17.9 W of DC power. Please note that the RU
delivers DC power to the entire stack of SATELLAR units. So when using the RU together with CU the power
consumption of the entire stack must be taken into account when selecting the DC power supply.
5.4 Diagnostics, monitoring, changing settings
The settings of the RU can be viewed and changed by SATEL NETCO Design stack. The computer is then
connected to the serial connector of the RU and the connector must be configured to accept NMS mes-
sages. If the basic radio settings have previously been set locally it is also possible to establish a remote
connection to another RU and change and view the settings of that modem over-the-air.
When the RU operates together with the CU with a display and a keypad, the device settings can be
viewed and changed via the graphical user interface of the CU. Alternatively; the Web interface can be
used.
TD
RD
PWR
STAT
RX
TX
CTS
RTS
USB
ETH
PWR
STAT
OK
SA00008
Figure 5.4 RU together with Central Unit (CU) equipped with LCD display and keypad, the main views
