Specifications

UHP-1000 SATELLITE ROUTER
INSTALLATION AND OPERATION MANUAL, V. 2.5
(SW VERSION 2.5.X)
© ROMANTIS 2012 33 www.romantis.com
2.6 Burst demodulator
Burst demodulator router is purposed to receive collective TDMA satellite channels, sent by other routers.
This demodulator is used at the Central Station (Hub) for receiving Inroute (return) channels from network
terminals. One burst demodulator supports reception of single TDMA channel. The required number of Inroute
channels supported by Hub formed by cascading a respective number of satellite routers.
TDM/TDMA terminals with activated Mesh mode also use a burst demodulator to interact with other Hal Mesh
network terminals in one satellite hop and without transit via Hub. In this mode, the network may have any
topology (e.g. star of stars, partly meshed, fully meshed and etc.).
Also, the burst demodulator is used in HUBLESS TDMA networks for receiving a common collective network
carrier.
Satellite terminals with activated Burst Demodulator have to be equipped with PLL LNB convertors instead of low-
stable DRO LNB. Also, the link budget of such network has to ensure that TDMA carrier is properly received by all
network terminals with activated burst demodulator.
The burst demodulator is disabled in the basic configuration of the router. The respective software activation key
is necessary to enable the burst demodulator. Please refer to respective addendums to this manual for further
details about operations of the burst demodulator.
2.7 Modulator
UHP-1000 router modulator is designed to form carriers to transmit IP-packets and service information. The
modulator can operate in two basic modes – continuous (SCPC) when channel is transmitted in physical (but not
logical) DVB-S1 or DVB-S2 format and burst transmitting short (0.5 – 20 ms) bursts with information coded in the
generic protocol. Connected to the modulator output connector is a satellite transmitter (BUC) or via IF combiner
if BUC is shared by several systems.
The modulator can generate 10 MHz reference signal for the transmitter synchronization, and supply 24 VDC with
the current of up to 2 A. When switching such signals it essential that the following be taken into account:
10 MHZ REFERENCE SIGNAL SHOULD BE GENERATED ONLY BY ONE SOURCE IN THE CABLE SYSTEM. TWO SIGNAL ARE
SUPERIMPOSED THUS LEADING TO PERIODIC FADING AND HENCE TO COMMUNICATION FAILURES.
CABLE IMPEDANCE COMING TO TRANSMITTER CAN LEAD TO A HIGHER BUC CURRENT CONSUMPTION. BUC TRIES TO
CONSUME FIXED POWER AND IF PART OF THE VOLTAGE DROPS ACROSS THE CABLE, BUC WILL HAVE TO BE FED WITH
LOWER VOLTAGE AND WILL CONSUME HIGHER CURRENT. EXAMPLE: BUC CONSUMES 40 W. CURRENT THROUGH THE
SHORT CABLE IS 1.66 A. IF BUC IS CONNECTED VIA A 2-OHM RESISTANCE CABLE, THEN ACCORDING TO OHM’S LAW
(40/I) + (2*I) = 24, AND I=2 А (!). INEXPENSIVE CABLES FEATURE RESISTANCE PER UNIT LENGTH OF ABOUT 3 TO 4
OHM PER EVERY 100 M.
Table 8 Modulator parameters
Parameter
SCPC
Outroute/Hub
Remote
modulator frequency
User
user
auto
modulator symrate
User
user
auto
modulator FEC
User
user
auto
modulator inversion
User
user
user
modulator level
User
user
user
modulator tx
User
user
user
modulator power
User
user
user
modulator reference
User
user
user
modulator tlc mode
User
user
user
modulator tlc range
User
user
user