1. DSNG SYSTEM
DIGITAL SATTELLITE NEWS GATHERING SYSTEM

2. WHAT IS DSNG?
• Satellite news gathering (SNG) is the use of
mobile communications equipment for the
purpose of worldwide news-casting. Mobile
units are usually vans equipped with
advanced, two-way audio and video
transmitters and receivers, using dish
antennas that can be aimed at geostationary
satellites.

3. Cont….
• A modern DSNG van is a sophisticated affair,
capable of deployment practically anywhere
in the civilized world. Signals are beamed
between a geostationary satellite and the van,
and between the satellite and a control room
run by a broadcast station or network.

4. TYPES OF DSNG IN
AIR NETWORK
• MOBILE DSNG SYSTEM
Equipments are mounted
within a vehicle.
• FLYAWAY DSNG SYSTEM
Equipments are mounted
within carry away
suitcases.

5. LEFT UPCON-
DIGITAL DIGITAL SSPA
ENCODER VERTER
Audio (1+1) MODULATOR (1+1) 100 W
RIGHT (1+1) (1+1)
(Stereo)
1.2 M
from OB spot LEFT Dish
Analog
Antenna
Audio
DIGITAL Power LNBC
RECEIVER
(Stereo) Divider (1+1)
RIGHT
RIGHT
Analog
DIGITAL
LNBC RECEIVER
Audio
(1+1)
LEFT (Stereo)
UPLINKING SET UP RECEIVE/ HUB
STATION

6. TYPICAL MOBILE DSNG SYSTEM
LOOKS LIKE

7. Lay out of Mobile DSNG System

8. TYPICAL FLYAWAY DSNG SYSTEM LOOKS LIKE

10. Lay out of Fly Away DSNG System

11. COMPONENTS OF DSNG SYSTEM
• MOBILE DSNG OUTDOOR UNIT : EASILY DEPLOYABLE
1.2M ANTENNA UNIT MOUNTED ON TOP OF THE VEHICLE ALONG WITH
ACCESSORIES LIKE LNBC

12. Cont…
• INDOOR UNITS :
– BASEBAND UNITS LIKE ENCODER,MODULATOR.
– UPCOVERTERS,SSPA
– UPS, PETROL GENERATOR.

13. DESIGN CONSIDERATION
• Weight consideration.
• Link Budget calculation.

14. 1. LINK BUDGET CALCULATIONS
1. Antenna Gain :
G = Gain of Antenna
D = Diameter of Antenna
D = Wave length
= = Efficiency (usually 0.5 to 0.65)
The gain if the antenna under consideration
= 37 dBi.

15. LINK BUDGET CALCULATIONS
Cont….
2. Transmit Station EIRP: 10 Log (Pt x Gt)
Pt = Out put Power of SSPA/HPA in Watts.
(Say : 10Watts = 10 dBw)
Gt = Gain of Antenna ( 37 dBi)
EIRP = 10 dBw + 37 dB = 47 dBw

16. LINK BUDGET CALCULATIONS
Cont….
3. Flux density at Satellite Antenna Input :
= EIRP -162.2 (47 - 162.2 = 115.2 dBw/M2)
3. Path Loss :
Lp = Path Loss
d = Distance between uplink site &
Satellite
(approx 36,000,000 meters)
( = Wave length
In our case it is about 200 dB at 6 GHz

17. LINK BUDGET CALCULATIONS
Cont….
• C/No (uplink) = EIRP + G/T(sat) + Lp – k
= 47 + (-2) + (-200) – (- 228.6)
= 73.6 dB-Hz
• EIRP(downlink) = Sat. flux density(operating)
+ (Sat. EIRP Saturated – O/P Back-off)
+ (S.F.D. - I/P Back-off)
= -115.2 + (38 – 4) - (- 85 – 6.5)
= 10.3 dBw

18. LINK BUDGET CALCULATIONS
Cont….
1. Down Link Path Loss :
(In our case it is about 196 dB at 4 GHz)
• Receive G/T (6 m antenna) = 25.5 dB/°K
• C/No (downlink) = EIRP + G/T(CES) + Lp – k
= 10.3 + 25.5 – 196 + 228.6
= 68.4 dB-Hz
7. Eb/No. = C/No – 10 Log (Data Rate) [256kbps]
= 68.4 – 54.1 = 14.3 dB.

19. DA-20 OFFSET ANTENNA
BLOCK DAIGRAM DSNG MOTORIZEDFLYAWAY
ANTENNA PSU WITH
DAUL FEED 1.2 mts.
z
GIGASAT
EMERGENCY STOP GH
ANTENNA GIGASAT .65
-6
CONTROLER 8
5. LNA
AES/EBU GIGASAT STC 100
ANTENNA PSU
3.4 - 4.2 GHz ( - 80 dBm)
LEFT
ISO UP CONVERTOR C-BAND I/P AC 100-240V
L
MPEG I GIGASAT SOLID STATE POWER AMP.
ENCODER MODEM O/P AC 100-240V
PAD L-II - 15 dBm - 22 dBm CODAN
DAC 700 DMD 20 UCU 60 120 W 15V DC O/P
COMSTREAM RADYNE C BAND C - BAND 40 dBm
70 ± 18 MHz
R
6.0 GHz
L
WAVE GUIDE
CO-AXIAL CABLE
CO-AXIAL CABLE
WAVE GUIDE
PAD
ENCODER MODEM
UCU 60 120 W
DMD 20
RIGHT
DAC 700 DATA C BAND C - BAND
COMSTREAM CABLE RADYNE
R
MODEM
CO-AXIAL CABLE
WAVE GUIDE
CO-AXIAL CABLE
70 MHz
ALARM CABLE
SWITCH.
CO-AXIAL CABLE
CO-AXIAL CABLE
ALARM CABLE
ALARM CABLE
DUMMY
ALARM CABLE
ALARM CABLE
SPLITER
ALARM CABLE
AES/EBU SPLITER LOAD
UP
CONVERTOR RF SWITCH
SWITCH.
CO-AXIAL CABLE WAVE GUIDE
MODEM, UPCONVERTOR & SSPA RF SWITCH
CHANGE OVER SWITCH CHANGE OVER
SIGNAL
7812 7812
+12 V CABLE +12 V CABLE
MAINTENANCE &
COMMAND SETUP
LEFT CO-AXIAL CABLE CO-AXIAL
ABR 202A CABLE DAUL LNBC UNIT LAB TOP
SPLITER 1:4
CO-AXIAL CABLE
ANALOG AUDIO
LNBC
RIGHT - 40 dBm USB CABLE 2 USB CABLE
SWITCH LNBC
1
LEFT
ABR #2
SPLITER SPLITER
ABR#1
ABR 202A MOXA MOXA
CO-AXIAL CABLE LNBC
RIGHT CO-AXIAL
SPECTRUM CO-AXIAL CABLE CABLE
ANALYZER
COM 13
COM 12
COM 11
COM 10
COM 9
COM 8
COM 7
COM 6
LNBC REDUNDANCY
CONTRLLER DC MONITOR
PCB
LNA PSU

20. SUBSYTEMS OF DSNG
DSNG ANTENNA: Gigasat make
Features:
– Carbon Fiber make antenna . Weight is less than 90Kg
– High efficiency offset feed design providing maximum
gain – 37dBi
– Antenna can be stowed.
– STC-100 antenna controller enables antenna to acquire
and track satellites.
– Manual and motorized operation of all the three antenna
motors.

21. SUBSYTEMS OF DSNG
Cont…
Antenna Controller:
• STC 100 is a comprehensive controller available in 1RU providing
all facilities including
– Stow/Deploy
– Jog Control
– Auto positioning
– GPS Receiver
– Flux Gate Compass
– Store/Recall Memory.
• Communication between STC-100 and Antenna is through an
RS485 cross-site connection to the Local Antenna Control unit
situated in the antenna cowl.

22. Antenna Controller Interface diagram:

23. SUBSYTEMS OF DSNG
Cont…
120W SSPA. CODAN Make
Features:
– 120Watts SSPA
– 5.85Mhz to 6.425Mhz frequency range
– Third order intermodulation Products is better than
-25 dbc for 3dB Back-off.
– 1+1 hot standby configuration.
– 65dB gain
– Innovative RF Power Combining technology, the latest
GaAs FET devices & Surface – mounted technology are
used in this SSPA

24. SUBSYTEMS OF DSNG
Cont…
C-Band Upconverter : Gigasat Make
Features:
• IF to C-Band Upconverter
• Output power : +9dBm (max.)
• Gain adjustments : >40dB in 0.5dBsteps
• Two stage Upconversion i) from 70MHZ to L-Band
ii) from L-Band to C-Band
• RF flatness across the band ±1dB max

25. SUBSYTEMS OF DSNG
Cont…
IF Modulator: Radyne Comstream Make DMD20L
• Modem provides the operation of different parameters such
as variable data rates, FEC code rate, modulation type, IF
frequencies, interface type can be readily set & changed at
the front panel.
• This allow the remote control from computer using RS232.
• This modem contains a selectable RS232 or RS485
asynchronous Com Port for Earth Station – to – Earth Station
communications. The baud rate & protocol can be selected
from the front panel.

26. SUBSYTEMS OF DSNG
Cont…
IF Modulator: Radyne Comstream Make DMD20L
Features:
– IF Frequency Range 52MHZ to 88MHZ
– Transmit Power: -5dBm to -25dBm
– Supports Data Rates: 64kbps to 256 kbps
– Supports QPSK and BPSK
– FEC – Viterbi ½
– Supports monitoring and Controlling

27. SUBSYTEMS OF DSNG
Cont…
Encoder: Radyne Comstream DAC700
Features:
• Digital Audio Codec
• ISO MPEG I Layer-II Compression
• Supports Data Rates: 64kbps to 256 kbps
• Accepts Analog and Digital AES/EBU input
• Supports monitoring and Controlling

28. SUBSYTEMS OF DSNG
Cont…
Digital Satellite Receiver
Radyne Comstream ABR202A

29. SUBSYTEMS OF DSNG
Cont…
REDUNDANCY CONTROLLER UNIT, RFS - 60
• RFS – 60, Make GIGASAT is used to control 3 switches: One switch
for encoders / modulators, one switch for the up converters and
one wave guide switch for the amplifier.
• The front of the controller has LEDs that display the status of each
pair of equipment.
• In normal use the switches are set in automatic position.
• For any failure the unit will automatically switch away from the
faulty peace of equipment.
• If both chains of equipment are normal either chain can be
selected.

30. SUBSYTEMS OF DSNG
Cont…
• 5KVA Petrol generator

31. SUBSYTEMS OF DSNG
Cont…
Hydraulic Jack System

32. THANK YOU