2. This is to certify that Mr. Srijan Kumar has completed
the Summer training on “Satellite Communication in
ONGC” during 1st
July 2011 to 30th
July 2011 at ONGC
Vasundra Bhavan,Bandra(East) under the guidance of
Mr. Vikas Shinde, Chief Engineer(E &T).
Vikas Shinde
C.E.(E&T)
C.E(E&T)
3. Mumbai high asset is biggest oil & gas field in
western offshore.The field is located about 165
kilometers away in Arabian sea at a water depth in
70 to 80 meters.
The field was discovered in 1974 by the legendry
rig sagar samart.The field producing about
2,60,000 barrels of oil per day.
The backbone of the offshore facility comprises of
5 process complexes
MNW,NQP,BHS,SHP,ICP,24 process platform
and 107 unmanned well platforms 665 oil wel
4. In the ONGC platter there are 665 oil wells.34 free
gas wells and 183 water injection wells besides a
pipeline network of approx. 4000kms.
ONGC has its own telecommunication network
which connects its HQ at Dehradun to all regional
offices located all over india,Offshore Rigs and
Process Platforms.This network is known as
ICNET.
There are various methods in wich we can gain in
formation from one part of the place to other
through satellite communication it includes voice
and data communication.
5. Oil and natural gas coorporation has approached
the department of telecom for allocation on
spectrum to setup a captive communication
network for its Western Offshore site.
The oil PSU has sought permission to build a
captive communication network based on
Broadband Wireless Access System for the
Western Offshore location in the 3.3 GHz frequency
band.
Earlier, such request of ONGC has been
considered for BWA system in the 3.3 Ghz band for
on shore locations in Gujarat.
8. A private branch exchange is a telephone exchange
that serves a particular office or a business.
This is the opposite of one that a common carrier or
telephone company operates for many businesses or
for a general public.
The EPABX in the above used system is only for the
transmission and the reception of the voice signals via
satellite. The EPABX makes connection among the
internal telephones of a private organization and also
connect them to the general public using ISDN, MTNL
lines.
9. ISDN is a set of communication standards for
simultaneous digital transmission of voice, video data
and other network services over the traditional
circuits.
ISDN are of two rates :-
1) Basic Rate Reference
2) Primary Rate Reference
Integrated Services Digital Network
(ISDN)
10. Integrated Services Digital Network
(BRI)
The entry level interface to ISDN is the basic rate
interface. A 128 Kbit/s delivered over a pair of
standard telephone copper wire.
The 144 Kbit/s payload rate is broken into two 64
Kbit/s and one 16 Kbit/s signaling channel. This is
sometimes referred to as 2B+D.Here B refers to
64 Kbit/s and D refers to 16 Kbit/s.
11. B refers to the ISDN channel in which the B
channel(bearer) is a telecommunications term
which the primary data or voice communication is
carried.It has a bit rate of 64 kbit/s in full duplex.
D channel(data) is a telecommunication terms
which refers to the ISDN channel in which the
control of signalling information is carried.
The bit rate of the D channel of a basic rate
interface in 16 kbit/s and in primary rate interface
it is 64 kbit/s.
12. ASDL is a form of DSL,a data communication
technology that enables faster data transmission
over copper telephone lines than a voiceband
modem can provide.
ASDL is generally offered at downstream data rated
from 512 Kbp.As to about 6 Mbps.ADSL was
specifically designed to exploit the one-way nature of
most multimedia communication in which large
amounts of interactive control information is returned.
13. A MUX or a multiplexer combines the many voice
& Data signals into a single path and gives the
output to the modem. It is used only for both the
voice & data signals.
The MUX used is Alcatel Make & Model is
Mainstreet 3600/3600+ .There are various cards
having different functionalities and installed in the
MUX.
15. A modem is a device that modulates an analog
carrier signal to encode digital information and
also demodulates such a carrier signal is to
decode the transmitted information.
It is a microprocessor controlled BPSK,QPSK or
OQPSK for use as part of transmitting or receiving
equipment in a communication system. The
modem is designed for service in an SCPC
(Single Channel Per Carrier) system where two
modems are set for operation.
16. The radio frequency up-converter is a device
that takes an input of intermediate frequency
of a specific frequency range and outputs it on
a higher frequency.
The up-converters are designed for use in the
communication system on satellite uplink data
systems for the transmission of SCPC,DAMA
and TDMA communication signals.
The RF output frequency range for the up-
converters used in the above is as follows.
UT-4505 5845-6425 MHz
17. A radio frequency down-converter is a device that
takes an input of higher frequency energy of a specific
frequency range and outputs it on a intermediate
frequency.
The down-converters are designed for use in the
communication system on satellite uplink data
systems for the transmission of SCPC,DAMA and
TDMA communication signals.
The RF output frequency range for the up-converters
used in the above is as follows.
DT-4503 5845-6425 MHz
18. A router is a networking device whose software
and hardware are usually tailored to the tasks of
routing and forwarding information.
The router in the communication system above is
used for the data to be transmitted from one end
to the other.
Router consists of two major aspects of internet
which is useful for the users they are lan and wan.
19.
20. LAN is Local Area Network and WAN is wide area
network.LAN and WAN were the original
categories of area networks.while the others have
gradually emerged over many years of evolution.
A LAN connects to network devices over a
relatively short distance. In TCP/IP networking, a
LAN is often but not always implemented as a
single IP subnet.
A WAN is a dispered collection of LANs.A network
device called a router connects LANs to a WAN.
21.
22. SSPA in a HPAC series offer premium
performance and reliability for satellite uplink
calculations. These C band high power
amplifiers provides linearity and gain stability.
Features of SSPA :-
1) Frequency range: 5.85 to 6.425 GHZ
2) Output Power @ 1db Gain compression is 50.6
dbm.
3) Temperature compensation
4) 20 DB gain adjustment
5)1:1 Redundant system
23. The low noise amplifier is a special type of electronic
amplifier or amplifier used in comm. Systems to
amplify very weak signals captured by the antenna.
LNA is very close to the antenna. It is a key
component, which is placed at the front-end of the
radio receiver circuit.
So it is necessary for an LNA to boost the desired
signal power while adding as little noise and distortion
as possible so that the retrieval of this signal is
possible in the later stages in the system.
24. The 6.3 meter earth station antenna meets
international specifications & is installed at ONGC.
The reflector consists of 40 dual shaped panels
placed in 3 rows over 16 trusses emanating from the
central hub.
The antenna features shaped cassegrain paraboloid
configuration with a conical corrugated horn,
sub-reflector. The centre hub is spacious to
accommodate receive electronic equipments.
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MOTOR
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LNAL-
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OUTPUT
ANTEN
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COMSAT SYSTEMS PVT LTD
