SAT-C
VASUDEVAN PONDICHERRY PH: 91 96299 80476
Two EGC types of
available
SafetyNET, which
is used to broadcast Maritime Safety Information (MSI) to ships.
FleetNET, which is
used
typically
by companies to
send commercial information to ships belonging to their fleet
What service is offered by SAT-C?
Store
and forward data communication
Explain ‘store and forward data
communication’.
sending text messages or data to SES
and from an SES, using “store-and- forward” messaging.
It is stored in SES
After a short delay the message/data will be delivered to the recipient’s terminal, where it may be printed, viewed or stored.
What is the delay made in this
communication?
2
to 5 minutes
What is the power output (EIRP)?
14
dbW
What is the speed of transmission?
600
bauds
Type of aerial? Size of the aerial?
Small
Omni directional antenna, 10 TO 13 cm in dia
What is the transmitting (uplink)
frequency?
1.6
GHz ( 1626.5 – 1660.5 MHz)
What is the receiving (downlink)
frequency?
1.5
GHz (1525.0 – 1559.0 KHz)
Why SAT-C is preferred to use on board
ship?
It
can be fitted on any type of vessel
Low
cost, EGC and LRIT
What is BDU?
Below
deck unit
It
is the transceiver of SAT C
What are the methods to inform RCC
about Distress condition?
Undesignated
distress alert
Designated
distress alert
Detailed
distress message
How do you send undesignated distress
alert?
How do you send designated distress
alert?
What are the differences between
undesignated and designated distress alert?
Undesignated
distress alert,
Ship’s
SAT-C ID, position, time and nature of distress –undesignated
Are
sent ( to RCC)
Designated
distress alert –
Ship’s
SAT-C ID, position, time and NATURE OF DISTRESS (select) are sent (to RCC)
How do you send distress message?
By
selecting Distress priority
Who receives the
undesignated/designated distress alert and Distress message?
RCC
How do you send URGENCY or SAFETY
messages in SAT-C?
By
using two digit special access code
What is EGC?
Enhanced
Group Calling
What is safetyNET?
Safety
NET For receiving MSI
What is fleetNET?
Fleet
NET for commercial messages sent from companies to their ships
You have sent distress alert to RC C
and no response is received. What action
Will you take?
Repeat
after 5 minutes
What is log-in?
Connecting
to NCS
Why do we log-in?
To
get a common signaling channel
By
that we can communicate in maritime satellite communication network.
What is the purpose of log in?
By
log in to NCS, we are getting a common signaling channel.
Our
SAT ID is registered in the NCS DATABASE.
If
anyone sends message or calls, we can be connected
(
In SAT-C we do LOG IN manually, and in SAT-B and FLEET 77,
It
is automatically LOG IN)
How do you receive distress relay
messages in SAT-C?
EGC
–SAR message
What are the services can be connected (delivered) to shore?
Email,
telex, fax
What is data reporting?
Position
reporting at pre fixed intervals – send to shore
What is polling?
From
shore, by giving a polling command to ship’s SAT-C ID
Position
report will be taken
What is DNID?
For data reporting and polling through SAT C, ship station should have
DNID
Data Network Identification Code
For using data reporting and polling service through SAT C, company
should apply to Inmarsat with DNID
DNID
– Data Network Identification Number is used for data reporting-LRIT polling
What is Link test?
It
is also known as PV TEST.
PV
TEST means performance verification test.
It
is checking whether the SAT-C equipment meets the INMARSAT specifications.
What is LOOP TEST?
It
is a guide how to send a message through SAT-C network and back to yourself.
It
is checking the SAT-C network.
Method:
Type the ocean region (where you are in) and your ship’s SAT-C ID and transmit a
test message
A
copy of message is saved in received log.
What is common in undesignated
distress alert, designated distress alert and distress message?
These
3 are sent to RCC.
We
receive immediate acknowledgement from RCC
Is it store and forward in distress
message transmission?
No.
it is directly sent to RCC.
Other
messages are store and forward except distress message
VASUDEVAN PONDICHERRY PH: 91 96299 80476
Speed of data in SAT-C?
Telex
- 5 bit code
ITA-2
International Telegraph Alphabet
Telex
over PSTN –to – a FAX terminal – 7 bit code
DATA
over PSDN landlines – 8 bit code
PSTN
– Public Switched Telephone/Telex Network
PSDN
– Public Switched Data Network
What is X.25?
It
is the communication protocol, used on National/International PSDN Networks-
To
exchange Digital Data between
terminals connected to the network.
What is X.400?
It
is the communication protocol, used on National/International PSDN Networks-
To
exchange messages and electronic files
between terminals connected to the network.
5
bits- shore telex 7 bits – message over PSTN
8 bits – message over PSDN
SAT-C
services:
Distress alerting, distress message transmission through distress priority, 2
digit special access code for urgency, safety, position reporting and other
services, EGC and position reporting and polling via LRIT
SAT – C CONNECTIONS:
E
MAIL
TELEX
or FAX (ONE WAY ONLY)
Connected
to PSTN and PSDN using telephone modem number
Another
SAT-C terminal/MINI-C terminal
Special
access code
KEYWORD: GMDSS VASU
