CONTROL AND INTERFACE DETAILS
2. MONITORING AND CONTROL INTERFACE
The interface for remote monitoring and control is through ETHERNET, which allows full control from a remote M&C computer located in the ground station. The complete status information of the servo system: Antenna position, command angles, mode status, receiver AGC, lock status, AZ/EL errors, drive system status and alarms, limits etc is transmitted to the M&C computer.
Antenna control servo system (Through RAC) will be able to send/receive through ground station LAN all relevant data for real time support or offline support functions, such as
a. Full remote control/operation of ACSS b. Schedule listing for passes to be supported.
ISTRAC/ ISRO (April 2016)
Page ( 37 )
c. Time tagged angle data transmission d. System status data transmission
e. Communication under TCP/IP protocol 2.1 M&C DETAILS FOR ACSS
1. For remote monitoring and control of Antenna Control Servo System, the interface is through decodable commands transacted between the systems using the standard TCP protocol on LAN.
2. Under TCP protocol, Servo system will be the Server accepting connection from the remote client system anytime on defined TCP ports.
3. All parameters information (including test, calibrations, system setups etc.) available locally should be present on the remote interface as well.
4. There should be a single monitoring command to get all the parameters, the format should be byte oriented. The format may be as follows
Command: ALL? Response:
Header Data Values Trailer
Example
Byte 0: A
Byte 1: L
Byte 2: L
Byte 3: 0 // Servo system Mode
Byte 4: 0 // Alarms/warnings
.
. .
Byte n: \r
Byte n+1: \n
Note that this only a sample and need not follow the same byte pattern
5. Group-wise monitoring commands and individual parameter monitoring commands can also be available.
Example: To get the current antenna azimuth ‘ANT.AZ?’, should respond with ‘ANT.AZ=2.5’;
6. All parameters controlled locally should be available for remote commanding as well. These command formats will be text oriented. Example, to change the antenna mode the command can be given as ANT.MODE = AUTO;
7. It should be possible to chain both monitoring and control commands. Chained commands and responses should be delimited by any character (; , : etc.). The system should be able to accept the maximum number of commands while chaining the commands. If monitoring commands are sent the response should also be sent in the same order. Example
Command: ANT.MODE?;ANT.AZ?;ANT.EL?;ANT.AGC? etc Response:
ANT.MODE=REMOTE; ANT.AZ=60.0;ANT.EL=30;ANT.AGC=5.25; etc
8. The response time for any monitoring commands should be less than 10 msec. This means, once a request for monitoring data has been sent, the response for that should come within 10 msec. Similarly, when a control
ISTRAC/ ISRO (April 2016)
Page ( 38 )
command is given, the control operation should get executed within 10 msec, so that it will be observed in the next monitoring data.
9. It is required to have multiple port connection for M&C. This means, an socket (port) can be identified to accept both monitoring request and control commands from a single client whereas, there can be another port to which multiple clients can get connected and receive only monitoring data in the desired requested format.
10. M&C status (in terms of connection) should be available in the local interface.
3. SYSTEM CONTROL OPTIONS
The enclosed Table summarizes the control options envisaged through the ACSS. Sl. no CONTROL OPTION REMARKS 1. Control Option (1) Operator Controlled (LOCAL MODE via RAC)
• Operator controls all functions of Servo system through various operating modes.
• Data output to Station Computer.
• Receipt of orbital elements through Station computer/M&C remote computer in off-line mode. 2. Control option (2) Unattended and schedule based (LOCAL AUTOMATIC via RAC) (stand alone)
• Receipt of orbital elements through Station Computer/M&C remote computer in off-line mode. • Receipt of schedules (containing Satellite, Time,
AOS, LOS, Support start time, Support end time, scheduled/not scheduled etc.) through Station Computer/M&C remote computer in off-line mode. • Unattended operator free total control of antenna
through schedule based events. • Data output to Station Computer. • No real time dialog with M & C. 3. Control Option (3)
Through M&C - Operator
(Remote Operation)
• Receipt of orbital elements through Station Computer/M&C remote computer in off-line mode. • Real-time control of all functions of servo system
through various operating modes by M&C operator. • Data output to Station Computer and M&C
computer.
• Real-time dialog with M&C computer for receipt of commands and transmission of status.
4. Control option (4) Unattended and schedule based from M & C.
(Remote Operation)
• Similar to Control Option (2) including Real Time dialogue with M&C computer for receipt of commands and transmission of status and angle data.
ISTRAC/ ISRO (April 2016)
Page ( 39 )
Interface Description
1.1 EXTERNAL INTERFACES To ACU (Antenna Control Unit) S
No SYSTEM INTERFACE DETAILS REMARKS
1. Tracking Rx-1
(X-Band Rx) 1. AGC 2. Azimuth Error : (0-10) V DC, Analog : + 10 V Analog.
3. Elevation Error : + 10 V Analog.
4. Lock Status : 0/5 V, TTL.
Connector Type : 15 pin D-type female
Input to ACU 2. Tracking Rx-2
(S-Band Rx) 1. AGC 2. Azimuth Error : (0-10) V DC, Analog : + 10 V Analog.
3. Elevation Error : + 10 V Analog.
4. Lock Status : 0/5 V, TTL.
Connector Type : 15 pin D-type female
Input to ACU 3. Beacon
Receiver 1. AGC : (0-10)V DC, Analog. Input to ACU
4. Timing system 1. Mod. Code (IRIG-B) Input to ACU
1.2 EXTERNAL INTERFACES To RAC (Remote Antenna Console)
SNo. SYSTEM INTERFACE DETAILS REMARKS
1. LAN-1 Main Link-CDM
I/F Type : ETHERNET
Protocol : UDP/IP
Data Rate : 10 Packets/Sec
Packet Size : 19 bytes Format : Byte Oriented Status Data
I/F Type : ETHERNET
Protocol : UDP/IP
Data Rate : 1-10Packets/Sec
(Programmable)
Packet Size : 300 bytes Format : Byte Oriented
From CONTROL CENTER (SHAR) To CONTROL CENTER (SHAR) via Status PC of G/S
2. LAN-2 Redundant Link-CDM
I/F Type : ETHERNET
Protocol : UDP/IP
Data Rate : 10 Packets/Sec
Packet Size : 19 bytes Format : Byte Oriented Status Data
I/F Type : ETHERNET
Protocol : UDP/IP
Data Rate : 1-10Packets/Sec
(Programmable)
Packet Size : 300 bytes Format : Byte Oriented
From CONTROL CENTER (SHAR) To CONTROL CENTER (SHAR) via Status PC of G/S
1. Station Computer (STC)
ISTRAC/ ISRO (April 2016)
Page ( 40 )
Protocol : TCP/IP
Data Rate : 1/10 Packets/Sec
(Selectable)
Packet Size : 90 bytes Format : Byte Oriented 2. Second Servo System (Master/Slave).
I/F Type : ETHERNET
Protocol : TCP/IP
Data Rate : 10 Packets/Sec
Packet Size : 19 bytes Format : Byte Oriented
Time Tagged Angle Data (Both Receive
and Transmit) to
second servo system 3. M & C (Monitor & Control System)
(A) Status Data
I/F Type : ETHERNET
Protocol : TCP/IP
Data Rate : 10 Packets/Sec
Packet Size : 300 bytes Format : Byte Oriented No. of Connections : 5
(port no. e.g. 5000)
(B) Control Data
I/F Type : ETHERNET
Protocol : TCP/IP
Data Rate : Asynchronous
Packet Size : Variable Format : Tag Oriented No. of Connections : 1
(port no. e.g. 5001)
From RAC to M & C
(RAC is Server) Unidirectional communication.
No response from RAC to MCS for control command from MCS . However RAC sends complete status packet (on port no. 5001)when request comes for monitoring data.(Bi-directional communication)
2. 4. Time Server
I/F Type : ETHERNET
Protocol : TCP/IP
Time information from GPS Rx.
ISTRAC/ ISRO (April 2016)
Page ( 41 )