Details of Signal Flow in the C & M system


So for, You have been exposed to the functions of C & M system,various data rates used by the system and the type of modulation used etc.But how all these things are achieved ? This system block diagram will give you a clear idea of the inner workings of the C & M system and the signal flow thro' the various sub systems.

Already you have seen the operation and command flow of the ONLINE system.But this block diagram will give you an idea about the data flow and how the various data rates are used.User commands for various antennas are processed by UNIX WS and sent to the COMH thro' the PC router.The PC router acts as a buffer and accepts the TCP/IP data @ 10 Mbits/sec(Link A),strips the TCP/IP headers and sent it as asynchronous data with the headers to COMH @ 38.4 Kbits/sec.This RS232-C link(Link B) is converted to RS 422 signals (differential TTL signals) and viceversa.

Details of various communication links used in the C & M system of GMRT


(A) ETHERNET LINK    ---------  UNIX WS    <=====> PC ROUTER ----- 10 Mbits/sec

(B)  ASYNCHRONOUS --------- PC ROUTER <=====>    COMH       ----- 38.4 Kbits/sec
RS232 -C LINK - 10 BITS

(C) SDLC/HDLC LINK  ---------    COMH      <=====>  ANTCOM     ----- 125 Kbits/sec

(D) ASYNCHRONOUS ---------   ANTCOM  <=====>     MCM         -----   9.6 Kbits/sec
RS 485 LINK - 11 BITS

(E) ASYNCHRONOUS ---------   ANTCOM  <=====>   SERVO        -----   9.6 Kbits/sec
RS 422 LINK - 10 BITS

(F) FSK MODEM LINK --------    COMH      <=====>  ANTCOM      -----  250 Kbits/sec

(G) VOICE COMM        ---------      CEB        <=====>  ANTCOM       -----  62.5 Kbits/sec