Technical Manual

M7 GX Technical Manual 37 Raveon Technologies Corp.
not ne encrypted in the ATDEN 0 mode. GPS position transmissions will be
encrypted with AES128 if the KEYPHRASE is set to anything but 0.
ATDEN 2 AES128 data encryption
Data Encryption mode 2 is to force the M6 modem to encrypt all transmissions with
AES128 methodology. The packets may become a little longer than unencrypted
packets. AES128 requires the transmission of a minimum of 16 bytes of data, so
even if the modem is going to send 1 byte of data in its over-the-air payload, 15
more area added to the transmission, and upon reception, the added bytes are
discarded and the one payload data byte will come out the serial port.
As long as the KEYPHRASE in each radio modem communicating is set exactly
the same, then data in on one will be the same data out on another. In ATDEN 2
mode, all received data must have come from a modem that encrypts the data. If it
receives unencrypted data, the receiving modem will discard the received data and
not output anything from its serial port.
8. Using the M6G as GPS Transponder or Receiver
This section describes the operation of the M6G as a GPS transponder and GPS
position report receiver. An M6G can perform either or both functions. It can be a
GPS transponder by reporting is location and status. It can receive GPS position
reports over the air, and output them via its serial port for display or logging.
1. Connect a DC power source to the DC IN connection on the front of the
modem.
2. Connect a good quality antenna, cut to the operating frequency, to the RF
connector on the front of the modem. Use a good quality antenna, and place it
as high-above obstructions as possible.
3. Connect a computer terminal, or PC computer running HyperTerminal, to the
serial I/O connector. The serial I/O connector is 3.3V digital logic, so you may
need a digital-RS232 voltage converter. Raveon’s Tech Series enclosures
have these built, so you may plug the RV-M6G into the “S” interface of a Tech
Series to do the RS232 conversion. USB and RS485 are also available in the
Tech Series. The factory default serial ports settings are 4800 bps, 8 data bits,
1 stop, no parity. Note, the serial port may be 38400bps if the M6G is in GPS
modes 2 or 3.
4. Put the M6G into the command mode. (enter +++ per Section Error!
Reference source not found.)
5. Program the modem’s operating frequency to your desired operating frequency.
This is done with the ATFX xxx.xxxxx command. See the Section Error!
Reference source not found. for information describing the various
parameters that may be modified in the modem. In most applications, the
default settings from the factory will work fine.
Note: The MURS version of the M6G (M6G-VM), the unit is pre-set to the 5