Wavecom W-SPECTRA (Automatic Monitoring System) V1.1.0 - Manual (Page 171)

WAVECOM Monitoring System W-SPECTRA, W-SPEED Manual V1.1.0 Transmission Modes

161
Hexadecimal
value PID binary value Layer 3 Protocol
** xx10xxxx AX.25 layer 3 implemented
0x10 00010000 ISO 8208/CCITT X.25 PLP
0x06 00000110 Compressed TCP/IP packet. Van Jacobson (RFC 1144)
0x07 00000111 Uncompressed TCP/IP packet. Van Jacobson (RFC 1144)
0x08 00001000 Segmentation fragment
0xc3 11000011 TEXNET datagram protocol
0xc4 11000100 Link Quality Protocol
0xca 11001010 Appletalk
0xcb 11001011 Appletalk ARP
0xcc 11001100 ARPA Internet Protocol
0xcd 11001101 ARPA Address resolution
0xce 11001110 FlexNet
0xcf 11001111 NET/ROM
0xf0 11110000 No layer 3 protocol implemented
0xff 11111111 Escape character. Next octet contains more Level 3 protocol information
0x08 00001000 Escape character. Next octet contains more Level 3 protocol information.
RUM-FEC
Parameter Value
Frequency range HF
Operation modes Broadcast/Simplex FEC
Modulation FSK
Symbol rate 164.5 and 218.3 Bd, variable 30-650 Bd
Receiver settings DATA, CW, LSB or USB
Input format(s) AF, IF
Additional Info 16 Bit redundancy
RUM-FEC operates at symbol rates of 164.5 and 218.3 Bd on the radio link.
The HNG-FEC and RUM-FEC modes are technically very similar. RUM-FEC alphabet has a codeword length
of 16 bits where each of the 32 used bit combinations corresponds to an ITA-2 character.
The RUM-FEC alphabet is designed to obtain a maximum Hamming distance for error detection and has
deep interleaving. The actual ITA-2 alphabet is not contained in the code table. As in HNG-FEC error cor-
rection is performed by table look-up of the bit pattern (character) closest resembling the character in er-
ror.
RUM-FEC has a bit interleaving of 128 bits, each new character starting at intervals of 16 bits. The soft-
ware synchronizes to traffic as well as idle bit patterns.
Error correction may be enabled or disabled using the ECC item in the Options menu.
In RUM-FEC mode the signal polarity (sideband) can be manually selected by toggling the Polarity item in
the Demodulator menu. If polarity changes during a transmission, synchronization will not be lost.