Wavecom W61PC V7.5.0 - Manual (Page 294)

284  Modem and FAX modes WAVECOM Decoder W61PC/LAN Manual V7.5
ITU-T
Rec. User Data Rate [bps] User Input
Transmission
Format
Full or
Half-
duplex
2 or 4
Wire Modulation
V.27bis 4800/2400 Sync FDX 4W D8PSK
V.27ter 4800/2400 Fax HDX 2W D8PSK
V.29 9600 Fax FDX 4W 16QAM
V.32 9600/7600/4800 Sync/Async FDX 2W Trellis coded
32/16/4QAM
V.32bis 14400/12000/9600/
7200
Sync/Async FDX 2W Trellis coded
128/64/32/
16QAM
V.34 Up to 33600 Fax/Sync/Async FDX 2W Trellis coded QAM
V.90 Down: 56000
Up: 33600
Async FDX 2W Down: PCM, digital
Up: V.32 analogue
V.92 Down: 56000
Up: 33600
Async FDX 2W Down: PCM, digital
Up: V.32, ana-
logue.
“Internet call wait-
ing”
Decoding
The fax and modem decoding features depends on three software modules which analyze one or two in-
coming bit streams (calling and answering modems) in G.711 format (8 kHz sampling rate, A- or mu-law)
or a 16 bit linear format.
The first module analyzes the initial handshakes to route the bit stream(s) to the appropriate demodula-
tion modules – fax or full-duplex data - of the next stage.
The next module demodulates the signal, and echo cancellation is applied if in use.
The last module processes fax ECM (Error Correction Mode) as well as performing data link layer analysis
on data signals. The various fax and data modes are then decoded and output in a number of formats.