Wavecom W61PC V7.5.0 User Manual
Page 206
196
Transmission Modes
WAVECOM Decoder W61PC/LAN Manual V7.5
Parameter
Value
Additional Info
ITA-5 with block coding
14.106 MHz, 21.112 MHz
Optional Mode
TONE
SL=1
SL=2
SL=3
SL=4
SL=5
SL=6
TF
0
Q
480
1
Q
Q
600
2
B
Q
Q
Q
720
3
B
B
Q
Q
Q
840
4
B
Q
Q
Q
960
5
B
B
B
Q
Q
Q
1080
6
B
Q
Q
Q
1200
7
B
B
Q
Q
Q
1320
8
B
Q
Q
Q
1440
9
B
Q
Q
Q
1560
10
B
B
Q
Q
Q
1680
11
B
Q
Q
Q
1800
12
B
B
B
Q
Q
Q
1920
13
B
Q
Q
Q
2040
14
B
B
Q
Q
Q
2160
15
B
Q
Q
Q
2280
16
Q
Q
2400
17
Q
2520
Tone numbers (TN) and respective frequencies (TF) in Hz as well as modulation types (B = DBPSK, Q =
DQPSK) for the 6 Speed Levels (SL).
As propagation conditions change, PACTOR-III is able to select the most suitable speed level. Under very
poor conditions PACTOR-III changes to speed level 1, whereas, under optimum conditions, speed level 6 is
used. As in the previous PACTOR standards, the frame durations are still 1.25 seconds (short cycle) and
3.75 seconds (long cycle for data mode). Again, a long path option is available to enable contacts up to
40.000 km. In such a case, the duration of the short and long cycle is extended to 1.4 and 4.2 seconds,
respectively.
Initial link establishment is achieved using the frequency shift-keying (FSK) protocol of PACTOR-I, corre-
sponding to the lowest protocol level. If both calling and called stations are capable of PACTOR-III, auto-
matic switching to this protocol is done.
For data transmission, which is robust against all kinds of disturbances, a decision must be made, whether
a short or a long frame-length should be used. Each frame consists of the user data, a status byte, and