Pccir, Pdzvei – Wavecom W61PC V7.5.0 User Manual
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WAVECOM Decoder W61PC/LAN Manual V7.5
Transmission Modes
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two CRC bytes. This input bit stream is then bit-interleaved and convolutional encoded. After that, the
symbol mapping for the different channels is done, and the resulting signals are applied to the DxPSK
modulators.
To extract the data from a PACTOR-III signal, the signal is demodulated with the appropriate number of
DxPSK-demodulators, according to the speed level. The center frequency must be adjusted to the center
between the lowest and highest tone in use. AFC (automatic frequency control) can be switched on or off.
After demodulation and bit synchronization, the symbols of the channels are combined to one bit stream,
which is de-interleaved and passed through a Viterbi-decoder. The CRC is used to check whether trans-
mission errors occurred. After successful synchronization, it may take several tens of seconds before any
text is output in the GUI.
In PACTOR-III, the data may be transmitted as ASCII without compression or can be compressed with
HUFFMAN or PSEUDO-MARKOV compression (PMC). In addition, run length encoding (RLE) is included.
PCCIR
The entire call number is transmitted by consecutive tones in decade sequence. When two identical digits
are to be transmitted consecutively, then an eleventh frequency is used as a repetition identifier.
Parameter
Value
Frequency range
VHF/UHF
Operation modes
Analogue Selcal
Modulation
FM, SUB tone
Receiver settings
FM, BW = 12 kHz
Input format(s)
AF, IF
If more than two identical digits are to be transmitted, the repetition tone is appended to the digit tone
(e.g. 22222 is transmitted as f2 fw f2 fw f2, where f2 is the tone for "2" and fw is the repetition tone).
In most systems the accuracy of the single frequencies has to be within +1/-1% of the nominal value.
Decoding the selective calls is started by clicking on a system. If transmission and system selection con-
form, the call sign is displayed on the monitor. In the Options menu a Time stamp function can be ena-
bled to add date and time to each call.
Tone Allocation
Digit
Hz
Digit
Hz
0
1981
8
1747
1
1124
9
1860
2
1197
A
1050
3
1275
B
930
4
1358
C
2400
5
1446
D
991
6
1540
E
2110
7
1640
TONE DURATION: 100 ms
PDZVEI
The entire call number is transmitted by consecutive tones in decade sequence. When two identical digits
are to be transmitted consecutively, then an eleventh frequency is used as a repetition identifier.
Parameter
Value