General Information
POL-ARQ is a synchronous duplex FARQ system. This system was used by the Ministry of Foreign Affairs of Poland.
Usage:
§ Data communication over HF.
Mode Details
|
Item |
Value |
Standard |
Modulation |
FSK |
|
Number of tones |
2 |
|
Shift (Hz) |
270 |
|
Symbol rate (Bd) |
100 |
|
Alphabet |
CCIR-476 |
Demodulator Settings |
Demodulator |
FSK 2 matched |
|
Symbol rate (Bd) |
100 |
|
SR tolerance (Bd) |
5 |
|
Shift (Hz) |
270 |
|
Shift tolerance (Hz) |
30 |
|
Modem type |
Synchronous |
Features |
Demodulation |
yes |
|
Recognition |
yes |
|
Decoding |
yes |
|
Automatic Polarity Adjustment |
no |
|
Combination with other modems (modem list) |
yes |
Tuning |
The tuning frequency is the center of the signal |
Table 174: POL-ARQ
Figure 60: POL-ARQ Spectrogram