POL-ARQ

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