Interesting and unknown (at least for me) FSK transmission in 800Bd/850Hz mode sent to me by my friend cryptomaster. These transmissions can be heard during the evening (UTC) on the frequencies 8014, 8180, 10008 and 12414 kHz.
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| Fig. 1 - FSK parameters |
The signal has an ACF of about 1280 ms which corresponds to a period of 1024 bits (Figure 2).
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| Fig. 2 - ACF value and comparative bitmap |
The bitstream obtained after demodulation has a complex and very interesting structure (Figure 3).
Fig. 3 - demodulated bitstream
The 850 Hz shift most likely belongs to NATO radio networks.
