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a 3G Multicast Data Link w/ NAKs?
few days ago, 16 Feb, I copied a 3G-HF transmission on 10958.0 KHz/USB consisting of an initial FLSU PDU (BW5 burst) followed by 13 not-ACKed LDL PDUs (BW3 bursts) and ending with a single BW4 burst:...
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chasing HAARP
photo from Chris Allen twitter accountOn 19-22 February, scientists used the HAARP (High-frequency Active Auroral Research Program) research instrument to conduct multiple experiments, including the...
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a new S4285-like waveform (most likely a new Iraqi waveform)
The signal appears on-air as a PSK-8 modulation of a 1800Hz single tone, symbols rate is the quite usual 2400 Baud (Fig. 1). ACF is 120 msec, that makes 288 PSK-8 symbols per frame or a 864-bit length...
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a possible variant of the CIS-48 OFDM modem
This signal was copied on 9905.0 KHz/USB at 0922 UTC 22 February, although the poor quality of the recording (it mostlydepends on the signalweakness) some interestingcharacteristicscan be obtainedfrom...
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Logs
06550.0: R26573: US Army Helo 1336 USB MIL 188-141 2G-ALE hadshake RAPTOR followed by voice comms (11Feb17) (AAI)06629.7: ---: Unid 0841 USB STANAG-4285 modem, 600bps/L KG84 encryption (11Feb17)...
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single couples of Fast LSU PDUs: what is the scenario?
Often, and on several frequencies, I noted isolated couples of Fast LSU PDUs (BW5 waveform) which exhibit the following characteristics:1) since the strength of the signals, the bursts seem to be...
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3G-ALE, 2-Way Link Quality Analysis (“LQA Exchange”) example
this is surely a post of few or zero significance, just to add another over-the-air scenario of those depicted in the NATO STANAG-4538 document.The diagram in Fig. 1 shows the procedure by which a PU...
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3G-ALE, Synchronous 2-way FLSU failure – packet traffic example
Fig. 1 shows the required procedure for a failed Link Set Up. All 2-way FLSU calls require only a Request and Confirm PDU transmission. The third handshake is issued only if the caller PU does not...
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Logs
[MIL-STD 188-141]03831.0: ZEMD: Zollboot Emden, D 2150 USB MIL 188-141 2G-ALE calling ZLST, no reply (01Mar17) (AAI)06562.0: J64: Moroccan Military, MRC 2130 USB MIL 188-141 2G-ALE sounding (09Mar17)...
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3G MDL with BW3-32 (LDL) burst waveform
Yet another over-the-air example of 3G Multicast Data Link (MDL) protocol copied on 7700.0 KHz/USB at 2206 UTC, 14 Mar: this time the BW3 waveform from the LDL protocol, the one with a 32-byte payload...
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Nokia Adaptive MSG-Terminal, FSK 401Bd/301Bd 780Hz shift
This is an interesting copy of transmissions sourced by the Nokia Adaptive MSG-Terminal (Nokia Sanomalaite M/90) in "dual" 401 (401.5) and 301 Baud mode, both running with constant 780 Hz shift and...
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a STANAG-5066 HF MailServer at work
this is a good example of a STANAG-5066 based HF Mail Server (an MTA, Mail Tranfer Agent) at work: the HF Mail Server receives one email transmitted by a wireless client (over-the-air path) which is...
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Logs (a lot of)
05316.0: Z1V: Slovakian Air Force, SVK 0842 USB MIL 188-141 2G-ALE calling M1I (21Mar17) (AAI)05350.0: ---: Unid 0733 LSB TADIRAN AutoCall MFSK-4 (21Mar17) (AAI)05426.0: SM8: Polish Military, POL 0743...
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STANAG-4538, HDL+ and LDL protocols swapping in a bidirectional link
This is a very interesting 3G-HF on-air scenario where as many as 5 burst waveforms and 2 datalink protocols are used, moreover, thanks to the different strength of the signals, it's also possible to...
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async FSK-2 50/100 Bd 500 Hz, "5-38" code (prob. CIS source)
Some day ago, me and my friend KarapuZ were talking about some asynchronous 500 Hz shift FSK-2 signals and the way to get a meaningful decoding from the demodulator of SA. The first step is the removal...
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xDL PDUs, BW2 & BW3 waveforms, and Harris 'Citadel' encryption
I spent some time to understand where and when the 'Citadel' encryption is applied to a message in the STANAG-4538 xDL implementation by Harris, eg in the RF-5800H transceiver, regardless of whether...
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recent Logs
05838.0: ABC7: Croatian Military, HRV 0734 USB USB MIL 188-141 2G-ALE followed by voice radio-check w/ ABF2 ABS5 ABH3 ABK4 (28Mar17) (AAI)06250.0: ---: Unid (prob. Turkish Mil, TUR) 0713 (cf) FSK...
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a possible EMCON retransmission mode for Multicast Data Link protocol ?
This is an MDL-N (Multicast Data Link with NACKs) transfer received on 10958.0 KHz/USB. The transfer begins with an FLSU Point-to-MultiPoint call (BW5) followed by four forward transmissions consisting...
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an LDL160 transfer with nine retransmissions
this is a copy of an 10 x LDL160 transfer, heard on 8327.0KHz/USB, with up to nine retransmissions of the same 'Citadel' encrypted data packet (Fig. 1). Since the LDL forwards are followed by ACKs...
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housing of data packets in a HDLn Tx Frame
This recording is nothing special but rather a good example in order to study and verify the way the data packets are housed in an HDLn Tx frame and the mechanisms used to fill the unused room when the...
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