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NILE/Link-22, likely QAM traffic waveforms
Two NILE/Link-22 close channels recorded this morning (26th October) on 14.656 KHz and 14.659 KHz using a remote AirSpy server located in Romania [1], traffic in the two channels flowed in alternating...
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Akula 250Bd/500 FSK version
A friend of mine, whom I'm grateful, sent me this interesting and quite rare example of the Akula 250Bd/500 FSK waveform. Transmission was recorded on 9202 KHz around 0800 UTC using a Japanese SDR: as...
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unid MFSK-17 125Bd
Unid (probably Russian) MFSK-17/125 125Bd burst transmission heard on 21292 kHz USB (15mt HAM band) USB at 0830 UTC. Fig. 1Fig. 2The same waveform was already noted six years ago(!) and reported in...
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a new family of wideband OFDM waveforms
A new family of wideband OFDM signals has recently appeared on-air, most likely tests of Russian origin, and which - at least according to the observations carried out so far - seems to be composed of...
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16Kbps/16KHz encrypted wideband FSK (WBFSK)
Unid 16Kbps/16000 wideband FSK (WBFSK) heard and sent me by my friend Martin on 31875 KHz, just a bit beyond the limit of the HF region (LVHF). Notice in Figure 1 the sharp filtering at the edge of FSK...
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Swedish Defence, unid datalink protocol over MS-110A
The analysis concerns short transmissions monitored on 3824.0 KHz/USB within the 80mt Ham Band (1) thanks to SM1OTX Airspy HF+ in Sweden and OZ1AEF KiwiSDR in Denmark. According to my observations, at...
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unid PSK8 waveform
Unid PSK8 2400Bd serial waveform heard on 6987.0 KHz/USB, data transfers appear to occur in ARQ mode (Figure 1). Fig. 1The larger signal' segments have strong 66.66ms ACF spikes that make a 160-symbol...
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ISR Navy PSK8/2400Bd (datalink protocol)
Just some notes about the datalink protocol used by Israeli Navy (IDF) and their proprietary PSK8/2400Bd modem.The datalink protocol transfers data using "Tx-Frames" formats consisting of 6, 12 and 18...
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QPSK (Link-22) & PSK8 (unid) bursts
Since some days on 7907.0 KHz/USB, starting in the morning, it's possible to hear long sessions of 2400Bd burst signals which use different modulations and ways. Signal "A" in Figure 1 consists of...
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MIL 188-220 App.D (Combat Net Radio) compliant transmissions in HF band
MIL-STD 188-220 suite (here MS-220D) was developed to meet the requirements for mobile Combat Net Radios (CNR) such as SINCGARS (Single Ground and Airborne Radio System) or more recent JTRS (Joint...
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KW-46 secured fleet broadcast over S-4285 in ISB mode (Humpty Doo, MHFCS)
Interesting fleet broadcast from the MHFCS (Modernised High Frequency Communications System) site in Humpty Doo, Northern Territory - Australia. The transmissions use STANAG-4285 600bps/L in ISB mode...
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(unid) synchronous transfer protocol over MS-110A & FED-1052 DLP
Durings the last few days I have monitored the frequency 7762.0 KHz/U and collected very interesting recordings of transmissions regarding a (possible) synchronous transfer protocol which sits at a...
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3G-HF Fast Traffic Manager (FTM) at work
This sample provides an example of the use of 3G-HF (STANAG-4538) Fast Traffic Manager (FTM) protocol, which is sometimes referred to as simply FLSU (Fast Link SetUp). More precisely, FLSU is used to...
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CIS MFSK-33 (here:15+∅+17), likely a "Serdolik" multimode waveform
Fig. 1 - "Serdolik" multimode waveformThe MFSK segments have the usual 40Bd and 40Hz (channels separation) values which are typical of the Serdolik waveforms family: a long-range radio system used by...
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unid datalink protocol(s) over a PSK8 ST and STANAG-4539 (Thales? L3Harris?)
A few days ago I came across some transmissions that caught my attention for at least three good reasons:1. the frequency used, i.e. 7312.7 KHz/USB, within the 42 meter broadcast band;2. the use of...
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unid datalink protocol(s) over a PSK8 ST and STANAG-4539 (2)
I had the opportunity to record other transmissions on 3712.70 KHz/USB and - also following the comment of my friend KarapuZ - I can state with reasonable certainty that the waveforms analyzed in the...
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French AF AWACS comms using MS-110A
I recently recorded some transmissions of the French Air Force (FAF), more precisely traffic between the Boeing E-3F Sentry 202 aircraft (ALE address 202E3F) & its home, ie the E-3F Main Operating...
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a difficult signal
Sometimes it may happens to come across signals for which - unless of know it a priori - it is difficult to correctly define the used modulation; it's the case of the so-called "semi-modes", where...
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Akula always reserves surprises...
A few days ago a friend of mine sent me some recordings of a serie of FSK bursts which had the same keying speed and shift (500Bd/1000Hz) as the "Akula" waveform but which differed due to the lack of...
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Japanese Navy fleet broadcast, a review of the "Japanese Slot Machine" (I)
Japanese Maritime Self-Defence Forces (JMSDF) HF Fleet Broadcast, also known as the "Japanese Slot Machine", heard with data payloads on 8312.50 KHz/USB using a remote KiwiSDR located in Azumino-city,...
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