Link-11 (UHF)

Link-11 | Link-11 (UHFUltra High Frequency (300-3000 MHz))

Link-11 (UHF)

Frequencies	225 MHz,399.975 MHz
Frequency Range	225 MHz - 399.975 MHz
Mode	NFM
Modulation	PSK
ACF	—
Emission Designator	—
Bandwidth	30 kHz
Location	Worldwide
Short Description	This is the UHF band variant of Link-11, which is transmitted on a FM carrier. The FM-demodulated baseband is identical to the HF Link-11 waveform.
I/Q Raw Recording	Download file
Audio Sample

This is the UHFUltra High Frequency (300-3000 MHz) band variant of Link-11, which is transmitted on a FMFrequency Modulation carrier. The FMFrequency Modulation-demodulated baseband is identical to the original Link-11 waveform used on MFMedium Frequency (300-3000 kHz) and HFHigh Frequency (3-30 MHz) bands. See the Link-11 page for in-depth details on the underlying waveform characteristics.

Characteristics

Link-11 UHFUltra High Frequency (300-3000 MHz) has many of the same characteristics as the original underlying Link-11 waveform, including the characteristic sound pattern. The UHFUltra High Frequency (300-3000 MHz) variant, which is FMFrequency Modulation-modulated, is about 30 kHzKiloHertz (kHz) 10^3 Hz wide in bandwidth. Each of the short ACK/ARQAutomatic Repeat reQuestAutomatic Repeat Query bursts are about 125ms long, with the data payload duration being variable.

When FMFrequency Modulation-demodulated, the waveform is equivalent to that of Link-11 on the MFMedium Frequency (300-3000 kHz) and HFHigh Frequency (3-30 MHz) bands.

Samples

• This recording was captured being transmitted from a NATO AWACS aircraft on 339.550 MHzMegaHertz (MHz) 10^6 Hz over Poland on December 19, 2016. UHFUltra High Frequency (300-3000 MHz) use of Link-11 suggests line-of-sight operations. This was a FMFrequency Modulation-modulated Link-11 CLEW waveform.

Frequencies

For the UHFUltra High Frequency (300-3000 MHz) band, it is capable of tuning to any integral multiple of 25 kHzKiloHertz (kHz) 10^3 Hz from 225 MHzMegaHertz (MHz) 10^6 Hz to 399.975 MHzMegaHertz (MHz) 10^6 Hz.

Frequencies spotted at:

• 339.550 MHzMegaHertz (MHz) 10^6 Hz

Decoding Software

It should be noted that these packages cannot decrypt Link-11 data

Professional Equipment/Software

• go2DECODE
• go2MONITOR
• Hoka Code 300-32
• Wavecom W-Code CLEW only
• Wavecom W-Spectra CLEW only

Additional Links

• MIL-STD-188-203-1A Military Standard for Tactical Digital Information Link (TADIL-A), 1988
• Wikipedia MIL-STD-6011
• NAVAL POSTGRADUATE SCHOOL: Master's Thesis on Link 11

Additional Images

Waterfall and spectrum of FMFrequency Modulation-demodulated waveform, which is identical to that of LINK-11 HFHigh Frequency (3-30 MHz) waveform.