Link-11 (UHF)

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

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

Frequencies	225 MHzMegaHertz (MHz) 10^6 Hz225,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). 225,000 kHzKiloHertz (kHz) 10^3 Hz,399.975 MHzMegaHertz (MHz) 10^6 Hz399,975,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). 399,975 kHzKiloHertz (kHz) 10^3 Hz225,000 kHzKiloHertz (kHz) 10^3 Hz 225 MHzMegaHertz (MHz) 10^6 Hz 399,975 kHzKiloHertz (kHz) 10^3 Hz 399.975 MHzMegaHertz (MHz) 10^6 Hz
Frequency Range	225 MHzMegaHertz (MHz) 10^6 Hz225,000,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). 225,000 kHzKiloHertz (kHz) 10^3 Hz - 399.975 MHzMegaHertz (MHz) 10^6 Hz399,975,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). 399,975 kHzKiloHertz (kHz) 10^3 Hz
Mode	NFMNarrowband Frequency Modulation
Modulation	PSKPhase-Shift Keying
ACFAutoCorrelation Function	—
Bandwidth	30 kHzKiloHertz (kHz) 10^3 Hz30,000 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). 0.03 MHzMegaHertz (MHz) 10^6 Hz 30 kHzKiloHertz (kHz) 10^3 Hz 0.03 MHzMegaHertz (MHz) 10^6 Hz 30 kHzKiloHertz (kHz) 10^3 Hz 0.03 MHzMegaHertz (MHz) 10^6 Hz
Location	Worldwide
Short Description	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 HFHigh Frequency (3-30 MHz) 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.