FST4W
From Signal Identification Wiki
FST4W is an amateur radio digital protocol designed particularly for the LF and MF bands, for quasi-beacon transmissions of WSPR-style messages. FST4W uses 4-GFSKGaussian Frequency-Shift Keying modulation and offers T/R sequence lengths of 120, 300, 900, and 1800 seconds.
FST4W do not require the strict, independent time synchronization and phase locking of modes like EbNaut. FST4W-120 SNR threshold is about 1.4 dBThe decibel (dB) is a logarithmic unit used to express the ratio of two values of a physical quantity, here the strength of a received signal. lower than WSPR.
Frequencies[edit]
- 136 kHzKiloHertz (kHz) 10^3 Hz
- 474.2 kHzKiloHertz (kHz) 10^3 Hz
- 1.8366 MHzMegaHertz (MHz) 10^6 Hz
T/R period (s) | Symbol length (s) | Tone spacing (HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).) | Bandwidth (HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).) | SNR (dBThe decibel (dB) is a logarithmic unit used to express the ratio of two values of a physical quantity, here the strength of a received signal.) |
---|---|---|---|---|
120 | 0.683 | 1.46 | 5.9 | -32.8 |
300 | 1.792 | 0.56 | 2.2 | -36.8 |
900 | 5.547 | 0.18 | 0.72 | -41.7 |
1800 | 11.200 | 0.089 | 0.36 | -44.8 |