ARLA/CLUSTER: FSQ - Fast Simple QSO: Novo modo digital com codigo fonte aberto

[João Costa > CT1FBF]

 New open source data mode FSQ

Con Wassilieff ZL2AFP has developed a new fast simple chat data mode
for use on HF and VHF

FSQ is a Fast Simple QSO mode for MF/HF. It works well under NVIS and
sunrise/sunset conditions on the lower bands, and also works well for
short skip on higher bands. It can also be used on VHF FM, and clearly
has a much wider useful range of operating conditions that other more
conventional digital modes. Sending speed can be varied between 20 and
60 WPM.

FSQ is designed for simple but effective 'Chat' operation, rather like
phone text messaging or Skype™ chat; fast and easy to use. You don't
use 'overs' as you would with a conventional digital or voice mode. It
is highly suited to net operation. You just type a sentence and press
Enter.

An important factor in the design of FSQ is that no synchronising
process is required to locate and decode the received characters. Lack
of sync means that reception is much less influenced by propagation
timing changes that affect almost all other modes, since timing is
quite unimportant; it almost completely eliminates impulse noise
disruption; and it also contributes to very fast acquisition of the
signal (decoding reliably within one symbol of start of reception).
Fast acquisition removes the need for addition of extra idle
characters at the start of transmission, and this leads to a very
slick system. Add high resistance to QRM and QRN, thanks to the low
baud rate, and you have a system so robust that it does not need error
correction.

Sensitivity is believed to be about -13 dB SNR at 6 baud, and -16 dB
SNR at 3 baud. That's about 10dB better and several times faster than
12 WPM Morse.

FSQ is NOT compatible in any way with EXChat or DominoEX. While also a
Chat mode, it uses a completely new and revolutionary protocol.

Read more about FSQ at
http://www.qsl.net/zl1bpu/MFSK/FSQweb.htm

Direct download link
http://www.qsl.net/zl1bpu/SOFT/FSQCALL.zip