:doctype: manpage
:man source: AsciiDoc
:man version: {VERSION}
:man manual: WSJT-X Manual
= fst4sim(1)

== NAME

fst4sim, qra64sim - Generate simulated QRA64, FST4, and FST4W mode signals.

== SYNOPSIS

*qra64sim* msg A-E Nsigs fDop DT Nfiles SNR

*fst4sim* msg TRsec f0 DT h fDop del Nfiles SNR W

== DESCRIPTION

*fst4sim* can be used to generate FST4 and FST4W signals with
user-specified message content, mode parameters, and SNR values.

== ARGS

*msg*::

 A valid QRA64, FST4, or FST4W message enclosed in quotation marks.

*A-E*::

QRA64 sub-mode designator.

*Nsigs*::

 Number of signals to simulate, distributed even across a 2000 Hz
 bandwidth.
 
*TRsec*::

 A valid T/R period duration (s).

*f0*::

 Integer signal frequency offset (Hz).

*DT*::

 Decimal signal time offset (s).

*h*::

 A valid modulation index.

*fDop*::

 Decimal Doppler frequency spread (Hz).

*del*::

 Decimal Watterson model delay (ms).

*nfiles*::

 Number of files to generate.

*snr*::

 Add Guassian noise to simulate SNR in 2500 Hz bandwidth.

*W*::

 Hint to break ties between ambiguous messages '0' as 77-bit (FST4),
 '1' as 50-bit (FST4W).

Generated files are 12000 Hz sample rate, 16-bit unsigned format, mono
PCM .WAV files suitable for replay using WSJT-X either vie the GUI
*wsjtx*(1) or using the command line slow mode decoder *jt9*(1). Files
are named 000000_nnnnnn.wav (000000_nnnn.wav for QRA64), where
'nnnnnn' or 'nnnn' increments from zero.

== AUTHOR

Joe Taylor, K1JT.

== COPYING

*fcal* is Copyright (C) 2001 - 2019 by Joseph H.  Taylor, Jr., K1JT,
with contributions from additional authors.  WSJT-X is Open Source
software, licensed under the GNU General Public License (GPLv3).

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.