trivial tweaks.

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/jtms3@2512 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
This commit is contained in:
Joe Taylor 2012-07-13 15:54:03 +00:00
parent 4822c93fba
commit bdd7081225
3 changed files with 10 additions and 10 deletions

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@ -4,21 +4,21 @@
1. Transmitting
Messages are sent character-by character, 6 bits plus even parity.
Message length can be one of {5 7 9 11 13 17 19 23 29}; if necessary
the message is padded with blanks to the next available length. No
other FEC is used.
Message length can be one of {5 7 9 11 13 17 19 23 29}; messages are
padded with blanks up to the next available length.
Modulation is BPSK at 2000 baud. The baseband waveform is built by
inserting a tapered sinc function for each bit, then multiplying by a
sine wave at frequency f0 = 10000.0/7 = 1428.57 Hz. Agt sample rate
48000 Hz there are 24 samples per PSK symbol and 7*24=168 samples per
character. The carrier phase increment over one character is
f0*(168/48000) = 5 cycles.
sine wave at frequency f0 = 10000.0/7 = 1428.57 Hz. At fsample=48000
Hz there are 24 samples per PSK symbol and 7*24=168 samples per
character. Carrier phase increment over one character is
f0*(168/48000) = 5 cycles, exactly.
2. Receiving
a. Pings are detected (or mouse-picked data is selected) as in
WSJT9.
WSJT9. Pings can also be detected from the squared analytic
signal. Experience may tell which is better.
b. Compute real-to-complex FFT. Zap birdies, remove frequency
components outside the range 300 - 2700 Hz, and convert to analytic

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subroutine specjtms(k,px,pxsmo,spk0,f0)
! Starting code for a JTMS3 decoder.
! Compute noise level and 2D spectra, for GUI display.
parameter (NSMAX=30*48000)
parameter (MAXFFT=8192)

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//-------------------------------------------------------------- MainWindow
//--------------------------------------------------------------- MainWindow
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include "devsetup.h"