The thread that has been running about BPSK / QRS CW covers the technical
issues, but I sense there is an assumption that BPSK as per AFRICA/COHERENT
by Bill de Carle and the PSK31 (and it's variants) by G3PLX are radically
different implementations of PSK.
The purpose of this note is to stimulate a discussion of the differences
between the two systems.
For starters, PSK31 was defined by Peter Martinez, G3PLX, as being for
"keyboard to keyboard" types of applications. This is a new system
implementation of what we used to call "Green Keys" type of teletype
operation. The basic tenet as I understand it is for keyboard to keyboard
QSO's over the radio.
In the very opposite sense, C-BPSK as implemented in Coherent/Africa by Bill
de Carle, VE2IQ, will accommodate users who wish to use the package for
Keyboard to Keyboard, but the REAL PURPOSE of the programs is to get down
and dig a signal out of the mud, to do so with the single determination of
finding a signal and using every mathematical resource available to pull
that signal out of the noise.
The application of these packages should take into consideration the job
that is desired to be done. Using PSK31 to work over the North Atlantic on
136 would be a gross misapplication of the software unless there was certain
knowledge that the task can in fact be accomplished within a reasonable time
period. On the other hand Coherent/Africa will patiently wait for months
or even years with a minimum of demands on the users for a signal to pop out
of the noise.
The technical discussion are enlightening and really great but the
discussion also needs to consider what the objectives are for the experiment
that the user desires to perform. It is obvious to me that there is a need
to identify what applications can make the best use of the existing software
programs such as QRS CW, PSK31, and Coherent/Africa. If careful attention
is given to the details of the system requirements then at the end of the
day the software system developers will have new opportunities to make their
systems stay on the leading edge of performance.
Larry
VA3LK
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