At 10:54 AM 8/31/2007, Scott Wilson wrote:
I have a question regarding software doppler correction - in particular when using linear satellites.
Hi Scott,
I agree with everything Paul Williamson posted and especially to read his old essay that is on the subject.
After that is all clear, you can get a huge head start on software by reading my paper from the 1997 AMSAT-NA Space Symposium; "An Object Oriented Approach to Automatic Radio Tuning." It has a detailed analysis and a high-level software design that is independent of operating system or tracking program.
Next, you can download all of the C++ source code for a working implementation of this (InstantTune) from the AMSAT web site at:
http://www.amsat.org/amsat/ftp/software/PC/radio-control/itune110.zip
The source code is in the file SRC110.ZIP and there is a source code guide in the file ITUNESRC.TXT. This software includes drivers for most radios including "dumb" mic-button radios. The user manual is in ITUNE110.DOC and describes the features of the software and how to use it.
The vast majority of the source code is operating system and tracking program independent. The hardware drivers are not needed under LINUX or Windows and the command interface would need to be re-written for your favorite tracking program/OS.
Note that this software is free and open source with no license so feel free to use whatever is useful to you.
If you have any questions after looking over this stuff, please feel free to email me.
Best of luck with your project!
73, Tony AA2TX