Least-Squares Spectral Analysis (LSSA) is a spectral analysis approach based on least-squares. It was originally designed by Petr Vanícek, in 1959, and it has gone through several improvements since then.
In this site you find a discussion on the theoretical basis of LSSA and advantages (and similarities) over other approaches, and a list of the literature related to it, dealing with both theory and applications. You also find the source code of its last version and a sample data set all for free downloading. The source code is written in FORTRAN and we believe that any compiler can be used to run it. A User's Manual is also available.
LSSA is free for you to use. If you do, please make a reference. We suggest:
Vaníček, P. (1971). "Further development and properties of the spectral analysis by least-squares." Astrophysics and Space Sciences, Vol. 12, 10–33.
If you need any additional information, please e-mail Prof. Marcelo Santos .