demodulation question

*To*: mathgroup at christensen.cybernetics.net*Subject*: [mg514] demodulation question*From*: yverband at vnet3.vub.ac.be (Yves Verbandt)*Date*: Tue, 7 Mar 95 07:38:51 +0100

Dear Mathgroupers, I have some measured curves which following the model have the following form : s(x) = f(x)*cos(k*x) where k is a constant and f(x) is a slowly varying function. Because there is coniderable noise on the measurements the cosine is not very regular. Does anyone have an idea how to extract f(x)? I tried the NonlinearFit package and this was not very successfull! Thank you very much for you kind help. Yves Verbandt ********************************************** Yves Verbandt Vrije Universiteit Brussel Applied Physics Department ALNA-TW, Pleinlaan 2, B-1050 Brussel, BELGIUM tel. +-32-2-629.36.13 fax. +-32-2-629.34.50 Internet yverband at vnet3.vub.ac.be **********************************************