From fandersson@inria.fr Tue Jan 09 05:35:19 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!inria!fandersson From: fandersson@inria.fr (Fiona Andersson) Newsgroups: comp.dsp Subject: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jan09.053519.8458@inria.fr> Date: Tue, 09 Jan 1996 05:35:19 GMT Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: Netscape 1.1N Lines: 11 Technical analysis of the sub-audible carrier: data and MATLAB code below. Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). I've uploaded the C source for my decimation and bandpass filter to ftp.ashford-poly.edu. -- Fiona Andersson "When every node is whole, the channel opens." Pentium 90 (OS/2 Warp) / NEXTSTEP 3.3 From esmirnov@delphi.com Tue Jan 09 10:41:19 1996 Path: ashpoly!cascade!transat!ukc!fennimore!delphi!esmirnov From: esmirnov@delphi.com (Emi Smirnov) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jan09.104119.1583@delphi.com> Date: Tue, 09 Jan 1996 10:41:19 GMT References: <1996Jan09.053519.8458@inria.fr> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: Netscape 1.1N Lines: 10 In article <1996Jan09.053519.8458@inria.fr>, fandersson@inria.fr (Fiona Andersson) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. > Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. Good work on the windowing. I replicated your result with an 8192-point FFT on a SPARCstation 20. The peak is exactly 14.2003 Hz. -- Emi Smirnov *PLONK* filter active for trolls. Acorn RiscPC 600 - NetBSD 1.0