From jperez@earthlink.net Sun Mar 06 19:04:53 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!earthlink!jperez From: jperez@earthlink.net (Joachim Pérez) Newsgroups: comp.dsp Subject: Question: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Mar06.190453.2583@earthlink.net> Date: Sun, 06 Mar 1994 19:04:53 GMT Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. I've uploaded the C source for my decimation and bandpass filter to ftp.ashford-poly.edu. -- === Joachim Pérez === Dept of Electrical Engineering, EarthLink Network "Do not worship the copy." From lduarte@purdue.edu Tue Mar 08 14:59:53 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!purdue!lduarte From: lduarte@purdue.edu (Lars Duarte) Newsgroups: comp.dsp Subject: Re: Question: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Mar08.145953.2461@purdue.edu> Date: Tue, 08 Mar 1994 14:59:53 GMT References: <1994Mar06.190453.2583@earthlink.net> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Mar06.190453.2583@earthlink.net>, jperez@earthlink.net (Joachim Pérez) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. -- Lars Duarte *PLONK* filter active for trolls. 486DX4/100 (FreeBSD 2.0.5) - NetBSD 1.0 From jdubois@illinois.edu Wed Mar 09 04:55:53 1994 Path: ashpoly!cascade!bigsur!illinois!jdubois From: jdubois@illinois.edu (Ji-woo Dubois) Newsgroups: comp.dsp Subject: Re: Question: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Mar09.045553.8010@illinois.edu> Date: Wed, 09 Mar 1994 04:55:53 GMT References: <1994Mar06.190453.2583@earthlink.net> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N Lines: 12 In article <1994Mar06.190453.2583@earthlink.net>, jperez@earthlink.net (Joachim Pérez) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. > With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). 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. If you are posting from AOL, please read RFC 1036 before posting again. -- === Ji-woo Dubois === Dept of Electrical Engineering, University of Illinois Urbana-Champaign "There are 14 nodes and only 10 countries. Count again." From aito@u-tokyo.ac.jp Wed Mar 09 09:29:53 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!u-tokyo!aito From: aito@u-tokyo.ac.jp (Amy Ito) Newsgroups: comp.dsp Subject: Re: Question: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Mar09.092953.5043@u-tokyo.ac.jp> Date: Wed, 09 Mar 1994 09:29:53 GMT References: <1994Mar06.190453.2583@earthlink.net> Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: Netscape 1.1N Lines: 11 In article <1994Mar06.190453.2583@earthlink.net>, jperez@earthlink.net (Joachim Pérez) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. Prof. Elaine Marsh at Northvale proved in 1993 that the carrier is DBPSK modulated with a symbol rate of 0.71 Hz. Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. -- === Amy Ito === Dept of Electrical Engineering, University of Tokyo Department of Information Science "Do not worship the copy." From agirard@unam.mx Fri Mar 11 12:54:53 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!unam!agirard From: agirard@unam.mx (Anja Girard) Newsgroups: comp.dsp Subject: Re: Question: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Mar11.125453.9243@unam.mx> Date: Fri, 11 Mar 1994 12:54:53 GMT References: <1994Mar06.190453.2583@earthlink.net> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Mar06.190453.2583@earthlink.net>, jperez@earthlink.net (Joachim Pérez) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. > With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). You're overlooking tape wow and flutter. A Revox B77 has at least 0.05% speed drift, which would smear a 14 Hz line across several bins. -- === Anja Girard === Dept of Electrical Engineering, Universidad Nacional Autónoma de México (DGSCA) "Do not worship the copy."