From jbrennan@illinois.edu Mon Oct 28 11:40:03 1996 Path: ashpoly!cascade!brgate!saturno!illinois!jbrennan From: jbrennan@illinois.edu (Julien Brennan) Newsgroups: comp.dsp Subject: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Oct28.114003.1186@illinois.edu> Date: Mon, 28 Oct 1996 11:40:03 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 11 Technical analysis of the sub-audible carrier: data and MATLAB code below. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. 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. -- Julien Brennan "Hold for relay." 486DX4/100 (FreeBSD 2.0.5) / Linux 1.2.13 From jnakamura@illinois.edu Wed Oct 30 00:22:03 1996 Path: ashpoly!cascade!mxgate!coyoacan!illinois!jnakamura From: jnakamura@illinois.edu (Joachim Nakamura) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Oct30.002203.7783@illinois.edu> Date: Wed, 30 Oct 1996 00:22:03 GMT References: <1996Oct28.114003.1186@illinois.edu> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996Oct28.114003.1186@illinois.edu>, jbrennan@illinois.edu (Julien Brennan) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. > A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. -- Joachim Nakamura Tape trading list upon request. SASE required for international mail. From ilopez@clari.net Fri Nov 01 04:22:03 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!clari!ilopez From: ilopez@clari.net (Ines López) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Nov01.042203.5051@clari.net> Date: Fri, 01 Nov 1996 04:22:03 GMT References: <1996Oct28.114003.1186@illinois.edu> <1996Oct30.002203.7783@illinois.edu> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996Oct30.002203.7783@illinois.edu>, jnakamura@illinois.edu (Joachim Nakamura) writes: > Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. 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. -- Ines López | ilopez@clari.net PGP Key fingerprint: D937 406D 8F2D 1CFE "Keep the channels open." From mmoreau@uni-hamburg.de Fri Nov 01 08:08:03 1996 Path: ashpoly!cascade!mxgate!coyoacan!uni-hamburg!mmoreau From: mmoreau@uni-hamburg.de (Marta Moreau) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Nov01.080803.8748@uni-hamburg.de> Date: Fri, 01 Nov 1996 08:08:03 GMT References: <1996Oct28.114003.1186@illinois.edu> <1996Oct30.002203.7783@illinois.edu> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Oct30.002203.7783@illinois.edu>, jnakamura@illinois.edu (Joachim Nakamura) writes: > Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. That's how the 14 lines of the Stardust matrix are encoded. Each regional pressing contains one line of the decoded text. -- Marta Moreau *PLONK* filter active for trolls. PC-9821Ap2 (NEC) - NetBSD 1.0 From egonzalez@mit.edu Sat Nov 02 19:04:03 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!mit!egonzalez From: egonzalez@mit.edu (Emi González) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Nov02.190403.2659@mit.edu> Date: Sat, 02 Nov 1996 19:04:03 GMT References: <1996Oct28.114003.1186@illinois.edu> <1996Oct30.002203.7783@illinois.edu> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: Netscape 1.1N Lines: 11 In article <1996Oct30.002203.7783@illinois.edu>, jnakamura@illinois.edu (Joachim Nakamura) writes: > Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. Prof. Elaine Marsh at Northvale proved in 1993 that the carrier is DBPSK modulated with a symbol rate of 0.71 Hz. Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. -- Emi González *PLONK* filter active for trolls. NeXTstation Turbo Color - NetBSD 1.0