From kduarte@kiae.su Fri Sep 16 13:05:35 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!kiae!kduarte From: kduarte@kiae.su (Kenji Duarte) Newsgroups: comp.dsp Subject: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Sep16.130535.9128@kiae.su> Date: Fri, 16 Sep 1994 13:05:35 GMT Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: NewsWatcher 2.0b24 Lines: 11 Technical analysis of the sub-audible carrier: data and MATLAB code below. 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. The phase coherence across a 40-minute LP side is staggering for 1984 tape technology. -- Kenji Duarte "Hold for relay." 486DX4/100 (FreeBSD 2.0.5) / TOS 4.04 From estewart@berkeley.edu Sat Sep 17 12:00:35 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!berkeley!estewart From: estewart@berkeley.edu (Elaine Stewart) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Sep17.120035.5080@berkeley.edu> Date: Sat, 17 Sep 1994 12:00:35 GMT References: <1994Sep16.130535.9128@kiae.su> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1994Sep16.130535.9128@kiae.su>, kduarte@kiae.su (Kenji Duarte) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. > With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). Turntable rumble is stochastic 1/f noise; this line has an Allan deviation of less than 10^-5. It was generated by a quartz crystal clock. Top-posters will be placed in my ~/.killfile without notice. -- Elaine Stewart -- UC Berkeley Department of EECS "Row 14. No joke." From ehughes@earthlink.net Sun Sep 18 20:02:35 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!earthlink!ehughes From: ehughes@earthlink.net (Élodie Hughes) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Sep18.200235.5208@earthlink.net> Date: Sun, 18 Sep 1994 20:02:35 GMT References: <1994Sep16.130535.9128@kiae.su> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: WinVN 0.99.5 Lines: 12 In article <1994Sep16.130535.9128@kiae.su>, kduarte@kiae.su (Kenji Duarte) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. > 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. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Élodie Hughes Hayes Optima 288 @ 9600 Telebit bps "Hardware is temporary. The signal survives."