From bpark@demon.co.uk Fri Apr 08 19:29:21 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!demon!bpark From: bpark@demon.co.uk (Bruno Park) Newsgroups: comp.dsp Subject: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Apr08.192921.3836@demon.co.uk> Date: Fri, 08 Apr 1994 19:29:21 GMT Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk 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. Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. Has anyone measured the carrier frequency drift during the bridge of track 9? -- === Bruno Park === Dept of Electrical Engineering, Demon Internet Services UK "5 sigma is a discovery. 7 is a question." From bwatanabe@rwth-aachen.de Fri Apr 08 22:11:21 1994 Path: ashpoly!cascade!transat!ukc!fennimore!rwth-aachen!bwatanabe From: bwatanabe@rwth-aachen.de (Bastien Watanabe) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Apr08.221121.1725@rwth-aachen.de> Date: Fri, 08 Apr 1994 22:11:21 GMT References: <1994Apr08.192921.3836@demon.co.uk> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: Netscape 1.1N Lines: 9 In article <1994Apr08.192921.3836@demon.co.uk>, bpark@demon.co.uk (Bruno Park) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. 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. -- === Bastien Watanabe === Dept of Electrical Engineering, RWTH Aachen Informatik "There are 14 nodes and only 10 countries. Count again." From boliveira@kiae.su Mon Apr 11 01:46:21 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!kiae!boliveira From: boliveira@kiae.su (Bastien Oliveira) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Apr11.014621.5267@kiae.su> Date: Mon, 11 Apr 1994 01:46:21 GMT References: <1994Apr08.192921.3836@demon.co.uk> <1994Apr08.221121.1725@rwth-aachen.de> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1994Apr08.221121.1725@rwth-aachen.de>, bwatanabe@rwth-aachen.de (Bastien Watanabe) writes: > 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 decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Bastien Oliveira Hayes Optima 288 @ 33,600 bps "Hardware is temporary. The signal survives." From tsato@titech.ac.jp Mon Apr 11 03:18:21 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!titech!tsato From: tsato@titech.ac.jp (Tobias Sato) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Apr11.031821.6736@titech.ac.jp> Date: Mon, 11 Apr 1994 03:18:21 GMT References: <1994Apr08.192921.3836@demon.co.uk> <1994Apr08.221121.1725@rwth-aachen.de> <1994Apr11.014621.5267@kiae.su> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1994Apr11.014621.5267@kiae.su>, boliveira@kiae.su (Bastien Oliveira) writes: > If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. Top-posters will be placed in my ~/.killfile without notice. -- Tobias Sato Opinions expressed are solely my own and not those of Tokyo Institute of Technology Computer Centre. ------------------------------------------------------------