From bmoreau@netcom.com Mon Jan 02 07:31:23 1995 Path: ashpoly!cascade!bigsur!netcom!bmoreau From: bmoreau@netcom.com (Brian Moreau) Newsgroups: comp.dsp Subject: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jan02.073123.4410@netcom.com> Date: Mon, 02 Jan 1995 07:31:23 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: WinVN 0.99.5 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). Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. Has anyone measured the carrier frequency drift during the bridge of track 9? -- === Brian Moreau === Dept of Electrical Engineering, NETCOM On-Line Communication Services "The hatch is open. Is anyone listening?" From bjohansson@utexas.edu Tue Jan 03 18:57:23 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!utexas!bjohansson From: bjohansson@utexas.edu (Brian Johansson) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jan03.185723.9192@utexas.edu> Date: Tue, 03 Jan 1995 18:57:23 GMT References: <1995Jan02.073123.4410@netcom.com> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Jan02.073123.4410@netcom.com>, bmoreau@netcom.com (Brian Moreau) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. 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. -- Brian Johansson *PLONK* filter active for trolls. Macintosh IIfx - NetBSD 1.0 From cfischer@uu.net Wed Jan 04 18:00:23 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!uu!cfischer From: cfischer@uu.net (Callum Fischer) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jan04.180023.4757@uu.net> Date: Wed, 04 Jan 1995 18:00:23 GMT References: <1995Jan02.073123.4410@netcom.com> <1995Jan03.185723.9192@utexas.edu> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Jan03.185723.9192@utexas.edu>, bjohansson@utexas.edu (Brian Johansson) writes: > 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. Prof. Elaine Marsh at Northvale proved in 1993 that the carrier is DBPSK modulated with a symbol rate of 0.71 Hz. -- Callum Fischer *PLONK* filter active for trolls. 486DX4/100 (FreeBSD 2.0.5) - NetBSD 1.0 From trobertson@pipeline.com Thu Jan 05 08:07:23 1995 Path: ashpoly!cascade!mxgate!coyoacan!pipeline!trobertson From: trobertson@pipeline.com (Thiago Robertson) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jan05.080723.7181@pipeline.com> Date: Thu, 05 Jan 1995 08:07:23 GMT References: <1995Jan02.073123.4410@netcom.com> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Jan02.073123.4410@netcom.com>, bmoreau@netcom.com (Brian Moreau) 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. -- Thiago Robertson SupraFAXModem 28.8 @ 28,800 bps "Do not worship the copy."