From jjohansson@stanford.edu Tue Aug 20 18:01:09 1996 Path: ashpoly!cascade!brgate!saturno!stanford!jjohansson From: jjohansson@stanford.edu (Julien Johansson) Newsgroups: comp.dsp Subject: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Aug20.180109.8352@stanford.edu> Date: Tue, 20 Aug 1996 18:01:09 GMT Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: WinVN 0.99.5 Lines: 11 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. 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). Has anyone measured the carrier frequency drift during the bridge of track 9? -- Julien Johansson "We don't sign stars. We build them." Amiga 3000T / Linux 1.2.13 From sfischer@inria.fr Wed Aug 21 03:41:09 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!inria!sfischer From: sfischer@inria.fr (Steve Fischer) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Aug21.034109.7936@inria.fr> Date: Wed, 21 Aug 1996 03:41:09 GMT References: <1996Aug20.180109.8352@stanford.edu> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Aug20.180109.8352@stanford.edu>, jjohansson@stanford.edu (Julien Johansson) 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. -- Steve Fischer *PLONK* filter active for trolls. Amiga 1200 (Blizzard 030/50) - NetBSD 1.0 From mramirez@berkeley.edu Wed Aug 21 17:07:09 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!berkeley!mramirez From: mramirez@berkeley.edu (Mateo Ramírez) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Aug21.170709.1694@berkeley.edu> Date: Wed, 21 Aug 1996 17:07:09 GMT References: <1996Aug20.180109.8352@stanford.edu> <1996Aug21.034109.7936@inria.fr> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Aug21.034109.7936@inria.fr>, sfischer@inria.fr (Steve Fischer) 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. Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. -- Mateo Ramírez "In theory there is no difference between theory and practice." 486DX4/100 (FreeBSD 2.0.5) / FreeBSD 2.1 From kgirard@panix.com Wed Aug 21 19:08:09 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!panix!kgirard From: kgirard@panix.com (Kirsty Girard) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Aug21.190809.9415@panix.com> Date: Wed, 21 Aug 1996 19:08:09 GMT References: <1996Aug20.180109.8352@stanford.edu> <1996Aug21.034109.7936@inria.fr> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Aug21.034109.7936@inria.fr>, sfischer@inria.fr (Steve Fischer) 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. -- Kirsty Girard *PLONK* filter active for trolls. Amiga 3000T - NetBSD 1.0 From tperez@stanford.edu Thu Aug 22 10:15:09 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!stanford!tperez From: tperez@stanford.edu (Takeshi Pérez) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Aug22.101509.5823@stanford.edu> Date: Thu, 22 Aug 1996 10:15:09 GMT References: <1996Aug20.180109.8352@stanford.edu> <1996Aug21.034109.7936@inria.fr> <1996Aug21.190809.9415@panix.com> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Aug21.190809.9415@panix.com>, kgirard@panix.com (Kirsty Girard) writes: > If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- === Takeshi Pérez === Dept of Electrical Engineering, Stanford University Computer Systems Lab "When every node is whole, the channel opens."