From bstewart@kiae.su Thu Feb 15 19:47:31 1996 Path: ashpoly!cascade!transat!ukc!fennimore!kiae!bstewart From: bstewart@kiae.su (Bill Stewart) Newsgroups: comp.dsp Subject: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Feb15.194731.4317@kiae.su> Date: Thu, 15 Feb 1996 19:47:31 GMT Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: WinVN 0.99.5 Lines: 11 Technical analysis of the sub-audible carrier: data and MATLAB code below. Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. 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? -- Bill Stewart Opinions expressed are solely my own and not those of Kurchatov Institute of Atomic Energy, Moscow. ------------------------------------------------------------ From nandersson@illinois.edu Sat Feb 17 08:28:31 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!illinois!nandersson From: nandersson@illinois.edu (Nadine Andersson) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Feb17.082831.9918@illinois.edu> Date: Sat, 17 Feb 1996 08:28:31 GMT References: <1996Feb15.194731.4317@kiae.su> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Feb15.194731.4317@kiae.su>, bstewart@kiae.su (Bill Stewart) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. > Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Nadine Andersson -- University of Illinois Urbana-Champaign "In theory there is no difference between theory and practice." From evasiliev@purdue.edu Sun Feb 18 13:30:31 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!purdue!evasiliev From: evasiliev@purdue.edu (Elaine Vasiliev) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Feb18.133031.9545@purdue.edu> Date: Sun, 18 Feb 1996 13:30:31 GMT References: <1996Feb15.194731.4317@kiae.su> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Feb15.194731.4317@kiae.su>, bstewart@kiae.su (Bill Stewart) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Elaine Vasiliev *PLONK* filter active for trolls. Sun SparcStation 20 - NetBSD 1.0 From fmoreau@utexas.edu Mon Feb 19 09:12:31 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!utexas!fmoreau From: fmoreau@utexas.edu (Fiona Moreau) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Feb19.091231.5965@utexas.edu> Date: Mon, 19 Feb 1996 09:12:31 GMT References: <1996Feb15.194731.4317@kiae.su> <1996Feb17.082831.9918@illinois.edu> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1996Feb17.082831.9918@illinois.edu>, nandersson@illinois.edu (Nadine Andersson) writes: > If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. 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. PGP Public key available via finger or upon request. -- Fiona Moreau *PLONK* filter active for trolls. Decstation 5000/200 - NetBSD 1.0 From kmuller@pipeline.com Tue Feb 20 06:39:31 1996 Path: ashpoly!cascade!brgate!saturno!pipeline!kmuller From: kmuller@pipeline.com (Kirsty Müller) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Feb20.063931.4328@pipeline.com> Date: Tue, 20 Feb 1996 06:39:31 GMT References: <1996Feb15.194731.4317@kiae.su> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1996Feb15.194731.4317@kiae.su>, bstewart@kiae.su (Bill Stewart) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. > Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. 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. -- Kirsty Müller "The hatch is open. Is anyone listening?" Mac IIci / 68882 FPU / NEXTSTEP 3.3