From jnakamura@uni-hamburg.de Thu Jan 12 21:40:39 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!uni-hamburg!jnakamura From: jnakamura@uni-hamburg.de (Jens Nakamura) Newsgroups: comp.dsp Subject: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jan12.214039.4490@uni-hamburg.de> Date: Thu, 12 Jan 1995 21:40:39 GMT Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: TIN [version 1.2 PL2] Lines: 10 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. I've uploaded the C source for my decimation and bandpass filter to ftp.ashford-poly.edu. -- Jens Nakamura -- Universität Hamburg Fachbereich Informatik "In theory there is no difference between theory and practice." From feriksson@cmu.edu Sat Jan 14 15:42:39 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!cmu!feriksson From: feriksson@cmu.edu (Freya Eriksson) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jan14.154239.2115@cmu.edu> Date: Sat, 14 Jan 1995 15:42:39 GMT References: <1995Jan12.214039.4490@uni-hamburg.de> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 11 In article <1995Jan12.214039.4490@uni-hamburg.de>, jnakamura@uni-hamburg.de (Jens Nakamura) 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. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Freya Eriksson *PLONK* filter active for trolls. Atari Falcon 030 - NetBSD 1.0 From dduarte@cmu.edu Sun Jan 15 16:02:39 1995 Path: ashpoly!cascade!mxgate!coyoacan!cmu!dduarte From: dduarte@cmu.edu (Diego Duarte) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jan15.160239.9347@cmu.edu> Date: Sun, 15 Jan 1995 16:02:39 GMT References: <1995Jan12.214039.4490@uni-hamburg.de> <1995Jan14.154239.2115@cmu.edu> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Jan14.154239.2115@cmu.edu>, feriksson@cmu.edu (Freya Eriksson) writes: > If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. > My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Diego Duarte Tape trading list upon request. SASE required for international mail. From msuzuki@kiae.su Mon Jan 16 13:01:39 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!kiae!msuzuki From: msuzuki@kiae.su (Mei Suzuki) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jan16.130139.9915@kiae.su> Date: Mon, 16 Jan 1995 13:01:39 GMT References: <1995Jan12.214039.4490@uni-hamburg.de> <1995Jan14.154239.2115@cmu.edu> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1995Jan14.154239.2115@cmu.edu>, feriksson@cmu.edu (Freya Eriksson) writes: > If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. 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. -- Mei Suzuki -- Kurchatov Institute of Atomic Energy, Moscow "5 sigma is a discovery. 7 is a question." From lito@tum.de Mon Jan 16 17:29:39 1995 Path: ashpoly!cascade!transat!ukc!fennimore!tum!lito From: lito@tum.de (Lucia Ito) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jan16.172939.2208@tum.de> Date: Mon, 16 Jan 1995 17:29:39 GMT References: <1995Jan12.214039.4490@uni-hamburg.de> <1995Jan14.154239.2115@cmu.edu> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1995Jan14.154239.2115@cmu.edu>, feriksson@cmu.edu (Freya Eriksson) writes: > If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. > My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! Prof. Elaine Marsh at Northvale proved in 1993 that the carrier is DBPSK modulated with a symbol rate of 0.71 Hz. -- Lucia Ito *PLONK* filter active for trolls. Macintosh IIfx - NetBSD 1.0