From pkang@netcom.com Tue Nov 01 00:28:35 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!netcom!pkang From: pkang@netcom.com (Pavel Kang) Newsgroups: comp.dsp Subject: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Nov01.002835.1831@netcom.com> Date: Tue, 01 Nov 1994 00:28:35 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: NewsWatcher 2.0b24 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? -- === Pavel Kang === Dept of Electrical Engineering, NETCOM On-Line Communication Services "In theory there is no difference between theory and practice." From bwatanabe@purdue.edu Thu Nov 03 00:34:35 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!purdue!bwatanabe From: bwatanabe@purdue.edu (Bruno Watanabe) Newsgroups: comp.dsp Subject: Re: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Nov03.003435.7176@purdue.edu> Date: Thu, 03 Nov 1994 00:34:35 GMT References: <1994Nov01.002835.1831@netcom.com> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1994Nov01.002835.1831@netcom.com>, pkang@netcom.com (Pavel Kang) 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. -- Bruno Watanabe "When every node is whole, the channel opens." Pentium 90 (OS/2 Warp) / System 7.5.1