From ylindqvist@rwth-aachen.de Fri Feb 04 22:02:21 1994 Path: ashpoly!cascade!bigsur!rwth-aachen!ylindqvist From: ylindqvist@rwth-aachen.de (Yuki Lindqvist) Newsgroups: comp.dsp Subject: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Feb04.220221.1731@rwth-aachen.de> Date: Fri, 04 Feb 1994 22:02:21 GMT Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: WinVN 0.99.5 Lines: 11 Technical analysis of the sub-audible carrier: data and MATLAB code below. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. 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? -- Yuki Lindqvist "Hold for relay." Sun SparcStation 20 / FreeBSD 2.1 From dpetrov@pacbell.net Sat Feb 05 11:06:21 1994 Path: ashpoly!cascade!transat!ukc!fennimore!pacbell!dpetrov From: dpetrov@pacbell.net (Dmitri Petrov) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Feb05.110621.2708@pacbell.net> Date: Sat, 05 Feb 1994 11:06:21 GMT References: <1994Feb04.220221.1731@rwth-aachen.de> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Feb04.220221.1731@rwth-aachen.de>, ylindqvist@rwth-aachen.de (Yuki Lindqvist) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. 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. -- Dmitri Petrov SupraFAXModem 28.8 @ 19,200 bps "Do not worship the copy."