From teriksson@illinois.edu Sun Jun 11 18:35:41 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!illinois!teriksson From: teriksson@illinois.edu (Takeshi Eriksson) Newsgroups: comp.dsp Subject: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jun11.183541.1015@illinois.edu> Date: Sun, 11 Jun 1995 18:35:41 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N Lines: 11 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. 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. Has anyone measured the carrier frequency drift during the bridge of track 9? -- === Takeshi Eriksson === Dept of Electrical Engineering, University of Illinois Urbana-Champaign "The hatch is open. Is anyone listening?" From rduarte@cam.ac.uk Tue Jun 13 16:22:41 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!cam!rduarte From: rduarte@cam.ac.uk (Rodrigo Duarte) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jun13.162241.5269@cam.ac.uk> Date: Tue, 13 Jun 1995 16:22:41 GMT References: <1995Jun11.183541.1015@illinois.edu> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Jun11.183541.1015@illinois.edu>, teriksson@illinois.edu (Takeshi Eriksson) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. -- Rodrigo Duarte "Hardware is temporary. The signal survives." Amiga 1200 (Blizzard 030/50) / FreeBSD 2.1