Discrimination of narrow‐band spectra. I: Spectral weights and pitch cues

1992 ◽  
Vol 92 (4) ◽  
pp. 1911-1918 ◽  
Author(s):  
Bruce G. Berg ◽  
Quang T. Nguyen ◽  
David M. Green
Keyword(s):  
Author(s):  
Felice Arena ◽  
C. Guedes Soares

The structure of wave groups in time domain depends upon the spectrum. For narrow-band spectra, if a wave with a very large height H occurs, the waves that precede and follow the highest one have height (H′ and H″ respectively) very close to H. For real spectra, the difference between H and either H′ or H″ depends on the bandwidth of the spectrum: it increases as larger is the spectrum. For bimodal spectra, the authors have shown [1] that the wave groups are strongly modified and they are function of the energy associated to the swell and to the wind wave components, as well as of the distance between the two peaks. This paper analyzes the structure of the succession of three waves, given by the high waves and the two that come before and after the highest one, in time domain. The results are analyzed, up to the second-order, for wind wave unimodal and for bimodal spectra, by comparing the height H with H′ and H″.


2001 ◽  
Vol 110 (5) ◽  
pp. 2658-2658
Author(s):  
James M. Hillenbrand ◽  
Robert A. Houde
Keyword(s):  

1991 ◽  
Vol 89 (4B) ◽  
pp. 1911-1911 ◽  
Author(s):  
Bruce G. Berg ◽  
David M. Green

2011 ◽  
Vol 7 (2) ◽  
pp. 1
Author(s):  
A. Hossen ◽  
U. Heute

 Different approaches for a high-resolution analysis of narrow-band spectra are reviewed and compared. Partial-band algorithms are proved to be zoom-FFT's. In this contribution, three new modifications of the (Subband-FFT) SB-FFT are presented. In the first modification the chirp z-transform substitutes the small FFT which calculates the band of interest. In the second modification, the idea of zero-padding the input signal is applied to the SB-FFT with pruning at both input and output. Lastly zooming a small band of frequencies using a method of transforming by parts is applied for a narrow-band signal using the adaptive SB-FFT. A newly introduced version of the subband technique is included also in this work. In this version the subband decomposition technique is combined with the linear prediction method for higher spectrum resolution. Application of the SB-FFT and its modified versions and the new version in measuring the Doppler-frequency directly and indirectly for the purpose of vehicle-speed measurements is introduced in this paper. Comparison between all methods in terms of complexity and resolution is given. A new idea of channel test is included to keep the real-time successive measurements of Doppler frequency stable and consistent as well as simple. 


Sign in / Sign up

Export Citation Format

Share Document