PMID- 11386542
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20010802
LR  - 20190515
IS  - 0001-4966 (Print)
IS  - 0001-4966 (Linking)
VI  - 109
IP  - 5 Pt 1
DP  - 2001 May
TI  - Atmospheric scattering for varying degrees of saturation and turbulent 
      intermittency.
PG  - 1871-80
AB  - Atmospheric turbulence is inherently inhomogeneous and intermittent. Short 
      periods of high activity are embedded in longer periods of relative calm. Local 
      spatial and temporal changes in sound speed associated with this intermittency 
      increase the likelihood of measuring large values of scattered acoustic signals. 
      Previous work successfully predicted the probability density functions (pdf's) of 
      fully saturated, scattered signals measured within an acoustic shadow zone 
      [Wilson et al., J. Acoust. Soc. Am. 99, 3393-3400 (1996)]. The more general case 
      of incompletely saturated scattering is considered in this paper; using the 
      Rice-Nagakami distribution a theory is developed. The predicted intensity pdf has 
      two free parameters: one to describe the degree of intermittency and a second for 
      the degree of saturation. For validation purposes, outdoor propagation 
      measurements were made over a flat, hard ground at ranges of 146-283 m and at 
      frequencies of 50-540 Hz. The saturation parameter was determined from the 
      acoustic data and also estimated from the turbulence conditions. The degree of 
      saturation increased with frequency, and measured intensity pdf's were found to 
      be in excellent agreement with the theory.
FAU - Norris, D E
AU  - Norris DE
AD  - Graduate Program in Acoustics, The Pennsylvania State University, University Park 
      16802, USA.
FAU - Wilson, D K
AU  - Wilson DK
FAU - Thomson, D W
AU  - Thomson DW
LA  - eng
PT  - Journal Article
PL  - United States
TA  - J Acoust Soc Am
JT  - The Journal of the Acoustical Society of America
JID - 7503051
EDAT- 2001/06/02 10:00
MHDA- 2001/06/02 10:01
CRDT- 2001/06/02 10:00
PHST- 2001/06/02 10:00 [pubmed]
PHST- 2001/06/02 10:01 [medline]
PHST- 2001/06/02 10:00 [entrez]
AID - 10.1121/1.1364488 [doi]
PST - ppublish
SO  - J Acoust Soc Am. 2001 May;109(5 Pt 1):1871-80. doi: 10.1121/1.1364488.