Abstract

Atmospheric turbulence causes random fading in any open-air optical communication channel. When the transmitted message is in the form of a block code, a binary union decoding system consisting of one storage register can be used to enhance the reliability of this type of fading channel. To illustrate the effectiveness of the binary union decoder, we compare probabilities of detecting one word out of N + 1 received words for both a binary union decoder and a simple word recognition decoder system. Finally, the binary union decoder is analyzed for three different fading conditions of the channel corresponding to conditions of atmospheric turbulence typical of weak, moderate, and superstrong scattering. Our findings show that the worst channel conditions for an optical communication system exist when the turbulence is moderate.

© 1983 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. R. L. Phillips, L. C. Andrews, J. Opt. Soc. Am. 71, 1440 (1981).
    [CrossRef]
  2. G. R. Ochs, R. R. Bergman, J. R. Snyder, J. Opt. Soc. Am. 59, 231 (1969).
    [CrossRef]
  3. J. R. Dunphy, J. R. Kerr, J. Opt. Soc. Am. 63, 981 (1973).
    [CrossRef]
  4. G. Parry, P. N. Pusey, J. Opt. Soc. Am. 69, 796 (1979).
    [CrossRef]
  5. G. Parry, Opt. Acta 28, 715 (1981).
    [CrossRef]
  6. R. L. Phillips, L. C. Andrews, J. Opt. Soc. Am. 72, 864 (1982).
    [CrossRef]

1982 (1)

1981 (2)

1979 (1)

1973 (1)

1969 (1)

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (4)

Fig. 1
Fig. 1

Block diagram of binary decoder.

Fig. 2
Fig. 2

Probability of detection curves for the binary union decoder (solid curves) and the word recognition decoder (dotted curves) corresponding to N = 4 or N = 8, and w = 6.

Fig. 3
Fig. 3

Normalized variance of the intensity as a function of threshold for three different conditions of atmospheric turbulence.

Fig. 4
Fig. 4

Probability of detection curves for the binary union decoder and word recognition decoder as a function of threshold for three different conditions of atmospheric turbulence; N = 4 and w = 6.

Equations (16)

Equations on this page are rendered with MathJax. Learn more.

α i j = a i , j a i + 1 , j , 1 i N , 1 j w .
P BUD = P ( i = 1 N A i ) = S 1 S 2 + + ( 1 ) N + 1 S N ,
S 1 = i = 1 N P ( A i ) , S 2 = i , j = 1 i j N P ( A i A j ) , S m = i , , k = 1 i k N P ( A i A k m terms ) .
P ( α i j ) = P ( a i , j ) + P ( a i + 1 , j ) P ( a i , j ) P ( a i + 1 , j ) = 1 ( 1 p ) 2 ,
P ( A i ) = [ 1 ( 1 p ) 2 ] w .
S 1 = N [ 1 ( 1 p ) 2 ] w = ( N 1 ) [ 1 ( 1 p ) ( 1 p ) ] w ,
P ( A i A j ) = k = 1 w P ( α i k α j k ) .
P ( α i k α j k ) = P ( α i k ) + P ( α j k ) P ( α i k α j k ) = 2 [ 1 ( 1 p ) 2 ] ( 3 p 3 p 2 + p 3 ) = 1 ( 1 p ) ( 1 p 2 ) ,
P ( A i A j ) = [ 1 ( 1 p ) ( 1 p 2 ) ] w ,
S 2 = ( N 2 ) [ 1 ( 1 p ) ( 1 p 2 ) ] w .
S m = ( N m ) [ 1 ( 1 p ) ( 1 p m ) ] w , m = 1 , 2 , , N ,
P BUD = m = 1 N ( 1 ) m + 1 ( N m ) [ 1 ( 1 p ) ( 1 p m ) ] w .
P word = p w ,
P WRD = 1 ( 1 p w ) N + 1 .
P BUD = m = 1 N ( 1 ) m + 1 ( N m ) { [ 1 ( 1 p ) ( 1 p m ) ] × [ 1 ( 1 q ) ( 1 q m ) ] } w / 2 ,
P WRD = 1 [ 1 ( p q ) w / 2 ] N + 1 .

Metrics