Abstract

In order to reduce the impact of background radiation on the performance of terrestrial free-space optical systems, we propose to use two laser wavelengths and to perform the data detection at the receiver in a differential mode. We consider first the case of simple on–off keying modulation and show the performance improvement by using the proposed technique when the background noise dominates. We also extend our study to the case of pulse position modulation while proposing special signaling schemes that allow an increase in the data transmission rate at the same time as reducing the background noise effect.

© 2011 OSA

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. R. M. Gagliardi and S. Karp, Optical Communications, 2nd. ed., Wiley, 1995.
  2. W. R. Leeb, "Degradation of signal to noise ratio in optical free space data links due to background illumination," Appl. Opt. 28(15), 3443‒3449 (1989).
    [CrossRef] [PubMed]
  3. D. Rollins, J. Baars, D. Bajorins, C. Cornish, K. Fischer, and T. Wiltsey, "Background light environment for free-space optical terrestrial communications links," Proc. SPIE 4873, 99‒110 (2002).
  4. V. G. Sidorovich, "Solar background effects in wireless optical communications," Proc. SPIE 4873, 133‒142 (2002).
  5. M. A. Khalighi, N. Schwartz, N. Aitamer, and S. Bourennane, "Fading reduction by aperture averaging and spatial diversity in optical wireless systems," J. Opt. Commun. Netw. 1(6), 580‒593 (2009).
    [CrossRef]
  6. B. E. A. Saleh and M. C. Teich, Fundamentals of Photonics, Wiley, 1991.
  7. L. C. Andrews and R. L. Phillips, Laser Beam Propagation Through Random Media, 2nd. ed., SPIE Press, 2005.
  8. S. G. Wilson, M. Brandt-Pearce, Q. L. Cao, and M. Baedke, "Optical repetition MIMO transmission with multipulse PPM," IEEE Sel. Areas Commun. 23(9), 1901‒1910 (2005).
    [CrossRef]
  9. F. Xu, M. A. Khalighi, P. Caussé, and S. Bourennane, "Channel coding and time-diversity for optical wireless links," Opt. Express 17(2), 872‒887 (2009).
    [CrossRef] [PubMed]
  10. J. G. Proakis, Digital Communications, 3rd. ed., McGraw-Hill, 1995.
  11. J. Hagenauer, E. Offer, and L. Papke, "Iterative decoding of binary block and convolutional codes," IEEE Trans. Inform. Theory 42(2), 429‒445 (1996).
    [CrossRef]
  12. F. Xu, M. A. Khalighi, and S. Bourennane, "Coded PPM and multipulse PPM and iterative detection for free-space optical links," J. Opt. Commun. Netw. 1(5), 404‒415 (2009).
    [CrossRef]
  13. F. M. Davidson and X. Sun, "Gaussian approximation versus nearly exact performance analysis of optical communication systems with PPM signaling and APD receivers," IEEE Trans. Commun. 36(11), 1185‒1192 (1988).
    [CrossRef]
  14. C. C. Davis and I. I. Smolyaninov, "The effect of atmospheric turbulence on bit-error-rate in an on–off-keyed optical wireless system," Proc. SPIE 4489, 126‒137 (2002).
  15. M. A. Khalighi, Y. Jaafar, F. Xu, F. Chazallet, and S. Bourennane, "Double-laser differential signaling for suppressing background radiations in FSO systems," Queen’s 25th Biennial Symp. on Communications (QSBC), 2010, Kingston, Canada, pp. 238‒241.

2009 (3)

2005 (1)

S. G. Wilson, M. Brandt-Pearce, Q. L. Cao, and M. Baedke, "Optical repetition MIMO transmission with multipulse PPM," IEEE Sel. Areas Commun. 23(9), 1901‒1910 (2005).
[CrossRef]

2002 (3)

D. Rollins, J. Baars, D. Bajorins, C. Cornish, K. Fischer, and T. Wiltsey, "Background light environment for free-space optical terrestrial communications links," Proc. SPIE 4873, 99‒110 (2002).

V. G. Sidorovich, "Solar background effects in wireless optical communications," Proc. SPIE 4873, 133‒142 (2002).

C. C. Davis and I. I. Smolyaninov, "The effect of atmospheric turbulence on bit-error-rate in an on–off-keyed optical wireless system," Proc. SPIE 4489, 126‒137 (2002).

1996 (1)

J. Hagenauer, E. Offer, and L. Papke, "Iterative decoding of binary block and convolutional codes," IEEE Trans. Inform. Theory 42(2), 429‒445 (1996).
[CrossRef]

1989 (1)

1988 (1)

F. M. Davidson and X. Sun, "Gaussian approximation versus nearly exact performance analysis of optical communication systems with PPM signaling and APD receivers," IEEE Trans. Commun. 36(11), 1185‒1192 (1988).
[CrossRef]

Aitamer, N.

Andrews, L. C.

L. C. Andrews and R. L. Phillips, Laser Beam Propagation Through Random Media, 2nd. ed., SPIE Press, 2005.

Baars, J.

D. Rollins, J. Baars, D. Bajorins, C. Cornish, K. Fischer, and T. Wiltsey, "Background light environment for free-space optical terrestrial communications links," Proc. SPIE 4873, 99‒110 (2002).

Baedke, M.

S. G. Wilson, M. Brandt-Pearce, Q. L. Cao, and M. Baedke, "Optical repetition MIMO transmission with multipulse PPM," IEEE Sel. Areas Commun. 23(9), 1901‒1910 (2005).
[CrossRef]

Bajorins, D.

D. Rollins, J. Baars, D. Bajorins, C. Cornish, K. Fischer, and T. Wiltsey, "Background light environment for free-space optical terrestrial communications links," Proc. SPIE 4873, 99‒110 (2002).

Bourennane, S.

Brandt-Pearce, M.

S. G. Wilson, M. Brandt-Pearce, Q. L. Cao, and M. Baedke, "Optical repetition MIMO transmission with multipulse PPM," IEEE Sel. Areas Commun. 23(9), 1901‒1910 (2005).
[CrossRef]

Cao, Q. L.

S. G. Wilson, M. Brandt-Pearce, Q. L. Cao, and M. Baedke, "Optical repetition MIMO transmission with multipulse PPM," IEEE Sel. Areas Commun. 23(9), 1901‒1910 (2005).
[CrossRef]

Caussé, P.

Chazallet, F.

M. A. Khalighi, Y. Jaafar, F. Xu, F. Chazallet, and S. Bourennane, "Double-laser differential signaling for suppressing background radiations in FSO systems," Queen’s 25th Biennial Symp. on Communications (QSBC), 2010, Kingston, Canada, pp. 238‒241.

Cornish, C.

D. Rollins, J. Baars, D. Bajorins, C. Cornish, K. Fischer, and T. Wiltsey, "Background light environment for free-space optical terrestrial communications links," Proc. SPIE 4873, 99‒110 (2002).

Davidson, F. M.

F. M. Davidson and X. Sun, "Gaussian approximation versus nearly exact performance analysis of optical communication systems with PPM signaling and APD receivers," IEEE Trans. Commun. 36(11), 1185‒1192 (1988).
[CrossRef]

Davis, C. C.

C. C. Davis and I. I. Smolyaninov, "The effect of atmospheric turbulence on bit-error-rate in an on–off-keyed optical wireless system," Proc. SPIE 4489, 126‒137 (2002).

Fischer, K.

D. Rollins, J. Baars, D. Bajorins, C. Cornish, K. Fischer, and T. Wiltsey, "Background light environment for free-space optical terrestrial communications links," Proc. SPIE 4873, 99‒110 (2002).

Gagliardi, R. M.

R. M. Gagliardi and S. Karp, Optical Communications, 2nd. ed., Wiley, 1995.

Hagenauer, J.

J. Hagenauer, E. Offer, and L. Papke, "Iterative decoding of binary block and convolutional codes," IEEE Trans. Inform. Theory 42(2), 429‒445 (1996).
[CrossRef]

Jaafar, Y.

M. A. Khalighi, Y. Jaafar, F. Xu, F. Chazallet, and S. Bourennane, "Double-laser differential signaling for suppressing background radiations in FSO systems," Queen’s 25th Biennial Symp. on Communications (QSBC), 2010, Kingston, Canada, pp. 238‒241.

Karp, S.

R. M. Gagliardi and S. Karp, Optical Communications, 2nd. ed., Wiley, 1995.

Khalighi, M. A.

Leeb, W. R.

Offer, E.

J. Hagenauer, E. Offer, and L. Papke, "Iterative decoding of binary block and convolutional codes," IEEE Trans. Inform. Theory 42(2), 429‒445 (1996).
[CrossRef]

Papke, L.

J. Hagenauer, E. Offer, and L. Papke, "Iterative decoding of binary block and convolutional codes," IEEE Trans. Inform. Theory 42(2), 429‒445 (1996).
[CrossRef]

Phillips, R. L.

L. C. Andrews and R. L. Phillips, Laser Beam Propagation Through Random Media, 2nd. ed., SPIE Press, 2005.

Proakis, J. G.

J. G. Proakis, Digital Communications, 3rd. ed., McGraw-Hill, 1995.

Rollins, D.

D. Rollins, J. Baars, D. Bajorins, C. Cornish, K. Fischer, and T. Wiltsey, "Background light environment for free-space optical terrestrial communications links," Proc. SPIE 4873, 99‒110 (2002).

Saleh, B. E. A.

B. E. A. Saleh and M. C. Teich, Fundamentals of Photonics, Wiley, 1991.

Schwartz, N.

Sidorovich, V. G.

V. G. Sidorovich, "Solar background effects in wireless optical communications," Proc. SPIE 4873, 133‒142 (2002).

Smolyaninov, I. I.

C. C. Davis and I. I. Smolyaninov, "The effect of atmospheric turbulence on bit-error-rate in an on–off-keyed optical wireless system," Proc. SPIE 4489, 126‒137 (2002).

Sun, X.

F. M. Davidson and X. Sun, "Gaussian approximation versus nearly exact performance analysis of optical communication systems with PPM signaling and APD receivers," IEEE Trans. Commun. 36(11), 1185‒1192 (1988).
[CrossRef]

Teich, M. C.

B. E. A. Saleh and M. C. Teich, Fundamentals of Photonics, Wiley, 1991.

Wilson, S. G.

S. G. Wilson, M. Brandt-Pearce, Q. L. Cao, and M. Baedke, "Optical repetition MIMO transmission with multipulse PPM," IEEE Sel. Areas Commun. 23(9), 1901‒1910 (2005).
[CrossRef]

Wiltsey, T.

D. Rollins, J. Baars, D. Bajorins, C. Cornish, K. Fischer, and T. Wiltsey, "Background light environment for free-space optical terrestrial communications links," Proc. SPIE 4873, 99‒110 (2002).

Xu, F.

F. Xu, M. A. Khalighi, P. Caussé, and S. Bourennane, "Channel coding and time-diversity for optical wireless links," Opt. Express 17(2), 872‒887 (2009).
[CrossRef] [PubMed]

F. Xu, M. A. Khalighi, and S. Bourennane, "Coded PPM and multipulse PPM and iterative detection for free-space optical links," J. Opt. Commun. Netw. 1(5), 404‒415 (2009).
[CrossRef]

M. A. Khalighi, Y. Jaafar, F. Xu, F. Chazallet, and S. Bourennane, "Double-laser differential signaling for suppressing background radiations in FSO systems," Queen’s 25th Biennial Symp. on Communications (QSBC), 2010, Kingston, Canada, pp. 238‒241.

Appl. Opt. (1)

IEEE Sel. Areas Commun. (1)

S. G. Wilson, M. Brandt-Pearce, Q. L. Cao, and M. Baedke, "Optical repetition MIMO transmission with multipulse PPM," IEEE Sel. Areas Commun. 23(9), 1901‒1910 (2005).
[CrossRef]

IEEE Trans. Commun. (1)

F. M. Davidson and X. Sun, "Gaussian approximation versus nearly exact performance analysis of optical communication systems with PPM signaling and APD receivers," IEEE Trans. Commun. 36(11), 1185‒1192 (1988).
[CrossRef]

IEEE Trans. Inform. Theory (1)

J. Hagenauer, E. Offer, and L. Papke, "Iterative decoding of binary block and convolutional codes," IEEE Trans. Inform. Theory 42(2), 429‒445 (1996).
[CrossRef]

J. Opt. Commun. Netw. (2)

Opt. Express (1)

Proc. SPIE (3)

C. C. Davis and I. I. Smolyaninov, "The effect of atmospheric turbulence on bit-error-rate in an on–off-keyed optical wireless system," Proc. SPIE 4489, 126‒137 (2002).

D. Rollins, J. Baars, D. Bajorins, C. Cornish, K. Fischer, and T. Wiltsey, "Background light environment for free-space optical terrestrial communications links," Proc. SPIE 4873, 99‒110 (2002).

V. G. Sidorovich, "Solar background effects in wireless optical communications," Proc. SPIE 4873, 133‒142 (2002).

Other (5)

B. E. A. Saleh and M. C. Teich, Fundamentals of Photonics, Wiley, 1991.

L. C. Andrews and R. L. Phillips, Laser Beam Propagation Through Random Media, 2nd. ed., SPIE Press, 2005.

R. M. Gagliardi and S. Karp, Optical Communications, 2nd. ed., Wiley, 1995.

J. G. Proakis, Digital Communications, 3rd. ed., McGraw-Hill, 1995.

M. A. Khalighi, Y. Jaafar, F. Xu, F. Chazallet, and S. Bourennane, "Double-laser differential signaling for suppressing background radiations in FSO systems," Queen’s 25th Biennial Symp. on Communications (QSBC), 2010, Kingston, Canada, pp. 238‒241.

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 (6)

Fig. 1
Fig. 1

Block diagram of the receiver front end. PD, photodetector and bias circuit; TZ, transimpedance circuitry; LPF, low-pass filter; A/D, analog-to-digital converter.

Fig. 2
Fig. 2

Performance of D-OOK compared with the classical OOK for different ratios of background to thermal noise power k, no turbulence and no channel coding, and the BER curve for OOK with k = 0 the same as that of D-OOK.

Fig. 3
Fig. 3

Performance comparison of D-OOK and OOK for different k, no-turbulence (solid curves) and weak-turbulence (dashed curves) channels with σ R 2 = 0 . 04 . RSC ( 1 , 5 / 7 ) channel code, MAP signal detection, and SOVA decoding.

Fig. 4
Fig. 4

Performance of D-4PPM compared with the classical 4PPM and 8PPM, k = 0 , no turbulence, and no channel coding.

Fig. 5
Fig. 5

Performance of D-BPPM compared with the classical BPPM and 4PPM, k = 0 , no turbulence, and no channel coding.

Fig. 6
Fig. 6

Illustrative example for the power spectral density of the background noise. Hatched areas represent bandpass filtering of bandwidth B 0 around f 1 and f 2 , corresponding to the bandpass background noises’ field envelopes θ 1 and θ 2 .

Tables (3)

Tables Icon

Table I Bit-Symbol Mapping Example for the Classical 4PPM

Tables Icon

Table II Example of Optimized Bit-Symbol Mapping for D-4PPM

Tables Icon

Table III Bit-Symbol Mapping for the Differential BPPM Scheme With 2 Bits per Symbol

Equations (33)

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

r e = η I r + n ,
r 1 = h I 0 s 1 + n 1 λ 1 r 2 = h I 0 s 2 + n 2 λ 2 .
r d = h I 0 s d + n d .
r d h I 0 s d + n d , th .
P e = 1 2 erfc I 0 / ( σ d , th 2 ) = 1 2 erfc [ I 0 / ( 2 σ th ) ] ,
P e = 1 2 erfc I 0 / ( 2 σ n 2 ) = 1 2 erfc I 0 / ( 2 σ th 2 ( 1 + k ) ) .
I 0 = 2 P t ̄ ; E b = 2 P t ̄ 2 R b ; σ n 2 = P t ̄ 2 E b / N 0 ( 1 + k ) .
I 0 = P t ̄ ; E b = P t ̄ 2 R b ; σ n 2 = P t ̄ 2 E b / N 0 .
Δ E b / N 0 = ( E b / N 0 ) D - OOK ( E b / N 0 ) OOK (in dB) .
Δ P t ̄ = 1 . 5 + 1 2 Δ E b / N 0 (in dB).
b ˆ = arg max b P ( r d b ) P ( b ) .
b ˆ = arg max b P ( r d b ) .
LLR ( b 1 ) = log Prob { r d b 1 = 1 } Prob { r d b 1 = 0 } ,
Prob { r d b 1 = 1 } = Prob { x d = ( 1 , 0 , 1 , 0 ) } + Prob { x d = ( 0 , 1 , 0 , 1 ) } + Prob { x d = ( 0 , 0 , 1 , 1 ) } + Prob { x d = ( 1 , 1 , 0 , 0 ) } ,
Prob { x d = ( 1 , 0 , 1 , 0 ) } = p 1 ( r d 1 ) p 0 ( r d 2 ) p 1 ( r d 3 ) p 0 ( r d 4 ) .
p 1 ( r d 1 ) = 1 2 π σ d , th exp ( r d 1 h I 0 ) 2 2 σ d , th 2 .
L 1 = h I 0 σ th 2 [ max ( r d 2 r d 1 , r d 4 r d 3 , r d 1 r d 3 , r d 2 r d 4 ) max ( r d 1 r d 2 , r d 3 r d 4 , r d 3 r d 1 , r d 4 r d 2 ) ] .
I 0 = 4 P t ̄ ; E b = 4 P t ̄ 2 R b ; σ n 2 = 4 P t ̄ 2 E b / N 0 ( 1 + k ) .
I 0 = 8 P t ̄ ; E b = 8 P t ̄ 2 R b ; σ n 2 = 32 P t ̄ 2 3 E b / N 0 ( 1 + k ) .
I 0 = 2 P t ̄ ; E b = 2 P t ̄ 2 R b ; σ n 2 = 2 σ th 2 = 8 P t ̄ 2 3 E b / N 0
L 1 = h I 0 σ th 2 [ max ( x d 1 , x d 2 ) max ( x d 1 , x d 2 ) ] , L 2 = h I 0 σ th 2 [ max ( x d 1 , x d 2 ) max ( x d 1 , x d 2 ) ] .
I 0 = 2 P t ̄ ; E b = 2 P t ̄ 2 R b ; σ n 2 = 2 P t ̄ 2 E b / N 0 ( 1 + k ) .
I 0 = 2 P t ̄ ; E b = 2 P t ̄ 2 R b ; σ n 2 = 2 σ th 2 = 2 P t ̄ 2 E b / N 0 .
Δ P t ̄ = 1 2 Δ E b / N 0 (in dB) .
I θ 1 = T s θ 1 ( t ) 2 d t ,
θ 1 ( t ) = + h 1 ( τ ) θ ( t τ ) d τ .
θ 1 ( t ) 2 = + + h 1 ( τ 1 ) θ ( t τ 1 ) h 1 ( τ 2 ) θ ( t τ 2 ) d τ 2 d τ 1 .
I θ 1 = + + h 1 ( τ 1 ) h 1 ( τ 2 ) T s θ ( t τ 1 ) θ ( t τ 2 ) d t d τ 2 d τ 1 .
T s θ ( t τ 1 ) θ ( t τ 2 ) d t = E { θ ( t τ 1 ) θ ( t τ 2 ) } ,
E { θ ( t τ 1 ) θ ( t τ 2 ) } σ θ 2 δ ( τ 1 τ 2 ) ,
I θ 1 = σ θ 2 + h 1 (τ) 2 d τ .
I θ 1 I θ 2 = σ θ 2 + [ h 1 (τ) 2 h 2 (τ) 2 ] d τ .
n d , bk = σ θ 2 + [ H 1 ( f ) 2 H 2 ( f ) 2 ] d f = 0 .