### Abstract

We study the scintillation index of N partially overlapping lowest order Gaussian laser beams with different wavelengths in weak atmospheric turbulence. Assuming a Von Karman turbulence spectrum and slow detector response and using the Rytov approximation we calculate the longitudinal and radial components of the scintillation index for typical free-space laser communication setups. We find the initial beam separation that minimizes the longitudinal scintillation and corresponds to the optimal beam configuration. Further reduction of the longitudinal scintillation is obtained by optimizing with respect to both initial beam separation and initial spot size. The longitudinal scintillation of the optimal N-beam configurations is inversely proportional to N, resulting in a 92% reduction for a 9-beam system compared with the single beam value. The existence of the minimum of longitudinal scintillation is not very sensitive to the form of the turbulence spectrum. Moreover, the radial scintillation values for the optimal N-beam configurations are found to be significantly smaller than the corresponding single beam values, and this reduction effect also grows with increasing N.

Original language | English (US) |
---|---|

Title of host publication | Proceedings of SPIE - The International Society for Optical Engineering |

Volume | 6457 |

DOIs | |

State | Published - 2007 |

Event | Free-Space Laser Communication Technologies XIX and Atmospheric Propagation of Electromagnetic Waves - San Jose, CA, United States Duration: Jan 24 2007 → Jan 25 2007 |

### Other

Other | Free-Space Laser Communication Technologies XIX and Atmospheric Propagation of Electromagnetic Waves |
---|---|

Country | United States |

City | San Jose, CA |

Period | 1/24/07 → 1/25/07 |

### Fingerprint

### ASJC Scopus subject areas

- Electrical and Electronic Engineering
- Condensed Matter Physics

### Cite this

*Proceedings of SPIE - The International Society for Optical Engineering*(Vol. 6457). [64570M] https://doi.org/10.1117/12.711187

**Scintillation index for N Gaussian laser beams with different wavelengths in weak atmospheric turbulence.** / Peleg, A.; Moloney, Jerome V.

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

*Proceedings of SPIE - The International Society for Optical Engineering.*vol. 6457, 64570M, Free-Space Laser Communication Technologies XIX and Atmospheric Propagation of Electromagnetic Waves, San Jose, CA, United States, 1/24/07. https://doi.org/10.1117/12.711187

}

TY - GEN

T1 - Scintillation index for N Gaussian laser beams with different wavelengths in weak atmospheric turbulence

AU - Peleg, A.

AU - Moloney, Jerome V

PY - 2007

Y1 - 2007

N2 - We study the scintillation index of N partially overlapping lowest order Gaussian laser beams with different wavelengths in weak atmospheric turbulence. Assuming a Von Karman turbulence spectrum and slow detector response and using the Rytov approximation we calculate the longitudinal and radial components of the scintillation index for typical free-space laser communication setups. We find the initial beam separation that minimizes the longitudinal scintillation and corresponds to the optimal beam configuration. Further reduction of the longitudinal scintillation is obtained by optimizing with respect to both initial beam separation and initial spot size. The longitudinal scintillation of the optimal N-beam configurations is inversely proportional to N, resulting in a 92% reduction for a 9-beam system compared with the single beam value. The existence of the minimum of longitudinal scintillation is not very sensitive to the form of the turbulence spectrum. Moreover, the radial scintillation values for the optimal N-beam configurations are found to be significantly smaller than the corresponding single beam values, and this reduction effect also grows with increasing N.

AB - We study the scintillation index of N partially overlapping lowest order Gaussian laser beams with different wavelengths in weak atmospheric turbulence. Assuming a Von Karman turbulence spectrum and slow detector response and using the Rytov approximation we calculate the longitudinal and radial components of the scintillation index for typical free-space laser communication setups. We find the initial beam separation that minimizes the longitudinal scintillation and corresponds to the optimal beam configuration. Further reduction of the longitudinal scintillation is obtained by optimizing with respect to both initial beam separation and initial spot size. The longitudinal scintillation of the optimal N-beam configurations is inversely proportional to N, resulting in a 92% reduction for a 9-beam system compared with the single beam value. The existence of the minimum of longitudinal scintillation is not very sensitive to the form of the turbulence spectrum. Moreover, the radial scintillation values for the optimal N-beam configurations are found to be significantly smaller than the corresponding single beam values, and this reduction effect also grows with increasing N.

UR - http://www.scopus.com/inward/record.url?scp=34247373809&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34247373809&partnerID=8YFLogxK

U2 - 10.1117/12.711187

DO - 10.1117/12.711187

M3 - Conference contribution

AN - SCOPUS:34247373809

SN - 0819465739

SN - 9780819465733

VL - 6457

BT - Proceedings of SPIE - The International Society for Optical Engineering

ER -