07609972 is referenced by 12 patents and cites 9 patents.

A technique for acquiring and tracking terminals in a free-space laser communication system involves exchanging beacon laser beams between the terminals to acquire and then track the terminals such that data laser beams exchanged by the terminals for communication are steered based on feedback from detection of the beacon laser beams. The beacon laser beams used for acquisition have a greater beam divergence than those used for tracking. Gimbals provide coarse steering of the data laser beams, and steering mirrors provide fine steering. GPS position data exchanged via an RF link can be used for initial pointing of the beacon laser beams for acquisition. The beacon laser beams can be chopped such that all terminals can use the same beacon wavelength and are distinguished by using different chopping frequencies. By detecting a chopped signal, the position sensor detector can be AC coupled to reduce sensitivity to solar radiation and glint.

Title
Acquisition, pointing, and tracking architecture for laser communication
Application Number
11/194741
Publication Number
7609972 (B2)
Application Date
August 2, 2005
Publication Date
October 27, 2009
Inventor
Donald Fisher
Spring Valley Township
OH, US
Dean Grinch
Dublin
OH, US
James Cunningham
Dayton
OH, US
Agent
Edell Shapiro & Finnan
Assignee
ITT Manufacturing Enterprises
DE, US
IPC
H04B 10/00
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