Method and apparatus for controlling received power levels within a free space optical communication system
AssigneeLucent Technologies Inc.
InventorsHerman Melvin Presby, John A. Tyson
Life of this patent
Estimating the term…
Abstract
A free space optical communication system is disclosed whereby the received power at the receive optical fiber is reduced by adjusting the transmitted light beam and/or the receive optical fiber with respect to each other when a specified power threshold is exceeded. This reduction in received power is achieved by either increasing the cross section of the transmitted beam relative to the receive telescope or, alternatively, moving the receive optical fiber and thereby enlarge the cross section of the received beam incident upon the receive optical fiber.
Claims26
A transmit telescope comprising:
- means for transmitting a light beam to a receive telescope;
- and
- means operative, in response to a signal indicative of an excessive received signal power condition at the receive telescope, for adjusting the transmitted light beam so that it diverges as the light beam is transmitted by said transmitting means, thereby increasing the cross-sectional area of the transmitted beam incident upon the receive telescope.
A receive telescope comprising:
- means for receiving a light beam transmitted by a transmit telescope;
- and means for generating a signal indicative of an excessive received power condition that is operative for adjusting the transmitted light beam so that it diverges as the light beam is transmitted by said transmit telescope, thereby increasing the cross-sectional area of the transmitted beam incident upon the receive telescope.
A receive telescope comprising:
- means for receiving a light beam from a transmit telescope;
- and
- means for moving a receive optical fiber to a point away from the focal plane of the receive telescope along the longitudinal axis of an optical system of the receive telescope, thereby increasing the cross-sectional area of the received light beam incident upon the receive optical fiber.
A method in a free-space optical communication system comprising:
- increasing, in response to a signal indicative of an excessive received power condition, the cross-sectional area of a transmitted light beam incident upon a receive telescope by adjusting said beam so that it diverges as the light beam is transmitted by the transmit telescope.
A method in a free space optical communication system comprising:
- moving a receive optical fiber, located at or near the focal plane of an optical system of the receive telescope, along the longitudinal axis to a point away from a focal plane of an optical system of the receive telescope, thereby increasing the cross-sectional area of a received light beam incident upon the receive optical fiber.
A free space optical communication system comprising:
- a transmit telescope for transmitting a light beam;
- a receive telescope for receiving the transmitted light beam;
- and
- means operative, in response to a signal indicative of an excessive received power condition at the receive telescope, for adjusting the transmitted light beam so that it diverges as the light beam is transmitted by said transmit telescope transmitting means, thereby increasing the cross-sectional area of the transmitted beam incident upon the receive telescope.
A free space optical communication system comprising:
- a transmit telescope for transmitting a light beam;
- a receive receive optical fiber located at or near the focal plane of an optical system of a receive telescope;
- and
- means operative, in response to a signal indicative of an excessive received power condition at the receive telescope, for adjusting the transmitted light beam so that it diverges as the light beam is transmitted by said transmit telescope, thereby increasing the cross-sectional area of the transmitted beam incident upon the receive telescope.
Dependencies are inferred from the claim text.