Wide-angle, high-speed, free-space optical communications system

A free-space optical communications system for transmitting data bidirectionally between an aircraft computer system and a ground-based computer system, comprising:

• a first optical transmitter coupled to the aircraft computer system and a second optical transmitter coupled to the ground-based computer system, each transmitter including:
• (a) a light source that produces optical signals corresponding to the data to be transmitted between the aircraft computer system and the ground-based computer system;
• (b) means for collecting the optical signals produced by the light source and distributing the optical signals uniformly over a target area;
• and
• a first optical receiver coupled to the ground-based computer system and a second optical receiver coupled to the aircraft computer system that receive the optical signals transmitted from a corresponding optical transmitter, wherein each optical receiver includes:
• (a) a photodiode that produces an output signal that is proportional to a received optical signal;
• (b) a compound parabolic concentrator bonded to the photodiode that collects the optical signals transmitted from the optical transmitter and directs the optical signals onto the photodiode;
• (c) current shunt means coupled to an output of the photodiode for shunting away a portion of the output signal that is due to ambient light collected by the compound parabolic concentrator.

A free-space optical communications system for transmitting data bidirectionally between an aircraft computer system and a ground-based computer system, comprising:

• a pair of optical transmitters, one of which is coupled to the aircraft computer system and another of which is coupled to the ground-based computer system, wherein each of the optical transmitters includes:
• (a) one or more light-emitting diodes (LEDs) that produce optical signals that correspond to data to be transmitted;
• (b) a hollow horn having a reflective interior surface that surrounds the one or more LEDs for uniformly distributing optical signals produced by the LEDs over a target area, and
• a pair of optical receivers, one of which is coupled to the aircraft computer system and another of which is coupled to the ground-based computer system, wherein each optical receiver includes:
• (a) means for gathering light that impinges upon the optical receiver;
• (b) a photodiode bonded to the means for gathering light, the photodiode producing an electrical signal that is proportional to the amount of light gathered;
• and
• (c) filter means disposed in front of the means for gathering light for reducing the amount of ambient light received by the photodiode.

A method of optically transmitting data between an aircraft computer system and a ground-based computer system, comprising the steps of:

• producing an infrared optical signal that corresponds to the data to be transmitted;
• directing the infrared optical signal through light distributing means so that the optical signal is evenly distributed within a target area in which an optical receiver is positioned;
• gathering light at the optical receiver using a compound parabolic concentrator that is bonded to a photodiode, the photodiode producing an electrical signal proportional to the amount of light gathered;
• removing a component of the electrical signal produced by the photodiode due to ambient light gathered by the compound parabolic concentrator;
• and
• coupling an AC component of the electrical signal produced by the photodiode to an amplifier, wherein a magnitude of the AC component of the electrical signal is proportional to the data transmitted between the aircraft computer system and the ground-based computer system.

An optical transceiver adapted to be coupled to an exterior of an aircraft for transmitting and receiving data between an aircraft computer system and a ground-based computer system comprising:

• an optical transmitter for producing optical signals that correspond to data to be transmitted from the aircraft computer system to the ground-based computer system, including:
• (a) one or more light sources coupled to the aircraft computer system for producing the optical signals corresponding to data that is transmitted from the aircraft computer system to the ground-based computer system;
• (b) light distributing means for gathering the optical signals and distributing the optical signals uniformly over a target area;
• an optical receiver for receiving optical signals that are transmitted from a second optical transmitter coupled to the ground-based computer system, including:
• (a) a photodiode that produces an output signal that is proportional to a received optical signal;
• (b) a compound parabolic concentrator bonded to the photodiode that collects optical signals and directs the collected optical signals onto the photodiode;
• and
• (c) a current shunt coupled to the output signal produced by the photodiode that shunts a portion of the output signal due to ambient light collected by the light-collecting means.

An optical communications system for transmitting data bidirectionally between a first computer system and a second computer system, comprising:

• an optical transmitter coupled to the first computer system for producing optical signals that correspond to the data to be transmitted between the first computer system and the second computer system, wherein the optical transmitter includes:
• (a) light-producing means for producing optical signals corresponding to the data to be transmitted;
• (b) light distributing means for gathering the optical signals produced by the light-producing means and for distributing the optical signals uniformly over a target area;
• an optical receiver coupled to the second computer system for receiving the optical signals produced by the optical transmitter, wherein the optical receiver includes:
• (a) a photodiode for producing an output signal that is proportional to a received optical signal, the output signal of the photodiode being coupled to the second computer system for producing an output signal that corresponds to the data transmitted;
• (b) a compound parabolic concentrator bonded to the photodiode for gathering a portion of the optical signals produced by the light-producing means and for directing the portion of the optical signals gathered to the photodiode;
• and
• (c) light-filtering means disposed in front of the compound parabolic concentrator for reducing the amount of ambient light received by the photodiode.