A point-to-multipoint bi-directional wide area telecommunications network employing atmospheric optical communication. The network comprises a primary transceiver unit, a plurality of subscriber transceiver units and an optical router. The primary transceiver unit generates a first light beam on which it modulates first data. The primary transceiver unit atmospherically transmits the first light beam to the optical router which demodulates the first data, modulates the first data on a second light beam and transmits the second light beam to the plurality of subscriber transceiver units in multiplexed manner. The subscriber transceiver units receive the second light beam and demodulate the first data from the second light beam. Conversely, the subscriber transceiver units atmospherically transmit a third light beam on which they modulate second data to the optical router which demodulates the second data, modulates the second data on a fourth light beam and transmits the fourth light beam to the primary transceiver unit. The primary transceiver unit atmospherically receives the fourth light beam and demodulates the respective second data from the fourth light beam. The optical router of the network comprises a secondary transceiver unit, a plurality of transceiver modules and an electronic router for routing data between the secondary transceiver unit and the plurality of transceiver modules to establish communication channels between the primary transceiver unit and the plurality of subscriber transceiver units. The secondary transceiver unit communicates with the primary transceiver unit and the transceiver modules communicate with the subscriber transceiver units. The transceiver modules comprise an X-Y beam deflector for deflecting the second and third light beams to a portion of the subscriber transceiver units in a time-multiplexed fashion. In an alternate embodiment of the optical router, the first light beam is redirected to the subscriber transceiver units and the third light beam is redirected to the primary transceiver unit by a mirror and lens set assembly rather than being demodulated and modulated in the router. Applications such as telephony, the Internet, teleconferencing, radio broadcast, HDTV, interactive TV, and other television forms are contemplated for employment on the network.

Point-to-multipoint wide area telecommunications network via atmospheric laser transmission through a remote optical router

A hybrid cable (100) comprising an optical fiber (110), an intermediate layer (120) surrounding the optical fiber, and an electrically insulating jacket (130) surrounding the intermediate layer. The intermediate layers include a collection of metallic strands. The hybrid cable may be used to establish simultaneous electrical and fiber-optic connection between two communication devices. Thus, the two communication devices may simultaneously transfer optical signals through the optical fiber and perform any of various electrical functions (power transfer, eye safety control) through the metallic strands. For example, an optical transceiver may couple to an optical antenna unit through the hybrid cable. Such an optical transceiver may serve as part of a point-to-point link, a point-to-multipoint link, and/or, a link between a primary transceiver unit and an optical router.

Hybrid electro-optic cable for free space laser antennas

A free-space optical data transmission system, comprised of first and second transceivers (10, 10') spaced a distance from each other and having telescopes (14,14') aimed at each other. Each transceiver (10, 10') has a transmitter (T, T') for transmitting data-encoded light from its telescope (14) to the other telescope (14'), and a receiver (R, R') for receiving light from the other telescope. Each transceiver (10, 10') has a wavefront sensor (WFS, WFS') for determining the curvature of the wavefront of light transmitted between the telescopes, which may be distorted by atmospheric aberrations; and a deformable curvature mirror (DM, DM') connected to the wavefront sensor (WFS,WFS') and in the path of the data-encoded light for modifying the wavefront curvature of the light in response to the wavefront sensor (WFS, WFS'). Preferably, each transceiver (10, 10') has an arrangement for separating the transmitted and received light waves for bidirectional transmission.

Atmospheric optical data transmission system

A balloon may include an optical-communication component, which may have a pointing axis. A pointing mechanism could be configured to adjust the pointing axis. The optical-communication component could be operable to communicate with a correspondent balloon via a free-space optical link. For example, the optical-communication component could include an optical receiver, transmitter, or transceiver. A controller could be configured to determine a predicted relative location of the correspondent balloon. The controller may control the pointing mechanism to adjust the pointing axis of the optical-communication component based on the predicted relative location so as to maintain the free-space optical link with the correspondent balloon.

Using predicted movement to maintain optical-communication lock with nearby balloon

A point-to-multipoint bi-directional wide area telecommunications network employing atmospheric optical communication. The network comprises a primary transceiver unit, a plurality of subscriber transceiver units and an optical router. The primary transceiver unit may send data destined for the subscriber transceiver units through the optical router, and the subscriber transceiver units may send data destined for the primary transceiver unit through the optical router. The primary transceiver unit and optical router communicate by means of light beams which are transmitted through the atmosphere. Similarly, the optical router and the subscriber transceiver units communicate by means of light beams which are transmitted through the atmosphere.

Laser based telecommunication network and router

An optical communications system is disclosed for correcting in real-time the wavefront distortions of a beam from a coherent optical transmitting source The system includes a collimating lens and beam splitter for receiving a distorted wavefront signal beam and splitting the beam into a pump beam and a weaker intensity signal beam The system includes a detector and computer for measuring the beam distortion and specifying a compensatory wavefront The weaker intensity signal beam is modified in a 2-D spatial light modulator according to a compensatory wavefront A photo-refractive material is used to couple energy from the pump beam to the compensated wavefront signal beam thereby producing a corrected and intensity-enhanced communications beam

Frederic M. Davidson

Papers

Efficient dynamic phasefront modulation system for free-space optical communications