Abstract: A portable transceiver of one or more signals includes an input, frequency modulation, a splitter and a plurality of lasers in a transmitter module. A receiver module includes a Mangin mirror aligned with an input aperture. A photodiode receives the signal from the mirror for subsequent demodulation. An interference filter is arranged between the mirror and the photodiode. The filter is hemispherical, having a center of curvature at the focal point of the mirror. The transceiver may include a video camera and gyro-stabilizer accessories. A visual siting scope is aligned with the lasers and the receiver. A separate transceiver for ethernet input signals interfaces with a 10/100 ethernet switch and does not employ frequency modulation.

Abstract: A method and system for dispersion control of electromagnetic signals in communication networks by narrowing the widths of electromagnetic pulses such as modulated laser signals. Generally, in the preferred embodiment, the present invention utilizes a feedback loop based on dither frequency modulation which dynamically adjusts the alignment of the laser center frequency with the filter passband. In this way, there is an acceptable tradeoff between optical power and pulse width, so a higher power laser can be used to generate a narrower optical pulse. The narrower pulses then travel farther in the fiber link before reaching their dispersion limit. It is believed that, by using this invention, existing link distance could be doubled, while re-using existing installed singlemode fiber. The systems employing the feedback loop may be information carrying or control systems.

Abstract: An addressable system for light fixtures is described wherein a plurality of light fixture modules is individually or collectively addressable for programming by remote control. The remote control may individually select each of the track control modules through visible and narrowly defined selected light followed by transmission of programming commands for programming of pre-defined scenes, functions or other user defined and desired effects. Each of the track fixture modules may be selected or de-selected through the use of laser light and a plurality of track control modules may be collectively programmed through the use of a track repeater module, all of the modules communicatively connected to each other and selectable by a visible narrow light source such that the user may readily activate or de-activate programming sequences.

Abstract: A large fiber optic switch system with a free-space optical interconnection configuration. The switch system comprises a plurality of individual switch units, each individual switch unit having a plurality of electronic multi-switch switches each multi-switch switch being re-configurable upon command of a computer processor and having a plurality of electronic input ports and electronics output ports. A first portion of these input ports and a first portion of these output ports are connected directly or indirectly to incoming and outgoing communication lines. A second portion of the output ports is connected to an electronic driver unit that drives an optical emitter array. Each emitter in the emitter array produces a light beam for carrying an optical communication signal.

Abstract: An addressable light fixture is described wherein a light fixture module is individually addressable for programming by remote control. The remote control may individually select each light fixture module through visible and narrowly defined selected light followed by transmission of programming commands for programming of pre-defined scenes, functions or other user defined and desired effects. Each of the fixture modules may be selected or de-selected through the use of laser light and a plurality of track control modules may be collectively programmed through the use of a repeater module, all of the modules communicatively connected to each other and selectable by a visible narrow light source such that the user may readily activate or de-activate programming sequences.

Abstract: The present invention discloses an integrated circuit receiver available for infrared or ultrasonic transmission by use of digital filtering for demodulation of infrared or ultrasonic carrier signal. The integrated circuit receiver comprises an infrared receiver or ultrasonic transducer to receive the transmitted signal from outside and output a modulated carrier signal. The modulated carrier signal is fed to an amplifier circuit to be amplified and then outputted to a digital filter to filter out the carrier from the amplified signal, and thus a digital data signal is recovered. The filtering thereof is done by a digital filter instead of an analog one.

Abstract: A communication system includes a plurality of nodes and a plurality of point-to-point links that interconnect the plurality of nodes into a network. Each node includes an optical switch to controllably route a plurality of in-ports of the optical switch into a plurality of out-ports of the optical switch. Each point-to-point link includes a free space optical channel. A first free space optical channel couples to a first node through a receive path and through a transmit path. The receive path couples to a respective in-port of the optical switch of the first node, and the transmit path couples to a respective out-port of the optical switch of the first node. In an alternative embodiment, a communication hub includes a plurality of neighborhood links to corresponding users, an optical switch coupled to the plurality of neighborhood links, and a trunk coupled between the optical switch and a free space optical channel link to the network.

Abstract: Internal communication signals in a stored program controlled system comprising a plurality of units configured to process signals are provided by a free space optical beam line which is proximal to all of the plurality of units. The free space beam line is configured to contain optically encoded signals which comprises signals transmitted between and/or among the plurality of units. Each unit includes a probe for injecting optically encoded signals in the free space beam line and/or and for receiving optically encoded signals from the free space beam line. Advantageously, there may be a first terminal at a first end of the beam line to configure to transmit and terminate the optically encoded signals and a second terminal unit at the second end of the free space beam line configured to transmit and terminate the optically encoded signals.

Abstract: In an array-antenna base-station apparatus 100, a relay-station apparatus 110 and a control-station apparatus 120 are connected with optical cables 140, 150, and, moreover, calibration of the whole apparatus 100 is performed to improve the performances of the above whole apparatus 100.

Abstract: For a WDM optical communication, on a substrate of an arrayed waveguide type wavelength multiplexing/demultiplexing device, input waveguide propagates a plurality of light and outputs WDM light; a first slab diffuses the WDM light outputted from the input waveguide; a channel waveguide array separates the WDM light and causes the separated six lights to propagate; a second slab condenses the separated six lights having propagated through the channel waveguide array; output waveguides causes the separated six lights condensed to propagate, and a waveguide interval in first neighborhoods connected to the first slab is set to become wider than a first waveguide interval in a first connection section for connecting the channel waveguide array to the first slab, which achieves a reduced chip size, cost-reduction of chips, and reduces loss.

Abstract: The present invention provides a method and network for communicating over free space links. The network includes a plurality of buildings, each housing at least one of a residence and a business. Pluralities of free-space optical links are established, where each optical link is defined between two of the buildings, and data is communicated across the plurality of links. Each of the buildings includes a distribution system configured to receive the data communicated across at least one of the links and to distribute the data to an intended recipient. The plurality of optical links are configured to form a network topology providing alternate communication paths for at least two of the plurality of buildings and an external network is coupled with the optical communication network, wherein at least some of the data is communicated between the external network and the optical communication network.

Abstract: Apparatus and methods for implementing a high-power or high-sensitivity tracking mode of operation in a free-space optical communication system are disclosed. Functions of the high-power or high-sensitivity tracking mode may be implemented in response to one or more engage signals generated and transmitted in response to a sensed inclement weather condition, such as fog or the like, which may interfere with communication of an optical signal between a pair of free-space optical terminals in the free-space optical communication system. Implementation of the high-power or high-sensitivity tracking mode facilitates maintenance of the alignment between the pair of free-space optical terminals throughout the duration of the inclement weather condition to allow data communication to resume fully after the inclement weather condition has diminished.

Abstract: An optical inter-satellite link (OISL) gimbal 10 that is particularly suited for directing an optical beam in an optical inter-satellite communications system is disclosed. The OISL gimbal 10 includes an azimuth drive housing 20, a generally cylindrical azimuth shaft 22 rotatably connected to the azimuth drive housing 20 and an optical payload 210 or beam-steering mirror 70 rotatably connected to the azimuth shaft 22. The azimuth shaft 22 has a clear aperture through which one or more optical beams may be directed to and from a stationary optical payload 30. A capacitive azimuth position sensor 40 detects the rotational position of the azimuth shaft 22 and a direct drive azimuth motor 50 drives rotation of the azimuth shaft 22. The OISL gimbal 10 preferably provides two-axis rotation of the optical payload 210 or beam-steering mirror 70 through approximately +/?180 degrees of inboard (azimuth) travel and +/?30 degrees of line-of-sight outboard (elevation) travel.

Abstract: An Infrared Data Association (IrDA) communication range (109) (e.g., 1 meter) of an IrDA compliant portable device (201) is increased to an extended range infrared communication (ERIC) range (209) (e.g., 2 to 40 meters) by extending a transmission range over an uplink channel (207) from the portable device (201) up to a base station (202) and by extending a transmission range over the downlink channel (208) from the base station (202) down to the portable device (201).

Abstract: Building-to-building over the air transmission of optical data is a growing area of data communications. The fast growing use of bandwidth mandates the use of over the air transmission equipment capable of similar performance as the performance of fiber optic transmission, for distances of 3-10 Km. Transparent transmission is important to enable seamless growth from low data-rare to Gbps rates, and then to Dense Wavelength Division Multiplexed (DWDM) transmission of several wavelengths. The only way to achieve the required performance is with narrow, directable beams. This patent application discloses a Micro-Electro-Mechanical-Systems (MEMS) mirror based, over the air, optical data transmission system. A narrow optical beam is used and a MEMS mirror fine-tunes the aiming of the beam to track building movement, vibrations etc.

Abstract: Systems and methods for the transmission of auxiliary data via a modulated carrier signal superimposed on a primary data communication signal between terminals of a free-space optical communication system are disclosed. The carrier signal is modulated with an auxiliary data signal via phase-shift keying, amplitude-shift keying, frequency-shift keying, or other suitable modulation technique, and superimposed on the primary data communication signal prior to transmission as an optical signal by a transmitting free-space optical terminal. The primary data communication signal is received by at least one photo detector coupled to a receiving free-space optical terminal that demodulates the primary data communication signal to reconstruct the auxiliary data.

Abstract: Erbium doped fiber amplifiers (ERDAs) optically couple optical signals between free-space and fiber optic links of a terrestrial optical communication network. The optical gain of transmitting and receiving ERDAs is controlled to achieve good optical signal communication. Control occurs in response to signals received at the transmitting and receiving ends of the links. Control, status and management information may be communicated optically between link head stations. The physical position of transceivers at opposite ends of the link optical signal paths is also controlled.

Abstract: A window-mounted positionable collector comprising a base that is secured to a window. An inner rotatable hollow wedge-cut member may be rotated about the base to produce a first degree of freedom, while an outer rotatable hollow wedge-cut member may be rotated about a top end of the inner rotatable hollow wedge-cut member to provide a second degree a freedom. The combination of the first and second degrees of freedom enables the optical axis of an optical collector operatively coupled to the outer rotatable hollow wedge-cut member to be directed along any direction falling within a cone of angulation defined by acute angles corresponding to the angles of the wedge cuts defined in the rotatable hollow wedge cut members. In one embodiment, a cover is connected to a top end of the outer rotatable hollow wedge-cut member to form a sealed volume, whereby the apparatus may be secured to the window by applying a vacuum to the sealed volume.

Abstract: This invention extends the range of optical data of mobile device by trading speed for distance as well as integrating a plurality of pulses over time to define a single bit of information. The present invention uses a number of integrated pulses to represent a single bit instead of utilizing a one to one correspondence between pulses and bits. The present invention executes a range extender application which executes on the mobile device without any hardware modification to the mobile device. The range extender application causes the optical transmitter to “stutter” or repetitively emanate the identical pulse representing a bit of information. Sufficient photons are thereby gathered at a receiver to reach a predetermined threshold. A tradeoff of the data transmission frequency in this invention is that a signal intensity drops by a factor of 100 when distance increases by a factor of 10 yielding a distance/intensity ratio of {fraction (1/10)}.

Abstract: A free space point-to-multipoint optical transceiver has a reflective element and an optical feed mounted on the reflective element. When the optical feed is coupled to a light source, the optical feed is positionable to direct light received from the light source onto a reflective surface of the reflective element. Light directed onto the reflective surface is reflected towards a remote location to be received by a receiver located at the remote location. By adjusting a position of the optical feed, the reflected light is aimed. Therefore, adjusting the position of the optical feed provides a technique to track moving remote locations and/or to target different remote locations.

Abstract: A remote control and flashlight has a housing with top and bottom portions. A periphery between the portions has at least one aperture there through. The top portion also has an upper face with a plurality of holes. The bottom portion has a bottom face with a window and a latchable covering. An infrared light emitting diode transmits a narrow beam of modulated infrared light having a central axis of dissemination. A lightbulb for emits visible light with a central axis of dissemination. A power source is electrically coupled to the infrared light emitting diode and lightbulb. A plurality of function buttons pass through holes in the housing with control circuitry being adapted to activate and modulate the infrared light source. An on/off button passes through a hole in the housing to activate and inactivate the lightbulb.

Abstract: An optical wireless communications system (1) comprises a server or transceiver hub (6) transmitting and/or receiving optical communications with geographically dispersed subscriber units (8) via optical beams. The transceiver hub (6) transmits a beam pattern that has an efficient, rectangular, flat-topped far field optical profile, thus permitting less complex and less expensive transceiver equipment to be employed in the transceiver hub (6) and in the subscriber units (8). In one embodiment, the transceiver hub (6) comprises an optical source (52, FIG. 3), an asymmetrical lens such as a cylindrical lens (60, FIG. 3), and a diffraction element such as a diffractive phase plate (65, FIG. 3). Various methods of shaping an optical transmission profile are also described.

Abstract: A wireless atmospheric site-to-site full-duplex (i.e., simultaneous transmit and receive) laser communication system, typically for wideband (high-speed) data, voice, and/or video transmission. The system includes at least one laser communication transceiver each having an electro-optical transmitter that includes a laser source for generating laser light to be transmitted site-to-site and at high speed, an electro-optical receiver that includes a baffle assembly for receiving light directly onto a detector, without an intermediate field stop and re-imaging relay optics to reject off-axis light sources. Wideband data are transmitted and received through the atmosphere by the electro-optical transmitter and the electro-optical receiver. The data to be transmitted through each laser communication transceiver is inputted through a fiber-optic receiver and outputted by a fiber-optic transmitter.

Abstract: A method of managing a free-space optical network includes monitoring environmental and weather conditions in the vicinity of one or more free-space optical links in the network. Data is gathered by environmental condition instruments, such as visibility meters, and is used to assess whether atmospheric conditions have deteriorated to the point where operation of one or more free-space links might be in jeopardy. If data from an environmental condition instrument falls below a predetermined level, network data traffic is routed over an alternate communication path, which may include radio frequency (RF) paths, fiber optic cables, wire cables, or other free-space links.

Abstract: An optical transmission device configured as a central node, wherein each central node has dedicated pixels for receiving data and transmitting optical data so destination addressing is not required. The network is configured such that transmission on any particular receiver reserved pixels results in data being sent to a predetermined node. In particular, the star topology is configured as a receiver reserved scheme. The device is formed by constructing central node of transmitters and receivers that are attached to a silicon substrate with a processing means, and the optical interface to the transmitters and detectors on the central node establish a one-to-one correspondence with an individual fiber optic cable. The fiber optic cables are reconfigurable to different topologies or interconnections as each fiber optic cable has a known destination on the central node. Various topologies are possible using a star node as the building block.

Abstract: A light emitting diode (LED) warning signal light and communication device comprising a controller for generating a first observable light signal and a second non-observable light signal within said first light signal. The second light signal is formed of packets of individual pulsed light which may be processed for comparison to data stored in memory integral to a controller for communication of information to an individual through the use of pulsed light signals.

Abstract: An apparatus and method for combining multiple optical beams into mode-scrambled optical signals. In one embodiment, the apparatus includes a plurality of laser beam sources, each to produce a modulated optical beam. A plurality of input fiber segments, each comprising a multimode optical fiber core, are operatively coupled at one end to a respective laser source to receive a respective modulated optical beam. A multimode optical beam combiner is used to operatively couple the output ends of the input fiber segments to the input end of an output fiber segment having a multimode optical fiber core. The modulated optical beams produced by the laser beam sources are combined into a single mode-scrambled optical signal. The apparatus enables multiple optical beams having similar wavelengths to be combined to increase optical signal strength. It also enables multiple optical beams having different wavelengths to be combined to form a wavelength division multiplexed signal.

Abstract: A holographic optical element (HOE) device is mounted in wireless optical telecommunication system transceiver. The HOE device includes a developed emulsion material having an interference pattern recorded thereon, sandwiched between a pair of elements, such as a pair of clear glass plates. In operation, the HOE device uses the recorded interference pattern to diffract received light rays towards an optical processing unit of the system receiver. A transmitter unit can be positioned at least in part behind the HOE device. An opening in the emulsion material allows a light signal transmitted from the transmitter unit to be substantially unaffected by the recorded interference pattern. The transceiver can also include a spotting scope and an alignment beacon.

Abstract: Optical signals are received from a free-space link by directing received light onto a plurality of microlenses and then directing light received through each of the microlenses into a respective single mode optical fiber (SMF). Light beams from the SMFs are combined into a single light beam in one SMF. The single light beam is amplified with a multi-wavelength fiber amplifier and attenuated with a variable optical attenuator. The power gain of the multi-wavelength fiber amplifier and the attenuation of the variable optical attenuator are controlled. The single light beam is directed into a fiber optic communication system that is optically coupled to the variable optical attenuator.

Abstract: The device enables bi-directional optical communication between a master module and slave modules by means of an optical rod (1) made of transparent material. The master module is axially coupled to the rod. The modules are arranged laterally along a useful part of the rod bounded by a lateral reflector located opposite the slave modules. The lateral reflector can be formed by a plurality of adjacent notches (12) formed at the surface of the rod and constituting a continuous reflecting zone in the form of serrated teeth, and/or by a narrow reflecting strip (17). The slave modules can be positioned anywhere along the useful part of the rod and their lateral location is not critical, a lateral coupling zone extending over at least 1 cm outside the rod. Such a device can be advantageously used in an electrical panel.

Abstract: The present invention provides an apparatus and a method for improved connectivity in wireless optical networks. Therefore at least two or more receiving units are used which receive an infrared signal and convert it to a digital signal. The digital signals represent data in the form of frames whereby each frame comprises at least a data field and a header field containing a preamble. A selector determines a measure related to the signal-to-noise ratio of the preamble and compares the measures in order to select the best suited signal for further processing.

Abstract: A communication system includes a pair free space optical (FSO) terminals. The FSO terminals switch from a first operating mode to a second operating mode wherein the traffic is carried by an ad hoc network. The switching may be based upon a quality of service (QoS) parameter being exceeded. The first operating mode may be the primary operating mode, and the second operating mode may be the back-up operating mode.

Abstract: The present invention involves a method and system for transmitting data in an optical or hybrid optical and RF wireless network from a base structure including a base apparatus to a target device including a target apparatus. The base apparatus includes a base receiver, a laser, a device for positioning the laser-emitted beam, and a base microprocessor. The target apparatus includes a target transmitter, a photodetector, and a target microprocessor. Once the target device comes to a rest beneath the base structure, the target transmitter communicates the presence of the target apparatus to the base receiver. A communication uplink is established between the target apparatus and the base apparatus.

Abstract: An optical space communications device includes a transmitter circuit which assigns an idle code indicating that the device is transmitting no data so that the idle code differs from an idle code for another device and which, when the transmitter circuit continuously transmits such idle codes, inserts, between the idle codes, a random code having a different random pattern from a pattern of the idle codes. Thus, light from another device is distinguished from stray light based on the idle codes. A disconnection of the other device is reliably detected. The insertion of random codes reduces effect of crosstalk jitter.

Abstract: The system and method of the present invention optically transmits redundant packets of data using infrared signals at pseudo-random intervals to allow a receiver to distinguish between multiple simultaneous sources. The emitters repeatedly transmit a short packet at randomized intervals much shorter than the frame rate. Statistical analysis shows that the probability of collision of the desired packet with a packet from some other source is sufficiently low such that timely reception of at least one uncorrupted packet in the required time frame is assured.

Abstract: Disclosed is a novel free space optical communication system comprising an optical amplifier configured to amplify an optical signal received from a fiber optic cable, a transmitter coupled to the optical amplifier and configured to transmit the amplified optical signal across a free space medium. The system also includes a receiver configured to receive the attenuated optical signal and a second optical amplifier coupled to the receiver configured to amplify the attenuated optical signal before transmitting the optical signal on to a fiber optic cable. The optical amplifier is preferably a Raman optical amplifier, but may also be any other optical amplifier, or combination of optical amplifiers, known in the art.

Abstract: The invention concerns a device for modifying the operating conditions of an electronic component comprising an infrared detection system (3-4) which consists in emitting, besides the usual detection signal, a second low-power signal which can only be reflected via a passive reflector (5) located closer to the detection assembly.

Abstract: This disclosure relates to a laser communication system for transmitting intelligence by means of partially coherent optical energy. The system provides improved transmission of intelligence from a transmitter site through non-confined free space and receiving said intelligence at a receiver site remote from and physically separate from said transmitter by non-confined free space. The system has a optical source at the transmitter site for producing a beam of spatially-coherent monochromatic, aperture limited electromagnetic optical energy as well as a modulator for modulating said beam with intelligence-bearing information to develop wavefronts of mutually-aligned orientation which beam is thereafter modified to partial coherence and a receiver site for both detecting said information in said partially coherent beam and deriving said demodulated information. The partially coherent beam has an a of preferably from 0.05 to 0.

Abstract: A free space wavelength duplexed system includes first and second terminals. The first terminal includes an optical transmitter and an optical receiver. The optical receiver has a telescope, an optical to electrical converter and an optical amplifier coupled between the telescope and the optical to electrical converter. A method includes the steps of receiving a received optical signal through a telescope, diverting the received optical signal in an optical splitter into an optical amplifier, and transmitting a transmit optical signal through the optical splitter to the telescope. Another method includes the steps of receiving plural received optical signals through a telescope, diverting the plural received optical signals in an optical splitter into an optical amplifier, separating the plural amplified optical signals by wavelength, and transmitting plural transmit optical signals at distinct wavelengths through the optical splitter to the telescope.

Abstract: A free-space optical communication system utilizes an optical repeater system, which is installed between transmitting terminals and receiving terminals. Each optical receiver of the repeater system connects via a separate optical beam with one or more of the transmitting terminals. Two or more optical transmitters of the repeater system preferably communicate with each of the receiving terminals. Modules of the repeater system are spatially separated far enough from each other to prevent cross-talk between information on the beams, either at the receivers of the repeating system or at the receiving terminals. Receiving elements in the repeater system and/or in the destination receiving system preferably convert angular beam separation into spatial resolution between beam detectors.

Abstract: A communication system includes a plurality of nodes and a plurality of point-to-point links that interconnect the plurality of nodes into a network. Each node includes an optical switch to controllably route a plurality of in-ports of the optical switch into a plurality of out-ports of the optical switch. Each point-to-point link includes a free space optical channel. A first free space optical channel couples to a first node through a receive path and through a transmit path. The receive path couples to a respective in-port of the optical switch of the first node, and the transmit path couples to a respective out-port of the optical switch of the first node. In an alternative embodiment, a communication hub includes a plurality of neighborhood links to corresponding users, an optical switch coupled to the plurality of neighborhood links, and a trunk coupled between the optical switch and a free space optical channel link to the network.

Abstract: A scan acquisition technique for acquiring terminals (62, 64) that does not rely on precise alignment between a sensor (66, 70) and a transmitter (68, 72) associated with the terminals (62, 64). The terminals (62, 64) separate uncertainty regions (76, 78) into a plurality of sections (88, 90). Scan beams (82, 84) include encoded information of what section (88, 90) the scan beam (82, 84) is currently scanning. Each terminal (62, 64) will eventually receive the scan beam (82, 84) of the other terminal (62, 64). When it does, it will encode its scan beam (82, 84) with both the outgoing code and the return code for that section (88, 90), so that when it's scan beam (82, 84) is received by the other terminal (62, 64), that terminal (62, 64) will know what scan section (88, 90) the other terminal (62, 64) is located.

Abstract: Optical communications networks are provided that allow network maintainers to monitor or control subsystems using communications links other than optical telemetry links. The communications links may be wireless links or may be based on any other suitable communications links such as links using Ethernet cables or telephone lines. Network subsystems may be provided that include communications circuitry for communicating over the communications links. A network maintainer may use network control and management software implemented on computer equipment at a different location than the subsystems to communicate with the subsystems over the communications links. Because the communications links may function independently from the optical telemetry channels in the network, new subsystems may be added to the network without disturbing the existing network management software or telemetry arrangement.

Abstract: This disclosure relates to a laser communication system which allows changing the direction of reception and transmission without external manipulation of the system container. The basic unit of the system is a narrow-band transmitting-receiving telescope apparatus which includes a rotating diffraction grating and an independently rotating stage with mounted combination of photodetector for reception and laser for transmission and a focusing system concentrating the beam reflected from the grating onto the photodetector of the combination or sending a beam from laser of the combination onto the grating. The selection of definite angles for signal transmission-reception is realized by corresponding rotation of grating and rotating stage to the proper angles. The apparatus is intended for spectrally selective transmitting or receiving of optical radiation.

Abstract: This invention relates to demultiplexing, routing and multiplexing of a number of different optical wavelength channels. The demultiplexer provides a basis for robust designs of multi-channel optical communication receiver, spectrum analyzer and router. The demultiplexer is operationally bi-directional providing a means for multiplexing.

Abstract: A hybrid wireless optical and radio frequency (RF) communication link utilizes parallel free-space optical and RF paths for transmitting data and control and status information. The optical link provides the primary path for the data, and the RF link provides a concurrent or backup path for the network data, as well as a reliable and primary path for the control and status information. When atmospheric conditions degrade the optical link to the point at which optical data transmission fails, the hybrid communication link switches to the RF link to maintain availability of data communications. The switch may occur automatically, based on an assessment of the quality of the optical signal communicated through the optical path.

Abstract: The present invention provides an apparatus and method for free space optical communication. The apparatus includes a first optical source configured to generate a first optical beam, a first optical beam carrier optically aligned with the first optical source and configured to propagate at least a portion of the first optical beam, and an extended source optically aligned with the first optical beam carrier and configured to output an extended source optical beam. The extended source can include an extended source telescope configured to direct at least a portion of the first optical beam to output the extended source optical beam into free-space. Alternative the extended source can include a large core fiber optic cable configured to propagate at least a portion of the first optical beam exercising additional modes of the large core fiber cable to generate the extended source optical beam.

Abstract: The present invention provides a method and apparatus for free-space optical communication. The method comprises the steps of receiving a receive optical beam through a narrow field of view, determining a receive power level, shifting an alignment, maximizing the receive power, and transmitting a transmit optical beam along the alignment, wherein the narrow field of view is less than a divergence of the transmit optical beam. The narrow field of view can be a narrow region of a multi-region field of view. The apparatus comprises an optical beam transmitter configured to generate a narrow diverging transmit beam, a narrow field of view optical receiver, wherein the field of view is less than the divergence of the transmit beam, and a controller configured to determine a power level of a receive beam and to determine adjustments to a direction of transmission maximizing receive power.

Abstract: An infrared transmission/reception apparatus and a method thereof in which an infrared transmission output is changed to transmit a plurality of station finding commands, and an infrared transmission output for such a station finding command out of the plurality of station finding commands as returning a station finding response from a secondary station is used to perform a subsequent communication. Thus, communication can be performed with the minimum infrared output regardless of the opposite apparatus.

Abstract: Free space optical communications systems operable at elevated temperatures include a special highly sensitive, low noise LWIR detector. The optical train is terminated at a special detector arrangement where a semiconductor photodetector and optical immersion type lens are combined and highly integrated as a single element. The detector active region is much smaller than comparable devices which affords a low noise factor critical in IR systems to be operated at high temperature.