Abstract: Methods, devices, and systems are described for free space optical communication. An example method can comprise generating a first linearly polarized optical signal having a wavelength and a first type of linear polarization and converting the first linearly polarized optical signal to a first circularly polarized optical signal. The first circularly polarized optical signal can be output into free space. The method can comprise converting a second circularly polarized signal, received via free space using the wavelength, to a second linearly polarized optical signal. The second linearly polarized optical signal can have a second type of linear polarization different than the first type. The method can comprise directing, via a polarizing beam splitter, the second linearly polarized optical signal to one or more detectors configured to output data.

Abstract: Disclosed in some examples, are optical devices, systems, and machine-readable mediums that send and receive multiple streams of data across a same optical communication path (e.g., a same fiber optic fiber) with a same wavelength using different light sources transmitting at different power levels—thereby increasing the bandwidth of each optical communication path. Each light source corresponding to each stream transmits at a same frequency and on the same optical communication path using a different power level. The receiver differentiates the data for each stream by applying one or more detection models to the photon counts observed at the receiver to determine likely bit assignments for each stream.

Abstract: Embodiments disclosed herein address these and other issues by providing for an optical tag that uses an optical assembly with beam splitters to allow for simultaneous detection and retro-modulation, as well as the use of a camera to facilitate alignment of the optical tag with a laser interrogator. Additional components may be used to allow for a large aperture to be used, to help maximize light received by the optical tag and minimize diffraction of retro-modulated light, which can significantly increase distances at which the optical tag can operate. Moreover, a beam splitter may further be used to balance the light directed toward an optical sensor and a retro-modulator, to help achieve optimal results.

Abstract: An optical transceiver device is provided, including an O/E transceiver module, an optical switching module and a switching control module, for providing network communication services for a first and a second optical fiber network equipment. The O/E transceiver module is an integrated chip having multiple transceiver units integrated therein. The switching control module is connected to an in-line equipment and the optical switching module for controlling the optical switching module to execute corresponding optical path switching operation according to an optical path switching control signal output from the inline equipment. In comparison with conventional optical transceiver devices, the invention is advantageous of simple structure, smaller volume and more flexible optical path switching.

Abstract: An optical transceiver device is provided, including an O/E transceiver module, an optical switching module and a switching control module, for providing network communication services for a first and a second optical fiber network equipment. The O/E transceiver module is an integrated chip having multiple transceiver units integrated therein. The switching control module is connected to an in-line equipment and the optical switching module for controlling the optical switching module to execute corresponding optical path switching operation according to an optical path switching control signal output from the inline equipment. In comparison with conventional optical transceiver devices, the invention is advantageous of simple structure, smaller volume and more flexible optical path switching.

Abstract: According to one embodiment, a wireless tag communication device detects a communication state between an antenna and a specific wireless tag to be searched, stores a transmission power value obtained if the communication state is better than a predetermined value, reduces transmission power to the wireless tag and, if the communication state is worse than the predetermined value, increases, on the basis of the stored transmission power value, the transmission power to be higher than the transmission power value and performs communication with the wireless tag, and performs resetting on the basis of the stored transmission power value if the communication state further worsens.

Abstract: A communication system includes: a remote controller having an input unit inputting user operations and a communication unit performing bidirectional communication, transmitting a remote control code in accordance with the user operation with respect to the input unit from the communication unit; and a host device having a communication unit performing bidirectional communication and a host function unit executing processing corresponding to the remote control code received in the communication unit, wherein the host device transmits a status response from the communication unit in response to a status inquiry transmitted from the communication unit of the remote controller, the remote controller repeatedly executes a status check communication procedure including the transmission of the status inquiry and waiting for receiving the status response after transmitting the remote control code at given time intervals during which the communication unit is in a dormant state.

Abstract: A free space optical communications link node 10 comprising transmitter apparatus 12 comprising a first optical transmitter 14, arranged to transmit high priority traffic on a first upstream optical signal having a first wavelength and at a first optical signal power, and a second optical transmitter 16 arranged to transmit low priority traffic on a second upstream optical signal having a second wavelength, different to the first wavelength, and at a second optical signal power. The node 10 further comprises receiver apparatus 18 comprising a first optical amplifier 20 arranged to receive and amplify a first downstream optical signal having a third wavelength and carrying high priority traffic and a second downstream optical signal having a fourth wavelength, different to the third wavelength, and carrying low priority traffic.

Abstract: A free space optical communication system (100) and method including: several optical beam expanders (414) for receiving incoming optical signals from ground sites and neighboring satellites; several optical preamplifiers (412) for preamplifying the received optical signals; one or more optical main amplifiers (404) for amplifying the preamplified optical signals; and an optical switch (408) for directing respective amplified optical signals to respective destinations via a respective optical beam expander. The respective amplified optical signals are inputted to a respective optical beam expander (414) for transmission to said respective destinations, as outgoing optical signals.

Abstract: A transmission apparatus of a wireless light communication system using an illumination light source can maximize a rate of data transmission while maintaining a brightness adjusting function of the illumination light source. The transmission apparatus includes a dimming level input unit which receives a dimming level of the illumination light source as an input, a coder which codes original data and outputs the coded data, a dimming coder which checks the dimming level input to the dimming level input unit, generates a symbol-codeword table corresponding to the dimming level, and dimming-codes the data output from the coder, a line coder which converts the data diming-coded by the dimming coder into pulse signals.

Abstract: A wireless communications link comprising an RF link and a free space optics (FSO) link, a switch, an RF signal monitoring apparatus, an optical signal monitoring apparatus, alarm apparatus and a controller. The switch operates in a normal mode to aggregate the links to form a link aggregation group and to route traffic on the link aggregation group, a first protection mode to route traffic on the FSO link, or a second protection mode to route traffic on the RF link. The controller is arranged to receive an alarm signal and to generate and transmit a control signal to cause the switch to operate in the first protection mode when a first alarm signal is received, the second protection mode when a second alarm signal is received, and the normal mode when an indicator is received indicating that both signal quality parameters are above their threshold values.

Abstract: A system for delivering optical power over optical conduits includes at least one optical power source delivering multiple optical power forms to multiple outlet nodes in a variety of applications.

Abstract: A system for open space data communication comprising a transmitting device and an optical receiver using multiple varying levels of emitted radiation output. The transmitting device includes multiple emitter groups that are capable of being switched on and off and each of which can be activated in parallel to emit fixed, varying radiation outputs. A total radiation output emitted by the transmitting device is defined by a sum of the emitted radiation outputs of the emitter groups, wherein to transmit a bit vector (b0 . . . bn) an emitter group assigned to a most significant bit (b0) emits a maximum radiation output Pmax and emitter groups assigned to the less significant bits (b1 . . . bn) of the bit vector emit radiation outputs: Px=Pmax/2x where x=1 . . . n.

Abstract: For use in a visible light communication (VLC) network, a method for generating high resolution visibility frames for visibility or dimming support. The method includes determining a required visibility for the high resolution frames. The method also includes generating a pattern that meets the determined required visibility, the pattern having a first quantity of first low resolution frames and a second quantity of second low resolution frames. The method further includes transmitting the pattern to achieve the required high resolution frames.

Abstract: A free space optical communications link node 10 comprising transmitter apparatus 12 comprising a first optical transmitter 14, arranged to transmit high priority traffic on a first upstream optical signal having a first wavelength and at a first optical signal power, and a second optical transmitter 16 arranged to transmit low priority traffic on a second upstream optical signal having a second wavelength, different to the first wavelength, and at a second optical signal power. The node 10 further comprises receiver apparatus 18 comprising a first optical amplifier 20 arranged to receive and amplify a first downstream optical signal having a third wavelength and carrying high priority traffic and a second downstream optical signal having a fourth wavelength, different to the third wavelength, and carrying low priority traffic.

Abstract: Disclosed is a method for setting a power control initial value by using an indication light in visible light communications and a transmission/reception (Tx/Rx) apparatus using the method. The method includes the steps of: radiating multiple indication lights having power levels different from one another by a visible light communication transmitter; aligning a communication position simultaneously with measuring Received Signal Strength Indication (RSSI) of the indication light on detecting the indication light, selecting a power level whose RSSI is in a preset threshold range and which is adequate for transmission/receive among the multiple power levels different from one another, and informing the visible light communication transmitter of the adequate power level by a visible light communication receiver; and transmitting data from the visible light communication transmitter to the visible light communication receiver by using a transmitted power initial value according to a selected power level.

Abstract: An optical communication serial interface is employed to power up a device from a powered down state to a powered on state. An optical receiver element receives serial optical signals transmitted by at least one optical fiber and converts the received serial optical signals to electrical signals. A low level reception converter detects and decodes the electrical signals to provide data and control words from detected and decoded normal electrical signals for a high level command processor. A power supply maintains low level power to at least the optical receiver element and the low level reception converter of the optical communication serial interface while the device is in the powered down state. The low level reception converter detects a particular abnormal sequence of electrical signals; and in response to detecting the particular abnormal sequence of electrical signals, asserts a control signal to power up the device controllable power supply.

Abstract: A system for delivering optical power over an optical conduit includes at least one than one optical power source delivering multiple optical power forms at least partially over a free space.

Abstract: Visible light data communication with a sufficient transmission speed is performed using a general-purpose and cost-advantageous blue-light-excitation-type white LED without using a blue color filter while preventing the element from being damaged. When transmission data is inputted to a driving waveform generation unit (110) in a transmitter (100), the driving waveform generation unit (110) and a multi-gray scale driving unit (120) generate a multi-gray scale driving signal, which is supplied to the blue-light-excitation-type white LED (140) and allows the blue-light-excitation-type white LED (140) to emit light. A light signal outputted from the blue-light-excitation-type white LED (140) is collected by a lens or the like, is made incident into a PD (210) in a receiver (200), and is converted to a current signal. The current signal is converted into a voltage signal in a trans-impedance amplifier (212).

Abstract: A method for generating a visible signal for a data transmission frame in a visible-light communication system includes: receiving specific data constituted by a plurality of frames from a sender; checking and converting a received signal strength indication (RSSI) signal measured from the sender; whenever each frame of the specific data is consecutively received, checking the converted RSSI, determining a level of a visible signal for distinctively displaying a state of a corresponding communication channel, and transmitting the level of the visible signal to the sender; and when reception of the specific data has finished, transmitting a corresponding response message to the sender, according to whether the specific data has been successfully received.

Abstract: An optical communication serial interface is employed to power up a device from a powered down state to a powered on state. An optical receiver element receives serial optical signals transmitted by at least one optical fiber and converts the received serial optical signals to electrical signals. A low level reception converter detects and decodes the electrical signals to provide data and control words from detected and decoded normal electrical signals for a high level command processor. A power supply maintains low level power to at least the optical receiver element and the low level reception converter of the optical communication serial interface while the device is in the powered down state. The low level reception converter detects a particular abnormal sequence of electrical signals; and in response to detecting the particular abnormal sequence of electrical signals, asserts a control signal to power up the device controllable power supply.

Abstract: A radio-frequency (RF) remote control (10) has a user interface and transmits an RF signal (11) which designates a device (14) to be controlled and a command for that device. The RF signal is received by an intermediary device (12). The intermediary device, in turn, generates and broadcasts a plurality of high-power IR signals (13A-13F). These signals may be received directly by a controlled device (14A) or may be received indirectly by a controlled device (14B, 14C) after one or more reflections from objects (16A, 16B) and/or room surfaces (18). Thus, reliable control of the devices (14) is obtained even in situations where merely transmitting a typical IR signal may not provide reliable control of the device (14).

Abstract: An optical receiver for visible light communication includes a lens system for converging visible light for light communication and an optical filter for passing converged visible light to the optical receiver. A photoelectric transmission device detects data from visible light for light communication in a VLC system. An optical filter is positioned between the lens system and the photoelectric transmission device, the optical filter having a first film for transmitting visible light and a second film arranged/grown around the first film to transmit ultraviolet rays or infrared rays. A first optical detects data from visible light passing through the first film of the optical filter. A second optical detector detects the intensity of light transmitting the second film. The encoding, encoding rate or intensity of the optical transmitted signal can be adjusted in response to the detection of at least the second optical detector.

Abstract: At least a plurality of light-receiving regions for receiving remote control signals, respectively, in a form of incident light and performing photoelectric conversion of the signals are provided in one common mold package. The remote control receiver includes a first signal processing circuit for adding up signals outputted by the plurality of light-receiving regions and, based on a resulting signal, demodulating and outputting the remote control signal. The remote control receiver also includes a second signal processing circuit for calculating a difference between the signals outputted by the plurality of light-receiving regions to obtain and output a directional signal representing a direction in which the incident light has been incident on the plurality of light-receiving regions.

Abstract: Disclosed is a short-distance communication method and an apparatus using visible light. The apparatus scans ambient light, measures optical power of visible light, among visible light included in the ambient light, having a wavelength corresponding to a transmission wavelength used for the visible light communication, compares a minimum transmission optical power of transmitted light, a real transmission optical power, and the measured optical power of the ambient light, selects a transmission wavelength of the transmitted light on which noises caused by the ambient light have little effect, and performs the visible light communication using the visible light of the selected transmission wavelength.

Abstract: A system according to embodiments of the invention may include a first communication path that converts an optically-modulated source signal to a radio signal based on a detected degradation in a quality of a received optical signal, and a second communication path that converts a radio-modulated source signal to an optical signal based on a detected degradation in a quality of a received radio signal. The system has the ability to automatically adapt to diverse weather conditions to improve the reliability of a communication link without user intervention while supporting multiple modulation schemes.

Abstract: Power control circuitry is provided for controlling an output power of a transmitter of a mobile terminal operating according to a continuous time transmit scheme such as Wideband Code Division Multiple Access (WCDMA). Transmit circuitry processes a quadrature baseband signal to provide a radio frequency transmit signal. The radio frequency transmit signal is coupled to the power control circuitry via a coupler and processed to provide a feedback amplitude signal. The power control circuitry operates to remove an amplitude modulation component from the feedback signal using a reference amplitude signal generated from the quadrature baseband signal, thereby providing a measured gain signal of the transmit circuitry. Based on the measured gain signal and a target output power, the power control circuitry operates to control a gain of the transmit circuitry such that the output power of the transmit circuitry is within a predetermined range about the target output power.

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: An optical transmission apparatus is provided in which high optical output power is secured in an optical transmitter, the fine adjustment of the optical axis is unnecessary, and the propagation range of the optical output signal can be adaptively changed. A diffusing liquid lens includes a first liquid and a second liquid containing a scattering material that scatters light, and the curvature of the boundary surface between the first and the second liquids is changed according to the control voltage applied from a controlling unit. A first optical signal outputted from a light emitting device is diffused in the first liquid, and emitted as a second optical signal having a spread angle corresponding to the curvature of the boundary surface and a substantially uniform radiant intensity distribution.

Abstract: Field devices comprising a transmitter and/or receiver for wireless data communication are provided. The energy available for wireless data communication in data transmitting or data receiving field devices is evaluated prior to activation of the transmitter and/or receiver of the field device.

Abstract: The invention relates to a wireless optical data transmission system and a method for wireless optical transmission of data. The system comprises a data stream generator for generating at least two parallel data streams (18.1, 18.2, 18.3). The parallel data streams are transmitted by a number of separate optical transmitting devices (8, 9, 10) separately by emitting first optical signals. The system further comprises a corresponding number of detectors (19, 20, 21) for detecting the first optical signals and converting them into respective second signals (26.1, 26.2, 26.3) and an error correction unit (31) for correcting the amended second signals. Within a predistortion (29) unit each second signal (26.1, 26.2, 26.3) is amended individually with respect to a transmission channel used.

Abstract: A method and device produce an optical link with laser pulses between an emitter of the pulses and a receiver of the pulses. The optical link is used by a locating device for locating a body moving at constant speed away from the locating device. The locating device delays the start of emission of the laser pulses with respect to the departure of the moving body and varies the energy of the successive laser pulses in proportion to the square of the time elapsed since the start of emission of the pulses.

Abstract: Systems and methods for use with an optical communication beam are disclosed. The system allows the beam of light to operate at an adequate power level that provides a robust optical link while minimizing any safety risk to humans. The system calibrates and controls the gain for an avalanche photodiode detector (APD). A detector circuit is used to calibrate the APD. Once calibrated, the detector circuit further provides an electrical bias to the APD to process or condition the electrical signal to produce a detector output. The systems and methods disclosed herein attenuate the power level of an incoming communication beam to prevent oversaturation of an APD. The system further provides an alignment signal, which is effective over a wide dynamic range of incoming power levels.

Abstract: In an adaptive optics module, wavefront sensing and data detection are implemented in a single device. For example, an optical-to-electrical converter converts a data-encoded optical beam to an intermediate electrical signal, which contains both the data encoded in the beam and also wavefront information about the beam. The data and wavefront information are later separated, for example by frequency filtering.

Abstract: A fiber optic phased array and control method are provided for controllably adjusting the phase and amplitude of the optical signals emitted by a plurality of fiber optic amplifiers to compensate for atmospheric turbulence. The fiber optic phased array also includes a sensor assembly for detecting: (i) the phase of the optical signals that are emitted by the fiber optic amplifiers, and (ii) both the phase and the amplitude of the optical signals that have been reflected by the target. The fiber optic phased array also includes phase modulators and a gain adjustment mechanism for altering the phase and the amplitude of the optical signals propagating along the fiber optic amplifiers to compensate for modifications in the phase and amplitude that will be introduced by atmospheric turbulence. Among other things, the amplitude control of the optical signals is not adversely effected by intensity nulls in the reflected wavefront.

Abstract: The extended range of optical data communication is enabled through the use of intermediary relay stations spaced fairly far apart. IRDA communicatiOn, as is well known, uses very short duration optical pulses to send data up to 1 Mbit/sec; this has the concomitant effect of minimizing LED duty cycle and preventing excessive heating. The invention uses a number of integrated pulses to represent a single bit instead of utilizing a one-to-one correspondence between pulses and bits. Processing software causes the 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 as signal intensity drops by a factor of 100 when distance increases by a factor of 10 yielding a distance/intensity ratio of 1/10.

Abstract: A free space optical communication system includes an adaptive optical power regulator. The adaptive optical power regulator adapts to changes in effective loss associated with the free space optical path. In one embodiment the adaptive optical power regulator adapts to scintillation losses. In another embodiment, the adaptive optical power regulator further adapts to changes in atmospheric loss associated with changes in weather.

Abstract: A method and apparatus for compensating for phase fluctuations incurred by an optical beam travelling through free space, especially a turbulent atmosphere. A transmitting station transmits a plurality of uniquely tagged optical beams through free space. The plurality of uniquely tagged optical beams are received at a receiving station, where a parameter of each uniquely tagged optical beam is quantified. Information associated with the quantified parameter for each uniquely tagged optical beam is then sent back to the transmitting station via a wireless feedback link. Using the information, the transmitting station adjusts at least one uniquely tagged optical beam to compensate for phase fluctuations.

Abstract: A system according to embodiments of the invention may include a first communication path that converts an optically-modulated source signal to a radio signal based on a detected degradation in a quality of a received optical signal, and a second communication path that converts a radio-modulated source signal to an optical signal based on a detected degradation in a quality of a received radio signal. The system has the ability to automatically adapt to diverse weather conditions to improve the reliability of a communication link without user intervention while supporting multiple modulation schemes.

Abstract: An optical communication system is provided which includes an optical signal transmitter which communicates high bandwidth, high power frequencies. The optical signal transmitter includes a high efficiency/high power optical source such as an optical magnetron or a phased array source of electromagnetic radiation, and a modulator element. The modulator element may be within a resonance cavity of the high efficiency/high power optical source (intra cavity) or external to the cavity (extra cavity). The modulator element serves to modulate output radiation of the high efficiency/high power optical source to produce a modulated high frequency optical signal which may be transmitted through the air. The optical signal transmitter is particularly useful in providing the last mile connection between cable service operators and end users.

Abstract: Field devices comprising a transmitter and/or receiver for wireless data communication are provided. It is proposed to evaluate the energy available for wireless data communication in data transmitting or data receiving field devices prior to activation of the transmitter and/or receiver of the field device.

Abstract: Systems and methods for use with an optical communication beam are disclosed. The system allows the beam of light to operate at an adequate power level that provides a robust optical link while minimizing any safety risk to humans. The system calibrates and controls the gain for an avalanche photodiode detector (APD). A detector circuit is used to calibrate the APD. Once calibrated, the detector circuit further provides an electrical bias to the APD to process or condition the electrical signal to produce a detector output. The systems and methods disclosed herein attenuate the power level of an incoming communication beam to prevent oversaturation of an APD. The system further provides an alignment signal, which is effective over a wide dynamic range of incoming power levels.

Abstract: A repeating apparatus and method using wireless optical transmission is disclosed. The repeating apparatus includes a donor device for transmitting two identical copies of an optical signal by receiving a RF signal from a base station and electro-optic converting the RF signal to an optical signal, and for transmitting a RF signal by receiving two identical copies of the optical signal and optic-electro converting the optical signal to a RF signal; and a coverage device for transmitting a RF signal to a mobile communication terminal by receiving two identical copies of the optical signal from the donor device and optic-electro converting the two identical copies of the optical signal to the RF signal, and transmitting two optical signals to the donor device by receiving the RF signal from the mobile communication terminal and elector-optic converting the RF signal to the optical signal.

Abstract: A system and method for use with an optical communication beam of light is disclosed. The system allows the beam of light to operate at an adequate power level that provides a robust optical link while minimizing any safety risk to humans. Such a system includes multiple operating modes which control the power output of the beam of light. In the normal mode, the beam of light operates at a selected power level which provides a desired signal to noise ratio. Once a blocking occurs, the beam of light enters a power reduction mode to prevent harm to the blocking object. An acquisition and recovery mode is then employed to reestablish the blocked communication link.

Abstract: The invention relates to a system for conveying digital signals inside a space vehicle between a transmitter and a receiver. In the invention, the link between the transmitter and the receiver comprises a first portion made of optical fiber and a second portion in which infrared radiation propagates without guidance. A particular application lies in conveying remote control and telemetry signals within a satellite between a control module and a piece of equipment.

Abstract: Systems and methods for regulating optical power are described. A system for regulating optical power includes a laser driver circuit that receives an enable/disable signal and a data modulator input. The enable/disable signal regulates asynchronous mode operation. The system also includes a laser module including a laser diode emitter and a photodiode detector. The laser module is coupled to the laser driver circuit and receives a laser bias current from the laser driver circuit. The system also includes a switch coupled to the photodiode to receive a signal from the photodiode detector. The system also includes an automatic power control (APC) feedback circuit that receives a signal from the switch and provides a laser bias current feedback signal to the laser driver circuit to compensate for power output changes in the laser diode emitter over time.

Abstract: An Improved Infrared Signal Communication System and Method Including Transmission Means Having Automatic Gain Control is disclosed. Also disclosed is system and method that adjusts signal transmission power in response to incident signal power amplitude. The preferred system includes a control signal loop within the signal receiving system, and the system further includes a signal transmitting system that is responsive to the control signal loop. The preferred system includes manual, semi-automatic and automatic modes of operation. Still further, the preferred method includes at least two Ir-enabled appliances “stepping” each other “down” in transmit power in response to directives issued by the other Ir-enabled appliance.

Abstract: This invention provides a dynamic interconnection system which allows to couple a pair of optical beams carrying modulation information. In accordance with this invention, two optical beams emanate from transceivers at two different locations. Each beam may not see the other beam point of origin (non-line-of-sight link), but both beams can see a third platform that contains the system of the present invention. Each beam incident on the interconnection system is directed into the reverse direction of the other, so that each transceiver will detect the beam which emanated from the other transceiver. The system dynamically compensates for propagation distortions preferably using closed-loop optical devices, while preserving the information encoded on each beam.

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: 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.