It discloses a precise locating method of utilizing indoor visible light communication system, which belongs to the field of visible light communication; arranging any number of light emitting diode (LED) lamps indoors, setting the signal transmission power of each LED lamp to be the same and fixing the absolute location of each LED lamp, the terminal required for locating is equipped with several receiving devices, whose relative positions are known, then a position coordinate of the terminal can be obtained by determining the geometric center position of this set of receiving devices through calculating the measured light signal power of the receiving devices on the terminal.

It discloses a precise locating method of utilizing indoor visible light communication system, which belongs to the field of visible light communication; arranging any number of light emitting diode (LED) lamps indoors, setting the signal transmission power of each LED lamp to be the same and fixing the absolute location of each LED lamp, the terminal required for locating is equipped with several receiving devices, whose relative positions are known, then a position coordinate of the terminal can be obtained by determining the geometric center position of this set of receiving devices through calculating the measured light signal power of the receiving devices on the terminal.

A system and method for transmitting a wavelength division multiplexed (WDM) signal on an optical transmission path. The system includes at least one first modulation format transmitter configured to generate an associated first modulation format signal on an associated signal wavelength using a first modulation format having a first spectral efficiency, and at least one second modulation format transmitter configured to generate an associated second modulation format signal on an associated signal wavelength using a second modulation format having a second spectral efficiency higher than the first spectral efficiency. The second modulation format signals having an optical power set nominally higher than the optical power of the first modulation format signals. The first and second modulation format signals are combined into an aggregate output signal on the optical transmission path.

A system and method for transmitting a wavelength division multiplexed (WDM) signal on an optical transmission path. The system includes at least one first modulation format transmitter configured to generate an associated first modulation format signal on an associated signal wavelength using a first modulation format having a first spectral efficiency, and at least one second modulation format transmitter configured to generate an associated second modulation format signal on an associated signal wavelength using a second modulation format having a second spectral efficiency higher than the first spectral efficiency. The second modulation format signals having an optical power set nominally higher than the optical power of the first modulation format signals. The first and second modulation format signals are combined into an aggregate output signal on the optical transmission path.

Systems and methods for determining margin in an optical network include changing powers of signals from one or more transmitters; measuring noise at one or more receivers each communicatively coupled to the one or more transmitters; and determining margin between the one or more transmitters and the one or more receivers based on the associated measured noise. The changing, the measuring, and the determining are performed in-service while the one or more transmitters are each transmitting data-bearing signals.

Systems and methods for determining margin in an optical network include changing powers of signals from one or more transmitters; measuring noise at one or more receivers each communicatively coupled to the one or more transmitters; and determining margin between the one or more transmitters and the one or more receivers based on the associated measured noise. The changing, the measuring, and the determining are performed in-service while the one or more transmitters are each transmitting data-bearing signals.

An optical transmission device in an optical network in which a first optical path and a second optical path are set, the optical transmission device locating on the second optical path, the optical transmission device includes; a storage unit configured to store control data for a control of an optical transmission power to the second optical path, the control being performed based on a training signal received through the second optical path; and a controller configured to control the optical transmission power to the second optical path, based on the control data stored in the storage unit, according to a detection of an optical path change by which an optical path transmitting a main signal is changed from the first optical path to the second optical path.

An optical transmission device in an optical network in which a first optical path and a second optical path are set, the optical transmission device locating on the second optical path, the optical transmission device includes; a storage unit configured to store control data for a control of an optical transmission power to the second optical path, the control being performed based on a training signal received through the second optical path; and a controller configured to control the optical transmission power to the second optical path, based on the control data stored in the storage unit, according to a detection of an optical path change by which an optical path transmitting a main signal is changed from the first optical path to the second optical path.

An optical transmission apparatus includes: a wavelength selecting switch, including an input port and an output port having more ports than the input port, configured to perform an adjustment of a level of an optical signal from the input port to the output port; a first monitor configured to monitor the level of the optical signal at the input port unit; a second monitor configured to monitor the level of the optical signal at the output port unit; and a controller configured to control the wavelength selecting switch wherein the controller: calculates a virtual output value for the output port unit based on a first monitor result from the first monitoring unit, a second monitor result from the second monitoring unit, and a current adjustment value for the adjustment function; calculates a new adjustment value based on the virtual output value; and sets the new adjustment value to the adjustment.

The invention discloses a system for the bidirectional communication of digital data through the visible light spectrum, in an unconfined medium which uses two devices for supplying electrical current, regulating the voltage, converting the negative voltage, amplifying the signal, transmitting the signal to an LED, receiving the signal, finally converting the signal and transmitting the digital signal wirelessly to an end device, as specified in the description, and which, as a result of its characteristics of innocuity, privacy, low cost, higher power, savings in energy, interactivity, duality of use and extension of useful life of the devices, has a wide range of use in various fields in the industry such as: health, medicine, the military, education, training, tourism, gadget production, to name just a few.

This invention solves the problems of connection, privacy and frequency amplitude of data transmission that are found in existing connections such as Bluetooth and Wi-Fi.