A method for detecting an optical network unit (ONU) in a passive optical network (PON), an ONU, a PON and an optical line terminal (OLT) are disclosed. In an embodiment the method include detecting an ONU identity code in an open uplink empty window or an empty timeslot, wherein the ONU identity code is a specific code stream sequence of the ONU that identifies a single ONU of the plurality of ONUs included in the PON system during the open uplink empty window or the empty timeslot and determining that the single ONU corresponding to the ONU identity code is a rogue ONU according to the ONU identity code.

Techniques are disclosed for emitting position information from luminaires. Luminaire position information may be emitted via a light-based communication (LCom) signal that comprises data including the position information. The data may include relative and/or absolute position information for the luminaire and may indicate the physical location of the luminaire. Relative position information for the luminaire may include coordinates relative to a point of origin within the environment. Absolute position information for the luminaire may include global coordinates for the luminaire. In some cases, the absolute position information for a luminaire may be calculated using position information for the luminaire relative to a point of origin and the absolute position of the point of origin. The data may also include an environment identifier, which may indicate a map to use for the interpretation of position information for the luminaire. The techniques can be used for both stationary and mobile luminaires.

A Dual Parallel (DP)-Inphase/Quadrature (I/Q) Mach-Zehnder Modulator (MZM) bias controller configured to generate a pair of orthogonal dither signals; multiply the pair of dither signals to create a second order orthogonal dither signal; and lock an Inphase (I) I MZM of a DP-I/Q MZM to a value of a corresponding I component of a transmission signal by applying the pair of orthogonal dither signal to a Quadrature (Q) MZM and a Phase (P) MZM of the DP-I/Q MZM; applying an I bias signal to the I MZM of the DP-I/Q MZM; detecting an output of the DP-I/Q MZM; and determining an I error signal in the output of the I MZM of the DP-I/Q MZM based on the product of second order dither signal and the output of the DP-I/Q MZM.

Provided are a fiber-to-the-home implementing method and device. The method includes: receiving, by a virtual Passive Optical Network Medium Access Control (PON MAC) of an Optical Network Unit (ONU), a first packet from an Optical Line Terminal (OLT), determining that the first packet matches the virtual PON MAC, and searching a preset corresponding relationship for a first buffer area corresponding to the virtual PON MAC receiving the first packet; buffering, by the ONU, the received first packet in the searched first buffer area; and sending, by the ONU, the first packet in the first buffer area to a user via a User Network Interface (UNI) corresponding to the first buffer area.

A station-side device performs transmission and reception of an optical signal to and from a subscriber-side device, and includes a communication control unit configured to perform optical signal communication using a plurality of wavelengths by wavelength division multiplexing and time division multiplexing; and a registration unit configured to set an acceptance period in at least one wavelength among the plurality of wavelengths, to perform a new registration of a subscriber-side device in response to a registration request of the subscriber-side device received within the acceptance period, and not to set the acceptance period in at least one other wavelength among the plurality of wavelengths.

Disclosed is a system and method for using visible light communication (VLC) to perform indoor position location. Through use of a system and method configured as set forth herein, the position of any appropriately marked person or item may be found indoors using data interconnected modules that communicate with one another via RF and visible light. A mobile receiver in the form of a tag or badge attached to the person or item to be tracked receives a VLC signal from a plurality of lighting modules, and transmits back to a processor the data it received so that the processor is able determine the tag's or badge's physical position with respect to the individual network modules.

Techniques are disclosed for determining a light-based communication (LCom) receiver position. The techniques can be used to determine the position of a receiver relative to a specific luminaire within the field of view (FOV) of the receiver camera. The relative position may be calculated by determining the distance and the orientation of the receiver relative to the luminaire. The distance relative to the luminaire may be calculated using the observed size of the luminaire in an image generated by the receiver camera, the image zoom factor, and actual geometry of the luminaire. The orientation relative to the luminaire may be determined using a fiducial associated with the luminaire that can be used as an orientation cue. Once the position of a receiver relative to a luminaire is determined, the absolute position of the receiver may be calculated using the absolute position of the luminaire.

Provided are a device unit, a node device, and a method and a system for automatically adjusting a tunnel bandwidth. The device unit includes: a client side element, configured to dynamically adjust The quantity of the first timeslots according to a bandwidth of a received data service before the received data service is mapped to an Optical Channel Data Unit (ODU) tunnel; a line side element, configured to configure, according to the quantity of the first timeslots adjusted by the client side element, The quantity of the second timeslots matched with the first timeslots; a tunnel managing element, configured to adjust, according to the quantity of the first timeslots and the quantity of the second timeslots, the quantity of unblocked ODU tunnels between the client side element and the line side element, wherein unblocked ODU tunnels after the adjustment carry the data service. When the bandwidth of the received data service increases or decreases, the device unit of the present disclosure flexibly controls usage of an ODU0 timeslot in an ODU of each stage, and does not need to use a complicated ODUflex frame format, thereby meeting the requirement of automatically adjusting the bandwidth without using ODUflex.

Techniques are disclosed for providing proper raster line alignment of a camera or other light-sensing device of a receiver device relative to a transmitting light-based communication (LCom)-enabled luminaire to establish reliable LCom there between. In accordance with some embodiments, proper alignment can be provided automatically (e.g., by the receiver device and/or other suitable controller). In accordance with some embodiments, proper alignment can be provided by the user. In some instances in which a user is to be involved in the alignment process, the receiver device may be configured, for example, to instruct or otherwise guide the user in the process of properly aligning the receiver device relative to a given transmitting LCom-enabled luminaire.

Optical signals with different orbital angular momentum (OAM) modes are used to multiplex data directed to different receiver together using time division multiplexing. The OAM based multiplexing may be used in addition to other multiplexing schemes such as time division multiplexing, polarization multiplexing and so on. Capacity of existing optical network infrastructure can be increased significantly using OAM modulation, and data communication can be secured at the same time.