Abstract: A transmitting apparatus includes a plurality of code spreaders different in spreading code, a reception processing unit that selectively distributes transmission data to the plurality of code spreaders, a plurality of optical transmitters each of which that transmit a code-spread signal to an optical fiber as a CDMA optical signal of a carrier wavelength different from that of the other optical transmitters, and a signal multiplexing unit that selectively supplies outputs of the plurality of code spreaders to the plurality of optical transmitters, and a receiving apparatus includes an optical receiver that receives a wavelength-division-multiplexed CDMA optical signal from the optical fiber, and a plurality of despreaders connected to the optical receiver and different in spreading code, wherein each of the despreaders reproduces a CDMA signal corresponding to its spreading code from an output signal of the optical receiver.

Abstract: A system and a method for quantum key distribution between a transmitter and a receiver over wavelength division multiplexing (WDM) link are disclosed. The method includes providing one or more quantum channels and one or more conventional channels over the WDM link; assigning a different wavelength to each of the one or more quantum channels and each of the one or more conventional channels; transmitting single photon signals on each of the one or more quantum channels; and transmitting data on each of the one or more conventional channels. The data comprises either conventional data or trigger signals for synchronizing the transmission of the single photon signals on the quantum channels. All channels have wavelengths around 1550 nm. The WDM link can be a 3-channel WDM link comprising two quantum channels for transmitting single photon signals and one conventional channel for transmitting conventional data or triggering signals.

Abstract: An object of the present invention is to implement optical multiplexing transmission and reception in which an OCDM channel is added without changing the used wavelength bandwidth of the existing WDM channel or without changing the time slot allocated to the existing OTDM channel. Hence, one of the embodiments of the present invention is constituted as follows. The OCDM signal generation section generates an encoded optical pulse signal by encoding an optical pulse signal. The encoded optical pulse signal is inputted to the wavelength disperser and the time waveform of the encoded optical pulse signal is shaped to be outputted as a shaped and encoded optical pulse signal. The WDM signal generation section generates an optical wavelength division multiplexing signal. The OCDM signal extraction section decodes the OCDM reception signal by using the same code as the time-spreading/wavelength-hopping code for each channel and generates a decoded OCDM reception signal.

Abstract: An optical receiver includes a first substrate including a demultiplexer and a first optical waveguide array. An input of the demultiplexer is configured to receive a wavelength division multiplexed optical input signal having a plurality of channels. Each of the plurality of channels corresponds to one of a plurality of wavelengths. Each of the plurality of outputs is configured to supply a corresponding one of the plurality of channels. The first optical waveguide array has a plurality of inputs. Each of the inputs of the first optical waveguide array is configured to receive a corresponding one of the plurality of channels. A second substrate is in signal communication with the first substrate and includes an optical detector array. The optical detector array has a plurality of inputs, each of which is configured to receive a corresponding one of the plurality of channels and generate an electrical signal in response thereto.

Abstract: A method and system for ensuring confidentiality of signal transmission in a point-to-multi point data transmission network like Ether net passive optical network, including at least one hub, at least one transmission medium and at least one station connected to the hub via the transmission medium. When an upstream signal is transmitted from a first station, the upstream signal is reflected by at least one disturbing reflector for producing a disturbing reflection. The disturbing reflection combines with a second reflection of the upstream signal and renders the second reflection undependable by a second station.

Abstract: A system and method is disclosed that parses WDM subnetworks and collects TL1 Performance Monitoring (PM) parameter data from subnetwork network elements (NEs) and applies a set of comparisons to discover under-performing equipment according to predetermined operating thresholds. The comparisons examine NE pump laser baseline values, deviations, efficiency, tilt error, span loss and calculated expected optical power.

Abstract: A space-time division multiple-access (STDMA) laser communications (lasercom) system and related techniques. The STDMA system includes a plurality of remote nodes and an STDMA access node which uses precise electronic beam steering and beacons to provide access to each of a plurality of remote access nodes by means of both space and time-division multiple access.

Abstract: A method for generating transparent pipes for heterogeneous service transmission via OFDMA-PON. In an exemplary embodiment, dedicated sub-channels, which are composed of one or more subcarriers—are used as a “transparent pipe” for delivery of arbitrary analog or digital signals for both circuit switched and packet switched systems.

Abstract: A variety of adaptable electronic duobinary generating filters to be used in communication systems are provided, each filter generating an adaptable electronic duobinay signal which is optimized for system impairments. According to one exemplary implementation, an adaptable electronic duobinary generating filter comprises an adaptable delay-and-add circuit, having an adaptable electronic delay element having a delay ?T: 1/T being the bit rate of the binary data input into the adaptable delay-and-add circuit, and a being an adaptation parameter which can be optimized depending on the system impairments. In one optional implementation, the adaptable electronic delay element can be programmably adaptable to optimize against deterministic system impairments. In another optional implementation, the adaptable electronic delay element can be dynamically adaptable to optimize against dynamically varying system impairments.

Abstract: The disclosed system and method data increases data transmission speed through a memory system by using optical signals comprising a plurality of wavelengths of light so that each pulse of optical signals can represent more than a single bit of data. An optical transmitter comprises multiple, separately controllable light-emitting sections which generate light at different wavelengths. A photoreceptor, comprising sections of materials responsive to light received at different wavelengths, provides an output signal corresponding to the light signals received at the different wavelengths. The photoreceptor therefore can decode the received optical signals into a multiple bit output sequence corresponding with the multiple bit sequence originally transmitted.

Abstract: A data transmission method and apparatus is disclosed by which bidirectional transmission of a plurality of optical signals obtained by conversion of a plurality of serial digital data can be achieved efficiently using a single common optical signal transmission cable. A plurality of serial data based on digital video signals from a camera section are converted into a plurality of optical signals using a CWDM technique and then multiplexed into a multiplexed optical signal. The multiplexed optical signal is signaled to a signal transmission cable through a bidirectional WDM coupler disposed at a first end of the optical signal transmission cable so as to be transmitted from the first end to a second end of the optical signal transmission cable.

Abstract: A passive optical network (PON) device, system and method include an optical line terminal (OLT) receiver configured to receive multiple signals at different wavelengths simultaneously and enable multiple transmitters to operate at the same time during one upstream time slot. The optical line terminal employs Orthogonal Frequency Division Multiple Access (OFDMA) to transparently support a plurality of applications and enable dynamic bandwidth allocation among these applications where the bandwidth is allocated in two dimensional frequency and time space.

Abstract: A multiplexing optical system includes collimator lenses, a first condensing lens, a second condensing lens and an optical fiber. The collimator lenses collimate divergent laser beams that have been emitted from semiconductor lasers. The first condensing lens condenses laser beams transmitted through the collimator lenses in only one of a plane including the stripe width direction of the semiconductor lasers and a plane including a direction perpendicular to the stripe width direction. The second condensing lens condenses laser beams transmitted through the first condensing lens. The optical fiber is arranged in such a manner that the condensed laser beams enter the optical fiber. In the multiplexing optical system, an anamorphic lens is used as the second condensing lens, and the anamorphic lens condenses the laser beams in the two planes in cooperation with the first condensing lens.

Abstract: A method for transmitting a packet in a wireless access network based on a wavelength identification code scheme. The method comprises the steps of connecting n number of RNCs (Radio Network Controllers) to one sub-ring where the “n” is a positive integer, and assigning a unique wavelength to each RNC; identifying a packet to be transmitted between the RNCs located within a same sub-ring using the assigned unique wavelength, and transmitting the packet through an SRC (Sub-Ring Controller); connecting m number of SRCs to one main-ring where the “m” is a positive integer, and assigning a unique wavelength to each SRC; and detaching a wavelength identification code from the packet to be transmitted between the RNCs located within different sub-rings, and transmitting the packet having the encapsulated wavelength identification code through an MRC (Main-Ring Controller).

Abstract: An optical spread spectrum communication system includes a tunable laser which sequentially outputs optical signals having different wavelengths. The laser produces a frequency spectrum having a plurality of closely spaced modes relative to optical frequencies. The system further includes an optical modulator and a frequency synthesizer. The frequency synthesizer controls the optical modulator to allow specific modes from the frequency spectrum to pass through. Additionally, the system includes a tunable filter and a phase locked loop (PLL) control circuit. The PLL control circuit controls the filter to select specific channels. The selection of the specific modes by the modulator and the selection of channels by the tunable filter are performed independent of each other and are based on randomly assigned codes generated in accordance with one or more algorithms.

Abstract: The present invention provides an optical wavelength-division multiple access system and a corresponding optical network unit. A wavelength band Da (wavelengths ?d1 to ?dn) for downlink optical signals corresponding to the n ONUs, a wavelength band Ua (wavelengths ?u1 to ?un) for uplink optical signals corresponding to the n ONUs, a wavelength band Db (wavelengths ?dn+1 to ?dn+m) for downlink optical signals corresponding to the m ONUs, and a wavelength band Ub (wavelengths ?un+1 to ?un+m) for uplink optical signals corresponding to the m ONUs are set different from one another, the wavelength bands Ua and Ub are set adjacent to each other, and the wavelength bands Ua and Da or the wavelength bands Ub and Db are set adjacent to each other.

Abstract: A passive optical network which employs multiple wavelengths to increase overall system bandwidth, with each wavelength being shared by multiple optical network units (ONUs) according to a time division multiple access (TDMA) protocol. The upstream TDMA traffic therefore includes multiple TDMA data streams at different wavelengths. An optical line terminal (OLT) preferably receives the multiple TDMA data streams and separates them to different detectors before ultimately combining all data into a single data stream using a multiplexer after performing clock and data recovery functions. In this manner, the upstream bandwidth in a passive optical network can be markedly increased without requiring an increase in data transmit speeds, and while using low cost/low speed detectors in the OLT, and low cost/low speed transceivers in the ONUs. System bandwidth can be further improved by using higher cost, higher speed components.

Abstract: A method of optical communication having improved security is described. The data content of an initially provided data signal is apportioned among two or more distinct optical wavelength channels. A transmitted signal spans these two or more channels. A respective portion of the data content of the transmitted signal is allocated to each of the optical wavelength channels. In certain embodiments of the invention, each such portion comprises data placed in the pertinent wavelength channel during assigned time windows.

Abstract: In an optical grating device, a grating arrangement receives different wavelength output signals from a plurality of radiation sources at input ports thereof, and generates therefrom a multiplexed wavelength output signal at a zero diffraction order output port of the grating arrangement. Additionally, the gating arrangement generates at least one predetermined wavelength output signal at one of a group consisting of a separate predetermined location in an at least one of a symmetric non-zero diffraction order of the grating arrangement, within the grating arrangement itself, and a combination thereof. A separate power tap is coupled to detect the power of a separate one of the at least one predetermined wavelength output signal from the grating arrangement.

Abstract: A high-speed optical network includes according to the invention a housing having a plurality of slots for accommodating a number of line cards and an optional backplane facilitating communication between the line cards. The line cards include a client communication interface and a DWDM communication interface, for example, gigabit Ethernet interface, SONET interface or DWDM interface. Advantages of the invention include a high-speed network and network components that are capable of performing at a level consistent with optical network systems and which efficiently supports DWDM in a space-effective and cost-effective manner.

Abstract: A system and method for monitoring all the characteristic parameters of a DWDM communication system is implemented with two variants. Firstly, this is achieved by means of a specific grating spectrometer displaying a high resolution and a high-speed sampling of the measured values, and secondly by the application of an opto-electronic cross correlator as a purely electronic solution. The grating spectrometer is expediently a particular system in a mixed array according to Ebert and Fastie, wherein the light to be measured passes four times through the grating in a specific manner. The opto-electronic cross correlator can mix the working light with a reference light tunable in terms of its frequency to form an electrical low-frequency signal that is analyzed in a high-impedance operation.

Abstract: The access node for optical networks with variable access wavelengths can be connected to user devices via respective first optical conductors and can be connected to the optical network via second optical conductors. The novel access node has light sources which emit at the wavelengths defined in the optical network. The light of the light sources can be modulated in the user devices. This prevents that in each case a light source which must be able to emit light of a different wavelength in a dynamic optical network or the wavelengths of which must be subsequently converted must be arranged in the individual user devices. In addition, it also prevents circuit boards leading to a high logistical expenditure having to be provided in the user devices. Accordingly, according to the invention, it is possible to construct the individual user devices without light sources. This considerably simplifies their construction and the method of use.

Abstract: The present invention relates to a spectrometer module comprising an input, for receiving an incoming optical signal, a variable differential group delay (DGD) element, for applying a variable birefringence retardation to said incoming optical signal, and a detector unit for detecting the power of a signal exiting said variable DGD element, having a defined state of polarization. It also relates to a monitor module, a monitoring unit and a monitoring system, comprising such a spectrometer module for use in monitoring an optical network. Further, the invention relates to a spectrometer device, for spectrometry purposes, comprising a spectrometer module as stated above.