Showing papers by "Finisar published in 2007"

Electronic modules having integrated lever-activated latching mechanisms

Abstract: An integrated latching mechanism for use with a user pluggable electronic module, such as an opto-electronic transceiver module, is disclosed. The latching mechanism allows the user to selectively latch the module within a corresponding host port by manipulation of a pivot lever. Movement of the pivot lever causes a locking pin to extend and latch the module within the port. Conversely, movement of the pivot lever can disengage the locking pin and thereby allow the user to extract the module from within the port. The pivot lever can further include a biasing member that biases the pivot lever in a locked position.

Communications module edge connector having multiple communication interface pads

Abstract: An edge connector design for use with a printed circuit board included in a communications module is disclosed. In one embodiment, the edge connector comprises a planar surface defining a terminal end of the printed circuit board, and a plurality of conductive contact pads arranged on the planar surface. The contact pads include first and second ground contact pads disposed adjacent opposite side portions of the planar surface and first and second power contact pads disposed proximate a central portion of the planar surface. First and second pairs of differential transmit data signal contact pads, as well as first and second pairs of differential receive data signal contact pads are also included, the pairs being disposed between one of the ground contact pads and one of the power contact pads. The edge connector is received by a female connector of a host device to connect the module to the host.

Optical transmission using semiconductor optical amplifier (soa)

Abstract: A fiber optic communication system containing a binary first signal with an amplitude modulated component and a binary second signal with amplitude and frequency modulated components, in which the second signal is characterized in that the 1 bits are red shifted The system further contains a semiconductor optical amplifier adapted to receive the binary second signal that operates in saturation, and an optical spectrum reshaper adapted to reshape the amplified signal into a binary fourth signal, wherein the binary fourth signal has an amplitude modulated component and a frequency modulated component

Optical transmitter having a widely tunable directly modulated laser and periodic optical spectrum reshaping element

Abstract: An optical transmitter is disclosed including a widely tunable laser coupled to a periodic optical spectrum reshaper (OSR) to convert frequency modulated pulses from the laser into amplitude modulated pulses. The laser is tuned to generate pulses corresponding to passbands of the OSR spanning a wide range of frequencies. The laser includes a gain section having an optical path length substantially shorter than the total optical path length of the laser. The laser may be a Y-branch laser having reverse-biased sampled gratings or ring resonator filters tuned by stripe heaters. The laser may also include a reflective external cavity section tunable by modulating the temperature of ring resonators or etalons. The OSR may be integrally formed with the external cavity of the ECL laser.

Serializer/deserializers for use in optoelectronic devices

Abstract: An optoelectronic device implements a serializer array circuit or multi-channel CDR circuit to reduce the cost and size of the circuit. An efficient serializer array circuit includes a plurality of serializer blocks sharing the functionality of a single CMU to clock a plurality of serial signals out of the final stages of the serializer blocks. An efficient multi-channel CDR circuit includes a single CDR for acquiring the clock for one of a plurality of data signals and a plurality of DLLs using the recovered clock to acquire the data for the plurality of data signals. Alternately, an efficient multi-channel CDR circuit includes a single frequency acquisition loop and a plurality of data acquisition loops.

100GbE- Optical LAN Technologies [Applications & Practice]

Abstract: This article discusses optical and IC technologies feasible for use in the development of LAN interfaces based on future IEEE 100-gigabit Ethernet SMF and MMF standards. SMF approaches using 10-Gb/s and 25-Gb/s WDM, and DWDM WAN technologies are outlined, with the 25-Gb/s approach examined in detail. The MMF approach using 10-Gb/s parallel optics technology is also examined in detail. Future technologies required for high-volume, low-cost 100 Gb/s are previewed.

Connector structure for a transceiver module

Abstract: A transceiver module, such as a copper transceiver module, that utilizes an example connector structure for receiving the plug of a communication cable. The example connector structure is configured to house a plurality of electronic components in such a way as to efficiently utilize the space within the connector structure itself In one example embodiment, a connector structure for use in a copper transceiver module includes a body, a first plurality of conductive elements attached to the body, and first and second cavities defined in the body. The first plurality of conductive elements is configured to electrically connect with a corresponding second plurality of electrical elements on a plug of a communications cable. A first plurality of electrical cores and a printed circuit board are positioned in the first cavity. A second plurality of electrical cores is positioned in the second cavity.

Optical component and transceiver packaging

Abstract: Methods of packaging a high density optical module. In one example embodiment, a method of packaging the high density optical module includes various acts. First, a first detachable fiber assembly is connected to an optical component disposed in the module such that the connection between the fiber assembly and the optical component is disposed inside a housing of the optical module. Next, the fiber included in the fiber assembly is spooled around a spooling assembly. Then, the receptacle is secured in a receptacle holder such that the receptacle is able to connect with an external fiber connector. Next, the fiber assembly is detached from the optical component. Finally, the optical component is heated such that a ball grid array connection, that connects the optical component to a high speed printed circuit board, flows such that the optical component can be removed from the high speed printed circuit board.

Chirp-managed, electroabsorption-modulated laser

Abstract: An optical transmitter comprising: an optical source modulated with an input digital data signal so as to generate a first, frequency-modulated digital signal; and an amplitude modulator, modulated with the logical inverse of the input digital data signal, for receiving the first, frequency-modulated signal and generating a second, amplitude-modulated and frequency-modulated digital signal; wherein the optical source and the amplitude modulator are each configured so as to produce positive transient chirp. A method for transmitting a signal, the method comprising: generating a first, frequency-modulated digital signal by modulating an optical source with an input digital data signal; and providing a second, amplitude-modulated and frequency-modulated digital signal by passing the first, frequency-modulated digital signal through an amplitude modulator while modulating the amplitude modulator with the logical inverse of the input digital data signal; wherein the optical source and the amplitude modulator are each configured so as to produce positive transient chirp.

Latching mechanism for a module

Abstract: A latching mechanism for use in selectively securing a module within a receptacle of a host device. In one example embodiment, a latching mechanism includes a bail and a latch attached to the bail. The bail is configured to be attached to a shell of a module and to rotate about a first axis between a latched position and an unlatched position. The first axis is in a fixed position relative to the shell. The latch is attached to the bail at a second axis that is offset from the first axis. The latch is configured to rotate about the second axis. The second axis is movable relative to the shell.

Displaying eye-diagram and digital diagnostic data using network analyzers

Abstract: Methods and apparatuses for displaying information for analyzing a signal transmitted in a communication system. The method can include displaying digital diagnostic data received from a monitoring interface of a transceiver. An eye-diagram for the signal is also displayed. The digital diagnostic data, network protocol analysis results, and/or the eye-diagram can be selectively displayed using a combined unit or stand alone units. Additionally, results of network protocol analysis can also be displayed with the digital diagnostic data and eye diagram.

Alternate storage of repeated data within a data storage device

Abstract: A data storage device having capabilities for alternate storage of repeated data and methods for alternate storage of repeated data within a data storage device. In one example embodiment, a method is disclosed for a data storage device to alternately store data within the data storage device. First, the data storage device identifies a data pattern that is present at a plurality of physical addresses on the data storage device. Next, the data storage device writes the data pattern to a single physical address. Then, the data storage device remaps the logical address of each of the plurality of physical addresses to the single physical address. Finally, the data storage device allocates a new logical address for each of the plurality of physical addresses. In this example method, the identifying, writing, remapping, and allocating are performed by the data storage device without regard to data file boundaries.

High-temperature operation of vertical cavity surface emitting lasers

Abstract: Embodiments of the present invention provide a system for increasing an operational life of a VCSEL. The system can include control circuitry for reducing an amount of bias current at high temperatures and increasing a power of the laser at low temperatures. This control circuitry can further include at least one of a temperature sensor, a Field Programmable Gate Array, a read only memory module, and an electrically erasable programmable read only memory module (EEPROM). In alternate embodiments, the control circuitry can further include a lookup table that sets the bias current depending on a temperature of the laser. The laser can be part of an optoelectronic transceiver module which can include, by way of example and not limitation, SFP, XFP, X2, XAUI, XENPAK, XPAK, GBIC, 8G, 16G, and other optoelectronic modules.

Transceivers for testing networks and adapting to device changes

Abstract: Test transceivers are disclosed for testing optical networks. The test transceivers generate one or more errors on a network in a specific, reproducible way, thereby enabling a tester to easily and readily identify whether network devices are operating properly, or prone to failure. A corrective transceiver is also disclosed. The corrective transceiver is configured to continually detect operating parameters of one or more network devices in a network. The corrective transceiver can identify the operating parameters through out-of-band communication with the one or more network devices. The corrective transceiver is further configured with one or more instructions to adjust its own operating parameters to re-sync with another network device as necessary to continue network communications during a failure of the network device.

Optical transceiver module having an active linear optoelectronic device

Abstract: An optoelectronic transceiver comprises an active linear TOSA circuit mounted on a header. The active linear TOSA circuit includes input nodes for receiving a differential signal pair, a first bipolar transistor, a second bipolar transistor and an electro-optical transducer. A base terminal of the first bipolar transistor is coupled to the two input nodes and an emitter terminal of the first bipolar transistor is coupled to a base terminal of the second bipolar transistor. A collector terminal of the first bipolar transistor is coupled to a first terminal of the electro-optical transducer, the first terminal of the electro-optical transducer also being configured to be coupled to a voltage source. A collector terminal of the second bipolar transistor is coupled to a second terminal of the electro-optical transducer and an emitter terminal of the second bipolar transistor is coupled to a signal ground which is not the header ground.

Traffic generator program

Abstract: Systems and methods for a traffic generator for use in a network. A computer program product such as a plug in for a browser captures data that is sent over a network. The plug in does not need to understand or capture keyboard or mouse input. Rather, the plug in captures low level network data that is generated in response to high level user input. The captured data can be used to reflect real network usage during the testing of networks and network equipment. The traffic can also be modified to reflect multiple virtual users and test the network or network equipment accordingly.

Electromagnetic interference containment in a transceiver module

Abstract: A transceiver module that utilizes an electromagnetic interference (EMI) containment structure for dealing with electromagnetic interference generated within the transceiver module. In one example embodiment, a transceiver module includes a housing, a printed circuit board disposed within the housing, and an EMI shield disposed about the printed circuit board. In this example embodiment, the printed circuit board includes electronic circuitry and a plurality of differential signal lines. Further, the EMI shield includes a body having a slot, a plurality of fingers on at least one edge of the body, and tabs that are operative to connect the body to the printed circuit board. The slot of the EMI shield receives the printed circuit board such that the differential signal lines of the printed circuit board pass through the slot. The fingers of the EMI shield enable the body to maintain a biased contact with the housing.

Discrete bootstrapping in an optical receiver to prevent signal feedback

Abstract: An optical receiver assembly that is configured to avoid the introduction of feedback in an electrical signal converted by the assembly is disclosed. In one embodiment, an optical receiver assembly is disclosed, comprising a capacitor, an optical detector provided with a power supply being mounted on a top electrode of the capacitor, and an amplifier mounted on the reference surface. The assembly further includes an isolator interposed between the reference surface and the capacitor, wherein the isolator includes a bottom layer of dielectric material that is affixed to a portion of the reference surface, and a metallic top plate that is electrically coupled both to a ground of the amplifier and to the capacitor. This configuration bootstraps the amplifier ground to the amplifier input via the photodiode top electrode of the capacitor to cancel out feedback signals present at the amplifier ground.

Protecting against counterfeit electronics devices

Abstract: An optical transceiver module is authenticated in a host system. A host generates a data string and writes the data string to a first predetermined memory location known to the transceiver. The data string is cryptographically altered (either encrypted or decrypted) by the transceiver and written to a second predetermined memory location known to the host. The host retrieves the cryptographically altered data string and performs a complementary cryptographic operation (either a decryption or encryption, respectively) thereon, creating a resulting data string. If the resulting data string is equal to the data string written to the first predetermined memory location, the transceiver is authenticated. The host and the transceiver may switch roles, with the transceiver generating the data string, the host cryptographically altering it, and so on. The host encrypts data strings when the transceiver decrypts data strings, and vice versa.

Self-testing optical transceiver

Abstract: Systems and methods for an optical transceiver module to perform one or more diagnostic self-tests without the assistance of a host computing system. The optical transceiver module includes at least one processor, a persistent memory and a system memory. The persistent memory, which is coupled to the at least one processor, contains microcode. The microcode is loaded from the persistent memory to the system memory and executed by the at least one processor. The executed microcode causes the optical transceiver module to perform one or more diagnostic self-tests. The diagnostic result data of the one or more diagnostic self-tests is then stored in the persistent memory and is formatted for analysis. The formatted data may then be analyzed to ascertain the response of the optical transceiver to changes in its test environment.

Receive only physical interface device IC used in a passive network tap

Abstract: A receive or listen only Physical Interface Device (Phy). The receive or listen only Phy is configured to have a front end configured to only receive data from a communications network. The receive only Phy may be implemented a part of a tap device including a first network port for receiving a first network signal having a first format; a receive only Phy for converting the first network signal into a second signal format; and a transmit and receive Phy for receiving the first network signal in the second signal format and converting it into the first signal format.

Optical connector latch assembly for an optoelectronic module

Abstract: An optical connector latch assembly for an optoelectronic module that can releasably engage an optical fiber connector that is received in a receptacle of the optoelectronic module. In one example embodiment, an optical connector latch arm includes a base, a shaft extending from the base, and a hook extending from the shaft. In this example embodiment, the base defines a complementary structure that is configured to engage a complementary structure of an OSA connector block. Also, the hook is configured to releasably engage an optical fiber connector.

Network diagnostic systems and methods for aggregated links

Abstract: A networking system is provided. The networking system may include a diagnostic module. The diagnostic module may include one or more statistics modules. The diagnostic module may include a routing module configured to route messages to the statistics modules. The messages may be derived from network messages from an aggregated link.

Versatile compact transmitter for generation of advanced modulation formats

Abstract: A system for generating a return-to-zero differentially-phase-shift-keyed (RZ-DPSK) optical signal comprising: a driver comprising an N-level digital multilevel transformer (N-level digital transformer) configured to receive a two level digital electrical signal representing 1s and Os and output a N-level electrical signal, wherein N > 2; an FM source configured to receive the N-level electrical signal output by the driver and generate an optical frequency modulated signal (FM/AM source); and an optical spectrum reshaper (OSR) configured to receive the optical frequency modulated signal output by the FM source and generate the desired RZ-DPSK optical signal. A method for generating a retum-to-zero differentially-phase-shift-keyed (RZ-DPSK) optical signal, the method comprising: (1) receiving a two level digital electrical signal representing 1s and Os and outputting a N-level electrical signal, wherein N > 2; (2) receiving the N-level electrical signal output and generating an optical frequency modulated signal; and (3) receiving the optical frequency modulated signal and generating the desired RZ-DPSK optical signal.

Identifying and resolving problems in wireless device configurations

Abstract: Systems and methods for identifying and resolving problems in wireless device configurations in a wireless network. In one example embodiment, a method for resolving wireless device configuration problems includes various acts including identifying all wireless devices that are wired to a network, retrieving configuration information from each wireless device, retrieving wireless device incompatibility information and corresponding configuration solutions for each wireless device, attempting to contact each wireless device over one or more wireless communication channels in order to determine if one or more wireless capabilities of each wireless device are functioning properly, and determining that the incompatibility information of one of the wireless devices with a malfunctioning wireless capability conflicts with the configuration information of one or more of the wireless devices.

Electromagnetic radiation containment and heat management in an electronic module

Abstract: In one example, and electromagnetic radiation containment system includes an electrically conductive shroud configured to be mounted to a ground plane of a host board, the electrically conductive shroud defining an opening by way of which an edge connector of an electronic module can be received, the electrically conductive shroud sized and configured to substantially enclose a host board connector mounted to the host board. The electromagnetic radiation containment system further includes, in this example, an electrically conductive sealing element configured to be disposed about a portion of the electronic module such that when the edge connector of the electronic module is fully received in the host board connector, the electrically conductive sealing element cooperating with the electrically conductive shroud to at least partially define a Faraday cage substantially enclosing the edge connector and the host board connector.

Chirp Managed Laser (CML) transmitter

Abstract: A fiber optic communication system comprising: an optical signal source adapted to receive a binary base signal having a bit period T, and generate a first signal, wherein the first signal is frequency modulated; and an optical spectrum reshaper (OSR) adapted to reshape the first signal into a second signal, wherein the second signal is amplitude modulated and frequency modulated; characterized in that: the frequency excursion of the first signal is adjusted such that the frequency excursion is substantially equal to the ratio of the bit period of the digital base signal to total dispersion of the transmission fiber, whereby to increase the tolerance of the second signal to dispersion in a transmission fiber.

Passive Network Tap With Bidirectional Coupler and Associated Splitting Methods

Abstract: The principles of the present invention relate to passive full-duplex bidirectional Zero Packet Loss (ZPL) network taps that include single, dual, or dual differential couplers that are placed in the communication path between two network devices that communicate using a full-duplex bidirectional data stream that include a first and a second data component. The bidirectional couplers are configured to at least partially obtain a second data stream that includes at least the first data component and to obtain a third data stream that includes at least the second data component. In some embodiments, the bidirectional couplers may include a signal separation module or stage that is configured to further separate the first and second data components.

EMI reduction stage in a post-amplifier

Abstract: An amplifier output stage for reducing Electromagnetic Interference (EMI) that includes an output node and an input node. A first transistor has a base terminal coupled to the input node and has a collector terminal coupled to the output node. A second transistor has a base terminal coupled to an emitter terminal of the first transistor and has a collector terminal coupled to the output node. A third transistor has a collector terminal coupled to the emitter terminal of the first transistor and the base of the second transistor and has an emitter terminal coupled to a current source and to an emitter terminal of the second transistor. A resistor has a first terminal coupled to a base terminal of the third transistor and has a second terminal coupled to the emitter terminal of the first transistor.

Method of analyzing network with generated traffic

Abstract: Generating traffic in a network environment. A traffic generator can be used to record the low level network data that is generated in response to high level user input. The low level network data can be processed to simulate multiple virtual users. Once the network data is processed, the virtual data can be sent over a network as if multiple users were using the network. The response and functionality of the network and of network components can then be monitored and evaluated based on the response to the virtual data.