Abstract: A data transmission system that detects fiber faults receives a plurality of data packets carried on a plurality of Gigabit Ethernet links at a plurality of Gigabit Ethernet input/output ports. The system then multiplexes, on a bit by bit basis, the data packets onto an optical link. When the system detects a loss of signal in one of the Gigabit Ethernet links, a signal loss code insert is generated. The system then multiplexes the signal loss code insert with the data packets.

Abstract: A method of data communication that includes receiving a plurality of 8b/10b encoded data streams. The method also includes multiplexing, on a word by word basis, each of the plurality of data streams and forming a new encoded data stream. The method also includes generating an interleaved encoded data stream substantially similar to an 8b/10b encoded spectrum from the new encoded data stream.

Abstract: A synchronization circuit including a plurality of samplers, the plurality of samplers sampling an input signal with a plurality of respective clock signals and producing a plurality of respective sampled output signals. The synchronization circuit also includes at least one phase detector coupled to the plurality of samplers, the at least one phase detector determining whether the plurality of sampled output signals are different and producing at least one control signal, the at least one control signal indicating whether the plurality of sampled output signals are different. In addition, the synchronization circuit includes a delay adjuster coupled to the at least one phase detector, the delay adjuster adjusting a delay of the input signal according to the at least one control signal output by the at least one phase detector.

Abstract: A system for data communication receives more than one input data streams that have independent clocks and an input order. The system synchronizes the input data streams to a common clock, and multiplexes the synchronized data streams onto an input of a data communication link. The system demultiplexes one or more output data streams from an output of the data communication link. The system identifies each of the output data streams and reorders the output data streams into the same order as the input data streams.

Abstract: A system for data transmission and communication receives a plurality of Gigabit Ethernet data packets from multiple Gigabit Ethernet links. The system bit multiplexes the data packets, on a bit by bit basis, together onto a fiber optic link. At the output of the fiber optic link, the bits are demultiplexed into data packets and transmitted onto multiple Gigabit Ethernet links. The high speed fiber optic link transmits the data at higher speed than is possible over each individual Gigabit Ethernet link.

Abstract: An integrated optoelectronic circuit chip for optical data communication systems includes a silicon substrate, at least one MOS field effect transistor (MOSFET) formed on a portion of the silicon substrate, and an avalanche photodetector operatively responsive to an incident optical signal and formed on another portion of the substrate. The avalanche photodetector includes a light absorbing region extending from a top surface of the silicon substrate to a depth h and doped to a first conductivity type. The light absorbing region is ionizable by the incident optical signal to form freed charge carriers in the light absorbing region. A light responsive region is formed in the light absorbing region and extends from the top surface of the silicon substrate to a depth of less than h. The light responsive region is doped to a second conductivity type of opposite polarity to the first conductivity type.

Abstract: An integrated optoelectronic circuit chip for optical data communication systems includes a silicon substrate, at least one MOS field effect transistor (MOSFET) formed on a portion of the silicon substrate, and an avalanche photodetector operatively responsive to an incident optical signal and formed on another portion of the substrate. The avalanche photodetector includes a light absorbing region extending from a top surface of the silicon substrate to a depth h and doped to a first conductivity type. The light absorbing region is ionizable by the incident optical signal to form freed charge carriers in the light absorbing region. A light responsive region is formed in the light absorbing region and extends from the top surface of the silicon substrate to a depth of less than h. The light responsive region is doped to a second conductivity type of opposite polarity to the first conductivity type.

Abstract: An integrated optoelectronic circuit chip for optical data communication systems includes a silicon substrate, at least one MOS field effect transistor (MOSFET) formed on a portion of the silicon substrate, and an avalanche photodetector operatively responsive to an incident optical signal and formed on another portion of the substrate. The avalanche photodetector includes a light absorbing region extending from a top surface of the silicon substrate to a depth h and doped to a first conductivity type. The light absorbing region is ionizable by the incident optical signal to form freed charge carriers in the light absorbing region. A light responsive region is formed in the light absorbing region and extends from the top surface of the silicon substrate to a depth of less than h. The light responsive region is doped to a second conductivity type of opposite polarity to the first conductivity type.

Abstract: A method for use in a data transmission system comprises the steps of: (i) adding timing information to a serial data stream; (ii) recovering the timing information from the serial data stream to generate a plurality of clock signals associated with the timing information, each clock signal having a common frequency and a different phase associated therewith, the common frequency being less than a frequency associated with the serial data stream; and (iii) converting the serial data stream to a plurality of parallel data streams respectively using the plurality of clock signals. The timing information may be added to the serial data stream at a data transmitter portion of the system. The invention provides for various ways to add the timing information to the serial data stream, i.e., enrich the serial data stream with the timing information. This timing information is preferably phase locked to the data and has a frequency less than the serial data transmission rate.

Abstract: An optical demultiplexer demultiplexes an N channel multiplexed optical data signal, at a first data rate, into N signal data channels. The demultiplexing is provided by N optical receivers, each receiver receiving a clock signal and the multiplexed optical data signal which is demultiplexed into a different one of the N signal data channels. In another embodiment, a shared photodetector converts the received multiplexed optical data signal into a multiplexed data signal which is then used by all of the N receivers.

Abstract: A differential optical signal receiver includes an interference-rejecting circuit to provide enhanced interference signal rejection. The differential optical signal receiver includes a differential optical signal detector for detecting a received differential optical signal and converting it to a differential electrical signal. An interference-rejecting differential electrical circuit, including a common source load, processes the differential electrical signal so as to reject any electrical interference signal other than said differential electrical signal.

Abstract: Automatic bias setting circuits for multiple quantum well (MQW) diodes and optical modulators generally are described. Both digital and analog circuits are provided and techniques for utilizing such circuits for monitoring and controlling optical modulator signal quality are disclosed. In one approach, a desired modulation voltage range is determined. A bias voltage is stepped from a first predetermined voltage up to a second predetermined voltage. A maximum differential photocurrent is determined and the bias voltage corresponding to that photocurrent is then employed so that optimal optical modulator signal quality is achieved. An advantageous application of this technique is in wavelength division multiplexed (WDM) systems in which different optical modulators are operating at different wavelengths. In such a system, a different voltage bias will typically be determined for each optical modulator.

Abstract: An optical fiber compatible modulator device provides high-contrast levels switchable using modest applied voltages. As a two-port optical modulator, a normal light signal incident at a first port is deflected to a non-normal direction for passage through an absorption layer (e.g., a multiple-quantum well (MQW) layer), the absorption layer having an adsorption characteristic which changes as a function of a voltage applied across it. The non-normal direction light signal exiting the absorption layer is deflected to a normal light signal for output from a second port of the optical modulator. As a one-port optical modulator, a normal light signal received at a first port is deflected to a non-normal direction for passage through an absorption layer. A reflector reflects a non-normal direction light signal exiting the layer back through the layer to the deflector means and is output at the port of the optical modulator.

Abstract: A feedback element for a two beam smart pixel receiver having at least one pair of electron devices of opposite electrical conductivity type, such as an NFET and a PFET, with input electrodes electrically connected and output electrodes electrically connected. The devices of a pair have opposing differential resistance characteristics in response to the same input signal so that the resistances of the devices of the pair add to become more linear.