Abstract: An embodiment of the invention includes a high speed feed thru connecting a first circuit outside a housing to a second circuit inside the housing. The first circuit includes a first high speed integrated circuit chip and the second circuit includes a second high speed integrated circuit chip or optoelectronic device. The high speed feed thru includes an inside coplanar structure positioned at least partially inside the housing, the inside coplanar structure connected to the second circuit. The high speed feed thru also includes an outside coplanar structure positioned at least partially outside the housing, the outside coplanar structure connected to the first circuit. A material separates the inside coplanar structure and the outside coplanar structure. At least one guided via extends through the material, connecting the inside coplanar structure and the outside coplanar structure.

Abstract: Thermal chirp compensation in a chirp managed laser. In one example embodiment, a method for thermal chirp compensation in a chirp managed laser (CML) includes several acts. First, a first bias condition and temperature is selected. Next, a first thermal chirp compensation signal is generated. Then, the laser is driven by biasing a first input drive signal with the first thermal chirp compensation signal. Next, a second bias condition and temperature is selected. Then, a second thermal chirp compensation signal is generated. Finally, the laser is driven by biasing a second input drive signal with the second thermal chirp compensation signal.

Abstract: In one example embodiment, a high-speed package includes first and second layers and a multi-channel non-coplanar interconnect. The first layer includes first and second sets of coplanar transmission lines. The second layer includes third and fourth sets of coplanar transmission lines. The multi-channel non-coplanar interconnect includes first and second channels. The first channel connects the first set of transmission lines to the third set of transmission lines. The second channel connects the second set of transmission lines to the fourth set of transmission lines.

Abstract: An embodiment of the invention includes a high speed feed thru connecting a first circuit outside a housing to a second circuit inside the housing. The first circuit includes a first high speed integrated circuit chip and the second circuit includes a second high speed integrated circuit chip or optoelectronic device. The high speed feed thru includes an inside coplanar structure positioned at least partially inside the housing, the inside coplanar structure connected to the second circuit. The high speed feed thru also includes an outside coplanar structure positioned at least partially outside the housing, the outside coplanar structure connected to the first circuit. A material separates the inside coplanar structure and the outside coplanar structure. At least one guided via extends through the material, connecting the inside coplanar structure and the outside coplanar structure.

Abstract: In one example, a hybrid surface mountable package includes a housing at least partially defining a sealed cavity, two microwave integrated circuits (MIC) chips positioned inside the sealed cavity, and a very-high-speed interconnect connecting the two MIC chips to each other. The very-high-speed interconnect includes strong coupling co-planar waveguide (CPWG) transmission lines.

Abstract: In one example embodiment, a high-speed package includes first and second layers and a multi-channel non-coplanar interconnect. The first layer includes first and second sets of coplanar transmission lines. The second layer includes third and fourth sets of coplanar transmission lines. The multi-channel non-coplanar interconnect includes first and second channels. The first channel connects the first set of transmission lines to the third set of transmission lines. The second channel connects the second set of transmission lines to the fourth set of transmission lines.

Abstract: An optical transmitter comprising: (i) an electrical switch; (ii) a laser array comprising a plurality of tunable laser elements; and (iii) an Optical Spectrum Reshaper (OSR) used to reshape the output pulses from the laser elements in the laser array; wherein the electrical switch takes an input electrical digital signal and selectively directs it to a specific laser element in the DFB laser array.

Abstract: The frequency chirp modulation response of a directly modulated laser is described using a small signal model that depends on slow chirp amplitude s and slow chirp time constant ?s. The small signal model can be used to derive an inverse response for designing slow chirp compensation means. Slow chirp compensation means include electrical compensation, optical compensation, or both. Slow chirp electrical compensation can be implemented with an LR filter or other RF circuit coupled to a direct modulation source (e.g., a laser driver) and the directly modulated laser. Slow chirp optical compensation can be implemented with an optical spectrum reshaper having a rounded top and relatively large slope (e.g., 1.5-3 dB/GHz). The inverse response can be designed to under-compensate, to produce a flat response, or to over-compensate.

Abstract: In one example embodiment, a high-speed transponder includes a printed circuit board having a set of coplanar high-speed traces, and a high-speed circuit and a package mounted to the printed circuit board. The package includes an outside housing and a second high-speed circuit positioned inside the housing. The high-speed transponder also includes a high-speed feed thru which includes an inside coplanar structure positioned inside the housing, a strip line structure positioned through the housing, and an outside coplanar structure positioned outside the housing. The second high-speed circuit is operably coupled to the inside coplanar structure, which is operably coupled to the strip line structure, which is operably coupled to the outside coplanar structure, which is operably coupled to the first high-speed circuit via the set of coplanar high-speed traces. The signal plane of the outside coplanar structure is flipped with respect to a signal plane of the inside coplanar structure.

Abstract: An optical transmitter comprising: (i) an electrical switch; (ii) a laser array comprising a plurality of tunable laser elements; and (iii) an Optical Spectrum Reshaper (OSR) used to reshape the output pulses from the laser elements in the laser array; wherein the electrical switch takes an input electrical digital signal and selectively directs it to a specific laser element in the DFB laser array.

Abstract: A method of generating an authentication for updating a mobile communications device's 40 location to a second communications device 60 is disclosed herein. The mobile communications device 40 is registered to a home network 30 comprising a proxy server but roams to a foreign network 40 with a different network number. The method proposes that, at the time of performing the location update, the second communications device and the proxy server each provides an input to a hash function to generate a shared secret; and using the shared secret as the authentication when the proxy server or the mobile communications device transmits the location update to the second communications device.

Abstract: A method of generating an authentication for updating a mobile communications device's 40 location to a second communications device 60 is disclosed herein. The mobile communications device 40 is registered to a home network 30 comprising a proxy server but roams to a foreign network 40 with a different network number. The method proposes that, at the time of performing the location update, the second communications device and the proxy server each provides an input to a hash function to generate a shared secret; and using the shared secret as the authentication when the proxy server or the mobile communications device transmits the location update to the second communications device.

Abstract: A method of dispersion compensation for an optical network divides the optical fiber transmission line into sections located between a pair of re-configurable nodes. For each section, at either one of the pair of nodes, wavelengths are classified into a first set of added waves, a second set of dropped waves and a third set of express waves. A first predetermined dispersion compensation is provided to the third set of express waves so that the third set of express waves have a second predetermined dispersion. Methods for determining linear and nonlinear impairment parameters so that the optical parameters due to both linear and nonlinear transmission impairments of each section can be independent obtained and disseminated throughout the network.

Abstract: The present invention enables system verification and test of high quality optical networks with extremely low BER. The invention allows investigation of optical nonlinear penalty contributions by varying channel power while keeping constant OSNR at the receiver end. The present invention provides a method to measure system performance gains and penalties associated with different dispersion maps. The present invention gives simple automated test procedures which ensures fast test time. The present invention comprises a transmitter for transmitting an optical test signal to the optical network. The present invention includes a first attenuating module for attenuating channel power of the optical test signal. Also, the present invention includes a noise injection module for adding noise to the optical test signal.

Abstract: A Dense Wavelength Division Multiplexed (DWDM) optical transmission system that compensates for unequal channel performance over an extended fiber transmission distance.

Abstract: A high speed DWDM optical transmission system that reduces a fiber dispersion limit without reducing the total channel count of a multi-wavelength optical signal. The system achieves such reduction in the fiber dispersion limit by employing a multi-wavelength optical signal comprising a gap-free band structure, and performing per-band dispersion compensation on the optical signal by adjusting residual dispersion values associated with one or more of the bands. In one embodiment, the system includes a first dispersion compensation module (DCM) that provides a dispersion-compensated multi-wavelength optical signal containing wavelength-dependent residual dispersion to a band splitter. The band splitter separates the dispersion-compensated optical signal into a plurality of bands such that no band gaps are formed between adjacent bands, and provides each band to a respective second DCM configured to reduce the residual dispersion associated with that band to a predetermined range of residual dispersion values.

Abstract: A wavelength division multiplexed (WDM) optical communications network is configured and operated to enable transmitter output power for a given wavelength channel to be adjusted to achieve a desired optical signal-to-noise ratio (OSNR) for the channel independently of the power levels of other optical signals carried on the same path. Optical amplifiers in the optical links extending between the transmitter and an optical receiver are configured to operate with constant gain over a specified range of input optical signal power, and the links are configured such that the power level of the signal provided to each optical amplifier is within the specified range of input signal power to prevent the deep saturation of the optical amplifiers due to optical amplifier cascading. When a channel is being added or adjusted, the OSNR of the optical communications signal received by the receiver is measured, and the power of the signal transmitted by the transmitter is adjusted to attain a desired OSNR at the receiver.

Abstract: A high speed DWDM optical transmission system that reduces a fiber dispersion limit without reducing the total channel count of a multi-wavelength optical signal. The system achieves such reduction in the fiber dispersion limit by employing a multi-wavelength optical signal comprising a gap-free band structure, and performing per-band dispersion compensation on the optical signal by adjusting residual dispersion values associated with one or more of the bands. In one embodiment, the system includes a first dispersion compensation module (DCM) that provides a dispersion-compensated multi-wavelength optical signal containing wavelength-dependent residual dispersion to a band splitter. The band splitter separates the dispersion-compensated optical signal into a plurality of bands such that no band gaps are formed between adjacent bands, and provides each band to a respective second DCM configured to reduce the residual dispersion associated with that band to a predetermined range of residual dispersion values.

Abstract: A Dense Wavelength Division Multiplexed (DWDM) optical transmission system that compensates for unequal channel performance over an extended fiber transmission distance.