Abstract: A method for evaluating a received signal varying over an interval includes: (a) obtaining a data sample and a sample time; (b) determining whether the sample exceeds a previous exceeded extremum of the signal; (c) if the sample does not exceed an exceeded extremum, storing the sample; (d) if the sample exceeds the an exceeded extremum, in no particular order: (1) extracting and storing cycle information involving the exceeded extremum; and (2) replacing an earliest exceeded extremum with the sample; (e) outputting first selected data from a storage unit; (f) determining whether the interval has completed; (g) if the interval has not completed, repeating steps (a) through (f); (h) if the interval has completed, checking whether an output buffer is empty; (i) if the buffer is not empty, outputting second selected data from the buffer; j) if the buffer is empty, terminating the method.

Abstract: A system and method for demodulating an optical differential-phase-shift-keyed (DPSK) input signal using a Fabray-Perot etalon filter. In one embodiment the system receives a transmitted wavefront from the etalon filter and uses a detector to generate an electrical waveform from the transmitted wavefront. A comparator is used to receive an output from the detector and to generate a signal in accordance with each phase shift (i.e., bit transition) in the optical DPSK input signal. A latching flip-flop receives an output from the comparator and generates a digital signal representative of the bit pattern of the DPSK input signal. The system and method does not require the precisely matched dual optical paths of a Mach-Zehnder interferometer, and therefore is substantially less susceptible to thermal effects that could influence the operation of a conventional Mach-Zehnder interferometer in DPSK demodulation operations.

Abstract: An optical communications system includes a focal element configured to transmit a signal, an aperture configured to focus the signal onto the focal element, and a phase change layer positioned on at least a portion of a surface of the aperture, wherein the phase change layer is configured to shift a phase of the signal.

Abstract: A system and method for determining remaining fatigue life of a component experiencing stress/strain cycles. In one embodiment the fractional life expended per clock cycle of the component is determined and multiplied by a data type value indicating whether a full cycle, half cycle or no stress/strain amplitude information was present during a given clock cycle. The product is then summed with the result of the previously clock cycle, to produce a running total of the fractional life expended. The running total is then subtracted, at each clock cycle, from an initial fatigue life value, and the output represents the residual fatigue life remaining for the component.

Abstract: A method for evaluating a received signal varying over an interval includes: (a) obtaining a data sample and a sample time; (b) determining whether the sample exceeds a previous exceeded extremum of the signal; (c) if the sample does not exceed an exceeded extremum, storing the sample; (d) if the sample exceeds the an exceeded extremum, in no particular order: (1) extracting and storing cycle information involving the exceeded extremum; and (2) replacing an earliest exceeded extremum with the sample; (e) outputting first selected data from a storage unit; (f) determining whether the interval has completed; (g) if the interval has not completed, repeating steps (a) through (f); (h) if the interval has completed, checking whether an output buffer is empty; (i) if the buffer is not empty, outputting second selected data from the buffer; 0) if the buffer is empty, terminating the method.

Abstract: A method, apparatus and computer program product are provided in which information identifying a stress/strain range cycle and the time duration of the stress/strain range cycle associated with the component is received. The maintenance value based upon the actual service life expended during the stress/strain range cycle and the time duration of the stress/strain range cycle is then determined. As such, the component need not be prematurely retired and appropriate compensation or other accounting may be provided for the effective extension in the service life of the component. The determination of the maintenance value may be based on the time duration of the stress/strain range cycle, a residual lifetime and a total number of life cycles for the identified stress/strain range cycle. The retirement of a component may also be recommended in certain instances.

Abstract: A system and method for demodulating an optical differential-phase-shift-keyed (DPSK) input signal using a Fabray-Perot etalon filter. In one embodiment the system receives a transmitted wavefront from the etalon filter and uses a detector to generate an electrical waveform from the transmitted wavefront. A comparator is used to receive an output from the detector and to generate a signal in accordance with each phase shift (i.e., bit transition) in the optical DPSK input signal. A latching flip-flop receives an output from the comparator and generates a digital signal representative of the bit pattern of the DPSK input signal. The system and method does not require the precisely matched dual optical paths of a Mach-Zehnder interferometer, and therefore is substantially less susceptible to thermal effects that could influence the operation of a conventional Mach-Zehnder interferometer in DPSK demodulation operations.

Abstract: A system and method for determining remaining fatigue life of a component experiencing stress/strain cycles. In one embodiment the fractional life expended per clock cycle of the component is determined and multiplied by a data type value indicating whether a full cycle, half cycle or no stress/strain amplitude information was present during a given clock cycle. The product is then summed with the result of the previously clock cycle, to produce a running total of the fractional life expended. The running total is then subtracted, at each clock cycle, from an initial fatigue life value, and the output represents the residual fatigue life remaining for the component.

Abstract: A semiconductor active waveguide optical crossbar switch to allow optical signals to be routed to any number of ports with no net attenuation of signal strength. The optical crossbar switch is comprised of a network of optical waveguides wherein both lateral and transverse carrier confinement is provided. Redirection of the optical waveguide is accomplished by means of total internal reflectance turning mirrors. Furthermore, the optical waveguides are formed such that electrical current may be applied to the semiconductor structure to amplify the optical signal travelling therein. Electro-absorption switches formed from distinct metallic contacts overlying portions of the optical waveguides amplify the optical signal travelling through the waveguide underneath the switch if sufficient electrical stimulation is applied to the switch.