Abstract: An optical receiver system for processing signals output from a polarization diversity detector that includes a plurality of photodetector cells. Each cell provides an signal that includes a phase generated carrier signal having a modulation frequency ? and a sensor signal that has an in-phase component I and a quadrature phase component Q superimposed on the phase generated carrier signal. A plurality of variable gain amplifiers are arranged to produce a plurality of amplified signals. A feedback circuit is connected to the plurality of variable gain amplifiers for controlling the gains thereof. A plurality of demodulator circuits are arranged to receive the amplified signals. The demodulator circuits are arranged to provide for each photodetector cell an I signal output that indicates an amplitude of the in-phase component I and a Q signal output that indicates an amplitude of the quadrature phase component Q.

Abstract: A method for selecting a cell from each member of a tri-cell photodetector array used to detect optical signals output from a multichannel sensor array to indicate interference between two optical signals of unknown polarization incident upon the tri-cell photodetector array comprises selecting a cell in each tri-cell photodetector and collecting a selected number of samples of the signal output for each cell. Each sample has an in-phase AC component I and a quadrature AC component Q. An amplitude sum signal E=I*I+Q*Q is calculated for a predetermined number of samples in the selected number of samples of the signal output for each cell. The signal output of cell in each tri-cell photodetector having the largest value of the amplitude sum signal is selected for further processing.

Abstract: Apparatus for eliminating sign uncertainty in a coherent phase generated carrier demodulator in a multi-channel sensor system has a downconverter array arranged to separate the in-phase component I and the quadrature phase component of the sensor output for each channel. A coordinate transformer uses the in-phase component and quadrature phase component to calculate an arctangent for the phase angle for each channel. A digital signal processor adds 180° to each arctangent calculation for which the tangent is a negative number.

Abstract: Apparatus for eliminating sign uncertainty in a coherent phase generated carrier demodulator in a multi-channel sensor system has a downconverter array arranged to separate the in-phase component I and the quadrature phase component of the sensor output for each channel. A coordinate transformer uses the in-phase component and quadrature phase component to calculate an arctangent for the phase angle for each channel. A digital signal processor adds 180° to each arctangent calculation for which the tangent is a negative number.

Abstract: A method for selecting a cell from each member of a tri-cell photodetector array used to detect optical signals output from a multichannel sensor array to indicate interference between two optical signals of unknown polarization incident upon the tri-cell photodetector array comprises selecting a cell in each tri-cell photodetector and collecting a selected number of samples of the signal output for each cell. Each sample has an in-phase AC component I and a quadrature AC component Q. An amplitude sum signal E=I*I+Q*Q is calculated for a predetermined number of samples in the selected number of samples of the signal output for each cell. The signal output of cell in each tri-cell photodetector having the largest value of the amplitude sum signal is selected for further processing.

Abstract: An optical receiver system for processing signals output from a polarization diversity detector that includes a plurality of photodetector cells. Each cell provides an signal that includes a phase generated carrier signal having a modulation frequency &ohgr; and a sensor signal that has an in-phase component I and a quadrature phase component Q superimposed on the phase generated carrier signal. A plurality of variable gain amplifiers are arranged to produce a plurality of amplified signals. A feedback circuit is connected to the plurality of variable gain amplifiers for controlling the gains thereof. A plurality of demodulator circuits are arranged to receive the amplified signals. The demodulator circuits are arranged to provide for each photodetector cell an I signal output that indicates an amplitude of the in-phase component I and a Q signal output that indicates an amplitude of the quadrature phase component Q.

Abstract: A backplane module adds a second level of PCI bridges to a single board computer to increase the number of slots controllable by a common host processor. This invention provides a configuration that supports common host control of sixteen PCI slots and an Ethernet interface, a universal system bus (USB) and a SCSI interface resident on the common host single board computer.