Abstract: A reconfigurable backplane assembly for a programmable digital radio and consisting of a printed wire matrix plate including connectors for electronic circuit modules, power cables, RF cables, and optical cables with the connectivity between digital signals being dynamically reconfigurable electronically and with connectivity between power signals, optical signals and RF signals being manually reconfigurable.

Abstract: A system that partitions or divides the functions of a radio into channels and divides the functions of each channel into two major functions: 1) antenna interface and power amplification; and 2) hardwired mixing, modulation/demodulation and signal processing and further partitions the mixing through signal processing functions into the functions of a) programmable analog mixing and b) programmable digital modulation/demodulation and signal processing. Control and user interface functions, if needed for a particular application can also be functionally partitioned.

Abstract: A programmable digital radio is configured to perform navigation functions. A receiver in the programmable digital radio receives analog signals from a navigation unit and digitizes the analog signals to produce digital navigation signals. The digital navigation signals are processed digitally and valid navigation information is determined. Processing includes generation of baseband signals including in-phase signals and quadrature signals, AM demodulation, filtering, decimating, demultiplexing, discrete fourier transformation, and function processing according to a selected function. The selected functions may include Localizer, Marker Beacon and Glideslope.

Abstract: A common transmit module of a programmable digital radio has a digital submodule which receives a bit stream and produces a modulated IF signal, and an analog submodule which receives the modulated IF signal and converts the modulated IF signal to a frequency corresponding to a specific type of radio function. The digital submodule includes (a) a sequential/parallel instruction set processor for signal processing and control, (b) a reconfigurable format unit, and (c) a modulator which receives the output signals of the reconfigurable format unit and produces the modulated oscillation signal.

Abstract: A digital submodule is included in a software programmable common receive module for receiving IF signals and producing a serial bit stream. The digital submodule is programmable based on a selected application of a plurality of radio applications and, if present, a selected function of a plurality of functions of the selected radio application. The digital submodule may include an analog to digital converter for converting IF signals received from an analog submodule into digital signals. The digital signals are supplied to a programmable signal processing unit which is configured, according to the selected radio application and, if present, the selected function, to perform control functions, processing and analysis of the digital signals and generate output signals. The output signals are then formatted by a formatting unit producing formatted digital signals. The formatted digital signals are then supplied to a system bus.

Abstract: A FIR interpolator which uses a zero order hold to add samples in-between original samples of a digital input stream. The use of zero order hold with a FIR interpolator reduces output harmonics as compared to the use of conventional zero fill. Moreover, a computation method has been developed to greatly reduce the amount of computation needed by combining the zero order hold and the FIR filter. The output of the FIR interpolator can then be interpolated by a Spline interpolator to further interpolate the input stream. The combination of zero order hold FIR interpolation with Spline interpolation provides an efficient, cost effective technique of interpolating a digital input stream while producing relatively small output harmonics.

Abstract: A programmable digital radio is configured to perform transponder functions. A receiver in the programmable digital radio receives analog signals from an interrogator and digitizes the analog signals to produce digital interrogation signals. The digital interrogation signals are processed digitally and valid interrogations are detected. Processing includes detection of pulses, determination of each pulse's threshold, determination of intervals between pulses and whether the intervals meet mode criteria, and determination of priority of output of digital messages encoded in the pulses. At least one message is supplied to a transmit module in the programmable radio. The transmit module performs diversity processing on the received message to determine to which received signal to reply, produces reply data and modulates the reply data to produce intermediate frequency signals. The intermediate frequency signals are then converted to analog signals which are transmitted to the interrogator.

Abstract: A method and apparatus for registering two images from different sensors including receiving a first and second image, detecting hot spots in the first and second images, respectively, pairing each of the hot spots in the first image with all the hot spots in the second image that are within a predetermined mapping distance to produce a mapping between the hot spots of the first and second images, refining the mapping produced by selecting one of the hot spots of the second image for each of the hot spots of the first image utilizing a least mean squares method, producing a registered image from the refined mapping, and outputting the registered image.