Abstract: An input/output module in a system for testing the functionality of an elronic system. The input/output module includes a plurality of input connections for receiving signals from the electronic system and a number of output connectors with different structural characteristics adapted for mating with plugs of correspondingly different structural characteristics to direct signals to another component of the testing system. For example the input/output module can include a plurality of BNC type plugs for signals of a first type and TNC type plugs for signals of a second type. This arrangement inhibits unintended cross connections between specific output connectors.

Abstract: A neural network for classifying input vectors to an outcome class under the assumption that the classes are characterized by mixtures of component populations having a multivariate Gaussian likelihood distribution. The neural network comprises an input layer for receiving components of an input vector, two hidden layers for generating a number of outcome class component values, and an output layer. The first hidden layer includes a number of first layer nodes each connected receive input vector components and generate a first layer output value representing the absolute value of the sum of a function of the difference between each input vector component and a threshold value. The second hidden layer includes a plurality of second layer nodes, each second layer node being connected to the first layer nodes and generating an outcome class component value representing a function related to the exponential of the negative square of a function of the sum of the first layer output values times a weighting value.

Abstract: A system for unwrapping an artificial neural network (ANN) to determine the tilization and functionality of the nodes uses a network generator for generating an initial ANN architecture. Training and pruning processors operate to generate minimal ANN architectures having increasingly lower levels of classification accuracy. A network analyzer uses an analysis controller to receive minimal ANN architectures from the pruning processor. A connection analyzer operates on the minimal ANN architectures to identify the inputs to the minimal ANN architecture and determine the information represented by and contained in the network inputs. A node analyzer, coupled to the connection analyzer, then defines the utilization and functionality of each node in the minimal ANN architecture in terms of known functions.

Abstract: A software object for providing a display of a scrolling real-time graph includes a window, a fixed axis within the window, a scrolling axis within the window, axis labels within the window, a plot within the window, and facility for viewing obscured regions of the graph along the scrolling axis.

Abstract: A projectile trajectory and source location system and method identifies, calizes, and displays a projectile trajectory relative to one or more stationary objects, such as buildings in an urban environment. The system includes a sensor array and trajectory location calculator that sense conditions generated by the projectile, such as an acoustic signature, and calculate a set of ranges to the trajectory. A ranging system and range comparison calculator measure ranges to one or more stationary objects and compare those ranges to the set of ranges to the trajectory. A display displays the trajectory relative to the stationary objects including unobstructed portions of the trajectory, obstructed portions of the trajectory and the located source of the projectile. A tracking system and dynamic reprocessor track the movement of an observer, dynamically reprocess the relative trajectory location, and update the display of the relative trajectory location in response to the observer's movement.

Abstract: A passive target detection system for use with a moving platform which indes a module for postulating modeled target signals based upon a number of factors including at least one factor selected from the group consisting of signal beam pattern, frequency, non-linear signal progression and carrier movement; a receiver for receiving signals from a target; and a comparison unit for comparing the signals with the modeled target signals, for determining location of the target.

Abstract: A method for generating a thinned array having an optimal directional response wherein an initial population of possible element occupancy patterns is generated and a relative fitness value for each of the element occupancy patterns in the initial population is determined. Successive populations are generated by manipulating the element occupancy patterns using reproduction, crossover, mutation, elitism, and equality operators. The array response of each occupancy pattern in the successive population is evaluated to determine a fitness value for each. The process of generating and evaluating successive populations is repeated for a specified number of generations, until the maximum population fitness does not significantly increase between generations, or until the population diversity decreases.

Abstract: A testing apparatus for determining the integrity of an electrical cable. ccessive portions of electrical cable pass through an aqueous electrolyte with a distance measurement unit providing an indication of the position of a portion of the cable located in the electrolyte. A capacitance measurement unit connects to a selected conductor in the cable and to an electrode in the electrolyte to continuously generate a measured capacitance signal. An X-Y plotter produces an output that displays the measured capacitance as a function of the length of the cable passing through the electrolyte.

Abstract: There is disclosed an exploder for an underwater weapon which periodically adiates an acoustic signal and activates the weapon only when the echo signal has the same phase as the radiated signal. Thus, echoes from any air-water interface are disregarded.

Abstract: A data compression system includes an image preprocessor for generating a digitized, formatted set of pixels which is passed to an image transformer. The image transformer generates a set of wavelet coefficients from the formatted set of pixels via a series of one-dimensional wavelet transforms. A compression processor selects a subset of the wavelet coefficients for retention based on areas of interest in the original image and the position of coefficients within the set of coefficients. The compression processor then builds a compressed image file using a coefficient location identifier to reduce the size of the addresses that indicate the position of the selected coefficients within the set.

Abstract: A system for generating a minimal artificial neural network (ANN) architecture having as inputs the minimal number of features necessary to discriminate between event classes. A network generator generates an initial ANN architecture. A training processor generates a trained ANN by training the initial ANN to a desired degree of accuracy. A pruning processor prunes the trained ANN by removing interconnections and nodes from the trained ANN. The training processor and pruning processor continue to train and prune the ANN until a minimal network architecture having the class discrimination features as its only inputs is obtained.

Abstract: A signal shift compensation system and method compensates for a shift in a ignal, such as a Doppler shift in an acoustic signal. The system includes a signal sampler for oversampling the shifted signal at a fixed oversampling rate to establish an oversampled shifted signal digital value sequence. The fixed sampling rate is greater than the typical sampling rate, such as the Nyquist rate, of the signals by an oversampling factor. The system further includes a compensation downsampler for decimating the oversampled Doppler shifted signal according to a downsampling factor to establish a decimated digital value sequence. The downsampling factor is determined according to the oversampling factor by which the signal is oversampled and an estimate of the (Doppler) shift value. In one example, the downsampling factor is equal to the oversampling factor divided by a Doppler multiplier reflecting the Doppler shift.

Abstract: A neural network comprising an input layer, two hidden layers for generating an number of outcome class component values, and an output layer for classifying input vectors to an outcome class, under the assumption that the outcome classes are characterized by mixtures of component populations with each component population having a multivariate Gaussian likelihood distribution. The first hidden layer includes a number of first layer nodes each connected receive input vector components from the input layer and generates in response a first layer output value representing the absolute value of the sum of a function of the difference between each input vector component and a threshold value.

Abstract: A neural network for classifying input vectors to an outcome class, under the assumption that the outcome classes are characterized by mixtures of component populations, with each component population having a multivariate non-Gaussian likelihood distribution. The neural network comprising an input layer for receiving the components of the input vector, two hidden layers for generating an number of outcome class component values, and an output layer that identifies an outcome class in response to the outcome class component values. The first hidden layer includes a number of first layer nodes each connected receive input vector components from the input layer and generating in response a first layer output value representing a selected first layer power of the absolute value of the sum of the difference between a function of each input vector component and a threshold value.

Abstract: A system for determining the velocity and trajectory of an underwater vehe comprises a data acquisition processor coupled to a plurality of sensors providing depth, heading, pitch and yaw data for the underwater vehicle. The acquisition processor collects data from the sensors, correlates and assembles the collected data into batches and processes the batches to determine vehicle velocity and trajectory of the vehicle relative to an earth-fixed coordinate system.

Abstract: An intrusion detection system. An RF energy source transmits energy into a ransmission cable that has a characteristic impedance subject to change by deformation of the cable. The cable is buried along a path that corresponds to a perimeter to be monitored. When an intruder places weight in the vicinity of the cable, the cable deforms and changes its characteristic impedance. Consequently a portion of energy transmitted into the cable reflects back where time-domain or frequency-domain reflectometry apparatus uses the reflected energy to identify the location of the intrusion along the cable and provide other characteristics of the intruder.

Abstract: An underwater sensing device for measuring or sensing an underwater condin proximate the floor of an ocean, lake or similar body of water. The sensing device includes an underwater sensing device mounting member and an underwater sensing device sensor, such as a hydrophone, mounted on the mounting member. The mounting member has known acoustic properties including a thickness and a largest dimension, each of which is a function of an acoustic wavelength in the underwater environment. The sensing device can also include acoustic diffraction reducing members disposed around the edges of the mounting member. The sensing device can also include first and second underwater sensors disposed on either side of the mounting member so that one of the sensors faces away from the underwater floor. An underwater sensing device switch, such as a gravity switch, activates the sensor that faces away from the underwater floor.

Abstract: A system for accurate guidance of a vessel and precise deployment of undea cable or pipe includes cable control sensors for monitoring cable length, payout rate, and cable tension; navigation sensors for monitoring vessel position, heading, and speed; and environmental sensors for monitoring the water depth and current profile. A cable navigation control processor uses data collected by the cable control sensors, navigation sensors, and environmental sensors and compares this data with a predetermined cable payout plan to compute the ideal vessel heading and speed and the appropriate cable payout rate.

Abstract: A simulated suspended mine retrieval system is described. It snares a simted suspended mine at sea that is comprised of an anchor, a buoy and a tether connecting the anchor and buoy. The retrieval system has a cable connected to a loop for snaring the simulated suspended mine. In operation the retrieval system is towed from a vessel and the loop passes over the mine and strikes the tether. When this happens the loop has a shackling arrangement that snares the tether and is of such a size that it cannot slip over the mine. This enables the simulated suspended mine to be hoisted upon the towing vessel.

Abstract: An integrated torpedo sonar signal processor having an integrated analog-digital conversion component is provided. The torpedo sonar signal processor has four groups of low-pass filtered analog-to-digital converters, each group containing thirteen converters. The output of a group (thirteen converters) is a serial data signal which is outputted to a field programmable gate array which, in turn, converts the combined signal to parallel data word. The parallel data word is outputted to a first digital signal processor which in turn outputs to a second dual-port digital signal processor, the processor providing prefiltering and space-time processing. The output signal is then sent to a beamformer dual-port digital signal processor which has an attached external memory. The beamformer signal is then outputted to a signal processor component containing four dual-port digital signal processors and a common external memory.