Brian R. La Cour

Ensemble‐based Bayesian detection and tracking

This paper introduces a novel approach to Bayesian tracking in which the posterior distribution is represented by a random sample or ensemble of possible target states. Such a representation may be viewed as a special case of the traditional particle filter approach wherein all particles maintain strictly uniform weights. Measurement updates are performed using a Markov chain Monte Carlo technique, which has been adapted to use multiple chains and a variable pseudo temperature akin to that used in simulated annealing. The general formalism is illustrated in an example of sonar‐based target tracking for antisubmarine warfare. For this example, specific motion models and likelihood functions are developed for both target and clutter hypotheses. The technique is examined in the context of results from a recent multistatic seatrial using an echo repeater target and compared against those of a traditional particle filter. [This work was supported by ONR Contract No. N00014‐00‐G‐0450‐21.]

A Locally Deterministic, Detector-Based Model of Quantum Measurement

This paper describes a simple, causally deterministic model of quantum measurement based on an amplitude threshold detection scheme. Surprisingly, it is found to reproduce many phenomena normally thought to be uniquely quantum in nature. To model an

Classical emulation of a quantum computer

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Range-sensitive Bayesian passive sonar tracking

N-dimensional pure state, the model uses

Computationally efficient Bayesian tracking

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Subspace projection method for unstructured searches with noisy quantum oracles using a signal-based quantum emulation device

N complex random variables given by a scaled version of the wave vector with additive complex noise. Measurements are defined by threshold crossings of the individual components, conditioned on single-component threshold crossings. The resulting detection probabilities match or approximate those predicted by quantum mechanics according to the Born rule. Nevertheless, quantum phenomena such as entanglement, contextuality, and violations of Bell’s inequality under local measurements are all shown to be exhibited by the model, thereby demonstrating that such phenomena are not without classical analogs.