Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 14 of 14 for “"time delay estimation"”.
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Nonlinear filtering for narrow-band time delay estimation
… tracking systems combine estimates of the time difference of arrival (TDoA) between pairs of spatially separated sensors - this work improves those estimates by independently tracking each TDoA using a Bayesian filter. This tracking is particularly useful for overcoming spatial aliasing, …
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Overloaded Array Processing: System Analysis, Signal Extraction Techniques, and Time-delay Estimation
… and the channel is blindly estimated. Multi-user time delay estimation is one of the most important aspects of channel estimation for overloaded array processing. The final chapter of the thesis proposes a low-complexity data-aided time-delay estimation structure for embedding in a Per Survivor …
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Phase Transform Time Delay Estimation to Counteract Spectral Haystacking Effects in Jet Exhaust Flow Measurements
… exhaust in order to estimate the traversal time of the signal. Thrust measurement is possible with enough time delay estimates across different portions of the exhaust. This preliminary study did not take the full array of data necessary to measure thrust, but did validate key aspects of the …
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Estimating time delays between irregularly sampled time series
The time delay estimation between time series is a real-world problem in gravitational lensing, an area of astrophysics. Lensing is the most direct method of measuring the distribution of matter, which is often dark, and the accurate measurement of time delays set the scale to measure distances …
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Estimating uncertainty models for speech source localization in real-world environments
… For source localization, it develops a new time- and frequency-dependent weighting function for the generalized cross-correlation framework for time delay estimation. This weighting function is derived from the speech spectrogram as the result of a transformation designed to optimally …
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Echo Delay Estimation to Aid Source Localization in Noisy Environments
Time-delay estimation (TDE) finds application in a variety of problems, be it locating fractures or steering cameras towards the speaker in a multi-participant conference application. Underwater acoustic OFDM source localization is another important application of TDE. Existing underwater acoustic …
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Data-Driven Localization and Structure Learning in Reverberant Underwater Acoustic Environments
… knowledge such as synchronization and occluder estimation, which are inputs for the following stages of more refined algorithms. Within this framework, we introduce a 2D neural network boundary estimation method that outperforms the existing methods in the literature, and is robust to the large …
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Time Delay Estimate Based Direction of Arrival Estimation for Speech in Reverberant Environments
Time delay estimation (TDE)-based algorithms for estimation of direction of arrival (DOA) have been most popular for use with speech signals. This is due to their simplicity and low computational requirements. Though other algorithms, like the steered response power with phase transform (SRP-PHAT), …
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Localization of Dynamic Acoustic Sources with a Maneuverable Array
… addresses the problem of source localization and time-varying spatial spectrum estimation with maneuverable arrays. Two applications, each having different environmental assumptions and array geometries, are considered: 1) passive broadband source localization with a rigid 2-sensor array in a …
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Comparison of edge turbulence velocity analysis techniques using Gas Puff Imaging data on Alcator C-Mod
… is computed [1, 2]. The other is based on time-delay cross-correlation of successive images used to track the motion of discrete emission structures [3, 4]. Several Gas-Puff-Imaging experiments were conducted to obtain data taken using the GPI Phantom Camera. The analysis of and results …
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Bayesian Estimators, Error Bounds, and Applications to Imaging
… bound to a highly non-linear and more realistic time-delay estimation (TDE) problem which is basic to many signal processing scenarios, including source detection, array processing, surveillance, synchronization in communications, range finding in RADAR, geo-location and tracking in sensor …
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Source localization via time difference of arrival
… which the specific transmitted symbols and the time of the transmitted signal are unknown to the receiving sensors. With the localization of non-cooperative sources, time difference of arrival (TDOA) of the signals received at pairs of sensors is typically employed. A two-stage localization …
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A 3-D Multiparametric Ultrasound Elasticity Imaging System for Targeted Prostate Biopsy Guidance
… using an estimated shear wave propagation time between push excitations to align arrival times, resulting in SWEI imaging of prostate cancer with high contrast-to-noise ratio (CNR), enhanced spatial resolution, and reduced reflection artifacts.</p><p>In Chapter 4, a fully convolutional …
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Development of Robust Correlation Algorithms for Image Velocimetry using Advanced Filtering
… improve the accuracy and robustness of the DPIV estimation. These techniques incorporate the use of the Phase Transform (PHAT) Generalized Cross Correlation (GCC) filter applied to the image cross-correlation. The use of spatial windowing is subsequently examined and shown to be ideally suited …