The joint probabilistic data-association filter (JPDAF) [1] is a statistical approach to the problem of plot association (target-measurement assignment) in a target tracking algorithm. Like the probabilistic data association filter (PDAF), rather than choosing the most likely assignment of measurements to a target (or declaring the target not detected or a measurement to be a false alarm), the PDAF takes an expected value, which is the minimum mean square error (MMSE) estimate for the state of each target. At each time, it maintains its estimate of the target state as the mean and covariance matrix of a multivariate normal distribution. However, unlike the PDAF, which is only meant for tracking a single target in the presence of false alarms and missed detections, the JPDAF can handle multiple target tracking scenarios. A derivation of the JPDAF is given in. [2]
The JPDAF is one of several techniques for radar target tracking and for target tracking in the field of computer vision.
A common problem observed with the JPDAF is that estimates of closely spaced targets tend to coalesce over time. [3] [4] This is because the MMSE estimate is typically undesirable when target identity is uncertain. [5]
Variants of the JPDAF algorithm have been made that try to avoid track coalescence. For example, the Set JPDAF [6] uses an approximate minimum mean optimal sub pattern assignment (MMOSPA) instead of an approximate MMSE estimator. The JPDAF*, [7] modifies how the target-measurement association probabilities are computed, and variants of the global nearest-neighbor JPDAF (GNN-JPDAF) (a best-hypothesis tracker) [8] use the global nearest neighbor (GNN) estimate in place of the mean but compute the covariance matrix as in the normal JPDAF: as a mean-squared error matrix.
singleScanUpdate
function that is part of the United States Naval Research Laboratory's free Tracker Component Library. [9] The sample code in demo2DDataAssociation
demonstrates how the algorithms can be used in a simple scenario.Linear prediction is a mathematical operation where future values of a discrete-time signal are estimated as a linear function of previous samples.
In statistics and control theory, Kalman filtering is an algorithm that uses a series of measurements observed over time, including statistical noise and other inaccuracies, to produce estimates of unknown variables that tend to be more accurate than those based on a single measurement, by estimating a joint probability distribution over the variables for each time-step. The filter is constructed as a mean squared error minimiser, but an alternative derivation of the filter is also provided showing how the filter relates to maximum likelihood statistics. The filter is named after Rudolf E. Kálmán.
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In statistics and signal processing, a minimum mean square error (MMSE) estimator is an estimation method which minimizes the mean square error (MSE), which is a common measure of estimator quality, of the fitted values of a dependent variable. In the Bayesian setting, the term MMSE more specifically refers to estimation with quadratic loss function. In such case, the MMSE estimator is given by the posterior mean of the parameter to be estimated. Since the posterior mean is cumbersome to calculate, the form of the MMSE estimator is usually constrained to be within a certain class of functions. Linear MMSE estimators are a popular choice since they are easy to use, easy to calculate, and very versatile. It has given rise to many popular estimators such as the Wiener–Kolmogorov filter and Kalman filter.
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A radar tracker is a component of a radar system, or an associated command and control (C2) system, that associates consecutive radar observations of the same target into tracks. It is particularly useful when the radar system is reporting data from several different targets or when it is necessary to combine the data from several different radars or other sensors.
MUSIC is an algorithm used for frequency estimation and radio direction finding.
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The Probabilistic Data Association Filter (PDAF) is a statistical approach to the problem of plot association in a target tracking algorithm. Rather than choosing the most likely assignment of measurements to a target, the PDAF takes an expected value, which is the minimum mean square error (MMSE) estimate. The PDAF on its own does not confirm nor terminate tracks.
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Yaakov Bar-Shalom is a researcher in tracking and sensor fusion. His work is associated with MS-MTT and IMM (interacting-multiple-model) estimator.
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