System for estimating acceleration of maneuvering targets
AssigneeWestinghouse Electric Corp.
InventorElmen C. Quesinberry
Life of this patent
Estimating the term…
Abstract
A radar system of the type utilizing an optimal estimator to process raw range and angle track data for driving a radar antenna, where the tracking computations, range rate, and angular rate of the range vector are utilized in estimating the target velocity vector and the target acceleration vector. The attenuation inherent in the practical estimation of target acceleration is effectively removed for severely maneuvering targets by a compensating system that provides an attenuation factor, and multiplies the estimated acceleration output signal by the reciprocal of such factor. The implement control system is governed by the estimated target position and estimated target velocity from the estimator, and the modified acceleration signal of the compensating system.
Claims10
A radar system for tracking a moving target, comprising:
- (a) antenna means for sensing radar pulses reflected from the moving target;
- (b) means responsive to the reflected pulses to generate a signal representative of the measured target range and a signal representative of the measured angle of error between the antenna line-of-sight and the target;
- (c) means to generate estimation gain factor signals to compensate for external and internal radar system errors, said gain factor signals being derived from signals representative of errors in measuring target range, target velocity, and target acceleration;
- (d) estimating means governed by the generated measured signals and the generated gain factor signals to generate repetitive signals representative of estimated target range, estimated rate of change of target range, and estimated target acceleration, said target acceleration estimation signal being generated in accordance with the value of a selected number of previously generated estimated acceleration signals;
- (e) means to decrement each of the selected number of previously generated estimated acceleration signals a proportional amount in calculating the value of the present estimated acceleration signal;
- and
- (f) compensating means to increase the value of the estimated target acceleration signal to compensate for the attenuation of the previously decremented acceleration estimation signals in accordance with a signal representative of the selected number of previously generated estimation signals and the generated gain factor signals representative of target velocity and acceleration, whereby the increased acceleration signal represents a more accurate representation of a severely maneuvering target.
In a radar system having an estimator for generating signals representative of the estimated velocity and acceleration of a target, said signal of estimated acceleration being generated in accordance with a selected number of previously generated estimated acceleration signals, wherein each of the selected number of previously generated estimated acceleration signals are decremented by a value in accordance with the total selected number to calculate each new estimated acceleration signal, said estimator generating estimator gain factor, velocity and acceleration signals to compensate for external and internal system noise, the method of compensating for the decrementing of each of the previously generated signals in the generation of each new estimated acceleration signal comprising:
- generating a signal TTC representative of the selected number of previously generated signals,
- dividing the velocity gain factor signal by the generated signal TTC,
- adding the result of the last previous step to the acceleration gain factor signal,
- dividing the acceleration gain factor signals by the result of the last previous step to obtain the acceleration compensation factor signals, and
- multiplying the acceleration compensation factor signal by the estimated acceleration signal.
A radar system for tracking a moving target, comprising:
- (a) antenna means for sensing radar pulses reflected from the moving target;
- (b) means responsive to the reflected pulses to generate a signal representative of the measured target range and a signal representative of the measured angle of error between the effective antenna line-of-sight and the target;
- (c) means to generate estimation gain factor signals for effective line-of-sight coordinates to compensate for external and internal radar system errors, said gain factor signals including signals representative of errors in measuring target range, target velocity, and target acceleration;
- (d) estimating means governed by the generated measured signals and the generated gain factor signals to generate repetitive signals representative of estimated target range, estimated rate of change of target range, and estimated target acceleration, said target acceleration estimation signal being generated in accordance with the value of a selected number of previously generated estimated acceleration signals;
- (e) means to decrement each of the selected number of previously generated estimated acceleration signals a proportional amount in calculating the value of the present estimated acceleration signal;
- (f) compensating means to increase the value of the estimated target acceleration signal to compensate for the attenuation of the previously decremented acceleration estimation signals for the effective line-of-sight coordinates in accordance with a signal representative of the selected number of previously generated estimation signals and the generated gain factor signals representative of target velocity and acceleration;
- and
- (g) means to effectively change the increased estimated target acceleration signals to values for geographic coordinates.
Dependencies are inferred from the claim text.