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Generalized digital filter is a special purpose computer. The term digital filter is an algorithm which accepts an input sequence of numbers and transforms it into an output number sequence. The organization of the computer, the logical design and synthesis, and experimentaion with the computer in two sampled data control systems is discussed.
Narrow band optical filter is electronically tunable over a large wavelength region. The filter utilizes collinear acousto-optic diffraction in an optically anisotropic media.
Blocking filter effects on long-wavelength rejection of ultraviolet bandpass filter
Limited memory optimal filter theory, output and standard filter divergence due to errors
Adaptive filtering to prevent divergence observed in application of Kalman filter to orbit determination
Adaptive filter for estimating system noise inputs from actual residuals developed to control Kalman filter in satellite orbit estimation
Filtering optimization prior to limiting digital signals in strong noise, detailing bandwidth choice of single pole low pass filter
Adaptive filtering to prevent divergence observed in application of Kalman filter to orbit determination
Filters, formed by combinations of distributed RC elements with positive-feedback voltage amplifiers, provide transfer functions similar to those the heavier LC filters ordinarily employ. They also provide signal amplification.
Self-tuning filter automatically adjusts its center frequency to track signal frequency. This permits the use of a filter with a bandwidth smaller than the range of input signal frequencies.
Resistance-capacitance RC filter coupled to a high input impedance receiver preamplifier provides signal isolation from an RF transmitter. High isolation is achieved by minimizing the inductive impedance to ground and using the distributed capacitance of the filter components.
Tuneable adjustable solid state bandwidth filter using N path system for low pass to bandpass filter transformation
Book on stochastic processes and filtering theory covering probability theory, Markov processes, linear and nonlinear filters, etc
High purity filter unit saves time and expense in laboratory operations and improves purity of liquids processed. Any but most viscous liquids are processed by modified unit equipped with appropriate filter medium. Unit's use eliminates much glassware cleaning tedium.
Numerical analyses of error covariance matrix in linear filtering problem, computational errors in Kalman filtering, and coasting flight equations
Filter cassette eliminates or substantially reduces contamination of filter media by extraneous material and facilitates handling.
Electronically tunable lithium niobate filter utilizes acoustic-optic diffraction for tuning laser to desired frequencies. Filter placed inside laser cavity diffracts incident optical signal of one polarization into orthogonal polarization by collinearly propagating acoustic beam to desired wavelength.
A method for a computer-aided design of a class of optimum filters, having specifications in the frequency domain of both magnitude and phase, is described. The method, an extension to the work of Steiglitz, uses the Fletcher-Powell algorithm to minimize a weighted squared magnitude and phase criterion. Results using the algorithm for the design of filters having specified phase as well as specified magnitude and phase compromise are presented.