Patent ID: 6281833
Filing Date: 2001-08-28
Classification: G01S

Abstract:
A timing and control apparatus of a preprocessor in a pulsed radiation system for detecting echo signals; said pulsed radiation system including a radiation detector, receiver, analog-to-digital converter, system clock signal, pulse repetition interval trigger input, and target range and velocity estimates; said timing and control apparatus comprising:(a) range gate delay means for generating a range gate delay being comprised of an initial delay and one or more incremental delays; the initial delay corresponding to range at a first pulse repetition interval, and the incremental delay corresponding to velocity;(b) dividing means for generating from said range gate delay a coarse delay and a fine delay; said coarse delay representing an integer number of analog-to-digital sampling intervals of the range gate delay; said fine delay representing a difference between the range gate delay and the coarse delay, and expressed as an integer number of programmable delay increments;(c) first programmable delay means for retarding the phase of the system clock signal by said fine delay;(d) second programmable delay means for generating a delayed trigger by retarding a pulse repetition interval trigger by said fine delay; and(e) counting means, responsive to said first and second programmable delay means, for initiating analog-to-digital conversion of an echo signal a period of time after the delayed trigger of 1(d); said period of time given by said coarse delay;whereby a range gate is made to coincide with the beginning of the echo signal.