USA As Represented by Secretary of the Navy

Vincent K McDonald

Jack R Olson

William H Marn

Robert B Williams

Barbara J Sotirin

Alan Fronk

J Mark Stevenson

Christopher Lawson Fletcher

Susan G Briest

The invention provides an automatic gain control system that is implemented by digital hardware. The digital hardware determines the range of a set of digital data values, and then examines each digital data value in a sequence. An index counter increments a sample count index i each time a new digital data value is examined and determines the absolute value of the i digital data value. The digital hardware also counts both the number j of digital data values that exceed a high percentage value of the range, and the number k of digital data values that are less than a low percentage value of the range as the digital hardware runs through the sequence. If the digital hardware determines that a digital data value is greater than the high percentage value, the ratio j/i exceeds a first threshold value, and the gain level is not set to the lowest gain level, then the gain is decreased. If the digital hardware determines that a digital data value is less than the low percentage value, the ratio k/i exceeds a second threshold value, a predetermined interval of time has elapsed, and the gain level is not set to the highest gain level, then the gain is increased.

Automatic gain control

A system for determining the time between the receipt of two different sils, includes a voltage ramp generator which generates a time dependent voltage signal upon receipt of a timing pulse at a time T.sub.1, and provides the instantaneous value of the voltage signal when the voltage ramp generator receives an input signal having a predetermined threshold value at time T.sub.2. A data processor coupled to receive the voltage signal, generates the timing pulse, and determines a time difference .DELTA.T from the voltage signal, where .DELTA.T=T.sub.2 -T.sub.1.

System for determining time between events using a voltage ramp generator

Growing community of inventors

San Diego, CA, United States of America

Vincent K McDonald