Importance

Loading Importance Indicators...

Abstract

An electronically variable active analog delay line utilizes cascaded differential transconductance amplifiers with integrating capacitors and negative feedback from the output to the input of each noninverting amplifier. The delay of each section may be controlled through a conductor having distributed resistance connected at distributed points to the transconductance control terminal of the amplifiers with a controllable voltage gradient between the two ends of the conductor. Signals may be coupled in and added to a propagating signal using capacitors, or transconductance amplifiers which may also be of the differential transconductance type, particularly when coupling signals from a second delay line having substantially the same propagation velocity. The differential transconductance amplifiers may be arranged in pairs, each pair with positive feedback from the output terminal of the second to the input terminal of the first amplifier of the pair through a third differential amplifier with positive feedback from its own output terminal. The transconductances of the cascaded amplifiers are controlled in each section to produce the desired time-constant (delay) of the section, and the transconductance of the positive feedback amplifier is controlled for stable operation and gain control of the section.

Loading the Abstract Image...

First Claim