Pilot-controlled repeater level - for carrier frequency systems and controls output level using correction signal from following controller

摘要

A differental amplifier (5) has its positive input derived from the controller output (xi). Its negative input is the sum of a reference signal (W) and a correction signal (Ki+1) received from the following controller. The resultant (Yi) controls the gain of the input amplifier (Vi). The output of a second differential amplifier (8), which is the difference between the above (Y1) and the correction signal (Ki+1), is sent as a correction signal (Ki) to the preceding controller. The controller output level is determined only by attenuation changes in the following section of cable. Errors are not spread between sections.