Radar with permanent echo suppression - compensates for delay line attenuation to compensation for delay line losses to ensure reliable operation with short pulses

摘要

A radar system includes a permanent echoe suppression. It provides phase-coherent continuation of a pulse consisting of a number of periods on a h.f. oscillation. An electrical delay line has a delay time of half the pulse duration, and a doubled electrical length equal to a multiple of the period of the HF oscillation. The delay line is connected to an amplifier which is not matched to its impedance. - The input of one amplifier unit forms the overall input. the output of the amplifier unit is connected to the input of the dealy line and forms the overall output. The amplifier circuit units have positive feedback and have negative output impedance, their outputs being connected to the delay line. The negative output impedances are such that the correct mismatch is obtained.