| 摘要 |
<p>A trigger pulse generator is coupled to a recurrence frequency generator, which is additionally connected to a noise source, and produces h.f. rectangular pulses across the terminals of a tunnel diode. The pulses are modulated by the h.f. components of the noise signal to obtain a noise modulation of the I/T recurrence frequency of the pulse train. The separation between two pulses remain instant and respectively act for transmission or exploration. Consequently, a h.f. transmission pulse, reflected by a target and received by an antenna as an echo, can be collected by a discriminator as a low frequency signal at the input of a l.f. amplifier. However, unwanted signals in the form of a permanent current, or even pulses, produce no effect. The system may be used in a missile proximity fuse.</p> |
