| 摘要 |
An FM/CW radar system which uses a single duplexed antenna, in which high degree of isolation of the transmission signal from the receiver is provided by passive power limiter devices employing the subsidiary resonance mode of narrow linewidth ferrite materials. In devices which are magnetically biased for operation in the subsidiary resonance mode, strong r.f. fields resonantly couple to spin waves, thus causing power absorption for signals at the frequency of incidence which exceed a predetermined threshold. A signal exceeding the threshold is attenuated over a narrow band at the frequency of incidence while the weak FM/CW target echo return signals are transmitted to the receiver with very low loss, provided their frequency displacement is of the order of 15 MHz from the frequency of incidence.
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