RF Routing matters in RADAR. The challenge is protecting the sensitive receiver while efficiently routing high-power pulses. Ferrite circulators, directional couplers, and duplexers solve these routing and protection problems. These components enable efficient, safe, and high-performance RADAR operation in modern solid-state and magnetron-based systems. Duplexer/Circulator is an Antenna‑Sharing Switch. An electronic switch that allows one antenna to serve both transmission and reception, with the advantages over older gas‑discharge TR cells: faster switching, higher reliability, and better isolation.
Ferrite Circulators’ core principle is that a circulator is a non-reciprocal, multi-port RF device that routes energy in one direction. Ferrite material acts as a phase shifter, enabling this one-way energy flow. Circular resonant cavities where E‑lines are perpendicular to the end walls and H‑fields form complementary standing waves. The circulator’s primary placement: the duplexer section of the RADAR system, replacing older TR/ATR cells and functioning as the modern duplexer. A directional coupler is a device that samples a small, known fraction of RF power. With a –30 dB attenuation, a 10 µW sample corresponds to 100W on the main line. This sampling is essential for calibration, monitoring, and safety.