Microwave frequency transmit-receive assemblies - has resonant cavities coupled to circular wave guides via wave guide slots

摘要

A rectangularly polarised wave generated by a semiconductor diode oscillator (11) passes through a quarter wave impedance transformer (12) to a circular waveguide (13). This allows the wave to pass to a truncated conical shaped revolving antenna (14). A rectangular resonant cavity (15) is coupled to the waveguide by a longitudinal rectangular window (16) and is attached to the quarter wave transformer by two screw threads (23, 26). The cavity contains a microwave detector diode mounted on a conducting pillar (30). Tuning and impedance matching is enabled by a piston (31). Two assemblies are carefully aligned on a plate and one is used for transmission and the other for reception.