A five-channel quasi-optical multiplexer of 12- to 90-GHz frequency range

An effective five-channel quasi-optical multiplexer, which distributes microwave signals of the frequency range of 12–90 GHz on five frequency channels, $Ku$, $K$, $Ka$, $U$, and $E$ (frequency ranges of standard single-mode waveguides), or combines these channels into a single wave stream, has been developed for the first time. A relatively homogeneous characteristic with a total loss level of about 1.5 dB is achieved in 90% of each range band. A detailed analysis of diffraction and ohmic losses in the frequency channels of the multiplexer has been carried out.