A critical examination of the modal expansion method to study discontinuities in waveguide based microwave components is made. We consider the case of E-plane metal insert filters as part of our study to assess the places where maximum electric fields occur so as to cause damage by multipaction in a high vacuum environment. Comparisons are made with results obtained using commercially available soft wares.

No abstract

Compact high power diplexer has been designed for Mars Orbiter Mission (MOM) spacecraft of Indian Space Research Organization (ISRO), launched in November-2013. This is realized using waveguide combline filter structures with an additional objective of multipaction-free operation. Used in Sband TT&C transponder that handles continuous RF power of 200W in telemetry path besides an isolation of >145dB to telecommand path. Diplexer design, realization and test results are presented. Mission performance of on-board diplexer is normal.

No abstract

No abstract