This paper suggests a new method for designing of planar eight port waveguide mono-pulse comparator. Planar eight port waveguide mono-pulse comparator acts as a four-way in-phase power divider in a transmitting mode and as a mono-pulse sum and difference combining hybrid in the receiving mode. The short-slot directional coupler is converted to an equivalent magic tee by adding dielectric-slab-filled waveguide phase shifter. Four such hybrids are connected appropriately using H-plane bends to form a compact planar eight port waveguide mono-pulse comparator. Simulation results with Ansoft HFSS software are presented, which verify good performance.
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