LAUSR

This letter presents a compact, wideband, planar, E-arm folded magic tee at $Ku$ -band for monopulse slotted waveguide antenna array applications. A novel impedance matching structure, an L-shaped septum, is implemented at the magic tee junction, which results in wide impedance bandwidth at all ports. The height of this septum is the same as that of the waveguide height, which allows the design to be very compact. An impedance bandwidth of 22% is achieved for a return loss of 20 dB. The magic tee is manufactured using a high-precision electric discharge machining (EDM) process and followed by the integration of subparts using silver epoxy bonding. Simulation and measured results are compared. Measured amplitude balance of < 0.1 dB, phase balance of <2°, and isolation of better than −35 dB have been achieved. The proposed design is a good technique for the design of broadband, miniaturized monopulse comparators for monopulse antenna array applications.