Design and Realization of SIW-Based Feeding Network with Tapered Transmission Lines for Monopulse Antenna

The main distinction between monopulse antennas and other similar antennas used for different purposes lies in the feeding network properties. This paper focuses on the design and realization of a feeding network based on substrate-integrated-waveguide (SIW) for an Industrial, Scien-tific, and Medical (ISM) band monopulse antenna excitation. The tapered transmission lines is utilizied in the design to improve impedance matching and to simplify integration with other planar structures. The realization of SIW-based feeding network utilizes Rogers RO-4003C dielectric substrates with the thickness of 1.524 mm. The results of measurement at the frequency of 2.4 GHz yield the isolation of around −15 dB with the phase difference close to 180<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">○</sup>, and the reflection and transmission coefficients of around −15 dB and −3dB, respectively, in which these agreed with the simulation.