I. Introduction
Antenna arrays have been an indispensable alternative solution to implementing high-gain characteristics, in particular if radiators are small in terms of their aperture size. Small antennas, as a result of their form factor, have low radiative resistance, and hence low gain. One notable alternative to enhance small antennas' gain is to implement an array geometry. Consequently, the idea of realizing low-profile, low-cost, and efficient monolithic arrays has drawn much attention to planar-based arrays using metal radiators. For instance, a corporate feed network was implemented in [1]–[2], conventional series feed in [3]–[4], a series-parallel combination feed network in [5] and a series feed out-of-line network in [6]. The main drawback that serves as a common denominator in all these methods is unavoidable expanse estate area occupancy, which disqualifies them from been integrable into monolithic microwave circuits. In this work, therefore, we present a new series feed topology that can optimize estate area occupancy without compromising directivity.