Direct Analytical Synthesis of Broadside Inline Antenna Arrays

This work proposes an analytical method to synthesize inline series-fed arrays as cascade of several 2-port sections. Starting from one electromagnetic simulation of a core element, several identical elements are then cascaded by suitable interconnecting transmission lines, thus synthesizing the array without further optimizations. The technique is valid at a single frequency, but also constitutes a good starting point for subsequent bandwidth enlargement. A complete design example, simulated and measured on microstrip technology, validates the method for a 31 GHz 5-element array.