Low-Cost, Series–Parallel-Fed 2-Bit Phased Array Antenna in $Ku$-Band

In this letter, a low-cost, series–parallel-fed 2-bit phased array antenna for $Ku$ -band 1-D beam scanning application is presented. The compact 2-bit element consists of a microstrip patch with 0 $^\circ /180^\circ$ phase states, dc bias circuits, ground, and a cascaded 90 $^\circ$ phase shifter. Using the proposed element, a series–parallel-fed 9 × 8 array is fabricated and measured. Experimental results demonstrate the beam scanning capability in H-plane within the scan range of $\pm 50^\circ$ , and also show high agreement compared with the simulated ones.