Lens-enhanced phased array antenna system for high directivity beam-steering

This paper investigates a hybrid steerable antenna topology composed of a small phased array and a significantly larger planar lens-array. The phased array antenna creates an electronically steerable beam, and the lens-array further confines the beam to enhance its directivity. The feasibility of this approach is examined via a 60 GHz design example based on a 4 × 4 phased array and a 24 × 24 lens-array. It is observed that adding the lens-array improves the directivity by 2.5-6 dB for beams within 45° of the boresight direction. Since the lens consumes no power and it may be manufactured inexpensively, this improvement comes at very little cost. The overall depth of the system in this example is 1 cm, which is quite small compared to typical lens-based systems. These characteristics make the proposed topology suitable for applications in laptop computers, tablets PC's, PDAs, flat screen TVs and similar products.