Broadband low cost beam-steering techniques for wireless applications

We have developed low-cost beam steering techniques which do not use conventional ferrite or solid-state phase shifters. These new techniques have many advantages including low cost, broad bandwidth, low loss, wide scan angle, and simplicity. One method uses an aperture-coupled microstrip patch antenna array fed by a dielectric image line with a movable reflector plate (DILWRP). In another concept, a phased array incorporates a multi-line configuration with progressive phase shifts controlled by PET (piezoelectric transducer). Bidirectional beam steering is demonstrated from 7.6 to 26.5 GHz with a maximum beam scanning range from -34/spl deg/ to +26/spl deg/. The third technique employs a scanning antenna using a movable grating array to form a leaky wave antenna. It achieves the following results: 32/spl deg/ scanning at 30 GHz, 53/spl deg/ at 35 GHz, and 35/spl deg/ at 40 GHz. The measurement results agree very well with the predictions.