Patent attributes
An electronic device may include first and second phased antenna arrays that convey radio-frequency signals at frequencies greater than 10 GHz. The second array may have fewer antennas than the first array. Control circuitry may control the first and second arrays in a diversity mode and in a simultaneous array mode. In the diversity mode, the first array may form a first signal beam while the second array is inactive. When the first array is blocked by an object or otherwise exhibits unsatisfactory performance, the second array may form a second signal beam while the first array is inactive. In the simultaneous mode, the first and second arrays may form a combined array that produces a third signal beam. The combined array may maximize gain. Hierarchical beam searching operations may be performed. The arrays may be distributed across one or more modules.