Beam-Steering Antenna Technique Using Operational Amplifiers for Sub-6 GHz

A methodology for beam-steering using operational amplifiers (Op-amps) is presented. Continuous steering is required in various advanced applications and its implementation necessitates additional efforts since singularly control of the feeding of the radiators is mandatory for both phase and amplitude. The present work proposes a technique for generating the required sequence of the feeding signal using two Op-amps for each input port. It leads to generating incremental phases with sequential Op-amps without any limitation in the value of the phase differences, controlled by the bias voltage applied to the Op-amps, hence giving rise to a continuous beam-steering capability. The study case consists of a four-stage oscillator designed for creating a sequence of signals with progressive phase shifts between consecutive outputs. The general scheme allows continuous control of the phase differences here applied for generating a uniform, i.e., constant signal magnitude, feeding sequence. This set of signals is then used to feed a four-element microstrip array operating at 1.2 GHz. The effectiveness of the method is validated by numerical simulation of the array performances. Additionally, the low power consumption of active Op-amps, easy implementation, and high sensitivity are characteristics of the presented paradigm.