A Preliminary Study on 24-GHz-Band Fixed-Beam Sweeping Toward Rectenna Array in Wireless-Powered Structural Health Monitoring

A low-cost on-vehicle wireless power transfer system using a fixed beamformer is described. A fixed narrow beam radiated from a beamformer is swept according to the movement of the vehicle., and the passing energy is efficiently received by using a horizontally long-shaped rectenna array. Our simulation results show that the rectenna array achieved the adequate input RF power level to the rectifiers through vertical-element RF combining and aggregates the energy of all rectifier outputs through DC combining. The wireless power transfer system that we propose can provide a required amount of energy in a short time., so it is useful for frequency sharing with a low interference probability in addition to minimum spatial spread of reflected waves by the front-direction only radiation.