DC power pattern of rectifier-antennas

This paper addresses calculations and a measurement procedure for rectifier-antenna DC power patterns. The pattern of a rectifier-antenna is dependent on the antenna gain G(θ,φ) and the rectifier efficiency η_RF-DC. This makes the pattern dependent not only on the angles θ and φ but also on frequency, RF input power to the rectifier (P_{RF, in}) and the DC load (R_L). Example of a 1.96GHz patch rectifier-antenna is presented in the paper. It is shown that measured patterns of the integrated rectifier-antenna match theoretical predictions at incident power density levels form 25-200μW/cm².