A Simple Vector Control Unit for Low Cost Active Reflectarray Applications
نویسندگان
چکیده
In this paper, a one quadrant simultaneous phase/gain control is proposed as a basic unit of an active reflectarray. Perpendicular polarizations in a square patch have been employed for receiving and retransmitting the signal. Its desired phase and gain values have been obtained by means of an adequate biasing of two in quadrature amplifying branches. As an adequate linearity must be assured in an active reflectarray, the intermodulation distortion of the unit has been studied when the PHEMT based amplifiers are biased in a classical way. Finally, a new biasing technique has been employed in order to assure low distortion and better efficiency in all phase and gain values of the retransmitted signal.
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