Reconfigurable sub-harmonic mixing antenna for low-cost wireless transceiver applications

A novel reconfigurable frequency translating antenna for cost-effective wireless transceiver applications is described. The integration of a dual transistor sub-harmonic mixing topology with a five-patch series arrangement enables the system to operate in resistive mode for reception or in active mode for transmission. The printed structure behaves as an antenna in the 1850 MHz frequency band and as a stepped-impedance lowpass filter. This avoids undesired radiation of the LO component and allows IF signal extraction in the downconverting mode. Measured isotropic conversion gain (4.47 and 19.3 dB) supports the validity of the proposed solution in low-cost compact wireless transceiver applications.