2.45 GHz telecontrol for cross-band biomedical radio transponder application

The paper discusses the design of a minimum power 2.45 GHz pulse receiver and companion transmitter for use in a semi active, duplex RF transponder. A 50 /spl Omega/ microstrip stub matched zero bias diode detector forms the heart of the body-worn receiver, achieving a tangential sensitivity of -56 dBm. Three-pole bandpass filtering provides rejection of out of band signals, typically 28 dB in the 900 MHz cellular band. A 3.6 V portable on-off-keyed transmitter with suitable output power to communicate with the transponder provided a full mobile transmitter for system tests.