INFORMATIONSOVERFORINGSANORDNING

摘要

An answering device in a system for automatic wireless transmission of an item of information coded by a plurality of frequencies is disclosed herein. An interrogation device movable with respect to the answering device transmits an interrogation signal having a frequency which periodically varies within a predetermined microwave frequency band. The answering device has a plurality of microwave resonators, each of which has a fixed frequency. A microwave diode is coupled to each of the resonators for preventing a response to the interrogation signal by either damping or detuning the resonator fixed frequency when a control voltage is applied. The control voltage means connected to each of the microwave diodes switches certain of the resonators to an inoperative condition to establish a set of frequencies at which the resonators will respond which corresponds to the information to be transmitted.