초록 ▼

A transponder device receives a carrier signal from an interrogator unit. This carrier signal, of frequeny F, is rectified by a rectifying circuit in order to generate operating power. Logic/timing circuits derive a clock signal and second carrier signal of frequency F/n from the received carrier si

A transponder device receives a carrier signal from an interrogator unit. This carrier signal, of frequeny F, is rectified by a rectifying circuit in order to generate operating power. Logic/timing circuits derive a clock signal and second carrier signal of frequency F/n from the received carrier signal. This clock signal reads a unique identifying data word from a programmable read only memory (PROM). The data word is encoded and mixed with the carrier signal in a balanced modulator circuit. The output of the balanced modulator is transmitted to the interrogator unit where it is decoded and used as an identifying signal. The identifying signal identifies the particular transponder device from which it originated. The rectifier and balanced modulator circuits are realized from the same diode elements. All electrical circuits of the transponder device are realized on the same monolithic semiconductor chip. In one embodiment, an antenna receiving/transmitting coil is also part of the chip, being placed around the periphery thereof. In alternative embodiments, various hybrid elements may be connected to the monolithic elements in order to realize additional functions, such as adjustable tuning of the receiving circuit, independent crystal frequency control, and battery-powered operation.

대표청구항 ▼

A transponder device comprising: a single monolithic semiconductor chip; receiving means for receiving a carrier signal from an external source; diode means for rectifying the received carrier signal in order to generate operating power for the transponder device, and for mixing an encoded data word

A transponder device comprising: a single monolithic semiconductor chip; receiving means for receiving a carrier signal from an external source; diode means for rectifying the received carrier signal in order to generate operating power for the transponder device, and for mixing an encoded data word with the carrier signal in order to generate sum and difference signals; digital circuit means for deriving a clock signal from said carrier signal; data generating means responsive to said clock signal for generating the encoded data word that is mixed with the carrier signal in said diode means; and transmitting means for transmitting the sum and difference signals to a location external from said transponder device; said diode means, digital circuit means, and data generating means comprising electrical circuits that are realized on said single monolithic semiconductor chip.