RFID transmitter
First Claim
1. A transmitter comprising:
- a resonant circuit including at least one capacitor; and
a driver coupled to drive said resonant circuit,wherein said resonant circuit includes a resonance regeneration system configured to modulate an amplitude of a resonant signal in said resonant circuit such that (a) when an amplitude of said resonant signal is reduced by the resonance regeneration system, energy is stored in the at least one capacitor and (b) when said amplitude is increased by the resonance regeneration system, the energy stored in the at least one capacitor is used to regenerate said resonance signal.
2 Assignments
0 Petitions
Accused Products
Abstract
Embodiments of the invention relate to the field of RFID interrogators, particularly RFID interrogators that combine low loss with high rates of communication from the interrogator to a tag. Further embodiments relate to the field of active RFID tags and general radio transmitters. We describe a transmitter comprising a resonant circuit and a driver coupled to drive said resonant circuit, wherein said resonant circuit includes a resonance regeneration system such that during amplitude modulation of a resonant signal in said resonant circuit when an amplitude of said resonant signal is reduced energy from said reduction is stored and when said amplitude is increased said stored energy is used to regenerate said resonance signal.
15 Citations
20 Claims
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1. A transmitter comprising:
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a resonant circuit including at least one capacitor; and a driver coupled to drive said resonant circuit, wherein said resonant circuit includes a resonance regeneration system configured to modulate an amplitude of a resonant signal in said resonant circuit such that (a) when an amplitude of said resonant signal is reduced by the resonance regeneration system, energy is stored in the at least one capacitor and (b) when said amplitude is increased by the resonance regeneration system, the energy stored in the at least one capacitor is used to regenerate said resonance signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
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- 15. A transmitter comprising a resonant circuit including an antenna, the resonant circuit comprising at least a capacitor, and FET switch coupled in series with said capacitor, and a signal generator synchronized to a resonant signal when the resonant signal oscillates in said resonant circuit, wherein said signal generator is configured to control said FET switch, and wherein the circuit further comprises a controller to stop said signal generator to stop oscillation of said resonant signal in said resonant circuit at the off cycle of an amplitude modulation of the resonant circuit.
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18. A transmitter comprising a system for switching a resonant oscillation on and off in a resonant circuit using a switch coupled in series with said resonant circuit, the system further comprising:
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means for driving said resonant circuit with a stimulus; means for determining a relative timing between said stimulus and an output current from said resonant circuit; means for switching said oscillator off using said switch and for stopping said stimulus; and means for switching said oscillation on and for restarting said stimulus, said means for switching said oscillation on and for restarting said stimulus being configured to use said determined relative timing to control a relative timing between switching said resonant oscillation on and said stimulus restarting. - View Dependent Claims (19, 20)
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Specification