Communication devices having controlled impedances
First Claim
1. A communications device, comprising;
- a controlled impedance; and
a controller configured to vary the controlled impedance upon startup of the communications device to dynamically control a magnetic field strength of a magnetic field of a radio frequency signal.
4 Assignments
0 Petitions
Accused Products
Abstract
A NFC communications enabled device has a data store to store data, an inductive coupler to couple inductively with the magnetic field of a radio frequency signal and a signal supplier to supply a radio frequency signal to the inductive coupler. A modulator modulates a radio frequency signal in accordance with data and a demodulator extracts data from a modulated radio frequency signal inductively coupled to the coupler. A controller enables the NFC communications enabled device both to initiate near field radio frequency communication with another near field RF communicator and to respond to near field radio frequency communication initiated by another near field RF communicator. The inductive coupler has an antenna and a variable impedance element. The controller is configured to control the variable impedance element to control a magnetic field strength associated with a radio frequency signal supplied by the signal supplier.
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Citations
20 Claims
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1. A communications device, comprising;
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a controlled impedance; and a controller configured to vary the controlled impedance upon startup of the communications device to dynamically control a magnetic field strength of a magnetic field of a radio frequency signal. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A communications device, comprising:
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a controlled impedance; and a controller configured to dynamically vary the controlled impedance when a protocol associated with the communications device changes to dynamically control a magnetic field strength of a magnetic field of a radio frequency signal. - View Dependent Claims (9, 10, 11, 12, 13, 14)
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15. A method of operating a communications device, comprising:
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receiving a magnetic field that is associated with a radio frequency signal; and dynamically varying a controlled impedance to dynamically control a magnetic field strength of the magnetic field when a protocol associated with the magnetic field changes. - View Dependent Claims (16, 17, 18, 19, 20)
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Specification