Automatic antenna tuner system for RFID
First Claim
1. An automatic antenna tuning system comprising:
- (a) a pulse width modulator;
(b) a microprocessor for controlling the generation of frequency of a source signal from said modulator;
(c) an inductor;
(d) a plurality of relay contacts and capacitors for receiving said source signal from said amplifiers and transmitting it to said inductor, said inductor, and capacitor generating a resonating signal;
(e) a gate communicating with said capacitors through one or more relay contacts for transmitting said resonating signal as a carrier signal;
(f) means for gating said carrier signal with said source signal to produce a compared signal for gating with a crystal to produce a string of pulses, said microprocessor having a (i) counter for determining the count of said string of pulses and (ii) means for varying capacitance to increase or decrease the count of said string of pulses.
1 Assignment
0 Petitions
Accused Products
Abstract
An automatic antenna tuner system for radio frequency identification system includes a pulse width modulator, a microprocessor for controlling the generation of a source signal from the modulator, capacitors for receiving the source signal from amplifiers and transmitting it to an inductor, a gate communicating with the capacitors for transmitting a resonating signal from the inductor and capacitors as a carrier signal and means for gating the carrier signal with the source signal to produce a compared signal to produce a string of pulses and means for varying capacitance to increase or decrease the count of the string of pulses.
-
Citations
10 Claims
-
1. An automatic antenna tuning system comprising:
-
(a) a pulse width modulator; (b) a microprocessor for controlling the generation of frequency of a source signal from said modulator; (c) an inductor; (d) a plurality of relay contacts and capacitors for receiving said source signal from said amplifiers and transmitting it to said inductor, said inductor, and capacitor generating a resonating signal; (e) a gate communicating with said capacitors through one or more relay contacts for transmitting said resonating signal as a carrier signal; (f) means for gating said carrier signal with said source signal to produce a compared signal for gating with a crystal to produce a string of pulses, said microprocessor having a (i) counter for determining the count of said string of pulses and (ii) means for varying capacitance to increase or decrease the count of said string of pulses. - View Dependent Claims (2)
-
-
3. An automatic antenna tuning system comprising:
-
(a) a pulse width modulator; (b) a microprocessor for controlling the generation of frequency of a source signal from said modulator; (c) one or more amplifiers for amplifying said source signal; (d) an inductor; (e) a plurality of relay contacts and capacitors for receiving said source signal from said amplifiers and transmitting it to said inductor, said inductor, and capacitor generating a resonating signal; (f) a gate communicating with said capacitors through one or more relay contacts for transmitting said resonating signal as a carrier signal; (g) means for gating said carrier signal with said source signal to produce a compare signal for gating with a crystal to produce a string of pulses, said microprocessor having a (i) counter for determining the count of said string of pulses and (ii) means for varying capacitance to increase or decrease the count of said string of pulses.
-
-
4. A method for tuning an antenna for a radio frequency identification system (RFID) comprising the steps of:
-
(a) emitting a source signal from a pulse width modulator at a frequency; (b) amplifying and transmitting said source signal to a plurality of capacitors and to an inductor, each capacitor having a relay contact; (c) transmitting a signal from said inductor through one or more capacitors to form a carrier signal; (d) gating said carrier signal with said source signal to produce a compared signal; (e) comparing whether said carrier signal is leading or lagging in phase by 90 degrees compared to said source signal; (f) adding or reducing capacitance to vary the count per cycle of said compared signal as needed to establish a 90 degree phase between said carrier signal and said source signal. - View Dependent Claims (5, 6, 7)
-
-
8. A method for tuning an antenna for a radio frequency identification system comprising the steps of:
-
(a) delivering power by means of a source signal to an inductor at a frequency, at a phase; (b) transmitting a resonating signal from said inductor through one or more capacitors to a gate; (c) transmitting a carrier signal from said gate and gating said carrier signal through an AND gate to join with said source signal to produce a compared signal which is gated with a crystal to produce a string of pulses; (d) comparing the phase of the source signal with the phase of the carrier signal; and (e) adding or reducing capacitance to the signal from said inductor if, but only if, the phase difference between the phase of the source signal and the phase of the carrier signal is greater or less than 90 degrees. - View Dependent Claims (9)
-
-
10. A method for controlling inventory of product in a facility comprising the steps of:
-
(a) positioning an antenna and a plurality of RFID transponders in said facility; (b) engaging an antenna tuning system to said antenna, said tuning system including a pulse width modulator and an inductor; (c) transmitting a source signal from said pulse width modulator to a plurality of capacitors and to said inductor, each capacitor having a relay contact; (d) transmitting a signal from said inductor through one or more capacitors to form a carrier signal; (e) gating said carrier signal with said source signal to produce a compared signal; (f) comparing whether said carrier signal is leading or lagging in phase by 90 degrees compared to said source signal; (g) adding or reducing capacitance to vary the count per cycle of said compared signal as needed to establish a 90 degree phase between said carrier signal and said source signal; (h) transmitting a signal from a computer or microprocessor to one or more of said RFID transponders; and (i) transmitting a signal from said one or more RFID transponders to said antenna and said computer.
-
Specification