US5374930A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High speed read/write AVI system
Assignee: Texas Instruments Inc
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Filing: 1993-11-12
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Granted: 1994-12-20
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Expires: 2013-11-12
Abstract
Abstract A transponder (14) for communicating with an interrogator (12) has a high Q-factor resonant circuit (34) of frequency f1 for receiving RF powering signals. The transponder also has a tuning circuit (56,58) which when in electrical communication with the resonant circuit (34) is operable to form a lower Q-factor resonant circuit (60) of frequency f3 for receiving RF communications from the interrogator unit. The transponder also includes a demodulator (66) which is in electrical communication with said resonant circuit (34). Additionally, the transponder (14) also included a control circuit (40) which receives a demodulated data signal from the demodulator (66). The control circuit (40) is further connected to the tuning circuit (56,58) and is operable to connect the tuning circuit (56,58) to the high Q-factor resonant circuit (34) in order to form the lower Q-factor resonant circuit (60). Control circuit (40) also converts the RF powering signals to a DC current for storing energy. The energy is stored in an energy storage device such as a storage capacitor (46). Other devices, methods and systems are disclosed.
Inventors
- 👤 Josef H. Schuermann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:51
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/74; G01S13/75; G01S13/751; G01S13/758; G06; G06K; G06K19/00; G06K19/06; G06K19/067; G06K19/07; G06K19/0723; G06K7/00; G06K7/0008
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
108 words
A method of communicating between an interrogator and a transponder, the method comprising: a) sending RF powering signals of frequency f 1 from said interrogator to said transponder; b) receiving said RF powering signals in a resonant circuit of said transponder, said resonant circuit having a resonant frequency of approximately f 1 ; c) controlling a tuning circuit in electrical communication with said resonant circuit to change the resonant frequency of said resonant circuit to approximately f 3 ; d) sending RF communications from said interrogator, said RF communications having a carrier frequency of approximately f 3 ; and e) receiving by said resonant circuit said RF communications.
Claim 2
Independent Claim
108 words
A method of communicating between an interrogator and a transponder, the method comprising: a) sending RF powering signals of frequency f 1 from said interrogator to said transponder; b) receiving said RF powering signals in a resonant circuit of said transponder, said resonant circuit having a resonant frequency of approximately f 1 ; c) controlling a tuning circuit in electrical communication with said resonant circuit to change the resonant frequency of said resonant circuit to approximately f 3 ; d) sending RF communications from said interrogator, said RF communications having a carrier frequency of approximately f 3 ; and e) receiving by said resonant circuit said RF communications.
Claim 3
Dependent Claim
14 words
The method of claim 1 wherein said resonant circuit initially has a high Q-factor.
Claim 4
Dependent Claim
20 words
The method of claim 2 wherein said tuning circuit is further operable to lower the Q-factor of said resonant circuit.
Claim 5
Dependent Claim
28 words
The method of claim 1 and further comprising the step of controlling said tuning circuit to return the resonant frequency of said resonant circuit to f 1 .
Claim 6
Dependent Claim
17 words
The method of claim 1 and further comprising the step of writing data to a transponder memory.
Claim 7
Dependent Claim
21 words
The method of claim 1 and further comprising the step of sending responsive RF communications from said transponder to said interrogator.
Claim 8
Dependent Claim
29 words
The method of claim 6 and further comprising the step of modulating continued oscillations in said transponder resonant circuit with data provided to a modulator from a transponder memory.
Claim 9
Dependent Claim
27 words
The method of claim 1 wherein said tuning circuit comprises a damping resistor for lowering the Q-factor of said resonant circuit in combination with said tuning circuit.
Claim 10
Dependent Claim
25 words
The method of claim 1 wherein said RF communications are made by transmitting an FSK-modulated signal having a center frequency of approximately f 3 .
Claim 11
Dependent Claim
18 words
The method of claim 10 and further comprising the step of demodulating said FSK-modulated signal in said interrogator.
Claim 12
Independent Claim
127 words
A method of communicating between an interrogator and a transponder, the method comprising: a) sending RF powering signals of frequency f 1 from said interrogator to said transponder; b) receiving said RF powering signals in a resonant circuit of said transponder, said resonant circuit having a high Q-factor and a resonant frequency of approximately f 1 ; c) electrically connecting a tuning circuit to said resonant circuit thereby changing the resonant frequency of said resonant circuit to approximately f 3 ; d) sending RF communications from said interrogator, said RF communications having a carrier frequency of approximately f 3 ; e) receiving by said resonant circuit said RF communications; and f) sending responsive RF communications from said transponder to said interrogator in response to said RF communications.
Claim 13
Independent Claim
127 words
A method of communicating between an interrogator and a transponder, the method comprising: a) sending RF powering signals of frequency f 1 from said interrogator to said transponder; b) receiving said RF powering signals in a resonant circuit of said transponder, said resonant circuit having a high Q-factor and a resonant frequency of approximately f 1 ; c) electrically connecting a tuning circuit to said resonant circuit thereby changing the resonant frequency of said resonant circuit to approximately f 3 ; d) sending RF communications from said interrogator, said RF communications having a carrier frequency of approximately f 3 ; e) receiving by said resonant circuit said RF communications; and f) sending responsive RF communications from said transponder to said interrogator in response to said RF communications.
Claim 14
Dependent Claim
20 words
The method of claim 11 wherein said tuning circuit is further operable to lower the Q-factor of said resonant circuit.
Claim 15
Dependent Claim
35 words
The method of claim 11 and further comprising the step of modulating continued oscillations in said transponder resonant circuit with data provided to a modulator from a transponder memory to form said responsive RF communications.
Claim 16
Dependent Claim
25 words
The method of claim 13 wherein said RF communications are made by transmitting an FSK-modulated signal having a center frequency of approximately f 3 .
Claim 17
Independent Claim
167 words
A method of communicating between an interrogator and a transponder, the method comprising: a) sending RF powering signals of frequency, f 1 , from an interrogator to a transponder; b) storing the energy received in said powering signals in an energy storage device; c) receiving by a high Q-factor resonant circuit of said transponder said RF powering signals, said transponder resonant circuit having a resonant frequency of approximately f 1 ; d) connecting a tuning circuit to said resonant circuit, said tuning circuit operable to lower the Q-factor of said transponder resonant circuit and to change the frequency of said transponder resonant circuit to approximately f 3 ; e) sending an FSK-modulated RF communication from said interrogator to said transponder, said FSK modulation having a center frequency of approximately f 3 ; f) receiving in said transponder resonant circuit said FSK-modulated RF communication; g) demodulating in said transponder said FSK-modulated RF communication; h) responding by said transponder to said RF communication by sending an FSK-modulated RF response.
Claim 18
Independent Claim
167 words
A method of communicating between an interrogator and a transponder, the method comprising: a) sending RF powering signals of frequency, f 1 , from an interrogator to a transponder; b) storing the energy received in said powering signals in an energy storage device; c) receiving by a high Q-factor resonant circuit of said transponder said RF powering signals, said transponder resonant circuit having a resonant frequency of approximately f 1 ; d) connecting a tuning circuit to said resonant circuit, said tuning circuit operable to lower the Q-factor of said transponder resonant circuit and to change the frequency of said transponder resonant circuit to approximately f 3 ; e) sending an FSK-modulated RF communication from said interrogator to said transponder, said FSK modulation having a center frequency of approximately f 3 ; f) receiving in said transponder resonant circuit said FSK-modulated RF communication; g) demodulating in said transponder said FSK-modulated RF communication; h) responding by said transponder to said RF communication by sending an FSK-modulated RF response.
Claim 19
Dependent Claim
183 words
A high speed RFID system, the system comprising: a) an interrogator for communicating with a transponder, said interrogator having i) a programmable carrier wave generator capable of providing a carrier of a powering frequency, f 1 , and of a communicating frequency, f 3 , and ii) a modulator for modulating data upon said carrier at said communicating frequency, f 3 ; and b) a transponder for communicating with an interrogator, said transponder having i) a high Q-factor resonant circuit having a resonant frequency of approximately said powering frequency, f 1 , ii) a tuning circuit which is operable to lower the Q-factor of said resonant circuit and to change the resonant frequency of said resonant circuit to approximately f 3 , iii) a control circuit which is in electrical communication with said high Q-factor resonant circuit and said tuning circuit and is operable to connect said tuning circuit to said high Q-factor resonant circuit in order to form said lower Q-factor resonant circuit, and iv) an energy storage device for storing the energy received in said DC current from said control circuit.
Claim 20
Dependent Claim
183 words
A high speed RFID system, the system comprising: a) an interrogator for communicating with a transponder, said interrogator having i) a programmable carrier wave generator capable of providing a carrier of a powering frequency, f 1 , and of a communicating frequency, f 3 , and ii) a modulator for modulating data upon said carrier at said communicating frequency, f 3 ; and b) a transponder for communicating with an interrogator, said transponder having i) a high Q-factor resonant circuit having a resonant frequency of approximately said powering frequency, f 1 , ii) a tuning circuit which is operable to lower the Q-factor of said resonant circuit and to change the resonant frequency of said resonant circuit to approximately f 3 , iii) a control circuit which is in electrical communication with said high Q-factor resonant circuit and said tuning circuit and is operable to connect said tuning circuit to said high Q-factor resonant circuit in order to form said lower Q-factor resonant circuit, and iv) an energy storage device for storing the energy received in said DC current from said control circuit.
Claim 21
Dependent Claim
27 words
The system of claim 16 wherein said transponder further comprises a modulator for modulating data upon a carrier signal oscillating in the resonant circuit of said transponder.
Claim 22
Dependent Claim
30 words
The system of claim 17 wherein said modulator modulates said data by frequency shift keying said carrier frequency, said frequency shift keying being centered about communicating frequency, f 3 .
Claim 23
Dependent Claim
26 words
The system of claim 17 wherein powering frequency f 1 is also one of the frequency shift keying frequencies centered about communicating frequency, f 3 .
Claim 24
Dependent Claim
44 words
The system of claim 17 wherein said programmable carrier wave generator comprises a carrier wave generator and a programmable divider whereby said powering and said communicating frequencies are generated by said programmable divider as submultiples of a reference carrier under direction from said modulator.
References Cited (Backward Citations)
US5287112A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-12-19 | 1998-06-20 | 1998-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-12-19 | 2002-06-20 | 2002-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-12-19 | 2006-06-20 | 2006-12-20 | $7700.00 | Window Closed / Lapsed |