US5319802A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for the exchange of data by electromagnetic waves
Assignee: Thomson Composants Microondes
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Filing: 1991-11-15
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Granted: 1994-06-07
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Expires: 2011-11-15
Abstract
Abstract In order to increase the sensitivity and range of a system for the exchange of data by microwaves between a fixed station, or reader, and a mobile station, or badge, the modem of the badge includes an oscillator. A single transistor works, under a first bias, as a detector of the wave transmitted by the reader and demodulates this wave, and then, under a second bias, it works as an oscillator and modulates the response transmitted by the badge. Applications to the exchange of data at a distance.
Inventors
- 👤 Marc Camiade
- 👤 Veronique Serru
- 👤 Dominique Geffroy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 04:47
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/0008; G01; G01S; G01S13/00; G01S13/74; G01S13/76; G01S13/767; G06K19/00; G06K19/06; G06K19/067; G06K19/07; G06K19/0723
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
122 words
A system for the exchange of data by electromagnetic waves between a fixed station and a mobile station, each of said fixed and mobile stations including at least one modulator/demodulator, connected to an antenna for the transmission/reception of said data, wherein at least said mobile station includes a transistor in said at least one modulator/demodulator thereof which, under a first gate bias voltage, works as a detector of a modulated electromagnetic signal transmitted by the fixed station and, under a second gate bias voltage, works as an oscillator for transmitting a modulated electromagnetic signal to said fixed station, wherein the first gate bias voltage corresponds to a low drain current and the second gate bias voltage corresponds to a high drain current.
Claim 2
Independent Claim
122 words
A system for the exchange of data by electromagnetic waves between a fixed station and a mobile station, each of said fixed and mobile stations including at least one modulator/demodulator, connected to an antenna for the transmission/reception of said data, wherein at least said mobile station includes a transistor in said at least one modulator/demodulator thereof which, under a first gate bias voltage, works as a detector of a modulated electromagnetic signal transmitted by the fixed station and, under a second gate bias voltage, works as an oscillator for transmitting a modulated electromagnetic signal to said fixed station, wherein the first gate bias voltage corresponds to a low drain current and the second gate bias voltage corresponds to a high drain current.
Claim 3
Dependent Claim
33 words
A system according to claim 1, wherein the transistor is connected to the antenna by its gate through a matching network, and the source of said transistor is coupled directly to ground potential.
Claim 4
Dependent Claim
22 words
A system according to claim 2, wherein the electromagnetic signal transmitted by the mobile station to the fixed station is amplitude modulated.
Claim 5
Dependent Claim
22 words
A system according to claim 2, wherein the electromagnetic signal transmitted by the mobile station to the fixed station is phase modulated.
Claim 6
Independent Claim
183 words
A system for the exchange of data by electromagnetic waves between a fixed station and a mobile station, each of said fixed and mobile stations including at least one modulator/demodulator connected to an antenna for the transmission/reception of said data, wherein at least said mobile station includes a transistor in said at least one modulator/demodulator thereof which, under a first gate bias voltage, works as a detector of a modulated electromagnetic signal transmitted by the fixed station and, under a second gate bias voltage, works as an oscillator for transmitting a modulated electromagnetic signal to said fixed station, said transistor being connected to the antenna by its gate through a matching network and wherein said mobile station further includes a circuit for processing signals which provide bias voltages to said transistor for switching the transistor between a first position in which the transistor works as the detector and a second position in which the transistor works as the oscillator wherein the first gate bias voltage corresponds to a low drain current and the second gate bias voltage corresponds to a high drain current.
Claim 7
Independent Claim
183 words
A system for the exchange of data by electromagnetic waves between a fixed station and a mobile station, each of said fixed and mobile stations including at least one modulator/demodulator connected to an antenna for the transmission/reception of said data, wherein at least said mobile station includes a transistor in said at least one modulator/demodulator thereof which, under a first gate bias voltage, works as a detector of a modulated electromagnetic signal transmitted by the fixed station and, under a second gate bias voltage, works as an oscillator for transmitting a modulated electromagnetic signal to said fixed station, said transistor being connected to the antenna by its gate through a matching network and wherein said mobile station further includes a circuit for processing signals which provide bias voltages to said transistor for switching the transistor between a first position in which the transistor works as the detector and a second position in which the transistor works as the oscillator wherein the first gate bias voltage corresponds to a low drain current and the second gate bias voltage corresponds to a high drain current.
Claim 8
Dependent Claim
28 words
A system according to claim 1, wherein the electromagnetic waves used between the fixed station and the mobile station are in the range of 1 to 100 GHz.
Claim 9
Dependent Claim
17 words
A system according to claim 1, wherein said mobile station can exchange data with another mobile station.
Claim 10
Independent Claim
20 words
A system according to any of the claims 1 to 7, wherein the mobile station has a "credit card" format.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-06-06 | 1997-12-06 | 1998-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-06-06 | 2001-12-06 | 2002-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-06-06 | 2005-12-06 | 2006-06-07 | $7700.00 | Window Closed / Lapsed |