Signal transceiver

• US 20030090366A1
• Filed: 08/28/2002
• Published: 05/15/2003
• Est. Priority Date: 11/09/2001
• Status: Active Grant

• Current Assignee: Holtek Semiconductor Incorporated
• Original Assignee: Holtek Semiconductor Incorporated
• Inventors: Hsieh, Ian, Tsai, Jason
• Granted Patent: US 6,915,108 B2
• Time in Patent Office: Days
• US Class Current: 340/10.1
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer

Abstract

A signal transceiver for transmitting a carrier signal to a transponder and receiving a modulated data signal returned by the transponder is provided. The signal transceiver includes a transistor with a base, a collector and an emitter, a controller being electrically connected to the base and providing a controlling signal for turning on the transistor, an oscillation source being electrically connected to the collector for providing the carrier signal, a capacitor being electrically connected to the base and the oscillation source for forming an oscillation circuit, and a resonator being electrically connected to the collector for transmitting the carrier signal to the transponder and receiving the modulated data signal returned by the transponder, and outputting a demodulated data signal through the emitter.

Claims

1. A signal transceiver for transmitting a carrier signal to a transponder and receiving a modulated data signal returned by said transponder, comprising:

a transistor with a base, a collector and an emitter;

a controller being electrically connected to said base and providing a controlling signal for turning on said transistor;

an oscillation source being electrically connected to said collector for providing said carrier signal;

a capacitor being electrically connected to said base and said oscillation source for forming an oscillation circuit; and

a resonator being electrically connected to said collector for transmitting said carrier signal to said transponder and receiving said modulated data signal returned by said transponder, and outputting a demodulated data signal through said emitter.

2. The signal transceiver according to claim 1 wherein said controller is a micro-controller.

3. The signal transceiver according to claim 1 wherein said controller is a voltage divider.

4. The signal transceiver according to claim 3 wherein said voltage divider is a series of resistors including at least two resistors.

5. The signal transceiver according to claim 1 wherein said oscillation source is a quartz oscillator.

6. The signal transceiver according to claim 1 wherein said resonator is an inductance-capacitance resonant circuit.

7. The signal transceiver according to claim 1 wherein said modulated data signal is modulated by amplitude-shift keying (ASK).

8. The signal transceiver according to claim 1 wherein said demodulated data signal is an envelope signal.

9. A signal transceiver for transmitting a carrier signal to a transponder and receiving a modulated data signal returned by said transponder, comprising:

a transistor with a base, a collector and an emitter;

a controller being electrically connected to said base and providing a controlling signal for turning on said transistor;

an oscillator being electrically connected to said base for providing an oscillation frequency for said carrier signal; and

a resonator being electrically connected to said collector for transmitting said carrier signal to said transponder and receiving said modulated data signal returned by said transponder, and outputting a demodulated data signal through said emitter.

10. The signal transceiver according to claim 9 wherein said controller is a micro-controller.

11. The signal transceiver according to claim 9 wherein said controller is a voltage divider.

12. The signal transceiver according to claim 11 wherein said voltage divider is a series of resistors including at least two resistors.

13. The signal transceiver according to claim 9 wherein said resonator is an inductance-capacitance resonant circuit.

14. The signal transceiver according to claim 9 wherein said modulated data signal is modulated by amplitude-shift keying (ASK).

15. The signal transceiver according to claim 9 wherein said demodulated data signal is an envelope signal.