REVERSE LINK SIGNALING VIA IMPEDANCE MODULATION

• US 20110217926A1
• Filed: 10/15/2010
• Published: 09/08/2011
• Est. Priority Date: 03/03/2010
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Low, Zhen Ning, Estrada, Sergio P.
• Application Number:
  US12/905,938
• Publication Number:
  US 20110217926A1
• Time in Patent Office: Days
• US Class Current: 455/41.1
• CPC Class Codes: H04B 5/26 using coils

Abstract

Exemplary embodiments are directed to reverse-link signaling via modification of an impedance on the receiver as detected by a transmitter. A method may include receiving a signal from a transmitter at a receiver unit. The method may further include adjusting an impedance detectable by the transmitter by modifying a load coupled with the receiver unit.

Claims

1. A method, comprising:

receiving a signal from a transmitter at a receiver unit; and

adjusting an impedance detectable by the transmitter by modifying a load coupled with the receiver unit.

2. The method of claim 1, wherein modifying a load comprises selectively coupling an output of the receiver unit to a ground voltage.

3. The method of claim 1, wherein modifying a load comprises selectively coupling an output of the receiver unit to a ground voltage via at least one of a resistor, a capacitor, and an inductor.

4. The method of claim 3, wherein selectively coupling an output of the receiver unit to a ground voltage comprises selectively coupling the output of the receiver unit to a ground voltage via a transistor.

5. The method of claim 1, wherein modifying a load comprises selectively coupling a node positioned between an output of the receiver unit and an input of a power rectifier to a ground voltage.

6. The method of claim 1, wherein receiving a signal comprises receiving a signal from a transmitter in tune with the receiver unit.

7. A method, comprising:

coupling an output of a receiver unit to a load during a receive state; and

coupling the output of the receiver unit to a voltage, different than the load, during another receive state.

8. The method of claim 7, wherein coupling the output of the receiver unit to a voltage during another receive state comprises coupling the output of the receiver unit to one of a resistor, a capacitor, and an inductor coupled to the voltage.

9. The method of claim 7, wherein coupling an output of a receiver unit to a load comprises coupling the output of the receiver unit to an input of a power rectifier during the receive state.

10. The method of claim 7, wherein coupling the output of the receiver unit to a voltage comprises coupling a node between the output of the receiver unit and an input of a power rectifier to the voltage during the receive state.

11. The method of claim 7, further comprising tuning the receiver unit with an associated transmitter.

12. The method of claim 7, wherein coupling an output of a receiver unit to a voltage comprises causing a transistor coupled between the output of the receiver unit and the voltage to conduct.

13. A receiver, comprising:

a receiver unit configured to receive an RF energy signal; and

a switching circuit coupled to an output of the receiver unit and configured to modify a load coupled with the receiver unit.

14. The receiver of claim 13, wherein the switching circuit comprises a transistor coupled between the output of the receiver unit and a ground voltage.

15. The receiver of claim 14, wherein a drain of the transistor is coupled to each of the output of the receiver unit and the input of a power rectifier.

16. The receiver of claim 14, wherein a source of the transistor is coupled to the ground voltage.

17. The receiver of claim 14, wherein the receive unit comprises a receive coil coupled to a capacitor.

18. The receiver of claim 14, wherein the switching circuit is configured to couple an output of the receiver unit to a power rectifier during a receive state and couple the output of the receiver unit to a ground voltage during another receive state.

19. A device, comprising:

a receiver including a receiver unit; and

a switching element configured to at least one of selectively couple the receiver unit to a load and selectively couple the receiver unit to a ground voltage.

20. The device of claim 19, wherein the switching element is configured to selectively couple the receiver unit to the load during a first phase and selectively couple the receiver unit to a ground voltage during a second phase.

21. The device of claim 19, wherein the switching element is coupled to a resistive component coupled to the ground voltage.

22. The device of claim 19, wherein the switching element comprises a transistor having a drain coupled between the load and the receiver unit and a source coupled to the ground voltage.

23. The device of claim 19, further comprising a power rectifier having an input coupled the switching element.

24. The device of claim 19, wherein the receiver unit further comprises a receive antenna coupled to a capacitor, wherein the transistor is coupled to the capacitor.

25. A device, comprising:

means for receiving a signal from a transmitter at a receiver unit; and

means for adjusting an impedance detectable by the transmitter by modifying a load coupled with the receiver unit.

26. The method of claim 25, wherein the device further comprises means for selectively coupling an output of the receiver unit to a ground voltage.

27. The method of claim 25, wherein the device further comprises means for receiving the signal from a transmitter in tune with the receiving unit.

28. A device, comprising:

means for coupling an output of a receiver unit to a load during a receive state; and

means for coupling the output of the receiver unit to a voltage, different than the load, during another receive state.

29. The method of claim 28, wherein the device further comprises means for coupling a node between the output of the receiver unit and an input of a power rectifier to the ground voltage during the another receive state.

30. The method of claim 28, wherein the device further comprises means for tuning the receiver unit with a transmitter during each of the receive state and the another receive state.