Short-range wireless communication

• US 8,989,669 B2
• Filed: 10/25/2013
• Issued: 03/24/2015
• Est. Priority Date: 06/16/2008
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell World Trade Limited (Marvell Technology Group Limited)
• Inventors: Banerjea, Raja
• Primary Examiner(s): Hanidu, Ganiyu A
• Application Number:
  US14/063,972
• Publication Number:
  US 20140073251A1
• Time in Patent Office: 515 Days
• Field of Search: 455/41.2, 455/522, 455/24, 455/453, 455/69, 455/126, 455/115.1, 455/67.11, 455/13.4, 370/335, 370/437, 370/338
• US Class Current: 455/41.2
• CPC Class Codes: H04W 52/245 taking into account received signal strength
• CPC Class Codes: H04W 52/38 TPC being performed in particular situations
• CPC Class Codes: H04W 52/383 power control in peer-to-peer links
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 76/14 Direct-mode setup

Abstract

The present specification describes techniques and apparatus that enable wireless devices to communicate effectively at short ranges. In one implementation, the transmit power of a transmitting device is reduced to permit a receiving device to demodulate a signal.

Claims

1. A method for wireless communication, the method comprising:

receiving, via a receiver of a device, a link-setup request through a wireless network from another device, the link-setup request requesting a current transmit-power of a transmitter of the device and received at a power level insufficient to saturate the receiver of the device;

transmitting, via the transmitter of the device, a link-setup response through the wireless network to the other device, the link-setup response indicating the current transmit-power of the transmitter;

receiving, via the receiver of the device and in response to the link-setup response, an indication of a desired data-signal transmit-power through the wireless network from the other device, the indication of a desired data-signal transmit-power indicating a desired transmit-power at which data-signals are to be transmitted from the device; and

transmitting, via the transmitter, the data-signals through the wireless network to the other device at the desired data-signal transmit-power.

2. The method as recited in claim 1, wherein the link-setup request, the link-setup response, or indication of the desired data-signal transmit-power are modulated using a first modulation scheme, and the data-signals transmitted to the other device are modulated using a second modulation scheme.

3. The method as recited in claim 2, wherein each of the link-setup request, the link-setup response, and the indication of the desired data-signal transmit-power are modulated using the first modulation scheme.

4. The method as recited in claim 2, wherein the first modulation scheme is a direct-sequence spread spectrum (DSSS) modulation scheme.

5. The method as recited in claim 2, wherein the second modulation scheme is an orthogonal frequency division multiplex (OFDM) modulation scheme or a complimentary code keying (CCK) modulation scheme.

6. The method as recited in claim 1, wherein a distance over which the device is communicating with the other device is approximately 0.2 meters or less.

7. The method as recited in claim 1, wherein the wireless network is a wireless personal-area-network implemented in accordance with a short-range radio communication protocol.

8. One or more non-transitory computer-readable memory devices

comprising processor-executable instructions, that responsive to execution by a processor, implement a wireless communicator configured to:

transmit, via a transmitter of a device, an indication of a current transmit-power through a wireless network to another device, the indication of a current transmit-power indicating a current transmit-power of the transmitter and modulated using a first modulation scheme;

receive, via a receiver of the device and in response to the indication of a current transmit-power, an indication of a desired transmit-power through the wireless network from the other device, the indication of a desired transmit-power modulated using the first modulation scheme and indicating a desired transmit-power at which data-signals modulated using a second modulation scheme are to be transmitted; and

transmit, via the transmitter and at the desired transmit-power, the data-signals modulated using the second modulation scheme through the wireless network to the other device.

9. The one or more computer-readable memory devices as recited in claim 8, comprising additional processor-executable instructions, that responsive to execution by the processor, implement the wireless communicator to receive, via the receiver of the device, a transmit-power request through the wireless network from the other device, the transmit-power request requesting the current transmit-power of the transmitter and received at a power level insufficient to saturate the receiver of the device.

10. The one or more computer-readable memory devices as recited in claim 9, wherein the transmit-power request received from the other device is a link-setup request and the indication of the current transmit-power transmitted to the other device is a link-setup response.

11. The one or more computer-readable memory devices as recited in claim 9, wherein the transmit-power request is modulated using the first modulation scheme.

12. The one or more computer-readable memory devices as recited in claim 8, wherein the first modulation scheme is a direct-sequence spread spectrum (DSSS) modulation scheme.

13. The one or more computer-readable memory devices as recited in claim 8, wherein the second modulation scheme is an orthogonal frequency division multiplex (OFDM) modulation scheme or a complimentary code keying (CCK) modulation scheme.

14. The one or more computer-readable memory devices as recited in claim 8, wherein the wireless network is a wireless personal-area-network implemented in accordance with a short-range radio communication protocol.

15. A System-on-Chip comprising:

an interface to a receiver configured to receive data via a wireless medium, the interface to the receiver implemented at least partially in hardware;

an interface to a transmitter configured to transmit data via the wireless medium, the interface to the transmitted implemented at least partially in hardware; and

one or more processors configured to execute processor-executable instructions that, responsive to execution, implement a wireless communicator configured to;

receive, via the receiver, a link-setup request through the wireless medium from a device, the link-setup request requesting a current transmit-power of the transmitter and received at a power level insufficient to saturate the receiver;

transmit, via the transmitter, a link-setup response through the wireless medium to the device, the link-setup response indicating the current transmit-power of the transmitter;

receive, via the receiver and in response to the link-setup response, an indication of a desired data-signal transmit-power through the wireless medium from the device, the indication of a desired data-signal transmit-power indicating a desired transmit-power at which data-signals are to be transmitted via the transmitter; and

transmit, via the transmitter, the data-signals through the wireless medium to the device at the desired data-signal transmit-power.

16. The System-on-Chip of claim 15, wherein the link-setup request, the link-setup response, or the indication of the desired data-signal transmit-power are modulated using a first modulation scheme, and the data-signals transmitted to the device are modulated using a second modulation scheme.

17. The System-on-Chip of claim 16, wherein the first modulation scheme is a direct-sequence spread spectrum (DSSS) modulation scheme and the second modulation scheme is an orthogonal frequency division multiplex (OFDM) modulation scheme or a complimentary code keying (CCK) modulation scheme.

18. The System-on-Chip of claim 15, wherein the wireless medium is associated with a wireless personal-area-network following an IEEE 802.11-2007 communication protocol.

19. The System-on-Chip of claim 15, wherein receiving the indication of the desired data-signal transmit-power comprises receiving a directed probe response frame from the device.

20. The SoC of claim 15, wherein the System-on-Chip further comprises the receiver configured to receive data via the wireless medium and the transmitter configured to transmit data via the wireless medium.