Methods and apparatuses for communicating in television white space (TVWS) based on TVWS enablement signal

Patent metadata

Field	Value
Publication number	US-9609520-B2
Application number	US-201213349501-A
Country	US
Kind code	B2
Filing date	Jan 12, 2012
Priority date	Jan 14, 2011
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

Certain aspects of the present disclosure relate to techniques for supporting television white space (TVWS) communication. In an aspect of the present disclosure, a low-rate TVWS enabler (Mode II wireless communication device) may provide initial enablement for all Mode I devices (e.g., access points and user terminals), as well as it may transmit a contact verification signal (CVS) on a regular basis to keep the Mode I devices enabled for the TVWS communication.

First claim

The invention claimed is:

1. An apparatus for wireless communications, comprising:
a first circuit configured to search a plurality of channels supporting wireless communication for a signal transmitted from another apparatus on a first channel of the channels, wherein the signal is capable of reaching a plurality of apparatuses for advertising an enablement for the wireless communication;
a second circuit configured to detect, based on the search, the signal and the first channel; and
a transceiver configured to transmit, to the other apparatus upon the detection, a request for the enablement using the first channel.

2. The apparatus of claim 1 , wherein the transceiver is also configured to:
transmit, to the other apparatus, an identifier (ID) of the apparatus along with the request.

3. The apparatus of claim 1 , wherein the plurality of channels supporting wireless communication comprise a plurality of television white space (TVWS) channels supporting TVWS communication, and wherein enablement for the wireless communication comprises enablement for the TVWS communication.

4. The apparatus of claim 3 , wherein the transceiver is also configured to:
receive, in response to the request, at least one of a first list of channels of the plurality of TVWS channels available for use by the apparatus, or a second list of channels of the plurality of TVWS channels being in use by a subset of the apparatuses, and the apparatus further comprising
a third circuit configured to select, from the at least one of first list or second list, a second channel for the TVWS communication by the apparatus.

5. The apparatus of claim 4 , wherein the transceiver is also configured to:
transmit, to the other apparatus, a center frequency and a bandwidth of the second channel.

6. The apparatus of claim 4 , wherein the transceiver is also configured to:
receive, from the other apparatus, a message with information about periodicity of transmitting a contact verification signal (CVS) on the second channel;
receive, with the periodicity, the CVS on the second channel; and
continue the TVWS communication on the second channel based on reception of the CVS.

7. The apparatus of claim 6 , wherein the transceiver is also configured to:
switch from the second channel to the first channel, if the CVS was not received for a period of time; and
transmit, using the first channel, another request for the enablement.

8. The apparatus of claim 6 , wherein the transceiver is also configured to:
transmit, on the second channel according to the periodicity, one or more traffic indication map (TIM) messages and a delivery traffic indication map (DTIM) message before the CVS was transmitted on the second channel from the other apparatus, and wherein
each of the TIM messages comprises a counter that counts down to the transmission of the DTIM message, and
the DTIM message is transmitted immediately before the CVS transmission.

9. The apparatus of claim 6 , wherein the transceiver is also configured to:
transmit, upon receiving the CVS, a broadcast message indicating that the CVS was transmitted from the other apparatus.

10. The apparatus of claim 4 , wherein the transceiver is also configured to:
receive, from the other apparatus, a message comprising a schedule of receiving a contact verification signal (CVS) on the second channel;
refrain, according to the schedule, from the TVWS communication on the second channel;
receive the CVS according to the schedule; and
continue the TVWS communication on the second channel after receiving the CVS.

11. The apparatus of claim 10 , wherein the transceiver is also configured to:
transmit, in response to the message, a broadcast message with the schedule to one or more of the apparatuses associated with the apparatus.

12. The apparatus of claim 10 , wherein the transceiver is also configured to:
transmit a Contention-Free End (CF-End) frame after the CVS was transmitted from the other apparatus.

13. The apparatus of claim 10 , wherein:
the transceiver is also configured to transmit a Clear-to-send (CTS)-to-Self message according to the schedule, and
the CTS-to-Self message comprises a duration field indicating a period of time equal to at least duration of transmitting the CVS from the other apparatus.

14. The apparatus of claim 3 , wherein the transceiver is also configured to:
receive, on the first channel, a message with a schedule of transmitting the signal from the other apparatus, if the first channel is used for the TVWS communication by the apparatus and a subset of the apparatuses; and
refrain from the TVWS communication according to the schedule.

15. The apparatus of claim 14 , wherein the transceiver is also configured to:
transmit, to one or more apparatuses from the subset associated with the apparatus, another message with the schedule.

16. The apparatus of claim 14 , wherein:
the transceiver is also configured to transmit a Clear-to-send (CTS)-to-Self message according to the schedule, and
the CTS-to-Self message comprises a duration field indicating a period of time equal to at least duration of transmitting the signal from the other apparatus.

17. The apparatus of claim 1 , wherein:
the signal comprises a direct sequence spread spectrum (DSSS) signal.

18. The apparatus of claim 1 , wherein:
a data rate of the signal is approximately 10 Kbits per second or 100 Kbits per second, and
a bandwidth of the signal is approximately 5 MHz or 6 MHz.

19. The apparatus of claim 1 , wherein:
a data rate of the signal is approximately 250 Kbits per second, 125 Kbits per second, or 62.5 Kbits per second, and
a bandwidth of the signal is approximately 5 MHz.

20. The apparatus of claim 1 , wherein:
the transceiver is also configured to transmit a beacon comprising information about the first channel, and
the information comprises at least one of a center frequency of the first channel, a bandwidth of the first channel, or an address of the other apparatus.

21. A method for wireless communications, comprising:
searching, at an apparatus, a plurality of channels supporting wireless communication for a signal transmitted from another apparatus on a first channel of the channels, wherein the signal is capable of reaching a plurality of apparatuses for advertising an enablement for the wireless communication;
detecting, based on the search, the signal and the first channel; and
transmitting, to the other apparatus upon the detection, a request for the enablement using the first channel.

22. The method of claim 21 , further comprising:
transmitting, to the other apparatus, an identifier (ID) of the apparatus along with the request.

23. The method of claim 21 , wherein the plurality of channels supporting wireless communication comprise a plurality of television white space (TVWS) channels supporting TVWS communication, and wherein enablement for the wireless communication comprises enablement for the TVWS communication.

24. The method of claim 23 , further comprising:
receiving, in response to the request, at least one of a first list of channels of the plurality of TVWS channels available for use by the apparatus, or a second list of channels of the plurality of TVWS channels being in use by a subset of the apparatuses; and
selecting, from the at least one of first list or second list, a second channel for the TVWS communication by the apparatus.

25.

Assignees

• Shellhammer Stephen J
• Shen Cong
• Tandra Rahul
• Abraham Santosh Paul
• Vermani Sameer
• Sampath Hemanth
• Qualcomm Inc

Inventors

• Shellhammer Stephen J
• Shen Cong
• Tandra Rahul
• Abraham Santosh Paul
• Vermani Sameer
• Sampath Hemanth

Classifications

• H04W84/12

  WLAN [Wireless Local Area Networks] · CPC title

• H04W16/14 Primary

  Spectrum sharing arrangements {between different networks} · CPC title

• H04B1/69

  Spread spectrum techniques · CPC title

• H04L5/0007

  the frequencies being orthogonal, e.g. OFDM(A) or DMT · CPC title

• H04W72/04

  Wireless resource allocation · CPC title