Peer to peer ranging exchange

• US 10,225,338 B1
• Filed: 04/15/2015
• Issued: 03/05/2019
• Est. Priority Date: 04/15/2014
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell International Limited (Marvell Technology Group Limited)
• Inventors: Chu, Liwen, Tamhane, Sagar, Wagholikar, Sarang Shrikrishna, Zhang, Hongyuan, Lou, Hui-Ling
• Primary Examiner(s): Lazaro, David R
• Application Number:
  US14/687,705
• Time in Patent Office: 1,420 Days
• CPC Class Codes: G01S 5/0289 of multiple transceivers, e.g. in ad hoc networks
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 67/1042 using topology management mechanisms
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others
• CPC Class Codes: H04W 56/007 Open loop measurement
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A method for discovering devices in a peer to peer (P2P) wireless communication network is described. During a search state of a first communication device, a probe request is transmitted by the first communication device on a first channel included in a plurality of channels. During the search state, a probe response transmitted by a second communication device on the first channel is received by the first communication device. In response to the probe response, a ranging exchange with the second communication device is performed by the first communication device.

Claims

1. A method for discovering devices in a peer to peer (P2P) wireless communication network, the method comprising:

during a search state of a first communication device, transmitting, by the first communication device, a first probe request on a first channel included in a plurality of channels, wherein the search state (i) is one of a plurality of different states in which the first communication device is configured to operate, and (ii) corresponds to a contiguous time period in which the first communication device is configured to transmit multiple probe requests on different channels among the plurality of channels;

during the search state, receiving, by the first communication device, a first probe response transmitted by a second communication device on the first channel;

in response to receiving the first probe response, performing, by the first communication device, a ranging exchange with the second communication device;

during an advertise state of the first communication device, listening, by the first communication device, for probe requests on a second channel included in the plurality of channels, wherein the advertise state corresponds to another contiguous time period in which the first communication device is configured to listen for probe requests on a single channel, and wherein a duration of the other contiguous time period is randomly or pseudo-randomly determined by the first communication device;

during the advertise state, transmitting, by the first communication device, a second probe response to a second probe request transmitted by a third communication device on the second channel if the second probe request is received on the second channel during the advertise state;

during the advertise state and in response to the second probe request, listening, by the first communication device, for probe requests on the second channel and for a ranging request transmitted by the third communication device; and

during the advertise state and in response to the ranging request

transmitting, by the first communication device, a first action frame having a dialog token for a fine timing measurement exchange, and

storing, by the first communication device, a first departure time indicator for the first action frame.

2. The method of claim 1, wherein the first communication device performs the ranging exchange without first joining a P2P group with the second communication device.

3. The method of claim 1, wherein performing the ranging exchange comprises performing the ranging exchange during the search state of the first communication device on the first channel.

4. The method of claim 3, further comprising maintaining, by the first communication device, the search state of the first communication device on the first channel until an end of the ranging exchange.

5. The method of claim 1, further comprising:

determining, by the first communication device, whether the second communication device is within a threshold range based on the ranging exchange; and

in response to a determination that the second communication device is within the threshold range, performing, by the first communication device, a group formation procedure to form a P2P group with the second communication device.

6. The method of claim 5, wherein performing the ranging exchange comprises:

transmitting, by the first communication device, a ranging request to the second communication device;

storing, by the first communication device, a first arrival time indicator that corresponds to a second action frame transmitted by the second communication device in response to the ranging request transmitted by the first communication device;

transmitting, by the first communication device, an acknowledgment to the second action frame;

storing, by the first communication device, a second departure time indicator for the acknowledgement to the second action frame; and

in response to a third action frame transmitted by the second communication device, estimating, by the first communication device, a round trip time between the first communication device and the second communication device based on i) the first arrival time indicator, ii) a third departure time indicator that corresponds to the second action frame, iii) a second arrival time indicator that corresponds to the acknowledgment to the second action frame, and iv) the second departure time indicator, the third action frame including the third departure time indicator and the second arrival time indicator.

7. The method of claim 6, wherein:

the first arrival time indicator has a value T2, the third departure time indicator has a value T1, the second arrival time indicator has a value T4, and the second departure time indicator has a value T3, and

estimating the round trip time comprises determining the round trip time as;

(T4−

T1)−

(T3−

T2).

8. The method of claim 6, wherein performing the ranging exchange comprises setting a reference time for the ranging exchange based on a timing synchronization function value that corresponds to the first probe response.

9. The method of claim 1, further comprising:

during the advertise state and in response to an acknowledgment to the first action frame transmitted by the third communication device, transmitting, by the first communication device, a second action frame that indicates the first departure time indicator for the first action frame and an arrival time indicator of the acknowledgment of the first action frame.

10. The method of claim 1, wherein:

the ranging request includes one or more timing parameters for the ranging exchange; and

transmitting the first action frame comprises;

modifying at least one of the one or more timing parameters to avoid absence periods of the first communication device, and

transmitting the first action frame using the one or more timing parameters including the at least one modified timing parameter.

11. The method of claim 10, wherein modifying the at least one of the one or more timing parameters comprises modifying a start time of the one or more timing parameters to avoid the absence periods.

12. The method of claim 10, wherein modifying the at least one of the one or more timing parameters comprises modifying an action frame interval of the one or more timing parameters to avoid the absence periods.

13. A first communication device, comprising:

a network interface device configured to;

during a search state of a first communication device, transmit a first probe request on a first channel included in a plurality of channels, wherein the search state (i) is one of a plurality of different states in which the first communication device is configured to operate, and (ii) corresponds to a contiguous time period in which the first communication device is configured to transmit multiple probe requests on different channels among the plurality of channels,

during the search state, receive a first probe response transmitted by a second communication device on the first channel,

in response to the received first probe response, perform a ranging exchange with the second communication device,

during an advertise state of the first communication device, listen for probe requests on a second channel included in the plurality of channels, wherein the advertise state corresponds to another contiguous time period in which the first communication device is configured to listen for probe requests on a single channel, and wherein a duration of the other contiguous time period is randomly or pseudo-randomly determined by the first communication device,

during the advertise state, transmit a second probe response to a second probe request transmitted by a third communication device on the second channel if the second probe request is received on the second channel during the advertise state,

during the advertise state and in response to the second probe request, listen for probe requests on the second channel and for a ranging request transmitted by the third communication device, and

during the advertise state and in response to the ranging request

i) transmit a first action frame having a dialog token for a fine timing measurement exchange, and

ii) store a first departure time indicator for the first action frame.

14. The first communication device of claim 13, wherein the network interface device is configured to:

perform the ranging exchange without first joining a peer-to-peer group with the second communication device.

15. The first communication device of claim 13, wherein the network interface device is configured to:

perform the ranging exchange during the search state of the first communication device on the first channel.

16. The first communication device of claim 15, wherein the network interface device is further configured to:

maintain the search state of the first communication device on the first channel until an end of the ranging exchange.

17. The first communication device of claim 13, wherein the network interface device is further configured to:

determine whether the second communication device is within a threshold range based on the ranging exchange; and

in response to a determination that the second communication device is within the threshold range, perform a group formation procedure to form a peer-to-peer (P2P) group with the second communication device.

18. The first communication device of claim 13, wherein the network interface device is further configured to:

during the advertise state and in response to an acknowledgment to the first action frame transmitted by the third communication device, transmit a second action frame that indicates the first departure time indicator for the first action frame and an arrival time indicator of the acknowledgment of the first action frame.

19. The first communication device of claim 13, wherein:

the ranging request includes one or more timing parameters for the ranging exchange; and

the network interface device is configured to

modify at least one of the one or more timing parameters to avoid absence periods of the first communication device, and

transmit the first action frame using the one or more timing parameters including the at least one modified timing parameter.

20. The first communication device of claim 19, wherein the network interface device is configured to modify a start time of the one or more timing parameters to avoid the absence periods.

21. The first communication device of claim 19, wherein the network interface device is configured to modify an action frame interval of the one or more timing parameters to avoid the absence periods.