Probe Response Suppression Using Angle-Of-Arrival In A High Density Environment

Patent metadata

Field	Value
Publication number	US-2015257117-A1
Application number	US-201414202654-A
Country	US
Kind code	A1
Filing date	Mar 10, 2014
Priority date	Mar 10, 2014
Publication date	Sep 10, 2015
Grant date	—

Abstract

A first wireless device (e.g., an access point) receives a message from a second wireless device (e.g., a client device). The first device determines an angle-of-arrival of the message at a plurality of antennas of the first wireless device. The first device compares the angle-of-arrival with an angle-of-arrival threshold to determine whether to transmit a response message to the second wireless device. In one example, the first wireless device is a wireless access point device operating in a wireless network, the second wireless device is a wireless client device operating in the wireless network, the message is a probe request message and the response message is a probe response message.

First claim

What is claimed is:

1 . A method comprising:
receiving a message at a first wireless device from a second wireless device; determining an angle-of-arrival of the message at a plurality of antennas of the first wireless device; and comparing the angle-of-arrival with an angle-of-arrival threshold to determine whether to transmit a response message to the second wireless device.

2 . The method of claim 1 , further comprising transmitting the response message if the angle-of-arrival is within the angle-of-arrival threshold.

3 . The method of claim 1 , further comprising not transmitting the response message if the angle-of-arrival is not within the angle-of-arrival threshold.

4 . The method of claim 1 , wherein the first wireless device is a first wireless access point device operating in a wireless network, the second wireless device is a wireless client device operating in the wireless network, the message is a probe request message and the response message is a probe response message.

5 . The method of claim 4 , further comprising adjusting the angle-of-arrival threshold.

6 . The method of claim 5 , further comprising receiving a command from a wireless network controller, and wherein adjusting is based on the command.

7 . The method of claim 6 , further comprising determining whether to adjust the angle-of-arrival threshold of the first wireless access point device based on coverage overlap between the first wireless access point device and one or more other wireless access point devices operating in the wireless network.

8 . The method of claim 6 , further comprising determining whether to adjust the angle-of-arrival threshold of the first wireless access point device based on traffic load of the first wireless access point device.

9 . The method of claim 6 , further comprising, at the wireless network controller that is in communication with a plurality of wireless access point devices operating in the wireless network, including the first wireless access point device, adjusting an angle-of-arrival threshold to be used by a group of two or more of the plurality of wireless access point devices.

10 . The method of claim 9 , wherein adjusting comprises dynamically adjusting the angle-of-arrival threshold to be used by the group of two or more of the plurality of wireless access point devices based on conditions in the wireless network.

11 . The method of claim 5 , wherein adjusting is based on signals received by the first wireless access point device from one or more other wireless access point devices operating in the wireless network from which an overlap of coverage of the first wireless access point device can be determined with respect to one or more other wireless access point devices.

12 . An apparatus comprising:
a plurality of antennas; a receiver unit configured to detect signals received at the plurality of antennas; a transmitter configured to transmit a signal via one or more of the plurality of antennas; a modem configured to modulate signals for transmission and to demodulate signals obtained by the receiver unit; and a control unit coupled to the modem and the receiver unit, the control unit configured to:
determine an angle-of-arrival of a message received at the plurality of antennas from a wireless device;
compare the angle-of-arrival with angle-of-arrival threshold to determine whether to transmit a response message to the wireless device.

13 . The apparatus of claim 12 , wherein the control unit is configured to cause the response message to be transmitted to the wireless device if the angle-of-arrival is within the angle-of-arrival threshold, and to cause the response message not to be transmitted if the angle-of-arrival is not within the angle-of-arrival threshold.

14 . The apparatus of claim 12 , wherein the message is a probe request message sent by the wireless device that is a wireless client device operating in a wireless network and the control unit is configured to generate a probe response message to be transmitted to the wireless client device if the angle-of-arrival of the probe request message is within angle-of-arrival threshold.

15 . The apparatus of claim 14 , wherein the control unit is configured to adjust the angle-of-arrival threshold.

16 . The apparatus of claim 15 , wherein the control unit is configured adjust the angle-of-arrival threshold based on a command received from a wireless network controller.

17 . A method comprising:
for a plurality of wireless access point devices operating in a wireless network, determining coverage overlap between wireless access point devices; and based on the determined coverage overlap, adjusting an angle-of-arrival threshold used by respective one or more of the plurality of wireless access point devices when determining whether to respond to a probe request message received from a wireless client device.

18 . The method of claim 17 , wherein adjusting is based on coverage overlap determined between wireless access point devices.

19 . The method of claim 17 , wherein adjusting comprises adjusting the angle-of-arrival threshold to be used by a group of two or more of the plurality of wireless access point devices.

20 . The method of claim 18 , wherein adjusting comprises dynamically adjusting the angle-of-arrival threshold to be used by the group of two or more of the plurality of wireless access point devices based on conditions in the wireless network.

21 . The method of claim 17 , wherein adjusting is based on traffic load of the wireless access point devices.

Assignees

• Cisco Tech Inc

Inventors

• Diener Neil R
• Swartz John Matthew
• Stager Paul J
• Pang Tak Ming

Classifications

• H04W64/00 Primary

  Locating users or terminals {or network equipment} for network management purposes, e.g. mobility management · CPC title

• H04W48/16

  Discovering, processing access restriction or access information · CPC title

• H04W48/14 Primary

  using user query {or user detection} · CPC title

• H04W48/06

  based on traffic conditions · CPC title