Sectorized wireless communication network operating under 802.11 specifications

• US 7,596,388 B2
• Filed: 02/28/2005
• Issued: 09/29/2009
• Est. Priority Date: 02/28/2005
• Status: Active Grant

• Current Assignee: Extreme Networks, Inc.
• Original Assignee: Symbol Technologies, Inc. (Zebra Technologies Corporation)
• Inventors: Sharony, Jacob, Willins, Bruce A.
• Primary Examiner(s): Donovan; Lincoln
• Assistant Examiner(s): Luo; David S
• Application Number:
  US11/068,510
• Publication Number:
  US 20060194616A1
• Time in Patent Office: 1,674 Days
• Field of Search: 455/73, 455/550.1, 455/561, 455/562.1, 455/403, 455/422.1, 455/63.4
• US Class Current: 455/562.1
• CPC Class Codes: H04W 16/24 Cell structures
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Methods and systems are provided to facilitate communication with a plurality of remote units in a communication area that includes a plurality of spatial sectors. The system includes a network controller configured to receive and transmit under IEEE 802.11 specifications, and a plurality of directional antennas coupled to the network base station. Each of directional antennas functions as an access point for a respective spatial sector. The directional antennas and the network controller are combined as a single base station apparatus in an exemplary embodiment. Further, an exemplary network controller is configured to concurrently transmit a plurality of the data frames to more than one of the spatial sectors, and to synchronize the transmissions in a manner whereby all of the concurrently transmitted frames end simultaneously.

Claims

1. A wireless network device comprising:

a plurality of directional antennas, each directional antenna adapted to transmit and receive data frames and configured to operate in a different direction, forming spatial sectors; and

a network controller coupled to each of the plurality of directional antennas and adapted to transmit at least two data frames substantially simultaneously using at least two of the directional antennas, the network controller adapted to synchronize transmissions of the at least two data frames such that the ends of the transmissions occur substantially simultaneously, the network controller further adapted to detect wireless transmissions using each of the directional antennas and to delay transmission of at least one data frame through at least one of the directional antennas in response to detection of a wireless transmission.

2. The wireless network device of claim 1, wherein the network controller is adapted to transmit the at least one data frame such that the end of the at least one data frame is synchronized with the end of a non-delayed data frame.

3. The wireless network device of claim 2, wherein the delayed data frame and non-delayed data frame are different lengths.

4. A wireless network device comprising:

a plurality of directional antennas, each directional antenna adapted to transmit and receive data frames and configured to operate in a different direction, forming spatial sectors; and

a network controller coupled to each of the plurality of directional antennas and adapted to transmit at least two data frames substantially simultaneously using at least two of the directional antennas, the network controller adapted to synchronize transmissions of the at least two data frames such that the ends of the transmissions occur substantially simultaneously, the network controller further adapted to detect wireless transmissions using each of the directional antennas and to assert carrier sense in at least one spatial sector with at least one of the plurality of directional antennas in response to detecting a signal with a different directional antenna.

5. A wireless network device comprising:

a plurality of directional antennas, each directional antenna adapted to transmit and receive data frames and configured to operate in a different direction, forming spatial sectors; and

a network controller coupled to each of the plurality of directional antennas and adapted to transmit at least two data frames substantially simultaneously using at least two of the directional antennas, the network controller adapted to synchronize transmissions of the at least two data frames such that the ends of the transmissions occur substantially simultaneously, wherein each of the at least two data frames has a different length.

6. A method of communicating with wireless devices comprising:

transmitting a first data frame in a first spatial sector using a first directional antenna; and

transmitting a second data frame in a second spatial sector using a second directional antenna, the transmission of the first and second data frames being synchronized to end substantially simultaneously, wherein the first and second directional antennas are controlled by a network controller.

7. A method of communicating with wireless devices comprising:

transmitting a first data frame in a first spatial sector using a first directional antenna; and

transmitting a second data frame in a second spatial sector using a second directional antenna, the transmission of the first and second data frames being synchronized to end substantially simultaneously, wherein transmitting the first data frame comprises beginning transmission at a first time, and transmitting the second data frame comprises beginning transmission at a second time, the first and second times not being substantially the same time.

8. A method of communicating with wireless devices comprising:

transmitting a first data frame in a first spatial sector using a first directional antenna;

transmitting a second data frame in a second spatial sector using a second directional antenna, the transmission of the first and second data frames being synchronized to end substantially simultaneously; and

receiving a first wireless transmission with at least one of the first and second directional antennas before transmitting the first or second data frames.

9. The method of claim 8, further comprising queueing the first and second data frames for transmission until the end of receiving the first wireless transmission.

10. A method of inhibiting interference in a wireless network comprising:

detecting a first wireless signal in a first spatial sector using a first directional antenna coupled to a network controller, the first wireless signal being received in a first period and wherein detecting a first wireless signal comprises receiving a data frame with the first directional antenna; and

asserting carrier sense in a second spatial sector using a second directional antenna coupled to the network controller in response to detecting the first wireless signal.

11. A method of inhibiting interference in a wireless network comprising:

detecting a first wireless signal in a first spatial sector using a first directional antenna coupled to a network controller, the first wireless signal being received in a first period; and

asserting carrier sense in a second spatial sector using a second directional antenna coupled to the network controller in response to detecting the first wireless signal, wherein asserting carrier sense in a second spatial sector has a duration at least as long as the first period.

12. A method of inhibiting interference in a wireless network comprising:

detecting a first wireless signal in a first spatial sector using a first directional antenna coupled to a network controller, the first wireless signal being received in a first period;

asserting carrier sense in a second spatial sector using a second directional antenna coupled to the network controller in response to detecting the first wireless signal; and

delaying transmission of a data frame in response to detecting the first wireless signal.