Space-time-power scheduling for wireless networks

• US 9,014,203 B2
• Filed: 12/15/2010
• Issued: 04/21/2015
• Est. Priority Date: 08/26/2002
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Scherzer, Shimon B., Worfolk, Patrick A.
• Primary Examiner(s): Pezzlo, John
• Application Number:
  US12/969,286
• Publication Number:
  US 20110085532A1
• Time in Patent Office: 1,588 Days
• Field of Search: 370/252, 370/329, 370/461, 370/338, 370/419
• US Class Current: 370/419
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 52/24 using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 88/12 Access point controller devices

Abstract

A technique is disclosed to schedule frame transmissions in a wireless local area network. The network includes a plurality of stations configured to communicate on the same frequency channel with a plurality of access points. A central controller examines the transmission characteristics between the various stations and access points and identifies frames that may be simultaneously transmitted by a subset of the access points to their intended stations.

Claims

1. An access point to wirelessly communicate with a station, said access point comprising:

an array of antennas, wherein each of the antennas comprises a port;

a beam forming network to form multiple beams from the array of antennas;

a switch connected to the beam forming network;

a test receiver to scan the ports of the array of antennas through the switch to determine at least one of (1) responses from the station and (2) signal-to-noise ratios (SNRs) of the station;

an analog transceiver coupled to the switch;

wherein the access point is to communicate the at least one of (1) responses from the station and (2) SNRs of the station to a central controller for use by the central controller to schedule downlink frame transmissions for the access point, and

wherein the access point is to communicate with the central controller using the analog transceiver.

2. The access point according to claim 1, wherein the multiple beams formed from the array of antennas are orthogonal to each other.

3. The access point according to claim 1, wherein the array of antennas are designed for one of omni-directional and sector coverage.

4. The access point according to claim 1, wherein the access point is to receive frame transmissions from the central controller and to communicate the frame transmissions to the station.

5. The access point according to claim 1, further comprising:

an 802.11 chipset to modulate and demodulate the at least one of (1) responses from the station and (2) SNRs of the station.

6. The access point according to claim 1, further comprising:

an analog-to-digital converter;

a correlator; and

a controller to receive samples converted by the analog-to-digital converter and to perform fast correlation functions using the correlator.

7. The access point according to claim 1, wherein the access point does not include a 802.11 chipset.

8. The access point of claim 1, further comprising:

a plurality of line transceivers coupled to the analog transceiver,

wherein the access point is to communicate with the central controller through the plurality of line transceivers.

9. A method of implementing an access point to wirelessly communicate with a station, said method comprising:

determining, in the access point, at least one of;

(1) responses from the station and (2) signal-to-noise ratios (SNRs) of the station;

communicating, to a central controller via an analog transceiver of the access point, the at least one of;

(1) responses from the station and (2) SNRs of the station for the central controller to schedule downlink frame transmissions for the access point;

receiving the scheduled downlink frame transmissions from the central controller; and

communicating the frame transmissions to the station.

10. The method according to claim 9, wherein the access point comprises an array of antennas and a beam forming network to form multiple beams from the array of antennas, and wherein the access point is to receive uplink frames from the station through the multiple beams, said method further comprising:

selecting one of the multiple beams to communicate with the station based upon characteristics of the uplink frames received through the array of antennas.

11. The method according to claim 9, wherein determining, in the access point, at least one of responses from the station and SNRs of the station further comprises determining at least one of channel gains between the access point and the station, probability of station to station interference, access point transceiver to station path loss, and station to station path loss information.

12. The method according to claim 9, further comprising:

polling, by the access point, the station when an uplink frame transmission from the station has not occurred for a specified period of time.

13. The method of claim 9, wherein a plurality of line transceivers are coupled to the analog transceiver of the access point, and

wherein the access point communicates with the central controller through the plurality of line transceivers.