Method of detection of signals using an adaptive antenna in a peer-to-peer network

• US 20040196822A1
• Filed: 02/09/2004
• Published: 10/07/2004
• Est. Priority Date: 09/13/2001
• Status: Active Grant

• Current Assignee: James A. Proctor Jr
• Original Assignee: James A. Proctor Jr
• Inventors: Proctor, James A. Jr.
• Granted Patent: US 7,586,880 B2
• Time in Patent Office: Days
• US Class Current: 370/349
• CPC Class Codes: H01Q 25/002 providing at least two patterns of different beamwidth; Variable beamwidth antennas
• CPC Class Codes: H01Q 3/2605 Array of radiating elements provided with a feedback control over the element weights, e.g. adaptive arrays
• CPC Class Codes: H04B 7/0608 Antenna selection according to transmission parameters
• CPC Class Codes: H04W 16/28 using beam steering

Abstract

An adaptive antenna signal identification process to provide increased interference rejection in a wireless data network, such as a wireless Local Area Network (LAN). An adaptive antenna, such as a directional antenna, can be steered to various angle of arrival orientations. For example, the adaptive antenna can be steered to the last known best direction for reception of a particular detected signal. When the invention is deployed in a relay function, messages received from a first node are forwarded to a second node using a recorded direction of best reception from the second node. Storage of the best antenna angle for propagation to neighbor nodes can be handled by control functions in a manner that is analogous to other router lookup tables, such as being contained in a lookup table that stores Internet Protocol (IP) addresses.

Claims

1. A method for operating a wireless data communication system in which a relay station having a directional antenna forwards messages from a first node to a second node using a wireless physical layer signaling protocol, the method comprising the steps of:

receiving from the first node a wireless transmission for delivery at the second node;

determining an identification of the second node from an initial portion of the wireless transmission;

determining, using the second node'"'"'s identification, a preferred antenna angle for the directional antenna;

steering the directional antenna according to the preferred antenna angle; and

retransmitting the wireless transmission to the second node using the directional antenna.

2. The method of claim 1, wherein the wireless data communication system is a wireless Local Area Network (LAN).

3. The method of claim 1, wherein the wireless transmission is received at the first node using a substantially omni-directional antenna.

4. The method of claim 1, wherein the wireless transmission is received at the first node using the directional antenna.

5. The method of claim 4, wherein the directional antenna is operated in an omni-directional antenna mode.

6. The method of claim 1, wherein determining the identification of the second node comprises utilizing messages at a protocol layer higher than a physical layer.

7. The method of claim 6, wherein determining the identification of the second node comprises utilizing a preamble portion of a Media Access Control (MAC) protocol layer.

8. The method of claim 6, wherein determining the identification of the second node comprises utilizing a link layer establishment message of a link protocol layer.

9. The method of claim 8, wherein the link-layer establishment message is a Request To Send (RTS) message.

10. The method of claim 1, wherein determining the preferred antenna angle comprises:

locating the second node'"'"'s identification in a lookup table storing a predetermined association between a node'"'"'s identification and its preferred antenna angle; and

determining the preferred antenna angle from the stored association for the second node'"'"'s identification.

11. The method of claim 10, wherein the second node'"'"'s identification is an Internet Protocol (IP) address.

12. The method of claim 10, wherein the preferred antenna angle corresponds to the best angle for propagation to the second node.

13. The method of claim 10, wherein the predetermined association between the second node'"'"'s identification and its preferred antenna angle is determined by:

stepping the antenna through a plurality of directional angles;

receiving a wireless transmission from the second node at each of the plurality of directional angles;

determining a received signal metric relating to the received signal;

identifying the directional angle having the best received signal metric;

associating the identified angle with the second node; and

recording in the lookup table the association of the identified angle with the second node'"'"'s identification.

14. The method of claim 13, wherein the steps of determining the preferred antenna angle are repeated for a plurality of nodes and the associations of each identified angle with its respective node'"'"'s identification is stored in a lookup table.

15. The method of claim 13, wherein the received signal metric is selected from the group consisting of:

Received Signal Strength Indication (RSSI);

Bit Error Rate (BER);

noise power level; and

combinations thereof.

16. An apparatus for operating a wireless data communication system in which a relay station having a directional antenna forwards messages from a first node to a second node using a wireless physical layer signaling protocol comprising:

means for receiving from the first node a wireless transmission for delivery at the second node;

means for determining an identification of the second node from an initial portion of the wireless transmission;

means for determining, using the second node'"'"'s identification, a preferred antenna angle for the directional antenna;

means for steering the directional antenna according to the preferred antenna angle; and

means for retransmitting the wireless transmission to the second node using the directional antenna.