Link restoration in a fixed wireless transmission network

• US 20030161261A1
• Filed: 02/06/2003
• Published: 08/28/2003
• Est. Priority Date: 02/26/2002
• Status: Abandoned Application

• Current Assignee: Alcatel SA (Nokia Corporation)
• Original Assignee: Alcatel SA (Nokia Corporation)
• Inventors: Weis, Bernd X.
• Application Number:
  US10/359,242
• Publication Number:
  US 20030161261A1
• Time in Patent Office: Days
• US Class Current: 370/221
• CPC Class Codes: H04B 17/401 with selective localization
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0619 using feedback from receiving side feedback signaling for adaptive modulation/coding H04L1/0001

Abstract

Restoration of a link in fixed wireless transmission network, in the case of failure, is achieved by redirecting a directional antenna of a first network element from a second failed network element to a third network element, whereby a new microwave link in the network is established. A network element suited to allow fast and effective restoration in a fixed wireless transmission network has a directional antenna and corresponding control circuitry which are controlled by a control device to redirect transmission direction in the case of a failure. Preferably, the directional antenna is a phased array antenna. The control device can either be a central network management system or a local control system of the network node.

Claims

1. A method of restoring in the event of a failure a fixed wireless transmission network comprising a number of nodes each having at least one directional antenna pointing to another of said nodes for establishing a microwave link in the network, the method comprising the steps of:

detecting a microwave link failure of a receiving node in the network and

redirecting the transmission direction of the directional antenna of a transmitting node to a third node remote from said failed receiving node to restore the failed link over said third node.

2. A method according to claim 1, wherein said antenna is a phased array antenna and said step of redirecting the antenna comprises shifting the phases of feeding currents of said phased array antenna.

3. A method according to claim 1, comprising the steps of determining the position of the third node using GPS information, re-directing the antenna to this position and fine-tuning the direction to achieve substantially maximum reception power at the third node.

4. A method according to claim 1, further comprising the step of simultaneously re-transmitting received time-slots or packets with said directional antenna to multiple nodes using adaptive SMDA.

5. A network node of a fixed wireless transmission network comprising a directional antenna and corresponding control circuitry which are controlled by a control device to redirect transmission direction upon detection of a microwave link failure.

6. A network node according to claim 5, wherein said directional antenna is a phased array antenna.

7. A network node according to claim 6, wherein said control circuitry comprises phase shifters for shifting the phases of feeding currents of said phased array antenna.