BI-DIRECTIONAL LINK MARGIN ESTABLISHMENT FOR WIRELESS EMBEDDED SYSTEMS

• US 20130194959A1
• Filed: 10/05/2010
• Published: 08/01/2013
• Est. Priority Date: 10/05/2010
• Status: Active Grant

• Current Assignee: UTC Fire & Security Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: UTC Fire & Security Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Huet de Bacellar, Luiz Fernando, Tiwari, Ankit
• Granted Patent: US 9,648,505 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements

Abstract

A method for bi-directional link margin establishment includes sending a first link margin exchange packet by a wireless end point (WEP) to a wireless access point (WAP); measuring an uplink signal strength of the first packet; sending to the WEP a second packet comprising the measured uplink signal strength of the first packet; measuring a downlink signal strength of the second packet; calculating an uplink link margin based on the uplink signal strength from the second packet; sending to the WAP a third packet comprising the measured downlink signal strength of the second packet and the calculated uplink link margin; measuring the uplink signal strength of the third packet; calculating a downlink link margin based on the downlink signal strength from the third packet; and sending to the WEP a fourth packet comprising the measured uplink signal strength of the third packet and the calculated downlink link margin.

Claims

1. A method for bi-directional link margin establishment in a wireless embedded system, the wireless embedded system comprising a wireless end point (WEP) and a wireless access point (WAP), the method comprising:

sending a first link margin exchange packet by the WEP to the WAP;

measuring by the WAP an uplink signal strength of the first link margin exchange packet;

sending by the WAP to the WEP a second link margin exchange packet comprising the measured uplink signal strength of the first link margin exchange packet;

measuring by the WEP a downlink signal strength of the second link margin exchange packet;

calculating by the WEP an uplink link margin based on the uplink signal strength from the second link margin exchange packet;

sending by the WEP to the WAP a third link margin exchange packet comprising the measured downlink signal strength of the second link margin exchange packet and the calculated uplink link margin;

measuring by the WAP the uplink signal strength of the third link margin exchange packet;

calculating by the WAP a downlink link margin based on the downlink signal strength from the third link margin exchange packet; and

sending by the WAP to the WEP a fourth link margin exchange packet comprising the measured uplink signal strength of the third link margin exchange packet and the calculated downlink link margin.

2. The method of claim 1, further comprising repeating measuring the signal strength of a received packet, recalculating the link margin based on the signal strength received in the packet, and sending a link margin exchange packet comprising the measured signal strength and the calculated link margin by the WEP to the WAP and by the WAP to the WEP a predetermined number of times.

3. The method of claim 2, wherein the predetermined number of times is at least 20.

4. The method of claim 1, further comprising determining by the WEP whether to join the WAP based on the calculated uplink link margin and the calculated downlink link margin.

5. The method of claim 1, further comprising providing a visual indication of whether the calculated uplink link margin is above a predetermined uplink link margin threshold, and the calculated downlink link margin is above a predetermined downlink link margin threshold.

6. The method of claim 1, further comprising assigning matching association codes to the WAP and the WEP before the WEP sends the first link margin exchange packet.

7. The method of claim 1, wherein the WEP and the WAP comprise respective computer program products comprising respective computer readable storage mediums containing respective computer code that, when executed by a computer, implement the method for bi-directional link margin establishment in a wireless embedded system.

9. The WEP of claim 7, wherein the WEP is further configured to repeat receiving from the WAP a packet;

measuring the downlink signal strength of the received packet, recalculating the uplink link margin based on an uplink signal strength received in the packet, and sending to the WAP a link margin exchange packet comprising the measured downlink signal strength and the calculated uplink link margin a predetermined number of times.

11. The WEP of claim 7, wherein the WEP is further configured to determine whether to join the WAP based on the calculated uplink link margin and the calculated downlink link margin.

12. The WEP of claim 7, wherein the WEP is further configured to provide a visual indication of whether the calculated uplink link margin is above a predetermined uplink link margin threshold, and the calculated downlink link margin is above a predetermined downlink link margin threshold.

13. The WEP of claim 7, wherein the WEP is further configured to receive an association codes corresponding to an association code of the WAP before the WEP sends the first link margin exchange packet.

8. A wireless end point (WEP) configured to:

send to a wireless access point (WAP) a first link margin exchange packet;

receive from the WAP a second link margin exchange packet comprising a measured uplink signal strength of the first link margin exchange packet;

measure a downlink signal strength of the second link margin exchange packet;

calculate an uplink link margin based on the uplink signal strength from the second link margin exchange packet; and

send to the WAP a third link margin exchange packet comprising the measured downlink signal strength of the second link margin exchange packet and the calculated uplink link margin.

10. The WEP of claim 8, wherein the predetermined number of times is at least 10.

14. The WEP of claim 8, wherein the WEP comprises a computer program product comprising a computer readable storage medium containing executable computer code.

15. A wireless access point (WAP) configured to:

receive from a wireless end point (WEP) a first link margin exchange packet;

measure an uplink signal strength of the first link margin exchange packet;

send to the WEP a second link margin exchange packet comprising the measured uplink signal strength of the first link margin exchange packet;

receive from the WEP a third link margin exchange packet comprising a measured downlink signal strength of the second link margin exchange packet and a calculated uplink link margin;

measure the uplink signal strength of the third link margin exchange packet;

calculate a downlink link margin based on the downlink signal strength from the third link margin exchange packet; and

send to the WEP a fourth link margin exchange packet comprising the measured uplink signal strength of the third link margin exchange packet and the calculated downlink link margin.

16. The WAP of claim 15, wherein the WAP is further configured to repeat receiving from the WEP a packet, measuring the uplink signal strength of the received packet, recalculating the downlink link margin based on a downlink signal strength received in the packet, and sending to the WEP a link margin exchange packet comprising the measured uplink signal strength and the calculated downlink link margin a predetermined number of times.

17. The WAP of claim 16, wherein the predetermined number of times is at least 10.

18. The WAP of claim 15, wherein the WAP is further configured to form a wireless network with the WEP based on the calculated uplink link margin and the calculated downlink link margin.

19. The WAP of claim 15, wherein the WAP is further configured to receive an association codes corresponding to an association code of the WEP before the WEP sends the first link margin exchange packet.

20. The WAP of claim 15, wherein the WAP comprises a computer program product comprising a computer readable storage medium containing executable computer code.