Adaptive power level setting in an ad-hoc wireless network

• US 6,970,714 B2
• Filed: 04/30/2002
• Issued: 11/29/2005
• Est. Priority Date: 04/30/2002
• Status: Expired due to Term

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: D'Souza, Raissa M., Lang, Duncan Temple, Ramanathan, Sharad
• Primary Examiner(s): Kincaid, Lester G.
• Assistant Examiner(s): DOAN, PHUOC HUU
• Application Number:
  US10/136,567
• Publication Number:
  US 20030203742A1
• Time in Patent Office: 1,309 Days
• Field of Search: 455/41.2, 455/41.3, 455/69, 455/522, 455/13.4, 455/14, 455/15, 342/465, 342/442
• US Class Current: 455/522
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 52/282 taking into account the speed of the mobile
• CPC Class Codes: H04W 52/283 Power depending on the position of the mobile
• CPC Class Codes: H04W 52/34 TPC management, i.e. sharing limited amount of power among users or channels or data types, e.g. cell loading
• CPC Class Codes: H04W 52/46 in multi hop networks, e.g. wireless relay networks
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

Wireless devices within an ad-hoc wireless network adaptively set their transmission power levels based on locally available information. Initially, each such wireless device sets its transmission power level to a relatively low level, and gradually increases its power level up to a predetermined maximum transmission power level. As the transmission power increases, the wireless device is able to incrementally connect with additional wireless devices located at increasing distances from the wireless device. As the wireless device connects with these additional wireless devices, it checks a connectivity constraint. When the connectivity constraint is satisfied, the wireless device stops increasing its power and operates at its current power level. In one embodiment, the connectivity constraint is a geometric connectivity constraint based on the angular distribution of wireless device connections. When a wireless device detects a change in the network topology, it repeats the power setting steps in order to adapt to the changed topology.

Claims

1. A method for adaptive power setting of a first wireless device in an ad-hoc wireless network comprising the steps of:

initially operating said first wireless device at a first transmission power level, said first transmission power level being selected at a level not expected to facilitate a connection between said first wireless device and additional wireless devices;

increasing the transmission power level, up to a predetermined maximum power level, while incrementally connecting with additional wireless devices; and

terminating said step of increasing the transmission power level, and operating said first wireless device at a current transmission power level, if connection with a particular one of said additional wireless device causes a connectivity constraint to be satisfied, wherein said connectivity constraint is a geometric connectivity constraint, said geometric connectivity constraint is based on an angular distribution between said connected additional wireless devices such that said connectivity constraint is satisfied when said angular distribution is less than or equal to one hundred eight degrees (180°

).

2. The method of claim 1 further comprising the step of:

reducing the transmission power level to operate at a transmission power level which caused connectivity to an additional wireless device if said predetermined maximum transmission power is reached prior to satisfying said connectivity constraint.

3. The method of claim 1 wherein the steps of claim 1 are repeated upon detection of a change in the topology of the ad-hoc wireless network.

4. A wireless device comprising:

a control processor for controlling the operation of the wireless device, said control processor adapted such that the wireless device performs the steps of;

initially operating at a first transmission power level, said first transmission power level being selected at a level not expected to facilitate a connection between said wireless device and additional wireless devices;

increasing the transmission power level, up to a predetermined maximum power level, while incrementally connecting with additional wireless devices; and

terminating said step of increasing the transmission power level, and operating at a current transmission power level, if connection with a particular one of said additional wireless device causes a connectivity constraint to be satisfied, wherein said connectivity constraint is a geometric connectivity constraint, said geometric connectivity constraint is based on an angular distribution between said connected additional wireless devices such that said connectivity constraint is satisfied when said angular distribution is less than or equal to one hundred eight degrees(180°

).

5. The wireless device of claim 4 wherein said control processor is adapted such that the wireless device performs the further step of:

reducing the transmission power level to operate at a transmission power level which caused connectivity to an additional wireless device if said predetermined maximum transmission power is reached prior to satisfying said connectivity constraint.

6. The wireless device of claim 4 wherein said control processor is adapted such that the wireless device repeats the steps set forth in claim 4 upon detection of a change in the topology of the ad-hoc wireless network.

7. A wireless device for operation in an ad-hoc wireless network comprising:

means for initially operating said first wireless device at a first transmission power level, said first transmission power level being selected at a level not expected to facilitate a connection between said wireless device and additional wireless devices;

means for increasing the transmission power level, up to a predetermined maximum power level, while incrementally connecting with additional wireless devices; and

means for terminating said step of increasing the transmission power level, and operating said first wireless device at a current transmission power level, if connection with a particular one of said additional wireless device causes a connectivity constraint to be satisfied, wherein said connectivity constraint is a geometric connectivity constraint, said geometric connectivity constraint is based on an angular distribution between said connected additional wireless devices such that said connectivity constraint is satisfied when said angular distribution is less than or equal to one hundred eight degrees(180°

).

8. The wireless device of claim 7 further comprising:

means for reducing the transmission power level to operate at a transmission power level which caused connectivity to an additional wireless device if said predetermined maximum transmission power is reached prior to satisfying said connectivity constraint.

9. The wireless device of claim 7 further comprising means for repeating the steps of claim 7 upon detection of a change in the topology of the ad-hoc wireless network.