	US 7,349,366 B2
	Overlap mitigation in wireless LANs using a central medium access control
Arie Johannes de Heer, Twente (Netherlands); and Harold Wilhelm Teunissen, Overijssel (Netherlands)
Assigned to Lucent Technologies Inc., Murray Hill, N.J. (US)
Filed on Apr. 10, 2003, as Appl. No. 10/411,173.
Claims priority of application No. 02252555 (EP), filed on Apr. 10, 2002.
Prior Publication US 2003/0202498 A1, Oct. 30, 2003
Int. Cl. H04Q 7/00 (2006.01); H04B 7/00 (2006.01); H04J 3/06 (2006.01)

U.S. Cl. 370—328 [370/337; 370/350; 455/41.2; 455/456.4; 455/502]

6 Claims

1. An access point for a wireless local area network, the access point being arranged to service at least one station by using a central medium access control protocol during a time period, and to monitor overlap with neighbouring access points, and to define one or more areas in which at least one first station experiences overlap, as being overlap areas, and one or more areas in which at least one second station does not experience overlap, as being non-overlap areas, and to define one or more neighbouring access points causing the overlap as being overlapping neighbouring access points, the accesspoint comprising:

a processor device operable such that the access point and the overlapping rieigbouring access points synchronize in such a way that the access point can service the at least one first station in the overlap areas during a servicing time within the time period, while the overlapping neighbouring access points are silent, and vice versa, and

said device further being operable such that the access point is further arranged to determine the amount of the servicing time by exchanging requests for silence with its overlapping neighbouring access points, wherein said access point is arranged to execute a silence trade-off mechanism which includes:

(a) initialisation of an own supply for silence;

(b) determination of a total period of time available for resolving overlap;

(d) exchanging of an amount of time which is available by the access point for resolving overlap with its neighbouring access points;

(e) combination of coincident demands using a predetermined combination rule;

(f) determination of an effective overlapping time according to a predetermined overlap time rule;

(g) setting the own supply for silence to the effective overlapping time;

(h) determination of a minimum of demands and supplies for silence according to a minimum determination rule;

(i) calculation of the own supply of silence;

(j) repeat the previous steps until a predefined criteria is met.