Patent ID: 7136361
Filing Date: 2006-11-14
Classification: H04L,H04W

Abstract:
1. A method for enabling a plurality of overlapped wireless LAN cells to have contention-free access to a medium, each cell including a respective plurality of member stations, comprising: assigning a first inter-cell contention-free period value to a first access point station in a first cell, associated with an accessing order in the medium for member stations in first and second cells of the plurality of cells during a transmission frame; transmitting by the first access point station in the first cell, a beacon packet containing the first inter-cell contention-free period value; receiving the beacon packet at an overlapped station occupying the first cell and the second cell, and forwarding the inter-cell contention-free period value to member stations in the second cell, to delay transmissions by member stations in the second cell until after said first inter-cell contention-free period; assigning a second inter-cell contention-free period value to a second access point station in the second cell, associated with said accessing order; transmitting by the second access point station in the second cell, a second beacon packet containing the second inter-cell contention-free period value; receiving the second beacon packet at an overlapped station occupying said first cell and said second cell, and forwarding the second inter-cell contention-free period value to member stations in the first cell to delay transmissions by member stations in the first cell until after said second inter-cell contention-free period; receiving the first inter-cell contention-free period value and the second inter-cell contention-free period value at a third access point station in a third cell overlapped with said first cell and said second cell; selecting a backoff time for said third access point station following the second inter-cell contention-free period, to begin transmission by the third access point station in the third cell of a third beacon packet containing a third inter-cell contention-free period value; and receiving the third beacon packet at an overlapped station occupying said first cell and an overlapped station occupying said second cell, and forwarding the third inter-cell contention-free period value to member stations in the first and second cells to delay transmissions by member stations in the first and second cells until after said third inter-cell contention-free period.