Patent ID: 6693915
Filing Date: 2004-02-17
Classification: H04W

Abstract:
A method in a wireless data transmission system (1) which comprises wireless terminals (MT1-MT4), at least a first access point (AP1) and a first access point controller (AC1), and a second access point (AP2) and a second access point controller (AC2), in which methodfirst data frames (FR1) and second data frames (FR2) are established, the controller (AC1) of the first access point controls the transmission and reception of the first data frames (FR1) between the first access point (AP1) and the wireless terminals (MT1, MT2) communicating with the first access point, wherein said first data frames (FR1) are used in the data transmission between the first access point (AP1) and the wireless terminals (MT1, MT2) communicating with the first access point, the controller (AC2) of the second access point controls the transmission and reception of the second data frames (FR2) between the second access point (AP2) and the wireless terminals (MT3, MT4) communicating with the second access point, wherein said second data frames (FR2) are used in the data transmission between the second access point (AP2) and the wireless terminals (MT3, MT4) communicating with the second access point, the first (FR1) and the second data frames (FR2) comprise at least one control field (C1, C2) and data field (D1, D2), from said data field (D1, D2) time slots (TS11-TS1n, TS21-TS2n) are allocated for the communication of data transmission connections, and in which wireless data transmission system (1) one or more channel frequencies are used in the transmission and reception of the data frames (FR1, FR2), wherein each data transmission connection is allocated one of said channel frequencies, characterized in that also in the methoda first starting point (TS11, TS21) and a second starting point (TS1n, TS2n) are determined from said data field (D1, D2), a first allocation strategy is determined, in which the allocation of the time slots (TS11-TS1n, TS21-TS2n) of the data field (D1, D2) is started from said first starting point (TS11, TS21) of the data field, and a second allocation strategy is determined, in which the allocation of the time slots (TS11-TS1n, TS21-TS2n) of the data field (D1, D2) is started from said second starting point (TS11, TS21) of the data field, and information on the allocation strategy used in the data frame (FR1, FR2) is attached to the data frame (FR1, FR2), and the transmission and reception of the first data frames (FR1) is synchronized with the transmission and reception of the second data frames (FR2), wherein at the first access point (AP1), the allocation strategy of the second data frames (FR2) is examined, and that allocation strategy which is not used in the second data frames (FR2) is selected for the first data frames (FR1).