| 摘要 |
<p>A method for the allocation of a control channel (PACCH) to mobile stations (MS) in a packet radio system, particularly in a GPRS system. The mobile station (MS) sends a resource allocation request (3-1), to which a network (BSS) responds (3-2) by allocating to the mobile station (MS) a TFI identifier and a USF identifier. The network then sends (3-5) data packets in blocks, at least some of which comprise a polling field (S/P), a polling state ('P') of which indicates that the mobile station is to acknowledge received data packets on the control channel (PACCH). To ensure that a mobile station receiving in downlink would not prevent the network from allocating one uplink mobile station to said channel, the allocation of the control channel (PACCH) is, in accordance with the invention, independent of a possible USF identifier. The mobile station acknowledges (3-6) the received data packets after a predetermined time (T) from the downlink block in which said polling field is in the polling state ('P'). The predetermined time (T) can be fixed or it can be indicated in an additional extension field (EF2). <IMAGE> <IMAGE></p> |
