| 摘要 |
<p>A communication system comprises a central processing unit (1) and a plurality of N communication stations (2.1, 2.2, ..., 2.N), in which the central processing unit and the communication stations are coupled over an uplink signal line (3) and a downlink signal line (4). The downlink signal (Fig. 3) on the downlink signal line has the form of successive frames, each frame comprising M signal blocks (SBm), the first signal block in a frame comprising a synchronizing word (sync word) (22), the signal blocks all having space for storing audio information in the form of p audio words (21), the M-1 signal blocks not comprising a sync word further having space for storing control information, the control information in a signal block belonging to a communication station containing downlink assign information (a.dl + m) denoting which audio words in the signal blocks in a frame are destined for said communication station. The uplink signal (Fig. 4) has the form of successive frames having a time duration equal to the time duration of the frames in the downlink signal. Each frame has space for first signal blocks (30) each comprising two or more audio words, and second signal blocks (31) comprising control information. The control information in the downlink signal and destined for a station further includes uplink assign information (audio chan. upl + m) denoting what first signal blocks in a frame in the uplink signal originate from a station. Furthermore, there are gaps (36A) between the uplink signal blocks originating from different stations. <IMAGE></p> |
