Transmission system between base station and switching center of mobile communications using fixed length cell

A communication apparatus for transmitting information using fixed length cells, comprising:

• means for generating, when there are a plurality of calls to be handled and there are at least two different information transfer rates in information transfer rates required of the plurality of calls, fixed length cells bearing information of each of the plurality of calls, at a period of a value which is inversely proportional to the information transfer rate required of the call;
• means for preparing frames, each of the frames having cell slots the number of which is equal to the number of the plurality of calls, and a transfer period of the frames being equal to the minimum value of the values which are inversely proportional to the information transfer rates required of the plurality of calls;
• means for mounting the generated fixed length cells on the cell slots of the prepared frames;
• and
• means for carrying out periodic transfer of the frames in which the fixed length cells have been mounted on the cell slots.