04.033GPPMobile Station - Base Station System (MS - BSS) Interface Channel Structures and Access CapabilitiesRelease 1999TS
Packet data traffic channels are used to carry a wide variety of information streams, including user information and signalling information for, e.g. Session Management (SM) and Mobility Management (MM) in packet mode. A distinguishing characteristic is that a packet data traffic channel allows a plurality of information streams, associated with different users, to be multiplexed in a pre-emptive and dynamic fashion. Signalling functions between the MS and the BSS are carried out over other types of channels, namely the control channels.
Uni-directional information streams are carried on the packet data traffic channel on an alternate, or simultaneous basis, consistent with the packet data traffic channel carrying capability. The packet data traffic channel uses the radio resources referred to as PDTCH (see 3GPP TS 05.02).