6 Mapping and association of physical channels

25.2113GPPPhysical channels and mapping of transport channels onto physical channels (FDD)Release 17TS

6.1 Mapping of transport channels onto physical channels

Figure 27 summarises the mapping of transport channels onto physical channels.

Figure 27: Transport-channel to physical-channel mapping

The DCHs are coded and multiplexed as described in [3], and the resulting data stream is mapped sequentially (first-in-first-mapped) directly to the physical channel(s). The mapping of BCH and FACH/PCH is equally straightforward, where the data stream after coding and interleaving is mapped sequentially to the CCPCHs. A BCH can be mapped to either Primary CCPCH or Secondary CCPCH, while FACH/PCH is always mapped to Secondary CCPCH. Also for the RACH, the coded and interleaved bits are sequentially mapped to the physical channel, in this case the message part of the PRACH. The E-DCH is coded as described in [3], and the resulting data stream is mapped sequentially (first-in-first-mapped) directly to the physical channel(s).

6.2 Association of physical channels and physical signals

Figure 28 illustrates the association between physical channels and physical signals.

Figure 28: Physical channel and physical signal association