There are major four channel in LTE Downlink trasport channel. which list below with its work in short.
Paging Channel ( PCH)
- Supports UE discontinuous reception (DRX) to enable UE power saving.
- Broadcasts in the entire coverage area of the cell.
- Mapped to physical resources which can be used dynamically also for traffic/other control channels.
Broadcast Channel ( BCH )
- The LTE transport channel maps to Broadcast Control Channel (BCCH).
- Fixed, pre-defined transport format.
- Broadcast in the entire coverage area of the cell.
Multicast Channel ( MCH)
- Broadcasts in the entire coverage area of the cell.
- Supports MBSFN combining of MBMS transmission on multiple cells.
- Supports semi-static resource allocation e.g.with a time frame of along cyclic prefix.
Downlink Shared Channel ( DL-SCH )
- Main channel for downlink data transfer. It is used by many logical channels.
- Supports Hybrid ARQ.
- Supports dynamic link adaptation by varying the modulation, coding and transmit power.
- Optionally supports broadcast in the entire cell.
- Optionally supports beam forming.
- Supports both dynamic and semi-static resource allocation.
- Supports UE discontinuous reception (DRX) to enable UE power saving.
- Supports MBMS transmission.