The physical layer is expected to perform the following functions to provide the data transport service
- Error detection on the transport channel and indication to higher layers;
- FEC encoding/decoding of the transport channel;
- Hybrid ARQ soft-combining;
- Rate matching of the coded transport channel to physical channels;
- Mapping of the coded transport channel onto physical channels;
- Power weighting of physical channels;
- Modulation and demodulation of physical channels;
- Frequency and time synchronization;
- Radio characteristics measurements and indication to higher layers;
- Multiple Input Multiple Output (MIMO) antenna processing;
- RF processing
The physical layer offers data transport services to higher layers. Access to these services is through the use of transport channels via the MAC sub-layer. A transport block is defined as the data delivered by MAC layer to the physical layer and vice versa.
reference 38.201 , 4.2
