Here I write about each and every channel of LTE with its Functionality. How many channel and what its work.
Physical channels
- PDSCH: Physical Downlink Shared Channel
- PBCH: Physical broadcast channel
- PMCH: Physical multicast channel
- PDCCH: Physical Downlink Control Channel
- PCFICH: Physical control format indicator channel
- PHICH: Physical Hybrid ARQ Indicator Channel
Reference Signal (RS)
- Cell specific RS
- UE-specific RS
- MBSFN RS
Synchronization Signal (SCH)
- Primary Synchronization Signal (P-SCH)
- Secondary Synchronization Signal (S-SCH)
SCH used for:
- Symbol synchronization
- Frame synchronization
- Cell-ID determination
- Basic L1/L2 system parameters
- Downlink system bandwidth
- Reference-signal transmit power
- Multi-media Broadcast over a Single Frequency Network (MBSFN)-related parameters
- Number of transmit antennas
- HARQ resource allocation
Control region is 1-3 OFDM symbols at the beginning of each subframe, composed of control channel elements (CCEs)
- 4 Res = Resource element group (REG)
- 9 REGs = 1 CCE
PCFICH – Physical Control Format Indicator Channel
- # of OFDM symbols of control region
PHICH – Physical Hybrid ARQ Channel
- ACK/NACK signaling
PDCCH – Physical Downlink Control Channel
- Scheduling
- UL power control