The other channels — control, broadcast, and the uplink
PDSCH §1.1 counts three downlink physical channels and gives one of them a whole note. This note defines the other five, plus the machinery around PDCCH that the PDSCH note kept naming and never opened: the CORESET, the search space, and the RNTI.
In one line. PDSCH carries the data; everything here exists so that a device can find the data, join the cell in the first place, and answer back.
Concepts defined here. PDCCH · CORESET · Search space · RNTI · PBCH · Initial access · PRACH · PUCCH · PUSCH
The concepts this note covers
Each concept now has a page of its own. This note is the narrative — the group read as one argument, with the connective tissue that a page-per-concept cannot carry. The pages are the definitions, and each one shows what to learn before it.
| Concept | What it is | Needs | Primary clause |
|---|---|---|---|
| CORESET | The configured region PDCCH may occupy | 2 | TS 38.211 §7.3.2.2 |
| Initial access | From nothing to connected | 4 | TS 38.213 §4, §8 |
| PBCH | Physical broadcast channel — how to join a cell | 2 | TS 38.211 §7.3.3, §7.4.3 |
| PDCCH | Physical downlink control channel — the assignment | 3 | TS 38.211 §7.3.2 |
| PRACH | Physical random access channel — the first thing a device sends | 2 | TS 38.211 §6.3.3, TS 38.213 §8 |
| PUCCH | Physical uplink control channel — where HARQ-ACK and CSI go | 3 | TS 38.211 §6.3.2, TS 38.213 §9 |
| PUSCH | Physical uplink shared channel — the mirror of PDSCH | 2 | TS 38.211 §6.3.1, TS 38.214 §6 |
| REG and CCE | The units PDCCH is built from | 2 | TS 38.211 §7.3.2.1, §7.3.2.2 |
| RNTI | Radio network temporary identifier — the address that is not a field | 1 | TS 38.321 §7.1 |
| Search space | Where a device looks for a DCI, and how often | 2 | TS 38.213 §10.1 |
Which to read. Come here to see how these ideas hang together; go to a term page when you want one definition, its prerequisites, and everything that depends on it. The concept map indexes all 118, and its hierarchy puts them in learning order.
Sources
| Document | Clause | What it gives |
|---|---|---|
| TS 38.211 | 7.3.2 | PDCCH — CCE, REG, Table 7.3.2.1-1 aggregation levels, CORESET, CCE-to-REG mapping |
| 7.3.3, 7.4.3 | PBCH and the SS/PBCH block | |
| 6.3.2 | PUCCH formats 0 to 4 | |
| 6.3.1 | PUSCH, including DFT-s-OFDM | |
| 6.3.3, 5.3.2 | PRACH, and its own sequence generation | |
| TS 38.212 | 7.3.2 | DCI CRC and RNTI scrambling |
| 7.1 | PBCH payload generation, coding and the 864-bit rate matching | |
| TS 38.213 | 10.1 | Search spaces, candidates, and the blind-decode limits |
| 9.2 | Clause 9.2.2, the PUCCH format selection rule; Table 9.2.1-1, the common resource set | |
| 8, 13 | PRACH resources; CORESET 0 configuration from the MIB | |
| TS 38.214 | 5.1.3, 5.1.4, 6 | What each RNTI changes; PUSCH procedures |
| TS 38.321 | 5.1 | The random access procedure, Msg1 to Msg4 |