Logical channel — What kind of information this is

5G Systems Notes · Concept map · Logical channel Route · Hierarchy · Index · All concepts · Hub

The protocol stack

Where it sits

Sits at	Level 0 of the hierarchy · The protocol stack · explained
The 5 of them	`BCCH` — broadcast control — system information, for everyone in the cell `PCCH` — paging control — “wake up, there is something for you” `CCCH` — common control — for a device with no RRC connection yet `DCCH` — dedicated control — RRC reconfiguration, measurement orders `DTCH` — dedicated traffic — the user's own data, and the reason for all the rest
Learn first	Nothing — this is a place to start.
Unlocks	MAC · Transport channel
Primary clause	TS 38.300 §6.2.2
Used in	nr-pdsch 10 · ref-ue-mobility 2 · index 1 · ref-system 1

Scanned from the notes at page load and joined with terms.json; nothing on this card is typed by hand.

What it is

A logical channel is defined by what kind of information it carries — not by how it is carried. It is the topmost of the three channel abstractions.

Control channels: BCCH (broadcast system information), PCCH (paging), CCCH (control for a device with no connection yet), DCCH (dedicated control). Traffic channels: DTCH, the user's actual data. (TS 38.300 clause 6.2.2.)

MAC maps them onto transport channels; the physical layer maps those onto physical channels. Two renamings, and confusing them is the usual source of muddle.

Read on

The full treatment is in nr-pdsch — this page is the definition and the map reference; that note is where the subject is actually developed.

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Before this concept, the hierarchy says to learn the following — the full chain, in order:

Logical channel needs nothing first — it is one of the places to start reading.

Keep going — where this sits on the route

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