Resource block — Twelve consecutive subcarriers

5G Systems Notes · Concept map · Resource block Route · Live ↗ · Hierarchy · Index · All concepts · Hub

The grid and its units

This page is the explanation. resource block, live is the working half — the same quantities computed by 5G Simulation/ while the page loads, so they cannot drift from what is written here.

Where it sits

Sits atLevel 4 of the hierarchy · The grid and its units · explained
The 3 of them
CRB — common resource block — numbered from Point A, the absolute grid
PRB — physical resource block — numbered inside a bandwidth part
VRB — virtual resource block — what the DCI allocates, before interleaving
Learn firstResource element — 4 concepts in the full chain, see the paths
UnlocksPoint A · REG and CCE · SS/PBCH block · Bandwidth part · PDSCH
Primary clauseTS 38.211 §4.4.4.4
Used innr-pdsch 16 · nr-frame-structure 13 · nr-srs 2 · ref-signals 1 · index 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 resource block is twelve consecutive subcarriers. It is the unit the scheduler actually allocates in frequency — nothing smaller is ever assigned.

Twelve at every numerology, so a block's width in hertz scales with the subcarrier spacing: 180 kHz at 15 kHz spacing, 360 kHz at 30 kHz, and so on.

Three flavours, and confusing them is the usual mistake (clauses 4.4.4.3 to 4.4.4.5): common resource blocks are numbered from point A across the whole carrier; physical ones are numbered within a bandwidth part; virtual ones are what an allocation names before the interleaver maps them to physical ones.

Read on

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

Widget not found: sim_status

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

To understand Resource block (level 4) you first need 4 other concepts. Read them in this order — everything on one line can be read in any order, but no line before the one above it:
Immediately before Resource block: Resource element.
Keep going — where this sits on the route
The route is every concept in the folder ordered by level, so nothing here needs anything after it. Computed at page load from terms.json; the same numbering as the route page.
5G Systems Notes · Concept map · Resource block Top · Concept map · Hub