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Glossary

PRACH (Physical Random Access Channel) in 3GPP: meaning and where it is specified

Published 2026-10-16Updated 2026-10-16

At a glance

Term
PRACH
Stands for
Physical Random Access Channel
Defined in
3GPP TR 21.905 V19.2.0, clause 4
Used in
TS 25.211, TS 25.221, TS 25.224

In plain words

PRACH means Physical Random Access Channel, the expansion listed in 3GPP TR 21.905, clause 4. TS 25.211 labels clause 5.2.2.1 Physical Random Access Channel, and TS 25.221 labels clause 5A.3.4 the physical random access channel. In TS 25.224, the RRC Layer selects a PRACH: "The selection of a PRACH is done by the RRC Layer."

Source: 3GPP TS 25.224 V16.0.0, clause 4.7.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/25_series/25.224/25224-g00.zip

Sources

  1. 3GPP TR 21.905 V19.2.0, clause 4. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/21_series/21.905/21905-j20.zip
  2. 3GPP TS 25.211 V19.0.0, clause 5.2.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/25_series/25.211/25211-j00.zip
  3. 3GPP TS 25.221 V18.0.0, clause 5A.3.4. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/25_series/25.221/25221-i00.zip
  4. 3GPP TS 25.224 V16.0.0, clause 4.7.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: https://www.3gpp.org/ftp/Specs/archive/25_series/25.224/25224-g00.zip

How this page was made

The facts box comes straight from the 3GPP TDoc list and specification archive as indexed by 3GPP Scout. An AI model (GPT-6 Luna) wrote the paragraph and named the source of each sentence. Code checked every quote word for word against the stored source text and every number against the cited source. A second AI model from another company (Claude Opus 5.5) reviewed the paragraph against the same sources. The 3GPP documents themselves govern.