School of Specs Ambient IoT — a tag with no batteryQuick start

TS 23.369 · version 20.0.0 · 128 clauses · Quick start · 20 minutes

Ambient IoT — a tag with no battery

Ambient IoT is a way for a mobile network to talk to tags that have no battery. They run on scavenged energy and the cheapest of them never transmits at all: it reflects a plain tone somebody else is sending. Four short chapters: what the system is and what it is for, the parts it is made of, how a tag is actually read from the first page to the answer, and what its security protects and knowingly does not. Everything here was read out of the specifications themselves, and every claim names the clause it came from.

Start at chapter 1 The whole thing on one page Sit the final test Look at the document first

This course was written against TS 23.369 version 20.0.0, and built from a source register generated 2026-08-04.

Same subject, different depth: overview · in depth

The document, all of it

One block per clause of TS 23.369, in the order they appear, sized by how much text the clause holds. Lit blocks are taught in this course.

Open the whole of TS 23.369 as a page

The chapters

Part 1 What it is, and what it is made of

  1. 1 What Ambient IoT is: a network that reads tags with no battery A whole system built so a mobile network can read tags that have no battery — what it is, the four jobs it does, and the fence Release 19 drew around it. 5 min
  2. 2 What an Ambient IoT system is made of Nine parts named by the architecture document plus one piece of radio equipment — which are new, which are 5G functions given a new job, and what was deliberately left out. 5 min

Part 2 How it works, and what it does not protect

  1. 3 How a tag is actually read, from the request to the answer What happens between an application asking and a battery-less tag answering — the tone it reflects, the queue it has to win, and why every command starts with an inventory. 5 min
  2. 4 What the security protects, and what it leaves open on purpose Commands must have their integrity checked; encryption and temporary identifiers must be supported and need not be switched on. 6 min

Testing yourself

Every question at once

20 questions, chapter by chapter, on one page — for revision after you have read the course.

Open all the questions

The final test

10 questions drawn across the whole course, marked at the end. 60 per cent to pass, and every miss says which chapter to go back to.

Sit the final test

What this course is built on

Chapters
4
Words written for you
3,990
Clauses covered
25 of 128
Figures from the document
26
Abbreviations
5
Published versions
8
Checked sources
176
Sources this course cites
19

The document · Words · History · Documents around it · Every source