RFID, NFC & UWB · Study deck

RFID Standards and Protocols

Picture a warehouse tag that one reader sees but another cannot decode.

Radio Remi is your guide for this deck.

rfidstandardsepc-gen2

Radio Remi, the module guide, in a scene from this chapter.

After studying this chapter

Learning objectives

You will be able to:

Separate air-interface standards from reader-control protocols and event-data standards.
Choose between ISO 14443, ISO 15693, EPC Gen2, NFC Forum, and active RFID families based on workflow evidence.
Explain why EPC Gen2 anti-collision needs a tuned inventory round instead of only higher reader power.
Describe how EPC identifiers become useful business events through middleware, EPCIS, and common vocabularies.

Major section

Start With the Story

Both boxes say they support tags, yet the air link, reader control, and event record may follow different contracts.

Near field communication, or NFC, is a short-range radio method for nearby exchanges.
Radio frequency means the rate of a radio wave.
Radio frequency identification, or RFID, uses radio to identify a tag.

Major section

Start With the Story (continued)

Standards divide that work into layers that must not be confused.

Swap one reader and reject any event whose meaning changes.
This runway does not make one standards family fit every workflow.
A working RFID system has several contracts at once.
This chapter separates those contracts so design reviews do not mix them together.

Major section

Why Standards Matter

EPC, EPCIS, and the GS1 Core Business Vocabulary describe how identifiers and read events are represented for supply-chain visibility.

LLRP or an SDK controls reader operations and device settings.
A tag ID read at the air interface does not yet supply that event context.

RFID standards grouped by responsibility: air interface, NFC behavior, reader control, and event sharing

Major section

Event-Data Standards

The Electronic Product Code gives physical things a structured identifier.

EPCIS and the Core Business Vocabulary help turn observations into shareable events such as what was observed, where it was observed, when it happened, and why it matters to the business process.
This distinction is important.
The event layer needs business context and reviewable evidence.

Major section

EPC Gen2 Dominates UHF Supply-Chain RFID

Picking a standard is really picking a band, range class, interaction pattern, and evidence model together.

It defines radio behavior between reader and tag plus the tag data conventions that let a Gen2 reader from one vendor inventory Gen2 tags from another.
The other standards fill in the interaction patterns Gen2 does not cover.
The important design habit is to keep the standards family tied to the interaction that must be proven.

Major section

EPC Gen2 Dominates UHF Supply-Chain RFID (continued)

ISO/IEC 14443 supports proximity behavior at 13.56 MHz HF: ISO/IEC 15693 supports vicinity behavior at 13.56 MHz HF, and: ISO 11784/11785 covers LF animal identification at 134.2 kHz.

A medicine cabinet badge tap is not the same problem as a dock-door carton portal.
In the cabinet case, the review evidence may say: staff presents a badge within a few centimeters, the cabinet logs one deliberate access event, and a missed read sends the nurse to a manual identity check.
That points toward EPC Gen2 UHF because bulk inventory and anti-collision are the central mechanisms.

Major section

Choosing A Standards Family

A deliberate phone or card tap suggests a close HF workflow, while a portal or bulk inventory needs a different zone and tag motion test.

ISO air-interface or EPC family names describe parts of the technology, but the installed object, read pattern, and application event determine whether a candidate fits.

RFID standard selection lanes for tap, vicinity, bulk portal, and active asset workflows

Major section

Folded Standards Selection Record

The pilot then moves representative mounted objects through real paths and records successful, false, duplicate, and missed reads.

Its retest trigger makes later material, reader, tag, or workflow changes reopen the evidence instead of inheriting an outdated standards decision.

Major section

EPC Gen2 Anti-Collision

When many passive tags are energized at the same time, they cannot all answer at once.

EPC Gen2 uses a slotted process where the reader announces a Q value, tags choose slots, and collided tags retry in later rounds.
A singleton can yield one tag reply, a collision needs another opportunity, and an empty slot carries no tag.

EPC Gen2 inventory round showing reader Q value, tag slot choice, successful slots, empty slots, and collision retry

Major section

Q Value As A Planning Heuristic

A larger Q reduces collisions but lengthens a round.

The slot count is 2^Q.
That estimate is only a starting point.
A smaller Q shortens a round but increases collisions.
The best setting depends on dwell time, tag count, antenna sequence, reader firmware, and the materials in the read zone.

Major section

The Select, Query, And ACK Handshake

If it starts at Q = 9, there are 512 slots, so the round can waste time stepping through mostly empty slots.

Getting Q close to the population size is what separates a fast inventory from a stalled one.
If a dock-door reader expects about 48 tags in the field, ceil(log2(48)) = 6, so Q = 6 gives 2^6 = 64 slots.
Both extremes can lose reads when the pallet is moving.

Major section

From Identifier To Business Event

A standards-compliant read is still just an observation.

The system becomes useful when the observation is filtered, associated with business context, and shared in a form that other systems can interpret.
Reader, antenna, time, zone, and filter fields state where and how it was seen.

RFID data path from tag identifier to reader, middleware filtering, EPCIS event, and business application

Major section

Gen2 Memory Banks Are Separate Evidence Fields

Reading a Gen2 tag well means knowing where its data lives.

Reserved holds access controls.
EPC is the main writable identifier, TID may help identify the chip, and User memory holds optional data.
An EPC can be copied.

Gen2 tag memory banks showing reserved controls, EPC, TID, and user memory

Major section

Checkpoint: Concept Relationships

Frequency-band knowledge explains why LF, HF, UHF, and active systems behave differently.

Tag-type knowledge explains why passive, battery-assisted, and active tags fit different workflows.
RFID security knowledge explains why range, identity, and event sharing create privacy and misuse risks.
Deployment knowledge explains how antenna placement, reader scheduling, and exception handling affect the final outcome.

Deck summary

Key takeaways

Both boxes say they support tags, yet the air link, reader control, and event record may follow different contracts.

Standards divide that work into layers that must not be confused.
EPC, EPCIS, and the GS1 Core Business Vocabulary describe how identifiers and read events are represented for supply-chain visibility.
The Electronic Product Code gives physical things a structured identifier.
Picking a standard is really picking a band, range class, interaction pattern, and evidence model together.

Retrieval practice

Recall check 1 of 3

Radio Remi says: answer from memory, then check your reasoning.

Q1A team is choosing an RFID or NFC standards family early in design. Which evidence packet is strong enough to make the choice reviewable?

AA frequency-only note that says 13.56 MHz means phone compatibility.

BA power-tuning plan that omits the workflow, standard family, and event schema.

CA tag-read demo with no standard, settings, privacy, schema, or retest record.

DA workflow packet with range, environment, standards layer, event owner, and pilot evidence.

Show answer

Answer: D A reviewable RFID standards choice ties the workflow, object, interaction range, environment, standards family, reader-control layer, event-data layer, pilot evidence, privacy and operations risks, and retest trigger together.

Retrieval practice

Recall check 2 of 3

Radio Remi says: answer from memory, then check your reasoning.

Q2A hospital wants staff to intentionally tap a badge at a medication cabinet, while the same hospital also wants bulk inventory reads of tagged supply cases at a receiving doorway. What is the best standards decision?

AUse proximity standard at cabinet; test UHF at receiving.

BUse EPC Gen2 UHF for both to share readers and tag inventory.

CUse ISO 15693 for both to keep the read zones close to staff.

DSkip air interfaces and standardize only on the EPCIS event layer.

Show answer

Answer: A Standards choices should follow the workflow.

Retrieval practice

Recall check 3 of 3

Radio Remi says: answer from memory, then check your reasoning.

Q3A brand-protection application checks for copied EPC identifiers on UHF tags. Which Gen2 memory should it compare with the EPC, and why?

AThe EPC bank, because its identifier matches the brand's inventory record.

BThe factory-locked TID serial, checked beside the writable EPC.

CThe access password, because only genuine tags can carry passwords.

DThe User bank, because writable application data proves origin.

Show answer

Answer: B Gen2 defines Reserved, EPC, TID, and User banks.

Print reference

Answers

Answer key.

D · A reviewable RFID standards choice ties the workflow, object, interaction range, environment, standards family, reader-control layer, event-data layer, pilot evidence, privacy and operations risks, and retest trigger together.
A · Standards choices should follow the workflow.
B · Gen2 defines Reserved, EPC, TID, and User banks.