ISO/IEC 18000-2:2004

INTERNATIONAL ISO/IEC
STANDARD 18000-2
First edition
2004-09-15
Information technology — Radio
frequency identification for item
management —
Part 2:
Parameters for air interface
communications below 135 kHz
Technologies de l'information — Identification par radiofréquence
(RFID) pour la gestion d'objets
Partie 2: Paramètres pour les communications d'une interface d'air à
moins de 135 kHz
Reference number
©
ISO/IEC 2004
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©  ISO/IEC 2004
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ii © ISO/IEC 2004 – All rights reserved

Contents Page
Foreword. vi
Introduction . vii
1 Scope. 1
2 Conformance . 1
2.1 Tag. 1
2.2 Interrogator. 2
3 Normative references . 2
4 Terms, definitions, symbols and abbreviated terms. 2
4.1 Terms and definitions. 2
4.2 Symbols . 3
4.3 Abbreviated terms. 3
5 Physical layer . 4
5.1 Type A (FDX). 4
5.1.1 Power transfer . 4
5.1.2 Frequency . 4
5.1.3 Communication signal interface interrogator to tag . 4
5.1.4 Communication signal interface tag to interrogator . 6
5.2 Type B (HDX) . 7
5.2.1 Power transfer . 7
5.2.2 Communication signal interface interrogator to tag . 7
5.2.3 Communication signal interface tag to interrogator . 10
5.3 Physical and Media Access Control (MAC) Parameters . 11
5.3.1 Interrogator to tag link. 11
5.3.2 Tag to interrogator link. 14
6 Transmission Protocol . 16
6.1 Basic elements . 16
6.2 Unique identifier. 16
6.2.1 Unique identifier (UID) . 16
6.2.2 Sub-UID . 17
6.3 Request format. 18
6.4 Response format. 18
6.5 Request flags. 19
6.5.1 AFI flag . 20
6.5.2 NOS flag . 20
6.5.3 SEL flag and ADR flag . 20
6.5.4 CRCT flag. 20
6.5.5 PEXT flag. 21
6.6 Error flag . 21
6.7 Block security status . 21
6.8 AFI security status. 22
6.9 DSFID security status. 22
6.10 Start of frame pattern (SOF). 22
6.10.1 Interrogator request. 22
6.10.2 Tag response. 22
6.11 End of frame pattern (EOF) . 23
6.11.1 Interrogator request. 23
6.11.2 Tag response. 23
6.12 CRC. 23
6.13 Application family identifier (AFI). 23
© ISO/IEC 2004 – All rights reserved iii

6.14 Data storage format identifier (DSFID).25
7 User memory organisation.25
8 Tag states.25
8.1 Power-off state.25
8.2 Ready state .25
8.3 Quiet state .25
8.4 Selected state .26
8.5 State diagram.26
9 Anti-collision.27
9.1 Request parameters.27
9.2 Request processing by the tag.27
9.3 Explanation of anti-collision sequences.30
9.3.1 Anti-collision sequence with 1 slot .30
9.3.2 Anti-collision sequence with 16 slots .30
9.3.3 Mixed population with tags of type A and B.32
10 Commands .32
10.1 Command classification .32
10.1.1 Mandatory commands .32
10.1.2 Optional commands.32
10.1.3 Custom commands .32
10.1.4 Proprietary commands .32
10.2 Command code structure.33
10.3 Command list.34
10.4 Mandatory commands .34
10.4.1 INVENTORY.34
10.4.2 STAY QUIET .36
10.5 Optional commands.36
10.5.1 READ SINGLE BLOCK .36
10.5.2 READ SINGLE BLOCK WITH SECURITY STATUS .36
10.5.3 READ MULTIPLE BLOCKS .37
10.5.4 READ MULTIPLE BLOCKS WITH SECURITY STATUS.38
10.5.5 WRITE SINGLE BLOCK.39
10.5.6 WRITE MULTIPLE BLOCKS.39
10.5.7 LOCK BLOCK.40
10.5.8 GET SYSTEM INFORMATION.41
10.5.9 SELECT .42
10.5.10 RESET TO READY.43
10.5.11 WRITE SYSTEM DATA .43
10.5.12 LOCK SYSTEM DATA .44
10.5.13 Optional command execution in inventory mode.45
10.6 Custom commands .46
10.7 Proprietary commands .46
11 Protocol timing specifications.46
11.1 Type A (FDX).47
11.1.1 Tag waiting time before transmitting its response after reception of an EOF from the
interrogator .47
11.1.2 Interrogator waiting time before sending a subsequent request.47
11.1.3 Interrogator waiting time before switching to the next slot during an inventory process.48
11.2 Type B (HDX).49
11.2.1 Tag waiting time before transmitting its response after reception of an EOF from the
interrogator .49
11.2.2 Interrogator waiting time before sending a subsequent request.49
11.2.3 Interrogator waiting time before switching to the next slot during an inventory process.49
11.2.4 Tag charge and re-charge .50
12 Protocol parameters.50
13 Anti-collision parameters .51
iv © ISO/IEC 2004 – All rights reserved

Annex A (informative) CRC Check for Error Detection. 53
A.1 Description. 53
A.2 CRC check source code example . 54
Annex B (informative) Alternative carrier frequency for Type B operating fields . 55
B.1 Description. 55
Annex C (informative) Description of a typical anti-collision sequence with tags of types A and B . 56
C.1 Description. 56
Annex D (informative) Optional anti-collision mechanism. 57
D.1 Introduction . 57
D.2 Description. 57
D.3 Physical layer for the Multi-read command. 57
D.3.1 Power transfer . 58
D.3.2 Frequency . 58
D.3.3 Interrogator to tag . 58
D.3.4 Tag to interrogator . 58
D.3.5 Parameters for optional Multi-read command . 59
D.4 Multi-read command . 61
D.4.1 Multi-read request format. 61
D.4.2 Request flags. 61
D.5 Anti-collision mechanism. 62
D.5.1 Acknowledgement by the interrogator .62
D.5.2 Acknowledgement by the tag . 63
D.5.3 Timing. 63
D.5.4 Explanation of an anti-collision sequence .63
D.6 Protocol and anti-collision Parameters . 69
D.6.1 Protocol Parameters. 69
D.6.2 Anti-collision Protocol. 70

© ISO/IEC 2004 – All rights reserved v

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
ISO/IEC 18000-2 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 31, Automatic identification and data capture techniques.
ISO/IEC 18000 consists of the following parts, under the general title Information technology — Radio
frequency identification for item management:
 Part 1: Reference architecture and definition of parameters to be standardized
 Part 2: Parameters for air interface communications below 135 kHz
 Part 3: Parameters for air interface communications at 13,56 MHz
 Part 4: Parameters for air interface communications at 2,45 GHz
 Part 6: Parameters for air interface communications at 860 MHz to 960 MHz
 Part 7: Parameters for active air interface communications at 433 MHz

vi © ISO/IEC 2004 – All rights reserved

Introduction
ISO/IEC 18000 is a series of International Standards describing common communications protocols for the
purpose of Radio Frequency Identification for Item Management.
This part of ISO/IEC 18000 relates to systems operating at frequencies less than 135 kHz.
It has been developed in accordance with the requirements determined in ISO 18000-1, Information
technology — Radio frequency identification for item management — Reference architecture and definition of
parameters to be standardized.
The International Organization for Standardization (ISO) and International Electrotechnical Commission (IEC)
draw attention to the fact that it is claimed that compliance with this document may involve the use of patents
concerning radio-frequency identification technology given in the table below.
ISO and IEC take no position concerning the evidence, validity and scope of these patent rights.
The holders of these patent rights have assured the ISO and IEC that they are willing to negotiate licences
under reasonable and non-discriminatory terms and conditions with applicants throughout the world. In this
respect, the statements of the holders of these patent rights are registered with ISO and IEC.
Information may be obtained from:
Contact details Patent number
ATMEL US 5286955
Dr. Bertram Koch EP 0502518B1
Leiter Patentabteilung OP31
ATMEL Germany GmbH
Theresienstrasse 2
D-74072 Heilbronn
Germany
Tel: +49-7131-67-3254
Fax: +49-7131-67-2789
bertram.koch@hno.atmel.com
Matrics Technology US 6002344
Mr Kevin J Powell
Senior Director, Product Development
8850 Stanford Blvd, Suite 3000
Columbia, MD 21045
USA
Tel: +1-410-872-0300
Fax +1-443-782-0230
kpowell@matrics.com
Koninklijke Philips Electronics N.V AT-PS 401127, CN 1293789-A
Mr.Harald Röggla EP 1064616A, JP 00-596516
Intellectual Property & Standards US 09/487151, WO 00/45328-A1
Triester Strasse 64 EP 0473569B, JP A91-211035
A-1101 Vienna US 5345231B, AT-PS 395224
Austria US 2002-0131453-A1
harald.roeggla@philips.com WO 02/073511
© ISO/IEC 2004 – All rights reserved vii

Contact details Patent number
INTERCODE / SPACECODE US 5426423, EP 90909459.1
12, Rue des Petits Ruisseaux CA 2058 947, US 6177858B1
Z.I. des Godets EP 96402556.3, CA 2191787
F-91370 Verrières le Buisson US 5923251, EP 96402554.8
France CA 21911788, US 5808550
Tel: + 33.1.69.75.21.70 EP 96402555.5, CA 2191794
Fax: + 33.1.60.11.00.31
intercode.sarl@wanadoo.fr
Texas Instruments Inc. EP 845751, US 5793324
Mr. Russ Baumann US 5929801, US 5053774
S&C Patent & Legal Counsel
34 Forest Street
Attleboro, MA
USA
Tel:  +1 508-236-3314
Fax: +1 508-236-1960
rbaumann@ti.com
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights other than those identified above. ISO and IEC shall not be held responsible for identifying any or all
such patent rights.
viii © ISO/IEC 2004 – All rights reserved

INTERNATIONAL STANDARD ISO/IEC 18000-2:2004(E)

Information technology — Radio frequency identification for
item management —
Part 2:
Parameters for air interface communications below 135 kHz
1 Scope
This part of ISO/IEC 18000 defines the air interface for radio frequency identification (RFID) devices operating
below 135 kHz used in item management applications. Its purpose is to provide a common technical
specification for RFID devices to allow for compatibility and to encourage inter-operability of products for the
growing RFID market in the international marketplace. This part defines the forward and return link
parameters for technical attributes including, but not limited to, operating frequency, operating channel
accuracy, occupied channel bandwidth, spurious emissions, modulation, duty cycle, data coding, bit rate, bit
rate accuracy, bit transmission order. It further defines the communications protocol used in the air interface.
This part contains two types. The detailed technical differences between the types are shown in the parameter
tables.
This part of ISO/IEC 18000 specifies
• The physical layer that is used for communication between the interrogator and the tag.
• The protocol and the commands
• The method to detect and communicate with one tag among several tags (“anti-collision”)
It specifies two types of tags: Type A (FDX) and Type B (HDX). These two types differ only by their physical
layer. Both types support the same anti-collision and protocol.
FDX tags are permanently powered by the interrogator, including during the tag-to-interrogator transmission.
They operate at 125 kHz.
HDX tags are powered by the interrogator, except during the tag-to-interrogator transmission. They operate at
134,2 kHz. An alternative operating frequency is described in Annex B.
An optional anti-collision mechanism is described in Annex D.
2 Conformance
2.1 Tag
To claim conformance with this part of ISO/IEC 18000, a tag shall be of either Type A or B.
NOTE Nothing in this part of ISO/IEC 18000 prevents a tag to be of both types, although for technical reasons, it is
unlikely that such tags are ever marketed.
© ISO/IEC 2004 – All rights reserved 1

2.2 Interrogator
To claim conformance with this part of ISO/IEC 18000, an interrogator shall support both Types A and B.
Depending on the application, it may be configured as Type A only, Type B only or Types A and B.
When configured in Types A and B, and when in the Inventory phase, the interrogator shall alternate between
Type A and Type B interrogation. See Annex C.
NOTE The rules for RFID device (tag and interrogator) conformity evaluation will be given in a future Technical
Report (ISO/IEC TR 18047-2).
3 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO/IEC 7816-6, Identification cards — Integrated circuit cards — Part 6: Interindustry data elements for
interchange
ISO/IEC 15418, Information technology — EAN/UCC Application Identifiers and Fact Data Identifiers and
Maintenance
ISO 11784, Radio frequency identification of animals — Code structure
ISO 11785, Radio frequency identification of animals — Technical concept
ISO/IEC 15961, Information technology — Radio frequency identification for item management — Data
1)
protocol: application interface
ISO/IEC 15962, Information technology — Radio frequency identification for item management — Data
1)
protocol: data encoding rules and logical memory functions
ISO/IEC 18000-1, Information technology — Radio frequency identification for item management — Part 1:
Reference architecture and definition of parameters to be standardized
ISO/IEC 19762 (all parts), Information technology — Automatic identification and data capture techniques —
1)
Harmonized vocabulary
4 Terms, definitions, symbols and abbreviated terms
For the purposes of this document, the terms, definitions, symbols and abbreviated terms given in
ISO/IEC 19762 (all parts) and the following apply.
4.1 Terms and definitions
4.1.1
anti-collision loop
algorithm used to prepare for and handle a dialogue between interrogator and one or more tags out of several
in its energizing field
4.1.2
byte
8 bits of data designated b1 to b8, from the most significant bit (MSB, b8) to the least significant bit (LSB, b1)

1) To be published.
2 © ISO/IEC 2004 – All rights reserved

4.2 Symbols
All symbols are expressed with a letter, followed by a upper case letter (A or B or D when referring
respectively to the Type A or Type B or Annex D, p when referring to the protocol), followed by letters and/or
numbers as appropriate. The main symbols are listed below, where X represents A or B or D. Timings are
expressed with an upper case T and according to above rule. Other symbols specific to A, B or D are
specified in the relevant clauses.
f Carrier frequency of the operating field
Xc
T Period of Data Symbol "0"
Xd0
T Period of Data Symbol "1"
Xd1
T Period of carrier frequency (T = 1/f )
Xc Xc Xc
T Code Violation Duration
Xcv
4.3 Abbreviated terms
ACL Allocation class
ASK Amplitude shift keying
AFI Application family identifier
BSS Block security status
BWP Block write protection
CRC Cyclic redundancy check
CRCT Response cyclic redundancy check flag
DSFID Data storage format identifier
EOF End of frame
FDX Full duplex
HDX Half duplex
IRC IC reference code
LSB Least significant bit
MFC Manufacturer code
MSB Most significant bit
MSN Manufacturer serial number
NOB Number of blocks
NOS Number of slots
NRZ Non return to zero
RF Radio frequency
RFU Reserved for future use
SOF Start of frame
SUID Sub unique identifier (includes MFC and MSN)
UID Unique Identifier (includes ACL, MFC and MSN)
© ISO/IEC 2004 – All rights reserved 3

5 Physical layer
5.1 Type A (FDX)
5.1.1 Power transfer
Power transfer to the tag is accomplished by radio frequency via coupling antennas in the tag and in the
interrogator. The RF operating field supplies permanently power from the interrogator to the FDX tag. For
communication between interrogator and tag, the field is modulated.
5.1.2 Frequency
The carrier frequency of the RF operating field is f = 125 kHz.
Ac
5.1.3 Communication signal interface interrogator to tag
5.1.3.1 Modulation
Communications between interrogator and tag takes place using ASK modulation with a modulation index of
100%.
T
A1
T T
A2 A3
y
y
a
x
b
y
t
envelope of interrogation field

Figure 1 — Modulation details of data transmission from interrogator to tag

Table 1 — Modulation coding times
Min Max
m = (a-b)/(a+b) 90 % 100 %
T 4 * T 10 * T
A1 Ac Ac
T 0 0,5 * T
A2 A1
T 0 0,5 * T
A3 Ad0
x 0 0,15 * a
y 0 0,05 * a
NOTE T = 1/f ≈ 8µs
Ac Ac
4 © ISO/IEC 2004 – All rights reserved

RF Carrier Amplitude
5.1.3.2 Data rate and data coding
The interrogator-to-tag communication uses Pulse interval encoding. The interrogator creates pulses by
switching the carrier as described in Figure 1. The time between the falling edges of the pulses determines
either the value of the data bit "0" and "1", a Code violation or a Stop condition.
Assuming equal distributed data bits "0" and "1", the data rate is in the range of 5,1 kbit/s.
Data “0”
T
Ad0
T T
Ap Ap
carrier on
carrier off
Data “1”
T
Ad1
T
Ap T
Ap
carrier on
carrier off
“Code violation”
T
Acv
T
Ap T
Ap
carrier on
carrier off
“Stop condition”
T
Acf
T
Ap
carrier on
carrier off
Figure 2 — Interrogator to tag: Pulse interval encoding

Table 2 — Data coding Times
Meaning Symbol
min max
"Carrier off" time T 4 * T 10 * T
Ap Ac Ac
Data "0" time T 18 * T 22 * T
Ad0 Ac Ac
Data "1" time T 26 * T 30 * T
Ad1 Ac Ac
"Code violation" time T 34 * T 38 * T
Acv Ac Ac
"Stop condition" time T ≥ 42 * T n/a
Asc Ac
NOTE T = 1/f ≈ 8 µs.
Ac Ac
5.1.3.3 Start of frame pattern
The interrogator request starts always with a Start of frame pattern (SOF) for ease of synchronization. The
SOF pattern consists of a data bit "0" pattern and a "Code violation" pattern.
© ISO/IEC 2004 – All rights reserved 5

Data “0”
“Code violation”
TAd0 TAcv
TAp TAp TAp
carrier on
carrier off
SOF
Figure 3 — Start of frame pattern
The tag shall be ready to receive a SOF from the interrogator within 1,2 ms after having sent a response to
the interrogator.
The tag shall be ready to receive a SOF from the interrogator within 2,5 ms after the interrogator has
established the powering field.
5.1.3.4 End of frame pattern
For slot switching during a multislot anti-collision sequence, the interrogator request is an EOF pattern. The
EOF pattern is represented by a "Stop condition".
“Stop condition”
T
Asc
T
Ap
carrier on
carrier off
EOF
Figure 4 — End of frame pattern
5.1.4 Communication signal interface tag to interrogator
5.1.4.1 Data rate and data coding
The tag shall be capable to communicate with the interrogator via an inductive coupling, whereby the carrier is
loaded with
- a 4 kbit/s Manchester coded data signal on the International Standard commands
- a 2 kbit/s dual pattern data coding on the INVENTORY command

NOTE The slower data rate used during the inventory process allows for improving the collision detection when
several tags are present in the interrogator field, especially if some tags are in the near field and others in the far field.

6 © ISO/IEC 2004 – All rights reserved

International Standard
Data Element Inventory command
command
T T
T
Ad Ad Ad
load off load off
Data "0"
load on
load on
T T T
Ad Ad Ad
load off load off
Data "1"
load on load on
Figure 5 — Tag to interrogator: load modulation coding
5.1.4.2 Start of frame pattern
The tag response starts always with a Start of frame (SOF) pattern. The SOF pattern is a Manchester coded
bit sequence of "110".
Data “1” Data “1” Data “0”
T
T T
Ad Ad Ad
load off
load on
Figure 6 — Start of frame pattern
5.1.4.3 End of frame pattern
No EOF is used nor specified for the tag response.
5.2 Type B (HDX)
5.2.1 Power transfer
Power transfer to the tag is accomplished by radio frequency via coupling antennas in the tag and in the
interrogator. The RF operating field supplies power at the beginning of the request from the interrogator to the
HDX tag. For communication between interrogator and tag, the field is modulated.
5.2.1.1 Frequency
The carrier frequency of the RF operating field is f = 134,2 kHz or as described in Annex B.
Bc
5.2.2 Communication signal interface interrogator to tag
5.2.2.1 Modulation
Communication between interrogator and tag takes place using ASK modulation with a modulation index of
100%.
© ISO/IEC 2004 – All rights reserved 7

T
B1
T T
B2 B3
y
y
a
x b
y
t
envelope of interrogation field

Figure 7 — Modulation details of data transmission from interrogator to tag

Table 3 — Modulation coding times
Fast data rate Slow data rate
Symbol
min nom max min nom max
T 11 * T 13* T 18 * T 11 * T 13* T 25 * T
B1 Bc Bc Bc Bc Bc Bc
T 2 * T 7 * T 10 * T 2 * T 7 * T 10 * T
B2 Bc Bc Bc Bc Bc Bc
T 5 * T 25 * T 32 * T 5 * T 100 * T 115 * T
B3 Bc Bc Bc Bc Bc Bc
x 0 n/a 0,15 * a 0 n/a 0,15 * a
y 0 n/a 0,05 * a 0 n/a 0,05 * a

5.2.2.2 Data rate and data coding
The interrogator-to-tag communication uses Pulse interval encoding. The interrogator creates pulses by
switching the carrier as described in Figure 7. The time between the falling edges of the pulses determines
either the value of the data bit "0" and "1", a Code violation or a Stop condition.
Assuming equal distribution of data bits “0” and “1”, the data rates are:
Slow data rate: 1 kbit/s
Fast data rate: 2,3 kbit/s.
8 © ISO/IEC 2004 – All rights reserved

RF Carrier Amplitude
T
Bd0
carrier on
Data
carrier off
“0”
T
Bd1
carrier on
Data
carrier off
“1”
T
Bcv
carrier on
Code violation
carrier off
Figure 8 — Interrogator to tag: modulation and coding
Table 4 — Data coding times
Fast data rate Slow data rate
Symbol
min nom Max min nom max
T 42 * T 47 * T 52 * T 110 * T 120 * T 130 * T
Bd0 Bc Bc Bc Bc Bc Bc
T 62 * T 67 * T 72 * T 140 * T 150 * T 160 * T
Bd1 Bc Bc Bc Bc Bc Bc
T 175 * T 180 * T 185 * T 200 * T 210 * T 220 * T
Bcv Bc Bc Bc Bc Bc Bc
NOTE T =1/f ≈ 7,452 µs
Bc Bc
5.2.2.3 Start of frame pattern
The interrogator request starts always with a Start of frame (SOF) pattern. The SOF pattern consists of Data
"1", Data "0" and "Code violation" pattern that define a clear start of frame. The difference in duration as
specified in Table 4 informs the tag about the requested data rate.
T T T
B1 B0 Bcv
carrier on
carrier off
Figure 9 — Start of frame pattern

5.2.2.4 End of frame
The EOF of an interrogator request is defined as the falling edge of the field followed by a delay time longer
than T .
B1
For the 16 slots inventory sequence, the EOF that instructs the tags to switch to the next slot is defined as the
rising edge of the interrogator field followed by a time t .
RCH
In both cases, the tag shall receive this sequence before transmitting its response SOF.
© ISO/IEC 2004 – All rights reserved 9

5.2.3 Communication signal interface tag to interrogator
5.2.3.1 Data rate and data coding
The tag shall be capable to communicate with the interrogator via an inductive coupling, whereby the power is
switched off and the data are FSK modulated using the frequencies:
- f = 134,2 kHz for the “Low Bit” encoding
Bc
- f = 123,7 ± 4,2 kHz for the “High Bit” encoding
B1
The data coding is based on the NRZ method.
The average data rate is 8 kbit/s.
International Standard
Data Element Comment
command
TBd0
Data "0"
T = 16/f
Bd0 Bc
fc
TBd_1
Data "1" T = 16/f
Bd1 B1
f1
Figure 10 — Tag to interrogator: modulation and coding
5.2.3.2 Start of frame pattern
The tag response starts always with a Start of frame (SOF) pattern. The SOF pattern is coded with a bit
pattern of "111101".
f represents the frequency for data bit “1” (T ) and f for data bit “0” (T ).
B1 Bd1 Bc Bd0
Data Bits
f1 f1 f1 f1 fc f1
Bit Coding
SOF
Figure 11 — Start of frame pattern

5.2.3.3 End of frame pattern
The tag response ends always with an End of frame (EOF) pattern. The EOF pattern is coded with a bit
pattern of "101111".
f represents the frequency for data bit “1” (T ) and f for data bit “0” (T ).
B1 Bd1 Bc Bd0
10 © ISO/IEC 2004 – All rights reserved

Data Bits
f1 fc f1 f1 f1 f1
Bit Coding
EOF
Figure 12 — End of frame pattern
5.3 Physical and Media Access Control (MAC) Parameters
5.3.1 Interrogator to tag link
Ref. Parameter Description Type A Description Type B Options/Comments
Operating
M1-INT: 1
One interrogator to tag One interrogator to tag
Frequency Range
link channel at 125 kHz link channel at 134,2 kHz

Default Operating
M1-INT: 1a 125 kHz
134,2 kHz
Frequency
Operating
M1-INT: 1b
Channels
Not appropriate for this MODE
(for Spread
Spectrum
systems)
Operating
M1-INT: 1c
Frequency
Within ± 0,1 kHz
Accuracy
Frequency Hop
M1-INT: 1d
Rate
Not appropriate for this MODE
(for Frequency
Hopping [FHSS]
systems)
Frequency Hop
M1-INT: 1e
Sequence
Not appropriate for this MODE
(for Frequency
Hopping [FHSS]
systems)
Occupied Channel
M1-INT: 2
3 dB Bandwidth
± 4 kHz ± 8 kHz
Bandwidth
Minimum Receiver
M1-INT: 2a 3 dB Bandwidth
± 10 kHz ± 8 kHz
Bandwidth
Interrogator
M1-INT: 3 @ d = 10m
Transmit
see ITUR 012E-WB9
Maximum EIRP
65,5 dBµA/m
Power Limits
within
Communication
Zone
Interrogator
M1-INT: 3 @9 kHz descending
Transmit Spurious
27 dBµA/m 3dB/octave, until 10
Emissions
MHz
© ISO/IEC 2004 – All rights reserved 11

Ref. Parameter Description Type A Description Type B Options/Comments
Interrogator
M1-INT: 4a
Transmit Spurious
Emissions, In-
Band
Not appropriate for this MODE
(for Spread
Spectrum
systems)
Interrogator
M1-INT: 4b
Transmit Spurious
See M1A-F3
Emissions, Out-of-
Band
Interrogator
M1-INT: 5 Emissions below 135 kHz 65,5 dBµA/m @ f<135kHz
Transmitter
65,5 dBµA/m @ f<135kHz 50 dBµA/m @ f<135-
Spectrum Mask
140kHz
30 dBµA/m @ f<140-
148,5kHz
Timing
M1-INT: 6
Transmit to
M1-INT: 6a Interrogator has to
Receive Turn
wait min. 1,2 ms
Around Time
before sending next
1,2 ms
command
Receive to
M1-INT: 6b Interrogator has to
Transmit Turn
wait min 2 ms for
Around Time
2 ms answer of tag before
signalizing a timeout
error.
Dwell Time or
M1-INT: 6c
Interrogator
< 2 ms < 2ms
Transmit Power
On Ramp
Decay Time or
M1-INT: 6d
Interrogator
No
...