ISO/IEC 24730-5:2010
(Main)Information technology — Real-time locating systems (RTLS) — Part 5: Chirp spread spectrum (CSS) at 2,4 GHz air interface
Information technology — Real-time locating systems (RTLS) — Part 5: Chirp spread spectrum (CSS) at 2,4 GHz air interface
ISO/IEC 24730 defines air interface protocols and an application programming interface (API) for real-time locating systems (RTLS). ISO/IEC 24730-5:2010 defines an air interface protocol which utilizes chirp spread spectrum (CSS) at frequencies from 2,4 GHz to 2,483 GHz. This protocol supports bidirectional communication and two-way ranging between the readers and tags of an RTLS. The mandatory default mode ensures interoperability between tags and infrastructure from various manufacturers, while the availability of several options offers flexibility to the developer of the infrastructure to adapt the behaviour of the overall system to the specific needs of his application.
Technologies de l'information — Systèmes de localisation en temps réel (RTLS) — Partie 5: Spectre étalé de compression d'impulsions (CSS) à une interface d'air de 2,4 GHz
General Information
Standards Content (Sample)
INTERNATIONAL ISO/IEC
STANDARD 24730-5
First edition
2010-04-01
Information technology — Real-time
locating systems (RTLS) —
Part 5:
Chirp spread spectrum (CSS) at 2,4 GHz
air interface
Technologies de l'information — Systèmes de localisation en temps réel
(RTLS) —
Partie 5: Spectre étalé de compression d'impulsions (CSS) à une
interface d'air de 2,4 GHz
Reference number
ISO/IEC 24730-5:2010(E)
©
ISO/IEC 2010
---------------------- Page: 1 ----------------------
ISO/IEC 24730-5:2010(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.
COPYRIGHT PROTECTED DOCUMENT
© ISO/IEC 2010
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO/IEC 2010 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/IEC 24730-5:2010(E)
Contents Page
Foreword .vi
Introduction.vii
1 Scope.1
2 Normative references.1
3 Terms and definitions .2
4 Symbols and abbreviated terms .3
5 Overview.6
5.1 Components.6
5.2 Purpose .6
5.3 Not covered by the standard.7
5.4 System.7
5.5 Document structure .7
6 Requirements.7
6.1 Frequency range.7
6.2 2,4 GHz spread spectrum air interface specifications.7
6.3 Compliance requirements .8
6.4 Manufacturer tag ID.8
6.5 Physical layer parameters .8
7 Physical (PHY) layer specification.9
7.1 Modulations .9
7.2 Data rates .9
7.2.1 General PHY packet format .9
7.3 2-ary orthogonal CSS.9
7.3.1 Reference modulator diagram .10
7.3.2 Bandwidths and Transmit power spectral density (PSD) mask .10
7.3.3 Equivalent baseband representation of the continuous time 2-ary orthogonal CSS signal .12
7.3.4 Signal tolerance.13
7.3.5 Bit to symbol mapping.13
7.3.6 Chirp generator.13
7.3.7 Preamble.13
7.3.8 Start of frame delimiter .14
7.3.9 Bit scrambler.14
7.3.10 PHY Header .14
7.3.11 Overview (informative).14
7.4 DQPSK-CSS .16
7.4.1 Reference modulator diagram .16
7.4.2 Bandwidth and transmit Power Spectral Density (PSD) mask .17
7.4.3 Equivalent baseband representation of the continuous time DQPSK-CSS signal.18
7.4.4 Signal tolerance.20
7.4.5 Overview (informative).20
7.4.6 Demultiplexer (DEMUX) .22
7.4.7 Serial to Parallel mapping (S/P) .22
7.4.8 Data Symbol - to - Bi-Orthogonal code word mapping .22
7.4.9 Parallel - to - Serial converter (P/S) and QPSK symbol mapping.25
7.4.10 Differential-QPSK (DQPSK) coding .25
7.4.11 DQPSK to DQPSK-CSS modulation .26
7.4.12 Chirp generator.26
7.4.13 Bit interleaver.26
© ISO/IEC 2010 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO/IEC 24730-5:2010(E)
7.4.14 Preamble.26
7.4.15 Start of frame delimiter .27
7.4.16 PHY Header .27
8 MAC sub-layer specification.27
8.1 Overview.27
8.2 General packet format.27
8.3 Packet types.27
8.4 MAC frame formats.28
8.4.1 MAC frame format for Data packet.28
8.4.2 MAC frame format for ACK packet.28
8.4.3 MAC frame format for Broadcast packet.28
8.4.4 MAC frame format for RTS packet .29
8.4.5 MAC frame format for CTS packet .29
8.4.6 MAC frame fields.29
8.5 MAC Timing.31
8.5.1 2-way handshake .31
8.5.2 3-way handshake .32
8.5.3 Ranging-related time measurements.33
8.5.4 Media access.33
9 Tag application layer specification.36
9.1 Overview.36
9.1.1 Example scenario .37
9.2 Tag application states .38
9.2.1 Default state .38
9.2.2 Wait state .38
9.2.3 Range state.39
9.2.4 Sleep state .39
9.2.5 Blink state.39
9.2.6 State transitions.40
9.3 Commands .41
9.3.1 SwitchState command .42
9.3.2 SetConfigVector command.45
9.3.3 GetConfigVector command .47
9.3.4 SetRangingPeers command.47
9.3.5 AddRangingPeers command.47
9.3.6 GetRangingPeers command.48
9.3.7 User defined command .48
9.3.8 Command prioritization .48
9.4 Tag application packet formats.49
9.4.1 Application blink packet .50
9.4.2 Application command packet.51
9.4.3 Application report packet .51
9.4.4 GetConfigVector report.52
9.4.5 GetRangingPeers report .52
9.4.6 Ranging report .52
9.4.7 Application ranging packet.53
9.5 Ranging packet exchanges .57
9.5.1 Ranging packet exchange type 1.57
9.5.2 Ranging packet exchange type 2.58
9.5.3 Ranging packet exchange type 3.60
9.5.4 Ranging packet exchange type 4.61
9.6 Timing values.62
9.7 Default profile.62
9.8 Error handling .62
Annex A (informative) Time base tolerances in two-way ranging.63
Annex B (informative) Coexistence.66
Annex C (informative) Computing location values from range values.69
iv © ISO/IEC 2010 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/IEC 24730-5:2010(E)
Annex D (informative) Location and roaming of tags .70
Bibliography.72
© ISO/IEC 2010 – All rights reserved v
---------------------- Page: 5 ----------------------
ISO/IEC 24730-5:2010(E)
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.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 24730-5 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 31, Automatic identification and data capture techniques.
ISO/IEC 24730 consists of the following parts, under the general title Information technology — Real-time
locating systems (RTLS):
⎯ Part 1: Application program interface (API)
⎯ Part 2: 2,4 GHz air interface protocol
⎯ Part 5: Chirp spread spectrum at 2,4 GHz air interface
vi © ISO/IEC 2010 – All rights reserved
---------------------- Page: 6 ----------------------
ISO/IEC 24730-5:2010(E)
Introduction
CSS is a technique for spreading the bandwidth of a digital signal by using chirp pulses. Chirp pulses are
pulses with a monotonically increasing or decreasing instantaneous frequency. Chirp pulses were originally
used for radar applications. Recently, systems and standards have been developed which use chirp pulses
also for communication applications. This part of ISO/IEC 24730 includes ranging and bidirectional
communication between tags and infrastructure. Bidirectional communication enables the infrastructure to
control the behaviour of tags in a timely manner.
© ISO/IEC 2010 – All rights reserved vii
---------------------- Page: 7 ----------------------
INTERNATIONAL STANDARD ISO/IEC 24730-5:2010(E)
Information technology — Real-time locating systems (RTLS) —
Part 5:
Chirp spread spectrum (CSS) at 2,4 GHz air interface
1 Scope
ISO/IEC 24730 defines air interface protocols and an application programming interface (API) for real-time
locating systems (RTLS). This part of ISO/IEC 24730 defines an air interface protocol which utilizes chirp
spread spectrum (CSS) at frequencies from 2,4 GHz to 2,483 GHz. This protocol supports bidirectional
communication and two-way ranging between the readers and tags of an RTLS. The mandatory default mode
ensures interoperability between tags and infrastructure from various manufacturers, while the availability of
several options offers flexibility to the developer of the infrastructure to adapt the behaviour of the overall
system to the specific needs of his application.
2 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 15963, Information technology — Radio frequency identification for item management — Unique
identification for RF tags
ISO/IEC 19762-1, Information technology — Automatic identification and data capture (AIDC) techniques —
Harmonized vocabulary — Part 1: General terms relating to AIDC
ISO/IEC 19762-3, Information technology — Automatic identification and data capture (AIDC) techniques —
Harmonized vocabulary — Part 3: Radio frequency identification (RFID)
ISO/IEC 19762-4, Information technology — Automatic identification and data capture (AIDC) techniques —
Harmonized vocabulary — Part 4: General terms relating to radio communications
ISO/IEC 19762-5, Information technology — Automatic identification and data capture (AIDC) techniques —
Harmonized vocabulary — Part 5: Locating systems
ISO/IEC 24730-1, Information technology — Real-time locating systems (RTLS) — Part 1: Application
program interface (API)
Guidelines on Limiting Exposure to Non-Ionizing Radiation, International Commission on Non-Ionizing
Radiation Protection (ICNIRP), Munich, 1999
IEC 62369-1 ed1.0, Evaluation of human exposure to electromagnetic fields from short range devices (SRDs)
in various applications over the frequency range 0 GHz to 300 GHz — Part 1: Fields produced by devices
used for electronic article surveillance, radio frequency identification and similar systems
IEEE Std C95.1-2005, IEEE Standard for Safety Levels with Respect to Human Exposure to Radio Frequency
Electromagnetic Fields, 3 kHz to 300 GHz
© ISO/IEC 2010 – All rights reserved 1
---------------------- Page: 8 ----------------------
ISO/IEC 24730-5:2010(E)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 19762-1, ISO/IEC 19762-3,
ISO/IEC 19762-4, ISO/IEC 19762-5 and the following apply.
3.1
chirp spread spectrum
technique for spreading the bandwidth of a digital signal using linear frequency sweep signals
3.2
Class I
system that operates at a radiated power of up to 10 mW EIRP
3.3
Class II
system that operates at a radiated power higher than 10 mW up to the maximum defined by local regulations
3.4
ranging
process of determining the distance between two RTLS transceivers through the exchange of a specific set of
messages
3.5
ranging peer
RTLS transceiver with which to perform ranging
3.6
RF channel
combination of a centre frequency value and bandwidth value
3.7
RTLS tag
RTLS transceiver that accepts commands from RTLS readers and sends blinks and/or reports to the RTLS
readers
3.8
RTLS transmitter
part of an RTLS transceiver which is capable of sending messages
3.9
demultiplexer
equipment for reversing the process of multiplexing
3.10
medium
wireless channel
3.11
trilateration
method of determining the relative positions of objects using the known locations of three reference points and
the measured distance between the object to be located and each reference point
3.12
interleaving
rearrangement or transposition of data to enhance the effectiveness of error control schemes
3.13
interleaver
unit that performs interleaving (3.12)
2 © ISO/IEC 2010 – All rights reserved
---------------------- Page: 9 ----------------------
ISO/IEC 24730-5:2010(E)
3.14
baseband
frequency band occupied by the aggregate of the signals used to modulate a carrier before they combine with
the carrier in the modulation process
3.15
orthogonal
inner product being close to zero
3.16
peer X
x'th peer in a description of a situation with multiple peers
4 Symbols and abbreviated terms
ACK acknowledge
ARQ Automatic Repeat Query
BTS Backoff Time Slot
CIFS Carrier sense Inter Frame Space
CTS Clear To Send
CRC Cyclic Redundancy Check
CSMA/CA Carrier Sense Multiple Access / Collision Avoidance
CSS Chirp Spread Spectrum
dBr decibel relative
DEMUX demultiplexer
DQPSK Differential Quadrature Phase Shift Keying
DQPSK-CSS Differential Quadrature Phase Shift Keying over Chirp Spread Spectrum
Dst Destination address
EIRP Equivalent Isotropical Radiated Power
LFSR Linear Feedback Shift Register
LSB Least Significant Bit
MMSE Minimum Mean Square Error
MAC Medium Access Control
NAV Network Allocation Vector
PHR PHY header
PHY physical layer
PPDU PHY Protocol Data Unit
© ISO/IEC 2010 – All rights reserved 3
---------------------- Page: 10 ----------------------
ISO/IEC 24730-5:2010(E)
PSDU PHY Service Data Unit
QPSK Quadrature Phase Shift Keying
RTS Request To Send
RTLS Real Time Locating System
SFD Start of Frame Delimiter
SHR synchronization header
SIFS Short Inter Frame Space
Src source address
TWR Two Way Ranging
SDS-TWR Symmetric Double Sided Two Way Ranging
e Euler constant
j imaginary unit
M
~
0
s (t) continuous time baseband representation of 2-ary orthogonal CSS signal
M M
~ ~
0 0
r (t) implemented version of s (t)
M
~
1
s (t) continuous time baseband representation of DQPSK-CSS signal
m
M M
~ ~
1 1
r (t) implemented version of s (t)
m m
m configuration constant determining the type (one our of four possibilities) of sub-chirp
sequence used
M superscript indicating that 2-ary orthogonal CSS is described
0
M superscript indicating that DQPSK-CSS is described
1
k index variable
n index variable
b n'th symbol to be transmitted
n
c (t) continuous time baseband representation of chirp pulse b for 2-ary orthogonal CSS
b
µ configuration constant determining the chirp rate for 2-ary orthogonal CSS
0
µ constant determining the chirp rate for DQPSK-CSS
1
T timebase
base
4 © ISO/IEC 2010 – All rights reserved
---------------------- Page: 11 ----------------------
ISO/IEC 24730-5:2010(E)
T time in between two sub blinks
SBIFS
T average blink repetition time
Blink
T random time
Rand
T duration of time interval for during which the receiver of a tag is activated
Rxon
T maximum expected duration between a tag receiving any packets from infrastructure if such
Contact
is present
T duration of time interval during which a tag application shall respond to certain requests
TimeoutApplication
T duration of time for which a tag shall go to Wait state after leaving Range state
WaitAfterRange
T configuration constant determining the duration of a chirp pulse for 2-ary orthogonal CSS
0
T duration of sub-chirp sequence
1
T duration of sub-chirp
sub
T time position of k'th sub-chirp of n'th sub-chirp sequence of type m
n,k ,m
W (t) raised cosine window of duration T
T
α roll of factor of the raised cosine window
A amplitude variable which is minimized in minimum mean square error computation
τ time delay variable that is minimized in minimum mean square error computation
d
φ phase variable that is minimized in minimum mean square error computation
d information sample of k'th sub-chirp in n'th sub-chirp sequence
n,k
sub
C (t) continuous time baseband representation of k' sub-chirp of sub-chirp sequence type m
k,m
τ timing constant that determines the time-gap between subsequent sub-chirp sequences for
m
the sub-chirp sequence type m
f offset centre frequency of k'th sub-chirp in sub-chirp sequence type m
k,m
ζ chirp direction of k'th sub-chirp in sub-chirp sequence type m
k ,m
sub
S (t) continuous time baseband representation of sub-chirp sequence of type m
m
© ISO/IEC 2010 – All rights reserved 5
---------------------- Page: 12 ----------------------
ISO/IEC 24730-5:2010(E)
5 Overview
5.1 Components
The major components of a real-time locating system (RTLS) and the relationship of those components are
shown in Figure 1. As shown in this Figure the tags communicate with an infrastructure. The infrastructure
provides an application program interface (API)
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.