ETSI TR 102 801 V1.1.1 (2015-03)

TECHNICAL REPORT
Electromagnetic compatibility
and Radio spectrum Matters (ERM);
Methods, parameters and test procedures for cognitive
interference mitigation techniques for use by PMSE devices
(Programme Making and Special Events)

2 ETSI TR 102 801 V1.1.1 (2015-03)

Reference
DTR/ERM-TG17WG3-013
Keywords
PMSE, radio
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3 ETSI TR 102 801 V1.1.1 (2015-03)
Contents
Intellectual Property Rights . 6
Foreword . 6
Modal verbs terminology . 6
Introduction . 6
1 Scope . 8
2 References . 8
2.1 Normative references . 8
2.2 Informative references . 8
3 Definitions and abbreviations . 9
3.1 Definitions . 9
3.2 Abbreviations . 9
4 Specialities of PMSE . 11
4.1 Overview . 11
4.2 Latency of service . 11
4.3 Availability of service . 11
4.4 Mobility . 11
4.5 SNR operational conditions . 12
4.6 Intermodulation . 12
5 Terminology on spectrum use . 12
5.1 Overview . 12
5.2 Definitions . 12
5.2.1 Spectral efficiency of a point to point connection . 12
5.2.2 Spectral efficiency of a wireless communication system . 12
5.2.3 Efficiency of spectrum use, sometimes also called short "spectral efficiency" . 13
5.3 Objective in the context of a C-PMSE system . 13
5.4 Spectral efficiency of a PMSE link . 13
6 Cognitive properties . 13
6.1 Overview . 13
6.2 General description of cognitive functionality . 13
6.3 Definition of Cognitive PMSE . 14
7 Functionality of a Cognitive PMSE System . 14
7.1 Overview . 14
7.2 General Concept of Cognitive PMSE . 14
7.3 Features of BMWi C-PMSE demonstrator . 15
7.3.1 General . 15
7.3.2 Ask before talk . 15
7.3.3 Spectrum sensing (listen before talk) and spectrum rating . 15
7.3.4 Reaction . 15
8 The Demonstrator in the BMWi C-PMSE Project . 16
8.1 Overview . 16
8.2 BMWi C-PMSE Project Overview . 16
8.3 Architecture of BMWi C-PMSE Demonstrator . 16
8.3.1 General . 16
8.3.2 Functional Blocks of BMWi C-PMSE Demonstrator . 17
8.3.3 Interfaces of realized demonstrator . 19
8.3.4 Limits of realized demonstrator . 19
9 Generalized C-PMSE system architecture . 20
9.1 Elements of the architecture . 20
9.1.1 General . 20
9.1.2 Functionality of SCS . 21
9.1.3 Functionality of LSDB. 21
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4 ETSI TR 102 801 V1.1.1 (2015-03)
9.1.4 Functionality of C-PMSE . 22
9.2 Interfaces . 22
9.2.1 Scanning Interface (sci) . 22
9.2.1.1 Overview . 22
9.2.1.2 Commands on sci interface . 22
9.2.2 Local Spectrum Database Interface (lsi) . 25
9.2.2.1 Overview . 25
9.2.2.2 Commands on lsi interface . 25
9.2.3 Radio link management interface (rli) . 26
9.2.3.1 Overview . 26
9.2.3.2 Device Management Process . 28
9.2.3.3 Dynamic Link Management Process . 28
9.2.3.4 Commands on rli interface . 28
10 Recommended test procedures for individual elements of SCS, LSDB and C-PMSE . 29
10.1 Technical requirement specification . 29
10.1.1 Scanning system (SCS) . 29
10.1.2 Scanning antenna (SCA) . 29
10.1.2.1 Definition . 29
10.1.2.2 Requirements . 29
10.1.2.3 Conformance . 30
10.1.3 Scanning receiver (SCR) . 30
10.1.3.1 Definition . 30
10.1.3.2 Requirements . 30
10.1.3.3 Conformance . 30
10.1.4 Scanning controller (SCC) . 30
10.1.4.1 Definition . 30
10.1.4.2 Requirements . 30
10.1.4.3 Conformance . 30
10.2 Local Spectrum Database (LSDB) . 30
10.2.1 Definition . 30
10.2.2 Requirements . 31
10.2.3 Conformance. 31
10.3 C-PMSE . 31
10.3.1 Definition . 31
10.3.2 Requirements . 31
10.3.3 Conformance. 31
10.4 Cognitive Engine (CEN) . 31
10.4.1 Definition . 31
10.4.2 Requirements . 31
10.4.3 Conformance. 32
11 Testing for compliance with technical requirements . 32
11.1 Test suites applied to SCS . 32
11.2 Test suites applied to LSDB . 32
11.3 Test suites applied to C-PMSE . 32
11.3.1 LSDB related tests . 32
11.3.2 C-PMSE dynamic reaction tests . 32
12 Example: Demonstration cases of the BMWi C-PMSE platform . 33
12.1 Scope . 33
12.2 Description of demonstration cases . 33
12.3 Automatic Setup Mode . 33
12.4 Operational mode (automatic / interactive) . 34
12.4.1 General . 34
12.4.2 Frequency agile behaviour . 34
12.4.3 Transmit power agile behaviour . 34
13 Heterogeneous C-PMSE. 35
13.1 General description of heterogeneous C-PMSE system operation . 35
13.2 Scenarios with heterogeneous C-PMSE . 35
13.2.1 General . 35
13.2.2 Scenario 1 . 35
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5 ETSI TR 102 801 V1.1.1 (2015-03)
13.2.3 Scenario 2 . 36
13.2.4 Scenario 3 . 36
13.2.5 Scenario 4 . 37
13.2.6 Scenario 5 . 37
13.2.7 Scenario 6 . 38
13.3 Interconnection with legacy PMSE systems. 39
13.4 Capability of location awareness (e.g. GNSS) . 39
13.5 Coexistence of various types of PMSE systems e.g. video cameras, IEM (in ear monitor) . 39
13.6 Extension to power control, adaptive modulation and coding (AMC) . 39
14 Recommendation to reuse PAWS protocol for Communication to GLDB . 39
14.1 GLDB access within BMWi C-PMSE project . 39
14.2 Automatic request for spectrum grant . 40
14.3 Spectrum sharing with WSD . 40
14.4 Suggestions for a standardized interface gli between LSDB and GLDB . 40
14.4.1 General . 40
14.4.2 PAWS command "Database Discovery" . 40
14.4.3 PAWS command "Device Initialization" . 40
14.4.4 PAWS command "Device Registration" . 41
14.4.5 PAWS command "Available Spectrum Query" . 41
14.4.6 PAWS command "Device Validation" . 42
14.5 Status of PAWS protocol . 42
15 Consequences for ETSI EN 300 422-1 . 42
15.1 Scope . 42
15.2 Wireless signalling . 42
15.3 Architecture . 43
15.4 Interfaces . 43
15.5 Necessary additions to ETSI EN 300 422-1 (TDOC220). 43
15.5.1 Introduction. 43
15.5.2 Implementation . 43
15.5.3 Proposal for additions to existing standard . 44
15.5.4 Proposal for addition of a new Part III . 44
16 Conclusions . 44
16.1 Summary . 44
16.2 Suggestions for standardization . 45
16.3 Implications to spectrum regulators . 45
Annex A: Bibliography . 46
History . 49

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6 ETSI TR 102 801 V1.1.1 (2015-03)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://ipr.etsi.org).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This Technical Report (TR) has been produced by ETSI Technical Committee Electromagnetic compatibility and Radio
spectrum Matters (ERM).
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
Introduction
The present document is the deliverable of phase 3 work by ETSI STF 386. It is a refinement of the concepts and
methods depicted in earlier documents by phase 1 and phase 2. Phase 1 has generated document ETSI TR 102 799 [i.2]
and phase 2 document ETSI TS 102 800 [i.6].
The refinement is based on the experience and lessons learnt during the course of a German national research project
called "C-PMSE" funded by the German Federal Ministry of Economics and Technology (BMWi). This project had the
aim of ensuring the high quality of productions with PMSE under a dynamically changing interference situation.
The present document therefore reflects several modifications to the originally proposed architecture of a cognitive
interference mitigation system and spectrum access for PMSE and to the methods of operating it.
As the majority of partners and experts participating in STF 386 were also partners on the German Research project, a
smooth transfer of public information gained in the research project to the STF 386 work was ensured.
The present document will highlight the changes made to the architectural concepts and operation methods for cognitive
interference mitigation with PMSE over the phase 1 and phase 2 deliverables as a consequence of the findings by the
German research project.
The present document provides recommendations on the interfaces that need to be standardized to ensure proper
functionality of interference mitigation techniques.
As the german research project ran a large demonstration tested at Messe Berlin, several tests of cognitive behaviour
have been conducted there and a deep understanding of necessary tests has been developed which serves as the basis for
defining recommended test cases in the present document. The aim is to recommend test cases that should be
incorporated in the relevant standards.
C-PMSE technology and measurement procedures should be incorporated in ETSI EN 300 422-1 [i.1] and
ETSI EN 301 489-1 [i.4] and ETSI EN 301 489-9 [i.7] as soon as practicable in order to encourage the development and
widespread use of cognitive PMSE systems in the market.
Although the testings and demonstrations with the German research project have focussed on UHF TV Band, the
findings on refinement of architecture and operation method are applicable to other bands.
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7 ETSI TR 102 801 V1.1.1 (2015-03)
During Phases 1 and 2, the STF 386 has accomplished the following work:
• Investigated methods, principles and techniques for spectrum access systems for PMSE technologies and for
the guarantee of a high sound production quality on selected frequencies utilizing cognitive interference
mitigation techniques.
• Delivered an ETSI Technical Report ETSI TR 102 799 [i.2] on "Operation methods and principles for
spectrum access systems for PMSE technologies and for the guarantee of a high sound production quality on
selected frequencies utilizing cognitive interference mitigation techniques".
• Delivered an ETSI Technical Specification on the recommended spectrum access technique, defined in
ETSI TS 102 800 [i.6] on "Electromagnetic compatibility and Radio spectrum Matters (ERM); Cognitive
Programme Making and Special Events (C-PMSE); Protocols for spectrum access and sound quality control
systems using cognitive interference mitigation techniques".
During Phase 3, the STF 386 performed the following work:
• Specified test procedures based on experience gained during the BMWi research project. Please note that
although the technology demonstrator at Messe Berlin concentrated on one particular PMSE application and
frequency band, the theory is applicable to all PMSE applications.
• Delivered the present document containing the defined compliance tests for the proposed spectrum access
mechanism evolved from ETSI TR 102 799 [i.2] and ETSI TS 102 800 [i.6]. STF 386 by the present document
proposes the type of compliance required, which will be different from the current ETSI EN 300 422-1 [i.1]
specifications.
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8 ETSI TR 102 801 V1.1.1 (2015-03)
1 Scope
The present document proposes an architecture for C-PMSE. This includes e.g. procedures, protocol, elements and
interfaces.
The goal is to ensure high production quality with PMSE while raising efficiency of spectrum use.
2 References
2.1 Normative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are necessary for the application of the present document.
Not applicable.
2.2 Informative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] ETSI EN 300 422-1 (V1.4.2): "Electromagnetic compatibility and Radio spectrum Matters (ERM);
Wireless microphones in the 25 MHz to 3 GHz frequency range; Part 1: Technical characteristics
and methods of measurement".
[i.2] ETSI TR 102 799: "Electromagnetic compatibility and Radio spectrum Matters (ERM); Operation
methods and principles for spectrum access systems for PMSE technologies and the guarantee of a
high sound production quality on selected frequencies utilising cognitive interference mitigation
techniques".
[i.3] Recommendation ITU-R SM.2152, (09/2009): "Definitions of Software Defined Radio (SDR) and
Cognitive Radio System (CRS)".
[i.4] ETSI EN 301 489-1: "Electromagnetic compatibility and Radio spectrum Matters (ERM);
ElectroMagnetic Compatibility (EMC) standard for radio equipment and services;
Part 1: Common technical requirements".
[i.5] Recommendation ITU-R BT.2069-5 (05/2011): "Tuning ranges and operational characteristics of
terrestrial electronic news gathering (ENG), television outside broadcast (TVOB) and electronic
field production (EFP) systems".
[i.6] ETSI TS 102 800: "Electromagnetic compatibility and Radio spectrum Matters (ERM); Cognitive
Programme Making and Special Events (C-PMSE); Protocols for spectrum access and sound
quality control systems using cognitive interference mitigation techniques".
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9 ETSI TR 102 801 V1.1.1 (2015-03)
[i.7] ETSI EN 301 489-9: "Electromagnetic compatibility and Radio spectrum Matters (ERM);
ElectroMagnetic Compatibility (EMC) standard for radio equipment and services; Part 9: Specific
conditions for wireless microphones, similar Radio Frequency (RF) audio link equipment, cordless
audio and in-ear monitoring devices".
[i.8] ECC Report 002: "SAP/SAB (Incl. ENG/OB) spectrum use and future requirements".
[i.9] 2013-12-02-IETF-PAWS Protocol to Access White-Space Databases (Internet-draft).
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
audio base station: audio PMSE equipment that is fixed and part of C-PMSE Device
audio terminal: audio PMSE equipment that is moving
C-PMSE system: constituted out of information acquisition and C-PMSE
CENbase: radio resource management including all time critical processes of CEN
content plane: contains audio and/or video information, analogue or digital
control plane: plane which contains only control information (signalling), e.g. Radio Resource commands, battery
status, etc.
NOTE: The term data plane/data channel is not used in the present document due to potential irritations. Instead
control and content plane are used.
ePMSE: evolved PMSE, a combination of content and control plane whose radio parameters of content plane can be
altered electronically simultaneously on both ends of radio link
information acquisition: acquires information about actual spectrum use and assignments
PMSE link: describes the content-plane only
shared infrastructure: C-PMSE information acquisition can be shared among multiple C-PMSE, regardless of mobile,
nomadic or fixed use
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
AMC Adaptive Modulation and Coding
AMCT Adaptive Modulation and Coding Table
ASQ Action Sequencer
BER Bit Error Rate
BMWi German Ministry of Research and Education
CDMA Code Division Multiple Access
CEN Cognitive Engine
CENbase Time critical processes of CEN
CPC Cognitive Pilot Channel
cpi Interface between co-located Radio Resource Managers
C-PMSE IA C-PMSE Information Acquisition
C-PMSE Cognitive PMSE
CR Cognitive Radio
CRS Cognitive Radio System
DAT Device Allocation Table
DBC Internal Database of CEN
DBS Database
DMO Demonstration Monitor
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10 ETSI TR 102 801 V1.1.1 (2015-03)
DUT Device Under Test
DVB-T Digital Video Broadcasting - Terrestrial
ECC Electronic Communication Committee
ePMSE Evolved PMSE
EVM Error Vector Magnitude
FAT Frequency Allocation Table
fci Interface between CEN and LSPM
FCO Frequency Coordinator
FM Frequency Modulation
GLDB Geolocation Database
gli Interface between Local Spectrum Database and Gelocation Database
GNSS Global Navigation Satellite System
GSM Global System for Mobile Communication
GUI Graphical User Interface
HAL Hardware Abstraction Layer
HW Hardware
IA Information Acquisition, combines Scanning System and Frequency Booking
IEM In Ear Monitor
IETF Internet Engineering Task Force
IM Intermodulation
IRT Institut für Rundfunktechnik GmbH
ITU-R International Telecommunication Union - Radio
LAT Link Allocation Table
LQI Link Quality Indicator
LSDB Local Spectrum Database
lsi Interface between Local Spectrum Database and CEN
LSPM Local Spectrum Portfolio Manager
LTE Long Term Evolution
MIMO Multiple In Multiple Out
NRA National Regulatory Authority
OTA Over the Air
P2MP Point to Multipoint
P2P Point to Point
PAT Power Allocation Table
PAWS Protocol to Access White Space Database
PLL Phase Lock Loop
PMO Performance Monitor
PMSE Program Making and Special Events
PSME Program Making and Special Events
PWMS Professional Wireless Microphone System
QAM Quadrature Amplitude Modulation
QPSK Quadrature Phase Shift Keying
REM Radio Environment Map
RF Radio Frequency
rli Interface between Hardware Abstraction Layer and CEN
RRM Radio Resource Manager
RSSI Radio Signal Strength Indicator
SCA Scanning Antenna
SCC Scanning Controller
sci Interface between Scanning System and CEN
SCR Scanning Receiver
SCS Scanning System
SINR Signal to interference plus noise ratio
SLE Service Level Entry
SNR Signal to noise ratio
STF Special Task Force
TCP/IP Transmission Control Protocol / Internet Protocol
TV Television
UHF Ultra High Frequency
WSD White Space Device
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11 ETSI TR 102 801 V1.1.1 (2015-03)
4 Specialities of PMSE
4.1 Overview
PMSE especially PWMS have specific requirements that differ from other wireless systems. In the following some
aspects are discussed.
4.2 Latency of service
PMSE has to serve very stringent latency requirements. The difference to most other wireless systems is that with
PMSE the information source is co-located with the information sink, e.g. an artist is using a wireless microphone and
simultaneously an In Ear Monitor.

Figure 1: Roundtrip Problem scenario
The loopback from the artist back to the artist is enriched by the mixing console, where the information from other
artists are added.
Experience from drummer artists tells that a roundtrip of smaller than 5 ms is needed for a high quality artistic
performance. Assuming 1 ms for the mixing console, one PMSE link would be allowed to have maximum 3 ms latency.
If with an event multiple microphones are used there is also a further requirement on the latency differences between
the links as this may lead to acoustic holes (comb filtering) in spatial sound production or loss of synchronization
between audio and video production.
4.3 Availability of service
PMSE applications have high requirements in terms of availability of service. Availability should be 100 %. In a high
quality production loss of a wireless link, leading to interruptions of the audio link, called drop-outs, are not acceptable.
In general no perceived interruption whatever root cause can be tolerated. As variations of received signal strength due
to fading may easily reach 30 dB, typically a high margin and diversity gains are implemented on the link budget.
An event or performance cannot be repeated. Mostly these are unique events, so information would be lost totally. In
other communication systems lost data can be repeated, which of course adds latency.
Robustness of transmission cannot be gained by wide temporal interleaving as this would introduce unacceptably large
latency.
4.4 Mobility
Some artistic performances and ENG applications involve high speed by mobile terminals, like wireless microphones
with singers on skates e.g. with Musicals Cats and Holiday on Ice or reports from cars. Therefore typically speeds up to
80 km/h have to be supported, i.e. PMSE need to support mobility.
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12 ETSI TR 102 801 V1.1.1 (2015-03)
4.5 SNR operational conditions
RF SINR operational conditions for analogue FM links are higher than for other systems. As the 20 kHz audio
bandwidth is typically expanded to 200 kHz wide RF channels, there is only a 10 dB bandwidth expansion gain by FM.
This means that audio SNR is only 10 dB better than the RF SNR. So if an non-companded audio SNR of 60 dB is
demanded, the SINR at RF has to be 50 dB. For reference GSM could work successfully with 7 dB to 9 dB SINR and
CDMA systems may also work with negative SINR.
4.6 Intermodulation
In PMSE deployments one may face not only strong receiver, but also strong transmitter intermodulation. If for
example an artist carries a wireless microphone and an instrument transmitter or if two singers stand close with their
wireless microphones, reverse intermodulation can happen, meaning that part of the transmitter power from one
wireless microphone enters the output stages of the other wireless microphone. Intermodulation's products will be
generated due to non-linear behaviour of the output stage. As the operational RF SINR values are typically much higher
than in other systems, PMSE is more vulnerable to transmitter and receiver intermodulation. This is the reason why
intermodulation products are carefully planned up to IM5 products.
5 Terminology on spectrum use
5.1 Overview
For performing an optimization in terms of spectrum use, it is important to have a clear understanding of the metrics to
be improved. In the following various metrics are presented. As there is also a lot of confusion in the definition of the
term "spectral efficiency" the terminology is revisited here.
5.2 Definitions
5.2.1 Spectral efficiency of a point to point connection
The term "spectral efficiency of a P2P connection" describes the properties of a transmission scheme for a point-to-
point link. It reflects the number of bits transported per second within a given bandwidth. It is measured bit/s/Hz. It can
be increased by several options:
a) Increasing the order of modulation, e.g. from QPSK to 256 QAM.
b) Applying Source coding. With digital transmission e.g. MP3 could be used to reduce the amount of data to be
transmitted. With analogue transmission an analogue compander reduces the dynamic range and which is a
way of increasing spectral efficiency. Source coding is not only applicable to digital transmission, it is
applicable to analogue transmission as well.
c) MIMO. This means multiple antennas at the transmitter and multiple antennas at the receiver. If the
propagation channel offers a lot of reflections, the spectral efficiency more or less scales linearly with the
number of antennas.
5.2.2 Spectral efficiency of a wireless communication system
The term "Spectral efficiency of a wireless communication system" describes the number of bits transported within a
second and within a given bandwidth summed over all users normalized to served area. It is measured bit/s/Hz/km . It
therefore reflects an aggregation over all users, thus multiple links, versus above definition which reflects only one link.
This spectral
...