ETSI GR RIS 003 V1.2.1 (2025-02)

Reconfigurable Intelligent Surfaces (RIS); Communication Models, Channel Models, Channel Estimation and Evaluation Methodology

RGR/RIS-003

General Information

• Status: Not Published
• Technical Committee: RIS - Reconfigurable Intelligent Surfaces
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Due Date: 20-Feb-2025
• Completion Date: 07-Feb-2025

Standards Content (Sample)

GROUP REPORT
Reconfigurable Intelligent Surfaces (RIS);
Communication Models, Channel Models,
Channel Estimation and Evaluation Methodology
Disclaimer
The present document has been produced and approved by the Reconfigurable Intelligent Surfaces (RIS) ETSI Industry
Specification Group (ISG) and represents the views of those members who participated in this ISG.
It does not necessarily represent the views of the entire ETSI membership.

2 ETSI GR RIS 003 V1.2.1 (2025-02)

Reference
RGR/RIS-003
Keywords
methodology, RIS
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3 ETSI GR RIS 003 V1.2.1 (2025-02)
Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
1 Scope . 6
2 References . 6
2.1 Normative references . 6
2.2 Informative references . 6
3 Definition of terms, symbols and abbreviations . 7
3.1 Terms . 7
3.2 Symbols . 7
3.3 Abbreviations . 8
4 Introduction . 9
4.1 General Description . 9
4.2 Definition of RIS . 9
4.3 Types of RIS . 9
4.4 Deployment scenarios . 10
5 Models for RIS . 11
5.1 Models for communications . 11
5.1.1 General description . 11
5.1.2 Locally periodic discrete model . 11
5.1.3 Mutually-coupled antenna model . 11
5.1.4 Inhomogeneous sheets of surface impedance . 12
5.2 Models for radio localization and sensing . 13
5.2.1 Scenarios . 13
5.2.1.1 Localization scenarios . 13
5.2.1.2 SISO localization . 13
5.2.1.3 MISO localization . 13
5.2.1.4 SIMO localization . 14
5.2.1.5 MIMO localization . 14
5.2.1.6 RIS-aided and RIS-standalone . 14
5.2.2 Near-field . 15
5.2.2.1 Near-field regimes . 15
5.2.2.2 Near-field multiple paths . 16
5.2.2.3 Near-field single-path. 17
5.2.3 Far-field . 19
5.3 Continuous and discrete models . 20
6 Channel models . 20
6.1 Objectives of channel modeling and general principles . 20
6.2 Existing channel models . 21
6.3 Path-loss models . 21
6.3.1 Description of different cases . 21
6.3.1.1 General description . 21
6.3.1.2 General case . 22
6.3.1.3 Near-field case . 22
6.3.1.4 Far-field case . 23
6.4 Empirical channel model . 23
6.5 Multipath models . 24
6.5.1 Unstructured models for rich scattering (sub-6 GHz) environments . 24
6.5.2 Structured models for rich scattering (sub-6 GHz) environments . 25
6.5.3 Structured (geometric) models for high frequency bands . 25
6.6 Multi-mode reradiation models . 25
6.7 Interference and unwanted reradiation models . 26
6.7.1 Definition of interference and unwanted reradiation . 26
6.7.1.1 General description . 26
6.7.1.2 RIS contribution to the interference propagation channel (In-Band Reradiation) . 26
ETSI
4 ETSI GR RIS 003 V1.2.1 (2025-02)
6.7.1.3 Unwanted reradiations (Unexpected/Irregular/Discontinuously Time-Varying Out-Of-Band
Reradiation) . 28
6.7.2 Characterization of interference and unwanted reradiation . 28
6.7.2.0 General description . 28
6.7.2.1 Generated by the RIS itself . 29
6.7.2.2 Generated by other RIS . 29
6.7.2.3 Single and Multi/Inter-Operator Modeling . 29
6.7.2.4 Eavesdropping . 30
6.7.3 Destructive beamforming . 30
6.7.4 Modeling CSI mismatch due to interference and unwanted reradiation . 32
6.7.4.1 CSI mismatch due to interference (In-Band Reradiation) . 32
6.7.4.2 CSI mismatch due to Unwanted reradiations . 32
6.7.5 Spurious reradiation . 34
6.8 Polarized RIS element modeling . 35
7 Channel Estimation . 36
7.1 Reference scenarios .
...