IEC TR 62669:2011

Case studies supporting IEC 62232 - Determination of RF field strength and SAR in the vicinity of radiocommunication base stations for the purpose of evaluating human exposure

IEC/TR 62699:2011(E) is a technical report. It contains a series of case studies for the evaluation of electromagnetic (EM) sources in the frequency range 100 kHz - 300 GHz to support the methods detailed in the international standard IEC 62232, Determination of RF field strength and SAR in the vicinity of radiocommunication base stations for the purpose of evaluating human exposure. Using the methods detailed in the standard, each case study has been chosen to illustrate a typical radio base station (RBS) evaluation scenario. Some of the case studies demonstrate more than one evaluation method. However, in most situations only one method would be required to complete an evaluation. The case studies documented in this report are provided for guidance only and are not a substitute for a thorough understanding of the requirements of IEC 62232. This publication contains attached files in the form of a CD-ROM for the paper version and embedded files for the electronic version. These files are intended to be used as a complement and do not form an integral part of the standard.

General Information

• Status: Published
• Publication Date: 26-May-2011
• ICS: 13.280 - Radiation protection
• ICS: 17.240 - Radiation measurements
• Technical Committee: TC 106 - Methods for the assessment of electric, magnetic and electromagnetic fields associated with human exposure
• Current Stage: DELPUB - Deleted Publication
• Start Date: 05-Apr-2019
• Completion Date: 30-Apr-2018

Relations

• Revised: IEC TR 62669:2019 - Case studies supporting IEC 62232 - Determination of RF field strength, power density and SAR in the vicinity of radiocommunication base stations for the purpose of evaluating human exposure
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC/TR 62669 ®
Edition 1.0 2011-05
TECHNICAL
REPORT
colour
inside
Case studies supporting IEC 62232 – Determination of RF field strength and SAR
in the vicinity of radiocommunication base stations for the purpose of evaluating
human exposure
IEC/TR 62669:2011(E)
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IEC/TR 62669 ®
Edition 1.0 2011-05
TECHNICAL
REPORT
colour
inside
Case studies supporting IEC 62232 – Determination of RF field strength and SAR
in the vicinity of radiocommunication base stations for the purpose of evaluating
human exposure
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XH
ICS 13.280; 17.240 ISBN 978-2-88912-528-9
– 2 – TR 62669 © IEC:2011(E)
CONTENTS
FOREWORD . 3

INTRODUCTION . 5

1 Scope . 6

2 Normative references . 6

3 Terms, definitions, symbols and abbreviated terms . 6

4 Overview of case studies . 6

4.1 Case study synopsis . 6

4.2 Micro cell case study . 7
4.3 Roof-top case study with nearby apartment buildings . 8
4.4 Roof-top / tower case study in residential area . 9
4.5 Roof-top case study with direct access to antennas . 10
4.6 Roof-top case study with large antennas and no direct access . 11
4.7 Circular cylindrical compliance boundary determination case study with large
antennas and no direct access . 11
4.8 Tower case study in parkland . 12
4.9 Multiple towers case study at sports venue . 13
4.10 In-building base station case study . 14
Annex A (informative) Micro cell case study . 16
Annex B (informative) Roof-top case study with nearby apartments . 41
Annex C (informative) Roof-top / tower case study in residential area . 68
Annex D (informative) Roof-top case study with direct access to antennas . 98
Annex E (informative) Roof-top case study with no direct access to antennas . 126
Annex F (informative) Circular cylindrical compliance boundary determination case
study . 143
Annex G (informative) Tower case study in parkland . 155
Annex H (informative) Tower case study at sports venue . 170
Annex I (informative) In-building base station case study . 191
Annex J (informative) Evaluation template and sample uncertainty table . 212

Figure 1 – Micro cell case study . 7
Figure 2 – Roof-top case study with nearby apartment buildings . 8

Figure 3 – Roof-top / tower case study in residential area . 9
Figure 4 – Roof-top case study with direct access to antennas . 10
Figure 5 – Roof-top case study with large antennas and no direct access . 11
Figure 6 – Cylindrical compliance boundary determination for dual band antenna on
building . 12
Figure 7 – Tower case study in parkland . 13
Figure 8 – Multiple towers case study at sports venue . 14
Figure 9 – Office building IBC case study . 15

TR 62669 © IEC:2011(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
CASE STUDIES SUPPORTING IEC 62232 –

DETERMINATION OF RF FIELD STRENGTH AND SAR IN THE VICINITY

OF RADIOCOMMUNICATION BASE STATIONS FOR THE PURPOSE

OF EVALUATING HUMAN EXPOSURE
FOREWORD
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC 62669, which is a technical report, has been prepared by IEC technical committee 106:
Methods for the assessment of electric, magnetic and electromagnetic fields associated with
human exposure.
This publication contains attached files in the form of a CD-ROM for the paper version and
embedded files for the electronic version. These files are intended to be used as a
complement and do not form an integral part of the technical report.

– 4 – TR 62669 © IEC:2011(E)
The text of this technical report is based on the following documents:

Enquiry draft Report on voting

106/199/DTR 106/208/RVC
Full information on the voting for the approval of this technical report can be found in the

report on voting indicated in the above table.

This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

The committee has decided that the contents of this publication will remain unchanged until
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related to the specific publication. At this date, the publication will be
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IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
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colour printer.
TR 62669 © IEC:2011(E) – 5 –
INTRODUCTION
This technical report contains a series of case studies for the evaluation of electromagnetic

(EM) sources in the frequency range 100 kHz - 300 GHz to support the methods detailed in

the international standard IEC 62232, Determination of RF field strength and SAR in the

vicinity of radiocommunication base stations for the purpose of evaluating human exposure.

Using the methods detailed in the standard, each case study has been chosen to illustrate a

typical radio base station (RBS) evaluation scenario.

– 6 – TR 62669 © IEC:2011(E)
CASE STUDIES SUPPORTING IEC 62232 –

DETERMINATION OF RF FIELD STRENGTH AND SAR IN THE VICINITY

OF RADIOCOMMUNICATION BASE STATIONS FOR THE PURPOSE

OF EVALUATING HUMAN EXPOSURE
1 Scope
This technical report presents a series of case studies in which electromagnetic (EM) fields
are evaluated in accordance with IEC 62232. It also provides a reporting template cross
referenced to IEC 62232.
Each case study has been chosen to illustrate a typical radio base station (RBS) evaluation
scenario and employs the methods detailed in IEC 62232. Some of the case studies
demonstrate more than one evaluation method. However, in most situations only one method
would be required to complete an evaluation.
The case studies documented in this report are provided for guidance only and are not a
substitute for a thorough understanding of the requirements of IEC 62232.
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.
IEC 62232: Determination of RF field strength and SAR in the vicinity of radiocommunication
base stations for the purpose of evaluating human exposure
3 Terms, definitions, symbols and abbreviated terms
For the purposes of this document, the terms, definitions, symbols and abbreviated terms
given in IEC 62232 apply.
4 Overview of case studies
4.1 Case study synopsis
This clause provides a summary of worked evaluation examples at a number of RBS sites
using a range of methods described in IEC 62232. The example sites include roof-tops,
towers, poles, micro cells and in-building cells.
The case studies have been chosen to illustrate typical RBS sites and common evaluations.
Some of the case studies demonstrate multiple evaluation methods. However in most
situations only one method would be required to complete an evaluation.
NOTE The coloured left-side page margins in the annexes indicates the pages are unchanged versions of sample
RF exposure evaluation reports contributed by TC 106 project team members.

TR 62669 © IEC:2011(E) – 7 –
4.2 Micro cell case study
The purpose of this case study was to evaluate the RF exposure compliance boundaries from

a particular micro cell installation on a building wall to determine whether they would extend

to a nearby awning. Compliance boundaries were determined based on a) basic restrictions

and b) reference levels to determine the minimum distance from the antenna to the

compliance boundary.
The maximum values were compared against international safety guidelines known as ICNIRP

(International Commission on Non-Ionizing Radiation Protection) guidelines. The assessment

establishes compliance against the basic restrictions known as specific absorption rate (SAR)

and the spatially averaged field strength reference levels. SAR testing was performed in a
laboratory and frequency selective field measurements were performed on site.
The equipment under test (EUT) was categorised as a simple RBS due to the single
technology and single antenna of the micro cell. Nearby base stations, known as secondary
sources, had negligible impact on both SAR and field strength evaluations.
The measured SAR and field strength levels were extrapolated to assess the maximum power
configuration for the site.
The “best estimate” uncertainty model was applied and the measured levels are reported
including the extrapolation for maximum base station power configuration. The uncertainty is
stated for all assessment methods used.
The compliance boundary distance for general public exposure using the on-site field strength
measurement was 0,8 m and 0,08 m using the SAR evaluation.
Both the SAR evaluation and the on-site field strength measurements confirm that the general
public exposure compliance boundary from the micro cell antenna does not extend onto the
building awning, therefore access is permitted on the awning.
This case study illustrates:
• the benefit of conducting a SAR evaluation on the small micro cell antenna to minimise its
exclusion zone;
• evaluation of RF fields from cellular base station antennas located in close proximity to a
roof-top awning accessible to maintenance staff.
Figure 1 shows the surveyor and the micro cell antenna installed on the building wall in
Stockholm. The case study is available in full in Annex A.

Figure 1 – Micro cell case study

– 8 – TR 62669 © IEC:2011(E)
4.3 Roof-top case study with nearby apartment buildings

The purpose of this case study was to verify the RF exposure levels in the accessible areas of

an office building roof-top with a cellular base station are below the uncontrolled environment

exposure limits in Health Canada’s Safety Code 6 Guidelines. The building roof-top has

cellular base station panel antennas from two separate operators, and is located near an
apartment building, residential and commercial areas.

The equipment under test (EUT) was categorised as a Complex RBS as there are multiple

antenna systems at the site under evaluation.

This evaluation was performed by Industry Canada as part of their regulatory auditing

program of radio communication and broadcasting sites. The evaluation consisted of
computational modelling to determine the RF exposure compliance boundaries around the
antennas, and on-site frequency selective field strength measurements to determine the RF
exposure levels in accessible areas.
The RF exposure compliance boundary (uncontrolled environment) was assessed to be 6 m
directly in front of the panel antennas.
The maximum exposure level on the building roof-top was assessed to be 5,1% of Safety
Code 6 limits for the uncontrolled environment. This was on the southwest side of the roof-top
underneath the cellular base station panel antennas. The maximum exposure level on the
building adjacent to the base station was assessed to be 0,51% of Safety Code 6 limits for the
uncontrolled environment. This was on the roof-top car park.
Results are presented for this case study using both the best estimate and upper 95 % CI
assessment schemes. The exposure levels reported using the upper 95 % CI assessment
scheme i.e. including the measurement equipment expanded uncertainty in the reported level.
The exposure levels reported using the best estimate assessment scheme state the actual
level evaluated and the uncertainty factor for the measurement equipment.
This case study illustrates:
• evaluation of RF field strength from cellular base station antennas which are mounted on
the roof-top of an office building and are accessible to maintenance workers;
• evaluation of RF field strength from cellular base stations which are located near an
apartment building, residential and commercial areas;
• full compliance assessment of the site is achieved even if accessibility to certain locations
was not possible;
• the results of two spatial averaging schemes are compared.
Figure 2 (left) shows the roof-top installation from a position across the street; while Figure 2

(right) shows the surveyor and base station antennas in-situ. The building is located in
Montreal. The case study is available in full in Annex B.

Figure 2 – Roof-top case study with nearby apartment buildings

TR 62669 © IEC:2011(E) – 9 –
4.4 Roof-top / tower case study in residential area

The purpose of this case study was to verify RF exposure compliance in a residential and

commercial area surrounding a building with a roof-top cellular base station and satellite

broadcast radio repeater. The antenna structure is mounted on the second level roof-top of an

office building. The equipment under test (EUT) was categorised as a Complex RBS as there
are multiple antenna systems at the site under evaluation.

This assessment compared the results of the evaluations against limits set forth in Health
Canada’s Safety Code 6 guidelines. This compliance assessment was performed by Industry

Canada as part of their regulatory auditing program of radio communication and broadcasting

sites. The evaluations consisted of computational modelling to determine the RF exposure

compliance boundaries around the antennas, and frequency selective field strength
measurements to determine the RF exposure levels in the surrounding residential and
commercial areas. The accessible areas of the roof-top were also measured.
The RF exposure compliance boundary (uncontrolled environment) was assessed to be 4 m
directly in front of the cellular panel antennas, and 2 m directly in front of the satellite
broadcast repeater antenna.
The maximum exposure level on the building roof-top was assessed to be 23,92 % of Safety
Code 6 limits for the uncontrolled environment which was located a few meters in front of the
satellite broadcasting repeater. This location is not accessible to the general public. The
maximum exposure level in the residential and commercial areas around the building was
assessed to be 0,044 % of Safety Code 6 limits for the uncontrolled environment.
Results are presented for this case study using both the best estimate and upper 95 % CI
assessment schemes. The exposure levels reported using the upper 95 % CI assessment
scheme include the measurement equipment expanded uncertainty in the reported level. The
exposure levels reported using the best estimate assessment scheme state the actual level
assessed and the uncertainty factor for the measurement equipment.
This case study illustrates:
• evaluation of RF field strength from cellular base station antennas and satellite broadcast
radio repeater which are mounted on a multi-storey building, which houses a centre for
continuing education;
• evaluation of RF field strength from cellular base station signals in a residential area;
• the comparison of the results of two (2) spatial averaging schemes.
Figure 3 shows the building in Montreal, which is subject of the evaluation; Figure 3 (left) is
wide shot of the environment surrounding the building, while a close-up of the structure and

antennas is shown in Figure 3 (right). The case study is available in full in Annex C.

Figure 3 – Roof-top / tower case study in residential area

– 10 – TR 62669 © IEC:2011(E)
4.5 Roof-top case study with direct access to antennas

The purpose of this case study was to determine the RF exposure compliance and control

boundaries around an operational roof-top macro base station. It demonstrates the validity of

both measurement and computation evaluation methods for this base station situation.

The compliance boundary assessment determined the area around the base station antennas
where the exposure limits are not exceeded, and the control boundary assessment confirmed

the location of the physical access controls such as barriers and warning signs. The

evaluation included on-site spatially averaged field strength measurement at the control

boundary and a desktop computation to determine the compliance boundary. The maximum

values were compared against the ICNIRP international safety guidelines.

An initial visual inspection at the site showed the potential for a significant RF field
contribution from other RF sources. A wide frequency sweep established that the ambient
contribution would not be significant and hence only the RF fields from the RBS under
evaluation needed to be considered. Prior to the on-site field strength measurements, an
initial estimate of the control boundary distance was calculated to be 13,2 m from the
antennas for the general public limit and 3,2 m for the occupational exposure limit.
Spatially averaged field strength measurements were then performed on the roof-top at the
selected control boundary distances of 13,2 m and 3,2 m from the antennas. The
measurements demonstrated the actual field strength levels were well below the occupational
and general public limits allowing for the maximum operating power. This verifies that
conservative control boundaries have been selected.
A separate desktop evaluation using a commercial computation tool with ray tracing
determined that the distance from the antenna to general public compliance boundary was
less than 10 m, and less than 1 m to the occupational compliance boundary, along the
maximum exposure radial under maximum operating power.
Full uncertainty analyses were performed for both evaluation methods indicating high
confidence that actual exposure would be less than the ICNIRP limits at the specified control
boundary distances. The best estimate assessment scheme was used for both the desktop
evaluation and field strength measurement.
This case study illustrates:
• evaluation of RF field strength from cellular base station antennas with direct access to
the antennas;
• comparison of computational evaluation and on-site measurement;
• identification of compliance boundaries on the roof-top.

Figure 4 shows the evaluation site, in Cape Town. It is an example of a roof-top site with
direct access to the antennas, which in this example are flush mounted on building’s exterior.
The case study is available in full in Annex D.

Figure 4 – Roof-top case study with direct access to antennas

TR 62669 © IEC:2011(E) – 11 –
4.6 Roof-top case study with large antennas and no direct access

The purpose of this case study is to evaluate the RF exposure levels in accessible areas on a

building roof-top in Tokyo.
The equipment under test (EUT) was categorised as a Complex RBS due to the multiple

frequency bands and technologies supported.

The evaluation involved frequency selective measurements of the radio base station control

channels and extrapolation for maximum operating power. The maximum values were

compared against the ICNIRP guideline.

The assessment showed that the total exposure level from the mobile base station antennas
in accessible areas of the building roof-top was lower than the specified limits at maximum
traffic, as well as at the available maximum transmitting power.
This evaluation was performed using a target uncertainty assessment scheme. If the target
uncertainty is met, then the measured value is compared directly with the limit. If the target
uncertainty is not met, then the comparator is the measured value increased to the upper
95 % confidence level. In this case study the target uncertainty was met.
This case study illustrates:
• RF exposure levels in accessible areas of a building roof-top from a complex base station;
• an assessment using a target uncertainty scheme;
• comparison of computational evaluation and on-site measurements;
• frequency selective spatial average measurements;
• evaluation of nearby radio and broadcast signal levels.
Figure 5 shows the roof-top in Isehara City, Japan used for this case study.
The case study is available in full in Annex E.

Figure 5 – Roof-top case study with large antennas and no direct access
4.7 Circular cylindrical compliance boundary determination case study with large
antennas and no direct access
The purpose of this survey was to determine a radio frequency (RF) exposure compliance
boundary (occupational and general public) for a specific combined Long Term Evolution
(LTE) and GSM site in Stockholm.
The compliance boundaries were evaluated against the international safety guidelines known
as the ICNIRP (International Commission on Non-Ionizing Radiation Protection) guidelines.
The assessment was made in terms of the Specific Absorption Rate (SAR) for adult RF
exposure using formulae for SAR estimation.

– 12 – TR 62669 © IEC:2011(E)
The compliance boundary for occupational exposure using the cylinder SAR model was

assessed to be 0,5 m in diameter and 1,4 m height in front of the antenna.

The compliance boundary for general public exposure using the cylinder SAR model was

assessed to be 1,7 m in diameter and 1,5m height in front of the antenna.

Results are presented for this case study using the upper 95 % CI assessment scheme. The

SAR exposure level is reported and the uncertainty value stated.

This case study illustrates:
• a compliance boundary assessment for a combined GSM and LTE base station;
• a compliance boundary assessment using a SAR model.

Figure 6 – Cylindrical compliance boundary determination
for dual band antenna on building

Figure 6 shows a radio base station antenna on a roof-top in Stockholm which was the subject
of this evaluation involving GSM and LTE systems.
The case study is available in full in Annex F.
4.8 Tower case study in parkland
This case study evaluates the RF exposure levels in a playing field in close proximity to a
radio tower with broadcast and cellular base station radio services.
The purpose of the survey was to determine observed field strength values along footpaths
and on a sports field adjacent to a base station site at a church green in Essex UK. The
maximum values would then be compared against international safety guidelines known as
ICNIRP (International Commission on Non-Ionizing Radiation Protection) guidelines.

TR 62669 © IEC:2011(E) – 13 –
The equipment under test (EUT) was categorised as a Complex RBS due to the multiple

frequency bands and technologies supported.

Unknown transmitters on site meant that the assessment was conducted by on-site

measurement. All values recorded were well below ICNIRP general public reference levels.

The maximum values recorded corresponded to 0,295 % of the ICNIRP reference level.

This evaluation was conducted using the best estimate assessment scheme where the

measured levels are reported and uncertainty stated.

This case study illustrates:
• RF exposure levels on a playing field in close proximity to a radio tower;
• an RF exposure assessment where site configuration details for some of the radio
services are unknown.
Figure 7 – Tower case study in parkland
The location for the evaluation site was Essex, in the United Kingdom. The structure and
antennas are shown in Figure 7 (left) and the evaluation location, which included a sporting
field, in Figure 7 (right).
The case study is available in full in Annex G.

4.9 Multiple towers case study at sports venue
The purpose of this case study was to determine the maximum field strength contribution from
a new cellular base station to give reassurance of the low levels where the public have
regular access. This base station is one of several located on lighting towers around a sports
ground.
The equipment under test (EUT) was categorised as a Complex RBS. Ambient fields,
including those from the other RBS operating at the sports ground, were not the subject of
this particular investigation. Only the dominant sector pointing into the oval was considered.
The assessment involved determining the location on the sports ground with the maximum
exposure ratio from the RBS under evaluation. This was determined first using a conservative
desktop computation and then verified by on-site frequency selective field strength
measurements. The results were assessed against the General Public reference levels
defined in Australian Radiation Protection Standard (based on the ICNIRP Guidelines).

– 14 – TR 62669 © IEC:2011(E)
The modelled maximum cumulative RF EME levels from the RBS were 0,5 % of the general

public exposure limit. The measured maximum cumulative RF EME levels from the RBS were

0,04% of the general public exposure limit. The measurement result verifies the conservative

outcome of the desktop modelling.

The frequency selective measurements were performed using a hand-held measuring

instrument with integrated isotropic probe. Separate measurements were made of control

channels and across the operating band for each of the technologies supported by the RBS.

Measurements were performed at the computed max field location. Additional measurements

were made at locations around the predicted location of the maximum field strength in order
to confirm the validity of the computation. The maximum and time averaged field strengths

were measured at three heights above the ground where the power output is known.

The “best estimate” assessment scheme has been applied and the calculated and measured
levels reported, including the extrapolation for maximum base station power configuration.
This case study illustrates:
• RF exposure levels on a sports ground from base station antennas on a light tower;
• a comparison of measured and calculated RF exposure.
Structure 2
Structure 4
Structure 3
Structure 1
Figure 8 – Multiple towers case study at sports venue
The subject of this evaluation is shown in Figure 8 (left), a sporting ground/showground at
Perth, Australia. The site consisted of multiple radio base stations located on separate lighting

poles, see Figure 8 (right). The case study is available in full in Annex H.
4.10 In-building base station case study
This case study considers the verification of RF exposure compliance in publically accessible
areas for an indoor distributed antenna system. The system is comprised of distributed
antennas mounted on the ceiling of each floor of an occupied office building.
The equipment under test (EUT) is the individual radiating antennas on each floor in a low
power distributed antenna system. There are no other radiating RF sources at the site under
evaluation. This assessment was performed by the Electromagnetic Environment Lab of
China Mobile Group Design Institute as part of their internal auditing program of mobile
communication base stations. The results of the evaluations are compared against the
reference limits of National standard 8702-88 of the People's Republic of China (GB 8702-88).

TR 62669 © IEC:2011(E) – 15 –
This assessment was performed using computational evaluation and on-site broadband field

strength measurement. The final results were based on the field strength measurement.

The maximum measured RF field strength, found on floor 14, was 13,83 μW/cm2 and the

expanded uncertainty was determined to be 2,26 dB. The “best estimate” assessment scheme

was then applied to compare the measured RF field strength directly with the reference limit.

This demonstrated that the RF field strength is considerably less than the relevant reference

limits. The distributed antenna system installed in this building is therefore in compliance with

National standard 8702-88 of the People's Republic of China (GB 8702-88).

This case study illustrates:
• RF exposure levels inside an office building in close proximity to small antennas which are
part of a distributed antenna system;
• a comparison of field strength measurements and computational assessment.

Figure 9 – Office building IBC case study
The subject of the evaluation, shown in Figure 9, was a distributed antenna system installed

in a Beijing office. Figure 9 consists of a wide shot of the antenna in-situ and shows a close-
up (inset) of an in-building antenna. The case study is available in full in Annex I.

– 16 – TR 62669 © IEC:2011(E)
Annex A
(informative)
Micro cell case study
This annex contains the Micro cell case study referred to in 4.2. This evaluation report is

presented as issued by Ericsson AB and retains its original structure, formatting, layout and

numbering. The standard referred to in the report is IEC 62232.

TR 62669 © IEC:2011(E) – 17 –
Ericsson AB
Evaluation Report
Building Stockholm, Sweden
Björn Hansson
10/4/2008
– 18 – TR 62669 © IEC:2011(E)
Evaluation Report Template
Date of Report:    10th April, 2008

Title:   Micro cell Evaluation Stockholm Sweden

Site Location:    Building, Stockholm, Sweden

Site Coordinates (at Antenna):      removed

Google Earth Hyperlink:                       removed
Evaluation laboratory: Company/Client:

Ericsson EMF Research Laboratory Lars-Eric Larsson
Ericsson AB EMF Management,
SE-164 80 Stockholm System Development & Strategy
Sweden TeliaSonera
Lagergrens gata 7,
SE- 652 26 Karlstad,
Sweden
Evaluation performed by: Date of Evaluation:
Björn Hansson  2008-04-02 to 2008-04-09
Identification number of original report:
EAB-08:027926 Uen
Assessor: Quality Assurance:
___________________________ ______________________

Björn Hansson Martin Siegbahn
Research Engineer Senior Research Engineer
[e-mail] [e-mail]
Tel: [phone] Tel: [phone]

TR 62669 © IEC:2011(E) – 19 –
1. Executive Summary
The purpose of this case study was to assess the RF exposure compliance boundaries from a

particular micro cell installation on a building wall to determine whether they would extend to

a nearby awning. Both the Basic Restrictions and Reference Levels were assessed to

determine the minimum distance from the antenna to the compliance boundary.

The maximum values were compared against international safety guidelines know as ICNIRP

(International Commission on Non-Ionizing Radiation Protection) guidelines. The assessment
establishes compliance against the Basic Restrictions known as Specific Absorption Rate and
the field strength reference levels. SAR testing was performed in a laboratory and frequency
selective field measurements were performed on site.

The Equipment Under Test (EUT) was categorised as a Simple RBS due to the single
technology and single antenna of the micro cell. Nearby base stations, known as secondary
sources, had negligible impact on both SAR and field strength evaluations.
The measured SAR and field strength levels were extrapolated to assess the maximum power
configuration for the site.
The “best estimate” uncertainty model has been applied and the measured levels are reported
including the extrapolation for maximum base station power configuration. The uncertainty is
stated for all assessment methods used.

The compliance boundary distance for general public exposure using the on-site field strength
measurement was 0.8 m, and 0.08 m using the SAR evaluation.
Both the SAR evaluation and the on-site field strength measurements confirm that the general public
exposure compliance boundary from the micro cell antenna does not extend onto the building awning,
therefore access is permitted on the awning.

2. Evaluation Overview
2.1. Site operator information

The test results presented in this report define compliance boundaries for the micro cell base station
antenna flush mounted on the wall. The details of the operator are shown below in Table 2.1.1.

Table 2.1.1: Micro cell operator technology information- primary source
Product Ericsson RBS 2202
Operator TeliaSonera
Transmitting antenna Kathrein 741 316
Electrum building (Isafjordsgatan 26,
Antenna location
SE- 164 40 Stockholm, Sweden)
Technologies GSM 900, GSM 1800
Antenna dimensions (h/w/d) 0.66 / 0.26 / 0.12 m
Antenna mounting 4 m above ground on building wall
Typical output power GSM 900: 34 dBm
(as specified by operator) GSM 1800: 31.5 dBm

– 20 – TR 62669 © IEC:2011(E)
Maximum output power GSM 900: 37 dBm
(as specified by operator) GSM 1800: 34.5 dBm

GSM 900: ch. 34 (941.8 MHz)
Broadcast channels
GSM 1800: ch. 632 (1829.2 MHz)

The TeliaSonera micro cell antenna is located in the vicinity of four other base station antennas,

known as secondary sources. The secondary sources are described in Table 2.1.2 below.

Table 2.1.2: Secondary sources information

Ericsson RBS 2202 (GSM 900/1800) (Telenor)
Products Nokia Supreme (WCDMA 2100) (Telenor)

Ericsson RBS3202 (WCDMA 2100) (3)
Telenor (three color matched antennas)
Operators
3 (antenna above the colour matched antennas)
Kathrein 739 494, 742 212 and 739633 (Telenor)
Transmitting antennas
Kathrein 742 215 (3)
Electrum building (Kistagången 16,
Antenna location
SE- 164 80 Stockholm, Sweden)
Technologies
GSM 900, GSM 1800, WCDMA 2100
Approx. 2 m above primary source (Telenor)
Antenna mounting
3 to 4 m above primary source (3)
GSM 900: ch. 114 (912.8 MHz) (Telenor)
GSM 1800: ch. 800 (1767.8 MHz) (Telenor)
Broadcast / Pilot channels
WCMDA 2100: ch. 10588 (2117.6 MHz) (Telenor)
WCDMA 2100: ch. 10687 (2137.4 MHz) (3)

2.2. Site environment
The micro cell antenna is flush mounted on a building wall approximately 4 m above the footpath. As
shown in Figure 2.2 there are macro antennas (some colour matched) flush mounted on a building
wall approximately 6 m and higher, above the footpath. The awning is the metallic gold coloured
structure below the micro cell antenna.
Secondary sources
Micro cell antenna - The primary
source of this evaluation
Figure 2.2 Photograph of micro cell antenna
2.3. Exposure safety limits
ICNIRP is a body of independent scientific experts who investigate the possible adverse effects of
exposure to non-ionizing radiation. ICNIRP, in conjunction with the World Health Organization (WHO),
developed the ICNIRP Exposure Guidelines.

TR 62669 © IEC:2011(E) – 21 –
This assessment compares results against the ICNIRP Guidelines for Time Varying Electric and

Magnetic Fields for frequencies up to 10 GHz for both Basic Restrictions (SAR) and Reference Levels.

ICNIRP guidelines contain two
...