5G EMF Measurements: The Prerequisite to Deploy 5G

Introduction by Dr. Haziran Abdullah

• Dr. Haziran Abdullah from International Islamic University Malaysia (IIUM) is the MC and technical chair for ITPA ECONSORT, VTS Malaysia chapter.
• The webinar is organized by CONSORT VTS Malaysia chapter and co-organized by ITPE, MICROM VT, Rohde & Schwarz, MWCWT Research Group, and IIM WCSB Research Group.
• The registration link is in the flyer.
• The seminar was moved online due to the COVID-19 pandemic.

Welcoming Remarks by Dr. Madani Rosli

• Dr. Madani Rosli from MMU, the chair of IEEE Consult VTS Malaysia chapter, delivers welcoming remarks.
• The chapter has organized useful webinars and activities during the COVID-19 pandemic.
• The Ethiopian Society, a chapter in Ethiopian Malaysia sections, has over 130 members.
• The chapter was established in 1992 with around 60 members and reached around 600 members in 2015-2016.
• Students are encouraged to join the chapter for mutual assistance.
• The chapter has 16 executive committee members from various industries.
• The chapter won the outstanding lecture award last year.

Introduction of the Speaker

• Mister Anwar Faiz Osman is the regional system and application engineer from Rohde & Schwarz.
• He has about 17 years of experience in wireless and mobile network testing and is a senior member of IEEE.
• He is involved in the Malaysia 5G task force and is a chairman for the 5G ecosystem and timeline sub-working group.
• He is the vice-chairman of MTSFB IMT and future network working group and a technical drafter for MTSFB 5G specifications.

Abstract of the Webinar

• 5G uses beamforming and frequencies above 3 GHz to achieve required throughput, coverage, and reliability.
• Concerns exist about the effect of electromagnetic radiation on human health.
• Deployment is delayed in some countries until radiation levels are proven to be below specific thresholds.
• The webinar compares two measurement techniques for EMF measurements, discusses their pros and cons, and provides example measurements from the field.

Presentation by Anwar Faiz Osman: 5G EMF Measurement

Agenda

1. EMF Measurement Introduction:
   • What is EMF and why is it important for 5G deployment?
   • Who determines the global EMF safe level?
2. EMF Standardization:
   • Derivation of the EMF limit.
   • Real-case 5G EMF implementation.
   • Different approaches by countries on determining the EMF exposure limit.
3. Legacy EMF Measurement:
   • Various EMF measurement methods in the past.
   • Short-term and long-term EMF measurement methods.
4. Comparing Frequency Selective vs. Code Selective EMF Measurement Techniques:
   • Differences between the two methods.
   • Why code selective is the suitable measurement method for 5G rollout.
5. 5G EMF Test Solution:
   • 5G EMF code selective method using RF scanner and UE device.
6. Example of Field Measurement Results:
   • Sample field test and the cooperation of 5G EMF in a site.
   • Real measurement examples.
7. Learning and Conclusions.

EMF Measurement Introduction

• EMF (Electromagnetic Field) is measured in volts per meter (V/m).
• It measures human exposure to electrical fields, especially in sensitive areas.
• Evidence is needed to show that EMF exposure is below a certain threshold defined by law or regulators.
• EMF measurements are used to dispel doubts, fake news, and health and safety concerns, avoiding delays for 5G rollout.
• Those in the 5G industry have a responsibility to ensure the technology doesn't pose health hazards to the public.

Scope of 5G EMF Measurement

• EMF measurement can be done indoors or outdoors, short-term or long-term.
• Applications include comparing exposure from different transmitters, public information, and data recording.
• More complex technologies like 4G and 5G require more sophisticated measurement methods.

Electromagnetic Spectrum

• Frequencies in MHz up to GHz are in the non-ionizing range, which doesn't affect the mutation of human tissue.
• Sunlight, ultraviolet, and gamma rays are ionizing and have a direct effect on human tissue.
• Cellular frequency ranges are under non-ionizing radiation; however, the power levels need to be controlled to avoid thermal effects on the human body.
• This chart is provided by the Malaysian technical standard for MCMC and TRSB.

Importance of EMF for 5G

• In Switzerland, the rollout of 5G was halted over health concerns.
• The public wanted assurance from the government that EMF data was verified.
• Switzerland developed a method acceptable to the public and continued with the rollout.
• 5G EMF measurement is often a prerequisite before deploying 5G.

Determining the Safety Level of EMF Exposure

• WHO is a global reference for EMF.
• WHO states EMF exposure levels below the ICNIRP international guidelines do not appear to have known health consequences.
• WHO follows ICNIRP guidelines.

EMF Standardization

• Scope when defining the standard:
  • Influence of EMF on humans.
  • Frequency range.
  • Field strength and power density.
  • Exposure time.
  • Modulation (important for code selecting method).
  • Co-location and other radio sources.
  • International recommendations (WHO, ICNIRP).
  • Technical standardization on measurement methods (IEC, IEEE).
  • Regional or country limits and measurement procedures.

Derivation of the Limit

• ICNIRP defines the guideline of limited exposure on human health due to EMF and has a refreshed version of 2020.
• IEC 62232 defines 5G base station measurement for EMF, giving clauses on the method using a dedicated NR decoder.
• It depends on the SSB (Synchronization Signal Block) and includes an extrapolation factor.
• Switzerland's Federal Institute of Metrology (METAS) defines the measurement method for 5G NR precision up to 60 GHz.
• METAS regulator in Switzerland has selected the code set method as a reference method.
• Malaysia bases its standards on the technical code from the Malaysian technical standard for MCMC.
• The regulatory body is MCMC.

Reference of Exposure Limit from ICNIRP 2020

• The EMF value is covered by different parts of the spectrum.
• ICNIRP defines limits for occupational workers (higher limit) and the public (lower limit).
• At mid-band or high-band levels, the limit defined by ICNIRP for occupational is about $50 W/m^2$ and for the public is $10 W/m^2$.
• There are signage categories the operator needs to apply near the base station, indicating public level, official level, or no-go zone.

National Standardization

• Some countries, like Switzerland and Germany, have stricter limits.
• Lowering the limit for EMF means the power from the base station will be lower, requiring more base stations to cover an area.

Legacy EMF Measurement

• Frequency selective measures total power (RSSI), while code selective measures power on known signal (RSRP).
• The measurement setup includes a measurement human, a probe (antenna), and knowledge of the antenna factor.
• The measurement of RSSI or RSRP is converted into field strength using software in the instrument.

Various EMF Measurement Methods in the Past

• Fast EMF Survey:
  • An EMF snapshot to estimate the EMF in the area.
  • Fast and brief overview of relevant transmitters.
  • Uses a proper meter, a centimeter, or a spectrum analyzer.
  • Provides a live result and is a fast analysis ahead of detailed investigation.
  • Measurement can be done automatically using an instrument and an isotropic antenna.
• Transmitter Site:
  • Measures EMF exposure from a new transmitter.
  • Analysis or worst-case coming from that new transmitter.
  • Considers maximum traffic and involves detailed settings for signal parameters.
  • Requires meticulous planning and knowledge of theory to extrapolate for the worst case.
  • Verifies the safe distance and addresses public concerns about new transmitters.
• Transmitter Site Analysis (Multipoint Method):
  • Defined by reference e n 5040 or e n 50492.
  • Regulation-specific and requires strategy for sampling, averaging, max detection, or RMS.
  • Measures points typical to the human body (hip, abdomen).
  • Measures total exposure ratio of all measurement front.
  • Uses an isotropic antenna and measures at various heights (70 cm, 150 cm, 10 cm).
• Steering Method (Pivoting):
  • A simplified version of the multipoint method.
  • Recommended by some countries (Switzerland).
  • Evaluates the special maximum field.
  • Involves pivoting the antenna to get the maximum value of the EMF.
  • Done with handheld measurement and requires live measurement and maximum value capture.
  • Typically done one service at a time (LTE, 3G).
• Long-Term Analysis:
  • Evaluates emission of hours, days, weeks, or months.
  • Shows the chronology of different services in terms of EMF exposure.
  • Analysis of overall emissions per service and per operator.
  • Can be made into a fully automatic operation.
  • Typically done at a fixed installation site monitored by the regulator body.
  • Proves the validity of short-term measurement and provides assurance to the public.

Frequency Selective vs. Code Selective EMF Measurement

• Frequency selective measurement measures a pure power spectrum and doesn't discriminate between signals (2G, 3G, 4G, 5G).
• It converts all the power (RSSI) into electrical field strength.
• Code selected method identifies the technology, decodes the carrier, and measures the EMF for each bit (RSRP).
• This is the preferred method in Europe for measuring 5G exposure levels.
• For the same sector PCI, different SSB index exposure levels will not be the same across the area.

Importance of Measuring EMF in 5G

• 5G uses beamforming because of higher frequencies.
• Beam index is used for synchronization signal and data signal.
• One PCI can have multiple SSBs, and the exposure level varies across the area.
• The antenna system for 5G is more intelligent and creates a narrow beam to focus the power.
• Field strength hotspots can occur in the narrow main loop of the beam.

How Equipment Measures 5G EMF

• 5G has an always-on signal (SSP).
• EMF measurement exposure needs to measure always-on signal (RSRP).
• The exposure factor needs to be applied to calculate the full maximum exposure.
• 5G is packet-switched, so the resource block power is only measurable when active traffic occurs.
• PDSCH (Physical Downlink Shared Channel) may use different beam compared to SSB.

Characteristics of Frequency Selective Method

• Maximum hold is required to accumulate all the signal maximum levels across the time.
• Spot measurement may not give the total idea of the maximum exposure.
• The signal can come from any sources, not just 5G.
• Frequency selective measurement is based exclusively on power spectrum measurement.
• Procedure does not decode or assign to any technology or operator or any cell.
• Procedure cannot identify which signal is contributing at what portion of the radiation.

Characteristics of Code Selective Method

• Code selective measures power on known signal (RSRP).
• Code selective measurement decodes the signal and assigns a level of technology, site sector, and SSPB information.
• Suppression factor needs to be applied to calculate the full maximum traffic exposure level.
• The code selective helps operators better optimize the power distribution coming from the position.
• Optimization team can help identify the setup to ensure good coverage and pass AMFME.
• A code selection method produces maximum possible capacity and coverage based on this method.
• With the same cell ID, you can have different SSP pin and different reference power.

EMF as A Portion Factor: 4G vs 5G

• IEC uses average of assignment, normalized to the power of one resource element.
• For LTE with a 20 MHz channel, the calculation is 100 resource blocks times 12 resource elements.
• If you have a total power per sector of $40 W$, the calculation to get the extra portion factor will be: $10 \times log(\frac{40}{\frac{40}{1200}})$

Five Factors of 5G Image Separation

1. The power covered by the sector (120 degree) is no longer uniform.
2. Divided into sub-sectors with narrow SSBB.
3. High, low, or no power.
4. 5G uses beamforming to overcome the path loss at higher frequencies.

• TDD (time division duplexing) for mid band or high band deployment of a 5 G.
• The signal is shared between the uplink and downlink.
• Only need to focus on the downing time when wanting to see the exposure.
• The equation factor needs to be times by 0.5 because that's what most sequence will be. Downing, uplink, downing, uplink.
• Factors needed to consider for 5G image separation compared to 4G.

Steps for 5G EMF Measurement as defined in IEC 62232

• Step 1 is to apply the acceleration factor and includes the following factors:
  • SSB (bandwidths of 3.6 up to 7.6 Mhz, depending on the subcarrier spacing).
  • Check the subcarrier spacing: 15 kHz, 30 kHz, 60 kHz.
  • A difference of clear spacing will have different separation factors.
  • Need to find if the operator is transmitting a 3.5 GHz signal by obtaining information about their subcase.
• The beam gain offset between SSP and data beam (IECC2P2) power control will be applied by the business but there is no difference if the SSB is the same bit.
• Take up and update relation factor in TDD, the dialing relations especially in the 78 or different factors will be from four to one. The 0.8 acceleration factor has to be added into the mix and consideration factored into the time division.

Step 2 With Multiple SSB from A Base Station

• Measurement tool needs to measure all of the SSP power for a certain area.
• Sensitivity can be classified as schools, residential spaces, coffee shops - it is really up to the regulator in how they define those areas.
• Each home needs data and needs to prove that the explosion factor coming from a base station is safe.
• All SSP beam should be able to be detected, as standard
• Both a direct path alignment can be measured, and reflected signals

5G EMF Test Solution

• Passive measurement is recommended.
• The Rohde & Schwarz scanner is the preferred TSM as 6
• Controlled by Collipore Android phone (older version), not exclusive to any 5 series.
• Connected by Bluetooth. This phone is our own polypop phone. And we used to control.
• Scanner includes the scanner itself and a PC inside (small PC internal).
• Passive calibration receiver to the highest accuracy.
• Scanner can automatically detect the 5G PCI and the scanner index.
• Phone is set to airplane mode, meaning there will be no power affecting from the phone to bluetooth during the scan.
• The measurement is done by the scanner through the Bluetooth to the mobile phone.
• We want to find the line measurement and what is the max.
• Set to export and put it in CSV through all SSP together by separation, is what we intended to add to the measurement results.

Passive Measurement System Procedure

• First, have a scanner, connect to an antenna, conduct measurements on the synchronization signals and then decode the operator information and carrier with the antenna gain and or factor that has to be calculated during the measurement.
• Then the maximum extraction, as each PCI must be scanned until the area is covered the best you can with the maximum reading. So each ssb is measured until they have their factor.
• Store or pivot it with each with the scanner, then it calculates everything at the SSB at the PCO with this equipment.
• We export the data depending on which code the regulator chooses for the test.

Characteristics of Passive Measurement System

• Equipment has the 5 G carrier detection
• Measurement for scanner displayed through the phone is used for a code selective setup with SSP index power level based on the PCI. (Channel number is available). Older phones can conduct passive payments with Bluetooth technology in this setup.
• This can also measure maximum value in live scan to the location of the signal when you go into pivot until you found the area.
• Measurement is marked, summarized, exported, and will have a timestamp to show the export measurement in C S S V.

Measurement Considerations

• Start equipment by pivot scanning to find max cue strength as a pivoting test to perform a legacy management procedure.
• The output data will show measurement in timeline or value to the max measurements.
• There is also an antenna that can show the probe antenna factor that we use to be added to the system in calculation to provide data as results.
• Does not matter what brand of antenna is needed that the frequency rates is scanned/used.

Field measurements with conclusions

• In testing with the UTMWCC, there was access to the lab as stakeholders to provide results indoor.
• Testing done in DG 5g overlook in the cyber Java space indoor, pretty close to setup.
• There were outdoor field trials in conjunction with 5 G and core existence.
• Did show 5 G precision signal data, and can show the difference. In these trials, to show LTE has lower reading because it is uniform. Higher reading because it is the pencil beam from 5 G.
• Google Earth can be used to show the test and the scanner route, showing the live measurements.

EMF Evaluation Example

• Location Automation with Latitude Location.
• There was maximum exposure for SSB @300 at 27. 8 mV/n, with over thirty seven point four minutes for the second setting.
• Calculations will be made from the equation. (From all these beam measurements, as a summation of all is needed). 0.0467 will be the total ESSB in a Volt Meter setting.
• FTDC is 0.8, FTWR - 1.
• FPW (as it has bandwidth @100 sub carrier subfield spacing) is 3. 276 based a table the I E C Provided.
• Total 5 GMF at a set will be one point six seven (Volts Per Meter) - to the Latitude Longitude statement during that measurements.

Conclusions

• Required to find the EMF readings under the limits. (Responsibility to do so). Scanner receivers is perfect for what’s been calibrated with this code.
• Factor should identify what factor it can scan and create to add a code for those elements.
• Scanner can find each network optimized with optimization and scanners to balance the maximum power the same while there is a code for management.
• Operators team can identify a network while passing some deployment
• Operators optimizing with maximum capacities and coverage while being safe. (Which is code and test method). End. Now in Q&A.