HJ 1151-20205G Mobile Communication Base Station Electromagnetic Radiation Environmental Monitoring Method (Trial) (English PDF)

2.1 Base station

A land station in the land mobile service is a wireless transceiver equipment that serves a cell or multiple cells on the same site. Base station passes without the wire interface provides a wireless channel with the terminal.

2.2 5G user equipment Terminal equipment that carries 5G mobile communication services.

2.3 Electromagnetic radiation environment-sensitive target

Objects that need to be focused on in the environmental impact assessment and monitoring of electromagnetic radiation. Including houses, schools, hospitals, office buildings, factories, etc.

The building where you live, work or study.

2.4 Application scenario

5G mobile communication application scenarios include. enhanced mobile broadband (eMBB), ultra-high reliability and low latency communication (uRLLC), large Large-scale machine communication (mMTC), such as data transmission, video interaction, game entertainment, virtual shopping, smart medical, industrial applications and vehicles Scenes such as networking.

3.1 Environmental conditions

The environmental conditions during monitoring should meet the requirements for the use of monitoring instruments.

3.2 Monitoring equipment

3.2.1 Basic requirements

The working performance of the monitoring instrument should meet the requirements of the electromagnetic field to be measured. The detection method of the monitoring instrument is the root-mean-square detection method.

The reading is the average of any continuous 6 minutes.

When monitoring, a frequency-selective electromagnetic radiation monitor should be used, and the monitoring frequency should be selected when the transmitting antenna of the mobile communication base station under test is working.

Line frequency band.

When conducting electromagnetic radiation environmental monitoring for mobile communication base stations with 5G and other network standards at the same site, use frequency-selective electromagnetic radiation the list mode of the radio monitor can obtain the electromagnetic radiation field strength data of 5G and other network standard mobile communication base stations.

During monitoring, if the probe (antenna) of the monitoring instrument is an isotropic probe, it should meet the isotropic index requirements in Table 1; if If a non-isotropic probe is used, the influence of antenna directivity should be considered, and the antenna factor and other parameters should be synthesized during the result processing.

Adjust the detection direction until the maximum field strength value is measured; the support of the monitoring instrument should be made of a non-conductive material that is not susceptible to moisture.

3.2.2 Basic requirements for electrical performance of frequency selective electromagnetic radiation monitor the frequency-selective electromagnetic radiation monitor refers to the ability to receive and process the spectral components of a specific emission within the response frequency range of the instrument the basic requirements for electrical performance of the field quantity monitoring instrument are shown in Table 1.

Table 1 Basic requirements for electrical performance of frequency selective electromagnetic radiation monitor

4.1 Data collection

Before starting the monitoring work, the basic information of the tested 5G mobile communication base station should be collected, including. base station name, operating unit, construction site Point, transmitting frequency range, antenna support type, number of antennas, operating status and height of antenna from the ground, etc.

According to the nature and purpose of monitoring, other information can be collected, including. latitude and longitude coordinates, transmitter model, nominal power, and actual transmission Power, antenna gain, average load, antenna downtilt angle (mechanical downtilt angle electronic downtilt angle), antenna lobe width (horizontal width, vertical Straight width) and antenna pattern and other parameters.

Mobile communication base stations with other network standards at the same site should also collect the same basic information.

4.2 Monitoring factors

The monitoring factor of the electromagnetic radiation environment of the mobile communication base station is the radio frequency electromagnetic field, and the monitoring parameter is the power density.

4.3 Monitoring points

The monitoring points should be arranged at the electromagnetic radiation environment-sensitive targets within the coverage of the antenna of the mobile communication base station, and should be arranged in public residential areas first.

Live, work or study at the closest place to the antenna, but it is not suitable to be deployed where tools (such as ladders) or special methods (such as climbing) are needed to reach s position.

When monitoring in a building, the monitoring point can be placed at the position of the window (balcony) facing the base station antenna, and the probe (antenna) tip of the monitoring instrument the end should be within the window frame (balcony) interface, and it can also be arranged in other indoor locations. Between the monitoring instrument probe (antenna) and household appliances and other equipment the distance is not less than 1m.

4.4 Monitoring height

The probe (antenna) of the monitoring instrument is 1.7m away from the ground (or standing plane). You can also select the monitoring height according to different purposes, and Noted in the report.

4.5 Monitoring working conditions and 5G terminal equipment

During monitoring, the monitored mobile communication base station should be in normal working condition, and the 5G terminal equipment should be built with the monitored 5G mobile communication base station.

It is connected to at least one typical application scenario.

During monitoring, the probe (antenna) of the monitoring instrument is placed on the support of the monitoring instrument, and the distance between the tip of the probe (antenna) and the operator's torso not less than 0.5m, and kept within the range of 1m to 3m with 5G terminal equipment; avoid or minimize other sources of electromagnetic radiation that occasionally occur nearby Interference and monitoring instrument bracket leakage current.

4.6 Monitoring readings

The monitoring time for each monitoring point is not less than 6 minutes, and the average value of the monitoring instrument is read.

4.7 Record

4.7.1 Record of base station information

Record the relevant information collected in Section 4.1.

4.7.2 Records of monitoring conditions

Record the ambient temperature, relative humidity and weather conditions.

Record the monitoring date, monitoring start and end time, monitoring personnel, monitoring frequency range, monitoring instrument and probe (antenna) model and serial number, Monitoring instrument and probe (antenna) calibration/verification certificate (report) number.

Record application scenarios during monitoring, 5G terminal equipment model, quantity, application scenarios, etc.

4.7.3 Record of monitoring information and results

Record the schematic diagram of the site monitoring points, and mark the 5G mobile communication base station antennas, monitoring points and other known electromagnetic radiation sources.

Record the name of the monitoring point (or latitude and longitude), the vertical distance and the horizontal distance between the monitoring point and the 5G mobile communication base station transmitting antenna and monitoring data.

Keep the spectrum distribution map during monitoring.

Refer to Appendix A for the content and format of on-site monitoring records.