Characterization of Cellular Base Stations

The expansion in the mobile communications sector is progressing steadily. Many metrological challenges are associated with the approval procedures for new cell sites and operation frequencies. The primary objective is to comply with the legally specified emissions. In order to nevertheless ensure excellent network coverage, the propagation characteristics in the vicinity of the base station and the structural attenuation values of the site must be precisely known. To provide a solid and realistic database for propagation simulations, measurements at real sites are essential.
In addition, it is imperative that the future densification with base stations, especially in urban areas, complies with the legally prescribed limits for electromagnetic alternating fields. In this way, damage to the health of people or animals who are in the vicinity of the base station can be ruled out. For example, this must be ensured for employees in an office building on whose roof one or more base stations are installed. This is summarized under the term electromagnetic environmental compatibility. The assessment is carried out on the basis of various standards such as:

• EN 50413:2019: Basic standard on measurement and calculation procedures for human exposure to electric, magnetic and electromagnetic fields (0 Hz – 300 GHz)
• EN50499:2019: Procedure for the assessment of the exposure of workers to electromagnetic fields
• EN50647:2017: Basic standard for the evaluation of workers’ exposure to electric and magnetic fields from equipment and installations for the production, transmission and distribution of electricity
• IEC/IEEE 62704-(2/3):2017: Determining the Peak Spatial-Average Specific Absorption Rate (SAR) in the Human Body from Wireless Communications Devices, 20MHz – 6GHz – Part 2 and Part 3

In line with this, Sykno, as an expert for high frequency technology and high frequency systems, now offers the characterization of mobile radio cells based on field strength measurements. We have the latest measurement technology (Narda SRM-3006) in the relevant frequency range from 400 MHz to 6 GHz and thus cover all currently available frequency bands of mobile radio in Germany. The measurement of electric field strength or power can be performed with respect to an axis, or isotropically, thanks to a special field probe. A particular advantage of the measurement system is the code-selective measurement, which specifically decodes and measures the signals of the desired cell sector. Thus, interfering signals and interference from other cells can be suppressed. Code-selective measurement is currently available for UMTS, LTE (TDD and FDD) and 5G NR.