Electromagnetic field radiation for fifth generation base station using millimeter wave antenna array

• Main Author: Ibrahim, Nor Adibah
• Format: Thesis
• Language: English
• Published: 2021
• Subjects: TK Electrical engineering. Electronics Nuclear engineering
• Online Access: http://eprints.utm.my/id/eprint/102308/1/NorAdibahIbrahimPSKE2021.pdf.pdf; http://eprints.utm.my/id/eprint/102308/; http://dms.library.utm.my:8080/vital/access/manager/Repository/vital:149167
• Institution: Universiti Teknologi Malaysia

Pico-cells and indoor base stations in various frequency bands are required as part of the construction of the fifth-generation (5G) network. Electromagnetic fields (EMF) are emitted by these base stations, and there is worry regarding their impact on the human body. The amount of acceptable radiated EMF is measured by specific absorption rate and free space power density as specified by international regulatory bodies. Therefore, the goal of this thesis is to look into the quantity of radiation emitted by antenna arrays in an indoor and hallway environment based on power density. Seven distinct antenna arrays operating at 2.6 GHz and 28 GHz have been devised and constructed using Computer Simulation Technology. In the power density measurement for indoor and hallway environments, the designed antennas are used as a transmitting antenna. The power density values need to verify whether the compliance limits set by the International Commission bodies such as the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and Federal Communication Commission (FCC) bodies are complied with. According to the findings, higher number of the antenna elements would increase the antenna gain and received power, resulting in a higher power density. The gain of the 8×8 antenna array operating at 28 GHz is 23.80 dBi, compared to 17.75 dBi for a 4×4 array. Furthermore, the power density of the 8×8 array is substantially higher than that of the 4×4 array, with the power density of the 8×8 and 4×4 arrays being 6.80×10-6 W/m2 and 2.59×10-6 W/m2 respectively for indoor environments at 1 m distance. The measured power density at 28 GHz was found to be within the ICNIRP and FCC regulation’s permissible limits. Comparative test conducted shows that the indoor environments has a higher power density than hallway environment. The measured power density for the 8×8 antenna array at 1 m distance for 28 GHz in the indoor and hallway environments are 6.80×10-6 W/m2 and 6.65×10-6 W/m2 respectively. Based on the allowable power density by ICNIRP and FCC, a compliance distance of 1.37 m was recorded for 8×8 antenna array at maximum power transmission of 30 dBm. This study helps to determine the compliance distances between users and radio base stations in Malaysian indoor and hallway environments.