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Developed by researchers from Amirkabir University of Technology and the Polytechnic Institute of Paris; presenting a method for shielding the human body from 5G technology in mobile phones

 | Post date: 2024/01/7 | 
Researchers from Amirkabir University of Technology, in collaboration with researchers from the Polytechnic Institute of Paris, have succeeded in presenting a new method for shielding the human body from millimeter wave telecommunications technology in mobile phones as part of a successful project.

According to the Public Relations Office of Amirkabir University of Technology, Seyyed Faraz Jafari, a doctoral graduate of the Polytechnic Institute of Paris and this university, and the executor of the project "Shielding the Human Body from Millimeter Wave Telecommunications in Fifth-Generation Mobile Phones," stated: "Due to the rapid growth of wireless technologies, concerns related to physical and mental health during the use of these devices have increased."

He added: "Standards must be observed to ensure the health of operators or consumers when using wireless devices and to prevent any potential risks."

The researcher emphasized that the use of mobile phones or any wireless device, such as cordless home telephones, also requires compliance with standards. He stated: "The World Health Organization (WHO) determines a specific amount of radiation to ensure that human exposure to radiation from wireless devices does not exceed this permissible limit."

He further emphasized: "The role of engineers in the field of electrical engineering with a telecommunications focus is crucial in developing methods for measuring and calculating the amount of radiation in the human body, especially in the high-frequency range above 6 gigahertz in 5G technology, due to the deep penetration of surface waves inside the body. These engineers must model complex equations and design and develop the necessary measurement devices and equipment to ensure that radiation remains within safe limits for human health. These efforts ensure important issues such as public health and safety in wireless technologies."
Jafari continued: In a telecommunications communication, the signal received by the user from the telecommunications tower or sent from the user's device to the tower raises concerns about the amount of EMF (electromagnetic) energy imposed on human users. At frequencies higher than 6 gigahertz, where 5G communication systems will operate in the future, two changes are expected that may increase human user concerns.

He emphasized: First, more transmitters will work in base stations (telecommunications BTS towers) and in mobile devices. Second, narrow beams will be used as a solution to compensate for further weakening in higher frequency bands.

He added: In 5G technology, data transmission occurs at higher frequencies compared to previous generations of telecommunications such as 4G and 3G. However, contrary to public concerns that this increase in frequency will cause more harm to the human body, it should be noted that the penetration depth of these waves inside the human body is less compared to waves at lower frequencies, meaning that these waves only penetrate the outer layer of the human body. Thus, vulnerable points of the body, such as the skin and eyes, are considered.
According to this researcher, finding the exact level of radiation exposure is much more difficult than in previous generations of telecommunications, as there is currently no accurate method for these waves.

He said that the aim of this project is to provide a method for determining the amount of radiation exposure of the human body from mobile phones operating at 5G frequencies.

Jafari continued: In this thesis, two methods have been presented for measuring radiation exposure in the human body caused by mobile phones operating at frequencies higher than 6 gigahertz (5G).

Referring to the first method, he said: The first method, which is an invasive method (measurement inside a liquid equivalent to the human body), is an improvement over the method previously used to determine the specific absorption rate (SAR) caused by devices operating at frequencies below 6 gigahertz, but in this thesis, this method has been upgraded for frequencies above 6 gigahertz.

He added: But the second method is a novel method that, for the first time, has been presented non-invasively (measuring the electric field around the antenna) to determine the amount of radiation exposure caused by a mobile phone when it is very close to the body (such as when a person is talking on a mobile phone).

He continued: The measurement of radiation exposure in the human body is carried out in laboratory environments, especially in calculating the absorbed power density (APD) caused by a mobile phone (or antenna) operating at the desired frequency, alongside a liquid or solid model equivalent to the human body.
He continued: The proposed methods pave the way for a new model of assessing APD, considering the coupling effect between the antenna and the human body, to determine the level of human body radiation exposure in the vicinity of mobile phones operating at frequencies above 6 gigahertz (5G telecommunications).

Jafari emphasized: To ensure the validity of the proposed methods, collaboration with researchers in France has been planned to carry out practical measurements of human body radiation exposure using these methods.

He explained: One of the important features of this project is considering the coupling effect between the antenna and the human body when the antenna is near the human body and its impact on human body radiation exposure. This feature is crucial for accurately measuring human body radiation exposure under real communication conditions. This project, by taking these features into account, will help improve the accuracy and efficiency of assessing human body radiation exposure to electromagnetic waves.

The researcher added: Although devices for measuring electric and magnetic fields already exist, the use of the methods presented in this thesis is novel and has not been used in the world so far.

Dr. Jafari continued: Competitive advantages of the project have shown that the proposed method, which involves measuring inside a human tissue model along with field reconstruction, is an efficient and accurate method for assessing absorbed power density, considering coupling effects and multiple reflections.
He pointed out: Since the size of the sampling plane in the proposed method is much smaller compared to the free-space wave plane method, the proposed method is optimal in terms of time and computational efficiency.

He said: This research has provided valuable insights for assessing absorbed power density in next-generation wireless telecommunications and field compliance testing methods for products operating in these frequency bands. This project helps develop and improve the safety and health of wireless technologies by introducing improved and innovative methods for assessing risks associated with wireless technologies.

It should be noted that Dr. Reza Saffari Shirazi and Dr. Gholamreza Moradi, faculty members of Amirkabir University of Technology, and Dr. Joe Wiart and Dr. Alain Sibille, members of the faculty of the Polytechnic Institute of Paris, have been the advisors of this project.