
The electromagnetic field and people ON PHYSICS, BIOLOGY, MEDICINE, STANDARDS, AND THE 5G NETWORK We are pleased to present this publication, which discusses, in a compre- hensible manner, the most important issues related to the radio-frequency electromagnetic field. It is those fields that allow us to enjoy radio and television broadcasts and to use mobile phones. Thus, it is the basis for a trouble-free and fast flow of information, which is the foundation of our civilization nowadays. This publication is divided into four sections. The first three sections answer the most frequently asked questions about electromagnetic waves. What are they? What are their effects on the human body? How are they measured and what regulations apply to them? The fourth section briefly explains the relationship between the electromagnetic field and telecommunication, and what the next generation of cellular networks, i.e. 5G, is. We are sure that this publication will help everyone interested in this topic to understand what the electromagnetic field is and how we can use it for the good of Poland. We hope you will find it interesting! Ministry of Digital Affairs Project coordinator Publisher: Wojciech Hałka National Institute of Telecommunications Chief Editor ul. Szachowa 1 Łukasz Lamża 04-894 Warsaw, Poland tel. +48 22 5128 100 Assistant editor e-mail: [email protected] Łukasz Kwiatek www.itl.waw.pl Proofreading Maciej Szklarczyk © Copyright by Ministry of Digital Affairs, Warsaw 2020 Infographics Lech Mazurczyk Additional illustrations Paweł Woźniak The project is financed from Preparation: an earmarked grant funds National Institute Graphic design and typesetting of the Ministry of Digital Affairs of Telecommunications Adrian Hajda Print ACAD, Mirosław Przywózki ul. Sosnowa 34a, 05-420 Józefów, Poland I. Physics 6 Introduction 8 I.1 Electromagnetic field, electromagnetic waves 14 I.2 From radio waves to gamma rays: the electromagnetic wave spectrum 22 I.3 Power, absorption, scattering 28 I.4 Natural sources of the electromagnetic field 32 I.5 Man-made sources of the electromagnetic field 38 INFOGRAPHIC: Some applications of electromagnetic waves 40 I.6 How does a mobile phone work? II. Biology and medicine 49 Introduction 50 II.1 Impact of the radio-frequency electromagnetic field on biological systems 58 II.2 Impact of microwaves and radio-frequency waves on humans 67 INFOGRAPHIC: Dominant areas of research on health effects of microwaves and radio-frequency waves III. Standards and measurements 71 Introduction 72 III.1 Standards and safety 82 III.2 Standards applicable to the electromagnetic field 89 III.3 Methods of measurement of the electromagnetic field 95 III.4 Measurement of the electromagnetic field in Poland and worldwide IV. 5G technology 105 Introduction 106 IV.1 Cellular technology generations 110 IV.2 Assumptions and objectives, planned parameters of 5G 114 IV.3 Applications of 5G 122 INFOGRAPHIC: Examples of 5G applications 124 IV.4 What are the benefits of 5G? 126 Glossary 129 Authors and consultants Supervisor Jerzy Żurek, PhD, National Institute of Telecommunications Science and technology consultants Rafał Lech, PhD, DSc, a professor at the Gdańsk University of Technology Piotr Kowalczyk, PhD, DSc, a professor at the Gdańsk University of Technology I. Physics Introduction • The electromagnetic field is one of the fundamental elements of the natural world. It occursnear all electrically charged particles, moving charges, and permanent magnets. • In the electromagnetic field, its excitations – electromagnetic waves – move. These waves carry energy. • According to modern physics, such a wave can also be considered a flow of particles – photons. • Electromagnetic waves can differ in length – i.e. the distance between successive crests – which determines their frequency – i.e. a measure of how many times in a fixed unit of time, usually 1 second, the crest of a wave passes through a given point. Electromagnetic waves of different lengths/frequencies also have different energy. The longer the wave (and therefore the lower the frequency), the lower the energy of one photon. • The division into ionizing and non-ionizing radiation is important. It is related to the photon's ability to ionize, in other words to induce a reaction that causes the conversion of an electrically neutral atom or a chemical particle into a charged molecule i.e. an ion. In practice, this means that ionizing radiation can cause chemical reactions, thus influencing the molecules in the cells of living organisms, e.g. DNA. • Electromagnetic waves in the radio and microwave frequency ranges are non- ionizing. Their most important applications include: AM, FM, and DAB radio, digital terrestrial television, mobile telephony, Wi-Fi, Bluetooth, and radar. In medicine, however, ionizing radiation is more commonly used, e.g. in X-ray examinations or cancer radiotherapy. • The basic quantities that enable a quantitative description of the electromagnetic field are electric field strength E, magnetic field strength H, and power density S of the electromagnetic wave. • Waves traveling (“propagating”) in a space interact in different ways with objects found in the space. This leads multiple reflections of the wave, refraction, refraction, interference, attenuation and scattering. • As a result of these phenomena, the field strength at a given point, especially in an urban environment, can be difficult to predict and can change constantly, even with a fixed source (antenna) position. • There are numerous natural sources of the electromagnetic field. • Earth is the source of its own magnetic field, which is created in the planet's liquid core. In the atmosphere, various types of magnetic and electric fields are generated, the result of which in natural electric discharges (lightning). • Every body with a temperature exceeding the temperature of absolute zero (or, in practice, every body in the Universe) is also a source of so-called thermal radiation. In the case bodies with temperature equal to room temperature, thermal radiation is in the infrared range. • For almost 150 years, humanity has been using, to an ever greater extent, devices and installations that are sources of the electromagnetic field. • In Poland, the first radio broadcasting stations were built in the 1920’s. In 1923, a broadcasting center was established near Warsaw and, in 1927, broadcasting stations were built in Cracow, Poznań, and Katowice. • Every electrical device – such as a TV set, a hairdryer, a refrigerator, an induction hob, a laptop, or a mobile phone – is a source of the electromagnetic field. • The basic unit of organization of the mobile network is a "cell": an area covered by one base station. • In a base station there are sector antennas that are used for communication with the users, and radio link antennas for communication with other base stations or the base station controller. • A terminal (i.e. any device that uses a cellular network, e.g. a mobile phone) is also a transmitter whose operating power increases with its distance from the base station. The power of the terminal is thus the greatest at the cell boundary and decreases as the user approaches the base station antenna. 8 I.1 Physics I.1 Electromagnetic field, electromagnetic waves RAFał PAWLAK The Universe, according to the most Four interactions likely evolution model referred to as the "Big Bang," The electromagnetic field is one of emerged about 14 billion years ago. From the very the four interactions naturally observed in nature dense and hot singularity emerged space, time, that are of fundamental importance, the so- matter, energy, and their mutual interactions. In the called fundamental interactions, which cannot be Universe expanding over the billions of years that reduced to other, more basic interactions. Those followed, electromagnetic phenomena play a great interactions are: role. They belong to numerous, extremely important and core processes, which from the very beginning • the gravitational interaction (classically, it is formed and continue to shape the Earth's natural a universal gravity force associated with attraction electromagnetic environment, being its integral between molecules with mass); part. The energy accompanying electromagnetic • the weak nuclear interaction (responsible phenomena, which is one of the oldest forms of for some forms of decay of atom nuclei and energy in the Universe, was one of many factors elementary molecules); that influenced the evolution of our planet and the • the strong nuclear interaction (occurs in atom life on it. nuclei, mediating between the constituent The electromagnetic field undoubtedly elementary molecules); and accompanies humans not only "always", but also • the electromagnetic interaction (occurs between everywhere, in every part of their lives. Humans, charged molecules). like our entire planet, are located in the vicinity of a giant source of electromagnetic waves of a very There are even some similarities between the wide spectrum, which is the Sun. The human electromagnetic interactions and the gravitational body not only uses the electromagnetic field and interactions. For example, the range of both has acquired, through evolution, resistance to interactions is infinitive, as opposed to the two some of its forms, but also has become a source interactions that are rightly called “nuclear,” the of the electromagnetic field – and in a fairly range of which is limited in practice to the nearest wide frequency range. Furthermore, for over 100 surroundings
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