Telecommunications networks use modulation techniques to transmit information wirelessly between mobile devices and cell towers. These modulation strategies have evolved over time to meet the increasing demand for faster and more reliable communication across different generations of cellular networks.

The first generation (1G) of wireless technology was introduced in the 1980s, and used analog frequency modulation for voice calls.

2G networks became commercially available in 1992 and used three common multiple access technologies for accommodating multiple simultaneous users:

•Frequency Division Multiple Access (FDMA)

•Division Multiple Access (TDMA)

•Code Division Multiple Access (CDMA)

Third and fourth generations of network technologies were introduced in 1998 (3G), 2006 (4G), and in 2011, 4G-Long Term Evolution (LTE).

All 3G systems utilize CDMA/WCDMA technology.

Reference: NTP Technical Report on the Toxicology and Carcinogenesis Studies in Sprague Dawley (Hsd:Sprague Dawley^® SD^®) Rats Exposed to Whole-body Radio Frequency Radiation at a Frequency (900 Mhz) and Modulations (GSM and CDMA) Used by Cell Phones: Technical Report 595 [Internet]. https://www.ncbi.nlm.nih.gov/books/NBK561723/

Orthogonal Frequency Division Multiplexing (OFDM) is a widely used modulation scheme in 4G communication systems such as Long-Term Evolution (LTE) and LTE Advanced, and it has also become the standard modulation format for 5G New Radio. Quadrature Amplitude Modulation (QAM) is a modern digital modulation technique used in 4G, 5G and Wi-Fi6 networks. 

Many new modulation and multiple access (MA) schemes are being developed for 5G to meet the changing demands of large-scale, heterogeneous traffic and users.

Energy efficiency improvements are imperative for 5G networks, and optimum modulation techniques can be employed to reach the capacity increase in 5G. Satellite communications also employ complex modulation schemes to improve spectral efficiency and minimize nonlinear amplification in the RF power amplifier. *References at the bottom of the post.

Pulse modulation involves transmitting a series of pulses to convey information. Some studies have suggested that this pulsing effect by radiofrequency radiation could have negative health effects on health by interfering with biological processes. 

Does ICNIRP (The International Commission on Non-Ionizing Radiation Protection) consider modulation in its research and guidelines on non-ionizing radiation?

According to ICNIRP:

•Its guidelines account for all RF-EMF transmission protocols and modulation schemes, and so in terms of biological or health effects, these factors are not new.  https://www.icnirp.org/cms/upload/publications/ICNIRPNoteMay2021.pdf

•ICNIRP considers the potential for different types of radiofrequency EMF exposure to adversely affect health, including sinusoidal (e.g., continuous wave) and non-sinusoidal (e.g., pulsed) EMFs, and both acute and chronic exposures.

•ICNIRP considers all potential adverse health effects (including non-thermal effects) and sets restrictions to ensure that none occur, regardless of the mechanism of interaction between the exposure and the body. The lowest exposure levels that can cause adverse health effects are due to thermal mechanisms, and so restrictions have been set based on the thermal effects, as these will protect against any other effects that could occur at higher exposure levels.

https://www.gsma.com/publicpolicy/wp-content/uploads/2021/10/GSMA_International_EMF_Exposure_Guideline_Oct21.pdf

Quote: “The observation of effects does not necessarily mean the finding of a hazard” Allan H. Frey

(Allan H. Frey was the first American to publish on the microwave auditory effect (MAE). Frey’s “Human auditory system response to modulated electromagnetic energy” appeared in the Journal of Applied Physiology in 1961).

IEEE Transactions on Microwave Theory and Technique Feb. 1971:

It was found that carrier frequency, and the relationship of the modulation to the function in its phases are critical in the effect of low power density rf energy on some functions of higher organisms (Frey, 1962, 1963, 19671 Frey and Siefert, 1968). 

For example, perception in the auditory system can be induced with carrier frequencies that penetrate the head but not those that do not penetrate the head, e.g. at 1 GHs but not at 10 GH. 

The auditory system perception cannot be produced unless the carrier is modulated.

The brainstem responses have not been observed with an unmodulated carrier. 

The isolated frog heart cannot be driven to arrhythmia if the rf pulse Impinges upon the heart at the P wave but it can be so driven if the rf pulse Impinges at the occurrence of the R wave.

It was found that there are critical body areas (Frey, 1967).

Peak rather than average power density was determined to be the more Important variable in the study of the effect of modulated low power density rf energy on biological functions (Frey, 1962, 1967).

Reference:  In Press. IEEE Transactions on Microwave Theory and Technique Feb. 1971. (Special issue on Biological Effects of Microwaves) https://apps.dtic.mil/sti/pdfs/AD0716044.pdf

2004: Biological Effects of Radiofrequency Fields: Does Modulation Matter?

Modulation has been a factor in public controversy related to health concerns. Following recommendations of the International EMF Project of the World Health Organization (WHO), a host of recent studies have examined possible biological effects of modulated RF energy similar to that produced by major wireless access technologies (such as GSM, TDMA, CDMA, TETRA), with separate evaluation of effects of each technology.

Coherent Oscillations of Biological Structures In the 1970s and 1980s the noted physicist Fröhlich (now deceased) proposed that RF fields can excite ‘‘coherent oscillations’’ in cell membranes and macromolecules (8). Hyland (9) has cited this work in support of his claims that biological systems can be influenced by the modulation characteristics of microwave signals from mobile phones. However, Adair (10) showed that the damping effects of water surrounding biological structures are far too strong to allow resonances to exist at RFs. Moreover, the energy that can be added to a biological structure by an RF field of reasonable strength is many orders of magnitude below the energy already present in the structure due to random thermal agitation. Supporters of the theory have not rebutted Adair’s objections, and other theories (e.g. 11) that propose sharp frequency effects in biological systems fail for similar reasons.

At least one expert group in the West has issued ‘‘precautionary’’ recommendations related to modulation. In May 2000, the Independent Expert Group on Mobile Phones (IEGMP) advised that ‘‘as a precautionary measure, amplitude modulation around 16 Hz should be avoided if possible, in future developments in signal coding’’ (15). This recommendation was also based on studies related to the calcium efflux effect.

Large body of studies from countries of the former Soviet Union reporting modulation-dependent effects, which have not been reviewed extensively by Western agencies. Notable among these are studies by the group led by Akoev in Pushchino (Russia) that reported modulation-dependent effects in a variety of in vivo and in vitro systems (19–24).

One thing is clear: If modulation is biologically significant (apart from a few special cases such as intense pulses), the entire rationale for RF exposure guidelines would need revision. Present evidence does not indicate that this is the case. While more data will be published that bear on this issue, they will not be coming in quickly and they are unlikely to be definitive. Given public concerns about the safety of wireless communications systems, the issue of ‘‘modulation’’ will not be easily settled.

Reference: Kenneth R. Foster and Michael H. Repacholi “Biological Effects of Radiofrequency Fields: Does Modulation Matter?,” Radiation Research 162(2), 219-225, (1 August 2004). https://doi.org/10.1667/RR3191

The effect of modulation Dr. Andrew Goldsworthy, Lecturer and Biological Safety Officer (retired) Imperial College London.

Living cell membranes are electrically non-linear and have a voltage across them of approximately 70mV. They are pierced by countless ion channels that behave like electrically biased Schottky diodes capable of rectifying and so demodulating any alternating signal (including microwave frequencies) with the demodulated low frequency components appearing between the inside and outside of the cell. This is what does most of the damage and here is why:

The cell membrane is mainly made of a lipid bilayer only about 10nM thick, with proteins such as ion channels “floating” in it. The membrane itself is negatively charged because it has outwardly directed negatively charged phosphate groups and is normally stabilised by divalent positive calcium and magnesium ions that cross-link them. But the demodulated cell-phone signal makes the negative membrane and its protective divalent ions move in opposite directions. This destabilizes the membrane and makes it more likely to perforate and collapse the voltage gradient across it. This, in turn, opens voltage-gated calcium ion channels in the membrane that let huge numbers of calcium ions into the cell down a massive 10,000:1 electrochemical gradient.

In nature, this increase in the internal calcium concentration is taken as an indicator to the cell that its membrane (and by implication, the whole cell) has been damaged and sets in train a series of repair mechanisms, which uses a great deal of metabolic energy. If it succeeds, the cell is repaired, if not, the cell dies, but either way a great deal of energy is used. This may in large part explain the chronic fatigue syndrome that was found in early mobile phone users (Yuppie flu) and is now much more widespread in the community due to our constant exposure to cordless phones, their base stations, WiFi and all the other wireless devices that current ICNIRP guidelines regard as safe.

Quote: “Many experiments do not include pulsing and modulation of the carrier signal.” Kostoff et al., 2020

Citation: Ronald N. Kostoff, Paul Heroux, Michael Aschner, Aristides Tsatsakis, Adverse health effects of 5G mobile networking technology under real-life conditions, Toxicology Letters, Volume 323, 2020, Pages 35-40, ISSN 0378-4274,https://doi.org/10.1016/j.toxlet.2020.01.020.

Brillouin precursors

There are concerns among some researchers and activists that the emergence of Brillouin precursors, which are sharp transients caused by the dispersion of broadband electromagnetic pulses in a dielectric, could have potential health impacts in the context of 5G technology. Some studies suggest that these precursors may increase the strength of electromagnetic radiation pulses and cause them to penetrate deeper into the human body than previously thought, potentially leading to health effects such as tissue damage and cancer. However, there is debate among experts over the validity of these concerns, with some arguing that the evidence is inconclusive or that the precursors may not pose a significant risk at the levels at which they are produced in 5G networks.

Are pulsing EMFs more bioactive than CW (continuous wave) EMFs?

•Comparing DNA damage induced by mobile telephony and other types of man-made electromagnetic fields Panagopoulos, 2019

It is important to note that except for the RF/microwave carrier frequency, Extremely Low Frequencies – ELFs (0–3000 Hz) are always present in all telecommunication EMFs in the form of pulsing and modulation.

The “ion forced-oscillation mechanism” for irregular gating of electro-sensitive ion channels on cell membranes which predicts that pulsing EMFs are more bioactive than CW EMFs of the same other parameters, and that the biological activity of any specific type of EMF is inversely proportional to its frequency and proportional to its intensity [[95], [96], [97]

https://pubmed.ncbi.nlm.nih.gov/31416578/]

•Human‑made electromagnetic fields: Ion forced‑oscillation and voltage‑gated ion channel dysfunction, oxidative stress and DNA damage (Review)

Panagopoulos et al., 2021

The ELF/ULF EMFs and even more the pulsing RF EMFs with ELF pulsations such as all WC EMFs, are predicted to be the most bioactive.

It has been claimed that the ELF components of complex RF-ELF EMFs of WC need to be ‘demodulated’ in order to be sensed by living organisms (232). ‘Demodulated’ or not, the fact is that the ELF components of modulated/pulsed WC signals can be directly sensed by both ELF meters/spectrum analyzers and living organisms (40,55).

Both DNA damage and alterations in protein synthesis, especially increased levels of stress proteins, are reported to be induced similarly by both ELF and pulsing RF EMFs (237,238). However, the effects of pulsing RF were attributed to the carrier frequency, and it was not considered that perhaps in both cases (ELF and pulsing RF) the ELF components might be responsible for the effects, as suggested now by the present study.

https://www.spandidos-publications.com/10.3892/ijo.2021.5272

The Europaem 2016 Table 3 suggests that the recommended radiation maximum levels of Wi-Fi are 1000 times less than for FM. Wi-Fi is pulsed, FM not.

As per ‘Biological Effects of Radiofrequency Fields: Does Modulation Matter?’ from 2004 (referenced earlier on in the post), given public concerns about the safety of wireless communications systems, the issue of ‘modulation’ will not easily be settled, even in 2023

*References

https://www.rfwireless-world.com/Terminology/What-is-modulation.html

https://www.thomasnet.com/articles/automation-electronics/what-is-modulation/

https://www.waveform.com/a/b/guides/modulation-coding-speeds

https://www.electronics-notes.com/articles/connectivity/4g-lte-long-term-evolution/ofdm-ofdma-scfdma-modulation.php

https://www.business.com/articles/what-is-802-11-ax-wi-fi/

https://ieeexplore.ieee.org/document/8085125

The post Wireless Communication Evolution: Modulation Techniques and Health Concerns with Pulse Modulation appeared first on EMFSA.

ABSTRACT

This is a review of studies on the neurological effects of static/extremely-low frequency (ELF) electromagnetic fields (EMF). The review is mainly on research carried out in the last two decades. There are studies that showed effects on various neurotransmitters, including NMDA, serotonin, dopamine, endogenous opioids, etc. Each of these transmitters plays different critical roles on behavior and brain functions. Studies on behavioral effects of static/ELF EMF bear out these connections. Static/ELF EMF-induced behavorial and pathological effects, such as locomotor activity, memory and learning deficits, and neurological diseases (Alzheimer’s, Parkinson’s disease, Huntinton’s diseases and atropical lateral scleroses, etc.) are discussed. Static/ELF EMF exposure has also been shown to have beneficial effects on functional deficits and progression of some neurological diseases. These fields provide a non-invasive treatment or treatment-adjuvant for these detrimental neurological conditions. Results suggest that free radicals, both reactive oxygen species and reactive nitric species could be involved. Depending on the conditions of exposure, either harmful or beneficial effects could result. It is important to carry out further investigation to identify these conditions. However, Caution should be taken to extrapolate the experimental data to human exposure, since higher field intensites than environmental levels were used in most laboratory research.

The post Neurological effects of static and extremely-low frequency electromagnetic fields appeared first on EMFSA.

According to the authors there is no evidence of a causal association between wireless phone use and brain tumours. Because of likely biases a small increased risk cannot be ruled out.

https://www.sciencedirect.com/science/article/pii/S0160412021006942

The post Results from the international MOBI-Kids study published appeared first on EMFSA.

Abstract

Whether the use of mobile phones (MP) represents a health hazard is still under debate. As part of the attempts to resolve this uncertainty, there has been an extensive characterization of the electromagnetic fields MP emit and receive. While the radiofrequencies (RF) have been studied exhaustively, the static magnetic fields (SMF) have received much less attention, regardless of the fact there is a wealth of evidence demonstrating their biological effects. We performed 2D maps of the SMF at several distances from the screen of 5 MP (models between 2013 and 2018) using a tri-axis magnetometer. We built a mathematical model to fit our measurements, extrapolated them down to the phones’ screen, and calculated the SMF on the skin of a 3D head model, showing that exposure is in the µT to mT range. Our literature survey prompts the need of further research not only on the biological effects of SMF and their gradients, but also on their combination with extremely low frequency (ELF) and RF fields. The study of combined fields (SMF, ELF, and RF) as similar as possible to the ones that occur in reality should provide a more sensible assessment of potential risks.

https://www.nature.com/articles/s41598-021-98083-9

The post Mapping of static magnetic fields near the surface of mobile phones appeared first on EMFSA.

ABSTRACT

Our previous studies have shown that intermittent exposure to a 50-Hz, 100-µT sine wave magnetic field (MF) promotes human NB69 cell proliferation, mediated by activation of the epidermal growth factor receptor (EGFR) and pathways MAPK-ERK1/2 and p38; being the effects on proliferation and p38 activation blocked by the chelator N-acetylcysteine. The present work investigates the MF effects on free radical (FR) production, and the potential involvement of NADPH oxidase, the main source of reactive oxygen species (ROS), in the MF-induced activation of MAPK pathways. To this end, the field effects on MAPK-ERK1/2, -p38 and -JNK activation in the presence or absence of the NADPH oxidase inhibitor, diphenyleneiodonium chloride (DPI), as well as the expression of the p67phox subunit, were analyzed. The results revealed that field exposure increases FR production and induces early, transient expression of the cytosolic component of the NADPH oxidase, p67phox. Also, the MF-induced activation of the MAPK-JNK pathway, but not that of -ERK1/2 or -p38 pathways, was prevented in the presence of the DPI, which has been shown to significantly reduce p67phox expression. These data, together with those from previous studies, identify various, FR-dependent or -independent mechanisms, involved in the MF-induced proliferative response mediated by MAPK signaling activation.

The post Role of NADPH oxidase in MAPK signaling activation by a 50 Hz magnetic field in human neuroblastoma cells appeared first on EMFSA.

The post Effect of Intermittent ELF MF on Umbilical Cord Blood Lymphocytes appeared first on EMFSA.

Abstract

Atmospheric electrical discharges during thunderstorms, and the related electromagnetic fields (EMFs)/waves called sferics, can be sensed by humans at long distances through a variety of symptoms, mainly headache, fatigue, etc. Up to today there is no explanation for this association. Sferics consist of partially polarized electromagnetic pulses with an oscillating carrier signal in the very low frequency (VLF) band and a pulse repetition frequency in the extremely low frequency (ELF) band. Their ELF intensity may reach ~ 5 mV/m at global ranges, and ~ 0.5 V/m at ~ 1000 km from the lightning. The health symptoms associated with sferics are also associated with antennas of mobile telephony base stations and handsets, which emit radio frequency (RF) radiation pulsed on ELF, and expose humans at similar or stronger electric field intensities with sferics.

According to the Ion Forced Oscillation mechanism, polarized ELF EMFs of intensities down to 0.1–1 mV/m are able to disrupt any living cell’s electrochemical balance and function by irregular gating of electro-sensitive ion channels on the cell membranes, and thus initiate a variety of health symptoms, while VLF EMFs need to be thousands of times stronger in order to be able to initiate health effects. We examine EMFs from sferics in terms of their bioactivity on the basis of this mechanism. We introduce the hypothesis that stronger atmospheric discharges may reasonably be considered to be ~ 70% along a straight line, and thus the associated EMFs (sferics) ~ 70% polarized. We find that sferics mainly in the ELF band have adequate intensity and polarization to cause biological/health effects. We provide explanation for the effects of sferics on human/animal health on the basis of this mechanism.

https://doi.org/10.1016/j.scitotenv.2017.05.089

The post On the biophysical mechanism of sensing atmospheric discharges by living organisms appeared first on EMFSA.

Abstract

Electromagnetic hypersensitivity (EHS), known in the past as “Microwave syndrome”, is a clinical syndrome characterized by the presence of a wide spectrum of non-specific multiple organ symptoms, typically including central nervous system symptoms, that occur following the patient’s acute or chronic exposure to electromagnetic fields in the environment or in occupational settings. Numerous studies have shown biological effects at the cellular level of electromagnetic fields (EMF) at magnetic (ELF) and radio-frequency (RF) frequencies in extremely low intensities. Many of the mechanisms described for Multiple Chemical Sensitivity (MCS) apply with modification to EHS. Repeated exposures result in sensitization and consequent enhancement of response. Many hypersensitive patients appear to have impaired detoxification systems that become overloaded by excessive oxidative stress. EMF can induce changes in calcium signaling cascades, significant activation of free radical processes and overproduction of reactive oxygen species (ROS) in living cells as well as altered neurological and cognitive functions and disruption of the blood-brain barrier. Magnetite crystals absorbed from combustion air pollution could have an important role in brain effects of EMF. Autonomic nervous system effects of EMF could also be expressed as symptoms in the cardiovascular system. Other common effects of EMF include effects on skin, microvasculature, immune and hematologic systems. It is concluded that the mechanisms underlying the symptoms of EHS are biologically plausible and that many organic physiologic responses occur following EMF exposure. Patients can have neurologic, neuro-hormonal and neuro-psychiatric symptoms following exposure to EMF as a consequence of neural damage and over-sensitized neural responses. More relevant diagnostic tests for EHS should be developed. Exposure limits should be lowered to safeguard against biologic effects of EMF. Spread of local and global wireless networks should be decreased, and safer wired networks should be used instead of wireless, to protect susceptible members of the public. Public places should be made accessible for electrohypersensitive individuals.

https://pubmed.ncbi.nlm.nih.gov/32289567/

The post Electromagnetic hypersensitivity (EHS, microwave syndrome) – Review of mechanisms appeared first on EMFSA.

Table 1. Data gaps in knowledge related to low frequency electric and magnetic fields and health.

https://www.icnirp.org/cms/upload/publications/ICNIRPlfgaps2020.pdf

https://pubmed.ncbi.nlm.nih.gov/32251081/

The post ICNIRP: GAPS IN KNOWLEDGE RELEVANT TO THE “GUIDELINES FOR LIMITING EXPOSURE TO TIME-VARYING ELECTRIC AND MAGNETIC FIELDS (1 HZ–100 KHZ)” appeared first on EMFSA.

Abstract

Since 2009, we built up a database which presently includes more than 2000 electrohypersensitivity (EHS) and/or multiple chemical sensitivity (MCS) self-reported cases. This database shows that EHS is associated in 30% of the cases with MCS, and that MCS precedes the occurrence of EHS in 37% of these EHS/MCS-associated cases. EHS and MCS can be characterized clinically by a similar symptomatic picture, and biologically by low-grade inflammation and an autoimmune response involving autoantibodies against O-myelin. Moreover, 80% of the patients with EHS present with one, two, or three detectable oxidative stress biomarkers in their peripheral blood, meaning that overall these patients present with a true objective somatic disorder. Moreover, by using ultrasonic cerebral tomosphygmography and transcranial Doppler ultrasonography, we showed that cases have a defect in the middle cerebral artery hemodynamics, and we localized a tissue pulsometric index deficiency in the capsulo-thalamic area of the temporal lobes, suggesting the involvement of the limbic system and the thalamus. Altogether, these data strongly suggest that EHS is a neurologic pathological disorder which can be diagnosed, treated, and prevented. Because EHS is becoming a new insidious worldwide plague involving millions of people, we ask the World Health Organization (WHO) to include EHS as a neurologic disorder in the international classification of diseases.

Full text

https://www.mdpi.com/1422-0067/21/6/1915/htm

Copyright; This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

Image source: https://www.mdpi.com/1422-0067/21/6/1915/htm

The post Electrohypersensitivity as a Newly Identified and Characterized Neurologic Pathological Disorder: How to Diagnose, Treat, and Prevent It appeared first on EMFSA.