Digital Enhanced Cordless Telecommunications Research Articles

DECT-2020 New Radio: The Next Step toward 5G Massive Machine-Type Communications

Massive machine type communications (mMTC) is one of the cornerstone services that must be supported by 5G systems. 3GPP has already introduced LTE-M and NB-IoT, referred to as cellular IoT (CIoT), in 3GPP Releases 13, 14, and 15, and submitted these technologies as part of 3GPP's IMT-2020 technology submission to ITU-R. Even though NB-IoT and LTE-M have been shown to satisfy 5G mMTC requirements, it is expected that these CIoT solutions will not address all aspects of IoT and ongoing digitalization, including the support for direct communication between “things” with flexible deployments, different business models, as well as support for even higher node densities and enhanced coverage. In this article, we first describe the Digital Enhanced Cordless Tele-communications (DECT) DECT-2020 standard recently published by ETSI for mMTC communications. We then evaluate its performance and compare it to the existing low-power wide area network solutions, showing that it outperforms those in terms of supported density of nodes while keeping delay and loss guarantees at the required level.

Improved team communication in endoscopic procedures by digital enhanced telecommunication during the COVID-19 pandemic

Background and study aims Unbiased communication is crucial for excellent teamwork in high-quality endoscopy. Personal protective equipment (PPE) (FFP-masks and face-shields) worn by endoscopists that are ubiquitous in the current COVID-19 pandemic strikingly impair communication. Digital enhancement approaches to maintain team communication, especially during complex endoscopic procedures, are urgently warranted. Materials and methods A prospective, two-armed interventional study was performed at an endoscopy unit at a tertiary center in Germany. Two hundred and three endoscopic procedures with PPE se according to pandemic risk level were randomly assigned (1:1) to a group performed by an endoscopy team equipped with digital enhanced cordless telecommunication (DECT) or one without digital-enhanced communication. The primary outcome was the team-reported number of communication-associated events (CAEs) defined as misunderstandings that impaired workflow during endoscopic examination. Secondary outcomes included perceived voice and headphone quality and overall comfort with DECT during endoscopic work. Results The use of DECT was associated with a significant reduction in communication-associated events in endoscopic procedures and overall, was perceived positively. Conclusions Digital enhancement of communication is a promising and easy-to- establish tool for improving team communication quality in endoscopy.

Prototype wireless network for internet of things based on DECT standard

This paper presents a software prototype of a wireless network for the Internet of Things (IoT) based on the DECT (Digital Enhanced Cordless Telecommunication) standard. It proposes an architecture for encapsulating commands from the most common IoT protocol, MQTT (Message Queuing Telemetry Transport), into SIP (Session Initiation Protocol) packets. A module is created to embed MQTT-SN (MQTT for Sensor Networks) packets into SIP packets. The module is developed in Go language using the built-in "net" library. Delivery of MQTT-SN packets to IoT devices is carried out using the SIP protocol. Source codes and instructions for installing the gateway can be found at https://github.com/iSinyavsky/mqtt-sn-sip-gateway.

Estimated all-day and evening whole-brain radiofrequency electromagnetic fields doses, and sleep in preadolescents

ObjectiveTo investigate the association of estimated all-day and evening whole-brain radiofrequency electromagnetic field (RF-EMF) doses with sleep disturbances and objective sleep measures in preadolescents. MethodsWe included preadolescents aged 9–12 years from two population-based birth cohorts, the Dutch Generation R Study (n = 974) and the Spanish INfancia y Medio Ambiente Project (n = 868). All-day and evening overall whole-brain RF-EMF doses (mJ/kg/day) were estimated for several RF-EMF sources including mobile and Digital Enhanced Cordless Telecommunications (DECT) phone calls (named phone calls), other mobile phone uses, tablet use, laptop use (named screen activities), and far-field sources. We also estimated all-day and evening whole-brain RF-EMF doses in these three groups separately (i.e. phone calls, screen activities, and far-field). The Sleep Disturbance Scale for Children was completed by mothers to assess sleep disturbances. Wrist accelerometers together with sleep diaries were used to measure sleep characteristics objectively for 7 consecutive days. ResultsAll-day whole-brain RF-EMF doses were not associated with self-reported sleep disturbances and objective sleep measures. Regarding evening doses, preadolescents with high evening whole-brain RF-EMF dose from phone calls had a shorter total sleep time compared to preadolescents with zero evening whole-brain RF-EMF dose from phone calls [-11.9 min (95%CI -21.2; −2.5)]. ConclusionsOur findings suggest the evening as a potentially relevant window of RF-EMF exposure for sleep. However, we cannot exclude that observed associations are due to the activities or reasons motivating the phone calls rather than the RF-EMF exposure itself or due to chance finding.

Association between estimated whole-brain radiofrequency electromagnetic fields dose and cognitive function in preadolescents and adolescents.

To investigate the association between estimated whole-brain radiofrequency electromagnetic fields (RF-EMF) dose, using an improved integrated RF-EMF exposure model, and cognitive function in preadolescents and adolescents. Cross-sectional analysis in preadolescents aged 9-11 years and adolescents aged 17-18 years from the Dutch Amsterdam Born Children and their Development Study (n=1664 preadolescents) and the Spanish INfancia y Medio Ambiente Project (n=1288 preadolescents and n=261 adolescents), two population-based birth cohort studies. Overall whole-brain RF-EMF doses (mJ/kg/day) were estimated for several RF-EMF sources together including mobile and Digital Enhanced Cordless Telecommunications phone calls (named phone calls), other mobile phone uses than calling, tablet use, laptop use (named screen activities), and far-field sources. We also estimated whole-brain RF-EMF doses in these three groups separately (i.e. phone calls, screen activities, and far-field) that lead to different patterns of RF-EMF exposure. We assessed non-verbal intelligence in the Dutch and Spanish preadolescents, information processing speed, attentional function, and cognitive flexibility in the Spanish preadolescents, and working memory and semantic fluency in the Spanish preadolescents and adolescents using validated neurocognitive tests. Estimated overall whole-brain RF-EMF dose was 90.1mJ/kg/day (interquartile range (IQR) 42.7; 164.0) in the Dutch and Spanish preadolescents and 105.1mJ/kg/day (IQR 51.0; 295.7) in the Spanish adolescents. Higher overall estimated whole-brain RF-EMF doses from all RF-EMF sources together and from phone calls were associated with lower non-verbal intelligence score in the Dutch and Spanish preadolescents (-0.10 points, 95% CI -0.19; -0.02 per 100mJ/kg/day increase in each exposure). However, none of the whole-brain RF-EMF doses was related to any other cognitive function outcome in the Spanish preadolescents or adolescents. Our results suggest that higher brain exposure to RF-EMF is related to lower non-verbal intelligence but not to other cognitive function outcomes. Given the cross-sectional nature of the study, the small effect sizes, and the unknown biological mechanisms, we cannot discard that our resultsare due to chance finding or reverse causality. Longitudinal studies on RF-EMF brain exposure and cognitive function are needed.

Estimated whole-brain and lobe-specific radiofrequency electromagnetic fields doses and brain volumes in preadolescents

ObjectiveTo assess the association between estimated whole-brain and lobe-specific radiofrequency electromagnetic fields (RF-EMF) doses, using an improved integrated RF-EMF exposure model, and brain volumes in preadolescents at 9–12 years old. MethodsCross-sectional analysis in preadolescents aged 9–12 years from the Generation R Study, a population-based birth cohort set up in Rotterdam, The Netherlands (n = 2592). An integrated exposure model was used to estimate whole-brain and lobe-specific RF-EMF doses (mJ/kg/day) from different RF-EMF sources including mobile and Digital Enhanced Cordless Telecommunications (DECT) phone calls, other mobile phone uses than calling, tablet use, laptop use, and far-field sources. Whole-brain and lobe-specific RF-EMF doses were estimated for all RF-EMF sources together (i.e. overall) and for three groups of RF-EMF sources that lead to a different pattern of RF-EMF exposure. Information on brain volumes was extracted from magnetic resonance imaging scans. ResultsEstimated overall whole-brain RF-EMF dose was 84.3 mJ/kg/day. The highest overall lobe-specific dose was estimated in the temporal lobe (307.1 mJ/kg/day). Whole-brain and lobe-specific RF-EMF doses from all RF-EMF sources together, from mobile and DECT phone calls, and from far-field sources were not associated with global, cortical, or subcortical brain volumes. However, a higher whole-brain RF-EMF dose from mobile phone use for internet browsing, e-mailing, and text messaging, tablet use, and laptop use while wirelessly connected to the internet was associated with a smaller caudate volume. ConclusionsOur results suggest that estimated whole-brain and lobe-specific RF-EMF doses were not related to brain volumes in preadolescents at 9–12 years old. Screen activities with mobile communication devices while wirelessly connected to the internet lead to low RF-EMF dose to the brain and our observed association may thus rather reflect effects of social or individual factors related to these specific uses of mobile communication devices. However, we cannot discard residual confounding, chance finding, or reverse causality. Further studies on mobile communication devices and their potential negative associations with brain development are warranted, regardless whether associations are due to RF-EMF exposure or to other factors related to their use.

A simple method to design a tri-bandpass filter using open-loop uniform impedance resonators

ABSTRACTThe paper presents a simple method to design a tri-band bandpass filter (BPF) using only two pairs of open-loop uniform impedance resonators (OLUIRs). The three passbands can be designed independently by selecting the lengths of two pairs of the OLUIRs. The design procedure is described in this paper. A tri-bandpass filter example is designed at 1.93, 2.6 and 3.9 GHz that can be applied to digital enhanced cordless telecommunications (DECT) and worldwide interoperability for microwave access (WiMAX). By means of the cross-coupling effect with different coupling paths, several transmission zeros appear near the passbands, thus enhancing the selectivity of the passbands. The measured results of the fabricated tri-BPF match the simulated results and confirm the design concept.

Environmental radiofrequency electromagnetic field levels in a department of pediatrics

Preterm neonates constitute a vulnerable population that is highly sensitive to its environment. Given the increased use of wireless communication devices (mobile and digital enhanced cordless telecommunications, WiFi networks, etc.), neonates hospitalized in a department of pediatrics are potentially exposed to radiofrequency electromagnetic fields (RF-EMF). Strikingly, data on RF-EMF levels in pediatric units have not previously been published.The objective of the present study was thus to quantify the RF-EMF levels in a 34-bed tertiary department of pediatrics with a neonatal critical care unit (NCCU) and a neonatal intensive care unit (NICU). To this end, we used triaxle antenna dosimeters to map the RF-EMF levels in the environment and to measure spot emissions from medical devices. In a first set of experiments, RF-EMF levels at 144 points in the staff area and in the children's rooms in the NCCU and NICU were evaluated over a 24-h period. In a second set of measurements performed in a Faraday chamber, we measured the RF-EMF levels emitted by the medical devices to which neonates are potentially exposed in the department of pediatrics.The RF-EMF levels were significantly higher in the NCCU than in the NICU (p < 0.05). Although the two units did not differ significantly with regard to the average maximum values, the single greatest value recorded in the NCCU (6 V/m GSM + UMTS 900 (UL) frequency band, in the staff area) was more than twice that recorded in the NICU (3.70 V/m in the UMTS 2100 (UL) frequency band, in the children's rooms). The NCCU and NICU did not differ significantly with regard to the time during which the RF-EMF level at each measurement point was more than two standard deviations above its mean. The RF-EMF level was significantly higher during the day than during the night (p < 0.001). The various medical devices used in the NICU did not emit detectable amounts of RF.Overall, RF-EMF levels in the NCCU and NICU were very low. It is probable that the RF-EMFs measured here were primarily generated by the parents' and staff members' activities, rather than by medical devices. However, a combination of low-level, chronic exposure with transient, elevated peak values in a vulnerable population of preterm neonates may be of particular concern. In a department of pediatrics, decreasing preterm neonates’ exposure to RF-EMFs should primarily involve a limitation on the use of wireless communication devices by staff members and parents.

An Improvement of the CS Attack to DSC Cipher

Abstract The DECT standard cipher (DSC) is a 64-bit stream cipher, which was used in the digital enhanced cordless telecommunications (DECT) standard to protect the privacy of users. The Coisel–Sanchez (CS) attack proposed by Coisel and Sanchez in CHES 2015 is the most effective cryptanalysis against the DSC cipher up to now. Based on the CS attack, we present an improved attack in which an information collection method with unknown memory is used to improve the utilization of information and the message classification technique is adopted to reduce the computation time of evaluation indexes. Meanwhile, we present an improved pre-sieving technique to avoid the computation of evaluation indexes of a large number of incorrect candidates. Our known plaintext attack requires only 2 min of communication compared to 3 min for the CS attack. By analyzing 213 keystreams, our approach is able to increase the success probability of retrieving secret key from 55–89%. As far as we know, the attack we present in this paper is the most effective one among the existing attacks to the DSC cipher.

Personal exposure to radio-frequency electromagnetic fields in Europe: Is there a generation gap?

BackgroundExposure to radiofrequency electromagnetic fields (RF-EMF) from mobile communication technologies is changing rapidly. To characterize sources and associated variability, we studied the differences and correlations in exposure patterns between children aged 8 to 18 and their parents, over the course of the day, by age, by activity pattern, and for different metrics of exposure. MethodsUsing portable RF-EMF measurement devices, we collected simultaneous real-time personal measurements of RF-EMF over 24 to 72 h in 294 parent-child pairs from Denmark, the Netherlands, Slovenia, Switzerland, and Spain. The devices measured the power flux density (mW/m2) in 16 different frequency bands every 4 s, and activity diary Apps kept by the participants were used to collect time-activity information in real-time. We analyzed their exposures by activity, for the different source constituents of exposure: downlink (radiation emitted from mobile phone base stations), uplink (transmission from phone to base station), broadcast, DECT (digital enhanced cordless telecommunications) and Wi-Fi. We looked at the correlations between parents and children overall, during day (06:00–22.00) and night (22:00–06:00) and while spending time at home. ResultsThe mean of time-weighted average personal exposures was 0.16 mW/m2 for children and 0.15 mW/m2 for parents, on average predominantly originating from downlink sources (47% for children and 45% for parents), followed by uplink (18% and 27% respectively) and broadcast (25% and 19%). On average, exposure for downlink and uplink were highest during the day, and for Wi-Fi and DECT during the evening. Exposure during activities where most of the time is spent (home, school and work) was relatively low whereas exposure during travel and outside activities was higher. Exposure to uplink increased with age among young people, while DECT decreased slightly. Exposure to downlink, broadcast, and Wi-Fi showed no obvious trend with age. We found that exposure to total RF-EMF is correlated among children and their parents (Rspearman = 0.45), especially while at home (0.62) and during the night (0.60). Correlations were higher for environmental sources such as downlink (0.57) and broadcast (0.62) than for usage-related exposures such as uplink (0.29). ConclusionThe generation gap between children and their parents is mostly evident in uplink exposure, due to more and longer uplink and cordless phone calls among parents, and their tendency to spend slightly more time in activities with higher environmental RF-EMF exposure, such as travel. Despite these differences in personal behavior, exposure to RF-EMF is moderately correlated between children and their parents, especially exposures resulting from environmental RF-EMF sources.

Spatial and temporal variability of personal environmental exposure to radio frequency electromagnetic fields in children in Europe

BackgroundExposure to radiofrequency electromagnetic fields (RF-EMF) has rapidly increased and little is known about exposure levels in children. This study describes personal RF-EMF environmental exposure levels from handheld devices and fixed site transmitters in European children, the determinants of this, and the day-to-day and year-to-year repeatability of these exposure levels. MethodsPersonal environmental RF-EMF exposure (μW/m2, power flux density) was measured in 529 children (ages 8–18 years) in Denmark, the Netherlands, Slovenia, Switzerland, and Spain using personal portable exposure meters for a period of up to three days between 2014 and 2016, and repeated in a subsample of 28 children one year later. The meters captured 16 frequency bands every 4 s and incorporated a GPS. Activity diaries and questionnaires were used to collect children's location, use of handheld devices, and presence of indoor RF-EMF sources. Six general frequency bands were defined: total, digital enhanced cordless telecommunications (DECT), television and radio antennas (broadcast), mobile phones (uplink), mobile phone base stations (downlink), and Wireless Fidelity (WiFi). We used adjusted mixed effects models with region random effects to estimate associations of handheld device use habits and indoor RF-EMF sources with personal RF-EMF exposure. Day-to-day and year-to-year repeatability of personal RF-EMF exposure were calculated through intraclass correlations (ICC). ResultsMedian total personal RF-EMF exposure was 75.5 μW/m2. Downlink was the largest contributor to total exposure (median: 27.2 μW/m2) followed by broadcast (9.9 μW/m2). Exposure from uplink (4.7 μW/m2) was lower. WiFi and DECT contributed very little to exposure levels. Exposure was higher during day (94.2 μW/m2) than night (23.0 μW/m2), and slightly higher during weekends than weekdays, although varying across regions. Median exposures were highest while children were outside (157.0 μW/m2) or traveling (171.3 μW/m2), and much lower at home (33.0 μW/m2) or in school (35.1 μW/m2). Children living in urban environments had higher exposure than children in rural environments. Older children and users of mobile phones had higher uplink exposure but not total exposure, compared to younger children and those that did not use mobile phones. Day-to-day repeatability was moderate to high for most of the general frequency bands (ICCs between 0.43 and 0.85), as well as for total, broadcast, and downlink for the year-to-year repeatability (ICCs between 0.49 and 0.80) in a small subsample. ConclusionThe largest contributors to total personal environmental RF-EMF exposure were downlink and broadcast, and these exposures showed high repeatability. Urbanicity was the most important determinant of total exposure and mobile phone use was the most important determinant of uplink exposure. It is important to continue evaluating RF-EMF exposure in children as device use habits, exposure levels, and main contributing sources may change.

Influence of Telecommunication Modality, Internet Transmission Quality, and Accessories on Speech Perception in Cochlear Implant Users.

BackgroundTelecommunication is limited or even impossible for more than one-thirds of all cochlear implant (CI) users.ObjectiveWe sought therefore to study the impact of voice quality on speech perception with voice over Internet protocol (VoIP) under real and adverse network conditions.MethodsTelephone speech perception was assessed in 19 CI users (15-69 years, average 42 years), using the German HSM (Hochmair-Schulz-Moser) sentence test comparing Skype and conventional telephone (public switched telephone networks, PSTN) transmission using a personal computer (PC) and a digital enhanced cordless telecommunications (DECT) telephone dual device. Five different Internet transmission quality modes and four accessories (PC speakers, headphones, 3.5 mm jack audio cable, and induction loop) were compared. As a secondary outcome, the subjective perceived voice quality was assessed using the mean opinion score (MOS).ResultsSpeech telephone perception was significantly better (median 91.6%, P<.001) with Skype compared with PSTN (median 42.5%) under optimal conditions. Skype calls under adverse network conditions (data packet loss > 15%) were not superior to conventional telephony. In addition, there were no significant differences between the tested accessories (P>.05) using a PC. Coupling a Skype DECT phone device with an audio cable to the CI, however, resulted in higher speech perception (median 65%) and subjective MOS scores (3.2) than using PSTN (median 7.5%, P<.001).ConclusionsSkype calls significantly improve speech perception for CI users compared with conventional telephony under real network conditions. Listening accessories do not further improve listening experience. Current Skype DECT telephone devices do not fully offer technical advantages in voice quality.

Applying Broadband Dielectric Spectroscopy (BDS) for the Biophysical Characterization of Mammalian Tissues under a Variety of Cellular Stresses.

The dielectric properties of biological tissues can contribute non-invasively to a better characterization and understanding of the structural properties and physiology of living organisms. The question we asked, is whether these induced changes are effected by an endogenous or exogenous cellular stress, and can they be detected non-invasively in the form of a dielectric response, e.g., an AC conductivity switch in the broadband frequency spectrum. This study constitutes the first methodological approach for the detection of environmental stress-induced damage in mammalian tissues by the means of broadband dielectric spectroscopy (BDS) at the frequencies of 1–106 Hz. Firstly, we used non-ionizing (NIR) and ionizing radiation (IR) as a typical environmental stress. Specifically, rats were exposed to either digital enhanced cordless telecommunication (DECT) radio frequency electromagnetic radiation or to γ-radiation, respectively. The other type of stress, characterized usually by high genomic instability, was the pathophysiological state of human cancer (lung and prostate). Analyzing the results of isothermal dielectric measurements provided information on the tissues’ water fraction. In most cases, our methodology proved sufficient in detecting structural changes, especially in the case of IR and malignancy. Useful specific dielectric response patterns are detected and correlated with each type of stress. Our results point towards the development of a dielectric-based methodology for better understanding and, in a relatively invasive way, the biological and structural changes effected by radiation and developing lung or prostate cancer often associated with genomic instability.

ELF exposure from mobile and cordless phones for the epidemiological MOBI-Kids study

This paper describes measurements and computational modelling carried out in the MOBI-Kids case-control study to assess the extremely low frequency (ELF) exposure of the brain from use of mobile and cordless phones. Four different communication systems were investigated: Global System for Mobile (GSM), Universal Mobile Telecommunications System (UMTS), Digital Enhanced Cordless Telecommunications (DECT) and Wi-Fi Voice over Internet Protocol (VoIP). The magnetic fields produced by the phones during transmission were measured under controlled laboratory conditions, and an equivalent loop was fitted to the data to produce three-dimensional extrapolations of the field. Computational modelling was then used to calculate the induced current density and electric field strength in the brain resulting from exposure to these magnetic fields. Human voxel phantoms of four different ages were used: 8, 11, 14 and adult. The results indicate that the current densities induced in the brain during DECT calls are likely to be an order of magnitude lower than those generated during GSM calls but over twice that during UMTS calls. The average current density during Wi-Fi VoIP calls was found to be lower than for UMTS by 30%, but the variability across the samples investigated was high. Spectral contributions were important to consider in relation to current density, particularly for DECT phones. This study suggests that the spatial distribution of the ELF induced current densities in brain tissues is determined by the physical characteristics of the phone (in particular battery position) while the amplitude is mainly dependent on communication system, thus providing a feasible basis for assessing ELF exposure in the epidemiological study. The number of phantoms was not large enough to provide definitive evidence of an increase of induced current density with age, but the data that are available suggest that, if present, the effect is likely to be very small.

Electromagnetic system for detection and localization of miners caught in mine accidents

Abstract. The profession of a miner is one of the most dangerous in the world. Among the main causes of fatalities in underground coal mines are the delayed alert of the accident and the lack of information regarding the actual location of the miners after the accident. In an emergency situation (failure or destruction of underground infrastructure), personnel search behind and beneath blockage needs to be performed urgently. However, none of the standard technologies – radio-frequency identification (RFID), Digital Enhanced Cordless Telecommunications (DECT), Wi-Fi, emitting cables, which use the stationary technical devices in mines – provide information about the miners location with the necessary precision. The only technology that is able to provide guaranteed delivery of messages to mine personnel, regardless of their location and under any destruction in the mine, is low-frequency radio technology, which is able to operate through the thickness of rocks even if they are wet. The proposed new system for miner localization is based on solving the inverse problem of determining the magnetic field source coordinates using the data of magnetic field measurements. This approach is based on the measurement of the magnetic field radiated by the miner's responder beacon using two fixed and spaced three-component magnetic field receivers and the inverse problem solution. As a result, a working model of the system for miner's beacon search and localization (MILES – MIner's Location Emergency System) was developed and successfully tested. This paper presents the most important aspects of this development and the results of experimental tests.

A Study Regarding Failure Detection for String Monitoring Systems in Photovoltaics. Field Trial at the F Onomichi Photovoltaic Power Plant

SUMMARYSolar power business has been expanding rapidly in Japan since the new feed‐in tariff began in July 2012. Generally, monitoring for failure detection and total electric generating capacity is performed by the power conditioning system (PCS) in a large‐scale photovoltaic (PV) power plant. Although PCS monitoring can detect its own failure or a reduction in power generation amount, it is difficult to monitor in a PV string/panel. In this paper, a new failure detection method effective for detection in PV strings, by collecting the current value of each string measured at each terminal and analyzing these data, is proposed. The data collection is performed utilizing the Digital Enhanced Cordless Telecommunications wireless communication method, realizing easy installation in both existing and new PV power plants. Finally, the effectiveness of this proposed method is shown in real‐facility demonstration experiments using the F Onomichi PV power plant.

Improved cryptanalysis of the DECT standard cipher

The DECT Standard Cipher (DSC) is a 64-bit key stream cipher used in the Digital Enhanced Cordless Telecommunications (DECT) standard to protect the confidentiality of the communications. In this paper we present an improved cryptanalysis approach which is more effective than the Nohl-Tews-Weinmann (NTW) attack and requires four times less plaintext material. Under the best conditions, our known plaintext attack requires only 3 min of communication compared to 10 min for the NTW attack. Our approach is able to quickly recover the secret key with a success rate of more than 50 % by analysing \(2^{13}\) keystreams and performing an exhaustive search over \(2^{31}\) keys. Additionally, the attack was successfully conducted against real intercepted DECT traffic where the plaintext was only 90 % accurate. To the best of our knowledge, the approach we present in this paper is the most effective cryptanalysis published so far against the DSC cipher.

Electromagnetic fields in the vicinity of DECT cordless telephones and mobile phones

Mobile telephones belong to the most frequently used personal devices. In their surroundings they produce the electromagnetic field (EMF), in which exposure range there are not only users but also nearby bystanders. The aim of the investigations and EMF measurements in the vicinity of phones was to identify the electric field levels with regard to various working modes. Twelve sets of DECT (digital enhanced cordless telecommunications) cordless phones (12 base units and 15 handsets), 21 mobile telephones produced by different manufactures, and 16 smartphones in various applications, (including multimedia) in the conditions of daily use in living rooms were measured. Measurements were taken using the point method in predetermined distances of 0.05-1 m from the devices without the presence of users. In the vicinity of DECT cordless phone handsets, electric field strength ranged from 0.26 to 2.30 V/m in the distance of 0.05 m - 0.18-0.26 V/m (1 m). In surroundings of DECT cordless telephones base units the values of EMF were from 1.78-5.44 V/m (0.05 m) to 0.19- 0.41 V/m (1 m). In the vicinity of mobile phones working in GSM mode with voice transmission, the electric field strength ranged from 2.34-9.14 V/m (0.05 m) to 0.18-0.47 V/m (1 m) while in the vicinity of mobile phones working in WCDMA (Wideband Code Division Multiple Access) mode the electric field strength ranged from 0.22-1.83 V/m (0.05 m) to 0.18-0.20 V/m (1 m). The mean values of the electric field strength for each group of devices, mobile phones and DECT wireless phones sets do not exceed the reference value of 7 V/m, adopted as the limit for general public exposure.

Effect of Magnetic Field From Mobile Phone on Brain

Human exposure to electromagnetic field (EMF) comes from many different sources and occurs in various situations in everyday life. Man-made static fields are mainly found in occupational settings, such as close to magnetic resonance imaging (MRI) scanners, although DC high-voltage overhead transmission lines are being constructed, which are expected to expose larger parts of the population to static electric and magnetic fields.Today, for power regulation most modern electrical equipment uses electronics instead of transformers. Examples include the switched power supplies to laptops, drilling tools, chargers of mobile phones and similar devices. As a consequence, the frequency content of the daily magnetic field exposure has changed mainly by adding odd harmonics (150 Hz, 250 Hz, 750 Hz, etc.). In particular, the third harmonic (150 Hz) has become another dominating frequency in our environment.In particular for brain tissues, the mobile phone used at the ear remains the main source of exposure. However, since the first generation of mobile telephony, the technology aimed at reducing the emitted power of mobile handsets. In particular, for Global System for Mobile communication (GSM) already the introduction of dynamic power control reduced the average output power to about 50% of its rated value during calls, whereas the use of discontinuous transmission during voice calls gave a further 30% reduction in average emitted power. Adaptive power control became faster and more effective in the third-generation (3G) of mobile telephony systems leading to a further reduction (by about two orders of magnitude) in the specific absorption Specific energy Absorption Rate (SAR) compared to GSM phones. In addition, hands-free kits reduce the energy absorbed by the head drastically. Digital Enhanced Cordless Telecommunications (DECT) phones are another source of everyday exposure.

Public Exposure from Indoor Radiofrequency Radiation in the City of Hebron, West Bank-Palestine.

This work presents the results of measured indoor exposure levels to radiofrequency (RF) radiation emitting sources in one of the major cities in the West Bank-the city of Hebron. Investigated RF emitters include FM, TV broadcasting stations, mobile telephony base stations, cordless phones [Digital Enhanced Cordless Telecommunications (DECT)], and wireless local area networks (WLAN). Measurements of power density were conducted in 343 locations representing different site categories in the city. The maximum total power density found at any location was about 2.3 × 10 W m with a corresponding exposure quotient of about 0.01. This value is well below unity, indicating compliance with the guidelines of the International Commission on Non-ionizing Radiation Protection (ICNIRP). The average total exposure from all RF sources was 0.08 × 10 W m. The relative contributions from different sources to the total exposure in terms of exposure quotient were evaluated and found to be 46% from FM radio, 26% from GSM900, 15% from DECT phones, 9% from WLAN, 3% from unknown sources, and 1% from TV broadcasting. RF sources located outdoors contribute about 73% to the population exposure indoors.