A novel configuration of a dual-band bandpass filter (BPF) working as a harmonic attenuator is introduced and fabricated. The proposed filter operates at 3 GHz, for UHF and SHF applications, and 6.3 GHz, for wireless applications. The presented layout has a symmetric structure, which consists of coupled resonators. The designing of the proposed resonator is performed by introducing a new LC equivalent model of coupled lines. To verify the LC model of the coupled lines, the lumped elements are calculated. The introduced filter has a wide stopband up to 85 GHz with 28th harmonic suppression, for the first channel, and 13th harmonic suppression, for the second channel. The harmonics are attenuated using a novel structure. Also, the proposed BPF has a compact size of 0.056 λg2. Having several transmission zeros (TZs) that improve the performance of the presented BPF is another feature. The proposed dual-band BPF is fabricated and measured to verify the design method, where the measurement results confirm the simulations.

In this study, numerical dosimetry of a code division multiple access (CDMA)/global system of mobile, digital cellular service (DCS)/personal communications service (PCS) and third generation signal jammer working with three antennas is presented. Three anatomical full human body models of different ages and gender exposed to the signal jammer electromagnetic (EM) waves at 900, 1800 and 2100 MHz, simultaneously, are numerically modelled using a high‐resolution finite‐difference time‐domain gridding; solved by a full‐wave three‐dimensional EM simulation software on a high‐performance workstation machine. The average specific absorption rate (SAR) in the whole human body and the peak spatial SAR averaged over 1 g induced in the head and torso biological tissues were evaluated at different distances from the signal jammer above a ground consisting of concrete and soil layers. The maximum radiated power by the signal jammer at different distances against the human body was calculated for the safe exposure in compliance with the Institute of Electrical and Electronics Engineers (IEEE)/American National Standards Institute (ANSI)/Federal Communications Commission (FCC) standard limits.

A new technique of hiding a speech signal clip inside a digital color image is proposed in this paper to improve steganography security and loading capacity. The suggested technique of image steganography is achieved using both spatial and cepstral domains, where the Mel-frequency cepstral coefficients (MFCCs) are adopted, as very efficient features of the speech signal. The presented technique in this paper contributes to improving the image steganography features through two approaches. First is to support the hiding capacity by the usage of the extracted MFCCs features and pitches extracted from the speech signal and embed them inside the cover color image rather than directly hiding the whole samples of the digitized speech signal. Second is to improve the data security by hiding the secret data (MFCCs features) anywhere in the host image rather than directly using the least significant bits substitution of the cover image. At the recovering side, the proposed approach recovers these hidden features and using them to reconstruct the speech waveform again by inverting the steps of MFCCs extraction to recover an approximated vocal tract response and combine it with recovered pitch based excitation signal. The results show a peak signal to noise ratio of 52.4 dB of the stego-image, which reflect a very good quality and a reduction ratio of embedded data to about (6%–25%). In addition, the results show a speech reconstruction degree of about 94.24% correlation with the original speech signal.

The possible biological hazards due to the mobile phone electromagnetic (EM) field exposure are caused mainly by a temperature rise in tissue. Hence, the calculation of temperature in tissue may be more realistic than the calculation of specific absorption rate (SAR) due to the more direct relationship between temperature and safety. The heat transfer to human tissue due to a phone call is caused by a combined effect of conductive heat transfer caused by the basic non-microwave-related activity of the mobile phone and the absorption of the microwave. This paper investigates the role of heat transfer in living tissue due to thermal conduction. This is achieved using a thermal imaging camera to measure and map the skin temperature distribution over human head due to mobile phone EM emission. Two commercial mobile phone brands, that is, Apple iPhone 7 Plus and Huawei P20 Pro, are used at 1800 MHz cellular connection and approximate radiated power of 0.125 W to measure the skin temperature over human head at both, cheek and tilt position for 6 and 30 min calls. The results show that in spite of the direct proportion between the deposited SAR and temperature increase in human tissues, the heat transfer due to thermal conduction may not directly proportional to the SAR, where other factors may play important roles, for example, mobile phone chassis material, heated battery, antenna location inside the mobile phone, and mobile phone position in close proximity to head.Index Terms-Apple iPhone 7 Plus, Huawei P20 Pro, Bioheat transfer equation, Mobile phone, Specific absorption rate.

The identical twins (Monozygotic) are siblings created from the division of one fertilized egg (zygote), so they will be identical in their genetic characteristics and therefore in their phenotypic traits to a very large extent. Among these traits is the voice or the voiceprint of these twins. This research aims to suggest a method to determine the extent of the similarity and the difference between the voiceprints between the brothers of the identical twins and thus, it is possible to distinguish between their voices. This study relied on using a number of audio clips collected from 35 identical twins. The proposed method is based on the use of the spectrogram that represents the voiceprint of the twins. The spectrogram is a two-dimensional function that can be used in the Neutrosophic Transformation to convert the voiceprints to the Neutrosophic domain represented by three membership functions (True, False, and Indeterminate). The results showed that the average extent of the similarity ratio between twins’ voices (True membership) is 67.6%, the difference ratio (False membership) is 32.3%, and the indeterminacy membership function ratio is 18.2%.