تقييم مستويات الاشعاع الكهرومغناطيسي في المناطق الخارجية الصادرة عن أنظمة الارسال اللاسلكية في شمال الضفة الغربية – فلسطين

Exposure to electromagnetic fields is a major public concern due to the possible hazardous effects on health caused by exposure to these radiations. The aims of this study were to measure radiofrequency radiation levels from different wireless systems and to compare the results with the recommended limits by the World Health Organization (WHO) which should be less that 450 μw/cm2. The study was a cross-sectional study that was conducted in different cities and villages from the northern governorates in the West Bank; Jenin, Tulkarm, Nablus, Qalqilya, Tubas and Sal fit. To measure the radiation levels ranging from 80 MHz to 2 GHz, a Portable Field Strength Meter with the suitable set of antennas was used. This frequency range covers the radiations from different sources as mobile phone base stations, local radio and television stations, mobile phones, Wireless Local Area Network, Bluetooth, wireless computer periphery and even microwave ovens. Points close to mobile phone base stations and local radio and television stations in addition to randomly selected points were included. The scanning process for each point was done twice and the higher reading was included in the analysis. The results were compared to the recommended limits of radiations by WHO. Also, a questionnaire was distributed to evaluate people knowledge and perception regarding radiations. A total of 2000 readings were obtained with a mean ± SD = 0.25 ± 0.214 μw/cm2. The highest reading was 1.91 μw/cm2. All the readings were below the limits of radiations recommended by the WHO. Most of the readings in the tested area 1184 (59.2%) were between 0.1 -0.45 μw/cm2 which are 1000-4500 time less than the maximum allowed level (450 μw/cm2), 527 (26.35%) readings were \u3c0.1 μw/cm2, 271 (13.55%) reading were between 0.45-1 μw/cm2 and the rest 17 (0.85%) were \u3e1 μw/cm2 which were still 236-450 times less than the allowed WHO level. Regarding the questionnaire part, most of the participants use mobile phones frequently, they think radiations are dangerous and can cause cancer, they prefer not to have mobile base stations close to their living places. In this study, a scanning for all electromagnetic radiation sources caused by different sources of wireless communication systems showed theoretically no dangerous radiation levels and all the recorded levels were much lower than the recommended levels by the WHO. Most people feel afraid from radiations and think they are dangerous

Transmitter precoding and code-sharing techniques using block transmission system [TK1-9971].

Dewasa ini, perkhidmatan komunikasi bergerak telah meledak dengan begitu pantas sekali dalam masyarakat kita. Kesemua sistem komunikasi selular yang ada kini menggunakan teknologi digital. Recently, mobile communications services are penetrating into our society at an explosive growth rate. All of the current cellular communication systems have adopted digital technology

Mobile Computing - Technology and Applications

Nowadays, mobile communication services are penetrating into our society at an explosive growth rate. Applications in mobile devices offer limitations, restriction, and guidelines on how mobile software can be used in order to simplify the mobile usage. As smart phones and tablets are becoming the daily computing device of choice for young ages, it is expected that mobile applications and services should be as flexible, high quality, and secure as the desktop systems. In this book, latest trends in mobile computing will be discussed. In the first section, cloud computing topics will be discussed widely into four chapters to give information to the reader about topics such as challenges, services, edge computing, and distributed clouds needed to integrate this promising issue into the next generation