Mobile telephone radio wave effects

Like all other radio communication applications, mobile telephony uses radio waves to carry the information, like voice, text and images, through the air. Radio waves are a kind of electromagnetic fields (EMF) that are also called radio frequency fields or radio frequency energy. Electromagnetic fields are present in our every day life, both naturally and from man-made sources. Radio waves travel with the speed of light. They consist of an electric and a magnetic component, which vary periodically in time. The number of oscillations per second is called the frequency. The intensity of the radio waves is normally expressed as power density, and sometimes also as electric and magnetic field strength. The radio wave intensity is dependent on the distance to the transmitter, for example a mobile phone or a base station antenna, and to the output power of the transmitter. The lower the power and the longer the distance, then the lower the intensity will be.

Different types of electromagnetic fields have different frequencies. Visible light, for instance, has higher frequencies than radio waves, but lower than ultraviolet light. Electromagnetic waves with frequencies higher than ultraviolet light are called ionizing radiation, which has sufficient energy to break molecular bonds and thereby the potential to cause damage to biological tissue. X-rays and gamma rays are examples of ionizing radiation. Radio waves belong to the lower frequency part of the electromagnetic spectrum, which is called non-ionizing radiation. Here the electromagnetic energy is too low to break molecular bonds.

When a person is exposed to the radio waves from mobile phones or base stations, most of the energy will be reflected by the body or travel around it (called diffraction). Some of the energy will however be absorbed in the tissues at the surface of the body. Inside the body certain molecules, like water, will start to move or rotate due to the presence of the electromagnetic fields. By “friction” the energy is converted into heat. If the radio wave intensity is very high, the heating may be significant and potentially detrimental. The power used by mobile phones is very low and the tissue heating due to radio wave absorption is too small to be noticeable. The specific absorption rate, SAR, is used to specify the amount of radio frequency energy absorbed in the body. SAR is expressed in the unit watts per kilogram (W/kg).

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Radio, a potential medium for education

While admiring the growth of radio production and broadcast technology, Madhu Ranjan feels that it still continues to be an under-utilized technology in education. According to her, radio has enormous potential to improve distance education systems especially when integrated with other technologies such as television, mobile telephones, and the Internet.

Soon after its invention in the late 1890s, radio, due to its information and

entertainment value, vast reach, and immediacy, became the most popular means of mass communication around the world.

With the arrival of television, the birth of satellite broadcasting technology, and later the Internet, radio’s listener base began to erode and its importance diminished.  In the 1970s, however, radio (FM band) once again gained popularity, especially among young listeners.

Today, improved broadcasting quality, more innovative and entertaining content, and new technological developments in fields such as digital and satellite radio have made radio a resurgent medium, extremely popular in the fields of advertising and entertainment. Affordability, portability, and access indoors and outdoors give radio a clear edge over other media. Additionally, radio is increasingly becoming a more dynamic medium, as it is integrated into other new technologies such as television, mobile telephones, and the Internet.

This has opened up new opportunities for a variety of forms of delivery and access. For example, portable, low-cost FM transmitting stations have been developed and digital radio systems that transmit via satellite are being set up in many parts of the world. Internet streaming audio software technology now allows a global audience to listen to news from a distant country. In addition, the development of wind-up and solar radios utilizing inexpensive power sources allows radio to can cut across geographic, economic, and cultural boundaries.

However, radio still continues to be an under-utilized technology in education. This is somewhat surprising because, for a learner, radio is a simple, user friendly, accessible, and a well-established medium. From an educational provider’s point of view it is easy and inexpensive to set up, produce, and broadcast programs. Most nations currently have the engineering skills and broadcasting talent to apply this technology to education.

Today, many schools, colleges, universities, and other organizations use distance education systems. While developing a distance education system, factors such as cost effectiveness, efficiency, and the availability of appropriate communication technologies, as well as access and equity issues, particularly those related to gender, language, social status, and religion, are the most important considerations.

Other factors to consider relate to how distance learners can best use their higher order thinking skills and how they can cope with the limitations of time, age, gender, and language. Radio is able to address these issues while reaching a diverse group of learners and can be valuable in many different distance learning environments including schools, colleges and universities, businesses, and public sector organizations.

For distance education providers, radio is a cheaper alternative to other communication technology mediums. Producing interactive radio programs in distance education requires only low-priced equipment compared with other cutting-edge technologies. Educational institutions do not need to spend much money for establishing interactive radio studios in their organizations.

Learners are equally fortunate, because they do not have to buy or rent the costly and complex equipment required by TV and the Internet. There are no boundaries to broadcasting educational programs with interactive radio throughout the world and as long as learners have access to a very low-cost radio, they can listen to programs wherever they are; riding in their cars, traveling by bus or train, or working at home.

Moreover, interactive distance educational programs can be recorded for learners via inexpensive equipment, such as cassettes, CDs, or MP3 players. Educational radio helps provide equal access to knowledge for everyone by breaking digital walls around the world.

Interactive radio programs allow people with disabilities (with the exception of the hearing-impaired) to hear the voices of instructors, classmates, and experts, enhancing their ability to learn. While listening to interactive radio programs, learners have more time to construct knowledge.

Community radio is also an immensely powerful technology for the delivery of information with enormous global potential.  It is particularly powerful in providing access to information for marginalized populations, including women, minorities, and the poor, who often do not have access to more cutting edge technology. Radio can expand opportunities for the intended beneficiaries of development to participate in the in the development agenda, which can appropriately and adequately respond to their needs and aspirations.

Currently, the benefits of radio as a learning medium are overlooked. Conventional wisdom assumes that high-cost communication media ensure better interactive distance learning. Radio, however, when incorporated with interactive learning approaches, has enormous potential to improve distance education systems. In a very imaginatively designed program – funded by USAID and implemented by EDC – that makes the process of teaching-learning interesting and meaningful, radio lessons that introduce substantial interaction among students and teachers are improving classroom interaction in close to 300,000 government schools reaching over 25 million primary school students across several states in India.

Many interventions around the world are using radio innovatively; successfully enhancing the quality of teaching learning in traditional classroom settings, imparting health messages to communities; and providing useful information on agriculture to farmers.  Although it is not currently being exploited to its full potential, radio is a medium with tremendous potential, particularly for educational purposes. Get payday advance service for easy payment

Satellite radio for education

EDUSAT, according to the Indian Space Research Organization (ISRO), is the first exclusive satellite for serving the educational sector. It supports radio broadcasting, along with audio-video on C-band and Ku-band, and is built around the concept of digital interactive classrooms and a multimedia system.

The satellite has multiple regional beams covering different parts of India, which theoretically enables programmes to be broadcast in relevant local languages – India has 18 official languages and over 1500 dialects. “India will require 10,000 new schools each year and meeting the teaching needs on such a scale [by conventional methods] will be impossible,” Madhavan Nair, chairman of ISRO told New Scientist at the launch of the satellite.

EDUSAT can provide connectivity to schools, colleges and higher levels of education and also support non-formal education including developmental communication. The nation-wide beams are being harnessed by agencies like IGNOU, NCERT and the All India Council for Technical Education (AICTE), to reach hundreds of Receive Only Terminals (ROTs) and Satellite Interactive Terminals (SITs) located in schools and colleges, many in remote areas.

Content generation is the responsibility of user agencies, but it is a matter of concern that, over a year after the satellite was launched, much of its capacity is lying idle.

Satellite access for radio broadcasting is also available on other platforms like WorldSpace, which offers a ‘development channel’ to agencies like Equal Access for networking community FM channels (as in Nepal), or for directly broadcasting development and educational programmes for community listening on WorldSpace receivers.

The promise of radio
U.K. Open University’s notable success with educational radio has demonstrated how invaluable radio can be for weak students, who benefit from the medium as a supplementary learning tool. But the use of radio for distance education in India, as mentioned earlier, has had mixed results. AIR’s educational broadcasts are

All the same, it has been amply proved that radio – rightly used – can improve educational quality and relevance, lower educational costs and improve access to education, particularly for disadvantaged groups. It is most effective when supported by trained facilitators, group learning, group discussion, feedback and the use of multimedia approaches.

There is no single ideal format for educational radio. Innovative programming like those developed by Sesame Workshop in Africa, for instance, offer some very effective approaches to non-formal education over radio. Recently, AIR agreed to a proposal from Sesame Workshop India to provide airtime on national and regional radio channels for locally produced versions of the universally popular ‘Sesame Street’. The programmes would be aimed at pre-schoolers, and would also provide under-served children with access to educational media, especially in rural areas.

India spends just 3.4% of its GNP on education. Over 35% of the population is illiterate, and the drop out rate in schools is staggeringly high, with 40% of all school-going children dropping out during the primary stage itself. The percentage of dropouts goes up to 67% by Class X. The Supreme Court of India (in 1993) has declared education of children up to 14 years to be a fundamental right, but school attendance is related to the perceived importance of education by parents, and also to socio-economic factors.

Despite rapid developments in communication technologies in the last few decades, radio broadcasting remains the cheapest mode of mass communication in India, catering equally to the needs of the rich and the poor, rural and the urban masses and reaching the remotest parts of the country. In a country where the literacy rate is 65%, and fewer than 50% of homes are electrified, the humble transistor radio plays a vital role in the country’s socio-economic and cultural development.

Rural and deprived communities, with low literacy rates and little access to formal education, stand to benefit the most from distance learning through community radio. If and when such communities are permitted to set up their own low power radio stations – and 4000 such community radio stations are possible in India, according to government estimates – then we could witness a revolution in education far beyond anything dreamt of by the purveyors of digital technology in a digitally divided country.

Using radio for education and community development is part of the 75-year-old Reithian ambition for radio broadcasting. Children and youth can be easily and cheaply trained, and the goals of universal primary and secondary education for all can be reached more easily with broadcast support. Among the poor and marginalized people of the country, radio could even create a new class of people – educated but illiterate.

Campus radio stations

In December 2002, the Ministry of Information and Broadcasting released its ‘Community Radio Guidelines’. Though nominally ‘community’ radio, the policy restricts the radio licenses under this scheme to ‘well-established educational institutions’. The licensing process proved so cumbersome that India’s first campus-based community radio station was launched only by 2004 (Anna University’s 90.4 Anna FM).

Against optimistic projections of 1000 campus stations coming up in a year, only 75 odd educational institutions have applied for a campus radio licenses so far, and of these, 15 stations have become operational.

Most of the campus licenses have gone to universities, engineering colleges and mass communications institutions, along with a Despite rapid developments in communication technologies in the last few decades, radio broadcasting remains the cheapest mode of mass communication in India that can benefit rural and deprived communities with low literacy rate and little excess to education sprinkling of well-heeled schools. Transmitting over a range of 5-10 kilometres, their FM radio stations are expected to serve the community beyond the campus walls, and to produce programmes ‘on issues relating to education, health, environment, agriculture, rural and community development’, according to the government’s Community Radio Guidelines (www.mib.nic.in).

Needless to say, the campus stations that try to live up to this confused mandate – and many of them do – sound very much like the public service broadcaster on which they seem to be closely modelled. You don’t need checks to maintain campus radio stations because of students support.