GPRS

General Packet Radio Service or GPRS is a GSM based packet switched technology. It enables connections based on Internet Protocols which support wide range of enterprise and commercial applications. The radio and network resources accessed on-demand basis, when data actually needs to be transmitted between the mobile user and the network. The data is divided into packets and is then transferred via the radio and core network.

GPRS facilitates instant connections whereby information can be sent or received immediately as the need arises, subject to radio coverage, in the way that the GPRS users are always connected (always on). GPRS enables several new applications. GPRS will enable Internet applications, from web browsing to chat, location based applications, e-commerce etc over the mobile network. Other new applications for GPRS, include file transfer and the ability to remotely access and control/monitor house appliances and machines.

The increased functionality of GPRS will decrease the incremental cost to provide data services, an occurrence that will, in turn, increase the penetration of data services among consumer and business users. In addition, GPRS will allow improved quality of data services as measured in terms of reliability, response time, and features supported.

GPRS offers up to ~171.2 Kbps, depending on the network availability, channel coding scheme and terminal capability. This increase in speed with respect to GSM is achieved by using more than one timeslot of the TDMA frame. Due to the packet switched characteristics the allocation of the available timeslots may vary from one instant to the next (e.g. it may have 8 timeslots at one time and 4 later on).

To use GPRS, users specifically need a mobile phone or terminal that supports GPRS, a subscription to a mobile telephone network that supports GPRS and the use of GPRS must be enabled for that user. GPRS is important as a migration step toward third-generation (3G) networks. GPRS will allow network operators to implement an IP-based core architecture for data applications, which will continue to be used and expanded upon for 3G services for integrated voice and data applications. In addition, GPRS will prove a testing and development area for new services and applications, which will also be used in the development of 3G services. It is possible that some mobile Network operators provide Automatic access to the GPRS, others will require a specific knowledge of how to use their specific model of mobile phone to send or receive information through GPRS.

Should I Worry About Mobile Phones?

Should I Worry About Mobile Phones?

We have all seen the headline about mobile phones. If you believed what you read, you’d throw your mobile away for fear of everything from cancer to infertility.

And that's before we even start to think about mobile phone base stations. Forty percent of people surveyed believed that masts can cause health problems.

So what's the truth? Should we worry about our mobile phones?

Can mobile phones cause cancer?

Some past studies had suggested an increased risk of acoustic neuroma - a tumour of the nerve connecting the ear and the brain - but others did not.

A vast amount of research has been done into mobile phone handsets. A few studies have claimed that some phones can cause higher rates of brain tumours. But don't throw your phone in the bin just yet.

Results which suggest that mobiles might damage health are actually rare. Those that do tend to have been done with old style analogue phones, which use a much stronger signal than modern phones. The general scientific opinion at the moment is that the benefits of mobile phones seem to outweigh any known dangers.

What about base stations?

So, the jury is still out on mobile phone handsets. But what about mobile phone base stations? Is there any clearer evidence that they cause health problems?

Again there is conflicting information. According to the Stewart report, there is no evidence that there are any adverse health effects. However, many people up and down the country disagree.

Richard visited a 'sick-mast village', which has one of the highest concentration of masts in the country. The residents - with tin-foil sheilding in their houses - are living in fear. They are convinced that the masts are causing a host of symptoms. Are their problems caused by the masts, or could they be caused by worry?

The Should I Worry About team decided to carry out a test. We put ten students in a house for ten days and erected a mobile mast in the garden. We weren't entirely honest with them though; we told the students the mast was on at the start of the experiment and off at the end. In fact it was off at the start and on at the end. What's interesting is that the only time any of the students felt ill was when the mast was OFF but they thought it was ON.

Our small experiment suggests that people's fear of phone masts can be a factor in making them feel unwell. There are some people though who might be affected by phone masts and a large study is just beginning at Essex University to try to spot these hypersensitive people.

One thing we do know is that it helps if operators involve the public when erecting masts. In practice this doesn't always happen. However, operators have a duty to keep local communities informed, so if you see a mast appear suddenly in your area - make a fuss.

Should we all chuck our phones in the bin?

Senior investigator Professor Anthony Swedlow said: "Whether there are longer-term risks remains unknown, reflecting the fact that this is a relatively recent technology."

Dr Michael Clark from the Health Protection Agency said: "This is good news but we still need to be a bit cautious."

Dr Julie Sharp, senior science information officer at Cancer Research UK, said: "This study provides further evidence that using mobile phones does not increase the risk of brain tumours.

"However, it is important that researchers continue to monitor phone users over the coming years as mobiles are still a relatively new invention."

The research is part of a bigger study that will be published next year.

A Swedish study identified an increased risk of acoustic neuromas among people who had used mobile phones for 10 years or more.

People have been concerned that the radiofrequency from phones might cause cancers, despite the absence of a known biological mechanism for this.

Probably not. The benefits do seem to outweigh any possible dangers, and there are things you can do to protect yourself from any possible health effects. So if you are worried, use a hands- free kit. When your signal is very low, switch your phone off because it's working extra hard at those times. And if you're under 16, stick to texting whenever you can

Mobile Impacts

Human health impacts

Since the introduction of mobile phones, concerns have been raised about the potential health impacts from regular use. As mobile phone penetrations grew past fixed landline penetration levels in 1998 in Finland and from 1999 in Sweden, Denmark and Norway, the Scandinavian health authorities have run continuous long term studies of effects of mobile phone radiation effects to humans, and in particular children. Numerous studies have reported and most studies consistently report no significant relationship between mobile phone use and health. Studies from the Institute of Cancer Research, National Cancer Institute and researchers at the Danish Institute of Cancer Epidemiology in Copenhagen for example showed no link between mobile phone use and cancer.The Danish study only covered analog mobile phone usage up through 1995, and subjects who started mobile phone usage after 1995 were counted as non-users in the study.The health concerns have grown as mobile phone penetration rates throughout Europe reached 80%–90% levels earlier in this decade and prolonged exposure studies have been carried out in almost all European countries again most reporting no effect, and the most alarming studies only reporting a possible effect. However, a study by the International Agency for Research on Cancer of 4,500 users found a statistically significant link between tumor frequency and mobile phone use.

The link between cellphones and low sperm quality suggests that the radiation emitting from mobile phones may be potentially dangerous and should be considered as such.

There has been one reported death from a mobile phone malfunction. In 2007, it was reported that a mobile phone battery exploded killing a man in Korea.It was later discovered to be a lie.

Environmental impacts

Like all high structures, cellular antenna masts pose a hazard to low flying aircraft. Towers over a certain height or towers that are close to airports or heliports are normally required to have warning lights. There have been reports that warning lights on cellular masts, TV-towers and other high structures can attract and confuse birds. US authorities estimate that millions of birds are killed near communication towers in the country each year.

An example of the way mobile phones and mobile networks have sometimes been perceived as a threat is the widely reported and later discredited claim that mobile phone masts are associated with the Colony Collapse Disorder (CCD) which has reduced bee hive numbers by up to 75% in many areas, especially near cities in the US. The Independent newspaper cited a scientific study claiming it provided evidence for the theory that mobile phone masts are a major cause in the collapse of bee populations, with controlled experiments demonstrating a rapid and catastrophic effect on individual hives near masts.Mobile phones were in fact not covered in the study, and the original researchers have since emphatically disavowed any connection between their research, mobile phones, and CCD, specifically indicating that the Independent article had misinterpreted their results and created "a horror story".While the initial claim of damage to bees was widely reported, the corrections to the story were almost non-existent in the media.

Mobile phones and driving safety

Prevalence

The U.S. National Highway Traffic Safety Administration (NHTSA) reported that in 2005 about 10% of all vehicles on the road at any given daylight hour were using a mobile phone, up from about 8% the previous year.

Handsets

Research indicates that using a mobile phone while driving is as dangerous as driving while intoxicated and mobile phone use while driving is far more prevalent than drunk-driving. Talking and driving at the same time lowers the driver's reflexes, rendering them slower to react to and avoid other drivers.

One study of almost seven hundred Canadian drivers showed a rate of collision four times higher when using a mobile phone than when a mobile phone was not being used. A study in The New England Journal of Medicine reports that drivers who used mobile phones while driving were four times more likely to crash than those who don't, a rate equal to that for drunken driving at the 0.08 g/dL blood alcohol concentration (BAC) level.[citation needed]

An experiment conducted by the American television show Mythbusters concluded that use of mobile phones while driving poses a similar risk as someone operating a vehicle while under the influence of alcohol.

Hands-Free

Several studies argue that the increased "cognitive workload" involved in holding a conversation is the real danger, not the use of hands. Several studies carried out at the Accident Research Unit at the University of Nottingham have warned of the dangers posed by driving while talking on a mobile phone.As these studies deal with the effect of increased attentional load on driving performance, they also apply to hands-free phones, which are considered by some countries to be safe. The major problem is that the person with whom the driver is conversing cannot see the traffic situation and therefore does not regulate their level of conversation to allow the driver to concentrate when, say, approaching a junction. This problem does not apply to conversations with a passenger, as passengers can regulate the flow of conversation according to the perceived level of danger, and also provides a second pair of eyes to spot hazards.

A study carried out by the University of Utah found that driving while using a mobile phone is "at least as dangerous as driving while over the legal alcohol limit". They also found that hands-free devices do not reduce the distraction caused by talking on a mobile phone. According to a study published in the British Medical Journal and funded by the Insurance Institute for Highway Safety, there was only a slight safety benefit from using a hands-free phone. The study showed that drivers who use cell phones, even hands-free models, are four times as likely to be involved in wrecks involving a serious injury than are drivers who do not use cell phones.

from: wikipedia

Wireless electronic devices and health

From Wikipedia, the free encyclopedia

With the focus on health concerns of mobile phones, people are questioning the health risks of other wireless devices now being increasingly used at work and in the home, such as wireless local area networks, DECT and other cordless phones, Bluetooth devices, and other wireless technology. There is currently no scientific literature on the effects of wLAN and Bluetooth technologies, and the literature on mobile and cordless phones is mixed - see Mobile phone radiation and health.

The World Health Organization have acknowledged that electromagnetic fields are influencing the environment (but not people), and that some people are worried about possible effects.[1] In response to public concern, the World Health Organization established the International EMF Project in 1996 to assess the scientific evidence of possible health effects of EMF in the frequency range from 0 to 300 GHz. They have stated that although extensive research has been conducted into possible health effects of exposure to many parts of the frequency spectrum, all reviews conducted so far have indicated that exposures are below the limits recommended in the ICNIRP (1998) EMF guidelines, covering the full frequency range from 0-300 GHz, and do not produce any known adverse health effect.

International guidelines on exposure levels to microwave frequency EMFs such as ICNIRP limit the power levels of wireless devices and it is uncommon for wireless devices to exceed the guidelines. However, these guidelines only take into account any thermal effects, as no other effects have been discovered. The chairman of the Health Protection Agency, Sir William Stewart, has said that "evidence of potentially harmful effects of microwave radiation had become more persuasive over the past five years. His report said that while there was a lack of hard information of damage to health, the approach should be precautionary."[1] The HPA, however, disagrees with his assessment, and claims that there is no risk and no need for precaution. Sir William has resisted any calls to further explain his comments.

Mobile phones and cancer

Mobile phones and cancer

In 2006 a large Danish study about the connection between mobile phone use and cancer incidence was published. It followed over 420,000 Danish citizens over 20 years and showed no increased risk of cancer. The German Federal Office for Radiation Protection (BfS) consider this report as inconclusive.

In order to investigate the risk of cancer for the Mobile Phone user, a cooperative project between 13 countries has been launched called INTERPHONE. The idea is that cancers need time to develop so only studies over 10 years are of interest.

The following studies of long time exposure have been published:

* A Danish study (2004) that took place over 10 years and found no evidence to support a link.

* A Swedish study (2005) that draws the conclusion that "the data do not support the hypothesis that mobile phone use is related to an increased risk of glioma or meningioma."

* A British study (2005) that draws the conclusion that "The study suggests that there is no substantial risk of acoustic neuroma in the first decade after starting mobile phone use. However, an increase in risk after longer term use or after a longer lag period could not be ruled out."

* A German study (2006) that states "In conclusion, no overall increased risk of glioma or meningioma was observed among these cellular phone users; however, for long-term cellular phone users, results need to be confirmed before firm conclusions can be drawn."

* A joint study that draws the conclusion that "Although our results overall do not indicate an increased risk of glioma in relation to mobile phone use, the possible risk in the most heavily exposed part of the brain with long-term use needs to be explored further before firm conclusions can be drawn."
Other studies on cancer and mobile phones are:

* Tumour risk associated with use of cellular telephones or cordless desktop telephones, that states: "We found for all studied phone types an increased risk for brain tumours, mainly acoustic neuroma and malignant brain tumours".

* A Swedish study (2004) concludes: "Our findings do not indicate an increased risk of acoustic neuroma related to short-term mobile phone use after a short latency period. However, our data suggest an increased risk of acoustic neuroma associated with mobile phone use of at least 10 years' duration.".

Electromagnetic hypersensitivity syndrome

Some users of mobile handsets have reported feeling several unspecific symptoms during and after its use, such as burning and tingling sensations in the skin of the head and extremities, fatigue, sleep disturbances, dizziness, loss of mental attention, reaction times and memory retentiveness, headaches, malaise, tachycardia (heart palpitations) and disturbances of the digestive system. Some people, implying a causal relationship, have named this syndrome as a new diagnostic entity, EHS or ES (electrosensitivity). The World Health Organization prefers to name it "idiopathic environmental intolerance", in order to avoid the implication of causation.

source: wikipidia

Mobile phone radiation and health

Mobile phone radiation and health concerns have been raised, especially following the enormous increase in the use of wireless mobile telephony throughout the world (as of August 2005, there were more than 2 billion users worldwide). This is because mobile phones use electromagnetic waves in the microwave range. These concerns have induced a large body of research (both epidemiological and experimental, in non-human animals as well as in humans). Concerns about effects on health have also been raised regarding other digital wireless systems, such as data communication networks.

The World Health Organization has concluded that serious health effects (e.g. cancer) are very unlikely to be caused by cellular phones or their base stations, and expects to make recommendations about mobile phones in 2007–08.

However, some nation's radiation advisory authorities, including those of Austria, Germany, and Sweden, recommend their citizens to minimize radiation. Examples of recommendations are:

* Use hands-free to decrease the radiation to the head.
* Keep the mobile phone away from the body.
* Do not telephone in a car without an external antenna.

Still, the use of "hands-free" is not recommended by the British Consumers' Association

Health hazards of handsets

Part of the radio waves emitted by a mobile telephone handset are absorbed by the human head. The radio waves emitted by a GSM handset, can have a peak power of 2 watts, and a US analog phone had a maximum transmit power of 3.6 watts. Other digital mobile technologies, such as CDMA and TDMA, use lower output power, typically below 1 watt. The maximum power output from a mobile phone is regulated by the mobile phone standard it is following and by the regulatory agencies in each country. In most systems the cellphone and the base station check reception quality and signal strength and the power level is increased or decreased automatically, within a certain span, to accommodate for different situations such as inside or outside of buildings and vehicles.

The rate at which radiation is absorbed by the human body is measured by the Specific Absorption Rate (SAR), and its maximum levels for modern handsets have been set by governmental regulating agencies in many countries. In the USA, the FCC has set a SAR limit of 1.6 W/kg, averaged over a volume of 1 gram of tissue, for the head. In Europe, the limit is 2 W/kg, averaged over a volume of 10 grams of tissue. SAR values are heavily dependent on the size of the averaging volume. Without information about the averaging volume used comparisons between different measurements can not be made. Thus, the European 10-gram ratings should be compared among themselves, and the American 1-gram ratings should only be compared among themselves.

Thermal effects

One well-understood effect of microwave radiation is dielectric heating, in which any dielectric material (such as living tissue) is heated by rotations of polar molecules induced by the electromagnetic field. In the case of a person using a cell phone, most of the heating effect will occur at the surface of the head, causing its temperature to increase by a fraction of a degree. In this case, the level of temperature increase is an order of magnitude less than that obtained during the exposure of the head to direct sunlight. The brain's blood circulation is capable of disposing of excess heat by increasing local blood flow. However, the cornea of the eye does not have this temperature regulation mechanism. Premature cataracts are known as an occupational disease of engineers who work on high power radio transmitters at similar frequencies.[citation needed] Premature cataracts however, have not been linked with cell phone use, possibly because of the lower power output of mobile phones.

It has been claimed that some parts of the human head are more sensitive to damage from increases in temperature, particularly in anatomical structures with poor vasculature, such as nerve fibers. More recent results from a Swedish scientific team at the Karolinska Institute (Lonn, Ahlbom, Hall and Feychting) have suggested that continuous use of a mobile phone for a decade or longer can lead to a small increase in the probability of getting acoustic neuroma, a type of brain tumor. The increase was not noted in those who used phones for less than 10 years.

Non-thermal effects

The communications protocols used by mobile phones often result in low-frequency pulsing of the carrier signal.

Some researchers have argued that so-called "non-thermal effects" could be reinterpreted as a normal cellular response to an increase in temperature. The noted German biophysicist Roland Glaser, for example[6], has argued that there are several thermoreceptor molecules in cells, and that they activate a cascade of second and third messenger systems, gene expression mechanisms and production of heat shock proteins in order to defend the cell against metabolic cell stress caused by heat. The increases in temperature that cause these changes are too small to be detected by studies such as REFLEX, which base their whole argument on the apparent stability of thermal equilibrium in their cell cultures.

Swedish researchers from the University Lund, Salford, Brun, Perrson, Eberhardt and Malmgren, have studied the effects of microwave radiation on the rat brain. They found a leakage of albumin into brain via a permeated blood-brain barrier.

Genotoxical effects

Research from Greece towards the end of 2006 found a direct causal relationship between mobile phone radiation and DNA damage.In December 2004 a pan-European study named REFLEX (Risk Evaluation of Potential Environmental Hazards from Low Energy Electromagnetic Field (EMF) Exposure Using Sensitive in vitro Methods), involving 12 collaborating laboratories in several countries showed some compelling evidence of DNA damage of cells in in-vitro cultures, when exposed between 0.3 to 2 watts/kg, whole-sample average. There were indications, but not rigorous evidence of other cell changes, including damage to chromosomes, alterations in the activity of certain genes and a boosted rate of cell division.

source:wikipidia