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Radiation Pattern from the cell tower Antenna has been drawn for basic understanding of a radiation pattern. Page1:This diagram was mainly used to describe why on a certain building the radiation levels vary from one apartment(say 7th floor) to the apartment above or below (6th and 8th floor) in a building at Khar (West), Mumbai.The radiation pattern of a cell tower antenna is defined by its lobes. Radiation will be highest from the primary lobes in the horizontal direction. There is also radiation from secondary lobes.As seen in the figure, the readings that will be taken in between the lobes will be much lesser. As seen the figure, the radiation will also be high vertically downward from the secondary lobes. This is what most mobile operaters hide or are not aware of in India. Page 2:Distance is another critical factor. The power density varies by (1/R2), where is R is the distance. People living within 50-300meter radiaus are in the high radiation zone. This data has been taken from a another country outside India. In the US for example, residential areas generally have amplifiers of 1-2 W. However in India, in many places even 100 to 200W of amplifiers are used and their are clusters of antennas from multiple operators on the roof top of several residential and office premises.Page 3:Simulated radiation pattern of a cell tower antenna from Prof. Girish kumar, IIT Bombay. Page 4:USHA KIRAN BUILDING - several cancer casesThrough the help of the above typical radiation pattern, let’s analyze the news reported in Mid-day, Mumbai dated Jan. 3, 2010, which stated - “Mumbai's swanky Usha Kiran building says the four cancer cases there could be linked to mobile towers installed on the facing Vijay Apartments”. The picture taken from the Usha Kiran building of the several antennas installed on the seventh floor of Vijay Apartments is shown in Fig. pn Page 4. People living in the 6th, 7th and 8th floor in the opposite building will get maximum radiation as they are in the main beam direction. People living on the other floors will receive lesser radiation as beam maxima is reduced considerably as can be observed from vertical radiation pattern. In the horizontal direction again, people living in the front side of the antenna will receive much higher radiation compared to people living in the back side of antenna. http://www.mid-day.com/news/2010/jan/030110-mobile-tower-cancer-cases-carmichael-road-posh-areas.htmRecently (as on Jan 2011) two more cancer cases have been reported on the 5th and on the 10th floor.
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Radiation Pattern of a Cell Tower Antenna
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Primary Lobe
Secondary Lobes
5/12/2011 1Neha Kumar
Radiation Pattern of a Cell Tower Antenna
People living within 50 to 300 meter radius are in the
high radiation zone (dark blue) and are more prone to
ill-effects of electromagnetic radiation.
Propagation of "main beam“ from antenna mounted on a tower or roof top
Reference - Mobile Telecommunications and health research programme (MTHR)
Report 2007 – Pg 50 - http://www.mthr.org.uk/documents/MTHR_report_2007.pdf
5/12/2011 2Neha Kumar
Radiation Pattern of Antenna
5/12/2011 3Neha Kumar
Usha Kiran Building, Mumbai – several cancer
Six cancer cases in consecutive floors (5th,6th, 7th,8th and 10th)
directly facing and at similar height as the mobile phone towers of
four telecom companies placed on the roof of opposite building.
Usha Kiran Building
5/12/2011 4Neha Kumar
