Tuesday, February 16, 2010
Base Station Antennas to the Rescue!
If you have wondered what good will the subject 'Antenna and Microwave Engineering' do, this article is a must-read for you.
The amount of research that is underway on this very antenna is phenomenal. One such research is mentioned below. This makes one realise that the beauty (and complexity) of research lies in the simplest of concepts.
We all know that rain attenuation is one major interferance factor in mobile phone signal transmission. It is a terrible nuisance, for which methods are taken to account for the resulting signal attenuation that occurs. Rieckermann and his research team at Eawag’s Urban Water Management department at the Swiss Federal Institute of Aquatic Science and Technology devised a technique by which rainfall could be measured with greater precision and accuracy using this very concept of 'rain attenuation.'
The idea is very simple. They asked the mobile operator Orange, to provide them with the exact signal attenuation data which enabled them to calculate the intensity of rainfall between two base station antennae. This calculation was repeated for all the antennae (and hence, pretty easily, covered the entire area/region effectively). Now they had the rainfall intensity in a particular region, and this proved to be superior to the readings made by weather radars or rain gauges. Radar signals can be severely affected by heavy rainfall, but mobile signals are dependent on a network of overlapping microwave radio links and these can be easily analysed to calculate the amount of rainfall that has occured, and whether a rain-storm has started or not.
What exactly will this research produce? The concept behind this is that rainfall intensity measured in a more accurate manner will give analysts a clear idea of how much more rain to expect. This data will be used to prevent the frequent water pollution - something that Pakistan is very very familiar with. The rainwater mixes with sewage in pipes, which leads to sewer systems overloading and this dirty water pours into the streets and dirties everything around it. This contaminated water is discharged into the streams, rivers and canals that lead to further water contamination and harming sea life. So if weather analysts and environment engineers have a better way to predict rainfall intensity, steps can be taken to prevent the sewers from overflowing, and thus a huge step can be taken towards combatting marine pollution.
Zurich-based researchers gathered data from 23 microwave radio links, compared these signals with data measured from 13 rain gauges, 2 disdrometers (A disdrometer is an instrument that measures the drop size distribution and velocity of falling hydrometeors) and Albis weather radar station controlled by the MeteoSwiss. This analysis went on for two months and thus became the basis of the researchers' findings. They are hopeful of including drop size distribution in their carefully calibrated model so as to account for the fact that huge raindrops increase the attenuation factor, but do not mean that rain intensity is high. These calculations and modeling aspires to achieve early warning before heavy rainfalls, to preserve a pollution-free atmosphere, especially the water. One can't help wishing this kind of practically applicable research takes place in Pakistan as well, for, after all, we are a country whose teledensity hit the 59.60 mark as the year 2009 ended. The rise in telecommunications awareness and progress in the country warrants some research work to be done in this area, especially if it is related to a very noble cause -- prevention of overflowing sewage systems.