If you need to measure rainfall rate, you need a rain gauge. For propagation work you need 1-minute integration time - so a garden rain-gauge will not do. It will have to be a tipping-bucket or siphon rain gauge. For high dynamic range (rain-fall rates exceeding 100 mm/h) an optical rain gauge is recommended. For propagation studies over long paths over hilly terrain one rain gauge might not be sufficient, moreover, to achieve a good results you should obtain long-term (= multi-year) statistics. Anything less than a full year is not representative.

Now, a cheaper solution is to ask the local meteorological service for rain statistics - here the problem could be that they did not record with 1 minute integration time.

Finally, you can get the rainfall rate statistics for your location form ITU-R Rec. P.837. Then compute the specific attenuation using ITU-R Rec. P 838 and finally the path attenuation using ITU-R Rec P. 530. (All these Recommendations can be downloaded from http://www.itu.int/rec/R-REC-P/en )

Sumit, I agree with Bertram in all he said. You need a representative sample which will help you to at least make interseasonal comparisons. So, a year is a minimum. If you want to do just that. Scientifically, it will be hard to argue that only one year is representative, though. You need to be able to do interannual comparison to be able to provide trends. With the current changing patterns and amounts of precipitation everywhere in the world due t climate change, it becomes even harder to get a representative sample...But, half a solar cycle (5 years) or a solar cycle are good timeseries.

There are many ways you can do that. If you really do not have funding to support the purchase of a meteorological station, then, I suggest that you visit the NASA "GIOVANNI" meteorological portal at this URL:

http://disc.sci.gsfc.nasa.gov/giovanni/overview/index.html.

They have archival data going back 50 years. That will help you put your sample into the historical perspective and see how representative it might be. This portal also posts new datasets daily, which mean that if you have no funding, you still can get daily data. Dataseries can go down to hourly data rates in some cases. That's not the every-minute data points, but that can be a start.

In addition to that (because no matter what you do this URL will give you the historical perspective), if you have a little money, you can go to this URL:http://www.microdaq.com/occ/hws/index.php

These stations are wonderful, robust, and durable. It is a good investment. I use them in very difficult environmental conditions in the High Andes. If you have a little money, I'll put it in there. Best of luck!

Thank u ...................

If it is still topical...

One possibility is to estimate rain intensity via attenuation of mobile phone mast signals. The experiment was carried in the Neiherlands: http://www.bbc.co.uk/news/science-environment-21290976

Good information

Thanks for all

Actualy, i have a question:

what is the equation i have to use for calculte the annual rainfall rate?