Some articles on rain theory.

https://www.researchgate.net/publication/202846649_Single-drop_fragmentation_determines_size_distribution_of_raindrops

http://www.eurekalert.org/pub_releases/2013-02/giot-tro021513.php

http://physics.aps.org/story/v11/st2

http://phys.org/news/2011-10-birth-cloud-droplet.html

https://www.researchgate.net/publication/241064026_Droplet_nucleation_Physically-based_parameterizations_and_comparative_evaluation

Regards,

Joachim (not an expert)

Article Single-drop fragmentation determines size distribution of raindrops

Article Droplet nucleation: Physically-based parameterizations and c...

hello sidarth, rain attenuation is attenuation in signals caused by rain , mainly at microwave frequency at higher frequencies (mostly >8GHz) where as rain size distribution is general term used to categorized the rain drop.

u can find a lot of literature on both. basically for Nigeria and Malyasia. there is a lot of data available on net.

if u can the download (Journal of Atmospheric science : "Raindrop Size distribution & Sampling size errors" atuthor for this research paper is J.Joss & A.Waldvodge")

mainly thereare two way to calculate rain attenuation . physical and empirical .

if u want to calculate attenuation then u can use exponential law....

You can ask the question in different way, what is the relationship between the rainfall rate and the drop size distribution. You can use marshal palmer model to get the relationship, then you can calculate the rain attenuation VS rainfall rate to observe what is going on.