IJRECE VOL. 2 ISSUE 4 OCT-DEC 2014 ISSN: 2393-9028 (PRINT) | ISSN: 2348-2281 (ONLINE) INTERNATIONAL JOURNAL OF RESEARCH IN ELECTRONICS AND COMPUTER ENGINEERING A UNIT OF I2OR 6 | Page Review Paper on “Extraction of Information from Droplet Analysis using Signal Processing” Mr. Pandharinath A Ghonge 1 , Dr. Kushal R Tuckley 1 1 Electronics Engg. Department, Ramrao Adik Institue Technology Nerul Navi, Mumbai, India Abstract - The 2D-Video-Distrometer is a newly developed precipitation gauge, working on the basis of high defined video cameras. 2D Video-Distrometer is designed to meet the needs generally of anybody interested in details on precipitation. The rain consists of patches of elementary drop size distributions over a range of different scales. All measured drop size distributions that the interpretation of the measured distribution depends upon whether the rain is statistically homogeneous or not. It is argued and demonstrated using Monte Carlo simulations that in statistically homoge-neous rain, as the number of patch included increases; the observed spectrum of drop sizes approaches a “steady distribution. In contrast, steady distributions in statistically homogeneous rain are more amenable to deterministic interpretations since they depend upon factors independent of the measurement process. A snowflake is an aggregation of ice crystals. A non- aggregated snowflake often exhibits six fold radial sis fold radial symmetry. The distrometer is an instrument to measure the size, shape, velocity and precipitation of particles Keywords – 2D-Video-Distrometer, Patches, Snowflake. I. INTRODUCTION Knowledge on details of rainfall is of vital importance in meteorology, in the fields of signal processing, Various types of distrometers measure different parameters some of the interesting parameters and in many cases some have to be set to predefined values,. In this situation the idea of a new develop instrument has come up, the new instrument should measure all the relevant parameters and identify nature of rain. Now, The meaning of a drop size distribution is one of vital part[1] In the past, the measurement of drop sizes was a straightforward albeit very laborious task involving sifting raindrop pellets. By involving several studies to collect an impressive array of data in several straits form rain events of different intensities. The frequency distribution of drop sizes (diameters, volumes) that is characteristic of a given fall of rain. In convective clouds, the drop-size distribution is found to change with time and to vary systematically with height, the modal size increasing and the number decreasing with height [2] For many purposes a useful single parameter representing a given distribution is the volume median diameter, that is, that diameter for which the total volume of all drops having greater diameters is just equal to the total volume of all drops having smaller diameters. The drop- size distribution is one of the primary factors involved in determining the reflectivity of any fall of precipitation 2D-Video- Distrometer Originated in the area of weather radar and propagation research, the 2D-Video-Distrometer is now suited for all kinds of applications where details on precipitation are of interest [3] II. DROP DISTRIBUTION The meaning of a drop size distribution is one of the important parameter parameters that correlated with the rainfall rate, R . . Experiments [1] in which water was released to fall over long distances thereby allowing the distribution to evolve through drop breakup. While cumbersome and incomplete, since the water could never fall a distance sufficient for the drops to achieve “equilibrium,” such experiments were a convincing demonstration that the size distributions did indeed approximately evolve through drop breakup and coalescence toward those observed in nature. Moreover, the most advanced techniques combine different measurements using different instruments each having its own “beam width” so that, in effect, they are looking at different ensembles of rain patches, that is, at different total drop size distributions The required sufficient samples can be defined In order to see how the net distribution changes with increasing sampling (volume), these samples are then combined one by one and the resulting fraction of the total number of observed drops is calculated and plotted for the different drop sizes [1] In spite of increases in the total volume sampled, at no time do the contributions at any of the sizes become “steady.” At first with increasing distance the maxi - mum in the fractional contribution peaks at increasing sizes (solid line). The contributions from the larger drops then decrease while at still greater distances (sampling path lengths) there is a subsequent resurgence in the fractional contributions at the smaller sizes to the right of the dashed line*.This can be seen as well by looking at some selected size distributions [1,2] III. SAMPLE THRESHOLD A Poisson process is characterized by three assumptions that the probability of detecting more than one drop in a given volume that drop counts in nonoverlapping volumes are statistically independent random variables (at any length scale) that process is statistically homogeneous. With regard