Centralized Rainfall Estimation Using Carrier to Noise of Satellite Communication Links

Abstract

In this work, we present a centralized method for real-time rainfall estimation using Carrier-to-Noise power ratio (C/N) measurements from broadband satellite communication networks. The C/N data of both forward-link and returnlink are collected by the gateway station (GW) from the user terminals in the broadband satellite communication network and stored in a database. The C/N for such Ka-band scenarios is impaired mainly by the rainfall. Using signal processing and machine learning techniques, we develop an algorithm for realtime rainfall estimation. Extracting relevant features from C/N , we use artificial neural network in order to distinguish the rain events from dry events. We then determine the signal attenuation corresponding to the rain events and examine an empirical relationship between rainfall rate and signal attenuation. Experimental results are promising and prove the high potential of satellite communication links for real environment monitoring, particularly rainfall estimation.

Rainfall Estimation from Tropospheric Attenuation Affecting Satellite Links

“…A key step of the model consists in classifying rain events as stratiform or as convective, hence in deciding whether (8) or (10) should be used to calculate the rain height. In temperate regions (like in Italy), there is a clear prevalence of stratiform events during cold months, and of convective ones during warm/hot months.…”

“…The equivalent rain height is calculated while using (10) since the event occurred in April (m = 4): the variability of the precipitation is tracked with a significant degree of accuracy, leading to an estimate of the total rainfall accumulation that closely matches the measurements (see Figure 12). Figures 13 and 14 refer to a typical event in Autumn (November, = 11): in this case, the equivalent rain height is calculated while using (8). The model accuracy is lower than in the previous event, but the results are still quite satisfactory.…”

“…The model accuracy is lower than in the previous event, but the results are still quite satisfactory. Figures 13 and 14 refer to a typical event in Autumn (November, = 11): in this case, the equivalent rain height is calculated while using (8). The model accuracy is lower than in the previous event, but the results are still quite satisfactory.…”

“…As shown in (8) and (10), the equivalent rain height h R depends on the "instantaneous" value of the 0 • C isotherm height h 0 , which, as mentioned in Section 3.3, is extracted from the ERA5 database with a time resolution of an hour. Specifically, each sample of h 0 (t * ) is used in the model for the 60 min following t * .…”

“…The methodologies that are currently available to assess rainfall rate via satellite links are of limited accuracy and reliability and, in some cases, of complex implementation [8][9][10][11]: as a consequence, it becomes necessary to investigate alternative estimation methods, which only require few measurable physical parameters as input.…”