Smartphone-Based Experimental Analysis of Rainfall Effects on LTE Signal Indicators.

Area of Science:

• Environmental Science
• Telecommunications Engineering
• Signal Processing

Background:

• Existing research on radio propagation often assumes line-of-sight (LoS) conditions, particularly for microwave frequencies.
• The influence of adverse weather, specifically rainfall, on non-line-of-sight (NLoS) cellular communication links remains less explored.
• Smartphone-collected data offers a scalable and ubiquitous source for studying real-world signal propagation phenomena.

Purpose of the Study:

• To investigate the impact of rainfall on cellular communication signal metrics under non-line-of-sight (NLoS) conditions.
• To analyze both small-scale and large-scale signal variations during dry and rainy periods across diverse geographical locations.
• To explore the potential of utilizing mobile phone signals for indirect rainfall detection.

Main Methods:

• Collection and statistical analysis of cellular signal measurements from smartphones across different locations and time windows.
• Examination of signal variations during dry versus rainy days, focusing on key metrics like reference signal received quality (RSRQ).
• Application of spectral analysis to identify changes in signal characteristics attributable to rainfall events.

Main Results:

• Consistent daily fluctuation patterns were observed in key cellular metrics, such as reference signal received quality (RSRQ), during rainfall.
• Spectral features of mobile communication metrics exhibited noticeable alterations during rainfall events.
• These rainfall-induced signal changes were found to be consistent across three distinct geographical locations.

Conclusions:

• Rainfall significantly impacts the performance and characteristics of everyday cellular communication links, even in non-line-of-sight scenarios.
• The observed signal variations provide evidence that by-product signals from mobile phones can be effectively leveraged for innovative rainfall-sensing applications.
• This research opens new avenues for low-cost, widespread environmental monitoring using existing mobile infrastructure.