This paper discusses the design of a broadband wireless network infrastructure which itself is a rain measurement platform for applications such as disaster alarm and sudden hazard decision management systems. A sensor testbed is setup which consists of a hybrid broadband wireless network in conjunction with real-time acoustic rain rate point sensors and complementary rain gauges. The testbed simulates the commercial deployment of a line-of-sight wireless backbone (implemented via a 26 GHz line of sight link) and broadband wireless access network at 5 GHz and 2.4 GHz. Combined wireless signal fade, acoustic power and tipping bucket rain rate measurements over a several month span indicate the feasibility of using rain-induced attenuation and fade durations to trigger imminent-hazard alerts.

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We present the first results of a nationwide experiment that uses 5GHz fixed wireless network as a rain alarm system through monitoring the changes in received signal levels. This paper proposes an alternative framework and correlation approach for rain sensing, which rely mainly on the attenuation from broadband wireless systems. Unique to this system is an automatic reporting of received signal levels coming from a central location that gathers data of one-minute resolution from SmartBro subscribers. The SmartBro wireless system is one of the largest deployments in the world composed of 5 GHz links, which may help in reinforcing rain data collection due to their ubiquity of deployment in the Philippines, with nearly 20,000 land-based antennas. To demonstrate this capability, we selected eastern seaboard cities near the Pacific Ocean with fixed wireless subscribers virtually at random, and studied the changes from baseline attenuation during strong rain events. The reckoning method comprises of (1) baselining method to determine signal loss in normal weather condition, (2) sigma scheme technique that uses the variation of the signal in order to determine rain presence. Lastly, we also made a visualization tool for highly intense precipitation events. Time series videos of signal loss in the Philippines, with plotted location-specific signal loss data were developed for key meteorological events in the past two years: of which include the Southwest Monsoon season in 2012 and the devastation of Typhoon Haiyan in 2013.

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This paper presents the recent results of the design of a novel acoustic rainfall sensing system that is low-cost, portable, and easily deployable, which makes use of the recorded sound produced by the impact of the raindrops on the sensor surface. The sensor design allows the gathering of acoustic signal power and sending it to a server after a specified time interval, either through SMS or mobile internet connection. It exists in a weather-proof, standard-conformant, standalone system with its own power supply and telemetric capabilities. These acoustic point sensors can gather rainfall data at high spatial and temporal resolutions. Such deployments can show the variations of rainfall intensities in sub-kilometer areas, particularly in the tropical regions. Since it is low-cost, it can also improve the density of rainfall measuring devices in an area. Moreover, the reliability is improved by providing near-real time data, as opposed to tipping buckets with manual data retrieval. The prototype sensor system was placed next to standard rain measuring devices and observed during the rainy season. The paper will discuss the design and deployment of the system, as well as initial results of data analysis and comparison with standard rain measuring devices.