A Network of Portable, Low-Cost, X-Band Radars

Radar is a unique tool to get an overview on the weather situation, given its high spatio- temporal resolution. Over 60 years, researchers have been investigating ways for obtaining the best use of radar. As a result we often find assurances on how much radar is a useful tool, and it is! After this initial statement, however, regularly comes a long list on how to increase the accuracy of radar or in what direction to move for improving it. Perhaps we should rather ask: is the resulting data good enough for our application? The answers are often more complicated than desired. At first, some people expect miracles. Then, when their wishes are disappointed, they discard radar as a tool: both attitudes are wrong; radar is a unique tool to obtain an excellent overview on what is happening: when and where it is happening. At short ranges, we may even get good quantitative data. But at longer ranges it may be impossible to obtain the desired precision, e.g. the precision needed to alert people living in small catchments in mountainous terrain. We would have to set the critical limit for an alert so low that this limit would lead to an unacceptable rate of false alarm

Housing Policy in the Political Agenda: The Trajectory of Portugal

Housing policy, a field located at the junction between welfare and spatial planning, is a key component of urban agendas. This chapter refers to the trajectory of housing policy in Portugal exploring how, and to what extent, housing has constituted a growing matter of political attention, in a country that—formally—has no urban agenda, but where significant interventions in the housing sector have occurred in recent times. We explore how housing policy has changed over the last four decades by adopting a multi-scalar perspective on the governance of the housing sector, in order to show how many different actors (central and local governments, policy experts, activists, etc.) and contingent events (such as the post-2008 economic crisis or the COVID-19 pandemic, whose full impact on housing policy is already evident but still difficult to grasp) have influenced these dynamics. This chapter proposes a genealogy of the emergence of the idea of “housing policy” as a matter of political attention in its own right and its status as a component in the country’s urban agenda. A key focus of the analysis will be the relationship that has developed between Portugal and the EU—from the country’s adhesion to the European Economic Community (1986) to the programme Next Generation EU (2020).info:eu-repo/semantics/publishedVersio

Hail Sensing Probes: Feasibility Analysis for Probes to Monitor and Study Hail

This work presents the feasibility study regarding the realization of hail sensing probes for remote sensing and study of hail. The probes are designed as artificial hailstones in order to study both the physical properties of the portion of atmosphere where the formation of hail occurs and the modification of atmospheric conditions while the hailstones are falling to the ground. The basic idea is to realize sensors with a similar fluid-dynamic behavior with respect to hailstones; the density, the weight and the size of the probes are determined. Consequently, the specification of the electronic boards, sensors, and material to realize the probes are studied and presented. The hail sensing probes can be dropped by a plane, or potentially a UAV (Unmanned Aircraft Vehicle), which fly above and through the clouds where the hail formation occurs. During their falling to the ground, the sensors installed on the probe measure directly different parameters such as humidity, temperature, pressure, acceleration. All data are sent to a receiver located on the ground. The study of the sampling frequency of each sensor is presented, together with the analysis of the propagation channel, in order to assure a robust communication link between probes and the ground receiver. The energy balance is also computed. The work demonstrates that a set of this kind of disposable sensors can be realized. They can be used for efficient monitoring operations and studies of hail formation dynamics and conditions, thus increasing the set of instruments for the monitoring and remote sensing of hail

A SURVEY ON DEVICES EXPLOITING LORA COMMUNICATION

Information and Communication Technologies (ICT) have experienced a large application in many fields, such as smart homes, health monitoring, environmental monitoring, and a great number of studies is present in literature. In particular, it is expected that the Internet of Things (IoT) will become increasingly pervasive in everyday life. Among different technologies, devices based on Long Range (LoRa) and LoRaWAN stand out due to their relative low cost, low power consumption and large cover range. In this survey, recent papers investigating applications of LoRa modules have been selected. The different usecases are presented with a comparison between communication parameters and results obtained

A Wireless Sensor Network Ad-Hoc Designed as Anti-Theft Alarm System for Photovoltaic Panels

Photovoltaic (PV) systems have attracted increasing attention in last years as well as Wireless Sensor Networks (WSNs), which have been used in many application fields. In PV plants, especially in ground installations, a lot of thefts and damages occur due to the still high cost of the modules. A new experimental WSN ad-hoc has been designed to be an anti-theft alarm system. Each node of the network is directly installed under each PV string and it is equipped with an accelerometer sensor capable to detect a minimum displacement of the panel from its steady position. The WSN presents a star topology: a master node cyclically interrogates the slave nodes through RF link. It collects all the nodes responses and communicates though a RS-232 interface with a control PC checking the network status. When a slave node detects an alarm, continuous messages are sent to the control PC which turns on all the alarm signaling systems. The control PC is equipped with an open source operative system and software and provides for SMS, e-mail and sound-light signaling in case of alarm. It also communicates with a remote server where all the WSN information is stored. A first low cost experimental WSN has been already installed and it is working properl

Developing a low cost multipurpose X-band FMICW radar

FMCW radar, X-band, multipurpose radar, low cost, atmospheric monitoring, target detection, radar altimete

Localization of RFID tags for environmental monitoring using UAV

The paper presents the experimental implementation of a method to localize RFID tags in an outdoor environment using UAV. During the installation phase, it is possible to measure the coordinates of the installation point using a topographic GNSS receiver. The tags positions can evolve with time and after a specific desired period of time (e. g. 1 month or 1 year) it is necessary to relocate them. This can be done estimating the distance between the tags and a UAV, exploiting the measurements of the Received Signal Strength Indicator (RSSI). The tags are placed over an outdoor test area and a large amount of RSSI measurements are made in different position, well distributed in space, using a UAV equipped with a specific tag reader. On such data, a multilateration-based localization algorithm is applied achieving good results. The description of RFID tags is reported together with the localization algorithm, the test description and the preliminary results

ON THE REALIZATION OF A COMMUNICATION SYSTEM FOR ATMOSPHERIC PROBES BASED ON LORA TECHNOLOGIES: PRELIMINARY MEASUREMENTS AND RESULTS

Characterization of atmospheric properties remains a latent ambiguity for weather forecasting and climate models since their characteristics depends on multidisciplinary processes in a wide range of natural scales. The development of ultra-small light disposable radio probes is important to understand this properties Being light-weighted, the probes will have a fluiddifferent atmospheric layers after been released, thus simulating the behaviour of small particles (e.g. drops). Each disposable probe is equipped with compact size microprocessors (presently the first prototype uses velocity, acceleration, pressure, temperature). The probes collect, store and then send the coded information to a base station located at the ground through a dedicated radio transmission link. It is to be noted that longrange communication link (10 km) should be assured with low power consumption technology: a network -modules and the base station is the potential adopted solution. In order to realize the communication system for the atmospheric probes, some prototypal links and networks have bene realized using the Adafruit Feather 32u4 LoRa Radio RFM95 modules. It is an embedded module, which contains a LoRa transceiver RFM95 and an ATmega32u4 microcontroller. The radio module can be powered using 3.3 volts either by using a micro USB or an external battery and it can transmit from +5 dBm to +20 dBm, which are theoretically enough for the purpose of this study. The present work presents the preliminary measurements made both in indoor and outdoor environment considering differ find the best set of parameters to work in the harsh environment to acquire information about warm clouds and send them to the ground receiver. Particularly detailed measurements have been made in harsh environmental found inside a warm cloud. The measurements techniques and results are presented together with the realization of a first operational prototype of both probes and ground receiver