%0 Journal Article
%T Multimode/Multifrequency Low Frequency Airborne Radar Design
%A Sandra Costanzo
%A Giuseppe Di Massa
%A Antonio Costanzo
%A Antonio Borgia
%A Claudio Papa
%A Giovanni Alberti
%A Giuseppe Salzillo
%A Gianfranco Palmese
%A Dario Califano
%A Luca Ciofanello
%A Maria Daniele
%A Claudia Facchinetti
%A Francesco Longo
%A Roberto Formaro
%J Journal of Electrical and Computer Engineering
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/857530
%X This work deals with the design of multimode/multifrequency airborne radar suitable for imaging and subsurface sounding. The system operates at relatively low frequencies in the band ranging from VHF to UHF. It is able to work in two different modalities: (i) nadir-looking sounder in the VHF band (163£¿MHz) and (ii) side-looking imager (SAR) in the UHF band with two channels at 450£¿MHz and 860£¿MHz. The radar has been completely designed by CO.Ri.S.T.A. for what concerns the RF and the electronic aspect, and by the University of Calabria for what concerns the design, realization, and test of SAR antennas. The radar has been installed on a civil helicopter and its operation has been validated in flight in both sounder and imager modality. Preliminary surveys have been carried out over different areas of Campania region, South Italy. 1. Introduction In recent years, great interest has been devoted to the development of airborne radars working in the frequency range from VHF to UHF bands (e.g., see [1¨C4]). The combination of low frequencies with high relative bandwidth of such systems allows several military and civilian applications. According to Table 1, these range from forestry applications, biomass measuring, and monitoring, archaeological and geological exploration, glaciers investigation, and detection and localization of buried targets. In addition, their extension to noncivil applications concerns subsurface target detection and foliage penetration. The development of this type of systems entails technological and scientific efforts in the design of antennas, low noise amplifiers, band-pass filters, and digital receiver technology, as well as in the field of data-processing algorithms. Table 1: Applications for low frequency airborne radars. In this framework, the Italian Space Agency (ASI) has promoted the development of a new multifunction/multimode airborne radar able to operate as a nadir-looking sounder in the VHF band and as side-looking imager in the UHF band. On one side, it constitutes a ¡°proof of concept¡± for next Earth observation and planetary exploration space missions; from another perspective, the system can be seen as a validation tool for civil and non-low frequency radar terrestrial diagnostics, imaging, and monitoring applications. The radar system has been conceived and funded by ASI to be a growing laboratory to experiment and asses potentialities of low frequency radar bands (up to about 1£¿GHz). To this aim, three working frequency values have been chosen, namely, low, middle, and high ones. The low one (163£¿MHz), up to now,
%U http://www.hindawi.com/journals/jece/2013/857530/