HR: 0800h
AN: P11B-0548    [Abstracts]
TI: The Italian Radio Echo Sounding System : Improvement Solutions.
AU: * Zirizzotti, A
EM: zirizzotti@ingv.it
AF: Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, Roma, 00143, Italy
AU: Baskaradas, J
AF: Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, Roma, 00143, Italy
AU: Bianchi, C
AF: Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, Roma, 00143, Italy
AU: Sciacca, U
AF: Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, Roma, 00143, Italy
AU: Tabacco, I
AF: Università di Milano, Dipartimento di Scienza della Terra, Sezione Geofisica, Via Cicognara 7, Milano, 20100, Italy
AU: Zuccheretti, E
AF: Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, Roma, 00143, Italy
AB: Radio Echo Sounding (RES) system are widely used RADAR systems in glaciology, to obtain information on the level of the bedrock, the ice thickness and its inhomogeneties, i.e. the internal layering of glaciers and subglacial lake exploration. Since, 1997 the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in Italy was involved in the development of the airborne radio echo sounding system (Glacio RADAR) which is continuously upgraded. This radar was used in several Italian Antarctic Expeditions (1997, 1999, 2001 and 2003). The Glacio RADAR mounted on an aircraft flies at an altitude around 300m above the ice surface during the survey. The first model operates at 60 MHz with a pulse width variable between 0.3μs and 1μs. Two wired folded dipole antennas were mounted beneath the aircraft wings; one for transmission and the other for receiving. The listening time is 64μs which implies a maximum penetration depth (range) in the ice of about 5.3 km. The horizontal sampling rate is 10 traces/s at a mean aircraft speed of about 70 m/s. This would produce roughly 143 traces per kilometre (horizontal resolution of 1 trace every 7 m). The Navigation and geographical information is based on a GPS receiver on board giving longitude, latitude, altitude and time for the acquired radar trace. In this presentation two enhanced RES systems developed by INGV are described. These systems, with a new carrier signal (phased coded), operates at 150 MHz and 300 MHZ with a new antenna system (8 folded dipoles) and with the implementation of powerful signal processing techniques to increase signal to noise ratio. Amplitude information is used to recognise the electromagnetic characteristics of the reflector. This new RADAR will improve horizontal and vertical resolutions in the ice with a capability to discriminate the internal layers (less than 1m) obtaining the measure of the ice accumulation rate through the knowledge of the depth of the known isochronal horizons.
DE: 0738 Ice (1863)
DE: 0758 Remote sensing
DE: 0760 Engineering
DE: 0776 Glaciology (1621, 1827, 1863)
DE: 0794 Instruments and techniques
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting