Investigation of meteor altitude distributions with the EISCAT incoherent scatter radars

Investigation of meteor head echoes and their properties by High Power Large Aperture radars is one of the important issues in the ionospheric research. The EISCAT radars have been among the leading ones to study the head echoes partly due the dual-frequency capability provided with the co- located 930 MHz UHF and 224 MHz VHF radars in Tromsø, Norway and 500 MHz EISCAT Svalbard Radar (ESR). All these radars run regularly open access Common Programs (CP). This project work contains general description of the EISCAT radars and special attention has been devoted the CP-6 modes. Literature survey of the current research by other radar systems was done. The head echo meteor observations by EISCAT radar systems have been regularly run since 1990. The observations provided information on altitude distributions and target sizes. These parameters have been implemented to the head echo model for EISCAT systems. The aim of this work was to produce meteor head echo altitude distributions from the large data set that have been collected during CP-6 observation campaigns in 2005 and 2006. A special routine to search for meteor echoes and their identification in CP- 6 data formats has been written. The final result of the work is the altitude distributions of the UHF, ESR and VHF head echoes from a total of about 340 hours existing CP-6 data. The cutoff heights registrations of the altitude distributions are in good agreement with previous investigations of altitude distributions at EISCAT. From the analysis of the meteor detections follows EISCAT radars observed sporadic meteors. It was shown that EISCAT system is capable to detect high altitude meteors. A comparison of the present data to earlier EISCAT results shows that the solar cycle might have an additional effect on the head echo ceiling effect.Validerat; 20101217 (root