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The chosen transmitters are the Belgium dourbes beacon (BRAMS)operating at 49.970 MHz and another
dedicated meteor radar transmitter based at Juliusruh in Germany (Institute Atomospheric Physics) operating at 53.500 MHz.
Meteor radio signature traces depict high frequency ranges shown in yellow before rapidly dropping to the
radar carrier frequency in blue as the meteoroid decelerates in the atmosphere. The ionisation increases
in this phase that inturn strengthens the radio signal as it burns up. The captured Leonid radio signatures
trace examples given below portray the event over time of the meteors furious entry phase in the upper
Earth atmosphere approximatley 90 km high.
Plasma ionisation occures both at the meteor head and tail. This allows reflection of radio waves by a suitable radio transmitter to be captured by a radio receiver. Using a computer or laptop the meteor radio spectrograms can be recorded and then anaylised by suitabe radio software (Spectrum Labs). This ineffect preserves the meteroids dynamic path and stages of its disintergration and demise through the upper atmosphere that effect its radio reflection cababilities. The received signal strength,and deviation of the tuned
ICY SCIENCE | WINTER 2013- 2014