The Transponder Data Recorder: final implementation and former results

The Transponder Data Recorder (TDR), equipment implemented for research purposes at Tor Vergata University, is a designed to receive and to record signals emitted by airborne and vehicular transponders at 1090 MHz (Mode S replies and 1090 ES signals). The prototypal version of the TDR, a mono-channel device, was presented at the ESAV’11 conference in Capri (Italy). Such a prototype has been used to evaluate the design and to define the final version of the TDR. The latter is composed by a uniform linear array with six special wide-band patch elements, five receiving channels (four linear and one logarithmic) and a programmable digital section. Presently the antenna system is placed on the top of the engineering building of Tor Vergata University, in the neighbors of Rome, Italy. The system is used to analyze and record the 1090 MHz channel radio load and to test signal processing algorithms on real signals. Thanks to the cooperation by the Era Company (Czech Republic), the TDR is used in conjunction with two Squid (i.e. Era squitter beacons). The activity goal is to evaluate the performance of vehicular surveillance in an airport area characterized by several 1090 MHz signals sources and a significant multipath scenario.