Multi-frequency conditioning system of the inductive loop sensor — Simulation investigations

The concept of the multi-frequency conditioning system of the individual inductive loop sensor signal, with the separation of impedance components was presented in the hereby paper. Simulation investigations concerning dynamic states in the system excited by a step change of the sensor impedance parameters, were performed. The system behaviour in the presence of disturbances - induced in the sensor circuit - was also studied. The analysis of electromagnetic interferences generated by engines of vehicles was preliminarily performed. The simulation investigations confirm that the operation of the conditioning system - simultaneously - at two frequencies allows to obtain magnetic pairs of resistance and reactance profiles. This ensures that at least one pair of undisturbed signals will be obtained. This can ensure improvements of the operation reliability of the axles loop detection systems as well as the systems of measuring vehicle parameters in traffic.