Estimating electrical parameters of a track circuit including a transmitter, a receiver, and a track section between the transmitter and receiver. The transmitter outputs, over the track section towards the receiver, a signal including a data packet part, and the signal received by the receiver is decoded to determine the data packet received. Simulated signals are generated, via a predetermined software model including parameters of the track circuit, by varying an actual value input for the model parameters, each signal generated corresponding to actual values input for the parameters. Each simulated signal is compared with the signal received at a receiver until finding a part of a simulated signal that matches a corresponding part of the signal received at a receiver. The actual parameter values corresponding to the simulated signal that match the signal received at the receiver are estimated as the actual parameters of the track circuit.