Radio frequency (RF) harvesting is showed to be a feasible technique to power energy neutral devices, providing a flexible solution to exchange small amounts of energy. The rectifier, used to convert RF to direct current (DC), introduces non-linearities, degrading the efficiency of the RF harvester. Different techniques are studied in literature to address this challenge, e.g., by using high peak-to-average power ratio (PAPR) signals. This research presents several PySpice rectifier models to evaluate the efficiency of different signal waveforms and RF harvester architectures. In this work, these models are utilized to assess the energy-efficiency gain of high PAPR signals with respect to single tone signals. As resulted from this work, we concluded that the gains of high PAPR signals depend strongly on the rectifier circuit, even having an adverse effect in case of a voltage doubler.