In this study, by simulating the wave-particle interactions, we show that sub-relativistic/relativistic electron microbursts form the high-energy tail of pulsating aurora (PsA). Whistler-mode chorus waves that propagate along the magnetic field lines at high latitudes cause precipitation bursts of electrons with a wide energy range from a few keV (PsA) to several MeV (relativistic microbursts). The rising tone elements of chorus waves cause individual microbursts of sub-relativistic/relativistic electrons and the internal modulation of PsA with a frequency of a few Hz. The chorus bursts for a few seconds cause the microburst trains of sub-relativistic/relativistic electrons and the main pulsations of PsA. Our simulation studies demonstrate that both PsA and relativistic electron microbursts originate simultaneously from pitch angle scattering by chorus wave-particle interactions.