Based on the alternating direction implicit (ADI) procedure, the complex envelope (CE) method, and the higher order (HO) concept, an unconditionally stable performance-enhanced convolutional perfectly matched layer (CPML) is proposed to efficiently simulate bandpass electromagnetic (EM) devices and signals in the finite-difference time-domain (FDTD) lattice. Through the numerical example, the proposed scheme shows the advantages of the unconditionally stable ADI procedure, HO-CPML scheme, and CE method in terms of absorbing performance, computational efficiency, and bandpass EM simulation.