High-Frequency Memristor-Based BFSK and 8-QAM Demodulators

This paper presents developed memristor-based demodulators for 8 circular Quadrature Amplitude Modulation (8-QAM) and Binary Frequency Shift Keying (BFSK) operating at 25MHz. In our implementations, the experimental-based `nonlinear' dopant drift model is adopted for all the proposed circuits which incorporates all known nonidealities of practically realized memristor devices and achieves high frequency of operation. The suggested designs leverage the distinctive characteristics of the memristor device, which is the variation of average memristance versus the frequency, phase, and amplitude of the periodic excitation input. The proposed demodulators feature small integration area, low power consumption, and easy implementation. Moreover, the proposed QAM demodulator precludes the requirement for the carrier recovery circuits. In doing so, the designs were validated by transient simulations using the nonlinear dopant drift memristor model. The simulations results show high agreement with the theory presented.