New architecture for wireless implantable neural recording microsystems based on frequency-division multiplexing

This paper investigates the use of a new architecture for implantable microsystems for multi-channel intra-cortical neural recording. The proposed architecture performs frequency-division multiplexing (FDM) to wirelessly transfer multiple neural channels to an external setup. Based on the proposed idea, an 8-channel wireless neural recording system was designed. As a result of FDM, preconditioned neural signals are placed in the frequency domain with 100kHz spacing, occupying a ~800-kHz bandwidth starting from 10MHz. The entire band is then shifted to within the traditional frequency modulation (FM) band. The system, designed in a 0.18-μm standard CMOS process, consumes 4.7mW@1.8V.