Wireless interfacing to cortical neural recording implants using 4-FSK modulation scheme

This paper used a 4-level Frequency Shift Keying (4-FSK) modulation scheme to enhance the density of wireless data transfer from implantable biomedical microsystems to the outside world. Modeling and simulation of the wireless channel for 4-FSK modulation in the case of a neural recording implant has been done. To realize the 4-FSK scheme, the modulator and demodulator circuits are proposed, designed and simulated in a 0.18-μm CMOS process, and in the 174–216 MHz frequency band at a data rate of 13.5 Mbps. Operated using a 1.8 V supply voltage, the modulator circuit consumes a power of 7.8 μW.