Integrated UWB Transmitter and Antenna Design for Interfacing High-Density Brain Microprobes

This paper presents and compares two transmitter topologies (TX1 and TX2) using different modulation schemes to provide high data rate in high-density neural recording systems. Both transmitters use IR-UWB implemented based on an edge combining approach. TX2, which is using an improved topology, consumes less power and uses less area than TX1, while supporting the same data rate. The power consumption is also reduced by 35% at 500 Mbps in TX2. Both transmitters employ pulse shaping within the 3.1 and 7 GHz subband of the unregulated ultra-wide band to mitigate high transmission loss of the propagated EM waves above 7 GHz inside biological tissues. An implantable antenna and an external antenna are designed for utilization as TX and RX antennas in this application, respectively. Both transmitters have been fully integrated into a standard TSMC 0.18-mu m CMOS technology and provide high data transmission rate above 500 Mbps. TX1 supports OOK and binary phase shift keying (BPSK) modulations, while TX2 supports only OOK modulation.