A 16.4pJ/bit Fully Integrated IR-UWB Transmitter with PSK+PPM Modulation and On-Chip Antenna

This paper presents a fully integrated Impulse Radio Ultra-Wideband (IR-UWB) wireless transmitter (TX) chip with high transmission efficiency and on-chip antenna for brain-computer interface (BCI) application. A hybrid modulation method combining Pulse Phase Shift Keying (PSK) and Pulse Position Modulation (PPM) is proposed to boost the data transmission efficiency. An on-chip antenna is adopted to eliminate the external bulky UWB antenna thus minimizing the dimension of the whole BCI implant. This chip is designed and implemented using SMIC 180 nm standard CMOS process, with a core area of approximately 1.02 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>. The measurement shows that a 30 Mb/s data stream can be transmitted over a distance of 2 cm through the proposed antenna, with 16.4 pJ/bit energy efficiency and 491 μW power consumption.