Ultra-Low-Power Wireless Communication Using IR-UWB

The connection of our daily life’s objects to the cloud according to the Internet-of- Things (IoT) vision is about to revolutionize the way to live. To enable this revolution, a massive deployment of sensor nodes is required with predictions announcing up to trillions of these nodes. Such a massive deployment is not environmentally and economically sustainable with current technologies. Some of the pitfalls lay in the wireless communications of IoT nodes whose power consumption needs to be optimized in order to enable operation on ambient energy harvesting without compromising the connectivity. Recent wireless solutions usually tackle the energy problem with low-duty cycled radios taking advantage of the ultra-low requirement on speed by the sensing application. However, key applications using audio/vision sensing or requiring low latency call for high data rates. Impulse-Radio Ultra-Wideband (IR-UWB) is considered as a promising solution for high data-rate, short range and low-power solution due to the duty-cycled nature of the signal as well as the potential for low-complexity and low-power transmitter (TX) architectures. These characteristics have been the driving force behind the development of the IEEE 802.15.4a standard covering data rates from 0.11 to 27.24Mbps. A mostly-digital UWB transmitter System-on-Chip (SoC) which was designed for ultra-low voltage in 28nm FDSOI CMOS compliant with the IEEE 802.15.4a standard.

Another connectivity challenge comes from the massive deployment of IoT nodes. To avoid the congestion of the RF spectrum, cognitive communications based on software- defined reconfigurable radio (SDR) architectures covering bands up to 6 GHz are needed for agile wireless communications. On the receiver (RX) side, these radios impose though requirement on the low-noise amplifier (LNA) over a wide frequency range. Reducing the supply voltage pushes devices from strong inversion to moderate inversion and that forward back biasing can be used to mitigate this trend and increase the design space. The impact of technology scaling on important RF figures of merit to highlight the ability of advanced 28nm FDSOI CMOS to trade speed for power. Then illustrate this ability at circuit level by looking at the optimum sizing of a noise cancelling ultra-low-voltage wideband LNA targeting the hot topic of SDR.

This talk will introduce the IR-UWB, SDR technology with use cases for IoT. The characteristics of the communication with potential for IR-UWB and SDRs will be explored.