imec presents a pioneering IEEE 802.15.4z compliant impulse radio (IR) ultra-wideband (UWB) transceiver for high-precision ranging. Building on a cost-efficient silicon implementation, imec’s transceiver chip accomplishes a 1.4mm ranging precision and comes with record low power consumption. As such, it paves the way for a variety of innovative (automotive) applications. One use case includes the creation of UWB radar-on-chip systems for in-cabin (child) presence detection, and driver monitoring.

IR-UWB technology is an enabler of multiple automotive, smart industry, smart home, and IoT use cases – thanks to its ranging and localization capabilities. It comes with the ability to locate assets in warehouses, hospitals, and factories with centimeter precision – and helps people navigate large spaces, like airports and shopping malls. One of IR-UWB’s main differentiators is that it largely outperforms narrowband technologies (such as Bluetooth) in terms of ranging precision. On the downside, it uses more complex and expensive circuits and typically exhibits higher power dissipation.

Fabricated in 28nm CMOS technology and occupying a silicon area of 1.33mm², imec’s 6 to 9GHz IEEE 802.15.4z compliant IR-UWB 3Rx-1Tx transceiver comes with a ranging precision down to 1.4mm. While this outperforms competitive approaches by several orders of magnitude, it does not come at the expense of a larger power budget – as the transceiver chip merely consumes 8.7mW/21mW in continuous Tx/Rx mode. It also meets UWB’s tight international spectral emission regulations with sufficient margin.

The chip’s record low power consumption results from a highly optimized, low-power, and interference-resilient Rx architecture, coupled with an innovative digital polar transmitter architecture. A distributed, two-stage all-digital PLL further reduces the chip’s power consumption and contributes to a reduced measurement time for localization. To improve its ranging performance (while complying with spectrum regulations), the system uses an analog finite impulse response (FIR)-based Tx pre-emphasis approach for more advanced, flexible pulse shaping.