Ultra-wide-band transmitter for low-power wireless body area networks: design and evaluation

TLDR

Wireless body area networks demand ultra‑low power radios, and ultra‑wide‑band technology offers advantages such as low‑complexity transmitters, receiver‑centric design, and duty‑cycled operation that can meet sub‑100 µW energy budgets. This work proposes a fully integrated low‑power UWB transmitter fabricated in standard CMOS. The design incorporates a compact pulse generator and is evaluated against state‑of‑the‑art narrow‑band solutions using a WBAN channel model. Measurements demonstrate that the integrated UWB transmitter achieves low power and cost, outperforming narrow‑band counterparts in short‑range scenarios due to reduced baseline consumption.

Abstract

The successful realization of a wireless body area network (WBAN) requires innovative solutions to meet the energy consumption budget of the autonomous sensor nodes. The radio interface is a major challenge, since its power consumption must be reduced below 100 /spl mu/W (energy scavenging limit). The emerging ultra-wide-band (UWB) technology shows strong advantages in reaching this target. First, most of the complexity of an UWB system is in the receiver, which is a perfect scenario in the WBAN context. Second, the very little hardware complexity of a UWB transmitter offers the potential for low-cost and highly integrated solutions. Finally, in a pulse-based UWB scheme, the transmitter can be duty-cycled at the pulse rate, thereby reducing the baseline power consumption. We present a low-power UWB transmitter that can be fully integrated in standard CMOS technology. Measured performances of a fully integrated pulse generator are provided, showing the potential of UWB for low power and low cost implementations. Finally, using a WBAN channel model, we present a comparison between our UWB solution and state-of-the-art low-power narrow-band implementations. This paper shows that UWB performs better in the short range due to a reduced baseline power consumption.