A Fully Integrated Programmable 6.0–8.5-GHz UWB IR Transmitter Front-End for Energy-Harvesting Devices Tuomas Haapala , Student Member , IEEE, Tuomas Rantataro, and Kari A. I. Halonen, Member , IEEE

Abstract

Ultra-wideband impulse radio transceivers are becoming a key building block for establishing ultralow power wireless sensor networks. However, impulse radio transmitters commonly suffer from a low spectral quality and a coarse frequency tuning resolution, which limits their global applica- bility. In this article, we present a fully integrated ultralow power impulse radio transmitter front-end (TFE) whose pulse shaping capabilities and integrated output matching network make it globally applicable up to a 4-MHz pulse repetition rate. We demonstrate a digital carrier frequency-tuning method that achieves a 28-MHz resolution over the frequency band of 6.0–8.5 GHz. In addition, we show that the temperature dependence of the TFE’s carrier frequency can be compensated digitally over the industrial temperature range from −40 ◦Ct o 85 ◦C. The proposed TFE supports energy-harvesting appli- cations particularly well due to its low leakage power level of 380 nW and a high tolerance to power supply transients during pulse generation. It is demonstrated to operate robustly with low-drive regulators powered by low-quality sources. The TFE is fabricated in a 65-nm CMOS process. It generates 1.8-pJ pulses at a 7.5-GHz carrier frequency while consuming 63 pJ per pulse, corresponding to 2.3% efficiency.