@article{f5ab338b0fa84c4c8b921aa83fceacbf,
title = "A delay spread cancelling waveform characterizer for RF power amplifiers",
abstract = "A two channel 65 nm CMOS RF-waveform characterizer is presented that enables multi-harmonic Adaptive Matching Networks (AMN) or Adaptive Digital Pre-Distortion (ADPD) in RF-power amplifiers. The characterizer measures the DC component and the first 3 harmonics of RF signals by applying a DFT to 8 (ideally) equally spaced quasi-DC output voltages. Conventionally in these types of systems accuracy is limited by sample timing accuracies, which in our case are mainly due to delay cell mismatch. We introduce a novel way to cancel delay cell mismatch, that significantly increases measurement accuracy at the cost of only a small power and area increase. The RF-waveform characterizer achieves 6.8-bit measurement linearity together with a (clock feedthrough limited) 24 dB SFDR. The measured power consumption for our proof-of-principle demonstrator is 18.6 mW at a maximum input signal frequency of 1.1 GHz under continuous operation. ",
keywords = "Discrete Fourier transform (DFT), Signal sampling, Power amplifiers, Signal characterization, Delay spread cancellation, CMOS integrated circuits",
author = "Maikel Huiskamp and Annema, {Anne J.} and Bram Nauta",
year = "2018",
month = dec,
day = "1",
doi = "10.1109/TCSII.2018.2873835",
language = "English",
volume = "65",
pages = "1834--1838",
journal = "IEEE transactions on circuits and systems II: express briefs",
issn = "1549-7747",
publisher = "IEEE",
number = "12",
}