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Shen, Y. (author), Bootsman, R.J. (author), Alavi, S.M. (author), de Vreede, L.C.N. (author)This article presents a wideband 2× 12 -bit direct-digital RF modulator (DDRM) operating in a 0.5-to-3-GHz band for 5G transmitters. The proposed digital Cartesian modulator features an advanced IQ-mapping technique to boost RF power by 3 dB and suppress the I/Q image. To verify the proposed concept, a 40-nm CMOS prototype is implemented...journal article 2022
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Mortazavi, S.M. (author), Shen, Y. (author), Mul, D.P.N. (author), de Vreede, L.C.N. (author), Spirito, M. (author), Babaie, M. (author)This article presents an efficient digital polar transmitter (DPTX) at mm-wave frequencies that exploit a novel N -way series Doherty combiner (SDC) to enhance its drain and system efficiency at deep power back-off (PBO). The proposed N -way SDC is scalable and can be implemented elegantly using N transformers and N-1 shunt capacitors. As a...journal article 2022
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Beikmirza, M.R. (author), Shen, Y. (author), de Vreede, L.C.N. (author), Alavi, S.M. (author)To support wideband complex modulated signals and comply with the stringent requirements of modern communication standards in an energy-efficient manner, recently, digital transmitters (DTXs) have been explored to fully benefit from the high-speed switching and integration capabilities of nanoscale CMOS technologies [1]–[5]. These DTXs are...conference paper 2022
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Montazerolghaem, M.A. (author), Pires, Sergio (author), de Vreede, L.C.N. (author), Babaie, M. (author)The introduction of the fifth-generation (5G) New Radio (NR) standard has imposed several challenges in the design of sub-6GHz receivers (RX). Firstly, the maximum channel bandwidth(2BW) increases to 100MHz, while a -15dBm continuous-wave (CW) blocker can be located only \Delta f=85MHz away from the desired band edge. Such a small \Delta f/BW...conference paper 2021
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Pashaeifar, M. (author), de Vreede, L.C.N. (author), Alavi, S.M. (author)This article presents a wideband energy-efficient transmitter (TX) for 5G mm-wave phased-array systems. It features an advanced double-quadrature direct upconverter (DQ-DUC) to improve its in-band linearity and spectral purity. The proposed TX architecture incorporates an efficiency-enhanced balanced power amplifier (EEBPA) that mitigates...journal article 2021
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Beikmirza, M.R. (author), Shen, Y. (author), de Vreede, L.C.N. (author), Alavi, S.M. (author)We present a wideband, 12-bit four-way Doherty Cartesian digital transmitter (DTX) featuring an innovative 50%-LO signed I/Q interleaved up-conversion technique that enables close to perfect orthogonal I/Q summation. The DTX incorporates a compact four-way lumped-element Doherty power combining network to enhance its average efficiency at...journal article 2021
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Feng, Y.J. (author), Beikmirza, M.R. (author), Mehrpoo, M. (author), de Vreede, L.C.N. (author), Alavi, S.M. (author)We present a wireline transmitter (TX) for re-configurable chip-to-chip links. The proposed design features a frequency-adaptive clock chain, a fast 16:1 clocked-CMOS multiplexer (C<sup>2</sup>MOS MUX) tree, and a full-rate synchronous current-mode logic (CML) clock driver. A prototype realized in 40-nm CMOS accomplishes a wide 0.1-to-11 Gb/s...conference paper 2021
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Kumaran, A.K. (author), Pashaeifar, M. (author), D'Avino, Marco (author), de Vreede, L.C.N. (author), Alavi, S.M. (author)Continuous Class F (CCF) power amplifiers (PAs) overcome Class-F PA's disadvantage of narrow bandwidth by relaxing the short-circuit requirement at the 2<sup>nd</sup> harmonic while still maintaining 90.7% peak efficiency over the band of interest. This paper proposes four different CCF output networks, with their design procedure, suitable...conference paper 2021
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Hashemi, M. (author), Zhou, Lei (author), Shen, Y. (author), de Vreede, L.C.N. (author)This article presents the first application of a digital-intensive intrinsically linear digitally controlled class-E technique in a Doherty configuration. By careful nonlinear segmentation and multiphase RF-clocking along with overdrive-voltage control and automatic duty-cycle correction, it is shown that even the nonlinearities related to...journal article 2019
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Vlachogiannakis, G. (author), Pertijs, M.A.P. (author), Spirito, M. (author), de Vreede, L.C.N. (author)A compact sensing pixel for the determination of the localized complex permittivity at microwave frequencies is proposed. Implemented in the 40-nm CMOS, the architecture comprises a square patch, interfaced to the material-under-test sample, that provides permittivity-dependent admittance. The patch admittance is read out by embedding the patch...journal article 2018
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Hu, Z. (author), Vlachogiannakis, G. (author), Pertijs, M.A.P. (author), de Vreede, L.C.N. (author), Spirito, M. (author)A 0.14-μ m CMOS 2-D permittivity imaging matrix prototype operating at microwave frequencies is presented. It comprises 25 permittivity-sensing pixels, each consisting of a sensing patch connected to a dedicated RF bridge. A trans-conduct-ance stage converts the imbalance voltage to a current signal, subsequently down-converted to an...conference paper 2018
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Qureshi, A.R. (author), Acar, Mustafa (author), Pires, Sergio C. (author), de Vreede, L.C.N. (author)Packaged integrated low-pass quasi-load insensitive (QLI) class-E matching is proposed for the realization of energy-efficient wideband Doherty and outphasing transmitters. In view of this, a dedicated QLI class-E harmonic matching technique, suitable for in-package integration has been developed, optimized, and evaluated. As proof of concept...journal article 2018
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Alavi, S.M. (author), Staszewski, R.B. (author), De Vreede, L.C.N. (author), Long, J.R. (author)This paper presents a wideband 2 13-bit in-phase/quadrature-phase (I/Q) RF digital-to-analog converter-based all-digital modulator realized in 65-nm CMOS. The isolation between I and Q paths is guaranteed employing 25% duty-cycle differential quadrature clocks. With a 1.3-V supply and an on-chip power combiner, the digital I/Q transmitter...journal article 2014
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Hajian, M. (author), Kuijpers, B. (author), Buisman, K. (author), Akhnoukh, A. (author), Pelk, M. (author), De Vreede, L.C.N. (author), Zijdeveld, J. (author), Ligthart, L.P. (author), Spitas, C. (author)The design concept of passive and active reconfigurable reflectarray antennas has been proposed and tested. The antenna elements in the array are identical hollowed patches. In the first phase of study the slots are loaded with a SMD capacitor to set the required phase shift needed for array implementation. Simulations show promising results....journal article 2012
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- Staszewski, R.B. (author), De Vreede, L.C.N. (author) patent 2011
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Marchetti, M. (author), Pelk, M.J. (author), De Vreede, L.C.N. (author)Measurement arrangement and method for active load pull measurements of a device under test (1). A wideband analog-to-digital conversion block (3) is provided for obtaining measurement data. First and second injection signal generators (7, 8) are connected to a source side and a load side of the device under test (1). This set up allows to...patent 2009
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Nanver, L.K. (author), Schellevis, H. (author), Scholtes, T.L.M. (author), La Spina, L. (author), Lorito, G. (author), Sarubbi, F. (author), Gonda, V. (author), Popadic, M. (author), Buisman, K. (author), De Vreede, L.C.N. (author)This paper reviews special RF/microwave silicon device implementations in a process that allows two-sided contacting of the devices: the back-wafer contacted silicon-on-glass (SOG) substrate-transfer technology (STT) developed at DIMES. In this technology, metal transmission lines can be placed on the low-loss glass substrate, while the...journal article 2009
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Qureshi, J.H. (author), Pelk, M.J. (author), Marchetti, M. (author), Neo, W.C.E. (author), Gajadharsing, J.R. (author), Van der Heijden, M.P. (author), De Vreede, L.C.N. (author)A 90-W peak-power 2.14-GHz improved GaN outphasing amplifier with 50.5% average efficiency for wideband code division multiple access (W-CDMA) signals is presented. Independent control of the branch amplifiers by two in-phase/quadrature modulators enables optimum outphasing and input power leveling, yielding significant improvements in gain,...journal article 2009
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Marchetti, M. (author), Pelk, M.J. (author), Buisman, K. (author), Neo, W.C.E. (author), Spirito, M. (author), De Vreede, L.C.N. (author)A new wideband open-loop active harmonic load–pull measurement approach is presented. The proposed method is based on wideband data-acquisition and wideband signal-injection of the incident and device generated power waves at the frequencies of interest. The system provides full, user defined, in-band control of the source and load reflection...journal article 2008
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- Huang, C. (author), Buisman, K. (author), Nanver, L.K. (author), Sarubbi, F. (author), Popadic, M. (author), Scholtes, T.L.M. (author), Schellevis, H. (author), Larson, L.E. (author), De Vreede, L.C.N. (author) journal article 2008