Jan V. Grahn

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In this paper, a detailed linearization procedure for dynamic load modulation (DLM) transmitter architectures is proposed for the first time. Compared with the conventional single-input/single-output digital predistortion (DPD) approach used with traditional power amplifiers (PAs), the proposed linearization scheme is based on a regular memory DPD in(More)
A monolithic microwave integrated circuit (MMIC) process based on an in-house SiC MESFET technology has been developed. The process uses microstrip technology, and a complete set of passive components, including MIM capacitors, spiral inductors, thin-film resistors, and via-holes, has been developed. The potential of the process is demonstrated by an 8-W(More)
A semiclassical 2D ensemble Monte Carlo simulator is used to perform a physical microscopic analysis of kink effect in InAs/AlSb High Electron Mobility Transistors (HEMTs). Due to the small bandgap of InAs, these devices are very susceptible to suffer impact ionization processes, with the subsequent hole transport through the structure, both implicated in(More)
Electrical characterization and modeling of 2 times 50 mum gatewidth InAs/AlSb HEMTs with 225 nm gate-length have been performed. The fabricated devices exhibited a transconductance g<sub>m</sub> of 650 mS/mm, an extrinsic cutoff frequency f<sub>T</sub> and an extrinsic maximum frequency of oscillation f<sub>max</sub> of 120 and 90 GHz, respectively,(More)
0.5-13- and 24-40-GHz broadband cryogenic monolithic-microwave integrated-circuit low-noise amplifiers (LNAs) have been designed and fabricated using a 130-nm InP HEMT process. Packaged LNAs have been measured at both 300 and 15 K. At 300 K, the measured minimum noise temperature of the 0.5-13-GHz LNA was 48 K at 7 GHz with a gain between 34-40 dB. At 15 K,(More)
Passive components for use in planar Monolithic Microwave Integrated Circuits (MMICs) based on High Electron Mobility Transistors (HEMTs) on indium phosphide substrates are presented. Design, fabrication, and modeling issues of capacitors, resistors, inductors, transmission lines, via holes, and air bridges have been addressed. Sputtered thin films have(More)
The DC properties of 110-nm gate-length InAs/AlSb-based HEMTs at cryogenic (30K) and room temperature (300K) have been investigated. Compared to 300K, devices at 30 K exhibited lower on-resistance (RON) and output conductance (gDS), a higher transconductance (gm) and a more distinct knee in the IDS(VDS) characteristics. The improvement in the DC performance(More)
In this paper a highly linear amplifier using an in-house gallium nitride (GaN) high electron mobility transistor (HEMT) technology is presented. A 3 dB bandwidth of 2.7&#x2013;3.6 GHz with a maximum gain of 18 dB was measured. The output third-order intercept point (OIP3) was measured to 39 dBm with a maximum power consumption of 2.1 W. With a reduction of(More)
In this work, by means of Monte Carlo simulations, the static and dynamic behavior of isolated-gate InAs/AlSb high electron mobility transistors (Sb-HEMTs) has been studied and compared with experimental results. The influence of the existence of a native oxide under the gate, the value of the surface charges in the gate recess and the possible variation of(More)