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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)
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)
Self-switching diodes (SSDs) were fabricated on as-grown and hydrogen-intercalated epitaxial gra-phene on SiC. The SSDs were characterized as zero-bias detectors with on-wafer measurements from 1 to 67 GHz. The lowest noise-equivalent power (NEP) was observed in SSDs on the hydrogen-intercalated sample, where a flat NEP of 2.2 nW/Hz 1 =2 and responsivity of(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)
An InP MMIC process was developed and optimized for ultra-low noise amplifiers (LNAs) operating at cryogenic temperature. The amplifiers from the process are working up to 100 GHz. The processed wafers are 4" and can carry more than 4000 3-stage units. For a significant number of 6-20 GHz 3-stage LNAs we have measured an average noise temperature of 5.8 K(More)
The suitability of InAs/AlSb HEMTs for cryogenic ultra low-power applications is investigated. Compared to room temperature, the device exhibited significantly improved drain current saturation, higher peak transconductance and lower gate current leakage at around 10 K. When tested in a three-stage hybrid 4-8 GHz LNA under cryogenic conditions, the LNA(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)
Fabrication and characterization of 225 nm gate-length InAs/AlSb HEMTs with excellent RF performance are reported. We show the importance of an insulating layer between the gate and the semiconductor to improve g<sub>m</sub>, f<sub>T</sub> and f<sub>max</sub>, and most important from a noise perspective, the gate-leakage current I<sub>G</sub>. By using an(More)