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GaN HFET MMICs with integrated Schottky-diode for highly efficient digital switch-mode power amplifiers at 2 GHz
This work describes the integration of Schottky diodes into fast GaN MMIC process technology suitable for the realization of switch-mode power amplifier core chips for class-S operation at 2 GHz. With the demonstration of this technology, the so-called third-quadrant issue, which reduces the efficiency in band pass-?-? class-S operation can be diminished on device level. Compared to a hybrid diode
In-situ probes for patch antenna array calibration
A novel calibration network for patch antennas is proposed. We introduce magnetically coupled in-situ probes, which excite the fundamental patch mode. In that way, finite array effects and mutual coupling are taken into account, providing the opportunity for accurate online calibration of active antenna terminals. The specific advantages of the approach are demonstrated for linearly polarized patc
Efficiency and linearity analysis of a burst mode RF PA with direct filter connection
Burst mode operation is proposed as an efficiency improving technique for power amplifiers. The core idea is to modulate the amplitude of the envelope signal into a series of square-wave pulses such that the width of the signal burst or the total amount of pulses are varied according to the envelope. The phase information is still contained by the timing of the pulses. This work presents the effic
Reconfigurable digital receiver design and application for instantaneous polarimetric measurement
This paper presents the development of a reconfigurable receiver to undertake challenging signal processing tasks for a novel polarimetric radar system. The field-programmable gate arrays (FPGAs)-based digital receiver samples incoming signals at intermediate frequency (IF) and processes signals digitally instead of using conventional analog approaches. It offers more robust system stability and a
A 60 GHz 14 dBm power amplifier with a transformer-based power combiner in 65 nm CMOS
A 52?61 GHz power amplifier (PA) is implemented in 65 nm bulk complementary metal oxide semiconductor (CMOS) technology. The proposed PA employs a transformer-based power combiner to sum the output power from two unit PAs. Each unit PA uses transformer-coupled two-stage differential cascode topology. The differential cascode PA is able to increase the output power and ensure stability. The transfo
Broadband permeability measurement method for ferrites at any magnetization state: direct problem
A broadband permeability measurement method based on the full-wave electromagnetic (EM) analysis of a non-reciprocal transmission line is presented. The dispersion diagram for the first significant modes inside the ferrite loaded section of the line is obtained. The presence of magnetostatic modes generated by the magnetized ferrite inside the line is verified. Using a mode matching technique, the
60 GHz WLAN applications and implementation aspects
Various wireless applications are currently under development for the unlicensed 60 GHz band. This paper describes three examples with different system requirements. The first two are point-to-multipoint wireless networks (in an airplane and in a car) and the third one is a short range point-to-point connection. Special requirements of the applications are a high number of users for the point-to-m
An overview of 60 GHz location systems operating in multipath environments
This study deals with a non-exhaustive overview of location systems operating in the 60 GHz frequency band. Both impulse and frequency hopping topologies are considered and the performances of the two realized systems are presented. For each system, a specific signal processing has been implemented to prevent the degradation of the location error from the impact of the multipath propagation.
A homodyne transceiver MMIC using SiGe:C technology for 60 GHz wireless applications
A highly integrated transceiver microwave monolithic integrated circuit (MMIC) manufactured in a 200-GHz SiGe:C production technology is presented, applicable for sensing- and broadband communication applications. To simplify the analog frontend, the fully differential design is based on a homodyne architecture. It comprises an LO signal generation unit based on a wideband 60 GHz fundamental Volta
Electrical performances of AlInN/GaN HEMTs. A comparison with AlGaN/GaN HEMTs with similar technological process
A study of the electrical performances of AlInN/GaN High Electron Mobility Transistors (HEMTs) on SiC substrates is presented in this paper. Four different wafers with different technological and epitaxial processes were characterized. Thanks to intensive characterizations as pulsed-IV, [S]-parameters, and load-pull measurements from S to Ku bands, it is demonstrated here that AlInN/GaN HEMTs show