International Journal

Resonant substrate integrated near-field sensors are used for characterization of aqueous solutions at three different frequencies. In addition, Chinese hamster ovary (CHO) cells in a culture medium are characterized with the same sensors. Different concentrations as well as different vital states of cell suspensions are examined. The complex permittivity of the samples is evaluated using a linear

This paper reports on the design of a new power cell dedicated to Ku-band power amplifier (PA) applications. This cell called ?integrated cascode? has been designed in order to propose a strong decrease in terms of circuit size for PA. The technology used relies on 0.25-?m GaAs pseudomorphic high electron mobility transistors (PHEMT) of United Monolithic Semiconductors (UMS) foundry. A distributed

This paper presents a novel technology for the implementation of substrate-integrated waveguide (SIW) structures, based on a paper substrate and realized by an inkjet-printing fabrication process. The use of paper permits to implement low-cost microwave structures and components, by adopting a completely eco-friendly implementation technology. SIW structures appear particularly suitable for implem

Cognitive radio (CR) has generated a lot of interest because of the promise of wide instantaneous bandwidths which will improve data rates. Current social trends suggest that CR nodes will ultimately be mobile and handheld. This produces a need for small wideband antennas. The Chu limit imposes a restriction on what is obtainable with passive matching. In this paper, it is shown how a negative imp

This paper presents a hybrid antenna design for an optically powered super high frequency (SHF) radio frequency identification transponder applicable for the integration into metal. The key feature of the antenna is its ability to receive microwave signals at SHF for data communication and optical signals for the power supply of the transponder. The antenna design is based on a circular waveguide

In this paper, we present a non-resonant high impedance reflectometer with a reference impedance close to one of the tip probe of a near-field microwave microscope. We show that for an apex of the tip probe of 100 µm there is an optimum reference impedance close to 1 k?. To validate this approach a microwave circuit that makes use of lumped elements has been fabricated. A proof of concept is also

A compact, microstrip, two-stage, room temperature, single-ended low noise amplifier (LNA) is designed using commercial components for Aperture Tile in Focus (APERTIF), a square kilometre array (SKA) pathfinder project. Various techniques are investigated to insert inductance between the source pad of the package and the ground plane of the printed circuit board (PCB), with the chosen design able