D. Neculoiu

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The radio-frequency identification (RFID) concept is expanded to millimeter-wave frequencies and millimeter-wave identification (MMID) in this paper. The MMID concept and a comparison with UHF RFID are presented, showing the limitations and benefits of MMID. Three feasible applications are suggested for MMID, which are: (1) wireless mass memory; (2) an(More)
A GaAs micromachined uniplanar quasi-optical mixer is presented for the first time. The main block of the circuit is a membrane-supported double folded slot antenna monolithically integrated with a millimeter-wave Schottky diode. The circuit is designed for the 38 GHz frequency range, using coplanar waveguide technology and full-wave electromagnetic(More)
This paper presents the design, fabrication and “on wafer” characterization of membrane-supported YagiUda CPW fed antenna structures. The antennas were designed for the 60 GHz and 77 GHz frequency operating ranges. The 60 GHz antennas were fabricated on a semi-insulating GaAs membrane using GaAs micromachining. The 77 GHz antennas were manufactured on 1.4(More)
GaN is a wide-bandgap semiconductor with still unexplored capabilities for ultraviolet detection. To exploit GaN properties better for ultraviolet detection, a metal-semiconductor-metal-type photodetector structure was designed and manufactured on a 2.2 microm thin GaN membrane fabricated by micromachining techniques. As a result, a very low dark current(More)
In this paper, a novel differential microstrip patch antenna (DMPA) is designed and used to feed a lens antenna for short range F-band MIMO radars. The DMPA is fed differentially by a pair of coupled lines. The antenna is connected via a differential impedance matching network to the differential output of the modules, eliminating this way the need of a(More)
This paper presents a field-effect transistor with a channel consisting of a two-dimensional electron gas located at the interface between an ultrathin metallic film of Ni and a p-type Si(111) substrate. The gate length is L = 2 μm, its width is W = 180 μm, and the source-drain separation is 188 μm, the role of the gate dielectric being played by the(More)
This paper describes the design, manufacturing and experiments of a lumped element band pass filter in a new topology. The design starts from a second order capacitive coupled resonator topology. An additional series inductor is inserted in the filter classical topology, for shifting two transmission zeros on the real frequency axes in the filter’s band(More)
This paper presents the manufacturing and the characterization of GaN membrane supported MSM photodetector structures obtained by means of nanolithographic techniques. Two different runs of MSM photodetectors, with different dimensions of the MSM structures and different GaN membrane thickness, have been performed and the detectors performances are(More)
This paper presents the measurements and modelling of the electromagnetic propagation in graphene in the mm-wave frequency range. Two test structures were fabricated on high resistivity silicon substrate and tested. The first is a reference structure and it was used to extract the electromagnetic parameters of the substrate up to 60 GHz. The second(More)