International Journal

The paper presents the first attempt to develop parameters that are invariant to polarization, aimed at classification and recognition of complex radar objects. Both the simplest (two-point) model and multipoint models of a complex object are analyzed using the so-called emergence principle and a generalization of the interference laws. The polarization invariant parameters of scattered fields and

A new structure is proposed in this article, to operate as wideband and wide-angle flat Radome. In this structure several dielectric and ferrite layers are placed successively, one next to the other, to behave as a matched layer. First, the relationship between the permittivity and permeability of a required fictitious mixed material is obtained. Then the required permittivity and permeability of

A new structure is proposed in this article, to operate as wideband and wide-angle flat Radome. In this structure several dielectric and ferrite layers are placed successively, one next to the other, to behave as a matched layer. First, the relationship between the permittivity and permeability of a required fictitious mixed material is obtained. Then the required permittivity and permeability of

We report on the development of W-band (75?110 GHz) heterodyne receiver technology for large-format astronomical arrays. The receiver system is designed to be both mass producible, so that the designs could be scaled to thousands of receiver elements, and modular. Most of the receiver functionality is integrated into compact monolithic microwave integrated circuit (MMIC) amplifier-based multichip

Millimeter-wave wireless space-division-multiplexing signals were discriminated by a newly developed electro-optic modulator using an array of antenna-coupled electrodes and polarization-reversed structures of ferroelectric optical crystals. Discrimination with channel isolation over 13 dB was obtained for two 38 GHz wireless signals with an irradiation angle difference of 15° by use of a fabricat

In this paper, we present a continuously tunable phase shifter realized in MEMS technology. Varactors with liquid crystal as a tunable dielectric layer underneath gold bridges are used to build a loaded line phase shifter. Measurements show that the phase shifter has a differential phase shift of 92°, a figure of merit (FoM) of 42°/dB and an input matching of ?19 dB at 76 GHz.The tuning speed of t

A new setup is proposed for the measurement of current?voltage pulsed characteristics of electron devices. The main advantages of the system consist in: shorter pulse widths through generation in a 50-? environment, simple average current monitoring through separation of the direct and alternate current paths, setting of average voltage values independently of pulse amplitudes and duty cycle, and

This paper presents a frequency-modulated continuous-wave (FMCW) radar operating at 120 GHz, which features silicon?germanium (SiGe) chips that employ HBTs with 320 GHz f. The chipset comprises a fundamental-wave signal-generation chip with a voltage-controlled oscillator (VCO) that provides frequencies between 114 and 130 GHz and a corresponding dual?transceiver (TRX) chip that supports monostati

Delay time measurements are a commonly used technique for the characterization of dielectric materials. Especially with regard to the characterization of water?solid mixtures like soil or grain delay time measurements, e.g., time domain reflectometry offers a powerful method. However, the accuracy of reflection measurements is limited due to multiple reflections caused by inhomogenities of the env