Andrei A. Muller

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This letter proposes a spherical 3-D Smith Chart suitable for representing both active and passive microwave circuits. Using the mathematical concept of the Riemann sphere, the extended reflection coefficient plane is transformed into the surface of the unit sphere. Since the proposed Smith Chart compiles the whole complex plane, all possible loads are(More)
The paper introduces the concept of reflection matrices in the coupling matrix filter reconfiguration. It is shown that reflection matrices are complementary to rotation matrices a useful concept that can be used alternatively to rotation matrices in the similarity transformations that are applied in order to transform the coupling matrix to a suitable(More)
The design of a slot coupled microstrip patch antenna with four parasitic elements for the 77 GHz frequency range is presented. Full wave electromagnetic simulations were used for antenna modeling and optimization. The antenna was fabricated using Ferro A6-M Low Temperature Co-fired Ceramic technology. The “on wafer” measurements showed a(More)
The aim of this paper is to describe the results obtained on the radiation pattern scanning of a ferrite supported resonating CPW antenna based on metamaterial transmission lines approach. The scanning effect is obtained as an effect of remarkable properties of the ferrite substrate in the microwave frequencies domain when applying a biasing magnetic field.(More)
This paper analyzes and compares voltage and power wave reflection coefficients using a visual representation which fully exploits that both coefficients are directly related to the geometry of direct inversive transformations in the extended impedance plane. In order to compare the two concepts for complex impedance ports, the 3D Smith chart tool is used(More)
This paper presents the results in frequncy tuning of a ferrite supported resonating CPW antenna based on CRLH (Composite Right/Left-Handed) transmission lines. The tuning is obtained by magnetically polarizing the ferrite substrate with a magnetic biasing field variable between 0 T and 0.26 T. Data obtained by simulation with a suitable microwave software(More)
ELECT Unilateral transducer constant power gain circles play an essential role in the design of radio-frequency amplifiers and active modulators, as they help to determine optimal impedance matching conditions to meet gain and stability specifications. It is shown that these gain circles are a subfamily of Apollonius circles. For better visualisation,(More)
The paper presents the results concerning the radiation characteristic scanning of a ferrite supported resonating CPW antenna based on CRLH (Composite Right / Left-Handed) transmission lines. The scanning effect is obtained by magnetically polarizing the ferrite substrate. Data obtained by simulation with a suitable microwave software indicate an azimuthal(More)
The paper deals with the radiation characteristic scanning of a ferrite supported resonating CPW antenna based on CRLH (Composite Right/Left-Handed) transmission lines. The scanning effect is obtained by magnetically polarizing the ferrite substrate with a magnetic biasing field which varies between 0 T and 0.16 T. Data obtained by simulation with a(More)
The paper presents in premiere a simple mapping property of the sum of the reflection and transmission parameters of reciprocal two port networks. It is proved that although the reflection and transmission parameter may have very complicated paths on the Smith chart, their sum will be always moving on the unit circle if the circuit is symmetric and(More)