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Antsos, Dimitrios

Publications and source records attributed to Antsos, Dimitrios.

Mars Technology Program (MTP) Communications and Tracking Technologies for Mars Exploration

The MTP Communications and Tracking Technology Development Program aims to develop critical enabling technology components and products that will make the future high capacity communications links from Mars possible. It comprises ten technology development tasks. This paper briefly describes each task and gives a summary of the current state of the research and future recommendations.

X-band

Fundamental Limitations Of Passive Power Dividers

Report presents novel theoretical analysis of performance of passive, multiport power dividers like those used to distribute power to radiating elements of array antennas. Typically, unit cell of power-divider network is three- or four-port subnetwork with one port terminated, and subnetworks of network cascaded in multiple layers, so that insertion losses are of major concern.

Antsos, Dimitrios

Modified Wilkinson Power Dividers For K And Ka Bands

Modified configuration for Wilkinson power dividers devised for operating frequencies in K and Ka bands (18 to 27 and 27 to 40 GHz, respectively). Overcomes some difficulties associated with increasing frequency, making possible to design and accurately predict performances of unequal-split power dividers for frequencies above X-band.

Antsos, Dimitrios

Equations For Designing Superconducting Transmission Lines

Characteristics of microwave circuits predicted accurately. Equations for propagation of quasitransverse electric and magnetic (TEM) waves along thin films of high-critical-temperature superconductors constitute basis of mathematical model useful in design of coplanar-waveguide, microstrip, and stripline microwave circuits. Model incorporated into older commercial software for computer-aided design of microwave circuit.

Antsos, Dimitrios

Modeling of planar quasi-TEM superconducting transmission lines

An application of the phenomenological loss equivalence method (Lee and Itoh, 1989) in modeling the microwave behavior of planar quasi-TEM superconducting transmission lines is presented. For validation of the model, data are used from measurements of a YBCO superconducting thin-film coplanar-waveguide lowpass filter on a lanthanum aluminate substrate. Measured and modeled S-parameters of an existing superconducting coplanar waveguide lowpass filter agree to within 0.3 dB in magnitude and 0.5 radians in phase. Extracted values for penetration depth and real part of the conductivity of the superconducting film are within 10 percent of other researchers' findings.

Antsos, Dimitrios