An eigen-analysis of compact antenna arrays and its application to port decoupling. - In: IEEE transactions on antennas and propagation, ISSN 1558-2221, Bd. 56 (2008), 2, S. 360-370
http://dx.doi.org/10.1109/TAP.2007.915450
AlGaN/GaN-based MEMS with two-dimensional electron gas for novel sensor applications. - In: Physica status solidi, ISSN 1610-1642, Bd. 5 (2008), 6, S. 1914-1916
http://dx.doi.org/10.1002/pssc.200778424
Nanomechanics of single crystalline tungsten nanowires. - In: Journal of nanomaterials, ISSN 1687-4129, Bd. 2008 (2008), 638947, S. 1-9
https://doi.org/10.1155/2008/638947
Qualification of a compact Ka-band switch matrix for on-orbit-verification. - In: GeMiC 2008, (2008), S. 454-457
A design formulation of a periodic high-impedance surface for a miniaturised antenna array. - In: Metamaterials 2007, (2007), S. 503-506
The focus of our work is the miniaturisation of a dipole antenna array by two complementary means. On the one hand, we want to place the antennas close above a high-impedance surface. On the other hand, we want to reduce the coupling between the antennas so that the elements can be placed at separations less than [lambda]/2. We derive a formulation to design analytically a high-impedance surface consisting of a periodic structure, which displays a surface wave band gap for a range of wavelengths much larger than the periodicity of the structure. For frequencies below the band gap, the structure supports backward waves, above the band gap forward waves are supported. Our considerations are verified by measurements.
Comparison of high resolution patterning technologies for LTCC microwave circuits. - In: Proceedings and exhibitor presentations, (2007), insges. 6 S.
Sensing applications of micro- and nanoelectromechanical resonators. - In: Proceedings of the Institution of Mechanical Engineers, ISSN 2041-3092, Bd. 221 (2007), 2, S. 59-65
http://dx.doi.org/10.1243/17403499JNN100
High performance 3-dimensional hybrid-integrated switch matrix for Ka-band satellite communication applications based on ceramic multilayer technology. - In: Proceedings, (2007), S. 1-8
LTCC multilayer technology enables very compact 20 GHz switch unit for space applications. - In: Proceedings, (2007), S. 500-504
A 4x4 switch matrix had to be realized within the project KERAMIS (Ceramic Microwave Circuits for Satellite Communications) of the German space agency DLR: This project aims at the development of innovative and inexpensive components for future applications in multimedia satellite communications. The rationale of the project is to exploit the possibility of integrating passive and active components in LTCC multilayer structures. This opens possibilities to minimize the complexity of the semiconducting components. - The working frequency of the device was in the 20 GHz band. A six layer construction with 7 conducting levels was chosen. The semiconductor switch dies were countersinked in cavities on both the top and the bottom of the circuit. The active chips were mounted using electrically conductive epoxy and wire-bonded afterwards. For testing purposes additional cavities were situated on the top side. The matrix was hermetically sealed by covers on both sides. These covers were also made in LTCC technology. Due to the complexity of the circuit 50æm lines and spaces had to be applied using fine line screen printing. The minimum distance between the edges of the cavities and the wiring was 75 æm. For cavities and vias mechanical punching and laser cutting were used. - The paper describes the technological processes and their particularities applied to manufacture this ambitious circuit.
Tunable dielectric material embedded in LTCC for GHz-frequency-range applications. - In: Proceedings, (2007), S. 290-293