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In Ilmenau, Germany, a new laboratory is under construction for testing mobile communication equipment, both satellite and terrestrial. This contribution focuses on Over-The-Air testing of terrestrial mobile terminals and on applications of Wave Field Synthesis in this laboratory. The terrestrial research in the lab will mainly serve scientific purposes, as research into OTA test methodologies, also...
A closed room environment is viewed as a lossy cavity, characterized by possibly a line of sight (LOS) component and diffuse scattering parts from walls and internal obstacles. A theory used in acoustics and reverberation chambers is applied for the electromagnetics case, and main issues related to measurement systems and antennas characteristics are discussed. The goal of this paper is the assessment...
Cognitive radio has been put forward to make efficient use of scarce radio frequency spectrum. Spectrum sensing is the cornerstone of cognitive radio. As a part of the effort toward building a cognitive radio network testbed, we have demonstrated real-time spectrum sensing. However, current hardware platforms for cognitive radio introduce time delays that actually undermine the accuracy of spectrum...
Industrial applications of wireless sensor networks often involve radio-harsh environments. These industrial settings typically include an abundance of metallic structures which obstruct, reflect, refract and scatter signals. As a result, RF channel modeling for these environments becomes necessary and important. In this paper, a WSN testbed emulating realistic industrial environments was constructed...
This work presents theoretical and experimental analysis of radio signals propagation in LOS and NLOS indoor propagation conditions. Specifically, propagation conditions in straight corridor and adjacent rooms are analysed. A statistical multi-parametric approach that was previously used in urban propagation conditions is adapted to the modelling of indoor communication channels. The model of the...
This paper describes configurable, 3.6 to 7.5 GHz pulse UWB transmitter IC targeted for neurological implants with high data rate requirements. Each cycle of the RF pulse is digitally programmable in amplitude and duration, enabling a very flexible shaping of the transmitted PSD signal, without the use of an output filter. The transmitter achieves a maximum of 34% of energy efficiency when drawing...
A true time-delay-based bandpass multi-beam matrix at mm-Waves is introduced that is suitable for applications with instantaneously wide bandwidth signals and for MIMO systems. A 0.13 ??m SiGe BiCMOS chip prototype covers the 30-to-40 GHz frequency range instantaneously and supports 6 channels while producing 7 simultaneous beams with 18?? spatial resolution and ??54?? of spatial coverage.
In this paper, directional MIMO measurements in an indoor office environment are presented. A 5-D ESPRIT estimation algorithm is used to extract parameters associated with discrete propagation paths, such as their azimuth of arrival, azimuth of departure, delay, and power. The estimated path parameters are grouped into clusters using the statistical K-power-means algorithm. Statistical distributions...
This paper presents a wide band 60 GHz MIMO channel measurement system using a VNA and 3-D arrays at both ends. It uses virtual antenna arrays which can be reconfigured easily. The bandwidth of the system is 3.5 GHz, which leads to a time resolution of 0.29 ns. This fine resolution is suitable for characterizing dense multipaths in indoor environments. Line of sight (LOS) and obstructed line of sight...
Code division multiplexing (CDM) based MIMO channel sounder architecture is excellent at measuring fast fading channel. In this paper, loosely synchronous (LS), Kasami and chaotic sequences are suggested as candidates for the code that will be used in CDM architecture. Among those sequences, then, the best suitable sequence for channel sounding is examined through simulation. And by proposing the...
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