Mode-stirred chamber sample selection technique applied to antenna correlation coefficient

Mode-stirred chambers provide an excellent tool for antenna characterization. Recent research has focused on making the mode-stirred chamber technique more versatile. One result of these efforts is the sample selection technique, by which a subset of data with specific properties is extracted from a measured set of raw data. This paper presents how to apply the sample selection technique to measurements of the correlation coefficient in dual antenna measurements, for example, for diversity or MIMO applications. Theoretical background and useful mathematical relations are presented. The application is verified through measurements.This work was supported in part by the Spanish National R & D Programme through TEC 2008-05811 and by Fundacion´ Seneca, the R & D coordinating agency for the Region of ´ Murcia (Spain) under the 11783/PI/09 and 11610/IV2/09 Projects

Multipath propagation simulator for V2X Communication Tests on Cars

Test and evaluation of wireless communication performance with cars can be done in many ways. One approach, for both vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) tests, is to use a multipath propagation simulator to achieve realistic signal environments for the different communication systems under test. Multipath propagation simulators have previously been shown to be useful for testing mobile handsets. Specific issues related to tests with cars are the large size of the test object and the disturbances it can cause. In this paper we experimentally study how different design parameters of the multipath propagation simulator affect the received signals. The analysis of the setup as well as the data is performed using the so-called “Design of Experiments” method

Limit for the proportion of remaining samples in the modestirred chamber sample selection technique

An expression is derived for the maximum proportion of remaining samples in the sample selection technique for mode-stirred chamber measurements. The limit is independent of the selection algorithm used. The limit is verified in simulations as well as measurement examples.This work was supported in part by the Spanish National R&D Programme through TEC2008-05811, and by Fundacio´n Se´neca, the R&D coordinating agency for the Region of Murcia (Spain) under the 11783/PI/09 and 11610/IV2/09 project

Multipath simulator measurements of handset dual antenna performance with limited number of signal paths

Antenna pairs for diversity or MIMO functionality are characterized under the assumption of a certain statistical distribution of the incident signals over angle and polarization, but also assuming a signal environment with a large number of signal paths. In many real-life environments, however, only a few signal paths contain most of the transferred power. A multipath simulator can be used to realize signal environments with a controlled number of signal paths. This paper presents measurements of dual antenna performance using amultipath simulator with 2–16 signal paths. The results are analyzed in terms of statistical power distributions,power imbalance, correlation coefficient, multiplexing efficiency, and diversity gain. Differences in performance depending on the number of signal paths are noted, illustrating the value of considering the number of signal paths in characterization.The work was supported in part by MICINN (Project TEC2008-05811) through an FPI doctoral grant (BES-2009-013764

Sample selection algorithms for enhanced MIMO antenna measurements using mode-stirred reverberation chambers

Mode-stirred reverberation chambers (MSRCs) are a useful tool for measuring several wireless-related MIMO antenna parameters. In a conventional single-cavity MSRC, the emulated fading environment is isotropic and the amplitude of the signal is Rayleigh distributed. Previous contributions have enhanced the emulation capabilities ofMSRCs so as to include the ability to emulate Rician- and non-isotropic fading environments. In this contribution, arbitrary amplitude probability density functions (PDF) emulation using a MSRC is presented by selecting parts of the sample set that forms different statistical ensembles. Several algorithms are presented and compared in terms of computation time and power accuracy using simulated as well as measured data from different MSRCs to obtain Rician, on-body and amplitude PDFs of standardized models. The technique is patent-protected by EMITEThis work was supported in part by the Spanish National R&D Programme through TEC2008-0581

Design Rules for Multipath Simulator Antenna Array

Multipath simulators are a technique for characterizing wireless terminals, such as for instance mobile phones. A multipath simulator distributes the measurement signal over an array of antennas encircling the test object. When building a multipath simulator, the antenna array should be given an optimal design with respect to the characteristics of the test objects, the parameters to be measured, and the desired measurement accuracy. This report presents mathematical relations which can be used for optimizing the antenna array. The relations are mostly derived theoretically using simple assumptions, and in some instances found from numerical simulations. The report assumes an array with the antennas evenly distributed on a circle with the test object at the center, and a measurement signal power which is uniformly distributed over the array. Considered measured quantities include power, correlation coefficient, and the statistical distribution of amplitudes