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Presented is a method to produce a 2D reference test zone for over-the-air measurements in a random line-of-sight environment for vehicular applications. The ideal threshold receiver model is used to design the chamber array at 3 GHz for LTE/LTE-A systems. The analysis focuses on the fluctuations of the reference power measurements at a user-defined probability of detection level of bit-streams. Numerical...
The present paper describes the paradigm shift in OTA testing that came with the arrival of the 4G wireless system. The testing was previously mainly done in anechoic Line-Of-Sight (LOS) environments, and now in 4G it is done in reverberation chambers, emulating Rich Isotropic MultiPath (RIMP). Now we are preparing for the 5G wireless system, which is expected to have mm-wave antennas with steerable...
We derive the probability of detection functions of 1- and 2-bitstreams for polarization multiple-input multiple-output antenna systems in random line-of-sight propagation conditions. The derivations are produced assuming that the angle-of-arrival of the field impinging at the receive antenna is fixed. Hence, randomness is only due to the direction of polarization of the incident field relative to...
We derive the Multiple-Input Multiple-Output (MIMO) efficiency of the Zero-Forcing (ZF) receiver algorithm in Random Line-Of-Sight (Random-LOS). We make use of the Probability-of-Detection (PoD) curves based on the ideal digital threshold receiver model in the derivations. We show that the MIMO efficiency in this case, is mainly determined by two factors: the smallest channel gain of the two available...
LTE throughput measurements in a Random Line-of-Sight (Random-LOS) setup have been performed. The effect of polarization-randomness on the level of detection threshold of one or two bitstreams has been investigated. Good agreement is shown between theory and experiments for the SISO, SIMO and MIMO cases.
We evaluate the performance of a dual-polarized wideband antenna in terms of polarization-MIMO in Random-LOS for two different modes of operation: 2 and 4-port excited mode. The 2-port mode was obtained by differential excitation of two opposite ports of the 4-port design by using two baluns. The Zero-Forcing receiver throughput is evaluated based on the Probability of Detection of two bitstreams...
We present initial Over-The-Air (OTA) throughput measurements of an LTE device in a Volvo XC90 car with roof-mounted antennas. The measurements were performed in a semi-anechoic chamber and only in the horizontal plane. The throughput results are presented as a probability of detection (PoD) in 2D Random Line-Of-Sight (Random-LOS) with fixed polarization of the antenna at the base station side. Two...
Autonomous cars will in a near future drive around in cities and on highways. Antennas will then be needed to secure the wireless connection to these cars. To be able to test the antennas we have defined two edge environments: the Random Line-of-Sight (LOS) and the Rich Isotropic Multipath (RIMP). This paper shows a throughput performance comparison between measurements and simulations of a car-roof...
Rich Isotropic Multipath (RIMP) environment like reverberation chamber (RC) has proven to be useful for characterizing mobile LTE devices. The user statistics have larger effect in environments with stronger Line-Of-Sight (LOS), because the angle of arrival (AoA) and the polarization of the LOS contribution become randomized due to the user. Thus, we introduce the term Random-LOS. The present paper...
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