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[EN] This paper presents an analysis of the massive MIMO channel in an indoor picocell. The analysis is based on the results of a measurement campaign carried out in the 3.2 to 4 GHz band in a scenario of reduced size and with a symmetrical geometry. It is well known that the performance of massive MIMO systems depends largely on the fact that the radio channel meets the condition of favorable propagation. In order to evaluate the performance of the resulting massive MIMO channel, results concerning the sum capacity are included. A second factor that determines the performance of massive MIMO systems when it is operated in a TDD-OFDM framework is the frequency selectivity of the channel that limits the size of the coherence block. In this sense, results of the coherence bandwidths achieved are also presented and analyzed.

[EN] In this conference contribution, we present millimeter-wave (mmWave) propagation measurements for an office environment from 25 to 40 GHz and investigate the path loss using the most common empirical models proposed in WINNER-II and adopted by the 3GPP: the single-frequency floating-intercept (FI) model, the single-frequency close-in (CI) free space reference distance model, the multi-frequency alphabeta-gamma (ABG) model and the close-in free space reference distance with frequency path loss exponent (CIF). Both line-ofsight (LOS) and obstructed-LOS (OLOS) propagation conditions have been considered. The mean value of the model parameters, and their 95 % confidence intervals, have been derived using regression and optimization techniques.

[EN] In this paper, path loss and time-dispersion results of the propagation channel in a typical office environment are reported. The results were derived from a channel measurement campaign carried out at 26 GHz in line-of-sight (LOS) and obstructed-LOS (OLOS) conditions. The parameters of both the floating-intercept (FI) and close-in (CI) free space reference distance path loss models were derived using the minimum-mean-squared-error (MMSE). The time-dispersion characteristics of the propagation channel were analyzed through the root-mean-squared (rms) delay-spread and the coherence bandwidth. The results reported here provide better knowledge of the propagation channel features and can be also used to design and evaluate the performance of the next fifth-generation (5G) networks in indoor office environments at the potential 26 GHz frequency band.

(c) 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works., [EN] Concerning the design and planning of new radio interfaces for the fifth-generation (5G) systems, this paper presents a useful contribution to the characterization of the wideband indoor radio channel in the 3-4-GHz frequency band. A measurement campaign has been carried out in two different indoor scenarios to analyze some of the most important wideband parameters of the propagation channel, including a thorough analysis of its behavior to meet the new radio technology challenges. The channel measurement setup consists of a virtual vertical uniform array at the receiver side of the link that remains at a fixed position, whereas the transmitter side, which is equipped with a single antenna, is placed at different positions in the environment under analysis. The measurement setup emulates the up-link of a multi-user multiple-input multiple-output (MIMO) system and allows obtaining the broadband parameters of the multiple channels that are established between the transmitter and each one of the antennas of the receiver array. The results and conclusions about the path loss, temporal dispersion, and coherence bandwidth are included, along with an analysis of the spatial correlation between wideband channels when one of the antennas is an array.

[EN] This study presents an analysis of the capabilities of using multi-user multiple input multiple output (MU-MIMO) in indoor environments at the 3-4 GHz band through an empirical characterisation of the MU-MIMO channel, obtaining a statistical description of the degree to which this specific multi-user channel verifies the condition of 'favourable propagation'. Different metrics have been considered to measure the degree of orthogonality between the channels, such as the orthogonality coefficient or the condition number. In addition, in order to obtain a direct measure of the goodness of the channel in terms of the achievable spectral efficiency, the capacity of the channel has been calculated for different numbers of users and base station antennas and compared with theoretical i.i.d. Rayleigh channels.

The Conchos Mexican basin is part of the Rio Grande/Rio Bravo Basin. This basin provides water to irrigate 120,000 ha and water supply to one million of population and its different activities in the state of Chihuahua. Moreover, this basin has historically delivered most of the water, around 54%, to the United States of the six Mexican rivers included on the international Water Treaty signed between these two countries in 1944. Drought occurrences, such as the 1950's and 1990's, have demonstrated the basin's vulnerability. This has produced not only considerable economic losses on the region but also generated economic problems and political frictions with United States given the inability of México to comply with the Water Treaty's specifications. Because of this problematic, the lack of understanding of the water resources management, and the poor development and application of some new introduced water resource policies such as water right transfers, the present study is focused to develop two research lines: 1) to create a Decision support System (DSS), a lumped semi-distributed model, created using System Dynamics (SD) and running in monthly basis. For the short and long term, the DSS carries out simulation of water resources allocation, reservoir operation policies, increased water distribution efficiencies and temporary water rights transfers. And 2) to make an analysis of the current water right allocation mechanism aimed to understand more this current policy from an institutional perspective. The final expected outcome of this research is to identify alternatives oriented not only to improve the water resources management on the Conchos basin but also to facilitate México’s compliance with the Treaty requirements.