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Time-varying K factor of the mm-Wave vehicular channel: Velocity, vibrations and the road quality influence

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... Therefore, they fail to warrant longer connectivity time. To warrant better useful policies within a short training time, studies in [15,17,18,20,21,22] incorporate RL with JMLS and GT techniques. In [21] the particle-filter-based RL is incorporated to predict a finite number of disturbances and states within a randomly chosen sample of trajectories. ...
... In [21] the particle-filter-based RL is incorporated to predict a finite number of disturbances and states within a randomly chosen sample of trajectories. The author in [22] amalgamates JMLS formulation into game theory concepts to tackle distributed decision-making scenarios. All these concepts aim to improve GT and DRL performance. ...
... To replicate each cluster, different powers and durations are used, which is reliant on a number of rays spread around a common cluster angle of arrival and departure (see (1) - (4)]. Parameters here rely on the time varying Rician K factor determined by the instantaneous velocity of the measured vehicle [2][5] [22]. A summary of simulation parameters is given in Table I while more details can be found in [8]. ...
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The fifth generation (5G) mobile communication adopted the usage of Millimeter Wave (mmWave) bands to ignite prospects of gigabit data rates in mobile networks. However, mmWave propagation is highly susceptible to competing factors of user and topographic dynamics: they formulate irregular cell patterns. The irregularities in mmWave cell patterns cause unreliable connectivity and can instigate unnecessary Handoffs (HOs). This behavior ultimately increases the risk of 5G link failures. To improve mmWave link connectivity hence guarantee continuous connectivity in 5G mobile communication, this paper proposes a HO scheme that predicts target link deterioration patterns to select the most reliable mmWave link for a mobile user. The scheme is based on Game Theory (GT) and Jump Markov Linear Systems (JMLS). JMLSs are known to account for abrupt/erratic changes in system dynamic predictions. We amalgamate GT with JMLS capability to predict target mmWave link pattern/behavior after the HO execution. Specifically, given channel gain and received power variation over distance, the GT-JMLS HO scheme predicts the sustainability of the signal-interference-noise ratio (SINR) pattern of a target link above threshold. This is paramount to reducing the selection of mmWave links that prematurely fail or require multiple HOs to sustain connectivity over a short distance or period. Our simulation results show that our proposed HO scheme offers target links with higher: throughput, energy efficiency, reliability, and longer dwell time between HOs than classical HO schemes.
... We would like to point out that this study aims at the hardware description of the sounder and its data processing techniques. Thus, we do not tend to present results of the real-world channel sounding campaigns, as we have done this, e.g. in [8], [9] or [10]. All results presented in this study are only back-to-back tests. ...
... [8], with m-sequences as an input signal, to measure and characterise the time-varying intra-vehicle channel of a moving car. The system was also used in [9,10] to evaluate the effects of vehicle vibrations on the millimetre wave channel via the delay-Doppler spreading functions. ...
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This study describes a time domain channel sounder based on binary sequences. The channel sounder system consists of several off-the-shelf laboratory instruments and is controlled by a PC. The frequency band of interest is the unlicensed millimetre wave band, 57-64 GHz. A crucial feature of the proposed system is its fast measurement speed enabling measurements of realistic vehicular scenarios. The main part of the study is dedicated to the description and analysis of the system behaviour when nonlinear components, such as mixers, low noise amplifiers or power amplifiers are used. The contributions of this study are the description of how to mitigate these effects utilising several different excitation signals and the evaluation and comparison of the channel sounder performance in terms of the spurious-free dynamic range parameter.
... In [83], 73 GHz V2V large-scale fading and small-scale fading analysis were provided for approaching vehicles. The appearance of intra-vehicular Doppler spectra of vibrations while the vehicle operating have been shown in [84,85]. The study of [86] investigated signal-to-noise ratio (SNR) fluctuations for 60 GHz transmissions with 5 MHz bandwidth in a vehicle-to-infrastructure scenario. ...
Thesis
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Mobile communications has become so successful today that conventional radio technologies, in traditional frequency bands below 6 GHz, are soon reaching their limits. To be able to develop massively deployed, ubiquitous, data-hungry, mobile applications, this study explores the use of higher frequency bands, or so-called millimeter waves in mobile communications. These radio bands above 30 GHz are mostly unoccupied and have dozens of gigahertz of bandwidth available. Moreover, advances in electronics have now made it possible to utilize these bands cost effectively. This thesis studied the millimeter wave wireless channel through conducting the following experiments: (1) two indoor millimeter wave measurement campaigns with directive horn antennas on both link ends, (2) an outdoor vehicular millimeter wave measurement campaign employing a horn antenna and an omni directional antenna, and (3) a railway communications ray-tracing study with directive antennas on both sides. In all the cases, the data obtained show that the millimeter wave wireless channel has very limited multipath propagation. The main reason for the absence of a rich multipath propagation is because the millimeter wave wireless channel requires high-gain directive antennas that compensate for the path loss. These directive antennas act as spatial filters, thereby effectively reducing the number of significant multipath components. All the cases presented in this thesis are characterized by one or two dominant multipath components. Small-scale fading is hence adequately modeled with a model named two-wave with diffuse power (TWDP). This TWDP model captures the effect of interference of two non-fluctuating radio signals and of many smaller so-called diffuse signals. A delay-Doppler analysis is also performed in this research based on the data obtained from the vehicular measurement campaign. The analysis reveals that the high maximum Doppler shift is not reflected in the Doppler spread values. Again, the effects of the Doppler shift in this setup are suppressed due to spatial filtering. Lastly, this thesis briefly addresses the modeling of the TWDP model parameters for a simplified railway communications scenario, and demonstrates the implications of TWDP fading through numerical simulations.
... Doppler spectra of vehicle-to-infrastructure (V2I) measurements at 28 GHz in an expressway environment are shown in [13]. Doppler spectra of vibrations appearing while the vehicle is in operation are shown in [14] and [15]. ...
... Doppler spectra of vehicle-to-infrastructure (V2I) measurements at 28 GHz in an expressway environment are shown in [13]. Doppler spectra of vibrations appearing while the vehicle is in operation are shown in [14] and [15]. ...
Preprint
We report results from millimeter wave vehicle-to-infrastructure (V2I) channel measurements conducted on Sept. 25, 2018 in an urban street environment, down-town Vienna, Austria. Measurements of a frequency-division multiplexed multiple-input single-output channel have been acquired with a time-domain channel sounder at 60 GHz with a bandwidth of 100 MHz and a frequency resolution of 5 MHz. Two horn antennas were used on a moving transmitter vehicle: one horn emitted a beam towards the horizon and the second horn emitted an elevated beam at 15-degrees up-tilt. This configuration was chosen to assess the impact of beam elevation on V2I communication channel characteristics: propagation loss and sparsity of the local scattering function in the delay-Doppler domain. The measurement results within urban speed limits show high sparsity in the delay-Doppler domain.
... In [43], 73 GHz V2V large-scale fading and small-scale fading analysis is provided for approaching vehicles. Intra-vehicular Doppler spectra of vibrations appearing while the vehicle is in operation are shown in [44], [45]. In [46], signal-tonoise ratio (SNR) fluctuations for 60 GHz transmissions with 5 MHz bandwidth in a vehicle-to-infrastructure scenario are investigated. ...
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With this essential guide to vehicular networking, you will learn about everything from conceptual approaches and state-of-the-art protocols, to system designs and their evaluation. Covering both in- and inter-vehicle communication, this comprehensive work outlines the foundations of vehicular networking as well as demonstrating its commercial applications, from improved vehicle performance, to entertainment, and traffic information systems. All of this is supported by in-depth case studies and detailed information on proposed protocols and solutions for access technologies and information dissemination, as well as topics on rulemaking, regulations, and standardization. Importantly, for a field which is attracting increasing commercial interest, you will learn about the future trends of this technology, its problems, and solutions to overcome them. Whether you are a student, a communications professional or a researcher, this is an invaluable resource.
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  • M Schack
  • J Jemai
  • R Picsiewicz
  • R Geise
  • I Schmidt
  • T Kurner
In-vehicle channel measurement, characterization, and spatial consistency comparison of 3–11 GHz and 55–65 GHz frequency bands
  • J Blumenstein
  • A Prokes
  • A Chandra
  • T Mikulasek
  • R Marsalek
  • T Zemen
  • C Mecklenbruker
Frequency-domain in-vehicle UWB channel modeling
  • A Chandra
  • A Prokes
  • T Mikulek
  • J Blumenstein
  • P Kukolev
  • T Zemen
Simulation and measurement-based vehicle-to-vehicle channel characterization: Accuracy and constraint analysis
  • T Abbas
  • J Nuckelt
  • T Krner
  • T Zemen
  • C F Mecklenbruker
  • F Tufvesson