scholarly journals A Wideband Channel Model for Intravehicular Nomadic Systems

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
François Bellens ◽  
François Quitin ◽  
Jean-Michel Dricot ◽  
François Horlin ◽  
Aziz Benlarbi-Delaï ◽  
...  
Keyword(s):  
Channel Model ◽  
Temporal Variations ◽  
Rear Seat ◽  
Base Station ◽  
Ultra Wideband ◽  
Personal Area Networks ◽  
Vehicular Communication ◽  
Single Input Single Output ◽  
Single Output ◽  
Data Rates

The increase in electronic entertainment equipments within vehicles has rendered the idea of replacing the wired links with intra-vehicle personal area networks. Ultra-wideband (UWB) seems an appropriate candidate technology to meet the required data rates for interconnecting such devices. In particular, the multiband OFDM (MB-OFDM) is able to provide very high transfer rates (up to 480 MBps) over relatively short distances and low transmit power. In order to evaluate the performances of UWB systems within vehicles, a reliable channel model is needed. In this paper, a nomadic system where a base station placed in the center of the dashboard wants to communicate with fixed devices placed at the rear seat is investigated. A single-input single-output (SISO) channel model for intra-vehicular communication (IVC) systems is proposed, based on reverberation chamber theory. The model is based on measurements conducted in real traffic conditions, with a varying number of passengers in the car. Temporal variations of the wireless channels are also characterized and parametrized. The proposed model is validated by comparing model-independent statistics with the measurements.

scholarly journals 3GPP Channel Model Emulation with Analysis of MIMO-LTE Performances in Reverberation Chamber

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Nabil Arsalane ◽  
Moctar Mouhamadou ◽  
Cyril Decroze ◽  
David Carsenat ◽  
Miguel Angel Garcia-Fernandez ◽  
...  
Keyword(s):  
Channel Model ◽  
Reference Case ◽  
Reverberation Chamber ◽  
Single Input Single Output ◽  
Single Output ◽  
Received Power ◽  
Communication Devices ◽  
Set Up ◽  
Multiple Clusters ◽  
Active Link

Emulation methodology of multiple clusters channels for evaluating wireless communication devices over-the-air (OTA) performance is investigated. This methodology has been used along with the implementation of the SIMO LTE standard. It consists of evaluating effective diversity gain (EDG) level of SIMO LTE-OFDM system for different channel models according to the received power by establishing an active link between the transmitter and the receiver. The measurement process is set up in a Reverberation Chamber (RC). The obtained results are compared to the reference case of single input-single output (SISO) in order to evaluate the real improvement attained by the implemented system.

scholarly journals Network Optimization Using Femtocell Deployment at Macrocell Edge in Cognitive Environment

2021 ◽  
Author(s):  
Joydev Ghosh
Keyword(s):  
Base Station ◽  
Wall Structure ◽  
Matlab Simulation ◽  
Femtocell Networks ◽  
Single Input Single Output ◽  
Cell Edge ◽  
Single Output ◽  
Macro Cell ◽  
Performance Metric ◽  
Cognitive Environment

<div>This research focuses on the problem of cell edge user’s coverage in the context of femtocell networks operating within the locality of macrocell border where pathloss, shadowing, Rayleigh fading have been included into the environment. As macro cell edge users are located far-away from the macro base station (MBS), so that, the underprivileged users (cell edge users) get assisted by the cognitive-femto base station (FBS) to provide consistent quality of service (QoS). Considering various environment factors such as wall structure, number of walls, distance between MBS and users, interference effect (i.e., co-tier and cross-tier), we compute downlink (DL) throughput of femto user (FU) for single input single output (SISO) system over a particular sub-channel, but also based on spectrum allocation and power adaptation, performance</div><div>of two tier network is analyzed considering network coverage as the performance metric. Finally, the effectiveness of the scheme is verified by extensive matlab simulation.</div>

scholarly journals Ergodic Rate for Fading Interference Channels with Proper and Improper Gaussian Signaling

Entropy ◽  
2019 ◽  
Vol 21 (10) ◽  
pp. 922 ◽  
Author(s):  
Mohammad Soleymani ◽  
Ignacio Santamaria ◽  
Christian Lameiro ◽  
Peter J. Schreier
Keyword(s):  
Channel Model ◽  
Time Sharing ◽  
Fixed Rate ◽  
Channel State ◽  
Single Input Single Output ◽  
Transmission Parameters ◽  
Single Output ◽  
Rate Region ◽  
Perfect Channel State Information ◽  
Single Input

This paper studies the performance of improper Gaussian signaling (IGS) over a 2-user Rayleigh single-input single-output (SISO) interference channel, treating interference as noise. We assume that the receivers have perfect channel state information (CSI), while the transmitters have access to only statistical CSI. Under these assumptions, we consider a signaling scheme, which we refer to as proper/improper Gaussian signaling or PGS/IGS, where at most one user may employ IGS. For the Rayleigh fading channel model, we characterize the statistical distribution of the signal-to-interference-plus-noise ratio at each receiver and derive closed-form expressions for the ergodic rates. By adapting the powers, we characterize the Pareto boundary of the ergodic rate region for the 2-user fading IC. The ergodic transmission rates can be attained using fixed-rate codebooks and no optimization is involved. Our results show that, in the moderate and strong interference regimes, the proposed PGS/IGS scheme improves the performance with respect to the PGS scheme. Additionally, we numerically compute the ergodic rate region of the full IGS scheme when both users can employ IGS and their transmission parameters are optimized by an exhaustive search. Our results suggest that most of the Pareto optimal points for the 2-user fading IC channel are attained when either both users transmit PGS or when one transmits PGS and the other transmits maximally improper Gaussian signals and time sharing is allowed.

scholarly journals Cognitive-Femtocell Based Resource Allocation in Macrocell Network

2021 ◽  
Author(s):  
Joydev Ghosh
Keyword(s):  
Base Station ◽  
Base Stations ◽  
Network Coverage ◽  
Femtocell Networks ◽  
Single Input Single Output ◽  
Single Output ◽  
Efficiency Measures ◽  
Input Multiple Output ◽  
Single Input ◽  
Cognitive Femtocell

<div>In this paper, we articulate the network coverage issues for both Femto Users (FUs) and Macro Users (MUs) located at cell edges. The cognitive-femtocell networks functioning under the vicinity of a macrocell frontier where the parameters such as pathloss, shadowing, Rayleigh fading have considered into the system model. The users, located at network border are positioned far apart from the Macro Base Station (MBS). This can be treated as the underprivileged users. The underprivileged users are to be facilitated by the femto cell base stations to provide uninterrupted QoS. We present on the overall outage probability of Single Input single Output (SISO) users and Single Input Multiple Output (SIMO) users, respectively, by taking several circumstantial components such as such as probability density function (PDF), location gap between base stations (BSs) and users, intra-tier interference and inter-tier interference into account. Further, evaluation has been extended by considering network throughput as the efficiency measures based on the sub-carrier and the power allotment in the dual tier network.</div>

scholarly journals A Novel Fairness-Aware Resource Allocation Scheme in Multiuser SISO-OFDMA Downlink

2010 ◽  
Vol 2010 ◽  
pp. 1-10 ◽  
Author(s):  
Vasileios D. Papoutsis ◽  
Ioannis G. Fraimis ◽  
Stavros A. Kotsopoulos
Keyword(s):  
Resource Allocation ◽  
Multiple Access ◽  
Computational Cost ◽  
Wireless Systems ◽  
Base Station ◽  
Proportional Fairness ◽  
Allocation Scheme ◽  
Single Input Single Output ◽  
Data Rates ◽  
Resource Allocation Scheme

The problem of resource allocation for the downlink of wireless systems operating over a frequency-selective channel is investigated. It is assumed that both the Base Station (BS) and each user are equipped with a single antenna (Single Input Single Output-SISO case), and Orthogonal Frequency Division Multiple Access (OFDMA) is used as a multiple access scheme. The aim is to maximize the sum of the users' data rates subject to constraints on total available power and proportional fairness among users' data rates. Achieving the optimal solution has a high computational cost thereby the use of suboptimal techniques is necessary. A suboptimal, but efficient, scheme is devised, and it is shown, via simulation, that not only the proposed resource allocation scheme achieve higher sum of the users' data rates than other existing schemes but also the sum data rate is distributed fairly and flexibly among users. In addition, the proposed scheme is complexity effective and can be applied to latest-generation wireless systems that provide Quality-of-Service (QoS) guarantees.

scholarly journals A Semiempirical MIMO Channel Model in Obstructed Viaduct Scenarios on High-Speed Railway

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Tao Zhou ◽  
Cheng Tao ◽  
Liu Liu ◽  
Zhenhui Tan
Keyword(s):  
High Speed ◽  
Channel Model ◽  
Mimo Systems ◽  
Multiple Input Multiple Output ◽  
Time Correlation ◽  
Time Correlation Function ◽  
Mimo Channel ◽  
High Speed Railway ◽  
Single Input Single Output ◽  
Single Output

A semiempirical multiple-input multiple-output (MIMO) channel model is proposed for high-speed railway (HSR) viaduct scenarios. The proposed MIMO model is based on the combination of realistic single-input single-output (SISO) channel measurement results and a theoretical geometry-based stochastic model (GBSM). Temporal fading characteristics involvingK-factor and Doppler power spectral density (PSD) are derived from the wideband measurement under an obstructed viaduct on Zhengzhou-Xi’an HSR in China. The GBSM composed of a one-ring model and an elliptical model is employed to describe the entire propagation environment. Environment-related parameters in the GBSM are determined by the measured temporal fading properties. And a close agreement is achieved between the model results and measured data. Finally, a deterministic simulation model is established to perform the analysis of the space-time correlation function, the space-Doppler PSD, and the channel capacity for the measured scenario. This model is more realistic and particularly beneficial for the performance evaluation of MIMO systems in HSR environments.

scholarly journals Cognitive-Femtocell Based Resource Allocation in Macrocell Network

2021 ◽  
Author(s):  
Joydev Ghosh
Keyword(s):  
Base Station ◽  
Base Stations ◽  
Network Coverage ◽  
Femtocell Networks ◽  
Single Input Single Output ◽  
Single Output ◽  
Efficiency Measures ◽  
Input Multiple Output ◽  
Single Input ◽  
Cognitive Femtocell

<div>In this paper, we articulate the network coverage issues for both Femto Users (FUs) and Macro Users (MUs) located at cell edges. The cognitive-femtocell networks functioning under the vicinity of a macrocell frontier where the parameters such as pathloss, shadowing, Rayleigh fading have considered into the system model. The users, located at network border are positioned far apart from the Macro Base Station (MBS). This can be treated as the underprivileged users. The underprivileged users are to be facilitated by the femto cell base stations to provide uninterrupted QoS. We present on the overall outage probability of Single Input single Output (SISO) users and Single Input Multiple Output (SIMO) users, respectively, by taking several circumstantial components such as such as probability density function (PDF), location gap between base stations (BSs) and users, intra-tier interference and inter-tier interference into account. Further, evaluation has been extended by considering network throughput as the efficiency measures based on the sub-carrier and the power allotment in the dual tier network.</div>

scholarly journals Performance Improvement of Outage Users at Cell Edges Through Cognitive-Femtocell Deployment Over Macrocell Network

2021 ◽  
Author(s):  
Joydev Ghosh
Keyword(s):  
Base Station ◽  
Wall Structure ◽  
Femtocell Networks ◽  
Long Distance ◽  
Single Input Single Output ◽  
Cell Edge ◽  
Single Output ◽  
Macro Cell ◽  
User Coverage ◽  
Single Input

<div>This research focuses on the problem of cell edge user coverage in the context of femtocell networks operating within the locality of macrocell border. The macro cell-edge users get assisted by the cognitive-femto base station (FBS) to receive a consistent quality of service (QoS) because of their long distance from the macro base station (MBS). Considering various environment factors such as wall structure, number of walls, distance between macrocell and users, interference effect (i.e., co-tier and cross-tier), we compute not only the overall outage probability of single input single output (SISO) system and single input multiple output (SIMO) system users but also based on subcarrier and power allocation the performance of the two tier network is analysed with macrocell throughput as the performance metric. Finally, the effectiveness of the scheme is verified by extensive matlab simulation.</div>

scholarly journals On secure system performance over SISO, MISO and MIMO-NOMA wireless networks equipped a multiple antenna based on TAS protocol

2020 ◽  
Vol 2020 (1) ◽  
Author(s):  
Thanh-Nam Tran ◽  
Miroslav Voznak
Keyword(s):  
Fading Channels ◽  
System Performance ◽  
Interference Cancellation ◽  
Base Station ◽  
System Throughput ◽  
Experimental Investigations ◽  
Single Input Single Output ◽  
Single Antenna ◽  
Single Output ◽  
The Individual

AbstractThis study examined how to improve system performance by equipping multiple antennae at a base station (BS) and all terminal users/mobile devices instead of a single antenna as in previous studies. Experimental investigations based on three NOMA down-link models involved (1) a single-input-single-output (SISO) scenario in which a single antenna was equipped at a BS and for all users, (2) a multi-input-single-output (MISO) scenario in which multiple transmitter antennae were equipped at a BS and a single receiver antenna for all users and (3) a multi-input-multi-output (MIMO) scenario in which multiple transmitter antennae were equipped at a BS and multiple receiver antenna for all users. This study investigated and compared the outage probability (OP) and system throughput assuming all users were over Rayleigh fading channels. The individual scenarios also each had an eavesdropper. Secure system performance of the individual scenarios was therefore also investigated. In order to detect data from superimposed signals, successive interference cancellation (SIC) was deployed for users, taking into account perfect, imperfect and fully imperfect SICs. The results of analysis of users in these three scenarios were obtained in an approximate closed form by using the Gaussian-Chebyshev quadrature method. However, the clearly and accurately presented results obtained using Monte Carlo simulations prove and verify that the MIMO-NOMA scenario equipped with multiple antennae significantly improved system performance.

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