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Multimedia delivery in the future internet
The term “Networked Media” implies that all kinds of media including text, image, 3D graphics, audio
and video are produced, distributed, shared, managed and consumed on-line through various networks,
like the Internet, Fiber, WiFi, WiMAX, GPRS, 3G and so on, in a convergent manner [1]. This white
paper is the contribution of the Media Delivery Platform (MDP) cluster and aims to cover the Networked
challenges of the Networked Media in the transition to the Future of the Internet.
Internet has evolved and changed the way we work and live. End users of the Internet have been confronted
with a bewildering range of media, services and applications and of technological innovations concerning
media formats, wireless networks, terminal types and capabilities. And there is little evidence that the pace
of this innovation is slowing. Today, over one billion of users access the Internet on regular basis, more
than 100 million users have downloaded at least one (multi)media file and over 47 millions of them do so
regularly, searching in more than 160 Exabytes1 of content. In the near future these numbers are expected
to exponentially rise. It is expected that the Internet content will be increased by at least a factor of 6, rising
to more than 990 Exabytes before 2012, fuelled mainly by the users themselves. Moreover, it is envisaged
that in a near- to mid-term future, the Internet will provide the means to share and distribute (new)
multimedia content and services with superior quality and striking flexibility, in a trusted and personalized
way, improving citizens’ quality of life, working conditions, edutainment and safety.
In this evolving environment, new transport protocols, new multimedia encoding schemes, cross-layer inthe
network adaptation, machine-to-machine communication (including RFIDs), rich 3D content as well as
community networks and the use of peer-to-peer (P2P) overlays are expected to generate new models of
interaction and cooperation, and be able to support enhanced perceived quality-of-experience (PQoE) and
innovative applications “on the move”, like virtual collaboration environments, personalised services/
media, virtual sport groups, on-line gaming, edutainment. In this context, the interaction with content
combined with interactive/multimedia search capabilities across distributed repositories, opportunistic P2P
networks and the dynamic adaptation to the characteristics of diverse mobile terminals are expected to
contribute towards such a vision.
Based on work that has taken place in a number of EC co-funded projects, in Framework Program 6 (FP6)
and Framework Program 7 (FP7), a group of experts and technology visionaries have voluntarily
contributed in this white paper aiming to describe the status, the state-of-the art, the challenges and the way
ahead in the area of Content Aware media delivery platforms
5G 3GPP-like Channel Models for Outdoor Urban Microcellular and Macrocellular Environments
For the development of new 5G systems to operate in bands up to 100 GHz,
there is a need for accurate radio propagation models at these bands that
currently are not addressed by existing channel models developed for bands
below 6 GHz. This document presents a preliminary overview of 5G channel models
for bands up to 100 GHz. These have been derived based on extensive measurement
and ray tracing results across a multitude of frequencies from 6 GHz to 100
GHz, and this document describes an initial 3D channel model which includes: 1)
typical deployment scenarios for urban microcells (UMi) and urban macrocells
(UMa), and 2) a baseline model for incorporating path loss, shadow fading, line
of sight probability, penetration and blockage models for the typical
scenarios. Various processing methodologies such as clustering and antenna
decoupling algorithms are also presented.Comment: To be published in 2016 IEEE 83rd Vehicular Technology Conference
Spring (VTC 2016-Spring), Nanjing, China, May 201
Massive MIMO Extensions to the COST 2100 Channel Model: Modeling and Validation
To enable realistic studies of massive multiple-input multiple-output
systems, the COST 2100 channel model is extended based on measurements. First,
the concept of a base station-side visibility region (BS-VR) is proposed to
model the appearance and disappearance of clusters when using a
physically-large array. We find that BS-VR lifetimes are exponentially
distributed, and that the number of BS-VRs is Poisson distributed with
intensity proportional to the sum of the array length and the mean lifetime.
Simulations suggest that under certain conditions longer lifetimes can help
decorrelating closely-located users. Second, the concept of a multipath
component visibility region (MPC-VR) is proposed to model birth-death processes
of individual MPCs at the mobile station side. We find that both MPC lifetimes
and MPC-VR radii are lognormally distributed. Simulations suggest that unless
MPC-VRs are applied the channel condition number is overestimated. Key
statistical properties of the proposed extensions, e.g., autocorrelation
functions, maximum likelihood estimators, and Cramer-Rao bounds, are derived
and analyzed.Comment: Submitted to IEEE Transactions of Wireless Communication
A Generalized Spatial Correlation Model for 3D MIMO Channels based on the Fourier Coefficients of Power Spectrums
Previous studies have confirmed the adverse impact of fading correlation on
the mutual information (MI) of two-dimensional (2D) multiple-input
multiple-output (MIMO) systems. More recently, the trend is to enhance the
system performance by exploiting the channel's degrees of freedom in the
elevation, which necessitates the derivation and characterization of
three-dimensional (3D) channels in the presence of spatial correlation. In this
paper, an exact closed-form expression for the Spatial Correlation Function
(SCF) is derived for 3D MIMO channels. This novel SCF is developed for a
uniform linear array of antennas with nonisotropic antenna patterns. The
proposed method resorts to the spherical harmonic expansion (SHE) of plane
waves and the trigonometric expansion of Legendre and associated Legendre
polynomials. The resulting expression depends on the underlying arbitrary
angular distributions and antenna patterns through the Fourier Series (FS)
coefficients of power azimuth and elevation spectrums. The novelty of the
proposed method lies in the SCF being valid for any 3D propagation environment.
The developed SCF determines the covariance matrices at the transmitter and the
receiver that form the Kronecker channel model. In order to quantify the
effects of correlation on the system performance, the information-theoretic
deterministic equivalents of the MI for the Kronecker model are utilized in
both mono-user and multi-user cases. Numerical results validate the proposed
analytical expressions and elucidate the dependence of the system performance
on azimuth and elevation angular spreads and antenna patterns. Some useful
insights into the behaviour of MI as a function of downtilt angles are
provided. The derived model will help evaluate the performance of correlated 3D
MIMO channels in the future.Comment: Accepted in IEEE Transactions on signal processin
Integration of Carrier Aggregation and Dual Connectivity for the ns-3 mmWave Module
Thanks to the wide availability of bandwidth, the millimeter wave (mmWave)
frequencies will provide very high data rates to mobile users in next
generation 5G cellular networks. However, mmWave links suffer from high
isotropic pathloss and blockage from common materials, and are subject to an
intermittent channel quality. Therefore, protocols and solutions at different
layers in the cellular network and the TCP/IP protocol stack have been proposed
and studied. A valuable tool for the end-to-end performance analysis of mmWave
cellular networks is the ns-3 mmWave module, which already models in detail the
channel, Physical (PHY) and Medium Access Control (MAC) layers, and extends the
Long Term Evolution (LTE) stack for the higher layers. In this paper we present
an implementation for the ns-3 mmWave module of multi connectivity techniques
for 3GPP New Radio (NR) at mmWave frequencies, namely Carrier Aggregation (CA)
and Dual Connectivity (DC), and discuss how they can be integrated to increase
the functionalities offered by the ns-3 mmWave module.Comment: 9 pages, 7 figures, submitted to the Workshop on ns-3 (WNS3) 201
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