1,587 research outputs found
Towards an LTE hybrid unicast broadcast content delivery framework
The era of ubiquitous access to a rich selection of interactive and high quality multimedia has begun; with it,
significant challenges in data demand have been placed on mobile network technologies. Content creators and broadcasters alike have embraced the additional capabilities offered by network delivery; diversifying content offerings and providing viewers with far greater choice. Mobile broadcast services introduced as part of the Long Term Evolution (LTE) standard, that are to be further enhanced with the release of 5G, do aid in spectrally efficient delivery of popular live multimedia to many mobile devices, but, ultimately rely on all users expressing interest in the same single stream. The research presented herein explores the development of a standards aligned, multi-stream aware framework; allowing mobile network operators the efficiency gains of broadcast whilst continuing to offer personalised experiences to subscribers. An open source, system level simulation platform is extended to support broadcast, characterised and validated. This is followed by the implementation of a Hybrid Unicast Broadcast Synchronisation (HUBS) framework able to dynamically vary broadcast resource allocation. The HUBS framework is then
further expanded to make use of scalable video content
CellTV - on the Benefit of TV Distribution over Cellular Networks A Case Study
As mobile IP-access is becoming the dominant technology for providing
wireless services, the demand for more spectrum for this type of access is
increasing rapidly. Since IP-access can be used for all types of services,
instead of a plethora of dedicated, single-service systems, there is a
significant potential to make spectrum use more efficient. In this paper, the
feasibility and potential benefit of replacing the current terrestrial UHF TV
broadcasting system with a mobile, cellular data (IP-) network is analyzed. In
the cellular network, TV content would be provided as {one} of the services,
here referred to as CellTV. In the investigation we consider typical Swedish
rural and urban environments. We use different models for TV viewing patterns
and cellular technologies as expected in the year 2020. Results of the
quantitative analysis indicate that CellTV distribution can be beneficial if
the TV consumption trend goes towards more specialized programming, more local
contents, and more on-demand requests. Mobile cellular systems, with their
flexible unicast capabilities, will be an ideal platform to provide these
services. However, the results also demonstrate that CellTV is not a
spectrum-efficient replacement for terrestrial TV broadcasting with current
viewing patterns (i.e. a moderate number of channels with each a high numbers
of viewers). In this case, it is doubtful whether the expected spectrum savings
can motivate the necessary investments in upgrading cellular sites and
developing advanced TV receiver required for the success of CellTV
distribution.Comment: To appear on Trans. Broadcasting 201
Network Convergence in Multicarrier Hybrid Cellular Network
In a multicarrier communication system with known channel state information at transmitter (CSIT), it is well-known that the water-filling power allocation scheme is optimal in achieving the Shannon capacity. However, in a multicarrier broadcast network (e.g. over-the-air TV network) without CSIT, the optimal power allocation among subcarriers is still unknown, largely due to the heterogeneity of the channel conditions associated with different receivers. In the first part of the thesis, the performance of a generic multicarrier broadcast network is thoroughly studied by exploiting the frequency diversity over subcarriers. In particular, the performance metric is first defined based on the relationship among broadcast transmission rate, coverage area and outage probability. In order to maximize the network performance, closed form expressions of the instantaneous mutual information (IMI) and the optimal power allocation schemes are derived for both low SNR and high SNR cases; upper and lower bounds are also provided to estimate broadcast coverage area in general SNR regime. Also we extend our discussion to the broadcast network with multiple collaborative transmitters. Extensive simulation results are provided to validate our analysis. In the second part of the thesis, we discuss the optimal performance of a generic broadcast cellular hybrid network. It is well known that the Dirty Paper Coding (DPC) achieves the channel capacity for multiuser degraded channels. However, the optimality of DPC remains unknown for non-degraded channel. Specifically, we derive the optimal interference pre-cancellation order for a DPC based broadcast and unicast hybrid network. Different DPC cancellation schemes are studied to maximize the hybrid capacity region. The conditions for each scheme being optimal are analytically derived. Both ergodic and outage capacity are considered as our performance metric. Our results show that the optimal interference pre-cancellation order varies with SNR and broadcast and unicast channel conditions. Moreover, in low SNR condition, the optimal power allocation scheme is derived to reach the maximal sum rate
Demonstrating Immersive Media Delivery on 5G Broadcast and Multicast Testing Networks
This work presents eight demonstrators and one showcase developed within the
5G-Xcast project. They experimentally demonstrate and validate key technical
enablers for the future of media delivery, associated with multicast and
broadcast communication capabilities in 5th Generation (5G). In 5G-Xcast, three
existing testbeds: IRT in Munich (Germany), 5GIC in Surrey (UK), and TUAS in
Turku (Finland), have been developed into 5G broadcast and multicast testing
networks, which enables us to demonstrate our vision of a converged 5G
infrastructure with fixed and mobile accesses and terrestrial broadcast,
delivering immersive audio-visual media content. Built upon the improved
testing networks, the demonstrators and showcase developed in 5G-Xcast show the
impact of the technology developed in the project. Our demonstrations
predominantly cover use cases belonging to two verticals: Media & Entertainment
and Public Warning, which are future 5G scenarios relevant to multicast and
broadcast delivery. In this paper, we present the development of these
demonstrators, the showcase, and the testbeds. We also provide key findings
from the experiments and demonstrations, which not only validate the technical
solutions developed in the project, but also illustrate the potential technical
impact of these solutions for broadcasters, content providers, operators, and
other industries interested in the future immersive media delivery.Comment: 16 pages, 22 figures, IEEE Trans. Broadcastin
On Content-centric Wireless Delivery Networks
The flux of social media and the convenience of mobile connectivity has
created a mobile data phenomenon that is expected to overwhelm the mobile
cellular networks in the foreseeable future. Despite the advent of 4G/LTE, the
growth rate of wireless data has far exceeded the capacity increase of the
mobile networks. A fundamentally new design paradigm is required to tackle the
ever-growing wireless data challenge.
In this article, we investigate the problem of massive content delivery over
wireless networks and present a systematic view on content-centric network
design and its underlying challenges. Towards this end, we first review some of
the recent advancements in Information Centric Networking (ICN) which provides
the basis on how media contents can be labeled, distributed, and placed across
the networks. We then formulate the content delivery task into a content rate
maximization problem over a share wireless channel, which, contrasting the
conventional wisdom that attempts to increase the bit-rate of a unicast system,
maximizes the content delivery capability with a fixed amount of wireless
resources. This conceptually simple change enables us to exploit the "content
diversity" and the "network diversity" by leveraging the abundant computation
sources (through application-layer encoding, pushing and caching, etc.) within
the existing wireless networks. A network architecture that enables wireless
network crowdsourcing for content delivery is then described, followed by an
exemplary campus wireless network that encompasses the above concepts.Comment: 20 pages, 7 figures,accepted by IEEE Wireless
Communications,Sept.201
Rate-Splitting Multiple Access for 6G Networks: Ten Promising Scenarios and Applications
In the upcoming 6G era, multiple access (MA) will play an essential role in
achieving high throughput performances required in a wide range of wireless
applications. Since MA and interference management are closely related issues,
the conventional MA techniques are limited in that they cannot provide
near-optimal performance in universal interference regimes. Recently,
rate-splitting multiple access (RSMA) has been gaining much attention. RSMA
splits an individual message into two parts: a common part, decodable by every
user, and a private part, decodable only by the intended user. Each user first
decodes the common message and then decodes its private message by applying
successive interference cancellation (SIC). By doing so, RSMA not only embraces
the existing MA techniques as special cases but also provides significant
performance gains by efficiently mitigating inter-user interference in a broad
range of interference regimes. In this article, we first present the
theoretical foundation of RSMA. Subsequently, we put forth four key benefits of
RSMA: spectral efficiency, robustness, scalability, and flexibility. Upon this,
we describe how RSMA can enable ten promising scenarios and applications along
with future research directions to pave the way for 6G.Comment: 17 pages, 6 figures, submitted to IEEE Network Magazin
5G New Radio for Terrestrial Broadcast: A Forward-Looking Approach for NR-MBMS
"© 2019 IEEE. Personal use of this material is permitted. Permissíon from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertisíng or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works."[EN] 3GPP LTE eMBMS release (Rel-) 14, also referred to as further evolved multimedia broadcast multicast service (FeMBMS) or enhanced TV (EnTV), is the first mobile broadband technology standard to incorporate a transmission mode designed to deliver terrestrial broadcast services from conventional high power high tower (HPHT) broadcast infrastructure. With respect to the physical layer, the main improvements in FeMBMS are the support of larger inter-site distance for single frequency networks (SFNs) and the ability to allocate 100% of a carrier's resources to the broadcast payload, with self-contained signaling in the downlink. From the system architecture perspective, a receive-only mode enables free-to-air (FTA) reception with no need for an uplink or SIM card, thus receiving content without user equipment registration with a network. These functionalities are only available in the LTE advanced pro specifications as 5G new radio (NR), standardized in 3GPP from Rel-15, has so far focused entirely on unicast. This paper outlines a physical layer design for NR-MBMS, a system derived, with minor modifications, from the 5G-NR specifications, and suitable for the transmission of linear TV and radio services in either single-cell or SFN operation. This paper evaluates the NR-MBMS proposition and compares it to LTE-based FeMBMS in terms of flexibility, performance, capacity, and coverage.This work was supported in part by the European Commission through the 5G-PPP Project 5G-Xcast (H2020-ICT-2016-2 call) under Grant 761498.Gimenez, JJ.; Carcel, JL.; Fuentes, M.; Garro, E.; Elliott, S.; Vargas, D.; Menzel, C.... (2019). 5G New Radio for Terrestrial Broadcast: A Forward-Looking Approach for NR-MBMS. IEEE Transactions on Broadcasting. 65(2):356-368. https://doi.org/10.1109/TBC.2019.291211735636865
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