58 research outputs found
Transmission of multiple description and layered video over an EGPRS wireless network
We investigate the ability of multiple descriptions (MD) and layered coding to improve the quality of video transmitted over EGPRS networks. One-layer video sent over a single channel on such a network has a fairly sharp quality transition, depending on a user’s location. Either the video can be transmitted reliably (if the video rate is less than or equal to what the channel can sustain), or it is subjected to many lost packets. In this system, MD and layered video may offer two ways to improve video quality beyond that of the one-layer video. First, each sub-stream can be sent on a separate channel, essentially doubling the assigned bandwidth and increasing video quality. Second, MD and layered video are more error resilient than one-layer video, potentially improving the video quality seen by users in poor locations. We find that for the system scenarios considered, one- and two-layer coding outperform MD coding, depending upon the number of wireless channels used for the video transport. 1
Recommended from our members
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
Quality of service and resource management in IP and wireless networks
A common theme in the publications included in this thesis is the quality of service and resource management in IP and wireless networks. This thesis presents novel algorithms and implementations for admission control in IP and IEEE 802.16e networks, active queue management in EGPRS, WCDMA, and IEEE 802.16e networks, and scheduling in IEEE 802.16e networks. The performance of different algorithms and mechanisms is compared with the prior art through extensive ns-2 simulations.
We show that similar active queue management mechanisms, such as TTLRED, can be successfully used to reduce the downlink delay (and in some cases even improve the TCP goodput) in different bottlenecks of IP, EGPRS, WCDMA, and IEEE 802.16e access networks. Moreover, almost identical connection admission control algorithms can be applied both in IP access networks and at IEEE 802.16e base stations. In the former case, one just has to first gather the link load information from the IP routers.
We also note that DiffServ can be used to avoid costly overprovisioning of the backhaul in IEEE 802.16e networks. We present a simple mapping between IEEE 802.16e data delivery services and DiffServ traffic classes, and we propose that IEEE 802.16e base stations should take the backhaul traffic load into account in their admission control decisions.
Moreover, different IEEE 802.16e base station scheduling algorithms and uplink channel access mechanisms are studied. In the former study, we show that proportional fair scheduling offers superior spectral efficiency when compared to deficit round-robin, though in some cases at the cost of increased delay. Additionally, we introduce a variant of deficit round-robin (WDRR), where the quantum value depends on the modulation and coding scheme.
We also show that there are several ways to implement ertPS in an efficient manner, so that during the silence periods of a VoIP call no uplink slots are granted. The problem here, however, is how to implement the resumption after the silence period while introducing as little delay as possible
User interface of a GSM capacity optimisation tool
Kapasiteettivaatimukset moderneissa matkapuhelinverkoissa, kuten GSM/EDGE, kasvavat koko ajan johtuen lisääntyvästä datapalveluiden käytöstä. Näkyvyyden puute mahdollisissa kapasiteettiongelmissa eri BSS:n alueen pullonkauloissa, mukaan lukien Radio, Abis/EDAP, PCU ja Gb-rajapinnat, saattavat aiheuttaa ongelmia koko verkon suorituskyvylle.
Keskitetty ratkaisu, jolla voidaan analysoida ja optimoida erilaisia verkon kapasiteettialueita perustuen verkon oikeisiin mittauksiin, lisäisi näkyvyyttä koko verkon yli tapahtuvassa kapasiteettianalyysissä. Koko verkkoa tutkittaessa pitää myös olla mahdollista syventää yksittäisen osa-alueen analyysia. Mittausten perusteella voidaan luoda sääntöjä, joilla helpotetaan ongelmien tunnistamista ja korjausta.
Käyttäjän tarpeiden ja tavoitteiden ymmärtäminen ja hyväksyminen auttaa käyttäjävaatimusten luonnissa. Tässä diplomityössä on kuvattu käyttäjävaatimuksia GSM/EDGE-verkkojen kapasiteettianalyysiin liittyviin tarpeisiin Nokia Siemens Networksin OSS:ssä. Vaatimuksista voidaan koota tehtävänkuvauksia, jotka auttavat muuten huomaamatta jäävien käyttäjävaatimusten tunnistamisessa.
Tämän diplomityön tärkein anti liittyy monimutkaisen kokoonpano- ja suorituskykytiedon visualisointiin. Tällaisen tiedon visualisointi vaatii useita eri esitystapoja. Looginen verkkorakenne vaatii puumaisen rakenteen, jolla voidaan kuvata verkkoelementtien välisiä riippuvuuksia. Tarvitaan myös tapa kuvata maantieteellinen informaatio ja mittausdata samassa näkymässä. Lisäksi tarvitaan keino visualisoida tarkempaa kokoonpano- ja suorituskykytietoa taulukkorakenteena tekstimuodossa. Nämä tarpeet ja toiminnallisuudet kumpuavat käyttäjän tarpeista eri kapasiteettianalyysin osa-alueilla. Erityisesti suunnittelussa on huomioitu eri näkymien välinen yhteistoiminta, jonka tulee tukea koko kapasiteettianalyysiä. Suunnittelussa on painotettu myös mahdollisia tulevaisuuden laajennuskohteita kuten runkoverkko, WCDMA, WiMax sekä muiden valmistajien verkkoratkaisut.The capacity requirements for modern mobile networks build on top of technology like GSM/EDGE are increasing as the usage of data services is growing. The lack of visibility of possible problems in bottlenecks in the BSS domain, including Radio, Abis/EDAP, PCU and Gb-interface, can cause degradation to the whole network capacity throughput.
A centralised solution to analyse and optimise the different network domains through real network measurement would increase the visibility of the overall edge-to-edge chain of capacity network. From this edge-to-edge analysis, a drilldown further to the actual root cause is also needed. Based on the measurements particular rules can be created for each domain that can help in identifying and correcting the actual problems.
Understanding and accepting the user goals and needs help in the creation of user requirements. In this thesis, the user requirements for GSM/EDGE capacity related needs for Nokia Siemens Networks OSS are described. The user requirements can be used to create workflows that can identify gaps related to individual user requirements.
The main contribution of this thesis is to clarify issues related to visualisation of complex data associated to configuration and performance management of the network. This requires many different visualisation channels. Logical network structure requires a tree-like view to be able to visualise relationships between different network elements. A view to present geographical information and performance data related to the network elements on map is also needed. The last visualisation channel required needs to present configuration and performance attribute related information in a table like form. The needs and functions of all these views are derived from the user needs related to capacity analysis in different domains. The main emphasis of different views is in the inter-working functions to support the overall workflow of capacity optimisation. The expandability of the solution should also be stressed to allow future capacity network analysis domains like core network, WCDMA and WiMax and even other vendors besides Nokia Siemens Networks
Network-coded NOMA with antenna selection for the support of two heterogeneous groups of users
The combination of Non-Orthogonal Multiple Access (NOMA) and Transmit Antenna Selection (TAS) techniques
has recently attracted significant attention due to the low cost,
low complexity and high diversity gains. Meanwhile, Random
Linear Coding (RLC) is considered to be a promising technique
for achieving high reliability and low latency in multicast
communications. In this paper, we consider a downlink system
with a multi-antenna base station and two multicast groups of
single-antenna users, where one group can afford to be served
opportunistically, while the other group consists of comparatively
low power devices with limited processing capabilities that have
strict Quality of Service (QoS) requirements. In order to boost
reliability and satisfy the QoS requirements of the multicast
groups, we propose a cross-layer framework including NOMAbased TAS at the physical layer and RLC at the application
layer. In particular, two low complexity TAS protocols for NOMA
are studied in order to exploit the diversity gain and meet the
QoS requirements. In addition, RLC analysis aims to facilitate
heterogeneous users, such that, sliding window based sparse RLC
is employed for computational restricted users, and conventional
RLC is considered for others. Theoretical expressions that
characterize the performance of the proposed framework are
derived and verified through simulation results
An intelligent-agent approach for managing congestion in W-CDMA networks
PhDResource Management is a crucial aspect in the next generation cellular networks
since the use of W-CDMA technology gives an inherent flexibility in managing the
system capacity. The concept of a “Service Level Agreement” (SLA) also plays a
very important role as it is the means to guarantee the quality of service provided to
the customers in response to the level of service to which they have subscribed.
Hence there is a need to introduce effective SLA-based policies as part of the radio
resource management.
This work proposes the application of intelligent agents in SLA-based control in
resource management, especially when congestion occurs. The work demonstrates the
ability of intelligent agents in improving and maintaining the quality of service to
meet the required SLA as the congestion occurs.
A particularly novel aspect of this work is the use of learning (here Case Based
Reasoning) to predict the control strategies to be imposed. As the system environment
changes, the most suitable policy will be implemented. When congestion occurs, the
system either proposes the solution by recalling from experience (if the event is
similar to what has been previously solved) or recalculates the solution from its
knowledge (if the event is new). With this approach, the system performance will be
monitored at all times and a suitable policy can be immediately applied as the system
environment changes, resulting in maintaining the system quality of service
Joint coding/decoding techniques and diversity techniques for video and HTML transmission over wireless point/multipoint: a survey
I. Introduction
The concomitant developments of the Internet, which offers to its users always larger and more evolved contents (from
HTML (HyperText Markup Language) files to multimedia applications), and of wireless systems and handhelds integrating
them, have progressively convinced a fair share of people of the interest to always be connected. Still, constraints of
heterogeneity, reliability, quality and delay over the transmission channels are generally imposed to fulfill the
requirements of these new needs and their corresponding economical goals. This implies different theoretical and
practical challenges for the digital communications community of the present time.
This paper presents a survey of the different techniques existing in the domain of HTML and video stream transmission
over erroneous or lossy channels. In particular, the existing techniques on joint source and channel coding and decoding
for multimedia or HTML applications are surveyed, as well as the related problems of streaming and downloading files
over an IP mobile link. Finally, various diversity techniques that can be considered for such links, from antenna diversity
to coding diversity, are presented...L’engouement du grand public pour les applications multimédia sans fil ne cesse de croître depuis
le développement d’Internet. Des contraintes d’hétérogénéité de canaux de transmission, de fiabilité,
de qualité et de délai sont généralement exigées pour satisfaire les nouveaux besoins applicatifs entraînant
ainsi des enjeux économiques importants. À l’heure actuelle, il reste encore un certain nombre de défis
pratiques et théoriques lancés par les chercheurs de la communauté des communications numériques. C’est
dans ce cadre que s’inscrit le panorama présenté ici.
Cet article présente d’une part un état de l’art sur les principales techniques de codage et de décodage
conjoint développées dans la littérature pour des applications multimédia de type téléchargement et diffusion
de contenu sur lien mobile IP. Sont tout d’abord rappelées des notions fondamentales des communications
numériques à savoir le codage de source, le codage de canal ainsi que les théorèmes de Shannon et leurs
principales limitations. Les techniques de codage décodage conjoint présentées dans cet article concernent
essentiellement celles développées pour des schémas de codage de source faisant intervenir des codes
à longueur variable (CLV) notamment les codes d’Huffman, arithmétiques et les codes entropiques universels
de type Lempel-Ziv (LZ). Faisant face au problème de la transmission de données (Hypertext Markup
Language (HTML) et vidéo) sur un lien sans fil, cet article présente d’autre part un panorama de techniques de diversités plus ou moins complexes en vue d’introduire le nouveau
système à multiples antennes d’émission et de réception
Cost based optimization for strategic mobile radio access network planning using metaheuristics
La evoluciĂłn experimentada por las comunicaciones mĂłviles a lo largo de las Ăşltimas
décadas ha sido motivada por dos factores principales: el surgimiento de nuevas aplicaciones
y necesidades por parte del usuario, asĂ como los avances tecnolĂłgicos. Los
servicios ofrecidos para términales móviles han evolucionado desde el clásico servicio
de voz y mensajes cortos (SMS), a servicios más atractivos y por lo tanto con una
rápida aceptación por parte de usuario final como, video telephony, video streaming,
online gaming, and the internet broadband access (MBAS). Todos estos nuevos servicios
se han convertido en una realidad gracias a los avances técnologicos, avances
tales como nuevas técnicas de acceso al medio compartido, nuevos esquemas de codificiación
y modulaciĂłn de la informaciĂłn intercambiada, sistemas de transmisiĂłn y
recepciĂłn basados en mĂşltiples antenas (MIMO), etc.
Un aspecto importante en esta evoluciĂłn fue la liberaciĂłn del sector a principios de
los años 90, donde la función reguladora llevado a cabo por las autoridades regulatorias
nacionales (NRA) se ha antojado fundamental. Uno de los principales problemas
tratados por la NRA espcĂfica de cada naciĂłn es la determinaciĂłn de los costes por
servicios mayoristas, esto es los servicios entre operadores de servicios mĂłvilles, entre
los que cabe destacar el coste por terminaciĂłn de llamada o de inteconexiĂłn. El
servicio de interconexiĂłn hace posible la comunicaciĂłn de usuarios de diferente operadores,
asĂ como el acceso a la totalidad de servicios, incluso a aquellos no prestados
por un operador en concreto gracias al uso de una red perteneciente a otro operador,
por parte de todos los usuarios.
El objetivo principal de esta tesis es la minimizaciĂłn de los costes de inversiĂłn en
equipamiento de red, lo cual repercute en el establecimiento de las tarifas de interconexiĂłn
como se verá a lo largo de este trabajo. La consecución de dicho objetivo
se divide en dos partes: en primer lugar, el desarrollo de un conjunto de algoritmos
para el dimesionado Ăłptimo de una red de acceso radio (RAN) para un sistema de
comunicaciones móvilles. En segundo lugar, el diseño y aplicación de algoritmos de
optimizaciĂłn para la distribuciĂłn Ăłptima de los servicios sobre el conjunto de tecnologĂas
mĂłviles existentes (OSDP).
El modulo de diseño de red proporciona cuatro algoritmos diferenciados encargados
del dimensionado y planificaciĂłn de la red de acceso mĂłvil. Estos algoritmos se aplican
en un entorno multi-tecnologĂa, considerando sistemas de segunda (2G), tercera
(3G) y cuarta (4G) generaciĂłn, multi-usuario, teniendo en cuenta diferentes perfiles
de usuarios con su respectiva carga de tráfico, y multo-servicio, incluyendo voz, servicios
de datos de baja velocidad (64-144 Kbps), y acceso a internet de banda ancha
mĂłvil.
La segunda parte de la tesis se encarga de distribuir de una manera Ăłptima el conjunto
de servicios sobre las tecnologĂas a desplegar. El objetivo de esta parte es
hacer un uso eficiente de las tecnologĂas existentes reduciendo los costes de inversiĂłn
en equipamiento de red. Esto es posible gracias a las diferencias tecnolĂłgicas existente
entre los diferentes sistemas mĂłviles, que hacen que los sistemas de segunda
generaciĂłn sean adecuados para proporcionar el servicio de voz y mensajerĂa corta,
mientras que redes de tercera generaciĂłn muestran un mejor rendimiento en la transmisiĂłn
de servicios de datos. Por Ăşltimo, el servicio de banda ancha mĂłvil es nativo
de redes de Ăşltima generadĂłn, como High Speed Data Acces (HSPA) y 4G.
Ambos mĂłdulos han sido aplicados a un extenso conjunto de experimentos para el
desarrollo de análisis tecno-económicos tales como el estudio del rendimiento de las
tecnologĂas de HSPA y 4G para la prestaciĂłn del servicio de banda ancha mĂłvil, asĂ
como el análisis de escenarios reales de despliegue para redes 4G que tendrán lugar a
partir del próximo año coinicidiendo con la licitación de las frecuencias en la banda
de 800 MHz. AsĂ mismo, se ha llevado a cabo un estudio sobre el despliegue de redes
de 4G en las bandas de 800 MHz, 1800 MHz y 2600 MHz, comparando los costes
de inversiĂłn obtenidos tras la optimizaciĂłn. En todos los casos se ha demostrado
la mejora, en términos de costes de inversión, obtenida tras la aplicación de ambos
mĂłdulos, posibilitando una reducciĂłn en la determinaciĂłn de los costes de provisiĂłn
de servicios.
Los estudios realizados en esta tesis se centran en la nación de España, sin embargo
todos los algoritmos implementados son aplicables a cualquier otro paĂs europeo,
prueba de ello es que los algoritmos de diseño de red han sido utilizados en diversos
proyectos de regulaciĂłn
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