Digital Video Broadcasting Networks Research Articles

Spectral Overlap Optimization for DVB-T2 and LTE Coexistence

In this paper, we analyze the spectral coexistence between the second generation terrestrial digital video broadcasting (DVB) and the long term evolution (LTE) networks. In particular, the global spectral efficiency (SE) of both systems is investigated when a partial spectral overlap between DVB and LTE signals occurs. Our contribution lies in twofold: 1) the interfering signal variance in each network is derived analytically according to the frequency overlap while taking into account the difference between the characteristics of LTE and DVB networks, especially the OFDM subcarrier spacing and then the OFDM symbol duration and 2) SE is derived with uniform and non uniform power allocation between overlapped and non overlapped subcarriers of the two networks. This derivation offers an analytical evaluation of the effect of the spectral overlap ratio variation and different power allocation scenarios and provides insightful results on the cooperation between the two networks.

Adaptive Multiview Video Delivery Using Hybrid Networking

Multiview entertainment is the next step in 3D immersive media networking owing to its improved depth perception and free-viewpoint viewing capability whereby users can observe the scene from the desired viewpoint. This paper outlines a delivery system for multiview plus depth video, combining the broadcast and broadband networks. The digital video broadcast (DVB) network is used along with adaptive peer-to-peer (P2P) distribution over the Internet to deliver high-volume multimedia to users. The DVB network has been used to deliver part of the 3D service, owing to its robustness and wide availability, as a mechanism to guarantee the minimum 3D quality of experience. The developed system brings key contributions in the P2P transport for real-time multimedia delivery, including a user preference-aware adaptation mechanism, adaptive redundant chunk scheduling for robustness, incentives to decrease the load on the content server for improved system scalability, and resynchronization capability with the DVB transmission. The introduced features are compared with those of some other well-known P2P solutions to highlight the quantitative gains. A subjective testing campaign has also been organized on the developed hybrid platform, which proves the effectiveness of user-aware adaptation over network-based adaptation on a mean opinion score scale.

A Survey on Contemporary Terrestrial and Handheld Multimedia Broadcasting Networks

Digital video broadcasting (DVB) transmission technologies are suitable for wireless delivery of multimedia content both to static and mobile end-users. On the one hand, DVB-T standard has been adopted for digital terrestrial television (DTT) and it has been further developed into a newer standard, DVB-T2, which was recently finalized. On the other hand, DVB-H is a specification for the transmission of digital TV to handheld user terminals such as smart phones delivering IP-encapsulated data. The combination of satellite and terrestrial DVB technologies is DVB-SH which delivers wide coverage to mobile terminals and promises upgraded services to mobile and vehicle users via a satellite link. The objective of our research article is to present a survey on terrestrial, mobile and hybrid DVB multimedia networks. Emphasis will be given on quality of radio and service related aspects. A focus on performance evaluation methodology based mainly on measurement campaign will be proposed with a detailed presentation of experimental equipment for drive-test field measurements. Guidelines of measurements and analysis processes will be described. A public DVB network in the area of Athens will be our case study.

Market Driven Dynamic Spectrum Allocation over Space and Time among Radio-Access Networks: DVB-T and B3G CDMA with Heterogeneous Terminals

The radio frequency spectrum is a naturally limited resource of extraordinary value, as the key to the provision of important communication and information services. Traditionally, spectrum has been allocated first to specific access technologies, and then sub-allocated to specific access networks, on very long term basis (up to decades). The traditional scheme can be very inefficient when demand patterns ("loads") exhibit high temporal and spatial variations. Dynamic spectrum allocation (DSA) improves radio spectrum efficiency by adjusting the allocation as demand changes in time and/or space. In previous work, we introduced a DSA scheme in which a spectrum manager periodically auctions short-term spectrum licenses. The scheme can be supported by a realistic "pooling" business model, and can work with many radio-access technologies. But our previous analysis only considers a code-division multiple access (CDMA) technology; and DSA provides the greatest benefits with the participation of networks having complementary "busy hours," such as video entertainment services and cellular telephony. Here, a digital video broadcast (DVB) terrestrial network joins the scheme. A typical DVB terrestrial cell is (much) larger than a UMTS cell. This brings to the forefront inter-cell interference, and inter-related auctions in different cells. To capture the essence of these issues we focus first on a situation where one DVB terrestrial cell overlays two adjacent CDMA cells. Subsequently we discuss extensions to richer scenarios. The contributions of the present work over our previous publications include to : (i) address the impact of inter-cell interference among several CDMA cells, (ii) introduce the DVB access technology into the DSA scheme, (iii) modify the auction scheme to consider that a DVB cell overlays several CDMA cells, (iv) characterise analytically the marketing and bidding behaviour of the DVB network.

Resource management of IP-enabled DVB-T networks in the context of wireless B3G systems

The wireless beyond 3G systems or the so called Composite Radio Environments (CRE) (or even 4G systems), consist of multiple type radio access technologies, collaborating with each other, providing both diverse access alternatives and QoS improvement, especially as far as concerns protection against traffic congestion and loss of radio coverage situations. The merits deriving from beyond 3G systems interest not only network and service providers but also the mobile users. Additionally, the need of broad-band wireless access is directly associated with the intense demand for IP multimedia services (e.g. video streaming or high speed web browsing), mainly inside hot-spot areas. Taking into consideration the above described tendency in the area of wireless network systems, the IP-enabled DVB-T (the terrestrial specification of the Digital Video Broadcasting family) systems appear as an attractive alternative network access in the CRE context. Along this direction, this paper presents the most important aspects of a CRE network management system (NMS), focusing on the component responsible for the DVB-T resource management (RM). Finally, we implement and investigate through simulation a greedy algorithm suitable for DVB-T networks that performs fast resource management and configuration. We also provide some indicative results which prove that the algorithm demonstrates a close to optimal performance at the RM functionality.