DOTE

Chain And Rate

Saturday, December 29, 2012

DVB Network Architecture

A DVB-H network is a highly centralized, centrally managed infrastructure. Programs, applications and services are created and managed by the service providers. A DVB-H network enables the transmission of several types of multimedia services for small devices, so there are two needs: to save power on the receiver side and to have a robust signal to provide service to receivers such as mobile cellular telephony. DVB-H uses different handheld reception modes, which are based on where the device is placed: indoor handheld reception (at very low or no speed) and outdoor handheld reception (from high to very high speed).

DVB-T Broadcasting Spectrum
In this type of network, DVB-H uses the same broadcasting spectrum as DVB-T.24 Both have the same physical layer, so they have full-spectrum compatibility, and any DVB-T frequency allotment or assignment can be used also for DVB-H. DVB-H can be introduced sharing an existing DVB-T multiplex offering DVB-H and DVB-T services. One 8 MHz channel can deliver 30–50 video-streaming services to the small screen terminals.
DVB shared network
Shared Network Of DVB(s)
It is 10 times more than SDTV or 20 times more than HDTV.25 An example of a shared network could look like the one shown above. DVB-T transmitters are serving both DVB-H and DVB-T terminals. The current sharing is done  at the multiplex level. The existing DVB-T network has to be designed for portable indoor reception to provide high enough field strength for the handheld terminals inside the wanted service area. DVB-H offers full flexibility to select the wanted portion of the multiplex to DVB-H services. The key DVB-H component in the network is the IP encapsulator, where the MPE of IP data, time slicing, and MPE-FEC are implemented.

mobile and broadcast collaboration
Collaboration Of Mobile And Broadcast Operators
One approach to constructing a total end-to-end DVB-H system making use of a mobile telecommunication network for subscription billing is shown above. Broadcast services can be delivered by DVB-H without the need for an interaction channel, or in the configuration shown, an interaction channel can easily be provided using a cellular network such as the GSM network. Methods for providing services payment can be built upon a proprietary encryption and payment solution or in conjunction with the telecoms network’s inherent service statistics collection and billing functions. While the DVB-T network is intended primarily for rooftop antenna reception, a DVB-H network will be designed for portable reception available even inside buildings. Hence, it will need a much higher signal power density. To reach the higher power density needed for mobile coverage levels, several network architectures can be used depending on available frequencies, allowed maximum transmitter powers, and antenna heights.