The ISIS Project aims to demonstrate the technical and economical feasibility of interactive services via satellite in the framework of the future European multimedia scenario.
Specific emphasis is placed on the critical issues associated with a dual-band satellite link concept, namely Ku band (12-14 Ghz) on the forward path and Ka band (20-30 Ghz) on the return interactive path. The objective of the project will not only be to define the suitability of such a technology choice but also to point out the applications and services which can be better exploited on the defined system architecture.
Further goals of the ISIS Project are:
to stimulate the research background required to develop future industrial multimedia services and products.
to optimise the integration of satellite resources with terrestrial networks for multimedia services delivery.
to contribute to Standardisation Bodies on return channel physical layer and access scheme.
ISIS Project expectations are focused on the education of service providers and consumer technology manufacturers with regard to the effective performances realised by an ISIS platform, characterised by the peculiar capabilities of satellite telecommunication within the frame of multimedia interactive applications.
The results of the ISIS Project are expected to bring a significant breakthrough in the near future scenario of the Information Highways. In addition to the typical advantages of broadcasting satellite systems, two major issues driven by ISIS Project will be brought to the competitive market:
a) The advent of digital technologies for telecommunication satellites which is going to broaden the transporter capacity and consequently the cost competitiveness of the Mbit delivered on ground.
b)The exploitation of Ka-band which will make available to service providers the required frequency bandwidth without congestion problems.
Main contributions to the programme objectives:
An integrated dual band (Ku, Ka), satellite based, interactive platform for multimedia services.
Contribution to the programme
ISIS Project has produced architectural designs and service solutions and in the forerunner of real commercial systems, foreseen to be operative throughout Europe at the beginning of 2000.
The ISIS Project is being developed in four phases:
Service definition: In this phase candidate applications have been analysed, targeting two main categories of users, namely "residential" and "business", from which the user profile has been derived. This task has been completed, translating user profile and hence user requirements in communication specifications.
System design: The typology of the overall system architecture for the operative system has been assessed and designed. A specific effort has been placed on the satellite access scheme for the return channel operating in Ka band, aimed at identifying a powerful access protocol and a physical layer which are close to the ones of a pre-commercial product. In parallel the existing test bed, on which the experimental campaign will be run, has been traded off and evaluated for its adequacy in relation to the present Project objectives.
Assessment of the system economical viability: During this task the different component of the system architecture will be analysed in terms of cost competitiveness in the context of a wide expansion of services provided through an ISIS-like operative system.
Test campaign: In this phase a number of selected applications will be run on the existing test-bed. They may be limited in performance by the existing platform (not designed specifically for this purposes and not fully representative of the operative system) but will however provide validation of the design approach.
Summary of Trial
Operative trials will be starting in December 1997 for a time period of about three months. The trial campaign will mainly focus on application capability experimentation rather than "technology proof."
The essential components of the test bed will be:
Satellite providing Ku-band capacity: EUTELSAT/Hot Bird series (located at about 13° E)
Satellite providing Ka-band capacity: ITALSAT FII (located at 13.2°).
One user-terminal (Direct to home terminal including set top box); the dish is expected to be 0.8 m, equipped with a 300/600 mW solid state power amplifier, capable to support return channel bursty packets at 64 kbps.
Broadcasting Centre (BC) which will up-link to the two satellites and receive and manage the return traffic. The Ku-band up-link will be a MPEG2 DVB-S containing the required information embedded on the MPEG2-TS: it also conveys the in-band signalling stream generated in order to provide data on system synchronisation, reserved upstream slots, collision information, location of requested information on MPEG2-TS.
The BC will be located at RAI Centre in Turin.
Video Server (co-located at the Broadcasting Centre): the core protocol for delivery of services will be the TCP\IP stack, with the exception of high-bit rate video , that will be based on the MPEG2 video encoded file.
Applications which will be run on the demonstrator are planned to be:
Novel INTERNET services
Distribution of electronic newspapers
Drivers of the ISIS Project are considered to be:
Optimisation of satellite access on the return link in Ka-band (in terms of protocols ,modulation, coding, link budget trade-offs)
Cost effectiveness of the user DTH terminal (RF sub-system and set top box): it is expected that, if mass production is exploited, the end user cost will be less than 1300 USD (96) within 5 years.
Integration of ISIS platform on surrounding multimedia environment
Optimisation of the video server communication layers
Funding SchemeCSC - Cost-sharing contracts