Market potential for multi-channel interactive digital TV and broadband services is identified and rising. However, availability of low-cost, easily-installed "last mile" end-user access is a serious barrier to exploitation. Low-power cellular wireless, coupled with in-band interactive return links, offers a potentially attractive solution.
CABSINET intends to clarify the technical and commercial uncertainties surrounding this area. The main objectives are:
to design, build and demonstrate a working interactive cellular TV architecture at 40 GHz, capable of the delivering both broadcast and ATM-derived multimedia services
to compare the performance of this system with identified market requirements
to derive an exploitation plan for such services in the short/medium term
to determine the potential for migration (e.g. to near-symmetric interactive broadband services)
The project will liaise with the CRABS project in technical and commercial assessments.
The output of the project will include:
A proven and flexible Architecture for supporting interactive cellular TV and ATM-derived services, as well as possible future extended broadband services
Extension of know-how in key fields such as protocols, MAC techniques, frequency / cell management, coding & modulation
New authoritative inputs to emerging DVB/DAVIC and telecommunications standards
Reliable planning/simulation Tools so that roll-out of services can proceed smoothly and efficiently
The project aims to have identifiable impact and benefit for both industry and public:
stimulation of new multimedia services, creating benefit for all parties involved in the value-chain
delivery of new services (e.g. entertainment, healthcare, education) to users either currently unable to receive fibre in the home, or for whom such provision is uneconomical
acceleration of the production of affordable equipment, and facilitation of competitive supply of such equipment
positioning of European industry favourably for leadership in an important new market arena
Main contributions to the programme objectives:
Development and demonstration of two layer LMDS system with interactivity operated in the 40.5-42.5 Ghz and 5.2 Ghz frequency bands based on terrestrial technology.
Contribution to the programme
Development of inexpensive broadband access for Interactive Multimedia Services.
Technically, the work will break new ground on several fronts:
a novel cellular Two-Layer Network (TLN), with Macrocells serving a locality and Microcells serving specific terminal clusters
an innovative 40 GHz in-band wireless return link (using both TDMA and CDMA spread spectrum) will maximise interference immunity and be able to migrate from asymmetric to near-symmetric broadband interactivity
flexible terminal support, including 'fixed' units and 'nomadic' wireless units with limited mobility, and service delivery to terminals inside buildings
Development will focus on the optimisation of modulation, coding and DSP methods to maximise performance in difficult propagation conditions. DVB and DAVIC standards will be followed wherever possible.
Summary of Trial
The trial will involve Macrocell and Microcell deployment in Berlin, connected via a trans-European ATM link to the JASMIN platform in Rennes. Real interactive cellular TV applications, together with ATM-derived services, will be run to determine performance and user acceptability.
Both line-of-sight connections to 'fixed' terminals, and in-building delivery to 'nomadic' terminals, will be shown.
User surveys will be conducted with 2 types of demonstration:
Interactive TV. At least 4 programmes will be presented with 4/3 and 16/9 aspect ratios. Surround sound, a TV Guide and Pay TV will be demonstrated.
Interactive multimedia services. Video on Demand, News on Demand and other ATM-derived services will be demonstrated.
Formal viewer reaction surveys will be conducted with samples of individuals invited to the viewing rooms.
Key issues include:
Standards recommendations and spectrum allocations are incomplete (particularly covering the return link)
System design involves a sensitive optimisation of bandwidth needs, propagation issues and system performance parameters
A suitable architecture must permit reliable reception and interactivity both to and within user locations where cabling may be disruptive and high in cost
Standardised access should be provided to both fixed and nomadic terminal equipment from a variety of source possibilities - e.g. satellite, cable, B-ISDN, Internet
An adequate numbers of users per cell must be supported
Funding SchemeCSC - Cost-sharing contracts
BT7 1NN Belfast