Kannan Krishnapillai

Service Platform for Converged Interactive Broadband Broadcast and Cellular Wireless

A converged broadcast and telecommunication service platform is presented that is able to create, deliver, and manage interactive, multimedia content and services for consumption on three different terminal types. The motivations of service providers for designing converged interactive multimedia services, which are crafted for their individual requirements, are investigated. The overall design of the system is presented with particular emphasis placed on the operational features of each of the sub-systems, the flows of media and metadata through the sub-systems and the formats and protocols required for inter-communication between them. The key features of tools required for creating converged interactive multimedia content for a range of different end-user terminal types are examined. Finally possible enhancements to this system are discussed. This study is of particular interest to those organizations currently conducting trials and commercial launches of DVB-H services because it provides them with an insight of the various additional functions required in the service provisioning platforms to provide fully interactive services to a range of different mobile terminal types

Laboratory Measurement Campaign of DVB-T Signal With Transmit Delay Diversity

The requirements for future DVB-T/H networks demand that broadcasters design and deploy networks that provide ubiquitous reception in challenging indoors and other obstructed situations. It is essential that such networks are designed cost-effectively and with minimized environmental impact. The EC funded project PLUTO has since its start in 2006 explored the use of diversity to improve coverage in these difficult situations. The purpose of this paper is to investigate the performance of Transmit Delay Diversity (DD) with two antennas to improve the reception of DVB-T/H systems operating in different realistic propagation conditions through a series of tests using a SPIRENT SR5500 dual channel emulator. The relationship between correlation coefficient between channels, receiver velocity and diversity gain is investigated. It is shown that transmit delay diversity significantly improves the quality of reception particularly in simulated fast fading mobile broadcasting applications. This paper documents research conducted by Brunel University and Broadreach Systems.

Multimedia broadcast and internet satellite system design and user trial results

The EU funded project, System for Advanced Multimedia Broadcast and IT Services (SAMBITS), has created an enhanced and synchronised, multimedia terminal for merging satellite broadcast and internet telecommunication services in a way that efficiently combines the large bandwidth of the broadcast channel and the interactivity of the internet. This paper proposes a novel broadcast and internet service concept, illustrates this concept with two service scenarios and develops a system architecture to demonstrate the range of key benefits provided by these new technologies. It then describes the interactive multimedia terminal that was used for consuming this new service concept. Finally, the results of the user trials on the terminal are presented and discussed.

Rapid prototyping and fast user trial of multimedia broadcast and cellular services

This paper presents the results of fast user trial of multimedia services that are enabled when a mobile terminal has access to converged services over digital broadcast and mobile telecommunications networks. It first describes the motivations behind developing this system and describes the service scenarios that benefit most from it. It then provides an overview of the service components of the test case scenario. Finally, it presents the results of fast user trials on end users of the services that were developed. This work was conducted as part of the EU-funded CISMUNDUS project.

A Field Measurement Campaign for a DVB-T/H System with Transmit Delay Diversity

This paper presents a field measurement campaign carried out by the IST PLUTO project to quantify the advantages that can be achieved practically if transmit delay diversity is applied to DVB-T/H systems. An extensive field trial was performed in Uxbridge (UK) to validate transmit diversity gain predictions obtained previously from theoretical modelling and laboratory measurements. DVB-T/H transmissions were performed in the 730 MHz frequency band. It is concluded that transmit delay diversity achieves significant improvement in the reception quality in difficult to reach areas without impacting the standard or increasing the complexity of receivers.

Field trials and test results of portable DVB-T systems with transmit delay diversity

This paper describes work carried out by Brunel University and Broadreach Systems (UK) to quantify the advantages that can be achieved if transmit diversity is applied to systems employing the DVB standard. The techniques investigated can be applied to standard receiver equipment without modification. An extensive and carefully planned field trial was performed during the winter of 2007/2008 in Uxbridge (UK) to validate predictions from theoretical modeling and laboratory simulations. The transmissions were performed in the 730 MHz frequency band with a DVB-T transmitter and a mean power of 18.4 dBW. Transmit delay diversity has been observed to deliver significant reception improvement in automotive and indoor- non line of sight situations.

Measurement results of transmit delay diversity for DVB-T networks

This paper describes work carried out by Brunel University and Broadreach systems (UK) to quantify the advantages that can be achieved if transmit diversity is applied to systems employing the DVB standard. The techniques investigated can be applied to standard receiver equipment without modification. An extensive and carefully planned field trial performed during the winter of 2007/2008 in Uxbridge (UK) is described. The transmissions were performed in the 730 MHz frequency band with a DVB-T transmitter and a mean power of 18.4 dBW. Transmit delay diversity has been observed to deliver significant reception improvement in automotive- non line of sight situations.

Broadcast technologies for disseminating cultural heritage

This paper introduces the System for Advanced Multimedia Broadcast and IT Services (SAMBITS). It consists of a Studio, Server and TV Terminal system for broadcasting audio/video TV content enhanced by 3D graphics, Internet pages, database indexing and sub-image streaming. It describes two scenarios program for disseminating cultural heritage. The readers are invited to imagine how this system could be used to prepare programs for disseminating archaeology. The paper describes the Studio and Server Tools and the main functionality of the TV terminal. It describes the functionality of the terminal through the description of the scenario in conjunction with illustrative screen shots.

Evaluating existing set-top boxes versus transmit diversity schemes

Transmit diversity is a technique that exploits the nature of fading due to multipaths and that potentially incurs delay and pre- and post-echoes into the received signals. There is some concern that early set-top boxes would not be compliant in this respect. Also, introduction of such techniques that would degrade reception for in-service equipments would have an important impact, which should be evaluated. This paper presents a measurement campaign to establish whether the in-service DVB-T receivers are compatible with transmit diversity schemes and also to evaluate the possible diversity loss in the line-of-sight fixed receptions.