Marnix Claudius Vlot

Key technologies for next-generation terrestrial digital television standard DVB-T2

A new platform for HDTV transmissions, in the form of a new-generation terrestrial digital video broadcasting standard (DVB-T2), has been developed by the DVB Project and will be published by the European Telecommunications Standards Institute. A number of technical innovations have been included in DVB-T2 to boost throughput and ruggedness, enhance single-frequency network coverage, and ease both transmitter and receiver implementation. This article starts from the motivations that led the DVB project to create the new standard and then surveys the key technologies behind DVB-T2, including the LDPC/BCH forward error correction scheme, transmission scheduling, orthogonal frequency-division multiplexing with huge block size, multiple-antenna transmissions, and synchronization techniques. A comparison with the current DVB-T standard is also provided, showing that DVB-T2 is able to increase the payload throughput and allows HDTV transmission with current network planning.

Multi-media terminal architecture

Abstract This paper presents the basic hardware and software architecture of a class of multi-media terminals that are connected to networks which deliver entertainment and home shopping services to consumers. Some important attributes of the multi-media terminal are: simple user input devices (e.g. infrared remote control), real-time interactivity, adherence to international standards for information representation and communication, and support for downloaded applications from service providers. The terminal discussed in this paper is representative of the current offering of the Digital Video Communication Systems (DVS) business unit of Philips. These terminals are the result of close cooperation between research and product divisions of Philips world-wide in the race to compete in the rapidly growing multi-media and communications markets. The current architecture of the terminal reflects the urgency to get to market with a viable solution; therefore the paper gives some indication of future trends for the hardware and software architecture for this class of multi-media terminals.

The POOMA architecture

This article contains an overview of the POOMA hardware architecture and its prototype implementation, as developed within the machine subproject of the PRISMA (PaRallel Inference and Storage MAchine) project. The prime objective of the POOMA (Parallel Object Oriented MAchine) architecture is to support high performance database applications. These applications are both data-intensive and processing-intensive. Optimal support is achieved by using a large main memory in order to make access to large amounts of data very fast, and by using parallelism in order to obtain the required processing capacity. The POOMA architecture is based on a network of computing ‘nodes’; each node consisting of a Data Processor, a memory and a Communication Processor. This approach leads to a scalable multiprocessor with distributed memory, the network being the most novel part of the architecture. Secondary storage in the form of disks is intended only for archiving purposes. A 100-node prototype has been implemented and is currently in use for software implementation and experiments. The implementation of the system, the nodes, the network, Communication Processor and the software environment for using the machine are described in some detail. Some evaluation results and comparisons with other systems are presented, confirming the potential of the hardware architecture as such.