Design of Antennas for Handheld DVB-H ... - Lunds tekniska högskola

2 Background
This chapter provides general information about the different DVB standards and
will give the needed knowledge about the system. Basic antenna theory will also
be presented, to help the reader understand later discussions.
2.1 Digital Video Broadcasting
2.1.1 DVB
This part will give the reader an overview of the existing Digital Video
Broadcasting – Terrestrial (DVB-T) system and the future DVB-H system.
The analogue TV system used today has basically remained unchanged for
decades, with the colour TV as the only invention worth mentioning since the
1960s. The European PAL system and the US NTSC system use the resolution of
625 lines respectively 525 lines, and the display is interlaced with only 25 or 30
frames per second. Compared with today’s computer screen with resolution of
1280�1024 and at least 75 Hz frame rate. So, it is naturally that a transition to a
digital system with higher resolution implies better picture and additional features
[1].
Until 1991 digital television broadcasting to the home was thought expensive and
impractical to implement. During 1991 broadcasters and equipment manufactures
discussed unify Europe with one standard for digital TV. The result was a group
called European Launching Group (ELG) that expanded to include the major
European media interest groups, both public and private, the consumer electronics
manufacturers, common carriers and regulators. 1993 ELG renamed itself to
Digital Video Broadcasting (DVB). The work in digital television, already
underway in Europe, moved into top gear. It became clear that Digital Video
Broadcasting–Satellite (DVB-S) and Digital Video Broadcasting–Cable (DVB-C)
were delivering digital video broadcasting before DVB-T. This depends on fewer
technical problems and a simpler regulatory.
1997 the DVB-standards were adopted globally and became the benchmark for
digital television worldwide [2].
DVB is an industry-led group with more than 300 broadcasters, manufacturers,
network operators, software developers and regulatory bodies. One of the main
goals for the group is to develop open standards to prevent the digital TV to
include as many standards as the analogue system (NTSC, PAL and SECAM)
does. Since European Telecommunication Standards Institute (ETSI) adopted
DVB as a standard, it has been implemented in many countries. An EU directive
requires all country which will implement digital terrestrial TV broadcasting to
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