Digital television
Basic info on digital tv
Why the switch-over from analogue to digital broadcasting of television programmes in the Republic of Croatia?Digital broadcasting system at certain transmitting location uses one television channel for broadcasting multiplexes consisting of numerous television programmes and contents. Digital system of television signal broadcasting thus has many advantages such as: better use of radio frequency spectrum, better sound and image quality, possibility of implementation of additional contents (digital teletext, EPG) and High Definition Television (HDTV) and the possibility of using increased aspect ratio (16:9).
Radio frequency spectrum is a naturally limited public resource. Our goal is to manage the resource with maximum efficiency. The part of radio frequency spectrum intended for television is divided into channels. Each channel is defined by its central frequency and channel width. The channel width in the UHF television area is 8 MHz. With analogue broadcasting, one television programme occupies the entire width of a radio frequency channel. With digital broadcasting, a multiplex of signals is broadcast, containing several television programmes (4 to 5 for standard quality television (SDTV) using MPEG-2 standard) and additional contents. Digital broadcasting system uses coding procedures which enable placing a larger number of television programmes in the same channel width as in analogue broadcasting, resulting in higher utilization of radio frequency spectrum.
Over the years the need for television channels has been constantly growing, resulting in large congestion of radio frequency spectrum intended for broadcasting, so the introduction of new television programmes in analogue broadcasting technology became virtually impossible. Over the years of developing digital technology, the systems of image broadcasting and compressing have been improved, resulting in the possibility of broadcasting several television programmes in a single radio frequency channel.
The appearance of digital broadcasting resulted in the need for new allocation of television channels between countries. In 2006 an international conference was held in Geneva, with the participation of countries from the ITU region 1 (Europe, Africa, a part of Asia). The new broadcasting plan (allocation of television channels) to be used for digital broadcasting was agreed upon. It was also agreed, that the analogue broadcasting of television signal shall be switched off by 2015, i.e. by 2028 for Africa.
The EU countries wish to utilize the advantages of digital broadcasting of television signal as soon as possible. They wish to create and use digital dividend for new systems and additional services. In accordance, the recommendation of the European Commission on switch-over to complete digital broadcasting of television signals and analogue switch off by the year 2012 was adopted.
In accordance with the abovementioned, the Government of the Republic of Croatia adopted the Analogue to Digital Broadcasting Switch-over Strategy at its session on 31 July 2007. The main strategic goal is a complete switchover from analogue to digital broadcasting of television programmes in the Republic of Croatia by 31 December 2010.
DVB-T signal coverage in the Republic of Croatia
During the transition period, the analogue television signal coverage of the existing broadcasters shall be substituted with the digital television signal coverage, broadcasting of television programmes in analogue technology shall be gradually switched off, providing conditions for the use of digital dividend. The switch-over from analogue to digital terrestrial broadcasting of television signal was performed gradually, using a regional model.