The operation of telecenters with overlapping zones of reliable reception on the same frequency is completely absent in ATSC and is recommended for use in the DVB-T standard. This destroys the usual idea of frequency planning, makes it unnecessary to build high antenna structures, reduces the number of transmitters by a factor of 6-7, and makes it possible to further reduce the transmitter power by 25-30%.
Resistance to multiple reflections when the main and reflected signals are equal is provided in the DVB-T standard and is completely absent in ATSC (the level of the reflected signal is less than 15 dB).
The DVB-T standard does not require the abandonment of existing analogue television programs, as it has a high level of security for analogue TV. The less secure ATSC standard, even with NTSC notch filters, led the US government to adopt a full digital transition program.
The bandwidth in the DVB-T standard is fully adaptable to any country and is fixed in ATSC (only 6 MHz).
The transmission rate in the DVB-T standard varies from 5 to 32 Mbps and is fixed in ATSC (19.3 Mbps).
The DVB-T standard supports, as well as ATSC, HDTV and Dolby AC-3.
The actual transmitter power, for example, in London is less than 10 kW and provides reliable reception of the DVB-T standard within a radius of 114 km, while in New York a transmitter with a power of 350 kW does not provide 100% reception even within a radius of 10 km.
Reception on an indoor antenna or portable TV does not cause problems in the DVB-T standard, in the ATSC standard it is impossible in most cases.
The parameters of the DVB-T standard can be well adapted to urban areas. There is a choice: by gradually increasing the number of transmitted TV programs, when there are areas of uncertainty, decide whether it is more profitable to improve the cabling in houses or limit the number of programs reached.
The DVB-T standard allows the use of conventional outdated antenna distribution equipment, without any modifications, while in ATSC it is necessary to use narrowly directed TV antennas with the ability to adjust (using a motor), which does not guarantee reliable reception.
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July 27, 2024 03:44:23 +0300 GMT
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