Techniques of on – air broadcasting network building

Introduction of digital broadcasting on the territory of the Republic of Kazakhstan
Transition to digital broadcasting is certainly a priority direction of social and economic development in the Message of the President of the Republic of Kazakhstan to people of Kazakhstan.

The decree of the President of the Republic of Kazakhstan was prepared by the Ministry of Communications and Information in association with state bodies of mass-media and communication. The Introduction of digital broadcasting on the territory of the Republic of Kazakhstan is again entrusted to the established Ministry.

Participants in the project, with support of the Ministry of Communications and Information of RК are:

  • Kazteleradio JSC
  • RGE TSKAT
  • Kazakhtelecom JSC

Performance of tasks on digital broadcasting introduction is planned to be carried out in several stages:

  • · Start of digital satellite broadcasting in Almaty (till December, 1st, 2010);
  • · Carrying out of test works, for definition of the uniform standard of digital radio broadcasting DVB (up to end 2010)
  • · Development of the frequency-territorial plan (till December, 15th 2010)
  • · Pilot project of digital radio air-broadcasting on the territory of Karaganda region (2011)
  • · Introduction of digital broadcasting in frontier zones (from 2011)
  • · Introduction of digital broadcasting on the whole territory of the Republic of Kazakhstan (2011-2015)

For carrying out test works, the experimental zone chosen is the territory of Karaganda region with a television broadcasting center in Karaganda. In the given work is used a digital television transmitter NV8304E, DVB-T/T2 made by «Rohde&Schwarz» Company. The choice of the given district is based on the existence of a relief and of industrial noises.

The purpose of carrying out the given actions is the selection of a uniform digital standard of radio air-broadcasting on the territory of the Republic of Kazakhstan, as well experimental confirmation of equipment standards advantage DVB-T2 and DVB-T use by field tests.

The measurements performed in a given place, have objectively shown technical opportunities of each standards of radio digital broadcasting DVB-T and DVB-T2 as in city district, and the areas located in various conditions of an environment.

Broadcasting standard DVB-T

Broadcasting standard DVB-T2

Broadcasting parameters

Broadcasting parameters

64QAM, 8к, FEC =3/4, D=1/32 at traffic flow speed 27 Mbit/sec

64QAM, 8к, FEC =3/4, D=1/32 at traffic flow speed 32,2 Mbit/sec

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256QAM, 32k, FEC 2/3 D=1/128 at traffic flow speed 40,2 Mbit/sec.

Cover zones DVB-T (64QAM; 8k; FEC =3/4; D=1/32)

Distances in each direction are non-uniform. It is connected with relief singularity and presence of industrial radio noises. So, in the northern direction the zone of the reliable reception is at a distance of 21,7 km from a RTF. In turn, it is connected with local relief (hills).

In the east direction we receive at a distance of 24,6 km.

In the southwest and southern direction the zone of reliable reception is much more. It is connected with direct visibility in reliefs of the specified directions.

In each of the specified directions have been removed from 4 up to 7 indications in control points what has allowed to more precisely define a zone of reliable reception.

Coverage zones DVB-T2 (64QAM; 8к; FEC =3/4; D=1/32)

With broadcasting in standard DVB-T2 in modulation 64QAM, the zone of reliable reception considerably increases, as well as the quantity of broadcast transfers due to increase in speed of stream. In all directions is felt an appreciable increase in a zone of reception from 25 up to 40 %. Moreover, in southern directions reception of a signal was carried out on 52 km. But in this case, considering visual presence of a picture, parameters of signals were below threshold values for the given standard of a digital broadcasting.

As a result of the carried out comparative testing the following advantages of standard DVB-T2 in comparison with DVB-T have been confirmed:

  • Increase of TV-programs amount in a digital package with 7 SD programs up to 14 SD and as consequence – an opportunity of radio frequencies liberation for secondary use.
  • Increase in channel filling from 27Mbit/sec up to 32,4 Mbit/sec for mode DVB-T2 with 64QAM, quantity of subcarriers 8, FEC–3/4, a protective interval 1/32, and increase in a zone of confident reception at 25 % at other equal parameters (in some points the maximal distance from Karaganda RTF has been of up to 51 km, that is 41 % more in comparison with DVB-T)
  • Use of modulation 256QAM, 32k, FEC 2/3 D=1/128 and speeds of a transport stream 40,2 Mbit/sec DVB-T2, in view of use of the equipment presented for tests, has resulted in practically full concurrence of a coverage zone for a mode 64QAM DVB-T, but about an increase in the quantity of broadcast TV of programs SD from 8 up to 14.

In December 2010 have been executed similar tests in Karaganda on the basis of the equipment of the Harris company. Results coincide with results of testing with the equipment of the company “Rohde&Schwarz”.