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CALCULATION METHOD OF SERVICE ZONE DIGITAL DRM TRANSMITTER
Virgilio Mateus Joào dos Santos, Malanzhe, Angola,
svirgilio5@gmail.com
Yuri A. Kovagin, St. Petersburg State University telecommunications them. prof. M.A. Bonch-Bruevich, St. Petersburg, Russia,
kowalgin@sut.ru
Alekseev M. Aleksandrovich, St. Petersburg State University telecommunications them. prof. M.A. Bonch-Bruevich, St. Petersburg, Russia, miho23@bk.ru
Abstract
The object of study is the methodology and software developed by the authors in the Matlab environment for calculating the radius of coverage of a digital DRM transmitter at frequencies below 30 MHz (applied to the middle frequency range) based on the primary data available in the ITU-R recommendations. The basis of the performed calculations are the digitized data of the 1 kW transmitter field strength, calculated using the GRAWE program for different values of frequencies, soil conductivity and dielectric constant of the medium, available in the recommendation ITU-R P.368-9 in the form of corresponding curves. The method of calculation itself includes the following steps: calculations of the median and maximum values of the level of atmospheric noise, exceeded during 2% of the transmission time, the levels of industrial noise; total noise level exceeded during the 2% transmission time; minimum transmitter field strength at the boundary of the service area, at which the requirements necessary for comfortable listening are still being fulfilled; assessment of the correction factor to take into account long-term and short-term changes in the transmitter field strength, due to the presence of seasonal and climatic changes, solar activity, terrain, time of day; the influence of the spatial wave appearing in the dark, local changes in field strength in the service area. The final part presents the results of calculations obtained using the developed computer program, as well as a comparison of experimental and theoretical data. The data entered into the program is still oriented for use in the Republic of Angola, but is also useful for other territories.
Keywords: calculation of the service area, digital broadcasting in the DRM format.
References
1. RCC Commission for Regulation of the Radio Frequency Spectrum and Satellite Orbits. Report of the working group on broadcasting «The introduction of digital sound broadcasting in the bands below 30 MHz. Document RG PB / 06/249, January 29, 2016.
2. Recommendation ITU-R BS.1415-2 (03/2011) A digital sound broadcasting system in the broadcasting bands below 30 MHz.
3. Recommendation ITU-R BS.1615-1 (05/2011). Scheduling parameters for digital sound broadcasting at frequencies below 30 MHz.
4. Recommendation ITU-R P.368-9 (02/2007) Ground-wave propagation curves for frequencies between 10 kHz and 30 MHz.
5. Recommendation ITU-R P.832-3 (02/2012) World Atlas of Soil Conductivity. Geneva.
6. Handbook on Earth Wave Propagation, -ITU-R, Radiocommunication Bureau. 2014 Edition.
7. Recommendation ITU-R P.372-13 (09/2016) Radio noise.
8. Varlamov O.V, Varlamov V.O. (2017).The distribution of maximum levels of atmospheric radio noise in the low-frequency and mid-frequency bands over the land. Science-intensive technologies in Earth space research. Vol.9. No. 5, pp. 42-51.
9. Santos V. Kovagin Yu.A. (2018). Accounting for noise at frequencies below 30 MHz when calculating the service areas of DRM transmitters. Informatization and Communication, no. 5, pp. 219-231.
10. Varlamov O.V., Varlamov V.O. (2018). Determination of the service area of the DRM digital radio broadcasting standard, taking into account the distribution of atmospheric radio noise. MTUCI. Moscow.
11. Varlamov O.V. (2017). Technology for creating a digital broadcasting network of the DRM standard for the Russian Federation: dis. … Dr. tech. Sciences: 05.12.04. M., 2017.
12. Recommendation ITU-R P.1321-5 (07/2015). Propagation factors affecting systems using digital modulation techniques at LF and MF.
13. Chernov. Yu.A. (2017). Radio wave propagation and applied issues. Moscow: Technosphere 682 p.
14. ITU-R Handbook for Earth Wave Propagation. Publishing. (2014).
Information about authors:
Virgilio Mateus Joào dos Santos, Postgraduate student – department of radio communications and broadcasting of St. Petersburg State University telecommunications them. prof. M.A. Bonch-Bruevich, Malanzhe, Angola
Yuri A. Kovagin, Doctor of technical sciences, professor, department of radio communications and broadcasting of St. Petersburg State University telecommunications them. prof. M.A. Bonch-Bruevich, St. Petersburg, Russia
Alekseev M. Aleksandrovich, Master student – department of radio communications and broadcasting of St. Petersburg State University telecommunications them. prof. M.A. Bonch-Bruevich, St. Petersburg, Russia