THE RESEARCH OF TRANSMISSION OF DVB-C TELEVISION SIGNALS BASED ON THE PROTOTYPE OF TRANSCEIVER OPERATING IN THE LOWER PART OF TERAHERTZ BAND
Background. Currently digital microwave radio relay links operating in centimeter bands and in the lower part of millimeter bands (3.4 - 40.5 GHz) are widely used in the leading countries to construct their telecommunication infrastructure. Taking into account the lack of spectrum in these frequency bands and growing necessity to transmit high-rate applications with the help of brand-new radio relay equipment of the world leading manufacturers of such equipment, tendency to operate in higher parts of millimeter bands is becoming more real and practicable. At the same time, the terahertz band (100-3000 GHz) which is not used at the present time (because of complexity of construction of radio relay equipment that could operate in this band) is
also very perspective for introduction of the future radio relay equipment (for the reason of high information capacity of 100-3000 GHz band). The Research Telecommunication Institute of the National Technical University of Ukraine and the Institute of Electronics and Communications of the Ukrainian Academy of Science developed the prototype of the transceiver for operation in the lower part of the terahertz band (130-132 GHz band). For this reason there was a necessity to conduct research concerning operation of the prototype in 130-132 GHz band (that is to test quality of operation of separate blocks of transceiver by changing parameters of transmitting signals passing through it).
Objective. The purpose of the research is the parameters variation of multichannel digital broadcasting TV signals based on DVB-C standard when TV signal is transmitted through the 130 GHz transceiver prototype. DVB-C standard has been chosen for this research to have opportunity to analyze signals with different modulation schemes (from QAM-64 to QAM-256), which allowed investigating the influence of certain prototype node parameters on the signal parameters that were transmitted through it
Methods. To conduct the research the experimental installation has been constructed with several parts in it (transceiver, subsystem for generation of DVB-C television signals, subsystem for measurement of DVB-C television signal parameters). The research has been conducted in three stages using a step-by-step approach with application of one-channel, two-channel and
three-channel signals of DVB-C standard.
Results. Results of the research showed that the use of the transceiver (that has common heterodyne for transmitting and receiving parts) in the lower part of terahertz band (130 GHz) permits to transmit three TV broadcasting channels of DVB-C standard in 24 MHz bandwidth with transmission rate of 125 Mbit/s with high subjective quality of all TV programs.
Conclusions. The results of the research demonstrated high quality of digital TV signals transmission by means of transceiver constructed for application in terahertz band (130-132 GHz). The reason for such conclusion is that harmonic distortions have not been observed and phase noise of heterodyne has not led to significant channel symbols distortion on signal constellation. The next step in future research will include the research of the quality of DVB-C signal transmission for cases when terahertz radio link is used and specific heterodynes are applied in transmitting and receiving parts of the transceiver prototype. In the future the transceiver can be used for construction of digital microwave radio relay links in terahertz band for transmission and reception of digital TV signals with high rate both for broadcasting and other applications such as Internet.
Vishnevsky V., Shahnovich I., Frolov S. Millimeter band radio relay links: A new horizons // Electronika NTB – 2011. – №1. –P.90-97 [In Russian]
Kravchuk S.O., Narytnik T.M. Terahertz band telecommunication systems. Monograph. – Zhytomir: «Evenok» publishing house, 2014. – 394 p. [in Ukrainian]
Widest band amplifier ever at 235 GHz – open door to ultrafast broadband [Electronic resource]. Available at: www.chalmers.se/en/news/Pages/widest-band-amplifierever-at-235-GHz.aspx
Ilchenko M. Yu., Narytnik T. M., Radzikhovsky V.M., Kuzmin S. E., Lutchak O. V. Transmitter and receiver parts of radio relay systems operating in the terahertz band // Digital technologies. – 2015., № 17. – P.17-29 [in Ukrainian].
Ilchenko M. Yu., Narytnik T. M., Radzikhovsky V.M. Design of the transmitter and receiver parts of the terahertz band for radio relay systems//Electosvyaz. – 2016., №2. – P.42-49 [In Russian].
Ilchenko M.Ye. Transceiver for 130-134 GHZ band and digital radio relay system/M.Ye. Ilchenko, T.N. Narytnik, S.Ye. Kuzmin // Telecommunications and Radio Engineering. – 2013. – vol. 72, №17. – Р.1623–1638.
Ilchenko M. Ye., Narytnik T.M., Radzikhovsky V. M. Terahertz band radio relay system functional elements simulation //Problems of telecommunications. – 2013. – №2(11). – P.95-113 [in Russian]
Ilchenko M. Ye., Kuzmin S.E., Narytnik T. N. Transceiver for digital radio relay system in terahertz frequency band//Proceedings of 23th International Conference “Microwave Engineering and Telecommunication Technology”, Sevastopol, Ukraine, September 8-13,
– Sevastopol: Veber, 2013. – P. 318–319 [in Russian].
Narytnik T.N., Ilchenko M. Ye., Radzikhovsky V. N. Radio channel research for terahertz band telecommunication systems of next-generation //Proceedings of 10th International Conference “Problems in telecommunications”, Kyiv, Ukraine, April 22-25, 2014 – Kyiv: NTUU
KPI, 2014 – P.137 – 140. [in Ukrainian].
Narytnik Т.N. Possibilities of Using THz-Band Radio Communication Channels for Super High-Rate Backhaul //Telecommunications and Radio Engineering. – 2014. – №73 (15). – Р.1361–1371.