Improving Frequency Efficiency of Signals with Absolute Phase Shift Keying by 180^о

Communication with mobile objects in railway transport is carried out only by radio, therefore, it is of interest to maximize frequency efficiency and noise immunity of radio communication. This can be achieved using a double absolute phase-shift keying (DPSK) at 180о, but in practice it is still not used due to reverse operation of both coherent detectors of its signals.

The objective of this article is to develop a coherent detector without reverse operation, which allows to use it in practice without reducing its noise immunity. A filter-phase method of forming single-sideband with phase shift keying at 180о (SSB PSK) is proposed, which is equivalent to DPSK in frequency efficiency.

The proposed coherent detector of DPSK signals includes a reference waveform shaper (RWS) shaping the waveform from the input signal, two coherent detectors and introduced post-detector units that eliminate reverse operation of these coherent detectors. Singlelane PSK is formed using clipped speech signal and its quadrature.

1. Petrovich, N. T. Transmission of discrete information through channels with phase-shift keying [Peredacha diskretnoi informatsii v kanalakh s fazovoi manipulyatsiei]. Moscow, Svyaz publ., 1965, 423 p.

2. Volkov, A. A., Kuzyukov, V. A., Zhuravlev, O. E. Method of restoring the envelope of a clipped speech signal [Sposob vosstanovleniya ogibayushchei u klippirovannogo rechevogo signala]. Proektirovanie i tekhnologiya elektronnykh sredstv, 2013, Iss. 4, pp. 51–54. [Electronic resource]: https://www.elibrary.ru/item.asp?id=22025462. Last accessed 05.03.2020.

3. Rappoport, Th. S. Wireless Communications (Principles and Practice). New York, IEEE Press, 1996, 641 p.

4. Prokis, J. Digital communication. Trans. from English. Ed. by D. D. Klovsky. Moscow, Radio i svyaz publ., 2000, 797 p.

5. Zyuko, A. G., Korobov, Yu. F. The theory of signal transmission [Teoriya peredachi signalov]. Moscow, Radio i svyaz publ., 1972, 360 p.

6. Volkov, A. A. Radio transmitting devices [Radioperedayushchie ustroistva]. Moscow, Marshrut publ., 2002, 352 p.

7. Verzunov, M. V. Single-band modulation in radio communications [Odnopolosnaya modulyatsiya v radiosvyazi]. Moscow, Voenizdat publ., 1972, 295 p.

8. Sklyar, B. Digital communication. Theoretical foundations and practical application [Tsifrovaya svyaz. Teoreticheskie osnovy i prakticheskoe primenenie]. Moscow, Williams publ., 2007, 1098 p.

9. Russian utility model patent No. 163281 Signal detector with absolute PSK at 180˚ [Patent RF na PM No. 163281 Detektor signalov s absolyutnoi FMn na 180˚]. A. A. Volkov, M. S. Morozov. Priority dated 18.04.2016. Publ. 10.07.2016 in BI No. 19 for 2016 [Electronic resourc e ] : h t tps: //yandex.ru/pat e n t s/doc/RU163281U1_20160710. Last accessed 05.03.2020.

10. Volkov, A. A., Morozov, M. S. A method for implementing an absolute PSK at 180˚ [Sposob realizatsii absolyutnoi FMn na 180˚]. Elektrosvyaz, 2017, Iss. 2, pp. 72–74. [Electronic resource]: https://www.elibrary.ru/item.asp?id=28370759. Last accessed 05.03.2020.

11. Russian invention patent. Coherent signal detector with two-fold absolute phase-shift keying at 180˚ [Patent RF na izobretenie. Kogerentniy detector signalov s dvukratnoi absolyutnoi fazovoi manipulyatsiei na 180˚]. A. A. Volkov, M. S. Morozov. Priority dated 26.12.2018. Publ. 13.02.2020 Bul. No. 5. [Electronic resource]: https://patents.s3.yandex.net/RU2714222C1_20200213.pdf. Last accessed 05.03.2020.

12. Petrovich, N. T., Kozlenko, N. I. Transfer of clipped speech signals using phase telegraphy [Peredacha klippirovannykh rechevykh signalov s pomoschyu fazovoi telegrafii]. Radiotekhnika, 1964, Iss. 11, pp. 21–24.

13. Shevlyugin, M. V., Dang, V. P. Harmonic Interference of Traction Current in Metro Power Supply System. World of Transport and Transportation, 2015, Vol. 13, Iss. 6, pp. 88–101. [Electronic resource]: https://mirtr.elpub.ru/jour/article/view/553/882. Last accessed 05.03.2020.

14. Volkov, A. A., Volkova, I. A. Coherent detector of radio signals with phase shift keying at 180 ° Patent for invention RU2439830 C1, 10.01.2012, Application No. 2010115998/08 dated 23.04.2010 [Kogerentniy detector radiosignalov s fazovoi manipulyatsiei na 180° Patent na izobretenie RU2439830 C1, 10.01.2012. Zayavka № 2010115998/08 ot 23.04.2010]. [Electronic resource]: https://yandex.ru/patents/doc/RU2439830C1_20120110. Last accessed 05.03.2020.

15. Academy of Sciences of USSR No. 1522376. Device for recovering the carrier frequency from a single-band baseband signal [Ustroistvo vosstanovleniya nesuschei chastity iz odnopolosnogo moduliruyushchego signala]. A. A. Volkov. Priority dated 11.08.87, Publ. 13.11.89, in BI No. 42. [Electronic resource]: https://yandex.ru/patents/doc/SU1522376A1_19891115. Last accessed 05.03.2020.

16. Zyuko, A. G., Klovsky, D. D., Korzhik, V. I., Nazarov, M. V. Theory of electrical communication [Teoriya elektricheskoi svyazi]. Moscow, Radio i svyaz, 1988, 433 p.

17. Russian utility model patent No. 135464. Singleband clipped signal generator with PSK at 180˚ [Formirovatel’ odnopolosnogo klippirovannogo signala s FMn na 180˚]. A. A. Volkov, V. A. Kuzyukov, K. G. Khramov. Priority dated 24.05. 2013 Publ. 10.12.2013 in BI No. 34]. [Electronic resource]: https://yandex.ru/patents/doc/RU135464U1_20131210. Last accessed 05.03.2020.

18. Volkov, A. A., Kuzukov, V. A. Improving of clipped speech signals. World of Transport and Transportation, 2013, Vol. 11, Iss. 5, pp. 38–43. [Electronic resource]: https://mirtr.elpub.ru/jour/article/view/446/703. Last accessed 05.03.2020.

19. USSR author’s certificate No. 100138. Reception of phase telegraphy without a synchronous heterodyne [Priem fazovoi telegrafii bez sinkhronnogo geterodina]. L. I. Yaroslavsky [et al]. Priority dated 1951.