Optimal nonlinear filtering of MPSK signals in the presence of a Doppler frequency shift
https://doi.org/10.32362/2500-316X-2022-10-1-41-49
Abstract
Objectives. Phase-shift keyed (PSK) signals are widely used in many telecommunication, communication, and cellular information transmission systems. Phase-shift keying provides a higher noise immunity than amplitude and frequency modulations do. An increase in the modulation order of such a signal leads not only to an increase in its spectral efficiency, but also to a certain decrease in the noise immunity of reception. To ensure a high noise immunity of reception of multiple phase-shift keyed (MPSK) signals, a demodulator should provide the coherence of the reference oscillation with the carrier. Ignorance of the frequency and phase of the received signal leads to significant energy losses. The purpose of this work was to synthesize and analyze algorithms for receiving MPSK signals with phase fluctuations caused by changes in the carrier frequency due to the Doppler effect against the background of white Gaussian noise.
Methods. The problem was solved using the apparatus of optimal nonlinear filtering and methods of statistical radio engineering.
Results. A demodulator was synthesized, which includes two interconnected units. One of them is a discrete symbol estimation unit, at the output of which a decision on the received symbol is issued, and the other is a phase-lock circuit. Analytical expressions were derived to estimate the characteristics of the receiver noise immunity as functions of the signalto-noise ratio and fluctuation parameters. It was shown that the synthesized quasi-coherent algorithm compensates well for the MPSK signal phase fluctuations caused by the instability of the master oscillator and the Doppler effect.
Conclusions. Comparison of the results of this work with results obtained in the case of the absence of fluctuations in the initial phase showed that, at a high relative speed of the transmitter and the receiver (satellite radio channel), the energy loss is no more than 1 dB, and at lower speeds of the objects, it is about 0.2 dB and less.
About the Authors
G. V. KulikovRussian Federation
Gennady V. Kulikov, Dr. Sci. (Eng.), Professor, Professor of the Department of Radio electronic Systems and Complexes, Institute of Radio Electronics and Informatics Systems
119454, Moscow, Vernadskogo pr., 78
T. T. Do
Russian Federation
Trung Tien Do, Postgraduate Student, Department of Radio Electronic Systems and Complexes, Institute of Radio Electronics and Informatics
119454, Moscow, Vernadskogo pr., 78
R. R. Usmanov
Russian Federation
Renat R. Usmanov, Engineer
115054, Moscow, Kosmodamianskaya nab., 52-3
References
1. Proakis J.G. Digital communications. 4th ed. McGrawHill; 2001. 1002 p.
2. Fuqin Xiong. Digital modulation techniques. Series: Artech House Telecommunications Library. 2nd ed. Artech House Print on Demand; 2006. 1039 p.
3. Akimov V.N., Belyustina L.N., Belykh V.N., et al. Sistemy fazovoi sinkhronizatsii (Phase synchronization systems). Shahgildyan V.V., Belyustina L.N. (Eds.). Moscow: Radio i svyaz’; 1982. 289 p. (in Russ.).
4. Kulikov G.V., Nguyen Van Dung. Effect of inaccuracy of the clock synchronization on the noise immunity of coherent reception of MPSK signals. In: “Actual Problems and Prospects for the Development of Radio Engineering and Infocommunication systems. RADIOINFOKOM 2019.” Proc. IV International Scientific and Practical Conference. Moscow. 2019. P. 109−113 (in Russ.).
5. Kulikov G.V., Nguyen Van Dung. Effect of inaccuracy of the carrier frequency and phase estimation on the noise immunity of coherent reception of MPSK signals. In: “Actual Problems and Prospects for the Development of Radio Engineering and Infocommunication systems. RADIOINFOKOM 2019”. Proc. IV International Scientific and Practical Conference. Moscow. 2019. P. 114−122 (in Russ.).
6. Simongauz V.I. Optimal synchronization and demodulation of a radio signal with multi-position phase manipulation. Radiotekhnika = Radio Engineering. 2017;11:87−96 (in Russ.).
7. Kulikov G.V., Nguyen V.D. Influence of synchronization errors оn the noise immunity of coherent reception of M-PSK signals. Rossiiskii tekhnologicheskii zhurnal = Russian Technological Journal. 2019;7(5):47−61 (in Russ.). https://doi.org/10.32362/2500-316X-2019-7-5-47-61
8. Miroshnikova N.E. Phase and timing synchronization error on digital receiver properties. T-Comm: Telekommunikatsii i Transport = T-Comm: Telecommunications and Transportation. 2013;9:112−114 (in Russ.).
9. Gogoleva S.A., Demidov A.Ya., Karataeva N.A., Maikov D.Yu., Voroshilin E.P. Assessing of impact of frequency detuning on the probability of bit error in the OFDMA communication systems. Doklady Tomskogo gosudarstvennogo universiteta sistem upravleniya i radioelektroniki = Proceedings of TUSUR University. 2011;2:45−48 (in Russ.).
10. Tikhonov V.I. Statisticheskaya radiotekhnika (Statistical radio engineering): 2nd ed. Moscow: Radio i svyaz’; 1982. 624 p. (in Russ.).
11. Yarlykov M.S. Primenenie markovskoi teorii nelineinoi fil’tratsii v radiotekhnike (Application of the Markov theory of nonlinear filtering in radio engineering). Moscow: Sovetskoe Radio; 1980. 258 p. (in Russ.).
12. Tikhonov V.I., Kharisov V.I., Smirnov V.A. Optimal filtration of discrete-continuous processes. Radiotekhnika i elektronika = Radio Engineering and Electronics. 1978;23(7):1441−1452 (in Russ.).
13. Yarlykov M.S., Mironov M.A. On the applicability of the Gaussian approximation in the Markov theory of optimal nonlinear filtering. Radiotekhnika i elektronika = Radio Engineering and Electronics. 1972;17(11):2285−2294 (in Russ.).
14. Tikhonov V.I., Kul’man N.K. Nelineinaya fil’tratsiya i kvazikogerentnyi priem signalov (Nonlinear filtering and quasi-coherent signal reception). Moscow: Sovetskoe Radio; 1975. 704 p. (in Russ.).
15. Yarlykov М.S. Optimal and quasi-optimal algorithms for receiving and processing BOC signals in promising global navigation satellite systems. J. Commun. Technol. El. 2021;66(1):34−55. https://doi.org/10.1134/S1064226921010101
16. Kanavin S.V., Panychev S.N., Samotsvet N.A. Method of increasing noise immunity of communication systems and information transmission based on nonlinear correlation filtering. Vestnik Voronezhskogo instituta MVD Rossii = Bulletin of Voronezh Institute of the Ministry of Internal Affairs of Russia. 2021;1:143−152 (in Russ.).
17. Gradshtein I.S., Ryzhik I.M. Tablitsy integralov, summ, ryadov i proizvedenii (Tables of integrals, sums, series and products). Moscow: Nauka; 1971. 1108 p. (in Russ.).
Supplementary files
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1. Circuit diagram of a quasi-coherent receiver of an MPSK signal in a presence of a Doppler frequency shift | |
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Type | Исследовательские инструменты | |
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Indexing metadata ▾ |
- Using optimal nonlinear filtering methods, a quasi-coherent algorithm for receiving signals with multiple phase-shift keying was synthesized, compensating for phase fluctuations and carrier frequency changes caused by the instability of the master oscillator and the Doppler effect.
- The noise immunity assessment showed that the algorithm makes it possible to compensate for the influence of the Doppler effect, both at low and high speeds of the receiver and transmitter relative to each other.
Review
For citations:
Kulikov G.V., Do T.T., Usmanov R.R. Optimal nonlinear filtering of MPSK signals in the presence of a Doppler frequency shift. Russian Technological Journal. 2022;10(1):41-49. https://doi.org/10.32362/2500-316X-2022-10-1-41-49