F.I. Ageev – Lecturer, Department of Systems and Means of Radio-Electronic Struggle for Space Purposes, Mozhaysky Military Space Academy (Saint Petersburg)
M.S. Vorona – Senior Engineer, Laboratory of Department of Systems and Means of Radio-Electronic Struggle for Space Purposes, Mozhaysky Military Space Academy (Saint Petersburg)
V.V. Zvonarev – Senior Research Scientist, Head of Laboratory, Mozhaysky Military Space Academy (Saint Petersburg)
A.S. Popov – Dr.Sc.(Eng.), Professor, Senior Research Scientist, Mozhaysky Military Space Academy (Saint Petersburg)
The analysis of conditions under which disruptions of communication with land, air, space means at small corners of the place are possible is presented in article. It is shown that possible violations of information transfer follow directly from the conditions of his work consisting in distribution of radio signals in space, emergence of a mnogoluchevost in the intake of the ground station of reception (GSR) of information as a result of repeated rereflection of signals from buildings, constructions, surfaces of various character.
During the researches it is established that at transfer of discrete messages in the conditions of dying down of a signal the communi-cation quality significantly worsens. For more exact assessment of a channel resource and the maximum weakening of influence of dying down of a signal it is necessary to create the most adequate models of the channel and a technique allowing with high precision and reliable forecasting to calculate characteristics of a radio channel. As key parameters of a radio channel at dying down in the theory of transfer of discrete messages reliability of communication and average probability of an error of reception of information symbol are applied. On the other hand in article it is shown that the important characteristic is the probability of the correct reception of the message, both in absence, and in the presence of organized hindrances. Traditional parameter of reliability of communication isn't identical to this probability. At her definition the different approach, namely, introduction of the additional characteristic of a radio channel of communication in the presence of dying down is necessary. Such characteristic in article is the probability of the bezobryvny (not broken) communication by transfer of discrete messages of the final (set) duration.
The probability of bezobryvny communication is understood as probability that on the set time interval of a communication session the level of a signal won't fall below the threshold (set) level. Use of the offered communication quality indicator in an information transfer radio channel in the conditions of dying down at the organization of communication allows: without artificial loss of capacity of a radio channel to provide with high precision maintenance of the required quality of a radio channel in the current time; to predict probability of the correct reception of messages when using of the required modes of transfer of discrete messages and ways of reception of signals; to increase noise stability of reception of information in a radio channel with dying down; to define more exact values of characteristics of a radio channel of information transfer at a design stage for different ways and the modes of reception.
In article basic contradictions are given in the accepted method of calculation of indicators of quality of a radio channel of transfer of discrete messages in the presence of casual dying down of a signal, in particular, determination of average probability of a mistake in reception of a symbol of the message. Is proved that these contradictions which are shown in ambiguity of results of calculation under identical conditions are caused by inadequacy of one-dimensional probabilistic model of dying down, namely, not accounting of dynamic characteristics of casual process of dying down.
The method of calculation of a radio channel based on new multidimensional probabilistic model of dying down and use of probability of the correct reception of the discrete message as indicator of quality of the channel is offered. Results of calculation of a radio channel are given in a concrete example. It is shown that even at worst the range of communication is 15−20% more than the Rayleigh statistics of dying down, than calculated by the accepted technique. Besides, as a result of researches the functional dependence of quality of the channel on the message duration relation to duration of an interval of correlation of casual process of dying down is for the first time established. Schedules of these functions are provided in article.
The conclusion is drawn that the theory of transfer of discrete messages in the channel with dying down of signals demands further development and specification.
- Zvonarev V.V., Paramonov I.Yu., Petrova I.S., Popov A.S. Algoritm upravleniya rezhimami raboty' bespilotnogo letatel'nogo apparata v sisteme peredachi informaczii // Sb. nauch. st. konf. «Studencheskaya vesna – 2016». SPb.: SPbGUT imeni professora M.A. Bonch Bruevicha. 2016. S. 599−604.
- Zvonarev V.V., Popov A.S. Veroyatnost' bezobry'vnoj svyazi, kak pokazatel' e'ffektivnosti kanala s zamiraniyami // Voprosy' radioe'lektroniki. Ser. Sistemy' otobrazheniya informaczii i upravleniya specztexnikoj. 2014. № 1. S. 103−106.
- Fink L.M. Teoriya peredachi diskretny'x soobshhenij. Izd. 2 e. M.: Sov. radio. 1970. 728 s.
- Makovij V.A., Chupeev S.A. Optimizacziya protokolov peredachi danny'x po KV kanalu // Nauchno-texn. sb. «Teoriya i texnika radiosvyazi». Voronezh: OAO «Konczern «Sozvezdie». 2010. № 2. S. 92−101.
- Kalinin A.I. Raschet trass radiorelejny'x linij. M.: Svyaz'. 1964. 268 s.
- Kamenskij N.N., Model' A.M., Nadenenko B.S. i dr. Spravochnik po radiorelejnoj svyazi / Pod obshh. red. S.V. Borodicha. M.: Radio i svyaz'. 1981. 211 s.
- Karpov I.G., Gribkov A.N. Osnovy' radioe'lektroniki i svyazi. Ch. I. Osnovy' optimal'nogo radiopriema: Ucheb. posobie. Tambov: Izd-vo Tambovskogo gos. texn. un-ta. 2009. 80 s.