JPRS ID: 8341 TRANSLATIONS ON USSR SCIENCES AND TECHNOLOGY PHYSICAL SCIENCES AND TECHNOLOGY

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APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 16 !.lARCN 1979 m m (FOUO i6179) i OF i APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOR OFFICIAL USE ONL.Y JPRS L/a341 16 March 1979 TRANSLATIONS ON USSR SCIENCE AND TECHNOLOGY PNYSICAL SCIENCES AND TECHNOLOGY (FOUO 16/19) U. S. JOINT PUBLICATIONS RESEARCH SERVICE FOR OFFICIAL USE ONLY , APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02/48: CIA-RDP82-44850R000100034444-9 NOTE JPIt5 publiciCinns contain infarmAtion primarily from foreign newspapers, periodicals and books, bue xlsu irom news agency eransmissions and broadcastg. Marerials irom fnreign-language sources are Cranslared; ehose from English-language sources are transcribed or reprineed, with the original phrasing end other characCerisrics rcCained. 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K r COPYRI(:EiT LAWS AND REGULATIONS GOiVERNING OWNERSHIP OF MATERTALS REPRODUC:.D HEREIN REQUIRE THAT DISSEMINATION - OF TtiIS PUBLICATION BE RESTRICTED FOR OFFICIAL USE ONLY. APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 lflliLI0G12Ai'NIC OA7A L It�~,)rt Nu. 2. 3. Itrripicnt'e Arrrseiun Nti, sNEEr rRS t./8341 A. u i en.l 'mq ii 5lcputt Rlr TItANSt.A't'1UN5 UN U55k SGLLP,CI: ANll TLCItNOLOCY - PHYSICAL 16 March 1979 SCLl:NC1:S ANU 'l'ECIINULUGY , (FOUO 16/79) b, 7, lwhrnk1 8. Ner(urming Orgunfmation Rcpt, No: 9. 114-rlitrminy, lhtianiiatitm Y,u;io ;tnJ AJJrcy4 107Project/Tuek/Wutk Unit No. JoinC Publicatione Resea-rch 5ervice tODU NorCh Clebo ROlld 11. Cuntroct/Grent No, ArlingC,on, Virginis 22201 2. ~rmuwring Ihtiamiration Namr nm1 Addre.r 13. 1'ype of Repott dt Petiod Covcrad AR ihovc 14. 115. ',upqJrnu niauy Nult-, 116. ~\I~~.~~.~~ i�. 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I,ONTENTS PhGE , ELECTRONIC9 AND I;LECTRICAL ENGINE'ERLNG - Spatial-Time Procesaing of Radio Signals in Radio Measurement 3ystems in the General Case (Review) (I. Ya. Kremer; C. S. Nakhmans on; IW'L RADTOII,EICPRONZKA, , Nov 78) 1 The Synchronous Excltation of the Primary Harmonic of a Field With a PL-riodic Structure by an Incident Nonrelativistic Flaw (G. A. Alekseyev, et al.; IVUZ RADIOIIIIfiPRONIKA, Nov 78) 18 Postdetector Storage in Signal Detection Channels . (Yu. L. Mazor; IVUZ RA.DIOELEKTRONIKA, Nov 78) 24 Processing a Signal With a Ra.ndom Delay Using a Digital , Matched Filter - (I. P. Knyshev; IVUZ RADIOELEUROIVIKA, Nov 78) 31 The Noise Immunity of the Optimum Detection of Fluctuating Signals in Noise of a.n Unknawn Level . (K. K. Vasillyev; IVUZ RADIOEI,FKTRONIKA, 'Nov 78) 34 - The Reflection of a Quasicontinuous Signal From the Surf,ace - of the Earth at Small Grazing Anglea (L. F. Vasilevich, N. A. Vinogradov; IVUZ RADIpLEKTRONII{A, Nov 78) 39 Modeling the Processes in a SelP-Cscillating System Which Is Acted Upon by a Reflected Delaying Signal � (V. G. Lysenko, A. R. Niileslavskix; IW'L RA.UIpEI,EIMpNIKA., - Nov 78 44 - a- (aii - UssR - 23 s& T FoUoI FOR OFFICIAL USE 0'VLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOR OFFICIAL USE ONLY - CONTENTS (Continued) Page - GEOPSY8IC8O ABTRONOMY AND BPACE ~ Corpu.scular Model of Gravitation end Inertia (IC. Ye. Veselov; PR710GAUNAYA aEOFIZ]:KAp No 87) 1977) 49 Methods of Eatimsting the Accuracy, Network Density and Isoanoma].y Gross Section of a Gravimetric Survey (s. P. 3urovtsm; PR.IiQADNAYA QPOP'IZIKA, N0 87, 1977)� 66 _ PUBLIGATION3 List of Soviet Articles Dealing With Compoai.te Mater3als (GpgUDARgTVM1Nyy gQNLLTEi' SOVETA MINISTROV SSSR PO ~ NAUKE I TEKHNM. AKADIIMYA NAUK SSER. SIGNAL' NAYA INFaMSIYA. KQMPOZl'PSIONNYYE MATEEtTALY., No 24, 1978) 78 a - b - FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02/48: CIA-RDP82-44850R000100034444-9 FOR 0FF'ICIA1. U5E ONI,Y ELECTRONZCS ANU ELECTRICAL ENGZNEEkTNG UDC 621.391.161 SPATIAL-TIME PROCESSING OF RADIO SIGNALS IN RADIO MEASURIIMENT SYSTEMS IN THE GENERAL CASE (REVIEW) Kiev IVUZ RADIOELEKTRONIKA in Russian Val 21 No 11, Nov 78 pp 3-15 [Article by I.Ya. Kremer and G.S. Nakhmanson, manuscript received following revision 10 May, 1978] . [Text] Optimal apatial-time processing of signals is considered in the general case, including t1ie location of the objecta and external interference sources being observed in both Che far field of the receiving antenna systems as well as in the Fresnel zone. Also analyzed are the possibilities of utilyzing information on the curvature of the wave frnnt of eignals and interfer- ence to increase the precision in the determination of - the location of the observed objects, increase the re- solving power of the system and discriminates signals from interference generated by external sources. Introduction - The baeic principles of the theory of optimal spatial-time processing of signals ir; determining the position of observed objects and the parameters - of their motion have been rather thoroughly worked out in the literature [11- 31, etc. However, specific results in this field have been primarily _ obtained as applied to the apecial case where the wave fronts of the signals in the external interference can be considered planar, i.e., the observed obJects and interference sourcea are located in the far field of the receiv- in$ antenna systems, something which is justified only when the following - condition is met: R.c R,,.== 2L cosep (1) where R is the distance of the radiation source from the center of the antenna; RA3 is the radius of the far field; L is the overall dimension of'the receiving antenna system; 0 is the angle between the normal to the plane of the antenna and direction to the source; a is the wavelength. - FOR OFFICItiI. USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02/48: CIA-RDP82-44850R000100034444-9 F'OR OFFICIAL USE ONLY The eEfort Co increase the resolving power o� radio measuremenC systems _ and, relatad to this, the trend towards the uae of large aneenna syatems - auci t:he mastery of increasingly ahorter wavelengths, as well as the use of - _ diversiCy receiving systems [4, 51 is leading Co the fact in a number oE cases, condieion (1) is not met and it is impossible to consider the wave ' fronta of the signals heing processed to be planar ones. T us, the basic relAtionships derived for the case of plane electromagnetic waves are not - applicable to the analysis and synthesis of optimal spaCial-time signal procesaing algorfthma in a number of radio measurement systems and the theory of several auch systems (mulCiposition radar systems [5], hyperboli.c radio navigation systema [6]; etc.) are at times developed independenrly of the general theory of spatial-time processing signals. This makes the analysis nf such signals diff icult based on uniform methodological principles of optimal recepCion theory, as well as the estimation of the closeness of their chAracteristics to the potential achievable ones and the determinaCion _ of ways of optimizing them. What has been said above can also apply to sonar systems. For this reason, an urgenC problem is the generalization of theory of optimal spatial-time processing for the case of the recepti.on of aignals with both planar and epherical fronts, i.e., for the general case - of the location of the obaerved objects and external interference sources _ in Uoth the far field and the Fresnel zone of the receiving antennasl. In this treatment, the electromagnetic field of the signal has an addiCional parameter (as compared Co the case of a plane wave), the curvature of the wave front, which can be employed as a source of information. For small sized ("point") signal sources, the curvature of the wave front is uniquely related to the range to the source. With suitable processing of the signal, this allows for the realization of the followirig additional capabilities, which are m3nifest more strongly, the greater the ratio of the dimensions of the antenna system to the range to the signal and interference sources, - and the amaller the wavelength: --The spatial resolution of the objects with respect to range, by virtue of = the difference in the curvature of the wave fronts of the signals generated by them [2, 7, 81; --Tlie discrimination of the useful signals:from interference generated by external sources, by means of selection based on the curvature of the wave Cronts [9]; --7'lie determination of the range of "point" signal sources based on the curvature of the wave fronts; 1 I7or multipoaition measurement sysrems, the antenna is understood to be the set of antennae of all the receiving statians. 2 FOR OFFICItiI. USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02/48: CIA-RDP82-44850R000100034444-9 FOR OFFYCiAL U5E ONLX In l�}inse active radar sysrema, where the ran$e is measured based on the gignal delay time, the uae of a supplemental independent information source wi11 permit increasing rhe precision oF Che range determination [10, 11, 12, 13, 14]2. This paper is a survey of the basic principles And specific features of the optimum spnCial-t�Lme proc:essing of signals in the general case, including the proceasing of both plane and spherical waves, and a brief analysis is given of the poCential characteristics of such processing (resolving power, = noise tmmunity, and precision in the derermination of the location of nbjects). _ This ttnalyais is based on both published and new resulta. To aimplify the mathematical derivations, the treatment uses the example of n plane problem, ' where the antenna system is oriented along one of the cooroinate axes, while the objects and interference sourcea being observed are located in the same plane. The basic: governing laws ascertained using the plane problem example - are alsn jueCified when the objects and interFerrnce sources being obaerved are posiCioned in three-dimensional space, as well as for antennas of any size (linear, planar, three-dimensional). _ The Ambiguity Function of a Space-Time Signal and the Spatixl ResoluCion Posibilitiea A deecription of antenna systems and signaZs, geometric re7ationships. An antenna system with an overall dimension L and a center at the origin of the coordinates is oriented along the Ox axis (Figure 1). The geometry of the antenna system and the gain distribution in it are defined by the aper- ture function i(x) (3]. Basically, two forms of the functions i(x) will be - considered: a function corresponding to a continuous linear aperture wi.th uniform gain (I(x)12 = I when Jxl j L/2; II(x)12 = 0 when Ixi > L/2 and the n - discrete function l1(x)1zaEb(x-xr), , where xi are the coordinates of the receiving elements. A continuous aperture for the case of reception in the Fresnel zone is samewhat of an idealization, however, such a representation of t(x) permits the derivation of the basic relationships in compact form, while the numerical results, as calculations show, practically coincide with thie results obtained for an antenna array consisCing of a large number of isbtropic elements with spacings between adjacent elements less than A. The diiscrete function II(x)J2 ia a sufficiently good descripCion of an antenna arxay of isotrapic (nondirectionxl) elements with an arbitrary number of 2 Data on an active radar system are given in [15j, in which the range meaeurement is based on the curvature of the wave front and the informa- tion on the time delay is not used. 3 FOR OFFTCIkL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02/48: CIA-RDP82-44850R000100034444-9 FOR OFFICIAL USE ONLY Pt 44 z0 80 dp~ PNC. 2. 0 Figure 1. Figure 't. _ e.lemenCS and arbitrary spacings between them, as well as�of the anCenna systems of mulCiposition radio measurement system3 under the same,conditions and with relatively smAll anrenna dimensions at the individual receiving stationa. Let the observed object take the form o� a smaXl (point) isotropic radiation ~ source, located at the point Mp with coordinates of R and 0. The �orm of the signal radiated by the object (for the case of passive radar) or the sounding s ignal (in the case of active radar) is def ined by the eapression: so(~a Re{so(t)} - Re {l!(~ ll�g}, (2) where U(t) is the complex envelope of the signal. If the sounding signal is radinted from point 0, then when there are no distortions in it in the pro- ' pagation process and the corresponding normalizing of the amplitude so(t), the spaCial-time signal being processed has the form: _ s(t,X)=aol(x)r~ ) sort- R ~~~X~ll~a'', (3) ~ where �p is the random initial phase which is uniformly distributed over the range [0, 2w); r(x) is the range from the object to point x of the receiving antenna, equal to r(x) = r(x, R, A) = jl R= x1- 2Rx si n 6, - (4) ~ ap is the amplitude of the received singal at the point x= 0. Under the ~ same conditions, in the case of passive radar, if the time is read out with respect ta the aignal arriving at point 0, the signal being processed has the farm: s(t,x)-QoI(X)rR) sort_. r(X)^ R 1lpm.: 1 1 (5) r(x) at values of the range R which considerably exceed the overall dimen- sions of the antenna system L, can be approximately represented by three terms of series (the Fresnel approximation): 4 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02/48: CIA-RDP82-44850R000100034444-9 FOR OFFICIAi. USE ONLY _ r(x)_R_xsine+ X, cos=e 2R_ (6) The near boundary of the field in wtiich the k'res-al approximatien can be uaed is determined from the condiCion where a/16 does not exceed the value of the fourth term of series (6), and when 0= 0, the fifCh term of the series. R1 a R~,, ~ RA, r. S2 e, R3 > R~ns = Rn, L2 " 5 sin3 A 16 (7) The region of the locatien of the objecta being observed, Rdn LRnearl a R= RA3 [Rfar fieldl, Where it is necessary tn Cake into nccount Che sphericity of the wave fronta and the Fresnel approximation cnn be used, we - shall ca11 the Freanel region. _ The ambiguity funetion of a space-time signaZ. Let two observed objecta (signal sources) be posikioned at pointa having coordinates of (R1, 01) and (R2, 02). Taking formulas (2), .(3) and (5) into account, and neglecCing the lack of equality of the amplitudes of the signal at the di�ferenC points in , the antenna system, something which is permissible when RL Z> L[16], the range and direction ambigvity functions for the case of Active and paesive radars wi11 have the foZl.,owing forms reapectively [6]: /ri -I- R, - a --12a 2n . J I 1(X) 12 P~ I c r) exP I~(r, -f- R, - rs - R2) dx ~ p (Ri, e,, R,, e, 00 , f I t (x) Is dx (a ) . j(1 wll~ r r,- Rf- rz -I- Rz 1 eX 2n r- ~ ` ~ ~ P i j~ R, - r= RJdx P (R,, e,, R2, a,) _ , (9) . f I 1(X) pdx where pT(T) is the normalized complex autocorrelation funct3on of signal (2); rl and r2 are the distances from the signal sourres to the point x of the antenna system. In (9), the argument pT is the difference in the time shifts of the signals received by the antetina system at the points x and 0. For the case of noC very large antenna system dimensions (or a rather narrow epectrgl bandwidth Afc), the following conditions are observed ra - RZ ri - R, � ~ ' c - c ~fo ~ Ps (lo) and the ambiguity function (9) does not depend on the wave form of the signal s0(t). We shall introduce the following symbols: AR = R~_ R2 is the differ- - ence in the ranges of the objects being resolved; Rp = R 1R2 is the mean seometric value of the ranges. Then, in case direcCional resolution is im- posaible (01 = OZ = 0), taking approx imation (6) into account, the expressions 5 FOR OFFTCIAI. USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOR OFFICTAL USE ONLY - for the range ambiguity functiona for acrive (8) and passive (9) radar can be repreaented in the form P(oR,R,.e)= (1l) ( ii> N (2 ~R + xa AR cosa e eXP/ 2 eR xzAR 1 dx I f(x) la* � 2cRo ) ~ 2n( c 2cRo cos A1 , f (1(x) J1 dx  . ' . � a(eR,Ro.e)= (12) (12) 1(x) I~ Ps ( x~eR cosz9 ex 2n( x'~R 1 ~ _ \ 2~?0~ ) P 1~, 2Ro cos 8~dx f i f(x) I dx. _ - ' As follows from (11), in the case of active radar, the resolving power with respect to range is due to two �actors; --The resolution with respect to the delay time (time re3olution), determined by the 26R/c term in the pT argument (when (10) is met, the values of the func- tion pT are determined by this term alone); --The resolution due to the difference in the curvature of the wave fronts of the signals (spatial resolution). In the case of passive radar, the range resolving power is due only to the spatial resolution. Formula (12) shows that the range resolving power due _ to the curvature of the wave front of the signals increases with an increase _ in the square of the ratio of the overall dimension of the antenna system L to the distance to the objects being resolved Ro, with a widening of the signal snectrum and a decrease in the wavelength. For a linear antenna of length L with uniform gain, if condition (10) is met, (12) yields the following [2]: at. (oR.Ro, e)=c(Ya )/Ya (13) . ~ where C(x) = c:os n 2 dt is a Fresnel cosine integral, a==eRL2cos~/(2a~Ro). The grapli of the function pL(AR, Rp, 0), determined by (13), is shown in Figure 2. The width of this function at the 0.5 level is determined by the expression s - dRo, a- LZ ~2 e k - 16 Ro/Ra,. (14) 6 FOR OFFICIkL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02/48: CIA-RDP82-44850R000100034444-9 FOR OFFICrAL USE QNLY Formulu (14) ehowa thaC in syatems with narrow band signals, reaolurion with respect Co the curvAture of the wave front can be effective only at ranges aign3ficantly less than the far field radius of the receiv~.ng anCenna system. _ Tlte 1aCrer condition is usually met for mulCipoF;itior: radio systems. In such radio syaCema, the values of the range Ro Are of the same order of magnitude as the overall dimens:Lons of the antenna system L[5]. In thia case, the - range resolution inCerval runs Co units or tens of wavelengths, i.e., an exCremely high spatial resolukion can be achieved. 'Phe failure to meeC con- = di,tjoil (10) leads to an additional improvement in the reaolution wiCh respect - to the curvature of the front. Optimal Spatial-Time Processing and the Discrimination of 5ignals from _ Interference We shall cQnsider signal processing for the case of activA radar wiCh a small - :IsotrupIca1.l.y reradiating Carget, l.ocated at A point with coordinatea of (R, 0) (Figure 1). The following resulta, as applied Cc the spatial processing of - the signals, are also ~ustified for the case of passive radar for ama11 radia- tion sourcea. The signal (3) is received by the antenna against a background of internal antenna sysCem noise with a spectral density of N0, which is un- correlated at different points in the anterina system, as well as against a background oE noise generated by an internal, small isotropic source of gaussian white noise, located at point Mn having coordinates of Rn and On. The correlation functions of the inCernal and external interference at the antenna inputi have the form: . ; Bu (fi, tz, xs, xa) = 2-� 8(xi - xa) b(t, -tZ); B., (ri, ta+ Xi;z,) - , . . - N, ~ S rts ~ _ r"! r"=1 � . . . � (15) ~nftnZ ~ r; ~ \ c . EBBH � Binternall Where N1 is the spectral noise power density of the external source in the antenna aperture; rnl and rn2 are the distances from the noise source to the poi.nts xl and x2 of the antenna system, determined from (4). , Signaz processing atgorithms. Jhen receiving spatial-time signals with a random initial phase against a background of gaussian noise, the absolute - talue of the correlatiion integral of [1] is taken as the outpit of the optimal _ (in the aense of a criterion of the probability ratio) sigral processing system: Z= 21S u(t, x) v(t, x) dtdx I. cr~ c  ` (16) - where u(t, x) is an additive mixture of the signal and interference; v(t, x) - is the reference signal which determines the signal processi.ng algorithm; (T) and (L) are the time and space intervals, in which the signal processing is accomplished. The reference signal is defined by the relation: 7 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOR 0FFICIAL USg dNLY aCi~x,~~~ tt. x, xi)s(rit x') ~lditi, (17 ~ ) where s(t, x) ia the uae�ul signa1, while 0(e, e1, x, xi) is the inverae correlation Punetiidn of the ineer*erence, defined from the integral equgtion: ~ tf$ xis xj)B(lo tt# xo xI)dtidxi we 8(1 (x _xt~ (ig) ' f 1f where B(t, t1, x, xl)  B$H(t, el, x, xi) + Hn(t) el, X, xi) ip, the Cdl'r@I.A- _ tion function of the interference at the gntenna input. For a 12negr untenna with uniform ggin, the reference gignal which natifies equgtl.on (17) aesumeg the form: Q~t~x~~ 2 R~(t.R--i x Nt ! ~ { r x) c ) + i rjl (x) re (xj dx X s ~w - x l ~z~ R. ~ `t _ R `f' r(xi) - Q (xi)~- rn (z) ~i, (19) (19 ) and fnr the i-th receiving element of a diacretE antenna gysCem (antenna array)s ~ R$Ct-R ~~R;~ t-R`f' r" crn-f'Ln) (20) where 1V, ~~~r ~N~ ~1- No) ~ j ~ � . The firet terms on the right side of expreasion (20) and (19) describe pro- cessing matched to the received uaeful signal (3). In the folloaing, we shall call spatial-time proceising using such a reference signal matched processing. This proceeaing ie optimal only in the absence of noise generated by an external source. With matched proceaeing, the antenna ayatem ie "focused" with reapect to range and direction. The aecond terms in (19) and (20), eubtracted from the tirst, provide for optimal compensation of ex:irnal inte*ference. The essence of optimal apatial-.*.ime proceseing in the preaence of internal and external noise is more clearly aeen in the case ahere expansion (6) can be uaed, and the signal is a narrow band one in the spatial-timeaise aense (the correlation time of the signal 1/Afc is many times greater than the maximum value of the time ahift between the aignal values at the extreme points of the antenna system). For the case of range valuea which exceed the overall dimensions of the nntenna syatem, one can neglect the inequality of the amplitudes of the signals at different poinCs in the anCenna. Then formula (19) assumea the fnrm: / l - ~imp zsin9 z~ooss9 No ~ . ~C- -~11 - /J - PL (RQ. 9n. R. e x sin 6� x+ooss ~ 1 ~ (21, ~ ~ uP [J% --~~'~J w'Ca~ ~ 8 FOR OFFICIl1L USE ONL,Y APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOit OFFICtAL U5E ONdY e ahere � t P` (Rio ~tso 8i, O,~ ~ exp f x (ytn 0, stn Oj r~R lll (22) t ~ : If ( The expregsi,on which defineg the fdrm of the reference signa1 fnr the anCenna array is deCetmined on analogy aith (21), gubgtituting xi Pnr x. Ie ia ndt diffiCUlt to see from (21) that with gpaciai-narrow band signals, time and spatial prdcessing are separatedt the fgctor in front di the curly braces determineg the optimum timewise pxoceseing nf a signa1, and the expressinn in the curly bracee dptermines itg spatial procesaing, whieh rpduces to the matched epatial proCeasing of the ugeful end interference signblg, end the eubtraction from the reeulte of the firet operation of the xpeult of the second. The subtraction ie cnrried ouC with the areighCing Pactor 1316L(ittt, Ott, R, 0)/ /(Na + N1), defined by the mutual pogieidning of the earget and the noiae source, ao weil ae the relationehip af the external and internal noise inCen- sity. Where eeverel pxternal noige gnurces gre prespnt, matched epatial pro- ceesing should be cgrried dut for each source, jtgt ae in (19), vith weight- ing Cneffi4iente Which depend on the relationship of che intena'iCiee of the noige sourCea and their mutual arrangement (9). Uaually, the coordinates and intensities of the noiae eourcn_s are unknown beforehand, and for thie reagon, they should be determined by the proceseing system in the process of generating the reference eignal. The design af guch processing eysteme ig possible by meana of ueing the principlpe analyzed in (Z, 17j. The suppreaeion of noipe generat8d by e.xtgrnaZ aourcee. The effectiveneas of the suppresaion of naise generated by external eourcea can be evalugCed in terms of the eigngl to noiae ratio at the outpuk of the procegeing system. The poWer sigttal to noise ratio for the case of apatial-time signal process- ing is equal to [1]: x) o(t. x) dldzl. (23) To eatimate the level o� external noise suppression, we ahall introduce the following coefficiente: k � 9'/90; ! ~ 9'/9'0,,� - (24) ahere q2 is the output signal to noise ratio for the case of optimum procesa- fng of a signal with aspherical front againat a background of internal and external noise; qA, ie the same for the optimal pruceasing of a signal with a plnne wave front under the same conditions; qg applies in the abaence of external noiae. The coefficient k indicates the degradatiun of the output aignal to noise ratio by virtue of the presence of external noise; the coef- ficient Z is the level of suppresaion of external noiae through the use of information on the curvature of the wave Pronts. 9 FOR OFFICItiI. U5E ONI.Y APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOEt OFFICIN. USE ONLY In the dptimal proceseing of ngrrow band signalg in a linear nnCenna of lengeh _ L, formulg (23), taking (21) into aCCOUnt, yieldg the gollowing [9]: ~ k':' 1.._ N . N ~ AL (Iln~ en ~ E2~ 1m r 1.}. .k 1 k. \ / (2 5) The valuee of the noefficients k and I a,�e ehown in Figurea 3a gnd 3b (ehe pI9 , where RA~ ig the far field snlid 11nes) ge a functinn of Y~. 17-Rn R'" R rndiug of (1), for the cgee where the angular coordinates of the noiee source and thu target coincide (On - 0), and geting of thp external noise is pogsible only through the diffQrence in the curvature of their aavefronts. As followg from Figure 3, w3.th a eignificant difference in range betveen the eignal and noise eourcea (Y � 1) ka 1, i.e., Che external naiae can be suppreseed almoet completely. in this case, the adventage gained in the gignal to noise rgtio ae Compered Ca the cgee of processing a plgne wave Z ie approximgtely equal to the rgtio of the speCtral densitiea of the external and internal noise at the antenna aperture. The gain falls off in etep with a decrease in the curva- ture of the wave fronti. It Was nnted above that the realizatior of optimal spaCigl-time processing of eignals Where exCernal noise aources are present ig rather complicated. Por thig regeon, it ie of interest to aesese Che pogeibilities of euppressing external noiae for the case of eimpler (fram a design viesapoint) matched proceseing. In this case, the coefficiente k and Z are defined ns: k� N~ 1� (1-- J-1 k. (26) Ni~-N,IP~(Re. B.. R, e)P ~ ` N0 l 7'he values of k and Z With matched processing for the case of Aff � 0 are shown in Figuree 3a and 3b by the dashed line. A comparision of theae curves With the curvea for the caee of optimal processing ahowa that aC extremelq emnll (Y = 0) and extremely large (Y > 20) curvatures of the wave front, matched processing provides for iipproximately the same degree of external noise suppreasion as eptimal proceeeing, while in intermediate cases (1 < Y< < 20), optimal processing is more effective. Figure 4 illuetrates the suppresaion df external noise for the cgse of optimal apatial-time processing fn multipoeition radio syatems, where the aumber of receiving pointe is small, while the spacings between them are � A. The cutwes are plotted for the case where there ie no gaCing With respect to direction (0ff = 8), While the noise source is located in the far field (Y U Rgg/R). The dashed linee apply to a three-position system (xl --0.45 L, x2 = 0, x3 - 0.55 L), and the solid lines apply to a five-position system (xl ! . ~-0.45 L. x2 - -0.2 L, x3 - 0, x4 - 0.25 L, xs - 0.55 L). The curvea in Figure 4 atteet to the fact that in multiposition systems, the input signal/ - noise retio expressed as a lunction of Ya Rgf/R is of an oscillating nature. An increase in the number of receiving positions leads to a emoothing of the oecillatione. 10 FOR OFFICIAI. USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 - FUR UFFICIAL USE ONLY Fur ehe cusp of acCive radar: ~ : c.' 4 (r16 ' [1+ Ls Ccoss 9 ` ~q r , ~ sin! Al 090 ~ ~ II~ +11 o u 16 ~ cos' 9(7 - 31 s ins 6) L-'-~ L' cos' 9 . (28) In Cormulgs (27) and (28), L2 and L4 are the normalixed gecottd gnd foureh moments nf the square nf the aperture functionslI(x)12 (1, 31, determine2 ~ by the geometry of the gntenne eyatem gnd the gain dieCribution in it; q8 is the signal/floi8e rerfo; c is the gpeed of 1ight; n2 ie the gquare of the equivalenC width of the etgnal epecerum, defined as the second central moment of the epectrum. The formulag gre de.rived ueing the approximate ex-, pansion (6). . 1 ~ ~ l4' ro, ~ h'igure 5. For the caee of range meagurement based only on the curvature of the wave front, the meaeurement error as fo11oas from (27), is prnportional to the wavelength a and the squarp of the ratio of the range R to the overall eize of the antenna L, and the error depends slightly on the epectral width of the signal. Shown in Figure 5 is the nottinalized dispprsion of the range measurement ag a function of the ratio L/2R for a linear antenna of length L. aith a uniform gain dis- tribution, and for an equally apaced antenna grray of the eame length consisting of three elements where (tta/Wo)Z � 1. Zn act:ve radar, for the case of optirial spatial-time processing of the signals, the range is determined by meang of the joint utilization of the information on the delay time and the curv;iture of the Wave front of the signals. To eatimate the influence of wave front curvature information on-the precision of range measurement, shown in Figures 6a and 6b are the rgtio of the dispersiona of the range eatimate for the case of optimal apatial-time procesaing of the signals (vj) and for the cnge of ineasurement based on the delay time (oRO) for a linear antenna of lenRtli l. (Figure 6a) and for an -iqually spaced antenna arrey of the same lengtli (Figure 6b). As can be seen from Figures 6a and 6b, the use of wave front curvature informntion permisg a substantial increase in the range measure- ment precision when L/R > L/Rbound a 2 n � h'or ex,imple, ai[h n relntive spectral width of R3/wp = 10-6, the influence of the InEormation on ttie curvature of the Wave front begins to have a substantial rf[cct at ranges of R2 I 103L. M analysis of Figur.es 4, 5 and 6a ahoWa that tor [clentical vttlues of the output signal/noise ratio and identical overall JimenHionH of the antenna, the range measurement precesion when using "dis- persed" antennu arrnya ie higher than ahen using antennas vith a continuous 12 FOR OFPICIhI. USE ONLY I , APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOK OFrICIAL U5E ONLY 4 ~ l / i ~ / / 6 6 4 2 0 ~ t 5 /025rorr o c (al. N  ' i / / l1? ~10?5/0`r (b) K m VA i a ir5 ~ r3 I Q~ I ~ps 1 ~ ~ 42 J 0 12 510 2 5 /0 Y Figure 3. Figure 4. ; [fnsed on the values of the signgl/noise ratio at the output of the proceseing gyetem cdmputed from formulas (19)--(23), the probabiliey of detecting bn nbject by meung o� the wsll-known detection curvps cnn be determined. In Chig cnHe, iC is necessnry to consider Che fact ChgC xt gmall valuee of R/L, an increaqc: in thc range resolving power by virtue of resolution of the curvature of the wave front leads to an incregse in the number of resolution elements in ehe scanning field, and conaequently, to an increase in the false alarm probability. lletermining the Positiun of Objecte and Their Peremeters of Motion q! qc Q~ Q~ The posgibility of determining range based or, r'ie curvature of a wave froni arises wiCh spati.al-time processing of signals wteh spherical wave fronts. In passive radar sysCeme, this is the sole primary source of information con- cerning ttle range; in active radar :,stems, the information on the Wave front curvnture cmn be emplayed in con,junction with the information on the delay time of the signals to increase the precision in detennining the location of objects, and in aome cases, it cen be used independentl.y [15]. For the case of interference in the form of gaussian white noise, which is not correlated nt Chn different pointa in the receiving antenna system, as well as for large siKnnl/noise ratiog, the precision in the estiTaaCion of the range R using tlic maximum probability method is characterized by the following expression: For the case of pasaive radar Q'�1'o ~T 1((00)I + 11 L' - Ll)-t ; (27) 11 FOR OFFICItiI. USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOEt UFFICIAL 'J5C nNI,Y - nperture, und bcaomey higher the Hma11er Chci number of elementa nC the nrray. Hnwever, Enr lnrge vnlues nf L/J, a reduction in rhe number of 'e1emenCs af the array cnn 1ead to ambiguiry in tiic measuremenes which can ba eliminhted by menns df axpnnding the epectrum o� the signal being processed. The re- ~ quiremente placed dn Che signgl snectrum eo eleiminate measurement nmbiguity in tihe angular coordinaCes when ueing "disperged" arrAys in the general cage ax the positioning of the objecta being observed do noe differ dubsr.antinlly - i;xom the requiremenes which nre see when the objeCts are ldcated in the fnr field of the anCenna array. mhe ambiguiry phenomenon uf range measurcmenCs nrises in the spaCial-time processing of signals wieh a spherical fronC. Tt can Ue shown ehat ambiguity in the range measurement can ariae when receiving signnls with a lineur, equally spaced antenna nrray containing n elements, where n 4 ~ R ~og e) . (29) ;0 0,/64"M1 1,4 opt 6A, 0,! QI ~?R ~k `0 _ Q? Q< l/IR (a) � � (b) Figure 6. Figure 7. In paper [11], the potential p?-ecisian in the estimate of coordinates is analyzed for the case of an antenna of any size. A comparison of the results obtained in Chis paper for a circular antenna, with those results given above for n linera antennn ahows thut for the case of equal overall aize, the ad- v;uitahe gnined in precision by virtue of using information on the Wave.front curvuture ie approximaCely the same for both antennas. An anzilysis ot the precision in eatimating the angular coordinate of an object !n the genernl case shows that when receiving signals with spherical wave CrcintH, the potential precision of the determination of directions is practical- ly tite same As when recei.ving signels with plane wave fronts. Ignoring the wave front curvature in spatial-time processing of signals can le;id tn n substnntial degredation of the signallnoise ratio and the range me;tsurement precision. Thus, When R= 0.02 Rgf, the signal/noise ratio falls uEf by trns of timcs [11j. The range measurement precislon, ds a result of fniling to tnke into account the information coneained in the curvature of the - wave front, tor R s 25L and L/J = 100, decreases by ten times ahen 1i3/w0 ' = 10-3 and by 100 timea s.�hen ii3/wp - 10-6 (181. 13 FUR OFFICI/,L USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOR OFFICIAL USE ONLY _ The poCenCial possibilieies for increasing the accuracy of multipogiCinn radio sysCeme nperating in the F'resnel zong can be illuetrated by meane of compnring the precigion of range measurement in a range difference (hyper- bnlic) radio naviagaeinn systiem [6] and in a system with the same arrange- mene o� the receiving etatione, which carriea out the opCimal gpatiial-Cime proGessing oE the aignal. Shown in Figure 7is the ratio of the dispereiona nP the range esCimate oh itt a Cwo-base hyperbolic system with receiving sta- ttons at the pointa xl A L/2, x2 - 0, x3 - -L/2, gnd in a syatem which realizeg the opCimal processing of the gignals received at the same statione: 0o t _ (dg was determined on the basis of the relationahipa given 3n [6], and the vnlues uf oo t were determined from formula (29) twice. It can be seen from rigure 7 Chat the preciaion which can be attained in hyperbolic radio naviga- Cion systems ia extremely fo.r from the potenCial accuracy obtainable with optimnl coherenC processing of the aigngl. Ttte rclutionghipsggiven above were derived with the assumption that the signal/ noisc rntio is rather high, and the range eatimate ia reliable, i.e., the pro- bability of anomolous errors is neglectibly small.' With amall values of the piirameter R/L, the reaolving power with respect to range increases sharply by virtue of the resorution based on the curvature of the wave front, gnd cdn- sequently, the probability of anomolous errors also increases. In this case, higher values of the aignal to noise raCio can be necessgry to assure relia- bility of the eatimate than is true of the case of range measurement based only on the signal delay time. An analysie of this phenomenon ie given in the literaCure [19], the reaulte of which show that for signal to noise ratioa of q0 1 20, the increase in anomolous errors muat be taken into account at rcletively small values of ChL range (as compared to the dimensions of the antenna system) and at a relatively small signal spectral width (for tt3/wo _ m 10-3--10-4 when R 500. Thus, na a result of the anelyaig made here, precise and approximate formu- lns were derived w}iich are needed to egtimate the noise immunity of optimal detectidn of packeta of fluctuating sigaals in noise with an unknown disper- gion. - BIBLIOGRAPHY 1. Levin B.K., "Teoreticheskiye osnovy statisticheskoy radiotekhniki" ("The Theoreticel principles of Statisrical Radio Engineering"], Moscow, Sovetskoye Rndio Publishers, 1976, Book 3. 'l. 1'rokoE'yev V.N., "Obnaruzheniyc pachki signalov s neizvesCnymi parametrami - v shumnkh neizvestnogo urovnya" ["The Detection of a Signal Packet wt,th Unknown Purameters in Noise of an Unknown Level"], IZV. Vi1zOV - tAl)IUELEKTRONIKA (PROCEEDINGS OF THE HIGHER EbUCATIONAL INSTITUTES, W1DI0 FLECTRONICSJ, 1972, 15, No 10, p 1,234. 3. 1'rokof'yev V.N., "K zadache obnaurzheniya signalov v shumakh neizvestnogo urovnya" ["On the problem of Signal Detection in Noise of an Unknown Level"] � itADIOTEK}{NIKA I ELEKTRONIKA, 1969, 14, No 10, p 1,895. 3? - FOR OFFICIAI. USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOR OFFICIAL USE ONLY G. Krnmer C., "Mneemnticheakiye metody atatiseiki" ["Mathemntical Meehode of SCaCietiCs"] , Moecow, Mir Publiehers, 1975. 5. Grxdehteyn, I.S., Ryzhik I.M., "Tabl3Cgy integrglov, eumm, ryadov, i prnixvedeniy" ["Tablee of Integrale, Sums, 3eriee and Producte"), Moscow, Nauka Publ3sheYS, 1971. GOPYRIGHT: "Ixvestiya vuzov SSS1t - Rgdioelektronikg," 1978 8225 CS0:1870 38 FOR OFFICIAL 11SE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOEt dFFICtAt, U5E ONLY - =CTRONIC3 AND LLECTRICAI, Mt}INEEiING UDC 621.396.96 'CIIL 1tLF'!,L'CTInN Or AQUASICdN'1'INUUUS 5iGNAL FRdM 'CNE SUEtFACE 0F THC EAtt'I'H A'C SMALI. G1tAZING ANGLLS Kiev IVUZ ttADIdELl:KTItONIKA in Rusgian Vol 21 Na 11, Nnv 78 pp 133-135 (Article by L.F. Vuailevinh and N.A. Vinngrndov, menuecript received 14 Derembcr, 1977J [kext] in gtudyinK qrnundrpCurng, g gtatigeically r4ugh surfaGe ie usunlly emp.toyed itg the mndel of the reflecting nrea 11j. In thie paQer$ Chig surface lt+ treated na a�ilter wieh randomly changing characteristiCS.. SuCh an apprunc:h pcrmits the use of the well develnped toolg of parametric gyetemg Chcory. We shall write thc tieFlected signal in the form of the sum of the returne from the elemcntal areag: ,v r(9-~ 2~~'~ Q(9,)x(I-r,)&; d-~, r.~ where K(t, ti) is the reflection factor of the i-th reflecting area; AD is thesize of an elemental area, aithin the bounds of which one can coneider the reflection characteristic to be constant; c is the propagation velocity of the radio waves; Q(#i) is the shading futtctfon of (i): Q(#i) MQ(arc04n 2A� Qi ig the grazing angle; hg is the height of Che antenna. d lt is usually asgumed thnt the signal reflected from an elemental reflector clneK not inf.luence other signals. It Was noted in [2) that the setting of cuncllcicros ahich define the mutual influences of the elemental reElectors JneK nut produce uny marked change in the resulta. Taking this tnLo account, one cxn go to the limit Where At 0 and N s~ V(nw f Q(i)~U.s)x(t-t)ds, ~ attere Tmin end Tmax are the delay limts of the reflected aignels; k(t, T) � a~ l K ie the pulse characteriatic of the reflection of the aurface _ gegment. 39 FOR OFFICIl,L U5E ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOtt dFFtCIAL U3E dNLY IE n pulned Hignnl with an amplieude A nnd g period Tn [Tp] in uged gg the naunding gignnl, M x (J) �'I A(t - mTe) aP ("1W tI a.1 ehen the reflecred s3gna1 geswneg the furmt Ma M Y(0 f~' Q(t) R(f mTn, t) A(! - mT,, - t) uD Ir-'j'lfti (I - e7'n r' t)Mt. sfm� 0-1 Let dndther get of elemental reflectore be loegeed at a cereain distance n2. The signgl refiected from it wi11 bes stnra Yt~) ~ j QIti1R (I -o, t)x(f-n-S) di, where ~ 20 Whcn computfng the correlation funetion (Itlt) of the refleeted ai$na1, it ig ne~~ssary to congider the statiseical chnracterisrics of the roughness oP the reEleCting surface. Taking this into account, we t+rite the correlation f.uiiCCinn in the farm: I? p. c1 - J J y U, hJ Y(I - a M) Os Ut. MJ dhldhs Where N2(hl, h2) is the tWO-dimensional law for the distribution of the heightg. The assumption thut the diatribution of the heights of the pointe of the reElecting surface is close to a normal distribution is substantiated in - 11, 3, 4j. Considering W2(h1, h2) to be normal, following aeveral cwnbersome trangfo mations, the correlation function can be reduced to the form: N rr kt J J y( 3). Then the certainty of detecting the effective anomaly is practically equal to unity (4~(3) = 99.7 percent). Undoubtedly, detection of the eYfec:t - o� a mildly sloping structure with this certainty practically excludes the poasibility of missing it. But in the case of low strength of the effect this imposes quite strict requirements on the accuracy of the survey. In particular, the employment of seandard gravimeters ensuring a measurement error of 0.05 to 0.06 mgal can become simply impossible. And this, in turn, can restrain the introduction of gravitational prospecting in the practice oE prospecting work. In addition, the instructions do not give an answer to the question of the required observation network density and of the possi- bility of varying it in relation to the accuracy of the survey. Of course, in practice an attempt is always made to make more than three observations per profile within the limita of an anoznaly. But in each specific instance this number ia determined arbitrarily, In V.V. Kotlyarevskiy's method og x'elative e;-rors, eVidently for the first Cime in domestic practice precise relati.onships were establi,shed between the certainty of detecting anomalies and the accuracy and observation network density requixed for this. Typically, the relative error itself, Em = o/gm , 73 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOR OFFICIAL USE ONLY ie a value xepreaenttng the inverae og the eggective^eigna7,-to-noise ratio intxoduced by the tnetxuctf,ona (s m I/E Furthezmoxe, unltke the Instruc- tions, here thie value I8 not afixsd oie. xC can vAZy, being bound only ae the lower limtt (s t- 2). The asaigniqant oR 9 auCOmatically determines the required accuracy and obeervation network deneity. Furthermore, the cereainey og datecting the anomaxyr is dexined ae 0 w0(1/E Tn addition, this method 8saumea ehat it Ia pose3,ble to varyr the parameters of accuracy and obaervation network density while nutintaining the required certainCy of detection. On the whole thia method broadens the capabilitiea of gravitational proapecting in formulating d3fferent problems. 0f all the methods enumerated above, the moet effective, evidently, is A.A. Nikitin's method. x'his is explained by the fo11ow3ng reasona. First, here _ ia moaC aimply expreased the relat3onship between aurvey parametere and the certainty of eignal deeection. Unlike other methods, it can be used for detecting anomalies whose intensity is equal to the atrength of the noise and is slighter. Thia method ie the only one in which estimal::es are made with reference to area and in which the case of correlated noir,�e ia considered. Survey parameters are determined here on the baeis of an apriori asaigned cerCainty of detecting the aubject of the search or of prospecting. With assigned certainty, it is posaible to vary both the network denaity and the observation accuracy. A11 this makes it posaible Co recommend this method as the basic one 3n estimating aurvey parametera, in particular, in prospecting mildly sloping structures. Let us now discuas the certainty of signal separation againat a background of random non-correlated no3se. Generally, this certainty is determined by the accuracy and network denaity of the survey, the ratio of the useful signal and noise strength, and the law for variation of the strength of the useful aignal, and, as a consequence of all this, by the isoanomaly cross section and the survey acale. Formally, both in "Technical Instructior,a for Gravitational Prospecting Operatione" and in B.V. Kotlyarevskiy's method, the certainty is assigned by selecting the isoanomaly crass section. In the instructions this problem is solved on the basis of the principle that the cross section must equal triple the measurement error. Furthermore, a necessary condition for nutlining an anomaly is the presence within its limits of not less than thrr�e points obtained on independent trips. As far as the scale of the survey is concerned, it is determined on the basis oE its formal relationahip to the isoanomaly cross section chosen. The con- dition imposed on selection of the cross section assumes a degree of certainty _ in outlining anomalies with lsolines which is practically equal to unity (00) - 99,7 percent). But this concerns only anomaliea which are two times ~ greater in strength than the measuretoent errors. 0f couxae, this method cannot be employed fox the purpose of outlining anoma].i.es equal to and slighter than the noise. Tn othex worda, these anomali,es will be omitted, since they will not be ourllned. The employment of B.V. Kotlyarevskiy's method makes it possible in selecting the cxoss section to operate with the set of parameters of the anomaly to be 74 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 _ Fbtt OFFtCIAL USE nNLY lqntared. Tha ee],oeklnct og the cgaee ReGCi.on iCae]�t here dependm nn the apriori aesigned cextainCy wixh whi,ch wa Wish tp tao1ate the artomaly in quest4on, 0 m O(7./D And ehie coxtAinty, in turn, depando nn the eelected neCwork dansiCy, Che qccuxitcy of the aurvey and the elgnal-Co-noieg raCio (the ],aw o,t varl~tton of the strength nf Ctie uselux aigna]. Ie nesigned apriori, in th3s maChod). This has A d3tcect xe1nCionehip ro the problem of ieolaring low-etrengkh anomaliee. Actually, Chi,s ntethod eeCAbllehee the required quantitarive r.elntionshi,pg between the certainty of ieolating the effective anomely, survey parameters and the isoanonAly crosa section (survey ecale), for the case when the intensity of the effective anomaly ia commenau- rate witli the obeervation errnr, 0(],/DM ) d0(l) . The comparaCive analyeis of ineehods made fiere can be conducive to imprnving the geologica1 and economic ePfeceivenega of graviCat3anal prospQCting. zn conclusion, 1eC ue 311uatrate the cnpabil:leieg of these methods witli g epecifi.c example. We a8sume that the subject for proapecting is a mildly sloping sCrucrure with the following parametera: = Number of gravitationally active bnundaries 1 Excesa denaity wiehin 11miCe of graviCationally acttve boundary, Ap , in g/cm3 0.2 Mean bed depth of gravitationully active boundary, tl , in km Z - Axisymmetric aurocorrelation radiua of boundary, R, in km 2 Mean atatistical amplitude of structure, Z, in kmZ 0.1 Linear dimeneiona of anomaly of atructure, 2t 4 Mean statietical inteneity of effective anomaly, g, mgal 0.2 Maximum intensity, g, mgal 0.3 Ratio of autocorrela?ion radiua of noise to interval between neighboring eurvey pointa 1.5 1~ . . R 3)pa3 4) ~ 5) o ` ~ 6) np,~HerP ~ ~ a$ ~ a e a o ^ ci� x~ g ~ oaroe~HnwlT ~r.~ n~p:~~~ =O 00 ocs R p to ~G~ B ~ ry 3 p K,e ~ UtiTtllf."llblMfO npneMa A, A. }IttttgTtl80 p i ~ po ~ 0~ (If0 tt110t1(N,~tl) S C ba axx ce 7) lforpamaocn xnie- 0,07 0,05 0,10 0,05 0,05 0,10 0,15 peaux, uran 8) !'ycTor.i ceTtr, iac 1,5 1,5 2,2 - 2 94 x - q) 1(acmreG chewmi, I: 25 000 1: 25 CUO l: 100vU - , h 2,94 uran IO) C09Plll(9 p 0,25 0,25 0,10 AOCSU06jIHOCT6 DN- 11) J(OIIHMiA 1 1I 10 @a- IfOlt AF(OD41mm: Y1 :19,73 9J,fl9 95,45 100 V2 f)Si,i3 J3,02 i9,05 - - - - [IGey on following page] 75 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FOtt OFFICLAL U5E ONLY Key: J.. Paxameter 2. MeChode 3, Oiyen in Cechnical In- etructione, (by prQgtle) 4. B.V. KoelyAxevak3.yr'e meChod of re1,ative exrotca (by profile) S. K.V. alAdic3,yls method of QquaCing erroxe v and s (by pro�i.le) 6. Baeed on A.A. Nikttints theory of optimum recepe3.on (by area) 7. MsaauxeMsnt Gxxox, MSaI 8. Netwoxk denatcY', km 9, Suxvey ece;Ie 0 tngal 10. Cxoes eection, p 11. Certainty of IsolaCing ef4ecti.ve anom1y xn ehe rable are given the resulte of eetimatee by each method, wi.th an indica- Cion of the certainty of detecting, y1 , and ieolating, -Y2 , t1ae effecCive anomaly. Bibliography 1. Gladkiy, K.V. "Gravirazvedka i magnitorazvedka" [Gravitational and Magnetic Prospecting], Moecow, Nedra, 1967, 318 pagea with illuetrationa. 2. "Inatruktaiya po provedeniyu gravimetricheskikh rabot" [Inatructions on Carrying Out Gravimetric Work], Moecow, Nedra, 197` 46 pagea with illus. 3. Kotlyarevakiy, B.V. "Eatimating the Accuracy of a Gravimetric Survey and Selection of an Intelligent Obaervation Network and Gravity Isuanomaly Croas Section," PRIKLADNAYA GEOFI7.IKA, No 20, Moscow, Nedra, 1958, pp 34- 62 with illus. 4. Nemteov, L.D. "Vysokotochnaya gravirazvedka" [High-Current Gravitational ProapectingJ, Moscow, Nedra, 1967, 230 pagea with illus. 5. Nikitin, A.A. "Statistical DeCection of Slight Geophyeical Anomalies Against a Background of Random Noise" in "Avtoreferat diss. na soisk. uch, step. kand. tekh. nauk" [Author'e Abatract of Dissertation for the Academic Degree of Candidate in Technical Sciencea), Moscow, MGRI, 1967, 115 pages with illus. 6. Savinskiy, I.D. "Tabli.tsy vexoyatnostey podaecheniya elli.pti,cheskikh ob"yektov PrYamougol'noy set'yu nablyudeniy" [Tables of Probability of a Sub-Croas-Section Rox Elliptical Objects with an Oxthogonal Obaervation Network], Moecow, Nedxa, 1964, 36 pages with 3lJ.us. 7. Serkerov, S.A. "Tnvestigation of Optimal Transformations of Gravitational and Magnetic Anomalies" in "Avtorefcrat di.ss. na soisk. uch. step. kand. tekh. nauk," Moacow, MINKhiGP, 1965, 136 pages with illus. 76 FOR OFFICIAL USE ONLY ' [ APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2007/02148: CIA-RDP82-44850R000100034444-9 FoR orFrcinL crsE ornY . , 6. SuroytaeY, B.P. "High-Cuxxent Gxavltattona7. Pxoapect~z~g In Scanning and Pxoapsctin$ Mildly S1,oping Srructux~a In Che Centxal Rag~ons of the Ruasian Plzltfom," Pki1KGAANAYA. GFOF1ZxKA� NQ 65, MQSCOv, Nedxa, 1972, PP 151-163 wi.th illud. - COPYRIGIIT; lxtla,tel'srva Nedxa, 1978 8831 _ CSO: 81,44/0854A r 77 FOR OFFICIAL USE ONLY APPROVED FOR RELEASE: 2007/02/08: CIA-RDP82-00850R000100030044-9 APPROVED FOR RELEASE: 2047102108: CIA-RDP82-00850R000100030044-9 FUIt t1FF[CtA1, USI: (1NLY I'I I Iti I, I c:A'[' l UNS I,I:i'C Ul., SUViE'f AEtTICI.,ES DL:ALING WITH COMPO5I'i'E MATERIAIS Moscdw (;U5UUAKSTVE:NNYY KOMITL;T 50VETA MINI5TROV SSSR PO NAUKE I TEKHNIKE. = ni