THE HOTELLING DETECTOR USING QUADRATURE CHANNELS DECORRELATION

Introduction. The probability index of false alarm and its stability under varying and unknown interference environment represent important characteristics of radar detection systems. Presently, the problem of false alarm probability stabilization is solved, as a rule, using intellectual capacities of the human operator. However, the automated detection systems introduction does imply an urgent task of developing and implementing detection algorithms, providing the false alarm probability stabilization under conditions of a priori unknown interference environment without human operator involving. Analysis of recent researches and publications. In the context of Gaussian noise when a priori unknown covariance properties, the false alarm probability stabilization problem can be solved using the Hotelling’s resolving statistics [1]

Introduction.The probability index of false alarm and its stability under varying and unknown interference environment represent important characteristics of radar detection systems.Presently, the problem of false alarm probability stabilization is solved, as a rule, using intellectual capacities of the human operator.However, the automated detection systems introduction does imply an urgent task of developing and implementing detection algorithms, providing the false alarm probability stabilization under conditions of a priori unknown interference environment without human operator involving.
Analysis of recent researches and publications.In the context of Gaussian noise when a priori unknown covariance properties, the false alarm probability stabilization problem can be solved using the Hotelling's resolving statistics [1] 1 where [ ] -2N -parametric bloc vector, formed with the counting of input signals' quadrature components I X and Q X at N adjoining reiteration periods; T -threshold providing the required value of false alarm probability F .On the basis of conditional probability distribution density of statistics (1) given at [1], we can obtain ratio of the false alarm probability F of and correct detection D when the detector using the resolving statistics (1) -detected signal quadrature components' vector; ( , ) ( ) ( ) / ( ) B p q p q p q = Γ Γ Γ + -beta-function; ( ) q Γ -gamma-function; Thus, the potential false alarm and correct detection probabilities implemented when the interference parameters are known, may be derived from the relations given at [2] 2 0 , ( ), 2 Increasing the rate of adaptive detectors' characteristics convergence, -and in particular, case of detector using statistics (1), -to the potential values can be achieved using a priori information about the interference covariance matrix structure at the stage of processing algorithms' synthesis.For example, the source [3] exposes that under the conditions of stationary noise and probing signals repetition constant period, there exist processing matrixes independent of the interference covariance properties, providing decorrelation, and in the case of Gaussian noise , also the independence of quadrature channels signals.
This research goal is to find matrixes which guarantee quadrature channels' signals decorrelation, at the same time that to develop on the basis of proposed adaptive detectors' structural schemes changes, the detection characteristics tending to potential values reaching.
Main research description.The considered processing matrixes class include the matrix where I -the unit matrix of dimensions ( ) , where all components of lateral diagonal are equal to one unit, and all others are equal to zero.
Applying to vector X the transformation W , we get vector ( ) [ ] Taking into account that matrix the resolving statistics (1) upon effecting the W transformation, can be represented as where 11 ˆY B -evaluation of covariance matrix 11 Y B .Evidently, we can observe that Gaussian interference influencing, the maximum probabilistic evaluation of 11 Y B matrix is determined with the correlation where -evaluations of covariance matrixes at every quadrature channel.
V.A. Averochkin, А.V. Troyanskiy.The Hotelling detector using quadrature channels decorrelation.Introduction of automated radar detection systems makes it an urgent task to develop and implement detection algorithms which provide false alarm probability stabilization for a priori unknown interference environment without the involvement of a human operator.In terms of Gaussian noise with a priori unknown covariance properties the problem of false alarm probability stabilization can be solved by using Hotelling decision statistics.Using the Hotelling statistics the relations for the false alarm probability and correct detection probability are obtained.To increase the convergence rate of the characteristics for adaptive detector using the specified statistics to potential values we propose the processing matrix that provides quadrature channel signals decorrelation.Hotelling decision statistics considering the proposed conversion is obtained.The examples of implementing the proposed Hotelling decision statistics generator using quadrature channel signals decorrelation at the level of structural schemes are given.The detection procedures characteristics with and without the use of quadrature components decorrelation are compared.
Keywords:automated radar detection system, Hotelling decision statistics, quadrature channel signals decorrelation.