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In this paper differences between Fisher Information Matrix (FIM) and inverse covariation matrix of normalized correlation estimations for white and colored noise are investigated. It’s shown that implementation of normalized correlation function estimation leads to modification of maximum likelihood estimation FIM elements, so in case of arbitrary energy affected parameter vector, variance of estimation by normalized correlation function maximization is not equal to Cramer–Rao lower bound. Statistical characteristics of joint Doppler stretch and delay estimation by maximization of normalized correlation function for signal with nuisance parameters are derived in this paper. It’s shown that normalized correlator is equal to wideband ambiguity function, but this method of estimation follows from Cauchy–Schwarz inequality without using energy conservation assumptions. Besides, it is proved that estimation of Doppler stretch and delay by normalized correlation function or WBAF of signal with random initial phase and gain is asymptotically unbiased and effective.

For pt.I see ibid., vol.12, p.2797 (1979). AC hopping conductivity calculations are performed using a method analogous to the one used in percolation theory for frequencies lower than those described by two-site models. An expression was obtained for sigma ( omega ) approximately omega f( omega tau c), f being a slowly decreasing function of omega tau c( tau c is a few orders of magnitude larger than the characteristic time in two-site models, tau 0 approximately 1/ nu ph). Over a wide frequency range sigma ( omega ) approximately omega s, with s

A theory is developed for the low-frequency AC hopping conductivity in disordered systems which accounts for multiple hops. The ideas of percolation theory are used to reduce the problem to a study of sigma ( omega ) (the frequency-dependent conductivity) in a cluster model. It is found that the size of the clusters increases with decreasing frequency and that sigma ( omega ) approximately omega s,s

In the temperature range 4.2 to 300 K under modulated 3.39 μm laser illumination, the dependencies of photoresponse on modulation frequency, as well as polarization and phase shift are measured in Cs2(TCNQ)3 single crystals. An interpretation of the results obtained is presented; the photosensibility and photocarrier lifetime values of less than 10−26 MΩ−1 W−1 and 10−14 s, respectively, suggest that the standard band pattern for Cs2(TCNQ)3 is unsuitable. [Russian Text Ignored].