A. P. Trifonov

Reception of a Signal with Unknown Duration

The maximum likely and optimal (Bayesian) algorithms for detecting an arbitrary-shaped signal observed against the background of Gaussian white noise and for measuring the duration are synthesized. Exact expressions for the characteristics of the maximum likely algorithms are found. The characteristics of the Bayesian algorithms are obtained using computer simulations.

Efficiency of estimating duration of a signal with unknown amplitude

Quasi-likelihood and maximum likelihood algorithm for estimating duration of a signal with arbitrary share and unknown amplitude are synthesized. Operation efficiency characteristics for the synthesized algorithms are determined. Operation of the synthesized algorithms is verified and applicability limits for asymptotic expressions are obtained using computer emulation

Exact formulas for computation of reception characteristics of a signal with unknown appearance and disappearance times

We consider the performance of the maximum-likelihood algorithm for detection and measurement of appearance and disappearance times of an arbitrary waveform signal observed against additive white Gaussian noise. We find exact expressions for detection error probabilities and densities of estimated appearance and disappearance times.

Optimal Detection of a Signal with Unknown Appearance and Disappearance Times

We obtain maximum likelihood and optimal (Bayesian) algorithms for detection and measurement of moments of appearance and disappearance of a signal having arbitrary shape and observed in additive white Gaussian noise. Asymptotic expressions for characteristics of the maximum likelihood algorithms are obtained. By means of computer modeling, characteristics of the Bayesian algorithms are found.

Amplitude estimation of signal with unknown duration

Quasilikelihood and maximum likelihood algorithms for estimating the amplitude of arbitrary waveform signal with unknown duration have been synthesized. Characteristics of the synthesized algorithms have been also found.

Characteristics of estimating the amplitude of ultrawideband quasi-radio signal

Thesynthesis and analysis of the maximum likelihood algorithm for estimating the amplitude of ultrawideband quasi-radio signal with unknown amplitude and phase have been performed. The duration of the specified signal can amount to several periods or a fraction of the period of harmonic oscillation. The characteristics of the classical maximum likelihood estimate of the amplitude of a narrow-band radio signal were found while receiving an ultrawideband quasi-radio signal. The conditions of applicability of the model of narrow-band radio signal were defined for solving the problem of amplitude estimation with the specified accuracy.

Estimation of the number of orthogonal signals with unknown non-energy parameters

The synthesis and analysis of an algorithm for estimation of the number of orthogonal signals with unknown non-energy parameters have been performed by using the maximum likelihood method.

Quazi-likelihood estimation of motion parameters during the target probing with a sequence of optical pulses

Characteristics of quasi-likelihood estimates of the target range, velocity, and acceleration have been obtained during the probing with a sequence of optical pulses. The losses in accuracy of quasi-likelihood estimates as compared with the accuracy of maximum likelihood estimates were also found.

The efficiency of detecting images with unknown coordinates and area

The synthesis and analysis of a maximum likelihood detector of images against the background of spatial noise have been conducted. The losses in image detection efficiency caused by a priori lack of knowledge of the image coordinates and area were studied.

The efficiency of detecting an image of object moving in the unknown direction

The maximum likelihood algorithm for detecting a nonuniform image of the space-extended object moving in a priori unknown direction has been synthesized and analyzed with due regard for the background shading.