Nonstationary signals appear often in real-life applications and many of them can be modeled as polynomial phase signals (PPS). High-order ambiguity function (HAF) was rst introduced to estimate the parameters of a single component PPS. But due to its high nonlinearity, HAF has not been widely used for multi-component PPS which appear for example, in Doppler radar applications when multiple tar...

Multistatic radars utilize multiple transmitter and receiver sites to provide several different monostatic and bistatic channels of observation. Multistatic passive and active systems can offer many advantages in terms of coverage and accuracy in the estimation of target signal parameters but unfortunately their performances are heavily sensitive to the position of receivers (RX) and transmitte...

Economists studying choice with partial knowledge typically assume that the decision maker places a subjective distribution on unknown quantities and maximizes expected utility. Someone lacking a subjective distribution faces a problem of choice under ambiguity. This article reviews recent research on policy choice under ambiguity, when the task is to choose treatments for a population. Ambigui...

About the sign ambiguity in the evaluation of Grand Canonical traces for quasi-particle statistical density operators. Abstract A simple and general prescription for evaluating unambiguously the sign of the grand-canonical trace of quasi-particle statistical density operators (the so-called sign ambiguity in taking the square root of determinants) is given. Sign ambiguities of this kind appear ...

We present a general information-theoretic argument that all efficient communication systems will be ambiguous, assuming that context is informative about meaning. We also argue that ambiguity allows for greater ease of processing by permitting efficient linguistic units to be re-used. We test predictions of this theory in English, German, and Dutch. Our results and theoretical analysis suggest...

This paper derives the extended ambiguity function for a bistatic multiple-input multiple-output (MIMO) radar system, which includes the whole radar system parameters: geometric sensor configuration, waveforms, range, range rate, target scattering and noise characteristics. Recent research indicates the potential parameter estimate performance of bistatic MIMO radars. And this ambiguity functio...

The purpose of carrier phase ambiguity resolution is to improve upon the precision of the estimated GNSS baseline by means of the integer ambiguity constraints. There exists a whole class of integer ambiguity estimators from which one can choose. Members from this class are, for instance, integer rounding, integer bootstrapping and integer leastsquares. In this review paper we will present the ...

Global navigation satellite systems (GNSS) are well suited for attitude determination. In this study, we use the rotation matrix method to resolve the attitude angle. This method achieves better performance in reducing computational complexity and selecting satellites. The condition of the baseline length is combined with the ambiguity function method (AFM) to search for integer ambiguity, and ...

Today’s imaging systems today frequently have digital components, and some image processing is done in the camera. The potential for dramatically increased perfor­ mance is not realized, however, until the complete imaging system, including the optics and signal processing, is designed as a coherent whole. In such a system, the optics produces an intermediate image, and the final image is produ...

We consider the problem of estimating the Doppler shift and rate of a linearly modulated digital signal subject to time-selective Rician fading. We derive the Cram er-Rao bounds for the parameters; we propose an estimator, based on the Higher-order Ambiguity Function (HAF), and show that it is consistent. We also establish some interesting results in the context of estimating the parameters of ...