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• W12192253 abstract "Signal processing has been playing a key role in providing solutions to key problems encountered in communications, in general, and in wireless communications, in particular. Time-Frequency Signal Processing (TFSP) provides eective toolsfor analyzing nonstationary signals where the frequency content of signals varies in time as well as for analyzing linear time-varying systems. This research aimed at exploiting the advantages of TFSP, in dealing with nonstationary signals, into the fundamental issues of signal processing, namely the signal estimation and signal separation. In particular, it has investigated the problems of (i) the Instantaneous Frequency (IF) estimation of Linear Frequency-Modulated (LFM) signals corrupted in complex-valued zero-mean Multiplicative Noise (MN), and (ii) the Underdetermined Blind Source Separation (UBSS) of LFM signals, while focusing onto the fast-growing area of Wireless Communications (WCom).A common problem in the issue of signal estimation is the estimation of the frequency of Frequency-Modulated signals which are seen in many engineering and real-life applications. Accurate frequency estimation leads to accurate recovery of the true information. In some applications, the random amplitude modulationshows up when the medium is dispersive and/or when the assumption of point target is not valid; the original signal is considered to be corrupted by an MN process thus seriously aecting the recovery of the information-bearing frequency. The IF estimation of nonstationary signals corrupted by complex-valued zero-mean MNwas investigated in this research. We have proposed a Second-Order Statistics approach,rather than a Higher-Order Statistics approach, for IF estimation using Time-Frequency Distributions (TFDs). The main assumption was that the autocorrelation function of the MN is real-valued but not necessarily positive (i.e. the spectrum of the MN is symmetric but does not necessary has the highest peak at zero frequency). The estimation performance was analyzed in terms of bias and variance, and compared between four dierent TFDs: Wigner-Ville Distribution, Spectrogram, Choi-Williams Distribution and Modified B Distribution. To further improve the estimation, we proposed to use the Multiple Signal Classification algorithmand showed its better performance. It was shown that the Modified B Distribution performance was the best for Signal-to-Noise Ratio less than 10dB.In the issue of signal separation, a new research direction called Blind Source Separation (BSS) has emerged over the last decade. BSS is a fundamental technique in array signal processing aiming at recovering unobserved signals or sources from observed mixtures exploiting only the assumption of mutual independence between the signals. The term indicates that neither the structure of the mixtures nor the source signals are known to the receivers. Applications of BSS are seen in, for example, radar and sonar, communications, speech processing, biomedical signal processing. In the case of nonstationary signals, a TF structure forcingapproach was introduced by Belouchrani and Amin by defining the Spatial Time- Frequency Distribution (STFD), which combines both TF diversity and spatial diversity. The benefit of STFD in an environment of nonstationary signals is the direct exploitation of the information brought by the nonstationarity of the signals.A drawback of most BSS algorithms is that they fail to separate sources in situations where there are more sources than sensors, referred to as UBSS. The UBSS of nonstationary signals was investigated in this research. We have presented a new approach for blind separation of nonstationary sources using their TFDs. Theseparation algorithm is based on a vector clustering procedure that estimates thesource TFDs by grouping together the TF points corresponding to closely spacedspatial directions. Simulations illustrate the performances of the proposed method for the underdetermined blind separation of FM signals. The method developed in this research represents a new research direction for solving the UBSS problem.The successful results obtained in the research development of the above two problems has led to a conclusion that TFSP is useful for WCom. Future research directions were also proposed." @default.
• W12192253 created "2016-06-24" @default.
• W12192253 creator A5069979656 @default.
• W12192253 date "2004-01-01" @default.
• W12192253 modified "2023-09-28" @default.
• W12192253 title "Estimation and separation of linear frequency- modulated signals in wireless communications using time - frequency signal processing." @default.
• W12192253 cites W118655728 @default.
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• W12192253 cites W1500551892 @default.
• W12192253 cites W1508050876 @default.
• W12192253 cites W1510095622 @default.
• W12192253 cites W1516996557 @default.
• W12192253 cites W1540597053 @default.
• W12192253 cites W1541552825 @default.
• W12192253 cites W1560984276 @default.
• W12192253 cites W1572210620 @default.
• W12192253 cites W1577259078 @default.
• W12192253 cites W1577900252 @default.
• W12192253 cites W1588837646 @default.
• W12192253 cites W1596939795 @default.
• W12192253 cites W1601759414 @default.
• W12192253 cites W1615529464 @default.
• W12192253 cites W1634005169 @default.
• W12192253 cites W1652326934 @default.
• W12192253 cites W1901998444 @default.
• W12192253 cites W1958563038 @default.
• W12192253 cites W1965392255 @default.
• W12192253 cites W1971527405 @default.
• W12192253 cites W1983592970 @default.
• W12192253 cites W1994475615 @default.
• W12192253 cites W1995493818 @default.
• W12192253 cites W1998735357 @default.
• W12192253 cites W2023930512 @default.
• W12192253 cites W2027393753 @default.
• W12192253 cites W2038237443 @default.
• W12192253 cites W2077783632 @default.
• W12192253 cites W2080823928 @default.
• W12192253 cites W2083407651 @default.
• W12192253 cites W2088881802 @default.
• W12192253 cites W2090705694 @default.
• W12192253 cites W2092493154 @default.
• W12192253 cites W2094413642 @default.
• W12192253 cites W2096710051 @default.
• W12192253 cites W2099465098 @default.
• W12192253 cites W2099741732 @default.
• W12192253 cites W2100115174 @default.
• W12192253 cites W2100786243 @default.
• W12192253 cites W2102382015 @default.
• W12192253 cites W2112018306 @default.
• W12192253 cites W2114509411 @default.
• W12192253 cites W2119582085 @default.
• W12192253 cites W2119647652 @default.
• W12192253 cites W2124541664 @default.
• W12192253 cites W2128386125 @default.
• W12192253 cites W2128582577 @default.
• W12192253 cites W2130917709 @default.
• W12192253 cites W2131730561 @default.
• W12192253 cites W2132085292 @default.
• W12192253 cites W2134631245 @default.
• W12192253 cites W2135836178 @default.
• W12192253 cites W2138139842 @default.
• W12192253 cites W2141180073 @default.
• W12192253 cites W2142969214 @default.
• W12192253 cites W2144572173 @default.
• W12192253 cites W2144897252 @default.
• W12192253 cites W2145417574 @default.
• W12192253 cites W2146635429 @default.
• W12192253 cites W2154068615 @default.
• W12192253 cites W2154618652 @default.
• W12192253 cites W2158456262 @default.
• W12192253 cites W2159667016 @default.
• W12192253 cites W2161219071 @default.
• W12192253 cites W2163288559 @default.
• W12192253 cites W2164549078 @default.
• W12192253 cites W2166159048 @default.
• W12192253 cites W2168061989 @default.
• W12192253 cites W2169791062 @default.
• W12192253 cites W2170885247 @default.
• W12192253 cites W2171537808 @default.
• W12192253 cites W2225904595 @default.
• W12192253 cites W249352492 @default.
• W12192253 cites W2612977707 @default.
• W12192253 cites W2798333393 @default.
• W12192253 cites W2798909945 @default.
• W12192253 cites W2976640307 @default.
• W12192253 cites W3151807103 @default.
• W12192253 cites W3216068995 @default.
• W12192253 cites W49913121 @default.
• W12192253 cites W612406868 @default.
• W12192253 cites W623552506 @default.
• W12192253 cites W641242542 @default.
• W12192253 cites W92250306 @default.
• W12192253 hasPublicationYear "2004" @default.
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