Time-frequency representations of generalized almost-cyclostationary sig
نویسندگان
چکیده
Nous proposons dans cet article une contribution à la théorie récemment introduite des signaux quasi-cyclostationnaires généralisés. Cette classe de signaux étend la classe des signaux quasicyclostationnaires au cas de signaux dont les fréquences cycliques dépendent du temps. Des représentations temps-fréquence de ces signaux sont données en fonction des statistiques cycliques généralisées. Notamment, la distribution de Wigner-Ville et la fonction d’ambiguité sont examinées en détail. Le problème de l’extraction des caractéristiques des signaux quasi-cyclostationnaires généralisés, basée sur l’estimation d’un seul enregistrement, est également traité. ABSTRACT
منابع مشابه
Some Results on the Wavelet Packet Decomposition of Nonstationary Processes
Wavelet/wavelet packet decomposition has become a very useful tool in describing nonstationary processes. Important examples of nonstationary processes encountered in practice are cyclostationary processes or almost-cyclostationary processes. In this paper, we study the statistical properties of the wavelet packet decomposition of a large class of nonstationary processes, including in particula...
متن کاملParamorphic multicarrier communications for interference mitigation
This paper presents a novel method for enabling communication in cyclostationary interference limited environments by adaptively inserting and exploiting spectral redundancy in an orthogonal frequency division multiplexing (OFDM) signal. The redundancy is formed through repeating data symbols across OFDM symbols in both time and frequency. A novel frequency shift (FRESH) filter is applied to ex...
متن کاملGeneralized Wideband Cyclic MUSIC
The method of Spectral Correlation-Signal Subspace Fitting (SC-SSF) fails to separate wideband cyclostationary signals with coherent second-order cyclic statistics (SOCS). Averaged Cyclic MUSIC (ACM) method made up for the drawback to some degree via temporally averaging the cyclic cross-correlation of the array output. This paper interprets ACM from another perspective and proposes a new DOA e...
متن کاملASYMPTOTIC NORMALITY OF STATISTICAL−FUNCTION ESTIMATORS FOR GENERALIZED ALMOST−CYCLOSTATIONARY PROCESSES (ThuAmOR7)
The problem of estimating second−order statistical functions of generalized almost−cyclostationary (GACS) processes is addressed. The class of such nonstationary processes includes, as a special case, the almost−cyclostationary (ACS) processes. ACS processes filtered by Doppler channels and communications signals with time−varying parameters are further examples. It is shown that, for GACS proc...
متن کاملNon-Data-Aided Feedforward Carrier Frequency Offset Estimators for QAM Constellations: A Nonlinear Least-Squares Approach
This paper performs a comprehensive performance analysis of a family of non-data-aided feedforward carrier frequency offset estimators for QAM signals transmitted through AWGN channels in the presence of unknown timing error. The proposed carrier frequency offset estimators are asymptotically (large sample) nonlinear least-squares estimators obtained by exploiting the fourthorder conjugate cycl...
متن کامل