Fractal box dimension as a feature is widely used in many fields such as spectrum sensing in cognitive radio, image processing, modulation recognition of signals, parameter estimation of signals, and so on. In order to improve the estimation accuracy of it, an improved feature extraction method of modulation signal is proposed under low signal-to-noise ratio(SNR). In the absence of a priori kno...

This paper deals with the Dual-Function Radar and Communication (DFRC) signal design for a Multiple-Input–Multiple-Output (MIMO) system, considering presence of signal-dependent clutter. A modulation methodology called Spectral Position Index Amplitude (SPIA) is proposed, which involves selecting passband stopband positions applying amplitude modulation. Signal to Interference plus Noise Ratio ...

Extending an existing architecture for delta-sigma conversion of vector inputs, we suggest spectrally shaping quantization noise jointly in temporal and spatial frequency domains with delta-sigma modulation, and we examine the application of the idea to wideband antenna or acoustic arrays and to halftoning of video imagery.

In this paper we present a method for stability analysis of high order Sigma-Delta modulators. The method is based on a parallel decomposition of the modulator. Using this presentation the general N-th order modulator could be considered as made up of N first order modulators, which interact only through the quantizer function. The decomposition helps us to extract the stability conditions of t...

The automatic recognition of the modulation format of a detected signal, the intermediate step between signal detection and demodulation, is a major task of an intelligent receiver, with various civilian and military applications. Obviously, with no knowledge of the transmitted data and many unknown parameters at the receiver, such as the signal power, carrier frequency and phase offsets, timin...

Modulation type is one of the most important characteristics used in signal recognition. An algorithm to realize signal modulation identification is proposed in this paper. We applied wavelet transformation and STFT to the signal, and then used manifold learning method to reduce the high dimension and extracted the recognition feature. The proper threshold value was set as the classifier to ach...

An automatic method for classifying frequency shift keying (FSK), minimum (MSK), phase (PSK), quadrature amplitude modulation (QAM), and orthogonal division multiplexing (OFDM) is proposed by simultaneously using normality test, spectral analysis, geometrical characteristics of in-phase-quadrature (I-Q) constellation diagram. Since the extracted features are unique each modulation, they can be ...

This paper deals with mechanical fault diagnosis in three-phase induction machines from stator current measurements. According to machine models, mechanical faults lead to amplitude and/or phase modulations of the measured stator current with possibly time varying carrier frequency. The modulation diagnosis requires a univocal definition of the instantaneous phase and amplitude. This is perform...

The automatic recognition of the modulation format of a detected signal, the intermediate step between signal detection and demodulation, is a major task of an intelligent receiver, with various civilian and military applications. Obviously, with no knowledge of the transmitted data and many unknown parameters at the receiver, such as the signal power, carrier frequency and phase offsets, timin...

where ∆k = ki+ks−2kp is the phase mismatch calculated from weak-signal dispersion of the transmission line. The term on the right hand side of the pump equation represents the selfphase modulation due to the AC pump current interacting with itself. Analogous cross-phase modulation processes are represented by the rst term on the right hand side of the signal and idler equations; the other term ...