Phase from Zero-Crossings
نویسنده
چکیده
The theory of zero-crossing detection is extended to include the first and second spatial derivative of the gaussian distribution. On the premise that phase contains a considerable proportion of the information content in an unknown signal, we show that phase can be extracted from the first and second derivatives of an appropriate filter. It is shown that the spatial gradient of phase can be used to obtain an estimate for the local spectral properties of a signal. By assigning an upper and lower frequency cut-off to each filter, it is suggested that false zero-crossings can be removed from analysis. by the complex form:
منابع مشابه
A Phase Noise Reduction Technique in LC Cross-coupled Oscillators with Adjusting Transistors Operating Regions
In this paper, an intuitive analysis of a phase noise reduction technique is done, and then a modified structure is proposed to achieve higher phase noise reduction than the original one. This method reduces the impact of noise sources on the phase noise by decreasing closed-loop gain in zero-crossings points and moving this high closed-loop gain to the non-zero-crossings points. This reduction...
متن کاملReconstruction of Two-dimensional Signals from Threshold Crossings *
In this paper, we present new results on the reconstruction of two-dimensional signals from zero crossing or threshold crossing information. These results follow from our previous work on the reconstruction of twodimensional signals from one bit of Fourier transform phase. Experimental results illustrating image reconstruction from threshold crossings are included.
متن کاملOn representing signals using only timing information.
It is well known that only a special class of bandpass signals, called real-zero (RZ) signals can be uniquely represented (up to a scale factor) by their zero crossings, i.e., the time instants at which the signals change their sign. However, it is possible to invertibly map arbitrary bandpass signals into RZ signals, thereby, implicitly represent the bandpass signal using the mapped RZ signal'...
متن کاملPhase Based Image Reconstruction in the Monogenic Scale Space
In this paper, we present an approach for image reconstruction from local phase vectors in the monogenic scale space. The local phase vector contains not only the local phase but also the local orientation of the original signal, which enables the simultaneous estimation of the structural and geometric information. Consequently, the local phase vector preserves a lot of important information of...
متن کاملHermite polynomials for signal reconstruction from zero-crossings. 1. One-dimensional signals - Communications, Speech and Vision, IEE Proceedings I
Generalised Hermite polynomials are employed for the reconstruction of an unknown signal from a knowledge of its zero-crossings, under certain conditions on its spatial/spectral width, but dispensing with the assumption of bandlimitedness. A computational implementation of the proposed method is given for one-variable (or one-dimensional) signals, featuring an application of simulated annealing...
متن کامل