An autocorrelation measurement of femtosecond laser pulse duration using the Kerr-lens mechanism is demonstrated. This technique can also be used as a sensitive and absolutely calibratable method for measuring ultrafast optical nonlinearities. A method that uses an electronic spectral-filtering scheme is proposed for determining the frequency chirp of pulses by interferometric autocorrelation.

This paper presents an efficient and homogeneous paradigm for automatic acquisition and recognition of nonparametric shapes. Acquisition time varies from linear to cubic in the number of object features. Recognition time is linear to cubic in the number of features in the image and grows slowly with the number of stored models. Nonparametric shape representation is achieved by spatial autocorre...

EXt = μ Cov(Xt, Xt−k) = γk (lag-k autocovariance). The lag zero autocovariance γ0 is just the variance of the time series. γk’s are of central importance in time series analysis as they characterize the serial dependence over observations (i.e. over time). We usually do not have iid data in time series contexts. A white noise series is stationary. A white noise (WN) series is defined as an unco...

Judgmental detection of changes in time series is an ubiquitous task. Previous research has shown that human observers are often relatively poor at detecting change, especially when the series are serially dependent (autocorrelated). We present two experiments in which participants were asked to judge the occurrence of changes in time series with varying levels of autocorrelation. Results show ...

We derive a recursion relation for the frequency autocorrelation function of the polarization dispersion vector for polarization mode dispersion emulators with rotators. The autocorrelation function has a nonzero background for an emulator with a fixed number of sections. This background diminishes slowly as the number of sections grows. Randomizing the section lengths removes the autocorrelati...

Stochastic waveforms are constructed whose expected autocorrelation can be made arbitrarily small outside the origin. These waveforms are unimodular and complex-valued. Waveforms with such spike like autocorrelation are desirable in waveform design and are particularly useful in areas of radar and communications. Both discrete and continuous waveforms with low expected autocorrelation are const...

The cyclic autocorrelation of common digital modulation is researched, and the relationship between the cyclic autocorrelation and the delay, corresponding to the symbol rate, is deduced, then a searching algorithm for the symbol rate is proposed. Theoretical analyses and simulation results show that this method has less computation complexity and is also quite accurate. The estimation result i...

In this paper, for a prime p and a positive integer q such that q|pn − 1, we constructed q-ary Lempel– Cohn–Eastman(LCE) sequences with period p − 1. These sequences have maximum autocorrelation magnitude bounded by 4. Particularly, in the case of q = 3, the maximum autocorrelation magnitude of the ternary LCE sequences is 3. And the maximum autocorrelation magnitude of the quaternary LCE seque...

The autocorrelation function and the run structure are two basic notions for binary sequences, and they have been used as two independent criterions to characterize the randomness of binary sequences for more than 30 years. In this paper, we establish a run series expansion formula for autocorrelation function of the binary sequence and show that the autocorrelation function is in fact complete...

this paper  considersthe problem of  aliasing in information processing. the cubic spline method of interpolating the uniformly sampled signals and its effects on the autocorrelation estimation as well as the resulting spectral density function are studied by simulating random signals with known autocorrelation functions. hence, by comparison of aliased and alias-free cases, indications are ded...