Families of pseudorandom sequences with low cross correlation have important applications in communications and cryptography. Among several known constructions of sequences with low cross correlations, interleaved constructions proposed by Gong uses two sequences of the same period with two-level autocorrelation. In this paper, we study the balance property and the cross correlation of interlea...

We develop a method for estimating the shear power spectra from weak lensing observations and test it on simulated data. Our method describes the shear field in terms of angular power spectra and cross correlation of the two shear modes which differ under parity transformations. Two of the three power spectra can be used to monitor unknown sources of noise in the data. The power spectra are dec...

We report on a programme to monitor the radial velocities of a sample of candidate and confirmed carbon-enhanced, metal-poor (CEMP) stars. We observed 45 targets using the Echelle Spectrographs of three 4-m class telescopes. Radial velocities for these objects were calculated by cross-correlation of their spectra with the spectrum of HD 140283, and have errors < 1 km s−1. Sixteen of our program...

For a fast moving CROSS-AMBIGUITY FUNCTION Kam W. Lo and Brian G. Ferguson Defence Science and Technology Organisation P.O. Box 44 Pyrmont NSW Australia acoustic source in proximity to a pair of widely spaced sensors, the conventional cross correlation method results in poor time delay estimates because the signal received by each sensor experiences a different degree of time scaling. The corre...

Soil heterogeneity and the lack of detailed site characterization are two ubiquitous factors that render predictions of flow and transport in the vadose zone inherently uncertain. We employ the Green–Ampt model of infiltration and the Dagan– Bresler statistical parameterization of soil properties to compute probability density functions (PDFs) of infiltration rate and infiltration depth. By goi...

Timely traffic prediction is important in advanced traffic management systems. Observing traffic flow, we find repetitive or regular behavior over time. By taking advantage of tools in frequency domain analysis, this paper proposes a new criterion function that can detect the onset of congestion. It is found that the changing rate of the cross-correlation between density dynamics and flow rate ...

Let p be an odd prime and n = 2m with p ≡ 1 (mod 4). In this paper, the cross-correlation distribution between two decimated sequences of a p-ary m-sequence, s(2t+ i) with i ∈ {0, 1} and s(d′t) with d′ = 2d, d = ( p +1 2 ) is determined.

The present paper proposes two methods for constructing new asymmetric ZCZ sequence sets. ZCZ sequence sets are used as spreading sequences for AS-CDMA systems. An asymmetric ZCZ sequence set is a type of ZCZ sequence set and consists of multiple sequence subsets. Compared with conventional ZCZ sequence sets, the most important property of the proposed asymmetric ZCZ sequence sets is that the c...

Since its launch on October 2002 the INTEGRAL satellite is performing an deep survey of the hard X–ray sky with unprecedented sensitivity and positional accuracy. This allowed pinpointing, through positional cross-correlation with catalogs at longer wavelengths, possible optical/near-infrared candidates for the hard X–ray sources of still unknown nature. In this presentation I will describe thi...

Several results have been reported in the literature on the performance of various diversity combining schemes for wireless communications systems. Typically for convenience it is assumed that the signal envelopes in the diversity branches are uncorrelated with one another. However, in practice the envelopes will be correlated. In this paper a procedure to generate two equal power Rayleigh fadi...