one of the most common signals used for achieving high range resolution in radar is stepped-frequency signals. when a target is stationary in these radars, dft (discrete fourier transform) based processing is used to attain high range resolution profile (hrrp). however, in the case of moving target, due to spreading of the echo signal spectrum, dft based processing is not optimal and decreases ...

We consider a common problem in physics: How to estimate a smooth function given noisy measurements. We assume that the unknown signal is measured at N different times, {ti: i = 1, . . . N} and that the measurements, {yi}, have been contaminated by additive noise. Thus the measurements satisfy yi = g(ti) + i, where g(t) is the unknown signal and i are random errors. For simplicity, we assume th...

The discrete Fourier transform (DFT) has found tremendous applications in almost all fields, mainly because it can be used to match the multiple frequencies of a stationary signal with multiple harmonics. In many applications, wideband and nonstationary signals, however, often occur. One of the typical examples of such signals is chirp-type signals that are usually encountered in radar signal p...

In this paper, the reassigned local polynomial periodogram along the frequency direction (RfLPP) is shown to be able to perfectly localize the chirp signal. Due to this property, the RfLPP is combined with the Hough transform for chirp signal detection in the parameter domain. Simulations of the RfLPP-Hough transform are given for chirp signal detection in white Gaussian noise and impulsive noi...

In this paper, we present a robust timing offset estimation method using subautocorrelation functions for uniand bi-directional chirp signals. The presented timing offset estimator is designed to be applied with a generalized chirp signal sequence, which use unior bi-directional chirp symbols. Using the conjugate property of the chirp signal, the sub-autocorrelation functions are generated to b...

The target echo of downward-looking radar can be simulated by a multicomponent Chirp signal with noise, which makes signal detection and parameter estimation a very important processing. Aiming at the problems of error detection caused by the cross-terms in WVDHough methods and other modified WVD distribution methods, and low precision due to poor time-frequency concentration in S-Hough transfo...

An inspection of signal processing approach in order to estimate underwater network cardinalities is conducted in this research. A matter of key prominence for underwater network is its cardinality estimation as the number of active cardinalities varies several times due to numerous natural and artificial reasons due to harsh underwater circumstances. So, a proper estimation technique is mandat...

A low data-rate communication technique using linear step frequency modulated (LSFM) signal is presented. When the carrier frequency offset (CFO) between the transmitter and the receiver is significant comparing to the symbol rate, the techniques using normal signaling waveforms with matched filtering become infeasible. In this scenario, wideband chirp (linear FM) signal is feasible because of ...