design, simulation and optimal selection of cosine-linear frequency modulation waveform (cnlfm) based on correlated ambiguity function (af) method for the purpose of synthetic aperture radar (sar) is done in this article. the selected optimum cnlfm waveform in contribution with other waveforms are applied directly into a sar image formation algorithm (ifa) and their quality effects performance ...

In this paper, we proposed a method for radar modulation identification using power inequality in frequency domain. The four classes of radar signals are classified: unmodulated (UM), linear frequency modulation (LFM), non-linear frequency modulation (NLFM), and frequency shift keying (FSK). To measure the frequency inequality, Gini's coefficient was introduced and the maximum likelihood (ML) c...

A Design, simulation and optimal selection of non-linear frequency modulation waveforms (NLFM) based on correlated ambiguity function (AF) quality analysis for the purpose of Synthetic Aperture Radar (SAR) is done in this article. The selected optimum CNLFM waveform in contribution with other waveforms are applied directly into a SAR image formation algorithm (IFA) and their quality metrics in ...

—The characteristics typical S-shaped Nonlinear Frequency Modulation (S-NLFM) signal are analyzed, and a detection method for this type of signal is also proposed. First of all, the instantaneous frequency of the S-NLFM signal based on sinusoid modulation and tangent modulation is obtained by phase unwrapping respectively. Then, two characteristics are obtained from instantaneous frequency. Co...

Abstract The Nonlinear Frequency Modulation (NLFM) signals have been gradually used in new radar systems, however its instantaneous frequency (IF) estimation is still a difficult problem. This paper introduces the generalized S-transform to NLFM signals processing fields and proposes a new IF estimation algorithm of NLFM signals in low SNR based on generalized S-transform. Firstly, the timefreq...

The radome can protect the enclosed antenna from harsh weather and environmental conditions; however, it will cause a non-negligible effect particularly transmission loss on wideband signal which has been widely used in electronic systems. For this, novel compensation method for based non-linear frequency modulation (NLFM) waveform design is proposed. First, coefficient calculation process give...

It is well known that in the pulse compression radar theory, the sidelobe reduction using nonlinear frequency modulation (NLFM) signal processing represents a major and present research direction. Accordingly, the main objective of this paper is to propose an interesting approach related to the design of efficient NLFM waveforms namely, a temporal predistortioning method of LFM signals by suita...

Since the advent of “pulse compression” radar, the “chirp” signal (Linear Frequency Modulation, LFM) has been one of the most widely used radar waveforms. It is well known that, by changing its modulation into a Non-Linear Frequency Modulation (NLFM), better performance in terms of Peak-to-Sidelobes Ratio (PSLR) can be achieved to mitigate the masking effect of nearby targets and to increase th...

Abstract The non-linear frequency modulation (NLFM) waveform is one of the existing waveforms that can be used in high range resolution radar applications. However, a sampling and consequently an expensive ADC are required. To overcome this drawback while taking advantage features NLFM waveform, we suggest approximating wideband by piecewise linear using it stepped (SF) framework. Thus, variabl...