The synthesis of a radar signal having nonlinear frequency modulation function

Abstract

A method of signal synthesis is presented. After theoretical introduction an algorithm of frequency modulated (FM) signal synthesis is presented. Simulation results made in Matlab are presented in the last chapter.

Sidelobes Reduction Using Synthesis of Some NLFM Laws

“…Having as starting point the experimental results reported in [13][14][15], it seems that some very good results have been obtained in case of Taylor and Blackman-Harris weighting windows as sidelobes reduction techniques, and therefore, these two types of PSD functions will be next used for synthesis and comparative analysis of the matched NLFM laws by the above described algorithm.…”

“…Consequently, having as starting point a signal with rectangular envelope and phase modulation law given by (13), the absolute of the estimated spectral density function assigned to this signal S es (jω) can be easily calculated using the left equation from (1). Next, if we try to compare this estimated function with the predefined one from (8) S pd (jω), than the superposition between these two spectra is achieved only in the points where the stationary phase condition is accomplished.…”

“…Referring now at the synthesis of the NLFM laws using the stationary phase principle, in literature several scientific papers containing some interesting results are illustrated [3,4,[12][13][14]. However, as a common design characteristic, all these methods have as starting point the choice of a desired spectrum shape (generally, only ordinary window functions), and gradually perform the calculus of the NLFM waveform, but no details about the structure of the synthesis methods or clear idea about the concrete way to set the parameters involved in this process in order to preserve for example, the target detection/ranging quality as in case of similar basis LFM signal, are indicated.…”

“…However, all these processing methods can be generally divided into two major research directions, namely: a) design and synthesis of pseudo-NLFM (piecewise) waveforms which are in fact, signals with LFM predistortioned on short intervals into temporal domain or corrected into spectral domain [10,11]; b) design and synthesis of proper (i.e., as predefined shape of the energy/power spectral density (E/PSD) function) pure NLFM waveforms using for example, proper iterative methods [3,11], stationary phase principle, [12][13][14][15] or explicit functions cluster method [16] etc. In addition, the most part of the processing methods used to assure a consistent sidelobes reduction belonging to standard computational techniques [6][7][8][9][10][11][12][13][14][15][16], but some interesting aspects connected with AI paradigms are also discussed in literature [17].…”

Sidelobe Reduction in the Pulse-Compression Radar Using Synthesis of NLFM Laws

“…However, all these processing methods can be generally divided into two major research directions, namely: (a) design and synthesis of pseudo-NLFM waveforms which are in fact signals with LFM predistortioned on short intervals into temporal domain or corrected into spectral domain [10][11][12]; (b) design and synthesis of purely (i.e., as predefined shape of the energy/power spectral density (E/PSD) function) NLFM waveforms using, for example, proper iterative methods [3,11], stationary phase principle [13][14][15][16], or explicit functions cluster method [17,18], and so forth. In addition, the most part of the present processing methods used to assure the sidelobe reduction belonging to standard computational techniques [6][7][8][9][10][11][12][13][14][15][16][17][18], but some interesting aspects connected with artificial intelligence paradigms are also discussed in the literature [19][20][21].…”