Optimization of two-stage NLFM signal using Heuristic approach

Chandu Kavitha; Nettem Adithya Valli; Madhavaprasad Dasari

doi:10.17485/IJST/v13i44.1841

Article

Optimization of two-stage NLFM signal using Heuristic approach

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Indian Journal of Science and Technology

DOI: 10.17485/IJST/v13i44.1841

Year: 2020, Volume: 13, Issue: 44, Pages: 4465-4473

Original Article

Optimization of two-stage NLFM signal using Heuristic approach

Chandu Kavitha^1*, Nettem Adithya Valli², Madhavaprasad Dasari¹

¹Department of Electronics and Physics, GITAM Institute of Science, GITAM Deemed to be University, Visakhapatnam, 530045, A.P, India
²Department of Electrical Electronics and Communication Engineering, GITAM Institute of Technology, GITAM deemed to be University, Visakhapatnam, 530045, A.P, India

*Corresponding Author
Email: [email protected]

Received Date:14 October 2020, Accepted Date:03 December 2020, Published Date:10 December 2020

This work is licensed under a Creative Commons Attribution 4.0 International License.

Abstract

Background/Objectives: The design of appropriate Non-Linear Frequency Modulation (NLFM) signals continues to be the focus of research in radar pulse compression theory for sidelobe reduction. This study focuses on a heuristic design and optimization algorithm to optimize the side lobe values of the NLFM signal designed using two-piece wise linear frequency modulation (LFM) functions. Methods: 1) Heuristic search identifies the optimum B1, T1, and B2, T2, which yield the lowest sidelobe value of the designed function.2) Compute all the side lobe values of the designed NLFM signal using an algorithm developed in Python scripting language. To plot a complete contour map for all the calculated side lobe values, which helps identify the associated variations in the range of side lobe values. Finally, optimize the side lobe values keeping the main lobe width and time-bandwidth (BT) product unchanged by designing a dynamic optimization algorithm. Findings: The algorithm developed considered all side lobe levels after the main lobe for optimization. The focus is mainly on the peak sidelobe ratio (PSLR) value without affecting the other parameters. The results demonstrate that the achieved side lobes exhibit their desired levels. Novelty: The method is useful in all types of hardware associated with weather radar applications to military solutions. The technique can be extended to other multistage signals consisting of piecewise linear Segments.

Keywords: Contour; LFM; NLFM; optimization; PSLR

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Copyright

© 2020 Kavitha et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Published By Indian Society for Education and Environment (iSee)