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IJSTR >> Volume 8 - Issue 11, November 2019 Edition

International Journal of Scientific & Technology Research  
International Journal of Scientific & Technology Research

Website: http://www.ijstr.org

ISSN 2277-8616

Doppler Effect Analysis Of NLFM Signals

[Full Text]



Adithya Valli Nettem, Elizabath Rani Daniel, Kavitha Chandu



Ambiguity function, Doppler Effect, LFM, Mainlobe Width, NLFM, PSLR.



Waveform design plays a critical role in the current radar technology. Different radar signals can be achieved using tools like ambiguity function and autocorrelation function. Linear Frequency Modulation (LFM) waveform is the most used radar waveform. The main difficulty in LFM is its first high side-lobe level despite of its simple design and Doppler tolerance characteristics. A weighting function is desired to reduce the side-lobe with a penalty of mismatch loss. In an effort, to achieve low auto-correlation side-lobe levels, Non-Linear Frequency Modulation (NLFM) signal has been explored. NLFM has a spectral weighting function inherently in their modulation function which exhibits profoundly reduced side-lobes from its analogues LFM. In this paper, five different NLFM signals are investigated and their performance is assessed based on the study of Doppler Effect, Doppler tolerance and PSLR values. The matlab simulation results were used to decide the most suitable waveform for side lobe reduction.



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