Modified PWNLFM Signal for Side-Lobe Reduction

  • Authors

    • N. Adithya valli
    • Dr. D. Elizabath Rani
    2018-11-28
    https://doi.org/10.14419/ijet.v7i4.20.22110
  • ACF, LFM, NLFM, PSLR, PWNLFM.

  • Many applications in radar systems require low range side-lobe performance which is achieved by pulse compression processing. Most used chirp signal for this processing is linear frequency modulation (LFM) signal but with a presence of first high side-lobe level. Suppression of this side-lobe requires weighting function causing the reduction in signal to noise ratio at the receiver owing to mismatch loss. Non-linear chirp signals are introduced as a solution and became most practiced signals aimed at reducing side-lobes. In this paper, an overall piece wise non-linear frequency modulation chirp signal is designed by merging two stages, one with linear function and the other with a tangent based non-linear function. Simulation results show significant reduction in the sidelobe level of autocorrelation function when NLFM is generated in this method.

     

  • References

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  • How to Cite

    Adithya valli, N., & D. Elizabath Rani, D. (2018). Modified PWNLFM Signal for Side-Lobe Reduction. International Journal of Engineering & Technology, 7(4.20), 4-7. https://doi.org/10.14419/ijet.v7i4.20.22110