导航

ACTA AERONAUTICAET ASTRONAUTICA SINICA ›› 2022, Vol. 43 ›› Issue (S2): 67-75.doi: 10.7527/S1000-6893.2022.27715

Previous Articles     Next Articles

Long-term energy focusing method for target covered by plasma sheath

Tingkun ZHANG1(), Zheng LI2, Xudong WEN3, Yiqing HONG1, Bowen BAI1   

  1. 1.School of Aerospace Science and Technology,Xidian University,Xi’an 710126,China
    2.Beijing Institute of Adjacent Space Vehicle Systems Engineering,Beijing 100076,China
    3.Unit 63601 of the PLA,Korla 841000,China
  • Received:2022-06-30 Revised:2022-08-22 Accepted:2022-09-13 Online:2022-12-25 Published:2022-09-30
  • Contact: Tingkun ZHANG E-mail:20131213338@stu.xidian.edu.cn
  • Supported by:
    National Natural Science Foundation of China(62171349);Shaanxi Natural Science Basic Research Program(2020JM-102)

Abstract:

As the reentry object travels at hypersonic speeds, its surface is covered by a plasma sheath. The plasma sheath modulates the radar echo in amplitude, phase and frequency, which seriously affects the reliable detection capability of the radar for re-entry targets and results in various abnormal radar detection problems. In this paper, the influence of the plasma sheath on the radar echo is analyzed by establishing a radar echo model for the target covered by the plasma sheath. A Doppler frequency cancellation method based on slow time autocorrelation is proposed, which can effectively solve the multi-Doppler frequency phenomenon in the radar echo caused by the non-uniform plasma sheath. The extended Keystone transform and the inverse Fourier transform are used to decouple the coupling terms in the correlated signal, thereby realizing energy focusing of the signal. The validity of the algorithm proposed is verified by the simulation analysis of the multi-period echo signal, and the reliability of the algorithm is verified by statistical experimental analysis. This study provides an effective method for the coherent accumulation of the plasma sheath covered target.

Key words: plasma sheath, radar echo, intra-pulse Doppler frequency, slow time autocorrelation, coherent accumulation

CLC Number: