Journal of Systems Engineering and Electronics ›› 2018, Vol. 29 ›› Issue (2): 278-285.doi: 10.21629/JSEE.2018.02.08

• Defence Electronics Technology • Previous Articles     Next Articles

ISAR imaging based on improved phase retrieval algorithm

Hongyin SHI*(), Saixue XIA(), Ye TIAN()   

  • Received:2016-12-23 Online:2018-04-26 Published:2018-04-27
  • Contact: Hongyin SHI E-mail:shihy@ysu.edu.cn;945302090@qq.com;tianye@ysu.edu.cn
  • About author:SHI Hongyin was born in 1976. He received his Ph.D. degree from Beihang University in 2009. Now, he is a professor in Yanshan University. His main research interests include SAR imaging and moving target detection. E-mail: shihy@ysu.edu.cn|XIA Saixue was born in 1990. She received her bachelor degree from Yanshan University in 2010. Now, she is a master student in School of Information and Engineering, Yanshan University. She is mainly engaged in the research of phase retrieval and the ISAR imaging. E-mail: 945302090@qq.com|TIAN Ye was born in 1986. He received his Ph.D degree in communication engineering from Jilin University in 2014. Now he is an associate professor in Yanshan University. His main research interests include direction-of-arrival estimation, sparse signal reconstruction and phase retrieval. E-mail: tianye@ysu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(61571388);the National Natural Science Foundation of China(61601398);the National Natural Science Foundation of Hebei Province(F2016203251);This work was supported by the National Natural Science Foundation of China (61571388; 61601398) and the National Natural Science Foundation of Hebei Province (F2016203251)

Abstract:

Traditional inverse synthetic aperture radar (ISAR) imaging methods for maneuvering targets have low resolution and poor capability of noise suppression. An ISAR imaging method of maneuvering targets based on phase retrieval is proposed, which can provide a high-resolution and focused map of the spatial distribution of scatterers on the target. According to theoretical derivation, the modulus of raw data from the maneuvering target is not affected by radial motion components for ISAR imaging system, so the phase retrieval algorithm can be used for ISAR imaging problems. However, the traditional phase retrieval algorithm will be not applicable to ISAR imaging under the condition of random noise. To solve this problem, an algorithm is put forward based on the range Doppler (RD) algorithm and oversampling smoothness (OSS) phase retrieval algorithm. The algorithm captures the target information in order to reduce the influence of the random phase on ISAR echoes, and then applies OSS for focusing imaging based on prior information of the RD algorithm. The simulated results demonstrate the validity of this algorithm, which cannot only obtain high resolution imaging for high speed maneuvering targets under the condition of random noise, but also substantially improve the success rate of the phase retrieval algorithm.

Key words: inverse synthetic aperture radar (ISAR), maneuvering target, autofocus imaging, phase retrieval, oversampling smoothness (OSS)