A Coherence Improvement Method Based on Sub-Aperture InSAR for Human Activity Detection

Zhongbin Wang,Bingnan Wang,Xiaoning Hu,Chong Song,Yachao Wang,Shuai Wang,Maosheng Xiang

doi:10.3390/s21041424

Abstract

Human activity detection plays an important role in social security monitoring. Since human activity is very weak, it is necessary to employ the repeat-pass Interferometric Synthetic Aperture Radar (InSAR) technique to detect the potential activity between two data acquisitions; a high level of coherence is required for detection. With the object of detecting human activity of interest, this paper presents a coherence improvement approach based on sub-aperture InSAR for human activity detection. Different sub-apertures contain different scattering information of the target, as they represent the backscatter of the target from a different range of angles. Integrating corresponding sub-aperture interferometric results can improve the coherence between two complex images compared to the entire synthetic aperture, as well as removing a little disturbance in some circumstances. To validate the method presented in this paper, the actual airborne Ka-band frequency modulated continuous wave (FMCW) InSAR data acquired by the Aerospace Information Research Institute, Chinese Academy of Sciences (AIRCAS) are utilized. The experimental results demonstrate that the proposed method can effectively improve the coherence between two complex SAR images and can validly detect human activity of interest.

Highlights

SAR is a coherent imaging system that can work all day and in all kinds of weather.It can acquire the temporal images of an area conveniently
The actual airborne data collected by the Ka-band frequency modulated continuous wave (FMCW) Interferometric Synthetic Aperture Radar (InSAR) system of the Aerospace Information Research Institute, Chinese Academy of Sciences were used to verify the performance of the method proposed in this paper
In order to verify the performance of the method in this paper, a large number of experiments were performed with actual airborne InSAR data, and a set of data was selected to illustrate the effectiveness of the method in this paper

Summary

Introduction

SAR is a coherent imaging system that can work all day and in all kinds of weather. It can acquire the temporal images of an area conveniently. With the development of society, security defense, ground search and surveillance [4], threat activity detection on the ground [5], ground activity management and other human activities are becoming important topics of social security [6]. These human activities on the ground can be identified with SAR. In military applications, the need to manage military sites and detect artificial targets in various climatic environments is growing [7]

Methods

Results

Conclusion