Evaluation of Imaging Performance for Sub-Y-type Interferometric Synthetic Aperture Radiometer

PIERS Online ◽  
2005 ◽  
Vol 1 (5) ◽  
pp. 543-546
Author(s):  
Ho-Jin Lee ◽  
Hyuk Park ◽  
Sung-Hyun Kim ◽  
Yong-Hoon Kim
Sensors ◽  
2019 ◽  
Vol 19 (22) ◽  
pp. 5052
Author(s):  
Tan ◽  
Zhang ◽  
Yang ◽  
Sun

In this paper, we introduce a novel sub-bottom profiler, making good use of the Mills cross configuration of multibeam sonar and synthetic aperture techniques of the synthetic aperture sonar system. The receiver array is mounted along the ship keel, while the transmitter array is mounted perpendicular to the receiver array. With the synthetic aperture technique, the along-track resolution can be greatly improved. The system often suffers from motion error, which severely degrades the imaging performance. To solve this problem, the imaging algorithm with motion compensation (MC) is proposed. With the presented method, the motion error is first estimated based on overlapped elements between successive pulses. Then, the echo data is processed by using the range migration algorithm based on the phase center approximation (PCA) method, which simultaneously performs the MC with the estimated motion error. In order to validate the proposed sub-bottom profiler and data processing method, some simulations and lake trial results are discussed. The processing results of the real data further indicate that the presented configuration has great potential to find buried objects in seabed sediments.


2020 ◽  
Vol 96 ◽  
pp. 139-146
Author(s):  
Jinguo Wang ◽  
Zhaozhao Gao ◽  
Jie Gu ◽  
Shiwen Li ◽  
Xiaoyun Zhang ◽  
...  

2014 ◽  
Vol 34 (11) ◽  
pp. 1111001
Author(s):  
魏小峰 Wei Xiaofeng ◽  
耿则勋 Geng Zexun ◽  
曹力 Cao Li ◽  
徐志军 Xu Zhijun

2021 ◽  
Vol 13 (10) ◽  
pp. 1924
Author(s):  
Ha-min Choi ◽  
Hae-sang Yang ◽  
Woo-jae Seong

Synthetic aperture sonar (SAS) is a technique that acquires an underwater image by synthesizing the signal received by the sonar as it moves. By forming a synthetic aperture, the sonar overcomes physical limitations and shows superior resolution when compared with use of a side-scan sonar, which is another technique for obtaining underwater images. Conventional SAS algorithms require a high concentration of sampling in the time and space domains according to Nyquist theory. Because conventional SAS algorithms go through matched filtering, side lobes are generated, resulting in deterioration of imaging performance. To overcome the shortcomings of conventional SAS algorithms, such as the low imaging performance and the requirement for high-level sampling, this paper proposes SAS algorithms applying compressive sensing (CS). SAS imaging algorithms applying CS were formulated for a single sensor and uniform line array and were verified through simulation and experimental data. The simulation showed better resolution than the ω-k algorithms, one of the representative conventional SAS algorithms, with minimal performance degradation by side lobes. The experimental data confirmed that the proposed method is superior and robust with respect to sensor loss.


2017 ◽  
Vol 10 (02) ◽  
pp. 1641004 ◽  
Author(s):  
Qiulan Liu ◽  
Cuifang Kuang ◽  
Yue Fang ◽  
Peng Xiu ◽  
Yicheng Li ◽  
...  

Fourier ptychographic microscopy (FPM) is a newly developed imaging technique which stands out by virtue of its high-resolution and wide FOV. It improves a microscope’s imaging performance beyond the diffraction limit of the employed optical components by illuminating the sample with oblique waves of different incident angles, similar to the concept of synthetic aperture. We propose to use an objective lens with high-NA to generate oblique illuminating waves in FPM. We demonstrate utilizing an objective lens with higher NA to illuminate the sample leads to better resolution by simulations, in which a resolution of 0.28[Formula: see text][Formula: see text]m is achieved by using a high-NA illuminating objective lens (NA[Formula: see text][Formula: see text]) and a low-NA collecting objective lens (NA[Formula: see text][Formula: see text]) in coherent imaging ([Formula: see text][Formula: see text]nm). We then deeply study FPM’s exact relevance of convergence speed to spatial spectrum overlap in frequency domain. The simulation results show that an overlap of about 60% is the optimal choice to acquire a high-quality recovery (520*520 pixels) with about 2 min’s computing time. In addition, we testify the robustness of the algorithm of FPM to additive noises and its suitability for phase objects, which further proves FPM’s potential application in biomedical imaging.


Sign in / Sign up

Export Citation Format

Share Document