Results 231 to 240 of about 4,257,836 (266)

A Simple Model for Marine Radar Images of the Ocean Surface

IEEE Geoscience and Remote Sensing Letters, 2015
This letter describes a simple model for the backscattered signal received from the ocean surface by a horizontal-polarization marine radar operating at low grazing angles, including the effects of the logarithmic amplifiers conventionally used in these radars. Shadowing is accounted for via geometric optics.
David R. Lyzenga, David T. Walker
openaire   +2 more sources

ISAR imaging with pseudo-coherent marine radars

International Conference on Radar Systems (Radar 2017), 2017
Non-coherent marine radar technology has matured over the past several decades. Researchers have developed coherent magnetron oscillator based marine radars by sampling the signals on transmit and receive [1]. We leverage this research to contribute to the science and technology of RF Tomography based upon exploitation of marine radar technology, and ...
M. Aljohani, H. Abdelbagi, L.L. Monte, A. Mrebit, M.C. Wicks   +4 more
openaire   +1 more source

Navigation by Computer Processing of Marine Radar Images

Journal of Navigation, 1985
The advantages of being able to process marine radar imagery in an on-line computer system have been illustrated by study of some navigational problems. The experiments suggest that accuracies of the order of 100 metres may be obtained in navigation in coastal regions using map overlays with marine radar data.
G. L. Austin, A. Bellon, M. Riley, E. Ballantyne   +3 more
openaire   +1 more source

Marine radar system of systems for radar image quality improvement using EM algorithm

2011 6th International Conference on System of Systems Engineering, 2011
It is important to improve the quality of marine radar images because marine radar systems play a principle role of sea surveillance. However, it is difficult to recover signal strength decay with increasing distance, signals of behind objects and of shaded area.
Hokuto Mita, Syoji Kobashi, Kazuya Nakagawa, Kohji Nishiyama, Hitoshi Maeno, Kei Kuramoto, Yutaka Hata   +6 more
openaire   +2 more sources

A method for feature extraction and classification of marine radar images

2014 World Automation Congress (WAC), 2014
There are ship images (target) and non-ship images (noise) on radar images. In order to obtain other ship information from radar images, it is necessary to select and acquire ship images on radar images. Ship images are selected and acquired by navigation officers based on their observation skill and experience.
Chihiro Nishizaki, Yasuyuki Niwa, Motonobu Imasato, Hisaya Motogi   +3 more
openaire   +1 more source

Ocean surface winds retrieved from marine radar-image sequences

IEEE International IEEE International IEEE International Geoscience and Remote Sensing Symposium, 2004. IGARSS '04. Proceedings. 2004, 2004
A new method for wind-field retrieval with spatially and temporally high-resolution using marine radar-image sequences is presented. The method is based on analyzing the movement of wind gusts, which become visible in radar image sequences after filtering.
Heiko Dankert, Jochen Horstmann, Wolfgang Rosenthal   +2 more
openaire   +2 more sources

Ship detection in marine radar images based on a modified YOLOv3-tiny

IET Conference Proceedings, 2021
Deep learning has shown great success on object detection task for optical images, yet it’s rarely used in marine radar target detection. It is mainly due to the scarce of the labelled marine radar datasets for deep learning. To mitigate such effect, we build a pseudo-color marine radar dataset, which utilizes rich temporal information to remarkably ...
Y. Lei, L. Si, L. Sun, F. Xu
openaire   +1 more source

Observation of tide from X-band marine radar image sequences

2016 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2016
Tide has been monitored by tide-gauge stations and spaceborne radar altimeters. A new method to estimate the characteristics of coastal tide from X-band marine radar image sequences is proposed. The significant wave height (SWH) is firstly retrieved from X-band marine radar image sequence, and then filtered to remove the influences of noises.
Zhongbiao Chen, Yijun He 0004, Jiayi Pan 0001, Biao Zhang 0001, Xiaoqing Chu   +4 more
openaire   +1 more source

Rain Detection From X-Band Marine Radar Images

2019 IEEE Radar Conference (RadarConf), 2019
A method based on support vector machines (SVMs) is proposed to detect rain from X-band marine radar images. First, each image is labeled as rain-free or rain-contaminated according to the simultaneous rain rate data provided by a rain gauge. Then, feature vector is extracted from each image, which consists of the normalized histogram bin values.
Xinwei Chen, Weimin Huang
openaire   +1 more source

Processing method of marine radar image based on wavelet transform

2013 IEEE 11th International Conference on Electronic Measurement & Instruments, 2013
Marine radar image often has a lot of noise signal, the noise ratio of the radar image is very low. So a method based on a combination of wavelet transform, K-distributed sea clutter threshold segmentation and most of the interpolation repair method is presented in this paper, which can deal with the same frequency noise of marine radar image.
Dong Jingwei, Wei Xiaowei, Li Huile, Li Juyan   +3 more
openaire   +1 more source