Ocean Target Investigation Using Spaceborne SAR under Dual-Polarization Strip-map Mode

Guo, Rui; Zhang, Zhao; Gao, Rui; Guobin, Jing; Xing, Mengdao; Zhi, Yongfeng

doi:10.23919/ciss51089.2021.9652375

Cited by 4 publications

(2 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(c) When the tissues are considered to be at a distance of 4 cm, the results are better, the SAR values being exceeded only in the skin tissue; thus, the solution to be in the standard limits would be to place the antenna at a distance larger than 4 cm from the human tissues, as it can be observed in Figure 20. The values of SAR change based on the material characteristics, making it an important parameter that can be used also in applications such as the mapping of snow covering some regions [29], crop mapping [30,31], flood [32] or terrain mapping [33], giving our antenna purposes if the values exceed the ones that are accepted according to the standards in force for the antenna to be in the close vicinity of the human body or embedded in its clothes or near equipment.…”

Section: Specific Absorption Rates and Radiated Power Density In The ...mentioning

confidence: 99%

High Gain Improved Planar Yagi Uda Antenna for 2.4 GHz Applications and Its Influence on Human Tissues

et al. 2023

View full text Add to dashboard Cite

Considering the technological enhancements nowadays, antennas tend to be smaller in order to be easily integrated in devices. The most used antennas today in small high-tech devices close to the human body are planar antennas. In this paper, a Yagi Uda planar antenna operating at a frequency of 2.4 GHz is HF analyzed and optimized by increasing its bandwidth and gain while maintaining its initial dimensions. The methods used to optimize the antenna’s operation are the use of different dielectrics, different numbers of directors, and different dimensions for directors, placing new conductor elements, all while keeping the same dimensions for its implementation on the planar device. The optimized structure of the planar Yagi Uda antenna has a 10% increase in bandwidth and a 30% increase in gain, reaching a peak value of 4.84 dBi. In our daily activities, we use devices with such antennas very often, so an analysis of the antenna’s influence on the human body is performed: the SAR, electric and magnetic field and radiation power density are determined, represented and reported to the standards in force. For the frequency considered, the SAR should be below 4 W/kg for the head/torso when the exposure is more than six minutes, which is a value exceeded by the antenna in its near vicinity. The calculated maximum electric field limit is 0.349 V/m and the maximum magnetic field value is 28.441 V/m for an exposure between 6 and 30 min values, which is also exceeded in the immediate vicinity of the antenna. The results allow us to suggest that such an antenna should be placed further from the human body, or some protection should be placed between the body and the antenna. From the radiation power density point of view for the modeled antenna, it can be said that a distance from the antenna greater than 0.5 m is considered to be safe.

show abstract

Section: Specific Absorption Rates and Radiated Power Density In The ...mentioning

confidence: 99%

High Gain Improved Planar Yagi Uda Antenna for 2.4 GHz Applications and Its Influence on Human Tissues

et al. 2023

View full text Add to dashboard Cite

show abstract

“…Researchers are focused on improving its imaging quality [ 4 ]. SAR images can be obtained through airborne or spaceborne platforms, and SAR can operate in either strip mode [ 5 ] or scan mode, depending on the imaging needs. Figure 1 depicts the schematic diagram of the two modes of SAR imaging using a satellite.…”

Section: Introductionmentioning

confidence: 99%

Hardware Accelerated Design of a Dual-Mode Refocusing Algorithm for SAR Imaging Systems

2023

Sensors

View full text Add to dashboard Cite

The use of satellite synthetic aperture radar (SAR) for moving target imaging has gained popularity recently. Researchers are focused on improving its imaging quality. To achieve high-quality and fast imaging, we have developed a dual-mode refocusing algorithm. We optimized the algorithm’s target speed estimation and carried out data enhancement and quantization design for SAR image refocusing. The design is implemented on a Xilinx XC5VFX130T FPGA. The dual-mode image data are based on a slice size of 512 × 512 for slice mode and 256 × 256 for scan mode in a time-series function simulation. The serial–parallel conversion and pipeline design balances the operating speed and logic resources for optimal performance. Experiment results on slice data of real SAR images show that the system’s processing speed can reach two frames per second, utilizing 69633 LUTs, 255 RAMs, and 296 DSPs.

show abstract

Research on the Evaluation Mechanism of Spaceborne SAR system to Ground-Based Radar Co-Frequency Interference

Sun

Peng

Liu

et al. 2022

2022 3rd China International SAR Symposium (CISS)

View full text Add to dashboard Cite

Ocean Target Investigation Using Spaceborne SAR under Dual-Polarization Strip-map Mode

Cited by 4 publications

References 9 publications

High Gain Improved Planar Yagi Uda Antenna for 2.4 GHz Applications and Its Influence on Human Tissues

High Gain Improved Planar Yagi Uda Antenna for 2.4 GHz Applications and Its Influence on Human Tissues

Hardware Accelerated Design of a Dual-Mode Refocusing Algorithm for SAR Imaging Systems

Research on the Evaluation Mechanism of Spaceborne SAR system to Ground-Based Radar Co-Frequency Interference

Contact Info

Product

Resources

About