Simplified Real‐Time Imaging Flow for High‐Resolution FMCW SAR

IEICE Electron. Express

Nie

et al. 2021

The airborne sensors with high data rate demand the onboard high-speed storage system due to the limited bandwidth of the downlinks. The NAND Flash and its products are the most common storage medium, and the conventional FAT file system is widely used in the storage systems. However, there has been a problem in recording the live high-speed data stably with this file system. The management time of the FAT file system is relatively long due to the internal overhead which includes the retrieving and updating of the FAT and FDT. The aim of this study is to investigate the technology for the real-time file system. A technology called FPFPA (FAT post-and FDT post-allocation) method is presented to solve this problem. To evaluate the performance of the proposed method, the management time of the file system using our proposed method is tested on the high-speed storage system of an airborne radar. The result indicates that the proposed method achieves our goal successfully in that the management time of the file system is significantly reduced and sufficiently small.

“…The space with the size of 4B in FAT is used to describe the linking relationship of a cluster. Two duplicated FATs are maintained for robustness in the FAT file system [20,21,22,23].…”

Section: Introductionmentioning

confidence: 99%

A new technology for real-time file system of high-speed storage system in airborne sensors

IEICE Electron. Express

Nie

et al. 2021

“…It can adapt to the application scenarios of severe aircraft vibration and harsh working environment and can fully meet the requirement of high storage rate [5,11]. Like other data storage systems, the NAND flash-based onboard storage system also needs file system to manage its internal space, so that the data in the system can be read, written, copied and deleted by the user after the storage [12][13][14][15].…”

Section: Introductionmentioning

confidence: 99%

Study on the file management method of data storage system for airborne radar

Nie

et al. 2021

R. Soc. open sci.

In order to solve the problem that the air-to-ground data transfer rate is much lower than the radar data rate, the onboard system is commonly used for storing the airborne radar data. However, there are two main problems in the data storage using the traditional file management method. The first is that the frequent data updating of the file allocation table (FAT) and the file directory table (FDT) cause a high frequency of address jumps among the discontinuous areas, which leads to a long response time. The second is that the updating frequencies of the FAT, the FDT and the data region are seriously inconsistent, which results in uneven wear of the three areas. To solve these two problems, a file management method, which optimizes the data writing in the three areas of the FAT, the FDT and the data region, is proposed in this study. An actual measurement is carried out on a data storage system of the airborne radar using the proposed file management method. The result shows that the proposed method significantly reduces the updating frequency of FAT and FDT, and achieves the wear levelling of file area and data region.

“…Frequency-modulated continuous-wave (FMCW) synthetic aperture radar (SAR) system paves the way for high-resolution radar imaging with flexibility, low cost, and low power; therefore, it has become the hotspot in the radar field 1 – 5 With the increase of the scene size and the improvement of the resolution, the data rate of the airborne FMCW SAR is in the order of dozens of megabyte per second.…”

Section: Introductionmentioning

confidence: 99%

Study on an onboard data storage system for frequency-modulated continuous-wave synthetic aperture radar

Chang

et al. 2016

J. Appl. Remote Sens

.The airborne frequency-modulated continuous-wave synthetic aperture radar presents an enormous technical challenge on the design of data storage system due to its characteristics of high-data rate, small size, light weight, and low-power consumption. There are two main problems for the high-speed storage under the miniature requirement. One is the unpredictable response time of the flash translation layer in the CompactFlash card. The other is the relatively long response time of the file system. This paper designs a data storage system in a real-time signal processor. Two techniques called configurable buffer structure and FPFQA (FAT pre- and FDT quasiallocation) are presented to overcome these two problems. The evaluated performance indicates that the size, power consumption, and weight meet the miniature requirement, while the function of the high-speed data storage with approximately 121 MB/s storage speed and real-time file management are realized.