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[ABSTRACT]The recent development of semiconductor technology has achieved downsized, large-scaled and low-power VLSI (Very Large-Scale Integration) systems. However, it makes the soft error issue more serious. Soft errors occur due to a transient-induced event caused by striking of high energy neutron radiation from cosmic rays. The striking on the silicon bulk generates electrons and holes, which are collected at a drain node. The collected electrons or holes lead to transient voltage. As a result, values erroneously change in storage elements, such as memory. Traditionally only soft errors on memory system have been serious. However, in recent VLSI systems, soft errors on logic circuit as well as memory system are also serious because recent VLSIs do not tolerate pulses with a short period of time vibration phenomenon. To resolve this issue, researchers (including the authors' group) have presented several soft error tolerate schemes. Most of them provide only simulation results; it is not known that which scheme is best in actual devices. We are making experimentation on an actual device. In this experimentation, several flip-flops are mounted on the actual device; the mounted flip-flops consist of several existing soft error hardened latches, such as DICE, and normal latches not hardened. Neutron beam is delivered to the device. The device is observed by an observation equipment mounted on Raspberry Pi during radiation.

[ABSTRACT]Synthetic Aperture Radar (SAR) is a class of multipurpose sensors, which can operate in all-weather and day-night time. In Chiba University, We have a plan a verification experiment for Circularly Polarized SAR (CP-SAR) using Unmanned Aerial Vehicle (UAV). Since CP wave is not affected by an ionosphere, it’s expected to allow for more precise observation. Raw image data received by CP-SAR needs to be applied image processing, but it will not be processed on the ground. Considering the communication time, only the image processed on UAV is sent. Our previous image processing system needs high power consumption and takes up space because it uses Vertex-6 FPGA Board ML605, Spartan-6 FPGA Board SP605 and one PC which has Intel Atom processor and a Solid State Drive (SSD). In this system, Range Doppler Algorithm (RDA) which is major image processing algorithm for SAR is executed in ML605 and the others is used to save the image to SSD. Our proposed system only uses Kintex-7 FPGA Board KC-705 with XM104 Connectivity Card. XM104 makes it possible for KC-705 to use SATA; it can connect SSD without a PC. It’s expected to reduce power consumption, space, time of development and modification. Our CP-SAR image processing system is required semi-real-time observation. KC705 has high performance than ML605 so we expect it to satisfy this requirement and to reduce image processing time. The proposed system is applicable to SAR image processing system on an UAV making semi-real-time observation.

[ABSTRACT]Synthetic Aperture Radar (SAR) is a class of multipurpose sensors, which can operate in all-weather and day-night time. Circular Polarization SAR (CP-SAR) is less subject to the ionosphere of the earth, and thus it is expected to improve accuracy of observation. We are requested to reduce the size of SAR image data by making on-board SAR image processing on a flight platform. From such a viewpoint, an on-board SAR image processing system is developed for the unmanned aerial vehicle (UAV) with the CP-SAR. This paper shows an on-board SAR image processing system on an UAV. This radar system is required semi-real-time observation. The proposed system is composed of two FPGA evaluation boards and a PC. One board makes SAR image processing using Range-Doppler-Algorithm (RDA). The other board and the PC has Intel Atom processor and a Solid State Drive (SSD) are used to store data. The proposed system processes a SAR image in 32 seconds or less at a guess. This indicates that the proposed system is applicable to an on-board SAR image processing system on an UAV making semi-real-time observation.

[ABSTRACT]We are developing a microsatellite with a circularly polarized synthetic aperture radar (CP-SAR). In this project an unmanned aerial vehicle (UAV) of CP-SAR loading is being developed for a preparation experiment prior to development of a micro satellite. To accomplish image processing on the image obtained by the radar, we are studying image processing system using Field Programmable Gate Array (FPGA). This paper presents a UAV on-board semi-real-time SAR image processing system. In addition, a sample raw data is processed in the implemented system and is compared to a data generated on PC, which gives evidence that the designed system provides processed image with sufficient high accuracy.