曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
The Multi-Platform Radar Technology Insertion Program (MP-RTIP) should result in a more capable SAR active electronically steered antenna (AESA) within this decade. Larger UA, such as Global Hawk for the Air Force and potentially for the Navy’s Broad Area Maritime Surveillance (BAMS) role, are one intended recipient of this technology. AESA permits mission expansion into an air surveillance role, as air-to-air operation is easily accomplished using AESA technology. In a similar fashion, maritime modes of operation, such as inverse SAR (ISAR) image generation of ships at sea, may be employed with good results. Combined with conformal antennas, large AESA-based SAR systems may be able to achieve greater imaging and MTI capabilities as well as more specialized missions, such as single pass interferometric SAR.
At the opposite end of the spectrum, vendors are taking advantage of the decreasing cost of radio frequency (RF) technologies applicable to radar systems (driven primarily by the telecommunications industry), to develop versions of sensors for tactical and lower payload class aircraft. For example, the MISAR system is capable of imaging truck-sized targets at approximately 3.5 km slant range, from a tactical class platform, even though the sensor is in the 10-pound weight class. While MISAR currently does not form images on-board, there is fundamentally no reason this capability could not be integrated within a reasonable weight margin, permitting consumers of the raw data to tap the unformed image information from the raw feed, while tactical users could received a formed image – both from the same platform.
UHF/VHF Foliage Penetration (FOPEN) SAR. In FY-97 DARPA, the Army and the Air Force began a program that designed, fabricated and demonstrated a dual-band VHF/UHF radar with real-time onboard image formation processing. The VHF/UHF SAR hardware is currently being flown on an Army-owned RC-12 aircraft. The system was developed to target multiple platforms with little modification; one such system is the Global Hawk UA. The sensor development program ended in 2003. In FY03, DARPA began the Wide-Area All-Terrain Change Indication and Tomography (WATCH-IT) program to enhance,
APPENDIX B – SENSORS
Page B-4
mature, and integrate exploitation technologies. The WATCH-IT program developed robust low false alarm density change detection software to detect vehicles and smaller targets under foliage, under camouflage and in urban clutter, and developed tomographic (3D) imaging to detect and identify targets that have not relocated. DARPA demonstrated the capability of VHF/UHF SAR for building penetration, urban mapping and performing change detection of objects inside buildings. Terrain characterization technologies were also developed, including the abilities to rapidly generate bald-earth terrain height estimates and to classify terrain features from multipass VHF/UHF SAR imagery. In September 2004, DARPA demonstrated real-time onboard change detection (vehicles and IEDs) and rapid ground-station tomographic processing, as well as rapid generation of bald earth digital elevation models (DEMs) using stereo processing. In parallel, the Air Force Targets Under Trees (TUT) program enhanced the VHF SAR by adding a 10-km swath width VHF-only mode, developing a real-time VHF change detection capability and integrating FOPEN products into the targeting chain. In the summer of 2004, the VHF/UHF SAR participated in the Combined Joint Task Force Exercise (CJTFEX-04) and the Joint Expeditionary Forces Experiment (JEFX04). The system demonstrated real-time VHF-change detection and validated the ability of VHF/UHF SAR to operate with other sensors. TUT provided real-time VHF change detection cues to the Combined Air Operations Center (CAOC) and successfully tasked another sensor in real time (a Predator surrogate with an EO/IR package) to prosecute mobile relocatable targets.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
无人机系统路线图 Unmanned Aircraft Systems Roadmap(99)
