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synthetic apperture radar
milstar: Nize priwedenni primeri image i movie s dowolno wisokoj razreschajuschej sposobnost'ju 100 mm dlja SAR radara w diapazonax Ka(35ghz) i Ku waznejschij wopros dlja kakoj wojni . ######################## S-300 imelo porjadka 1500 yabch . W yslowijax podriwa serii yabch w atmosfere wse eto s xoroschim chansom ne budet rabotat' Bolee wisokuju boewuju ystojchiwost' budut imet' multimegawattnie rls s bolschoj apperturoj na lampax http://www.sandia.gov/RADAR/imageryka.html kollekzija image ot 35 ghz synthetic apperture radar razr.sposobnost' 4 inches -10 sm,100 millimetr Contact: To send feedback or request information about the contents of Sandia National Laboratories' synthetic aperture radar website, please contact: Nikki L. Angus Synthetic Aperture Radar Website Owner Sandia National Laboratories Albuquerque, NM 87185-1330 (505) 844-7776 (Phone) (505) 845-5491 (Fax) nlangus@sandia.gov http://www.sandia.gov/RADAR/movies.html kollekzija video s SAR Ku band i raz sposb 300 mm
milstar: 2.1. Near-zero inclination (NZI) GEO SAR The NZI GEO SAR scheme was first proposed by Tomiyasu from the National Aeronautics and Space Administration (NASA) of the U.S.A. in 1978 [10], and this proposal was also the first public report on the GEO SAR concept. He proposed that with the key orbital elements of 1° inclination, 90° argument of perigee (AoP) and 0.009 eccentricity, GEO SAR has a nearly circular nadir-point trajectory. GEO SAR has an effective velocity (the platform's velocity relative to the target) of 48 m/s, which can enable a 100 m resolution SAR image to be obtained in an integration time of 700 s. With an L-band radar, the whole North America continent can be imaged in 4 hours by switching footprints at a resolution of 100 m. Since 2000, with the rapid development of electronic technology, research on large antennas and high-power transmit/receive (T/R) module technology has made rapid progress, and thus, many studies of inclined GEO SAR have gained momentum again. In 2001, researchers at the Jet Propulsion Laboratory (JPL) in the U.S.A. pointed out that a GEO SAR with a large inclination (50°-65°) had great application prospects in disaster management, tectonic mapping and modeling. [22]. These scientists initially demonstrated the system requirements, including the power and antenna size requirements, and believed that the main technical difficulties that limited the realization of the scheme included the average transmission power of 15 kW and the 30 m aperture antenna. On the basis of this work, JPL proposed the Global Earthquake Satellite System (GESS, see the GEO SAR Constellation section below) in 2003 [23]. Ten inclined GEO SAR satellites were divided into five groups to achieve global coverage. Since then, American scholars have seldom published research on GEO SAR. To achieve a close or even better resolution performance as compared to LEO SAR, the synthetic aperture time of GEO SAR reaches hundreds of seconds. For a medium-inclination GEO SAR scheme with a small “figure 8” shape in the nadir-point trajectory, 1000 s of integration time is needed to obtain an azimuth-imaging resolution of 5 m at the orbit position above the equator. Long integration time yields the curve trajectory, resulting in a severe 2D spatial variation in the focusing parameters and range cell migration (RCM). There are two methods that can be used to solve this problem. One such method involves correcting the curve trajectory into a straight track during the imaging process [36]. However, only a very narrow swath can be accurately focused with this method, so the whole scene needs to be divided into very small segments that are each focused separately, significantly increasing the computational burden.
milstar: https://www.capellaspace.com/capella-unveils-worlds-highest-resolution-commercial-sar-imagery/ December 16, 2020 It has been a little over three months since the launch of our first operational satellite Capella-2 Capella is now the highest resolution commercial SAR provider in the world, capable of 50 cm x 50 cm resolution imaging. foto We are unveiling the highest resolution commercial SAR imagery available in the market at 50 cm x 50 cm resolution in our new Spotlight or “Spot” imaging mode. Our Spot product is a specialized mode that allows for long exposures over an area of interest (AOI) and results in a beautiful and crystal-clear SAR imagery. This new 50 cm x 50 cm imagery is collected by dwelling our satellites over an AOI for a long period. Think of it as a long exposure on your digital camera when you are trying to collect more light into your sensor. Except we are doing a very long exposure looking at a single location on Earth while traveling at 7.5 km per second in space. Our satellites have been designed with the capability to dwell on a single location for as long as 60 seconds. Performance Specifications Spotlight mode provides high resolution imaging at 0.25 meter azimuth resolution for a swath of 5 x 5 km. The sliding-spotlight mode produces an image at 0.5 meter azimuth resolution at a scene length up to 10 km. Stripmap mode produces imagery at 1.2 meter azimuth resolution up to 100 km x 10 km. Capella’s satellites operate in a variety of orbits at 45-degree mid-inclination (525 km altitude), 53-degree mid-inclination (575 km altitude), and 97-degree sun-synchronous orbit (525 km altitude). They have a period of 90 minutes which provides a revisit time of 2-5 hours with eight satellites. -------------------------------------------------------------------------------------- The Capella constellation will grow to 9 small satellites by the end of 2023. The constellation launched in 2018 with the initial deployment of one satellite. The radars are single polarization X-band systems, capable of operating at 500 - 700 MHz bandwidth in stripmap, spotlight, and sliding spotlight imaging modes. Capella continues to establish relationships with the U.S. government agencies after last year’s contracts with the U.S. Navy, U.S. Air Force, U.S. Space Force, National Geospatial-Intelligence Agency and the Pentagon Space Development Agency. G https://www.eoportal.org/satellite-missions/capella-x-sar#performance-specifications https://www.capellaspace.com/about-us/our-team/ Jeffrey K. Harris served as President of Lockheed Martin Missiles and Space and President of Lockheed Martin Special Programs. Director, National Reconnaissance Office, and Associate Executive Director of the Intelligence Community. https://www.capellaspace.com/about-us/our-team/jeffrey-harris/
milstar: High-Resolution Wide-Swath Imaging To overcome the trade-off limitation between resolution in azimuth versus spatial coverage, a novel imaging technique has been proposed [10]. This imaging mode combines digital beamforming on receive in elevation with multiple aperture recording in azimuth. This strategy enables the imaging of wide swath while simultaneously obtaining high resolution https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9739358/
milstar: https://earth.esa.int/eogateway/documents/20142/37627/ICEYE-SAR-Product-Guide-V4.pdf The ICEYE sensors are X-band radars, each with an active phased array antenna and electronic beam steering. The innate mechanical agility of these low-mass satellites and their electronic steering enable fast and precise point- ing of radar pulses to the ground. The satellites can also image to the right or left side of the satellite track. Technical parameters of the current sensors are listed in Table 2.1.
milstar: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7956687/ Ultra-High Resolution Imaging Method for Distributed Small Satellite Spotlight MIMO-SAR Based on Sub-Aperture Image Fusion
milstar: By reaching a SAR image resolution of 25 cm with small satellites, ICEYE sets a new standard in terms of stability and precision of small satellite systems and accurate SAR image processing. With this very high-resolution imaging capability of 25 cm, ICEYE data achieves the same resolution class as provided by conventional SAR satellites operating at their highest performance. https://www.iceye.com/blog/new-benchmark-in-imaging-from-sar-microsatellites-iceye-presents-25-cm-azimuth-resolution Figure 3. Floating roof oil tanks in Port of Rotterdam, The Netherlands. The 25 cm resolution mode provides a useful capability for tasks that require very precise measurements to be used. An example can be found in Figure 3 which is of an oil storage facility in Port of Rotterdam in the Netherlands Figure 4. Terminal and parking lots at Hartsfield-Jackson Atlanta International Airport, Georgia, US. This example shows the exceptionally empty parking lots at the Hartsfield-Jackson Atlanta International Airport in Georgia, US. Imaging in very high-resolution allows differentiating between individual cars for accurate counts. As you can see in Figure 4, distinguishing cars from other small metal structures like lamp posts and railings is still a non-trivial task, which is a topic for another post.
milstar: https://www.iceye.com/missions
milstar: Secondly the data management is depicted briefly. Chirp bandwidth is 300 MHz for 1m ground resolution at 30 deg off-nadir angle. The received signal is digitized with 8 bit at 720 M sampling/sec. The data compression rate is expected to be 50% and the received window in time domain is about 50%. Then generation rate of SAR data is about 1.5 Gbps and the total data volume for 5 minutes observa- tion is 56 GByte. This data is stored at a solid-state recorder with 1TByte capacity that can store data of 1.5 days’ obser- vation. Recently NAND flush memories with 62GByte per one device are available in the commercial market. Stor- age functions of NAND flush memory are essentially robust space radiation environments. We pay careful attentions to radiation-induced single event phe nomena at memory writing and reading https://www.jstage.jst.go.jp/article/transcom/E100.B/9/E100.B_2016PFI0008/_pdf/-char/en
milstar: The second part of the equation is L-3’s modem for the AESA radar. “This is the device that allows the movement of data across this network,” Bragg said. L-3’s current AESA modem, in its fourth generation, provides an extremely high data rate, Bragg said. “They've demonstrated 4.5 gigabits/sec, which for an airborne or ground-to-ground link is enormously fast — a record-setting speed for this kind of device.” https://www.defenseone.com/defense-systems/2009/07/radars-perform-double-duty-as-high-speed-data-links/188146/
milstar: to :https://guraran.ru/prezidiym_raran.html Сивков Константин Валентинович член президиума, заместитель президента Академии по связям с общественностью и информационной политике, доктор военных наук, действительный член РАРАН copy for information to : re: video c 3.35 Константин Сивков - это полетное задание готовится готовится не в украинских штабax.../ необязательно в штабax стран НАТО ...традиции английской внешней политики ,есть коммерческое предложение -снимки с рлс с синтезированной апертурой космического базирования с разрешением 25- 50 сантиметров,снимок приведен в email video c 3.35 https://www.youtube.com/watch?v=Q03YgPBHjRU ------------------------------------------------------------------------ Performance Specifications https://www.iceye.com/imaging-modes/dwell Spotlight mode provides high resolution imaging at 0.25 meter azimuth resolution for a swath of 5 x 5 km https://www.iceye.com/blog/new-benchmark-in-imaging-from-sar-microsatellites-iceye-presents-25-cm-azimuth-resolution https://www.iceye.com/imaging-modes/dwell Because of this requirement the new Spotlight mode has a native pixel spacing that is finer than the resolution (typically 0.125 m in azimuth and 0.25 m in range). Capella Unveils World’s Highest Resolution Commercial SAR Imagery https://www.capellaspace.com/capella-unveils-worlds-highest-resolution-commercial-sar-imagery/ традиции английской внешней политики ########################################### конечно это частные компании хорошо контролируются,делается это примерно так 1. какая нибудь частная компания "Geometeomonitoring" покупает симки у указанных выше Iceye,Capella 2. после того как кто то уволился из USA Space Command и подобныx организаций он становится пo международному праву юридически частным лицом которое оказывает консультации группе таких же частных лиц с украинским гражданством Government Advisory Board Clay Hutmacher is a former United States Army Officer, serving most recently as Director of Operations in the U.S. Special Operation Command https://www.capellaspace.com/about-us/our-team/clayton-hutmacher/ Jeffrey K. Harris Director, National Reconnaissance Office, and Associate Executive Director of the Intelligence Community. https://www.capellaspace.com/about-us/our-team/jeffrey-harris/
milstar: he Capella SAR, developed by Capella Space in the United States, is a 107 kg microsatellite SAR (Sequoia) that was successfully launched in 2020 [17,18,19,20]. In particular, this satellite features an X-band SAR payload that acquires spotlight-mode SAR images with a ground resolution of 0.5 m and uses a deployable tension–truss mesh reflector antenna with a 3.6 m diameter, similar to the AstroMesh [21] of the L-band SMAP SAR satellite or Oxford Space Systems [22], to minimize transmission power. This feature enables an outstanding continuous SAR image acquisition period of at least 9 min. The effective area of the Capella SAR antenna is 8 m2 compared with the 1.3 m2 antenna of ICEYE. Therefore, the Capella SAR antenna is more advantageous for obtaining higher SAR image quality, such as noise equivalent sigma zero (NESZ), than the ICEYE antenna. StriX-α is an X-band SAR microsatellite constellation containing 25 satellites, planned by Synspective in Japan, based on the development results of a prototype called MicroXSAR [23]. It is a 130 kg microsatellite that acquires SAR images with a ground resolution of 1–3 m. Specifically, Strix-α features a deployable passive phased-array antenna with 4.9 × 0.7 m honeycomb panels of a slotted waveguide array containing solar panels mounted on its rear. Furthermore, QPS-SAR is an X-band SAR microsatellite constellation developed by iQPS in Japan, and two launches have been completed in 2019 and 2021, respectively [24]. Similar to the Capella SAR, a total of 36 launches are planned for the QPS-SAR. These satellites use a deployable wrapped-rib parabolic mesh reflector antenna. This satellite weighs 100 kg with a 3.6 m diameter antenna that provides a high resolution of 1 m in spotlight mode and a standard resolution of 1.8 m in stripmap mode. https://www.mdpi.com/2226-4310/9/4/213
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