高效計(jì)算與isar成像

1、UGM培訓(xùn)：RCS高效計(jì)算與ISAR成像1© 2016 ANSYS, Inc.July 3, 2018ANSYS內(nèi)容提要RCS概述電大、復(fù)雜度高、大規(guī)模計(jì)算解決方案FEM+IE+SBR、HPC操作演示SBR用于RCS計(jì)算、ISAR成像上機(jī)與答疑2© 2016 ANSYS, Inc.July 3, 2018ANSYS12345RCS 定義Radar Cross Section𝐸𝑠 2，Es 、Ei 分別表示散射和入射電場 數(shù)學(xué)上，RCS 定義為：𝜎4𝜋𝑟2= lim𝑟3Ү

2、63;𝐸𝑖 2 物理上，RCS 是目標(biāo)有效反射面積的度量，或指定方向上散射功率對(duì)入射功率歸一化的度量 當(dāng)發(fā)射機(jī)和 當(dāng)發(fā)射機(jī)和 RCS 用面積在同一位置時(shí)，稱為單站RCS（Monostatic RCS ）有一定距離間隔時(shí)，稱為雙站 RCS （Bistatic RCS ）表示（例如，𝜎 = 1m2） ，通常也表示為為dBsm或（𝜎𝜆2）雙站雷達(dá)單站雷達(dá)3© 2016 ANSYS, Inc.July 3, 2018ANSYS發(fā)展趨勢目標(biāo)電 飛機(jī)、越來越大、艦船結(jié)構(gòu)復(fù)雜度越來越高RCS的特殊應(yīng)用 熱點(diǎn)處理、RCS

3、成像 近場/天線陣/時(shí)域的RCS凹腔、進(jìn)氣道隱身材料涂覆結(jié)構(gòu)型隱身材料、FSS 同時(shí)包含結(jié)構(gòu)細(xì)節(jié) 考慮機(jī)載天線影響44© 2016 ANSYS, Inc.July 3, 2018ANSYS適合的算法 FEM適合涂層、FSS、天線等復(fù)雜目標(biāo) IE法適合電大金屬體 單一的算法無法解決電大且復(fù)雜的問題5© 2016 ANSYS, Inc.July 3, 2018ANSYS快速、高效的求解Incident Wave 必需有高效率的并行技術(shù) 支持分布式節(jié)點(diǎn)Front ViewTop View6© 2016 ANSYS, Inc.July 3, 2018ANSYSMesh #

4、RAMElapsed Time10GHz5.03 million15.4 G27.5 minutes18GHz16.19 million50.6G174.5 minutes解決方案7© 2016 ANSYS, Inc.July 3, 2018ANSYSHFSS算法體系HPC+DDMShooting and Bouncing RaysThe ANSYS SolutionHFSS-IE & FEBIHFSS: Finite ElementsGeometry and Material Complexity Geometry and Material Complexity8©

5、; 2016 ANSYS, Inc.July 3, 2018ANSYSElectrical SizeHighlight in R19: SBR+計(jì)算RCS1stParametric mof missile launchMonostatic RCS in azimuth plane9© 2016 ANSYS, Inc.July 3, 2018ANSYSSBR Solver:彈跳射線法求解器Shooting and Bouncing Rays 高頻近似算法作為全波求解器的有效補(bǔ)充主要ANSYS SBR+技術(shù)電大平臺(tái)問題（i.e.,達(dá)成百上千波長） 物理繞射理論(PTD) 爬行波(Cree

6、Wave) 一致性繞射理論 (UTD) 曲面發(fā)散因子HPC/GPU10© 2016 ANSYS, Inc.July 3, 2018ANSYSSBR-Region 混合邊界SBR 能以高精度、高效率SBR求解超大規(guī)模問題11© 2016 ANSYS, Inc.July 3, 2018ANSYS中的應(yīng)用RCS FE-BI、IE-Regions、SBR/PO-Regions大混合 更大、更快、更合理有限元FE-BIIE-RegionSBR/PO-Region12© 2016 ANSYS, Inc.July 3, 2018ANSYSSBR+的精度Frequency =5G

7、Hz;Wavelength = 6cmMax dimension 12 0.5mTrihedral Comparison at 5GHzSBR+ solution:12 seconds on a laptop with 45MB RAMFEM solution: hours to solve on 20cores and over 100GB RAMIE solution:40x faster, < 50% RAMSBR+ Region with Wedges(PTD/UTD)FEM with PML BoundaryIE Region13© 2016 ANSYS, Inc.J

8、uly 3, 2018ANSYS角反RCS結(jié)果對(duì)比14© 2016 ANSYS, Inc.July 3, 2018ANSYS更大規(guī)模的RCS精度對(duì)比15© 2016 ANSYS, Inc.July 3, 2018ANSYS超大規(guī)模RCS計(jì)算Lossy sea water surfaceincluded in SBR+ Analysis16© 2016 ANSYS, Inc.July 3, 2018ANSYS超大規(guī)模RCS計(jì)算Monostatic RCS of ISS at 10GHz on the order ofseveral minutes using SBR

9、+17© 2016 ANSYS, Inc.July 3, 2018ANSYS3500 10 GHzMonostatic RCS 10 GHzISARInverse synthetic aperture radarSignal processing technique used to reconstruct radar image of targetsGenerated from frequency dependent scattered fields at differentlook anglesTypical UsageTarget classification Identify

10、scattering centers𝒚𝒎𝒂𝒙=𝒙𝒎𝒂𝒙𝑵𝑵𝒙 =𝒚𝒚𝒙𝒙𝒎𝒂𝒙𝒙Down Range Extents:Down Range Resolution:𝒄 𝟎𝟐 𝒙𝒎𝒂𝒙 &

11、#119940;𝟐 𝒚𝒎𝒂𝒙𝒇 =𝝋 =𝑩𝒂𝒏𝒅𝒘𝒊𝒅𝒕𝒉 = 𝒇 𝑵𝒙𝑨𝒔𝒑𝒆𝒄𝒕 𝑨𝒏𝒈𝒍𝒆 = 𝝋

12、 𝑵𝒚Simulation SettingsIFFT𝒚𝒎𝒂𝒙𝒚Cross Range Extents:Cross Range Resolution:Radar Requirements18© 2016 ANSYS, Inc.July 3, 2018ANSYSACT extension for Radar prePre-processing 定義距離、分辨率、頻率、極化 自動(dòng)設(shè)置成像需要的掃頻、結(jié)果輸出等設(shè)置19© 2016 ANSYS, Inc.July 3, 2

13、018ANSYSACT extension for Radar postPost-processing 成像處理range profile, waterfall and ISAR20© 2016 ANSYS, Inc.July 3, 2018ANSYS2nd Highlight in R19:RCS與成像得到RCSSBRACT 后處理成像 SBR+ 參數(shù)掃描64點(diǎn) 全波計(jì)算12.75hr SBR 僅 1hr21© 2016 ANSYS, Inc.July 3, 2018ANSYS汽車?yán)走_(dá)：成像與場景模擬22© 2016 ANSYS, Inc.July 3, 201

14、8ANSYSdemo：SBR+ for RCS simulation23© 2016 ANSYS, Inc.July 3, 2018ANSYSRCS demo in HFSS 19.11. Improt “at”2. Set material “Aluminum”24© 2016 ANSYS, Inc.July 3, 2018ANSYSDefine Solution Type3. HFSSSolution typeSBR+25© 2016 ANSYS, Inc.July 3, 2018ANSYSDefine Excitation for Monostatic RC

15、S4. HFSSExcitationAssignIncident wavePlane wave26© 2016 ANSYS, Inc.July 3, 2018ANSYS5. Setup settingcase1 : SBR onlycase2 : SBR with PTDcase3 : SBR with PTD+UTD27© 2016 ANSYS, Inc.July 3, 2018ANSYSHPC setting6. ToolsoptionsHPC and Analysis options28© 2016 ANSYS, Inc.July 3, 2018ANSYSS

16、imulation and Create RCS results7. HFSSAnalysis All8. HFSSResults Create Monostatic RCS Report29© 2016 ANSYS, Inc.July 3, 2018ANSYSMonostatic RCS results30© 2016 ANSYS, Inc.July 3, 2018ANSYSdemo：SBR+ for ISAR Image31© 2016 ANSYS, Inc.July 3, 2018ANSYSISAR demo in HFSS 19.11. Improt “a

17、t”2. Set material “Aluminum”32© 2016 ANSYS, Inc.July 3, 2018ANSYSDefine Solution Type3. HFSSSolution typeModal33© 2016 ANSYS, Inc.July 3, 2018ANSYSDefine SBR+ RegionHFSSHybrid Assign3. Select the tank mHybridSBR+ Region34© 2016 ANSYS, Inc.July 3, 2018ANSYSACT ToolkitRadar Pre4. ViewACT ExtentionsLanch WizardsRADAPre35© 2016 ANSYS, Inc.July 3, 2018ANSYSSimulation and RCS Results5. HFSSAnalysis All36© 2016 ANSYS, Inc.July 3, 2018