电子与信息学报
電子與信息學報
전자여신식학보
JOURNAL OF ELECTRONICS & INFORMATION TECHNOLOGY
2014年
10期
2497-2503
,共7页
鲍青柳%董晓龙%林文明%朱迪%徐星欧
鮑青柳%董曉龍%林文明%硃迪%徐星歐
포청류%동효룡%림문명%주적%서성구
雷达波谱仪%信号仿真%方向谱%各向异性
雷達波譜儀%信號倣真%方嚮譜%各嚮異性
뢰체파보의%신호방진%방향보%각향이성
Radar spectrometer%Simulation based on signal flow%Directional spectrum%Anisotropy
为研究星载真实孔径雷达波谱仪信号预处理及海浪谱反演方法,该文建立了雷达波谱仪信号仿真模型,阐述了海浪调制谱和方向谱的信号仿真流程。对不同海浪谱模型,不同海况条件下的海面进行仿真,结果表明反演得到的调制谱与参考调制谱具有良好的一致性。同时,海面各向异性对海浪方向谱的反演存在影响,进而提出了通过拟合不同方位向雷达后向散射系数随入射角的变化曲线的方法。利用归一化调制系数的方位向变化规律修正海面各向异性对海浪方向谱反演的影响。仿真结果表明,在噪声条件和无噪条件下,经过调制系数修正后,反演方向谱与参考方向谱的误差明显减小。尤其是在风浪和涌浪同时存在且方向互相垂直的海况条件下,方向谱积分能量误差由20%下降到2%以下。
為研究星載真實孔徑雷達波譜儀信號預處理及海浪譜反縯方法,該文建立瞭雷達波譜儀信號倣真模型,闡述瞭海浪調製譜和方嚮譜的信號倣真流程。對不同海浪譜模型,不同海況條件下的海麵進行倣真,結果錶明反縯得到的調製譜與參攷調製譜具有良好的一緻性。同時,海麵各嚮異性對海浪方嚮譜的反縯存在影響,進而提齣瞭通過擬閤不同方位嚮雷達後嚮散射繫數隨入射角的變化麯線的方法。利用歸一化調製繫數的方位嚮變化規律脩正海麵各嚮異性對海浪方嚮譜反縯的影響。倣真結果錶明,在譟聲條件和無譟條件下,經過調製繫數脩正後,反縯方嚮譜與參攷方嚮譜的誤差明顯減小。尤其是在風浪和湧浪同時存在且方嚮互相垂直的海況條件下,方嚮譜積分能量誤差由20%下降到2%以下。
위연구성재진실공경뢰체파보의신호예처리급해랑보반연방법,해문건립료뢰체파보의신호방진모형,천술료해랑조제보화방향보적신호방진류정。대불동해랑보모형,불동해황조건하적해면진행방진,결과표명반연득도적조제보여삼고조제보구유량호적일치성。동시,해면각향이성대해랑방향보적반연존재영향,진이제출료통과의합불동방위향뢰체후향산사계수수입사각적변화곡선적방법。이용귀일화조제계수적방위향변화규률수정해면각향이성대해랑방향보반연적영향。방진결과표명,재조성조건화무조조건하,경과조제계수수정후,반연방향보여삼고방향보적오차명현감소。우기시재풍랑화용랑동시존재차방향호상수직적해황조건하,방향보적분능량오차유20%하강도2%이하。
In order to research the signal preprocessing and the inversion method of the ocean wave, the simulation model of a space-borne real aperture radar spectrometer based on signal flow is established. The block diagrams for the modulation spectrum and directional spectrum simulation are provided. Using the simulation model, different ocean wave spectrum model and ocean conditons are simulated. The results show that the retrieved modulation spectrum and referenced modulation spectrum are highly related. What is more, a method used to correct the influence of the ocean anisotropy is proposed. The ocean anisotropy can be corrected by using the normalized modulation coefficient. The simulation results show that the directional spectrum retrieval error is significantly reduced after modulation coefficient correction, especially in the conditon that wind wave and swell wave exist simultaneously and are vertical to each other. The energy integral error of directional spectrum reduces to 2%from 20%.