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An Efficient VLSI Architecture for motion compensation of AVS HDTV Decoder

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Journal of Computer Science & Technology 2006年第3期21卷 370-377页

作者：郑俊浩邓磊张鹏解晓东 Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 P.R. China Department of Computer Science Harbin Institute of Technology Harbin 150001 P.R. China Graduate University of Chinese Academy of Sciences Beijing 100039 P.R. China Grandview Semiconductor (Beijing) Corporation Beijing 100039 P.R. China

In the part 2 of advanced Audio Video coding Standard （AVS-P2）, many efficient coding tools are adopted in motion compensation, such as new motion vector prediction, symmetric matching, quarter precision interpolation, etc. However, these new features enormously increase the computational complexity and the memory bandwidth requirement, which make motion compensation a difficult component in the implementation of the AVS HDTV decoder. This paper proposes an efficient motion compensation architecture for AVS-P2 video standard up to the Level 6.2 of the Jizhun Profile. It has a macroblock-level pipelined structure which consists of MV predictor unit, reference fetch unit and pixel interpolation unit. The proposed architecture exploits the parallelism in the AVS motion compensation algorithm to accelerate the speed of operations and uses the dedicated design to optimize the memory access. And it has been integrated in a prototype chip which is fabricated with TSMC 0.18-#m CMOS technology, and the experimental results show that this architecture can achieve the real time AVS-P2 decoding for the HDTV 1080i （1920 - 1088 4 ： 2 ： 0 60field/s） video. The efficient design can work at the frequency of 148.5MHz and the total gate count is about 225K.

关键词： motion compensation AVS VLSI architecture

SAR motion compensation based on the correction of residual attitude errors

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Science China(Physics,Mechanics & Astronomy) 2011年第10期54卷 1899-1905页

作者： NI Chong WANG YanFei XU XiangHui ZHOU ChangYi Beijing Institute of Spacecraft System Engineering Beijing 100094 China Institute of Electronics Chinese Academy of Sciences Beijing 100190 China

As residual attitude errors are likely to affect the synthetic aperture radar (SAR) imaging, this paper presents a SAR motioncompensation algorithm based on the correction of residual attitude errors. The existing methods all use the antenna stableplatform to correct the attitude errors, and then compensate the trajectory deviations in the following imaging process. Besidescompensating the trajectory deviations, the modified method of this paper also considers the influence of residual attitude er-rors on the SAR imaging, and can compensate both the trajectory deviations and the residual attitude errors. Compared withthe existing methods, the modified method in this paper can more precisely compensate the imperfect motion on the SAR im-aging, especially good for the SAR system with a small platform, near operating distance and a narrow antenna beam. Such asystem causes severe residual attitude errors and needs to consider the influence of antenna beam pointing errors on the imag-ing. The validity of the modified method presented by this paper is demonstrated by the result of the experiment.

关键词： synthetic aperture radar residual attitude errors motion compensation

Improved spatio-SNR FGS video coding scheme using motion compensation on enhancement-layer

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Journal of Systems Engineering and Electronics 2006年第1期17卷 37-42页

作者： Jiang Tao Zhang Zhaoyang Ma Ran Shi Xuli Dept. of Electronic & Information Engineering School of Communication Shanghai Univ. Shanghai 200072 P. R. China

MPEG-4 fine-granularity-scalable （FGS） technology is an effective solution to resolve the network bandwidth varying because FGS provides very fine granular SNR scalability. However, this scalability is obtained with sacrifice of coding efficiency. An one-loop FGS structure is presented based on motion compensation （MC ＋ FGS） to improve the coding efficiency of base FGS. Then it describes and discusses the hybrid spatial-SNR FGS （FGSS） structure that extends SNR scalability of FGS to spatial scalability （spatio-SNR scalability）. FGSS structure inherent the low coding efficiency of FGS structure. Combining MC ＋ FGS structure with FGSS structure, a structure of MC ＋ FGSS structure is obtained which acquires both structures＇ advantages and counteracts both structures＇ defects. Experimental results prove the MC＋ FGSS structure not only obtains fine granular spatio-SNR scalability, but also achieves high coding efficiency.

关键词： fine-granularity-scalable coding efficiency motion compensation spatial scalability MPEG-4.

motion compensation FOR HIGH RESOLUTION AIRBORNE SAR WITH IMU & GPS

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Chinese Journal of Aeronautics 1999年第1期12卷 22-26页

作者：李立伟毛士艺

Inertial measurement unit (IMU) is a standard motion sensor in modern airborne SAR systems. But how to remove its systematic error is a difficult problem, which impacts the improvement of resolution in azimuth. The technique of motion compensation presented in this paper, uses the GPS as a reference system to estimate and correct the systematic error of the IMU on the concept of linear unbiased minimum variance (LUMV). This new and effective method achieves very accurate position measurement (both high and low frequency) of the APC in not only short but also long terms, so that it can satisfy the requirement of high resolution airborne SAR. In the last section of the paper, some experimental simulations from raw data are given.

关键词： motion compensation inertial measurement unit (IMU) global positioning system (GPS) linear unbiased minimum variance (LUMV) systematic error

Improved chirp scaling algorithm integrated motion compensation for parallel-track bistatic synthetic aperture radar

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Journal of Beijing Institute of Technology 2011年第4期20卷 536-539页

作者：齐春东曾涛李枫 School of Information and Electronics Beijing Institute of Technology

To compensate motion errors of images from the parallel-track bistatic synthetic aperture radar（BiSAR）,an improved chirp scaling algorithm（CSA） is *** velocity vector of the moving aircrafts in the parallel-track BiSAR system can not remain invariant in an aperture,an actual aperture is divided into subapertures so that it is reasonable to assume that the aircrafts move with constant acceleration vector in a *** on this model,an improved CSA is *** new phase factors incorporate three-dimensional acceleration and *** motion compensation procedure is integrated into the CSA without additional operation *** simulation results show that the presented algorithm can efficiently resolve motion compensation for parallel-track BiSAR.

关键词： chirp scaling algorithm parallel-track bistatic synthetic aperture radar motion compensation

RESEARCH ON motion compensation FOR HIGH RESOLUTION PROFILE OF EXTENDED TARGET FOR STEPPED CHIRP RADAR AND DSP IMPLEMENTATION

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Journal of Electronics(China) 2007年第2期24卷 191-198页

作者： Jiang Bin He Xiang Wang Hongqiang Guo Guirong ATR National Key Lab National University of Dcfcnse Technology Changsha 410073 China Beijing Univcrsity of Posts and Telccommunications Beijing 100876 China

A discrete model is set up for High Resolution Range Profile (HRRP) of an extended target and the model of echo from an extended target for a Stepped Chirp Radar (SCR) is proposed. The effect of target motion on a range profile is thoroughly analyzed, and based on which precision re- quirement is developed for motion compensation. By studying the time domain correlation and the rule based on the least burst error, a motion compensation algorithm which satisfies the project requirement is presented, and the cyber-emulation confirms the conclusion. At last the processor is designed by using DSP devices to realize motion compensation and target recognition.

关键词： Stepped chirp radar High Range Resolution Profile (HRRP) motion compensation The least burst error rule DSP implementation

IMPROVED SYNTHETIC APERTURE SONAR motion compensation COMBINED DPCA WITH SUB-APERTURE IMAGE CORRELATION

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Journal of Electronics(China) 2009年第2期26卷 191-197页

作者： Liu Wei Zhang Chunhua Liu Jiyuan Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China

Estimation precision of Displaced Phase Center Algorithm(DPCA) is affected by the number of displaced phase center pairs,the bandwidth of transmitting signal and many other *** analysis is made on DPCA's estimation *** results show that the directional vector estimation precision of DPCA is low,which will produce accumulating errors when phase cen-ters' track is *** of this reason,DPCA suffers from accumulating errors *** overcome this problem,a method combining DPCA with Sub Aperture Image Correlation(SAIC) is *** synthetic aperture is divided into *** errors in sub-aperture are estimated by DPCA and compensated to raw echo *** errors between sub-apertures are esti-mated by SAIC and compensated directly to sub-aperture *** that,sub-aperture images are directly used to generate ultimate SAS *** method is applied to the lake-trial dataset of a 20 kHz SAS prototype *** show the method can successfully remove the accumulating error and produce a better SAS image.

关键词： Synthetic Aperture Sonar(SAS) motion compensation Sub-aperture Image Correlation(IC)

Effects of residual motion compensation errors on the performance of airborne along-track interferometric SAR

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Frontiers of Information Technology & Electronic Engineering 2016年第10期17卷 1095-1105页

作者： Hui ZHANG Jun HONG Xiao-lan QIU Ji-chuan LI Fang-fang LI Feng MING Institute of Electronics Chinese Academy of Sciences Beoing 100190 China University of the Chinese Academy of Sciences Beijing 100190 China Key Laboratory of Technology in Geo-spatial Information Processing and Application Systems Beijing 100190 China Science and Technology on Millimeter-Wave Laboratory Beijing 100854 China

Two approximations, center-beam approximation and reference digital elevation model （DEM） approximation, are used in synthetic aperture radar （SAR） motion compensation procedures. They usually introduce residual motion compensation errors for airborne single-antenna SAR imaging and SAR interferometry. In this paper, we investigate the effects of residual uncompensated motion errors, which are caused by the above two approximations, on the performance of airborne along-track interferometric SAR （ATI-SAR）. The residual uncompensated errors caused by center-beam approximation in the absence and in the presence of elevation errors are derived, respectively. Airborne simulation parameters are used to verify the correctness of the analysis and to show the impacts of residual uncompensated errors on the interferometric phase errors for ATI-SAR. It is shown that the interferometric phase errors caused by the center-beam approximation with an accurate DEM could be neglected, while the interferometric phase errors caused by the center-beam approximation with an inaccurate DEM cannot be neglected when the elevation errors exceed a threshold. This research provides theoretical bases for the error source analysis and signal processing of airborne ATI-SAR.

关键词： Synthetic aperture radar (SAR) Along-track interferometric motion compensation Residual error Interferometric phase

New Realization Method for Airborne SAR motion compensation

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Journal of Beijing Institute of Technology 2004年第2期13卷 139-142页

作者：苏宏宇李舒李方慧龙腾 School of Information Science and Technology Beijing Institute of Technology Beijing100081 China

After analyzing the characteristics of airborne SAR motion deviation in detail, a new realization method for airborne SAR motion compensation based on two-dimensional division processing is described. By combining the division of local tracks in azimuth direction and the division of sub-mapping strips in range direction, the motion deviation will be compensated accurately. Furthermore, both theoretic analysis and simulation result show that by using this method the problems of motion compensation under complex condition with large motion deviation and large mapping strip width can be resolved well.

关键词： airborne SAR motion deviation motion compensation two-dimensional division local tracks sub-mapping strips