已为您找到该学者56条结果 成果回收站
【期刊论文】FFT-Based Efficient Algorithms for Time Delay Estimation
吴仁彪, Renbiao Wu, Wenyi Wang, Qiongqiong Jia.
invited chapter in 《Fourier Transform/Book 1》, INTECH Open Access Publisher, 2011.,-0001,():
-1年11月30日
-
22浏览
-
0点赞
-
0收藏
-
0分享
-
42下载
-
0
-
引用
【期刊论文】Joint Subcarrier Matching and Power Allocation for OFDM Multihop System
吴仁彪, Wengyi, Wang Renbiao Wu.
invited chapter in 《Communications and Networking》, SCIYO, 2010.,-0001,():
-1年11月30日
-
24浏览
-
0点赞
-
0收藏
-
0分享
-
32下载
-
0
-
引用
【期刊论文】Time-delay- and time-reversal-based robust Capon beamformers for ultrasound imaging
吴仁彪, Zhisong Wang, Jian Li, and Renbiao Wu.
IEEE Transactions on Medical Imaging, 2005, Vol.24, No.10, pp. 1308-1322.,-0001,():
-1年11月30日
Currently, the nonadaptive delay-and-sum (DAS) beamformer is extensively used for ultrasound imaging, despite the fact that it has lower resolution and worse interference suppression capability than the adaptive standard Capon beamformer (SCB) if the steering vector corresponding to the signal of interest (SOI) is accurately known. The main problem which restricts the use of SCB, however, is that SCB lacks robustness against steering vector errors that are inevitable in practice. Whenever this happens, the performance of SCB may become worse than that of DAS. Therefore, a robust adaptive beamformer is desirable to maintain the robustness of DAS and adaptivity of SCB. In this paper we consider a recent promising robust Capon beamformer (RCB) for ultrasound imaging. We propose two ways of implementing RCB, one based on time delay and the other based on time reversal. RCB extends SCB by allowing the array steering vector to be within an uncertainty set. Hence, it restores the appeal of SCB including its high resolution and superb interference suppression capabilities, and also retains the attractiveness of DAS including its robustness against steering vector errors. The time-delay-based RCB can tolerate the misalignment of data samples and the time-reversal-based RCB can withstand the uncertainty of the Green’s function. Both time-delay-based RCB and time-reversal-based RCB can be efficiently computed at a comparable cost to SCB. The excellent performances of the proposed robust adaptive beamforming approaches are demonstrated via a number of simulated and experimental examples.
Adaptive arrays,, array errors,, interference suppression,, robust adaptive beamforming,, robust Capon beamforming,, time delay,, time reversal,, ultrasound imaging.,
-
51浏览
-
0点赞
-
0收藏
-
0分享
-
3下载
-
0
-
引用
【期刊论文】Microwave imaging via adaptive beamforming methods for breast cancer detection
吴仁彪, Guo B, Wang, Y W, Li J, Stoica P, Wu R B.
Journal of Electromagnetic Waves and Applications, 2006, Vol.20, No.1, pp.53-63.,-0001,():
-1年11月30日
Ultra-wideband (UWB) Microwave imaging (MWI) is a promising breast cancer detection technology which exploits the significant contrast in dielectric properties between normal breast tissue and tumor. Previously, data-independent methods, such as delay-and-sum (DAS) and space-time (ST) beamforming, have been used for microwave imaging. However, the low resolution and the poor interference suppression capability associated with the dataindependent methods restrict their use in practice, especially when the noise is high and the backscattered signals are weak. In this paper, we develop two data-adaptive methods for microwave imaging, which are referred to as the robust weighted Capon beamforming (RWCB) method and the amplitude and phase estimation (APES) method. Due to their data-adaptive nature, these methods outperform their dataindependent counterparts in terms of improved resolution and reduced sidelobe levels.
-
16浏览
-
0点赞
-
0收藏
-
0分享
-
3下载
-
0
-
引用
-
79浏览
-
0点赞
-
0收藏
-
1分享
-
3下载
-
0
-
引用