医学超声成像中的编码激励技术及其性能优化的研究
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摘要
在医学超声成像系统中，轴向分辨力、信噪比（探测深度）和对比度是衡量成像质量的主要指标。在传统短脉冲激励成像中，轴向分辨力和信噪比是一对难以调和的矛盾。而编码激励技术可以很好地解决这对矛盾。在发射端，对发射信号进行编码，在不提高发射信号的峰值功率下提高平均功率，从而提高系统的信噪比；在接收端，对回波信号进行脉冲压缩，恢复轴向分辨力。编码激励技术是提高超声成像质量的一种有效的方法，具有广阔的应用前景。在对现有理论和方法进行调研的基础上，本文提出了一些新的编码激励方法。其主要创新性成果有：
1）为了提高轴向分辨力和确保对比度，提出了一种基于幅度加权的预失真线性调频编码激励方法。该方法将线性调频发射信号幅度加权技术和回波信号旁瓣抑制技术相结合，一方面补偿超声探头对发射信号的影响，使得回波信号的带宽不局限于探头，提高轴向分辨力；另一方面消除发射信号幅频特性的菲涅耳波纹，提高发射信号的带宽并采用失配滤波器进行脉冲压缩，实现旁瓣抑制，确保成像对比度。仿真结果表明，与恒包络的线性调频编码激励相比，该方法不仅可以提高轴向分辨力，而且确保对比度；在轴向分辨力和对比度两方面，取得较好的折中效果。FieldII仿真B超图像结果同样证实该方法提高轴向分辨力。
2）传统Barker编码激励是采用单载频的正弦信号调制Barker编码的。本文中，提出了一种基于线性调频载波调制的Barker编码激励方法。对比正弦载波，线性调频载波的时间-带宽积可以大于1。因此，该方法通过提高载波带宽，可以提高轴向分辨力；另一方面，通过提高单位码片时间（即载波时间宽度），可以提高系统的信噪比。此外，系统的信噪比增益不仅能通过Barker码长获得，还可以通过载波的时间-带宽积获得。为了确保成像对比度，在脉冲压缩时，首先进行线性调频载波的脉冲压缩，然后进行Barker编码的脉冲压缩，实现旁瓣抑制。对于线性调频载波的脉冲压缩，当载波的时间-带宽积较小时，确保匹配滤波输出的主瓣内无旁瓣，此时只需要考虑匹配滤波器；当载波的时间-带宽积较大时，使得匹配滤波输出的主瓣内有旁瓣，此时需要考虑加切比雪夫窗的失配滤波器。对于Barker编码的脉冲压缩，采用基于峰值旁瓣水平最小的失配滤波器。仿真结果证明了所提出方法的有效性。
3）提出了一种基于伪chirp载波调制的Barker编码激励方法。与传统的基于正弦载波调制的Barker编码激励相比，该方法采用伪chirp载波调制Barker编码，可以优化轴向分辨力和系统的信噪比。与基于线性调频载波调制的Barker编码激励相比，该方法的编码信号幅值是二进制形式的，平均功率大，从而提高系统的信噪比，同时保持相近的轴向分辨力和对比度，而且发射激励电路简单。仿真结果证明了所提出方法的有效性。
4）提出了一种基于线性调频载波调制的Golay编码激励方法。与传统的基于正弦载波调制的Golay编码激励相比，该方法采用线性调频载波调制Golay互补序列对，可以优化轴向分辨力和系统的信噪比。与基于线性调频载波调制的Barker编码激励相比，该方法采用增加长度的Golay互补序列对，可以获得更高的信噪比及其增益，而且旁瓣幅度大大降低，因而增强成像对比度，同时保持相近的轴向分辨力。在脉冲压缩滤波器的设计中，对于Golay编码的脉冲压缩，只需要考虑匹配滤波器，脉冲压缩算法简单。仿真结果证明了所提出方法的有效性。
5）提出了一种基于线性调频载波调制的二进制最优编码激励方法。与基于线性调频载波调制的Barker编码激励相比，该方法使用增加长度的二进制最优序列，可以获得更高的信噪比及其增益，同时保持相近的轴向分辨力。与基于线性调频载波调制的Golay编码激励相比，该方法只需要发射信号一次，脉冲压缩性能不易受组织运动的影响。在脉冲压缩滤波器的设计中，对于二进制最优序列的脉冲压缩，采用基于最小均方误差的逆滤波器，实现旁瓣抑制，确保成像对比度。仿真结果证明了所提出方法的有效性。
In medical ultrasound imaging system, axial resolution, signal-to-noise ratio (SNR orpenetration) and contrast resolution are crucial factors to consider in evalution of imagequality. The tradeoff between axial resolution and SNR is well-known in conventionalsingle-pulse ultrasound system. However, coded excitation technique can well circumvent thisproblem. Here the duration of the excitation signal can be increased while maintaining thepeak power. More acoustic energy can be transmitted, thereby increasing the SNR. Axialresolution is usually recovered by compressing the echo signal in the receiver. The codedexcitation technique has been suggested as an efficient means of improving the quality ofultrasound imaging, so it has a wide application prospect. Based on a deep study on therelated theory and existing algorithms, the dissertation has developed some new methods onthe coded excitation. The main contributions are as follows.
1) In order to improve axial resolution and satisfy contrast resolution of medicalultrasound imaging, a predistorted linear frequency modulated (LFM) coded excitationmethod based on amplitude weighting is proposed. Combining the amplitude weightingtechnology of LFM transmit signal with the sidelobe reduction technology of echo signal, themethod on the one hand can compensate the influence of transducer impulse response on thetransmit signal, so the bandwidth of echo signal is not limited by the transducer and the axialresolution is improved. On the other hand, the method can remove the Fresnel ripples of thetransmit signal’s frequency response, increase its bandwidth and use mismatched filter withthe chebyshev window for pulse compression, so range sidelobes are suppressed to ensure thecontrast resolution. The simulation results reveal that, in contrast to constant-envelope LFMcoded excitation, the proposed method can improve axial resolution and satisfy contrastresolution of medical imaging, and achieve good compromise between axial resolution andcontrast resolution. FieldII Simulation results of B-mode image show that the axial resolutionof the proposed method is improved.
2) Traditionally, a single-frequency sinusoidal signal is used as the carrier of Barkercoded excitation. A Barker coded excitation method with LFM carrier is proposed. Incomparison with sinusoidal carrier, LFM carrier has the time-bandwidth product on the orderof above one. Thus, the method can improve axial resolution by increasing the bandwidth ofLFM carrier. On the other hand, the method can improve SNR by increasing the chip duration of Barker code, which is as large as the duration of LFM carrier. Moreover, SNR gain can beachieved not only by the length of Barker code but also by the time-bandwidth product ofLFM carrier. In order to ensure contrast resolution of medical imaging, pulse compressionscheme is developed to suppress sidelobes. It consists of two pulse compression filters forboth LFM carrier and Barker code, successively. With regard to the pulse compression ofLFM carrier, when the time-bandwidth of LFM carrier is low enough to have no sidelobes inthe mainlobe of matched filtered output, mathched filter is only considered; when thetime-bandwidth of LFM carrier is high enough to have some sidelobes in the mainlobe ofmatched filtered output, mismathched filter with the chebyshev window is applied. In addition,mismatched filter based on minimum peak sidelobe level is applied for pulse compression ofBarker code. The simulation results demonstrate the effectiveness of the proposed method.
3) A Barker coded excitation method with pseudo-chirp carrier is proposed. In contrast toconventional Barker coded excitation with sinusoidal carrier, the method can improve axialresolution and SNR. In contrast to the Barker coded excitation with LFM carrier, theexcitation signal in the proposed Barker coded excitation is binary, so the average power islarge, and the SNR is improved while maintaining almost same axial resolution and contrastresolution. In addition, the transmitter circuit is simple. The effectiveness of the proposedmethod is examined by simulations.
4) A Golay coded excitation method with LFM carrier is proposed. In comparison withconventional Golay coded excitation with sinusoidal carrier, the method uses LFM carrier, soit can improve axial resouliton and SNR. In comprarison with the Barker coded excitationusing LFM carrier, the method uses long-length Golay complementary sequences, so it canboost SNR and its gain, and achieve low level of range sidelobes to enhance contrastresolution while maintaining nearly same axial resolution. Matched filter is only considereredfor pulse compression of Golay complementary sequences and the pulse compression schemeis simple. The simulation results demonstrate the effectiveness of the proposed method.
5) An optimal binary coded excitation with LFM carrier is proposed. In contrast to theBarker coded excitation with LFM carrier, the method uses a long-length optimal binarysequence, so it can boost SNR and its gain while maintaining nearly same axial resolution. Incontrast to the Golay coded excitation with LFM carrier, the method has advantage of singletransmit, and has no problem with motion-dependant decoding error. Pulse compressionscheme is developed to ensure contrast resolution. Inverse filter based on minimum meansquare error is applied for pulse compression of optimal binary sequence to suppresssidelobes. The simulation results demonstrate the effectiveness of the proposed method.
1）为了提高轴向分辨力和确保对比度，提出了一种基于幅度加权的预失真线性调频编码激励方法。该方法将线性调频发射信号幅度加权技术和回波信号旁瓣抑制技术相结合，一方面补偿超声探头对发射信号的影响，使得回波信号的带宽不局限于探头，提高轴向分辨力；另一方面消除发射信号幅频特性的菲涅耳波纹，提高发射信号的带宽并采用失配滤波器进行脉冲压缩，实现旁瓣抑制，确保成像对比度。仿真结果表明，与恒包络的线性调频编码激励相比，该方法不仅可以提高轴向分辨力，而且确保对比度；在轴向分辨力和对比度两方面，取得较好的折中效果。FieldII仿真B超图像结果同样证实该方法提高轴向分辨力。
2）传统Barker编码激励是采用单载频的正弦信号调制Barker编码的。本文中，提出了一种基于线性调频载波调制的Barker编码激励方法。对比正弦载波，线性调频载波的时间-带宽积可以大于1。因此，该方法通过提高载波带宽，可以提高轴向分辨力；另一方面，通过提高单位码片时间（即载波时间宽度），可以提高系统的信噪比。此外，系统的信噪比增益不仅能通过Barker码长获得，还可以通过载波的时间-带宽积获得。为了确保成像对比度，在脉冲压缩时，首先进行线性调频载波的脉冲压缩，然后进行Barker编码的脉冲压缩，实现旁瓣抑制。对于线性调频载波的脉冲压缩，当载波的时间-带宽积较小时，确保匹配滤波输出的主瓣内无旁瓣，此时只需要考虑匹配滤波器；当载波的时间-带宽积较大时，使得匹配滤波输出的主瓣内有旁瓣，此时需要考虑加切比雪夫窗的失配滤波器。对于Barker编码的脉冲压缩，采用基于峰值旁瓣水平最小的失配滤波器。仿真结果证明了所提出方法的有效性。
3）提出了一种基于伪chirp载波调制的Barker编码激励方法。与传统的基于正弦载波调制的Barker编码激励相比，该方法采用伪chirp载波调制Barker编码，可以优化轴向分辨力和系统的信噪比。与基于线性调频载波调制的Barker编码激励相比，该方法的编码信号幅值是二进制形式的，平均功率大，从而提高系统的信噪比，同时保持相近的轴向分辨力和对比度，而且发射激励电路简单。仿真结果证明了所提出方法的有效性。
4）提出了一种基于线性调频载波调制的Golay编码激励方法。与传统的基于正弦载波调制的Golay编码激励相比，该方法采用线性调频载波调制Golay互补序列对，可以优化轴向分辨力和系统的信噪比。与基于线性调频载波调制的Barker编码激励相比，该方法采用增加长度的Golay互补序列对，可以获得更高的信噪比及其增益，而且旁瓣幅度大大降低，因而增强成像对比度，同时保持相近的轴向分辨力。在脉冲压缩滤波器的设计中，对于Golay编码的脉冲压缩，只需要考虑匹配滤波器，脉冲压缩算法简单。仿真结果证明了所提出方法的有效性。
5）提出了一种基于线性调频载波调制的二进制最优编码激励方法。与基于线性调频载波调制的Barker编码激励相比，该方法使用增加长度的二进制最优序列，可以获得更高的信噪比及其增益，同时保持相近的轴向分辨力。与基于线性调频载波调制的Golay编码激励相比，该方法只需要发射信号一次，脉冲压缩性能不易受组织运动的影响。在脉冲压缩滤波器的设计中，对于二进制最优序列的脉冲压缩，采用基于最小均方误差的逆滤波器，实现旁瓣抑制，确保成像对比度。仿真结果证明了所提出方法的有效性。
In medical ultrasound imaging system, axial resolution, signal-to-noise ratio (SNR orpenetration) and contrast resolution are crucial factors to consider in evalution of imagequality. The tradeoff between axial resolution and SNR is well-known in conventionalsingle-pulse ultrasound system. However, coded excitation technique can well circumvent thisproblem. Here the duration of the excitation signal can be increased while maintaining thepeak power. More acoustic energy can be transmitted, thereby increasing the SNR. Axialresolution is usually recovered by compressing the echo signal in the receiver. The codedexcitation technique has been suggested as an efficient means of improving the quality ofultrasound imaging, so it has a wide application prospect. Based on a deep study on therelated theory and existing algorithms, the dissertation has developed some new methods onthe coded excitation. The main contributions are as follows.
1) In order to improve axial resolution and satisfy contrast resolution of medicalultrasound imaging, a predistorted linear frequency modulated (LFM) coded excitationmethod based on amplitude weighting is proposed. Combining the amplitude weightingtechnology of LFM transmit signal with the sidelobe reduction technology of echo signal, themethod on the one hand can compensate the influence of transducer impulse response on thetransmit signal, so the bandwidth of echo signal is not limited by the transducer and the axialresolution is improved. On the other hand, the method can remove the Fresnel ripples of thetransmit signal’s frequency response, increase its bandwidth and use mismatched filter withthe chebyshev window for pulse compression, so range sidelobes are suppressed to ensure thecontrast resolution. The simulation results reveal that, in contrast to constant-envelope LFMcoded excitation, the proposed method can improve axial resolution and satisfy contrastresolution of medical imaging, and achieve good compromise between axial resolution andcontrast resolution. FieldII Simulation results of B-mode image show that the axial resolutionof the proposed method is improved.
2) Traditionally, a single-frequency sinusoidal signal is used as the carrier of Barkercoded excitation. A Barker coded excitation method with LFM carrier is proposed. Incomparison with sinusoidal carrier, LFM carrier has the time-bandwidth product on the orderof above one. Thus, the method can improve axial resolution by increasing the bandwidth ofLFM carrier. On the other hand, the method can improve SNR by increasing the chip duration of Barker code, which is as large as the duration of LFM carrier. Moreover, SNR gain can beachieved not only by the length of Barker code but also by the time-bandwidth product ofLFM carrier. In order to ensure contrast resolution of medical imaging, pulse compressionscheme is developed to suppress sidelobes. It consists of two pulse compression filters forboth LFM carrier and Barker code, successively. With regard to the pulse compression ofLFM carrier, when the time-bandwidth of LFM carrier is low enough to have no sidelobes inthe mainlobe of matched filtered output, mathched filter is only considered; when thetime-bandwidth of LFM carrier is high enough to have some sidelobes in the mainlobe ofmatched filtered output, mismathched filter with the chebyshev window is applied. In addition,mismatched filter based on minimum peak sidelobe level is applied for pulse compression ofBarker code. The simulation results demonstrate the effectiveness of the proposed method.
3) A Barker coded excitation method with pseudo-chirp carrier is proposed. In contrast toconventional Barker coded excitation with sinusoidal carrier, the method can improve axialresolution and SNR. In contrast to the Barker coded excitation with LFM carrier, theexcitation signal in the proposed Barker coded excitation is binary, so the average power islarge, and the SNR is improved while maintaining almost same axial resolution and contrastresolution. In addition, the transmitter circuit is simple. The effectiveness of the proposedmethod is examined by simulations.
4) A Golay coded excitation method with LFM carrier is proposed. In comparison withconventional Golay coded excitation with sinusoidal carrier, the method uses LFM carrier, soit can improve axial resouliton and SNR. In comprarison with the Barker coded excitationusing LFM carrier, the method uses long-length Golay complementary sequences, so it canboost SNR and its gain, and achieve low level of range sidelobes to enhance contrastresolution while maintaining nearly same axial resolution. Matched filter is only considereredfor pulse compression of Golay complementary sequences and the pulse compression schemeis simple. The simulation results demonstrate the effectiveness of the proposed method.
5) An optimal binary coded excitation with LFM carrier is proposed. In contrast to theBarker coded excitation with LFM carrier, the method uses a long-length optimal binarysequence, so it can boost SNR and its gain while maintaining nearly same axial resolution. Incontrast to the Golay coded excitation with LFM carrier, the method has advantage of singletransmit, and has no problem with motion-dependant decoding error. Pulse compressionscheme is developed to ensure contrast resolution. Inverse filter based on minimum meansquare error is applied for pulse compression of optimal binary sequence to suppresssidelobes. The simulation results demonstrate the effectiveness of the proposed method.
引文
[1]周永昌,郭万学.超声医学[M].第四版.北京:科学技术文献出版社,2002.
[2]周康源.生物医学超声工程[M].四川:四川教育出版社,1991.
[3]伍于添.医学超声设备——原理.设计.应用[M].北京:科学技术文献出版社,2012.
[4]冯若.超声诊断设备原理与设计[M].北京:中国医药科技出版社,1993.
[5]王智标,李发琦,冯若,等.治疗超声原理与应用[M].南京:南京大学出版社,2008.
[6]冯若.超声空化与超声治疗[J].自然杂志,2004,25(6):311-314.
[7]王威琪,汪源源,余建国.诊断用医学超声学的现状[J].声学技术,2002,21(1-2):4-14.
[8]伍于添.超声诊断方法和设备的前沿技术[J].中国超声医学杂志,2004,20(6):470-475.
[9]杜宏伟.生物医学超声中若干非线性问题的研究[D].合肥:中国科学技术大学,2007.
[10]鲍静.医学超声成像系统的编码激励技术研究[D].天津:天津大学,2007.
[11]彭虎.超声成像算法导论[M].合肥:中国科学技术大学出版社,2008.
[12]舒贞权.医学超声影像新技术综述[J].中国医疗器械信息,2002,8(2):9-14.
[13]龚秀芬.医学超声中的声学非线性研究[J].物理学进展,1996,16(3~4):286-298.
[14]Lencioni R, Cioni D, Bartolozzi C. Tissue harmonic and contrast-specific imaging: backto gray scale in ultrasound [J]. European Radiology,2002,12(1):151-165.
[15]Frinking P. J. A, Bouakaz A, Kirkhorn J, et al. Ultrasound contrast imaging: current andnew potential methods [J]. Ultrasound in Medicine and Biology,2000,26(6):965-975.
[16]余薇,胡佑伦,刘昌慧.医学超声成像技术方法学进展[J].北京生物医学工程,2001,20(3):225-228.
[17]王艳丹,高上凯.超声成像新技术及其临床应用[J].北京生物医学工程,2006,25(5):553-555.
[18]Averkiou M. A, Roundhill D. N, Powers J. E. A new imaging technique based on thenonlinear properties of tissues [A]. in Proc. Ultrasonics Symposium [C]. Toronto, Ont:IEEE,1997:1561-1566.
[19]金树武.现代医学超声诊断仪新技术发展特点[J].世界医疗器械,2001,7(11):14-17.
[20]Ophir J, Alam S. K, Garra B. S, et al. Elastography: imaging the elastic properties of softtissues with ultrasound [J]. Journal of Medical Ultrasonics,2002,29(4):155-171.
[21]Konofagou E, Ophir J. A new elastographic method for estimation and imaging of lateraldisplacements, lateral strains, corrected axial strains and poisson’s ratios in tissues [J].Ultrasound in Medicine and Biology,1998,24(8):1183-1199.
[22]徐智章,俞清.超声弹性成像原理及初步应用[J].上海医学影像,2005,14(1):3-5.
[23]Fenster A, Downey D. B.3-D Ultrasound imaging: a review [J]. IEEE Engineering inMedicine and Biology Magazine,1996,15(6):41-51.
[24]Karadayi K, Managuli R, Kim Y. Three-dimensional ultrasound: from acquisition tovisualization and from algorithms to systems [J]. IEEE Reviews in BiomedicalEngineering,2009,2:23-39.
[25]AIU-NEMA. Safety standard for diagnostic ultrasound equipment. J Ultrasound Med,1983.
[26]冯若.超声手册[M]].南京:南京大学出版社,2002.
[27]O’Donnell M. Coded excitation system for improving the penetration of real-timephased-array imaging systems [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, andFrequency Control,1992,39(3):341-351.
[28]Chiao R. Y, Hao X. Code excitation for diagnostic ultrasound: a system developer’sperspective [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control,2005,52(2):160-170.
[29]彭旗宇,高上凯.医学超声成像中的编码激励技术及其应用[J].生物医学工程学杂志,2005,22(1):175-180.
[30]Brookner E. Phased-array radars [J]. Scientific American,1985,52(2):96-98.
[31]Cook C. E. The early history of pulse compression radar [J]. IEEE Transactions onAerospace and Electronic Systems,1988,24(6):825-833.
[32]Bendick P. J, Newhouse V. L. Ultrasonic random-signal flow measurement system [J].Acoustical Society of America,1974,56:860-870.
[33]周奇.高频超声编码激励系统研究与设计[D].北京:中国医学科学院,2009.
[34]张香林.超声成像中编码激励方法的研究[D].吉林:吉林大学,2011.
[35]毕然.超声成像系统中编码激励和脉冲压缩技术的研究和应用[D].哈尔滨:哈尔滨工业大学,2010.
[36]Newhouse V. L, Cathignol D, Chapelon J. Y. Introduction to ultrasonic pseudo-randomcode system [J]. Progress in Medical Imaging,1988:215-226.
[37]Chapelon J. Y. Pseudo-random correlation imaging and system characterization [J].Progress in Medical Imaging,1988:227-246.
[38]Chapelon J. Y, Cathignol D, Fourcade C. Improved ultrasonic sensitivity usingpseudo-random binary-code phased-modulated signals [J]. Ultrasonic Imaging,1979,1(3):255-264.
[39]Takeuchi Y. An investigation of a spread energy method for medical ultrasound systems:part one: theory and investigation [J]. Ultrasonics,1979,17(4):175-182.
[40]Misaridis T. X, Jensen J. A. Use of modulated excitation signals in medical ultrasound,part I: basic concepts and expected benefits [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,2005,52(2):177-191.
[41]彭珏,覃正迪,刁现芬,等.医学超声关键技术研究和进展,(一):超声换能器与超声编码技术[J].生物医学工程学进展,2013,34(1):21-27.
[42]Li P.-C, Ebbini E., O’Donnell M.. A new filter design technique for coded excitationsystems [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control,1992,39(6):693-699.
[43]Jeng G. S, Huang S, Li P.-C, et al. A novel pulse compression technique using inversefiltering in frequency domain [A]. in Proc. IEEE Ultrasonics Symposium [C]. Atlanta,GA. Oct2001,2:1535-1538.
[44]Wilhjelm J. E, Pedersen P. C. Target velocity estimation with FM and PW echo rangingDoppler systems. I. signal analysis [J]. IEEE Transactions on Ultrasonics, Ferroelectrics,and Frequency Control,1993,40(4):366-372.
[45]Wilhjelm J. E, Pedersen P. C. Target velocity estimation with FM and PW echo rangingDoppler systems. II. systems analysis [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,1993,40(4):373-380.
[46]Rao N. A. H. K. Investigation of a pulse compression technique for medical ultrasound: asimulation study [J]. Medical and Biological Engineering and Computing,1994,32(2):181-188.
[47]Takeuchi Y. Chirped excitation for <-100dB time sidelobe echo sounding [A]. in Proc.Ultrasonics Symposium [C]. Seattle, WA: IEEE,1995:1309-1314.
[48]Misaridis T. X, Jensen J. A. An effective coded excitation scheme based on a predistortedFM signal and an optimized digital filter [A]. in Proc. Ultrasonics Symposium [C].Caesars Tahoe, NV: IEEE,1999:1589-1593.
[49]Misaridis T. X, Gammelmark K, Jorgensen C. H, et al. Potential of coded excitation inmedical ultrasound imaging [J]. Ultrasonics,2000,38(1-8):183-189.
[50]Pedersen M. H, Misaridis T. X, Jensen J. A. Clinical comparison of pulse and Chirpexcitation [A]. in Proc. IEEE Ultrasonics Symposium [C].2002:1673-1676.
[51]Behar V, Adam D. Parameter optimization of pulse compression in ultrasound imagingsystems with coded excitation [J]. Ultrasonics,2004,42(10):1101-1109.
[52]Misaridis T. X, Jensen J.A. Use of modulated excitation signals in medical ultrasound,part II: design and performance for medical imaging applications [J]. IEEE Transactionson Ultrasonics, Ferroelectrics, and Frequency Control,2005,52(2):191-206.
[53]Raman R, Rao N. Pre-enhancement of chirp signal for inverse filtering in medicalultrasound [A]. in Proc. Engineering in Medicine and Biology Society [C]. Baltimore,MD: IEEE,1994:676-677.
[54]Venkatraman S, Rao N. A. H. K. Combining pulse compression and adaptive drive signaldesign to inverse filter the transducer system response and improve resolution in medicalultrasound [J]. Medical and Biological Engineering and Computing,1996,34(4):318-320.
[55]Barros A. L. P, Machado J. C, da Costa-Felix R. P. B. A frequency-compensatedcoded-excitation pulse to improve axial resolution of ultrasonic system [A]. in Proc.Ultrasonics Symposium [C]. Vancouver, BC: IEEE.2006:1651-1654.
[56]Oelze M. L. Improved axial resolution using pre-enhanced chirps and pulse compression[A]. in Proc. Ultrasonics Symposium [C]. Vancouver, BC: IEEE,2006:1083-1086.
[57]Oelze M. L. Bandwidth and resolution enhancement through pulse compression [J]. IEEETransactions on Ultrasonics, Ferroelectrics, and Frequency Control,2007,54(4):768-781.
[58]Park J, Hu C. H, Wu D. W, et al. Compensation of the transducer response for highfrequency coded excitation imaging[A]. in Proc. Ultrasonics Symposium [C]. Rome:IEEE,2009:2312-2315.
[59]胡伟,郭建中.基于LFM脉冲压缩编码技术的超声成像[J].声学技术,2012,31(4):307-309.
[60]Cheng J, Chen S. P. A modified LFM signal in coded ultrasound [A]. in Proc.International Seminar on Future BioMedical Information Engineering [C]. Wuhan, Hubei,2008:389-391.
[61]Kowatsch M, Stocker H. R. Effect of Fresnel ripples on sidelobe suppression in lowtime-bandwidth product linear FM pulse compression [J]. Communications, Radar andSignal Processing,1982,129(1):41-44.
[62]Cowe J, Gittins J, Evans D. H. Improving performance of pulse compression in a Dopplerultrasound system using amplitude modulated chirps and Wiener filtering [J]. Ultrasoundin Medicine and Biology,2008,34(2):326-333.
[63]Sanchez J. R, Oelze M. A spatially varying pulse compression filter for coded excitationsignals [A]. in Proc. Ultrasonics Symposium [C]. San Diego, CA: IEEE,2010:371-374.
[64]Brenner A. R, Eck K, Wilhelm W, et al. Improved resolution and dynamic range inmedical ultrasonic imaging using depth dependent mismatched filter [A]. in Proc.Ultrasonics Symposium [C]. Toronto, Ont: IEEE,1997:1475-1480.
[65]Eck K, Schwann R, Brenner A. R, et al. Depth-dependent mismatched filtering usingultrasonic attenuation as a filter design parameter [A]. in Proc. Ultrasonics Symposium[C]. Sendai: IEEE,1998:1639-1644.
[66]Pollakowski M, Ermert H. Chirp signal matching and signal power optimization inpulse-echo mode ultrasonic nondestructive testing [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,1994,41(5):655-659.
[67]Gran F, Jensen J. A. Designing non-linear frequency modulated signals for medicalultrasound imaging [A]. in Proc. Ultrasonics Symposium [C]. Vancouver, BC: IEEE,2006:1714-1717.
[68]Golay M. J. E. Complementary series [J]. IRE Transactions on Information Theory,1961,7(2):82-87.
[69]Yoo Y. M, Lee W. Y, Song T. K. A low voltage portable system using modified Golaysequences [A]. in Proc. Ultrasonics Symposium [C]. Atlanta, GA: IEEE,2001:1469-1472.
[70]周盛,王晓春,杨军,等.医学高频超声编码成像中解码压缩技术的研究[J].中国医疗器械杂志,2011,35(6):409-413.
[71]Trots I, Nowicki A, Secomski W, et al. Transducer bandwidth influence on the Golayencoded ultrasound echoes [A]. in Proc. Ultrasonics Symposium [C]. New York, NY:IEEE,2007:1274-1277.
[72]Leavens C, Willams R, Burns P, et al. The use of phase codes in ultrasound imaging: SNRgain and bandwidth requirements [J]. Applied Acoustics,2009,70(10):1340-1351.
[73]Haider B, Lewin P. A, Thomenius K. E. Pulse elongation and deconvolution filtering formedical ultrasonic imaging [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, andFrequency Control,1998,45(1):98-113.
[74]Zhao H, Gao S. K. Barker-coded ultrasound color flow imaging: theoretical and practicaldesign considerations [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, andFrequency Control,2007,54(2):319-331.
[75]Wang Y, Metzger K, Stephens D. N, et al. Coded excitation with spectrum inversion(CEXSI) for ultrasound array imaging [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,2003,50(7):805-823.
[76]Hu C. H, Liu R, Zhou Q. F, et al. Coded excitation using biphase-coded pulse withmismatched filters for high-frequency ultrasound imaging [J]. Ultrasonics,2006,44(3):330-336.
[77]刘波,郭建中.载频调制二相编码激励的超声成像信噪比提高研究[J].电子学报,2011,39(11):2701-2707.
[78]Rihaczek A. W, Golden R. M. Range sidelobe suppression for Barker codes [J]. IEEETransaction on Aerospace and Electronic Systems,1971, AES-7(6):1087-1092.
[79]Mosca E. Sidelobe reduction in phase-coded pulse compression radar [J]. IEEETransaction on Information Theory,1967,13(1):131-134.
[80]Levanon N. Cross-correlation of long binary signals with longer mismatched filters [J].Radar, Sonar and Navigation,2005,152(6):377-382
[81]Asafusa K, Azuma T, Shinomura R, et al. Ultrasound imaging system usingcombinational coded excitation [A]. in Proc. IEEE Ultrasonics Symposium [C].2004:2045-2048.
[82]Shen J, Ebbini E. S. A new coded-excitation ultrasound imaging system. I. Basicprinciples [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control,1996,43(1):131-140.
[83]Kazys R, Svilainis L, Mazeika L. Application of orthogonal ultrasonic signals andbinaural processing for imaging of the environment [J]. Ultrasonics,2000,38(1-8):171-175.
[84]Polpetta A, Banelli P. Huffman sequence design for coded excitation in medicalultrasound [A]. in Proc. Ultrasonics Symposium [C]. Rome: IEEE,2009:2386-2389.
[85]Polpetta A, Banelli P. Design and performance of Huffman sequences in medicalultrasound coded excitation [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, andFrequency Control,2012,59(4):630-647.
[86]Qin Z. D, Chen S. P, Chen X. Coded transmission for ultrasound Doppler detection usingtruncated long code sequence [A]. in Proc. Biomedical Engineering and Informatics [C].Yantai.2010:159-161.
[87]Qin Z. D, Liu D. Q, Chen S. P. Experimental study on the truncated long code sequencefor ultrasound Doppler detection [A]. in Proc. Biomedical Engineering and Informatics
[C]. Chongqing.2012:50-52.
[88]Ruprecht J, Rupf M. On the search for good aperiodic binary invertible sequences [J].IEEE Transactions on Information Theory,1996,42(5):1604-1612.
[89]刘凯,高上凯.编码激励超声成像系统中二进制最优编码序列的研究[J].中国生物医学工程学报,2007,26(1):42-47.
[90]Liu K, Gao S. K. Searching binary sequences for coded excitation in medical ultrasound[A]. in Proc. Engineering in Medicine and Biology Society [C]. Shanghai: IEEE,2006:1858-1860.
[91]周浩,王友钊,郑音飞.医学超声编码激励技术研究进展[J].浙江大学学报:工学版,2011,45(2):387-391.
[92]Misaridis T. X, Pedersen M. H, Jensen J. A. Clinical use and evaluation of codedexcitation in B-mode images [A]. in Proc. Ultrasonics Symposium [C]. San Juan:IEEE,2000:1689-1693.
[93]赵衍.超声彩色血流成像中编码激励技术的研究[D].北京:清华大学,2006.
[94]赵衍,高上凯.超声二进制编码激励血流测量的实验研究[J].中国生物医学工程学报,2001,26(1):12-18.
[95]Xiang L, Zhao H, Gao S. K. Barker code in TCD ultrasound systems to improve thesensitivity of emboli detection [J]. Ultrasound in Medicine and Biology,2009,35(1):94-101.
[96]Gran F, Udesen J, Nielsen M, et al. Coded ultrasound for blood flow estimation usingsubband processing [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and FrequencyControl,2008,55(10):2211-2220.
[97]Lamboul B, Bennett M, Anderson T, et al. Basic considerations in the use of codedexcitation for color flow imaging applications [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,2009,56(4):727-737.
[98]Chiao R. Y, Mo L. Y, Hall A. L, et al. B-mode blood flow (B-Flow) imaging [A]. in Proc.Ultrasonics Symposium [C]. San Juan: IEEE,2000:1469-1472.
[99]Misaridis T. X, Jensen J. A. Space-time encoding for high frame rate ultrasound imaging[J]. Ultrasonics,2002,40(1-8):593-597.
[100] Misaridis T. X, Jensen J. A. Use of modulated excitation signals in medical ultrasound.Part III: High frame rate imaging [J]. IEEE Transactions on Ultrasonics, Ferroelectrics,and Frequency Control,2005,52(2):207-218.
[101] Jin C, Chen S. P, Qin Z. D. A new coding scheme in coded ultrasound using staggeringrepetition interval [J]. Journal of Zhejiang University Science A,2009,10(8):1213-1216.
[102]彭虎,陆建宇,张作生,等.高帧率超声成像系统中提高信噪比的一种方法[J].北京生物医学工程,2003,22(3):164-167.
[103]韩雪梅,彭虎,杜宏伟,等.基于线性调频信号的高帧率超声成像系统[J].中国生物医学工程学报,2005,24(6):700-704.
[104]韩雪梅,彭虎,蔡波.基于线性调频信号的高帧率超声成像系统的改进[J].生物医学工程学杂志,2009,26(4):761-765.
[105]郑驰超,彭虎.基于编码发射与自适应波束形成的超声成像[J].电子与信息学报,2010,32(4):959-962.
[106] Jensen J. A, Holm O, Jerisen L. J, et al. Ultrasound research scanner for real-timesynthetic aperture data acquisition [J]. IEEE Transactions on Ultrasonics, Ferroelectrics,and Frequency Control,2005,52(5):881-891.
[107] Chiao R. Y, Thomas L. J. Synthetic transmit aperture imaging using orthogonal Golaycoded excitation [A]. in Proc. Ultrasonics Symposium [C]. San Juan: IEEE,2000:1677-1680.
[108] Huang S. W, Li P. C. Binary code design for high-frequency ultrasound [J]. IEEETransactions on Ultrasonics, Ferroelectrics, and Frequency Control,2007,54(5):947-956.
[109] Mamou J, Ketterling J. A, Silverman R. H. Chirp-coded excitation imaging with ahigh-frequency ultrasound annular array [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,2008,55(2):508-513.
[110] Park J, Hu C. H, Li X, et al. Wideband linear power amplifier for high-frequencyultrasonic coded excitation imaging [J]. IEEE Transactions on Ultrasonics, Ferroelectrics,and Frequency Control,2012,59(4):825-832.
[111] Zhou S, Wang X. C, Ye Q. S, et al. Medical high-frequency ultrasound imaging usingGolay-coded pulse excitation [A]. in Proc. Biomedical Engineering and Informatics [C].Chongqing.2012:71-75.
[112]刘凯,高上凯.高频超声成像中的编码激励研究[J].北京生物医学工程,2007,26(1):31-35.
[113]周盛,王晓春,计建军,等. Barker编码激励在眼科高频超声成像中的应用研究[J].中国生物医学工程学报,2012,31(5):671-678.
[114] Chen X, Zhou H, Wen S, et al. Increasing average power in medical ultrasonicendoscope imaging system by coded excitation [A]. in Proc. Optical Instruments andTechnology: Optical systems and Optoelectronic Instruments [C]. Beijing.2008(doi:10.1117/12.807063).
[115] Takeuchi Y. Coded excitation for harmonics imaging [A]. in Proc. IEEE UltrasonicsSymposium [C].1996:1433-1436.
[116] Kim D. Y, Lee J. C, Kwon S. J, et al. Ultrasound second harmonic imaging with aweighted chirp signal [A]. in Proc. Ultrasonics Symposium [C]. Atlanta, GA: IEEE,2001:1477-1480.
[117] Arshadi R, Yu A. C. H, Cobbold R. S. C. Coded excitation methods for ultrasoundharmonic imaging [J]. Canadian Acoustics,2007,35(2):35-46.
[118] Song J, Kim S, Sohn H, et al. Coded excitation for ultrasound tissue harmonic imaging[J]. Ultrasonics,2010,50(6):613-619.
[119] Song J, Chang J. H, Song T, et al. Coded tissue harmonic imaging with nonlinear chirpsignals [J]. Ultrasonics,2011,51(4):516-521.
[120] Shen C. C, Shi T. Y. Third harmonic transmit phasing for SNR improvement in tissueharmonic imaging with Golay-encoded excitation [J]. Ultrasonics,2011,51(5):554-560.
[121] Borsboom J, Chin C. T, de Jong N. Experimental validation of a nonlinear codedexcitation method for contrast imaging [A]. in Proc. IEEE Ultrasonics Symposium [C].2002:1729-1731.
[122] Borsboom J. M. G, Chin C. T, Bouakaz A, et al. Harmonic chirp imaging method forultrasound contrast agent [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, andFrequency Control,2005,52(2):241-249.
[123]谷金宏,万明习,王素品,等.基于调频信号发射的超声造影剂谐波成像方法[J].声学学报,2006,31(3):240-246.
[124] Liu J, Insana M. F. Coded pulsed excitation for ultrasonic strain imaging [J]. IEEETransactions on Ultrasonics, Ferroelectrics, and Frequency Control,2005,52(2):231-240.
[125]彭辉,刘东权. Chirp编码激励在超声弹性成像系统中的应用研究[J].中国生物医学工程学报,2011,30(4):514-519.
[126]张晗.基于编码激励和脉冲压缩的深层介质超声弹性成像信噪比与分辨率提高[D].西安:陕西师范大学,2012.
[127] Peng H, Liu D. C. Enhanced ultrasound strain imaging using chirp-coded pulseexcitation [J]. Biomedical signal processing and control,2013,8(2):130-141.
[128] Sanchez J, Oelze M. An ultrasonic imaging speckle-suppression andcontrast-enhancement technique by means of frequency compounding and codedexcitation [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control,2009,56(7):1327-1339.
[129] Nowicki A, Litniewski J, Secomski W, et al. Estimation of ultrasonic attenuation in abone using coded excitation [J]. Ultrasonics,2003,41(8):615-621.
[130]蒲诚,张涛,吕方.编码激励超声流量测量平台[J].传感器与微系统,2009,28(10):85-90.
[131] Jensen J. A. Field: a program for simulating ultrasound systems [A]. in Proc.Biomedical Imaging [C]. Tampere: Citeseer.1996:351-355.
[132] Barker R. H. Communication Theory [M]. New York: Jackson W,1953.
[133] Muzilla D. J, Chiao R. Y, Hall A. L. Method and apparatus for color flow imaging usingcoded excitation with single codes [P]. U. S. Patent:5,938,611,1999.
[134] Mo L. Y. L, Ji T. L, Chou C. H, et al. Zone-based color flow imaging [A]. in Proc. IEEEUltrasonics Symposium [C].2003:29-32.
[135]项雷,高上凯.编码激励在脉冲Doppler超声血流测量中的应用[J].清华大学学报，2008,48(6):1032-1035.
[136] Welch L. R, Fox M. D. Practical spread spectrum pulse compression for ultrasonictissue imaging [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and FrequencyControl,1998,45(2):349-355.
[2]周康源.生物医学超声工程[M].四川:四川教育出版社,1991.
[3]伍于添.医学超声设备——原理.设计.应用[M].北京:科学技术文献出版社,2012.
[4]冯若.超声诊断设备原理与设计[M].北京:中国医药科技出版社,1993.
[5]王智标,李发琦,冯若,等.治疗超声原理与应用[M].南京:南京大学出版社,2008.
[6]冯若.超声空化与超声治疗[J].自然杂志,2004,25(6):311-314.
[7]王威琪,汪源源,余建国.诊断用医学超声学的现状[J].声学技术,2002,21(1-2):4-14.
[8]伍于添.超声诊断方法和设备的前沿技术[J].中国超声医学杂志,2004,20(6):470-475.
[9]杜宏伟.生物医学超声中若干非线性问题的研究[D].合肥:中国科学技术大学,2007.
[10]鲍静.医学超声成像系统的编码激励技术研究[D].天津:天津大学,2007.
[11]彭虎.超声成像算法导论[M].合肥:中国科学技术大学出版社,2008.
[12]舒贞权.医学超声影像新技术综述[J].中国医疗器械信息,2002,8(2):9-14.
[13]龚秀芬.医学超声中的声学非线性研究[J].物理学进展,1996,16(3~4):286-298.
[14]Lencioni R, Cioni D, Bartolozzi C. Tissue harmonic and contrast-specific imaging: backto gray scale in ultrasound [J]. European Radiology,2002,12(1):151-165.
[15]Frinking P. J. A, Bouakaz A, Kirkhorn J, et al. Ultrasound contrast imaging: current andnew potential methods [J]. Ultrasound in Medicine and Biology,2000,26(6):965-975.
[16]余薇,胡佑伦,刘昌慧.医学超声成像技术方法学进展[J].北京生物医学工程,2001,20(3):225-228.
[17]王艳丹,高上凯.超声成像新技术及其临床应用[J].北京生物医学工程,2006,25(5):553-555.
[18]Averkiou M. A, Roundhill D. N, Powers J. E. A new imaging technique based on thenonlinear properties of tissues [A]. in Proc. Ultrasonics Symposium [C]. Toronto, Ont:IEEE,1997:1561-1566.
[19]金树武.现代医学超声诊断仪新技术发展特点[J].世界医疗器械,2001,7(11):14-17.
[20]Ophir J, Alam S. K, Garra B. S, et al. Elastography: imaging the elastic properties of softtissues with ultrasound [J]. Journal of Medical Ultrasonics,2002,29(4):155-171.
[21]Konofagou E, Ophir J. A new elastographic method for estimation and imaging of lateraldisplacements, lateral strains, corrected axial strains and poisson’s ratios in tissues [J].Ultrasound in Medicine and Biology,1998,24(8):1183-1199.
[22]徐智章,俞清.超声弹性成像原理及初步应用[J].上海医学影像,2005,14(1):3-5.
[23]Fenster A, Downey D. B.3-D Ultrasound imaging: a review [J]. IEEE Engineering inMedicine and Biology Magazine,1996,15(6):41-51.
[24]Karadayi K, Managuli R, Kim Y. Three-dimensional ultrasound: from acquisition tovisualization and from algorithms to systems [J]. IEEE Reviews in BiomedicalEngineering,2009,2:23-39.
[25]AIU-NEMA. Safety standard for diagnostic ultrasound equipment. J Ultrasound Med,1983.
[26]冯若.超声手册[M]].南京:南京大学出版社,2002.
[27]O’Donnell M. Coded excitation system for improving the penetration of real-timephased-array imaging systems [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, andFrequency Control,1992,39(3):341-351.
[28]Chiao R. Y, Hao X. Code excitation for diagnostic ultrasound: a system developer’sperspective [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control,2005,52(2):160-170.
[29]彭旗宇,高上凯.医学超声成像中的编码激励技术及其应用[J].生物医学工程学杂志,2005,22(1):175-180.
[30]Brookner E. Phased-array radars [J]. Scientific American,1985,52(2):96-98.
[31]Cook C. E. The early history of pulse compression radar [J]. IEEE Transactions onAerospace and Electronic Systems,1988,24(6):825-833.
[32]Bendick P. J, Newhouse V. L. Ultrasonic random-signal flow measurement system [J].Acoustical Society of America,1974,56:860-870.
[33]周奇.高频超声编码激励系统研究与设计[D].北京:中国医学科学院,2009.
[34]张香林.超声成像中编码激励方法的研究[D].吉林:吉林大学,2011.
[35]毕然.超声成像系统中编码激励和脉冲压缩技术的研究和应用[D].哈尔滨:哈尔滨工业大学,2010.
[36]Newhouse V. L, Cathignol D, Chapelon J. Y. Introduction to ultrasonic pseudo-randomcode system [J]. Progress in Medical Imaging,1988:215-226.
[37]Chapelon J. Y. Pseudo-random correlation imaging and system characterization [J].Progress in Medical Imaging,1988:227-246.
[38]Chapelon J. Y, Cathignol D, Fourcade C. Improved ultrasonic sensitivity usingpseudo-random binary-code phased-modulated signals [J]. Ultrasonic Imaging,1979,1(3):255-264.
[39]Takeuchi Y. An investigation of a spread energy method for medical ultrasound systems:part one: theory and investigation [J]. Ultrasonics,1979,17(4):175-182.
[40]Misaridis T. X, Jensen J. A. Use of modulated excitation signals in medical ultrasound,part I: basic concepts and expected benefits [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,2005,52(2):177-191.
[41]彭珏,覃正迪,刁现芬,等.医学超声关键技术研究和进展,(一):超声换能器与超声编码技术[J].生物医学工程学进展,2013,34(1):21-27.
[42]Li P.-C, Ebbini E., O’Donnell M.. A new filter design technique for coded excitationsystems [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control,1992,39(6):693-699.
[43]Jeng G. S, Huang S, Li P.-C, et al. A novel pulse compression technique using inversefiltering in frequency domain [A]. in Proc. IEEE Ultrasonics Symposium [C]. Atlanta,GA. Oct2001,2:1535-1538.
[44]Wilhjelm J. E, Pedersen P. C. Target velocity estimation with FM and PW echo rangingDoppler systems. I. signal analysis [J]. IEEE Transactions on Ultrasonics, Ferroelectrics,and Frequency Control,1993,40(4):366-372.
[45]Wilhjelm J. E, Pedersen P. C. Target velocity estimation with FM and PW echo rangingDoppler systems. II. systems analysis [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,1993,40(4):373-380.
[46]Rao N. A. H. K. Investigation of a pulse compression technique for medical ultrasound: asimulation study [J]. Medical and Biological Engineering and Computing,1994,32(2):181-188.
[47]Takeuchi Y. Chirped excitation for <-100dB time sidelobe echo sounding [A]. in Proc.Ultrasonics Symposium [C]. Seattle, WA: IEEE,1995:1309-1314.
[48]Misaridis T. X, Jensen J. A. An effective coded excitation scheme based on a predistortedFM signal and an optimized digital filter [A]. in Proc. Ultrasonics Symposium [C].Caesars Tahoe, NV: IEEE,1999:1589-1593.
[49]Misaridis T. X, Gammelmark K, Jorgensen C. H, et al. Potential of coded excitation inmedical ultrasound imaging [J]. Ultrasonics,2000,38(1-8):183-189.
[50]Pedersen M. H, Misaridis T. X, Jensen J. A. Clinical comparison of pulse and Chirpexcitation [A]. in Proc. IEEE Ultrasonics Symposium [C].2002:1673-1676.
[51]Behar V, Adam D. Parameter optimization of pulse compression in ultrasound imagingsystems with coded excitation [J]. Ultrasonics,2004,42(10):1101-1109.
[52]Misaridis T. X, Jensen J.A. Use of modulated excitation signals in medical ultrasound,part II: design and performance for medical imaging applications [J]. IEEE Transactionson Ultrasonics, Ferroelectrics, and Frequency Control,2005,52(2):191-206.
[53]Raman R, Rao N. Pre-enhancement of chirp signal for inverse filtering in medicalultrasound [A]. in Proc. Engineering in Medicine and Biology Society [C]. Baltimore,MD: IEEE,1994:676-677.
[54]Venkatraman S, Rao N. A. H. K. Combining pulse compression and adaptive drive signaldesign to inverse filter the transducer system response and improve resolution in medicalultrasound [J]. Medical and Biological Engineering and Computing,1996,34(4):318-320.
[55]Barros A. L. P, Machado J. C, da Costa-Felix R. P. B. A frequency-compensatedcoded-excitation pulse to improve axial resolution of ultrasonic system [A]. in Proc.Ultrasonics Symposium [C]. Vancouver, BC: IEEE.2006:1651-1654.
[56]Oelze M. L. Improved axial resolution using pre-enhanced chirps and pulse compression[A]. in Proc. Ultrasonics Symposium [C]. Vancouver, BC: IEEE,2006:1083-1086.
[57]Oelze M. L. Bandwidth and resolution enhancement through pulse compression [J]. IEEETransactions on Ultrasonics, Ferroelectrics, and Frequency Control,2007,54(4):768-781.
[58]Park J, Hu C. H, Wu D. W, et al. Compensation of the transducer response for highfrequency coded excitation imaging[A]. in Proc. Ultrasonics Symposium [C]. Rome:IEEE,2009:2312-2315.
[59]胡伟,郭建中.基于LFM脉冲压缩编码技术的超声成像[J].声学技术,2012,31(4):307-309.
[60]Cheng J, Chen S. P. A modified LFM signal in coded ultrasound [A]. in Proc.International Seminar on Future BioMedical Information Engineering [C]. Wuhan, Hubei,2008:389-391.
[61]Kowatsch M, Stocker H. R. Effect of Fresnel ripples on sidelobe suppression in lowtime-bandwidth product linear FM pulse compression [J]. Communications, Radar andSignal Processing,1982,129(1):41-44.
[62]Cowe J, Gittins J, Evans D. H. Improving performance of pulse compression in a Dopplerultrasound system using amplitude modulated chirps and Wiener filtering [J]. Ultrasoundin Medicine and Biology,2008,34(2):326-333.
[63]Sanchez J. R, Oelze M. A spatially varying pulse compression filter for coded excitationsignals [A]. in Proc. Ultrasonics Symposium [C]. San Diego, CA: IEEE,2010:371-374.
[64]Brenner A. R, Eck K, Wilhelm W, et al. Improved resolution and dynamic range inmedical ultrasonic imaging using depth dependent mismatched filter [A]. in Proc.Ultrasonics Symposium [C]. Toronto, Ont: IEEE,1997:1475-1480.
[65]Eck K, Schwann R, Brenner A. R, et al. Depth-dependent mismatched filtering usingultrasonic attenuation as a filter design parameter [A]. in Proc. Ultrasonics Symposium[C]. Sendai: IEEE,1998:1639-1644.
[66]Pollakowski M, Ermert H. Chirp signal matching and signal power optimization inpulse-echo mode ultrasonic nondestructive testing [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,1994,41(5):655-659.
[67]Gran F, Jensen J. A. Designing non-linear frequency modulated signals for medicalultrasound imaging [A]. in Proc. Ultrasonics Symposium [C]. Vancouver, BC: IEEE,2006:1714-1717.
[68]Golay M. J. E. Complementary series [J]. IRE Transactions on Information Theory,1961,7(2):82-87.
[69]Yoo Y. M, Lee W. Y, Song T. K. A low voltage portable system using modified Golaysequences [A]. in Proc. Ultrasonics Symposium [C]. Atlanta, GA: IEEE,2001:1469-1472.
[70]周盛,王晓春,杨军,等.医学高频超声编码成像中解码压缩技术的研究[J].中国医疗器械杂志,2011,35(6):409-413.
[71]Trots I, Nowicki A, Secomski W, et al. Transducer bandwidth influence on the Golayencoded ultrasound echoes [A]. in Proc. Ultrasonics Symposium [C]. New York, NY:IEEE,2007:1274-1277.
[72]Leavens C, Willams R, Burns P, et al. The use of phase codes in ultrasound imaging: SNRgain and bandwidth requirements [J]. Applied Acoustics,2009,70(10):1340-1351.
[73]Haider B, Lewin P. A, Thomenius K. E. Pulse elongation and deconvolution filtering formedical ultrasonic imaging [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, andFrequency Control,1998,45(1):98-113.
[74]Zhao H, Gao S. K. Barker-coded ultrasound color flow imaging: theoretical and practicaldesign considerations [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, andFrequency Control,2007,54(2):319-331.
[75]Wang Y, Metzger K, Stephens D. N, et al. Coded excitation with spectrum inversion(CEXSI) for ultrasound array imaging [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,2003,50(7):805-823.
[76]Hu C. H, Liu R, Zhou Q. F, et al. Coded excitation using biphase-coded pulse withmismatched filters for high-frequency ultrasound imaging [J]. Ultrasonics,2006,44(3):330-336.
[77]刘波,郭建中.载频调制二相编码激励的超声成像信噪比提高研究[J].电子学报,2011,39(11):2701-2707.
[78]Rihaczek A. W, Golden R. M. Range sidelobe suppression for Barker codes [J]. IEEETransaction on Aerospace and Electronic Systems,1971, AES-7(6):1087-1092.
[79]Mosca E. Sidelobe reduction in phase-coded pulse compression radar [J]. IEEETransaction on Information Theory,1967,13(1):131-134.
[80]Levanon N. Cross-correlation of long binary signals with longer mismatched filters [J].Radar, Sonar and Navigation,2005,152(6):377-382
[81]Asafusa K, Azuma T, Shinomura R, et al. Ultrasound imaging system usingcombinational coded excitation [A]. in Proc. IEEE Ultrasonics Symposium [C].2004:2045-2048.
[82]Shen J, Ebbini E. S. A new coded-excitation ultrasound imaging system. I. Basicprinciples [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control,1996,43(1):131-140.
[83]Kazys R, Svilainis L, Mazeika L. Application of orthogonal ultrasonic signals andbinaural processing for imaging of the environment [J]. Ultrasonics,2000,38(1-8):171-175.
[84]Polpetta A, Banelli P. Huffman sequence design for coded excitation in medicalultrasound [A]. in Proc. Ultrasonics Symposium [C]. Rome: IEEE,2009:2386-2389.
[85]Polpetta A, Banelli P. Design and performance of Huffman sequences in medicalultrasound coded excitation [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, andFrequency Control,2012,59(4):630-647.
[86]Qin Z. D, Chen S. P, Chen X. Coded transmission for ultrasound Doppler detection usingtruncated long code sequence [A]. in Proc. Biomedical Engineering and Informatics [C].Yantai.2010:159-161.
[87]Qin Z. D, Liu D. Q, Chen S. P. Experimental study on the truncated long code sequencefor ultrasound Doppler detection [A]. in Proc. Biomedical Engineering and Informatics
[C]. Chongqing.2012:50-52.
[88]Ruprecht J, Rupf M. On the search for good aperiodic binary invertible sequences [J].IEEE Transactions on Information Theory,1996,42(5):1604-1612.
[89]刘凯,高上凯.编码激励超声成像系统中二进制最优编码序列的研究[J].中国生物医学工程学报,2007,26(1):42-47.
[90]Liu K, Gao S. K. Searching binary sequences for coded excitation in medical ultrasound[A]. in Proc. Engineering in Medicine and Biology Society [C]. Shanghai: IEEE,2006:1858-1860.
[91]周浩,王友钊,郑音飞.医学超声编码激励技术研究进展[J].浙江大学学报:工学版,2011,45(2):387-391.
[92]Misaridis T. X, Pedersen M. H, Jensen J. A. Clinical use and evaluation of codedexcitation in B-mode images [A]. in Proc. Ultrasonics Symposium [C]. San Juan:IEEE,2000:1689-1693.
[93]赵衍.超声彩色血流成像中编码激励技术的研究[D].北京:清华大学,2006.
[94]赵衍,高上凯.超声二进制编码激励血流测量的实验研究[J].中国生物医学工程学报,2001,26(1):12-18.
[95]Xiang L, Zhao H, Gao S. K. Barker code in TCD ultrasound systems to improve thesensitivity of emboli detection [J]. Ultrasound in Medicine and Biology,2009,35(1):94-101.
[96]Gran F, Udesen J, Nielsen M, et al. Coded ultrasound for blood flow estimation usingsubband processing [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and FrequencyControl,2008,55(10):2211-2220.
[97]Lamboul B, Bennett M, Anderson T, et al. Basic considerations in the use of codedexcitation for color flow imaging applications [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,2009,56(4):727-737.
[98]Chiao R. Y, Mo L. Y, Hall A. L, et al. B-mode blood flow (B-Flow) imaging [A]. in Proc.Ultrasonics Symposium [C]. San Juan: IEEE,2000:1469-1472.
[99]Misaridis T. X, Jensen J. A. Space-time encoding for high frame rate ultrasound imaging[J]. Ultrasonics,2002,40(1-8):593-597.
[100] Misaridis T. X, Jensen J. A. Use of modulated excitation signals in medical ultrasound.Part III: High frame rate imaging [J]. IEEE Transactions on Ultrasonics, Ferroelectrics,and Frequency Control,2005,52(2):207-218.
[101] Jin C, Chen S. P, Qin Z. D. A new coding scheme in coded ultrasound using staggeringrepetition interval [J]. Journal of Zhejiang University Science A,2009,10(8):1213-1216.
[102]彭虎,陆建宇,张作生,等.高帧率超声成像系统中提高信噪比的一种方法[J].北京生物医学工程,2003,22(3):164-167.
[103]韩雪梅,彭虎,杜宏伟,等.基于线性调频信号的高帧率超声成像系统[J].中国生物医学工程学报,2005,24(6):700-704.
[104]韩雪梅,彭虎,蔡波.基于线性调频信号的高帧率超声成像系统的改进[J].生物医学工程学杂志,2009,26(4):761-765.
[105]郑驰超,彭虎.基于编码发射与自适应波束形成的超声成像[J].电子与信息学报,2010,32(4):959-962.
[106] Jensen J. A, Holm O, Jerisen L. J, et al. Ultrasound research scanner for real-timesynthetic aperture data acquisition [J]. IEEE Transactions on Ultrasonics, Ferroelectrics,and Frequency Control,2005,52(5):881-891.
[107] Chiao R. Y, Thomas L. J. Synthetic transmit aperture imaging using orthogonal Golaycoded excitation [A]. in Proc. Ultrasonics Symposium [C]. San Juan: IEEE,2000:1677-1680.
[108] Huang S. W, Li P. C. Binary code design for high-frequency ultrasound [J]. IEEETransactions on Ultrasonics, Ferroelectrics, and Frequency Control,2007,54(5):947-956.
[109] Mamou J, Ketterling J. A, Silverman R. H. Chirp-coded excitation imaging with ahigh-frequency ultrasound annular array [J]. IEEE Transactions on Ultrasonics,Ferroelectrics, and Frequency Control,2008,55(2):508-513.
[110] Park J, Hu C. H, Li X, et al. Wideband linear power amplifier for high-frequencyultrasonic coded excitation imaging [J]. IEEE Transactions on Ultrasonics, Ferroelectrics,and Frequency Control,2012,59(4):825-832.
[111] Zhou S, Wang X. C, Ye Q. S, et al. Medical high-frequency ultrasound imaging usingGolay-coded pulse excitation [A]. in Proc. Biomedical Engineering and Informatics [C].Chongqing.2012:71-75.
[112]刘凯,高上凯.高频超声成像中的编码激励研究[J].北京生物医学工程,2007,26(1):31-35.
[113]周盛,王晓春,计建军,等. Barker编码激励在眼科高频超声成像中的应用研究[J].中国生物医学工程学报,2012,31(5):671-678.
[114] Chen X, Zhou H, Wen S, et al. Increasing average power in medical ultrasonicendoscope imaging system by coded excitation [A]. in Proc. Optical Instruments andTechnology: Optical systems and Optoelectronic Instruments [C]. Beijing.2008(doi:10.1117/12.807063).
[115] Takeuchi Y. Coded excitation for harmonics imaging [A]. in Proc. IEEE UltrasonicsSymposium [C].1996:1433-1436.
[116] Kim D. Y, Lee J. C, Kwon S. J, et al. Ultrasound second harmonic imaging with aweighted chirp signal [A]. in Proc. Ultrasonics Symposium [C]. Atlanta, GA: IEEE,2001:1477-1480.
[117] Arshadi R, Yu A. C. H, Cobbold R. S. C. Coded excitation methods for ultrasoundharmonic imaging [J]. Canadian Acoustics,2007,35(2):35-46.
[118] Song J, Kim S, Sohn H, et al. Coded excitation for ultrasound tissue harmonic imaging[J]. Ultrasonics,2010,50(6):613-619.
[119] Song J, Chang J. H, Song T, et al. Coded tissue harmonic imaging with nonlinear chirpsignals [J]. Ultrasonics,2011,51(4):516-521.
[120] Shen C. C, Shi T. Y. Third harmonic transmit phasing for SNR improvement in tissueharmonic imaging with Golay-encoded excitation [J]. Ultrasonics,2011,51(5):554-560.
[121] Borsboom J, Chin C. T, de Jong N. Experimental validation of a nonlinear codedexcitation method for contrast imaging [A]. in Proc. IEEE Ultrasonics Symposium [C].2002:1729-1731.
[122] Borsboom J. M. G, Chin C. T, Bouakaz A, et al. Harmonic chirp imaging method forultrasound contrast agent [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, andFrequency Control,2005,52(2):241-249.
[123]谷金宏,万明习,王素品,等.基于调频信号发射的超声造影剂谐波成像方法[J].声学学报,2006,31(3):240-246.
[124] Liu J, Insana M. F. Coded pulsed excitation for ultrasonic strain imaging [J]. IEEETransactions on Ultrasonics, Ferroelectrics, and Frequency Control,2005,52(2):231-240.
[125]彭辉,刘东权. Chirp编码激励在超声弹性成像系统中的应用研究[J].中国生物医学工程学报,2011,30(4):514-519.
[126]张晗.基于编码激励和脉冲压缩的深层介质超声弹性成像信噪比与分辨率提高[D].西安:陕西师范大学,2012.
[127] Peng H, Liu D. C. Enhanced ultrasound strain imaging using chirp-coded pulseexcitation [J]. Biomedical signal processing and control,2013,8(2):130-141.
[128] Sanchez J, Oelze M. An ultrasonic imaging speckle-suppression andcontrast-enhancement technique by means of frequency compounding and codedexcitation [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control,2009,56(7):1327-1339.
[129] Nowicki A, Litniewski J, Secomski W, et al. Estimation of ultrasonic attenuation in abone using coded excitation [J]. Ultrasonics,2003,41(8):615-621.
[130]蒲诚,张涛,吕方.编码激励超声流量测量平台[J].传感器与微系统,2009,28(10):85-90.
[131] Jensen J. A. Field: a program for simulating ultrasound systems [A]. in Proc.Biomedical Imaging [C]. Tampere: Citeseer.1996:351-355.
[132] Barker R. H. Communication Theory [M]. New York: Jackson W,1953.
[133] Muzilla D. J, Chiao R. Y, Hall A. L. Method and apparatus for color flow imaging usingcoded excitation with single codes [P]. U. S. Patent:5,938,611,1999.
[134] Mo L. Y. L, Ji T. L, Chou C. H, et al. Zone-based color flow imaging [A]. in Proc. IEEEUltrasonics Symposium [C].2003:29-32.
[135]项雷,高上凯.编码激励在脉冲Doppler超声血流测量中的应用[J].清华大学学报，2008,48(6):1032-1035.
[136] Welch L. R, Fox M. D. Practical spread spectrum pulse compression for ultrasonictissue imaging [J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and FrequencyControl,1998,45(2):349-355.