基于PDChirp-Golay信号的编码激励算法

线性调频信号编码激励超声成像算法旁瓣过高，针对这个问题，提出一种基于幅度加权的预失真线性调频信号调制Golay码(PDChirp-Golay)编码新方法.该方法将线性调频发射信号采用预失真处理，可以补偿超声探头对发射信号的影响，使回波信号的带宽增大，提高轴向分辨力，并同时消除发射信号幅频特性的菲涅耳波纹，实现旁瓣抑制;之后使用预失真处理的线性调频发射信号调制Golay码.Golay码理论上距离旁瓣水平为零，可以利用Golay码这一特点进一步进行旁瓣抑制.仿真结果表明，相较于单独的预失真线性调频信号与Golay码，预失真Chirp信号调制的Golay码提高了轴向分辨力和对比度，并且具有很好的抗噪性，为实现高质量的超声成像系统提供了理论依据.

Coding Incentive Algorithm Based on PDChirp-Golay Signal

To solve the problem of high sidelobe in ultrasonic imaging algorithms induced by LFM signal coding， a new method of PDChirp-Golay coding based on amplitude weighting is proposed. This method predistorts linear frequency modulation(LFM) signals， thus compensating the influence of ultrasonic probe on the emission signal， which makes the bandwidth of the echo signal increase， improves the axial resolution， and eliminates the Fresnel corrugation of the emission signal amplitude frequency characteristics at the same time， realizing sidelobe suppression. Then， the predistorted LFM signal is used to modulate Golay code. The range sidelobe level of Golay code is zero in theory， which makes the sidelobe further suppressed. The simulation results show that， compared with the single predistorted LFM signal and Golay code， Golay code modulated by the predistorted Chirp signal improves the axial resolution and contrast， and has a good anti-noise performance， which provides a theoretical basis for the realization of high-quality ultrasonic imaging system.