伪随机编码调制线性调频波的MIMO超声测量方法

MIMO ultrasonic measurement of pseudo-random code linear frequency modulation waveforms

结合稀疏阵元阵列MIMO成像方法和通信中的码分多址技术,提出一种采用平衡Gold伪随机码调制线性调频波(平衡Gold-LFM)发射的MIMO超声测量方法。通过优化设计传感器阵列,使多个阵元同时发射、多个阵元同时接收,接收的信号经过通道分离后进行波束形成。仿真实验表明平衡Gold-LFM复合信号具有较好的相关性,有利于回波信号的通道分离和测量准确性的提高。进一步仿真的统计表明:平衡Gold-LFM复合信号MIMO超声测量方法的测量误差在0.08mm范围内波动,同时在信噪比低至-30dB的条件下仍能可靠工作。这些仿真证实所提超声测量方法不仅可行,并能够进一步提高测量准确度。

In combining with the sparse transducer arrays in MIMO imaging and code division multiple access technology,an MIMO ultrasonic measurement is proposed based ultrasonic range detection with the composed signal of balance Gold phase coded signal and linear frequency modulation waveforms （Gold-LFM）.By optimizing the design of transducer arrays,the multiple ultrasonic transmit array elements can emit signal and other ultrasonic receive elements can receive echo simultaneously.The received signals are treated through channel separation to carry out the beamforming.The results from the simulation experiment show that the balance Gold-LFM composite waveforms have better correlation performance,which is benefit for channel separation of echo signal and improving the accuracy of measurement.The statistical analysis of further simulation indicates that measurement error of balance Gold-LFM waveforms excitation mode is about 0.08 mm.And the proposed ultrasonic measurement can still work reliably in low SNR of-30 dB.The simulations prove that the proposed ultrasonic measurement is not only feasible but also able to further improve measurement accuracy.