针对腹主动脉瘤腔内修复手术后内漏检测困难的问题,设计了一种基于感容(LC)压力传感器的无线血压测量系统。采用现场可编程门阵列(FPGA)芯片作为主控制单元,利用读取线圈与传感器之间的耦合作用实现传感器信号的无线测量。基于直接频率合成技术的正弦扫频信号发生器产生驱动信号,基于互相关算法的离散傅立叶变换计算信号频谱,两者的结合有效提高了系统的测量精度和速度。实验结果表明:系统的测量压力分辨率和测量速度分别为285 Pa和24.1 Hz,为血压的无线测量提供了一种有效方法。
In order to solve endoleak emerged after endovascular aneurysm repair, a wireless blood pressure measuring system based on LC pressure sensor is designed. A chip based on field programmable gate array (FPGA) is used as main processing unit and wireless measurement is realized using mutual coupling effect between the reader coil and the sensor. A sine signal generator based on direct digital frequency synthesis technology is used to generate driving signals and discrete Fourier transform based on cross-correlation algorithm is used to calculate frequency spectrum of signals. The combination of them improves precision and speed effectively. Experimental results demonstrate that the resolution and the speed of the system is 285 Pa and 24. 1 Hz respectively, meaning that a new approach to measure blood pressure non-invasively is realized.