为了实现无线健康监测,人体通信技术发展迅速。然而,人体是电磁波信号传输的障碍物,盲目增大电磁波辐射场不利于人体安全。长期临床应用证明超声在人体组织的穿透性能优于电磁波且对人体无害。但现有二维模型在仿真人体内信号传输多径效应上受限。为此提出按照人体组织的层次结构建立三维人体模型,用K空间方法解决了传统方法中模型复杂度高的问题,提高了仿真速度和仿真效率。通过仿真对比实验,测试不同类型的信号、不同信号频率和不同人体组织的传输特性,找到了应对人体信道多径效应和高衰减问题的通信方法,最终对体内跨组织传输场景进行仿真。结果表明,600KHz的调相信号可实现跨越不同人体组织的信号传输,利用超声实现人体通信是安全可行的。
Human body area network technology has developed rapidly for the need in wireless heath monitoring. But the human body becomes the obstacle of electromagnetic wave signal transmission. Increasing the power of electromagnetic wave blindly is not conducive to the human body safety. Traditional wireless communication technology has suffered limitations. Long term clinical application shows that the ultrasonic in human tissue penetration perform- ance is better than that of electromagnetic wave but harmless to human body. According to the hierarchy of human tis- sue, a 3D human body model is built to fit the multipath problem of signal transmission in the human body. The K - Space method is used to solve the problem of high complexity of the traditional methods of model and to improve the simulation speed and simulation efficiency. The characteristic of the signal transformed in different body tissue and different frequency is tested through the simulations. The methods to deal with the body channel muhipath effect and high attenuation problem of communication are found. Finally, a cross tissue situation signal transformation simulation is performed. The result shows that the 600KHz phase modulated signal transformed from the fat layer to the surface of skin has a good performance. It shows that using ultrasonic in human body communication can be available and safety.