心内传导通信调制方案分析

Analysis of Intracardiac Conduction Communication Modulation Scheme

目的:电流耦合心内传导通信(conductive intracardiac communication,CIC)方式已被证明适用于多腔无导线心脏起搏器(Leadless Cardiac Pacemaker,LCP)的同步。本文基于自主设计的电流耦合CIC收发器分析调制方式和信道长度(10mm-110mm)对收发器性能的影响。方法:以FPGA为平台,结合外围电路设计出可实现OOK和CPFSK两种调制方式的电流耦合CIC收发器。通过离体猪心实验,检测所设计收发器的通信性能,并探究信道长度对收发器性能的影响。结果:实验表明,采用简单的调制技术,在较低的传输功耗下实现LCP是可行的;两种调制方式的传输误码率均处于较低水平(<2.80×10^(-5));在该信道长度内误码率波动明显,最大差值达100倍;OOK方式随信道长度的变化趋势比CPFSK方式更平缓。结论:OOK方式用于心内传导通信时准确性良好并具有更高的稳定性。

Purpose:The galvanic coupled conductive intracardiac communication(CIC)method has been shown to be suitable for synchronizing multi-chamber leadless cardiac pacemakers(LCP).Based on a uniquely designed galvanic CIC transceiver,the effect of modulation method and channel length(10mm-110mm)on the performance of the transceiver is analyzed in this work.Methods:A galvanic coupled CIC transceiver with two modulation methods,OOK and CPFSK,was designed using an FPGA as the platform and peripheral circuits.The communication performance of the designed transceiver was tested by in virto porcine heart experiments,and the effect of channel length on the performance of the transceiver was investigated.Results:The experiments show that it is feasible to achieve LCP at low transmission power consumption using elementary modulation techniques;the transmission bit error rate(BER)of both modulation methods is at a low level(<2.80×10^(-5));the BER fluctuates significantly within this channel length,with a maximum difference of 100 times;the trend of the OOK method with channel length is smoother than that of the CPFSK method.Conclusion:The OOK method has good accuracy and higher stability when used for intra-body communication.