便携式时域反射仪硬件系统设计  

Hardware design of a portable time domain reflectometry

作　　者：沈绍祥[1,2] 冯炜[1,2] 纪奕才[1] 方广有[1] 

机构地区：[1]中国科学院电子学研究所,北京100190 [2]中国科学院研究生院,北京100190

出　　处：《电子技术应用》2010年第1期75-78,共4页Application of Electronic Technique

摘　　要：介绍了用于土壤参数测量的时域反射仪硬件系统的设计与实现方案,并研制出样机TDR-I。该样机使用DSP做主控板,利用阶跃恢复二极管(SRD)产生140ps上升沿的快沿发射脉冲,采用快慢斜波比较法获得等效采样步进精度为8.7ps的取样脉冲。经过实验数据获取验证,该系统测量效果良好。Hardware design of a portable time domain reflectometry（TDR） is introduced in this paper. This TDR can be applied to test soil parameters. A prototype of TDR-I has been developed, in which a DSP board is used as the main control unit. A 140 ps rising edge transmit pulse is generated by step recovery diode. The precision of step pulse is achieved to be 8.7 ps by equivalent sampling based on the comparison of fast ramp and slow ramp. The experimental results verified the good performance of the system.

关 键 词：时域反射仪 等效采样 步进脉冲 采样门 

分 类 号：TM930.111[电气工程—电力电子与电力传动]