基于漂移阶跃恢复二极管的超宽带探地雷达发射技术

Transmitter techniques for ultra-wideband ground penetrating radar based on drift step recovery diodes

在概述高功率半导体开关漂移阶跃恢复二极管(DSRD)的性能特点、工作原理的基础上,详细阐述了其快恢复物理特性的机理,并论证了快恢复过程需满足的条件。结合DSRD快速关断特性与电容电感储能特性,通过复杂可编程逻辑器件产生外触发时序控制信号,设计了一款质量轻(小于1.5 kg)、体积小(13cm×9 cm×8 cm)、性能稳定可靠(抖动小于1%)的高压窄脉冲超宽带雷达发射机。实验结果表明,单管电路所产生的脉冲幅度可达1 kV,半脉宽小于10 ns,重复频率高于10 kHz,可应用于超宽带无载波脉冲探地雷达系统中。

Based on summarizing the characteristics and working principle of high power semiconductor switching drift step recovery diodes（DSRD）, the physical mechanism of fast recovery is explained in detail and the necessary conditions of fast recovery are also demonstrated. An ultra-wideband radar transmitter was designed with light weight （less than 1.5 kg）, small size（13 cm×9 cm×8 cm） and simple structure. It utilizes DSRD＇s fast switching characteristic combined with the procedure of capacitor and inductor collecting energy to generate high-voltage and narrow-width pulses, and adopts complex programmable logic device （CPLD） to generate timing logic control trigger pulses. Experimental results show that the pulse generator with one DSRD can generate pulses with amplitude of 1 kV, half-width less than 10 ns and repetition rate higher than 10 kHz, which can be applied in impulse ground penetrating radar systems.