This article presents a novel development of a very high-frequency (VHF) lightning interferometer system at National Atmospheric Research Laboratory, Gadanki (13.58°E,79.18°N). While similar systems have been developed in the past, this system distinguishes itself due to use of PXIe-based commercial-off-the-shelf (COTS) digitizers and controllers, offering the ease of configuration, scalability, and future upgradability. The system design comprises three broadband RF channels, a trigger generator, and a high-speed digitizer. The RF frontend incorporates discone antennas, bandpass filters, and low-noise amplifiers, ensuring efficient capture of lightning signals in the 20–80-MHz frequency band. The system addresses issues encountered during initial field experiments, such as frequent amplifier failures, by implementing voltage regulation closer to the amplifier. The signal acquisition system utilizes modular PXIe-based technology, enabling high bandwidth and throughput. The system employs two dual-channel Keysight M9203A PXIe digitizer cards mounted in a Keysight M9019A chassis, along with an embedded controller (Keysight M9037A) for seamless control and data acquisition. Its design and scalable architecture hold promise for future enhancements and upgrades. An example observation of a lightning flash recorded during the initial field deployment is presented. The detailed analysis of the flash showcases system’s capabilities in capturing the initiation, progression, and branching of lightning channels and identifying initial breakdown pulses (IBPs) and their characteristics.

中文翻译：

---

基于 PXIe 的 VHF 闪电干涉仪系统的设计和初步观测

本文介绍了Gadanki（13.58°E，79.18°N）国家大气研究实验室的甚高频（VHF）闪电干涉仪系统的新颖开发。虽然过去已经开发过类似的系统，但该系统的独特之处在于使用基于 PXIe 的商用现成 (COTS) 数字化仪和控制器，提供了易于配置、可扩展性和未来可升级性。该系统设计包括三个宽带射频通道、一个触发发生器和一个高速数字转换器。 RF 前端包含盘锥天线、带通滤波器和低噪声放大器，确保有效捕获 20–80 MHz 频段的闪电信号。该系统通过在靠近放大器的地方实施电压调节，解决了初始现场实验期间遇到的问题，例如放大器频繁故障。该信号采集系统采用基于 PXIe 的模块化技术，可实现高带宽和吞吐量。该系统采用安装在 Keysight M9019A 机箱中的两个双通道 Keysight M9203A PXIe 数字化仪卡以及用于无缝控制和数据采集的嵌入式控制器 (Keysight M9037A)。其设计和可扩展架构为未来的增强和升级带来了希望。介绍了在初始现场部署期间记录的闪电观测的示例。对闪电的详细分析展示了系统捕获闪电通道的启动、进展和分支以及识别初始击穿脉冲 (IBP) 及其特征的能力。