SoC-Based Automated Diagnostic Instrument for FMCW Reflectometry Applications

Abstract

This article discusses the design and development of a compact frequency modulated continuous wave (FMCW) Reflectometry diagnostic instrument. The existing setup is rigid and bulky utilizing precious Tokamak lab space, lack of remote configurability option, and requires manual intervention to change control parameters. Hence, we propose a system-on-chip ( ${\textit {SoC}} $ )-based automated reflectometry diagnostic instrument $\textit {(ARDI)} $ to implement all the four major electronic components into a single instrument. Wherein, the analog driver is designed to generate a non-linear sweep voltage of 0–20 V in order to drive the ultrawideband voltage controlled oscillator ( ${\textit {VCO}} $ ). The data acquisition system (DAQ) is deployed to acquire the in-phase ( ${I} $ ) and quadrature ( ${Q} $ ) components of a signal at 245 mega samples per second (MSPS) with 14-bit resolution. The trigger unit operating in pattern mode at 100 MHz is responsible to trigger all the units synchronously. The data processing unit , normalizes the signal using the proposed hardware accelerator clocked at 200 MHz. The proposed normalization technique is analyzed and compared with envelope-based normalization technique. This study conveys that the proposed technique utilizes lesser hardware resources with the availability of both ${I} $ and ${Q} $ components, making it computationally simpler and faster. The designed ARDI can be configured and monitored remotely by developing a graphical user interface ( ${\textit {GUI}} $ ).