Using Simulations and Computational Analyses to Study a Frequency-Modulated Continuous-Wave Radar

This paper describes a method for simulating Frequency-Modulated Continuous-Wave (FMCW) radar. The developments presented target classroom lectures and can form the basis of student projects. Computational analysis and simulation are critical elements of science and engineering education in which students need to acquire these competencies. FMCW radar system simulations are an example of a real-world application, invested in rich mathematical/physical content that exercise these competencies. Unlike conventional radars that operate in the time domain, FMCW radars operate in the frequency domain. Spectral and phase analyses are required to infer range and the range resolved velocity of meteorological targets such as rain or drizzle. Hence to proceed with simulations, students are first introduced to signals processing topics such as discretization and sampling of signals, Fourier Transforms, Z-transforms, and filters. Computations and the display of results are subsequently performed using Elanix System Vue and Matlab software. To aid the interpretation of the results, a brief description of FMCW physical principles of operation is provided. The computational technique is general and efficient, allowing the range-resolved radial velocity component of precipitation to be computed in real-time. Simulations of range are in excellent agreement with field test measurements of experimental, operational X-band radar currently being evaluated at NASA Goddard Spaceflight Center while computations of the range-resolved velocity component of precipitation agree with the setup conditions of the simulations.