Dr. Gregory L. Charvat

FMCW Radar

A Unique Approach to Frequency Modulated Continuous Wave (FMCW) Radar

This is my masters thesis at the Michigan State University Electromagnetics Research Group.

  • An unusual approach to FMCW radar
  • Utilizing two Gunnplexer, Gunn diode based transmit/receive modules
  • Shown to be useful for ranging and doppler
  • Shown to be capable of SAR imaging
  • Developed as part of a low-cost proof-of-concept radar system
  • Applications might include automotive radar, motion detection, etc.


Frequency-Modulated Continuous-Wave (FMCW) Radar has traditionally been used in short range applications. Conventional FMCW radar requires the use of expensive microwave mixers and low noise amplifiers. A uniquely inexpensive solution was created, using inexpensive Gunn oscillator based microwave transceiver modules that consist of 3 diodes inside of a resonant cavity. However these transceiver modules have stability problems which cause them to be unsuitable for use in precise FMCW radar applications, when just one module is used. In order to overcome this problem, a unique radar solution was developed which uses a combination of 2 transceiver modules to create a precise FMCW radar system. This unique solution to FMCW radar is proven to be capable of determining range to target, and creating Synthetic Aperture Radar images.

The Unique Approach to FMCW Radar Hardware

The following are pictures of the hardware systems developed for this research effort. Extensive use of surplus and recycled electronics are shown here:

Range Profile Results Using the Unique Approach to FMCW Radar

The following are range profiles acquired by using the unique approach to FMCW radar.

SAR Imaging Using a Unique Approach to FMCW Radar

Synthetic Aperture Radar (SAR) imaging results using the unique approach to FMCW radar. Shown below is the experimental setup and resulting SAR imagery using a number of different SAR imaging algorithms.