High temperature S-parameter imaging is a radio frequency measurement technique used to determine the material properties of a sample at elevated temperatures. In this technique, a vector network analyzer (VNA) is used to measure the reflection and transmission coefficients (S-parameters) of the sample over a range of frequencies, while the sample is heated to a high temperature.

To perform high temperature S-parameter imaging, a high temperature furnace is used to heat the sample while it is placed in the near-field of a probing antenna that is connected to the VNA. The VNA then measures the S-parameters of the sample at each frequency in the desired frequency range while the sample is at the elevated temperature. This process is repeated at multiple locations on the sample surface to create an image of the material properties across the surface at high temperatures.

The resulting S-parameter image can be used to extract various material properties of the sample, such as its dielectric constant and conductivity, at high temperatures. These properties are important in many high-temperature applications, such as furnace linings, turbine engines, and rocket propulsion systems.