Example of VNA


Frequency-domain vector reflectometer
•THz extension of vector network analyzer
•Sweeps in frequency, power, time
•Both CW and pulsed modes of operation
•Up to 140 dB dynamic range
•Intermediate frequency 1 Hz – 18 MHz
•Quasiopticsetup for complex reflection coefficient measurement

VNA with THz extension components.

Operational bands of THz extenders.

Quasiopticsetup for reflection measurements.

Reflectivity of water/glycerol mixture with PMMA antireflection layer.

Complex reflection coefficient of silicon sample.

Dielectric function calculated from reflection data.

Application example

Water is known for its high THz attenuation coefficient due to the Debye relaxation and can be used as an efficient absorber if the reflection from the surface is eliminated. By using a layer of PMMA and refractive index matching with a water/glycerol mixture a very efficient absorber was constructed for 240 GHz radiation


1. M.L.P. Bailey, A.T. Pierce, A.J. Simon, D.T. Edwards, G.J. Ramian, and M.S. Sherwin “Frequency-domain vector reflectometry” in preparation.