Equipment Teraherz measuring station

The THz-CW system is intended to enable measurements in the frequency range from 100 GHz to 2.7 THz. It consists of tunable lasers based on DFB lasers with wavelengths in the range around 1.5um, photoconductive mixers, optical and mechanical components for beam guidance and central control for operation and data acquisition.

The THz-TDS system uses a femtosecond pulse laser to generate broadband teraheart signals. The conversion of the optical fiber-bound excitation into a terahertz signal radiated into free space is carried out with 2 independent semiconductor emitters with linearly polarized antennas. The detection of the terahertz signals is carried out with 2 independent semiconductor receivers, also with linearly polarized antennas. In addition to the necessary optical components for signal distribution and delay, a 2-D raster unit and a

The system contains all the necessary optical and mechanical components for immediate operational readiness.

Vector network analysis between 330 GHz and 750 GHz requires both a vector network analyzer (VNA) as a base device with a minimum frequency of 26 GHz and the corresponding frequency extender modules for the frequency range from 330 GHz to 500 GHz and 500 GHz to 750 GHz.

Planned measurements include at least the complete, vectorial 2-port S-parameter measurement with two TxRx frequency extender modules and the antenna measurement described below. For antenna measurements, a pure Rx frequency extender module is also required, which can be mounted on our robot. That's why this Rx frequency extender module has high demands on compactness (limited volume) and mass.

Due to the frequent measurements with a free-space measurement component (antenna measurement and quasi-optical measurements), the highest possible dynamics are very important. Accordingly, the phase noise of the VNA should be as low as possible. In addition, there must be an input for an external hardware trigger for the antenna measurement on the VNA. A software trigger is not enough.

For certain measurement objects, the output power of the TxRx frequency extender modules must be known as precisely as possible or be able to be calibrated. This means that it must be possible to measure it as accurately as possible with a power sensor that is not part of the tender. For power measurement, it is therefore important that the output signal of the TxRx frequency extender module contains as few unwanted harmonics as possible (due to frequency multiplication). Thus, the lowest possible multiplication factor of the TxRx frequency extender module is very advantageous.

In addition, it would be desirable to characterize complex components or radar systems with a freely selectable modulation signal, i.e. that the VNA should offer the option to modulate a source analog and / or digital. In terms of the compactness of the overall structure, an internal source has advantages over corresponding interfaces for external source injection into the VNA.

To perform complex MMIC characterizations, at least three independent low-noise sources are required (number of RF sources plus LO sources equal to 3).