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After a brief presentation of the first vector measurements ever performed up to the THz with coherent sources, which were using BWOs and an interferometric technique, the possibility to use solid-state components is described. It involves frequency multiplication in Schottky harmonic generators as sources, and frequency downconversion in Schottky harmonic mixers as detectors. Instead of an interferometric setup, or instead of a second detection in a reference branch parallel to the DUT (Device Under Test) branch, like it is operated in classical millimeter network analyzers, the phase acquisition is purely electronic, which presents several advantages. The configurations of the analyzer without extensions are described. This section contains the choice of the harmonic order, the crosstalk effects and how to cancel them, and the dual-sense detection configuration, in which the microwave propagates, at the same time, in two directions. The interest of the latest configuration is when testing a given Schottky device in both harmonic generation (source) and harmonic mixing (detection) roles at the same time. The 4S-parameter configuration is shown. The 2S-parameter configuration is a simplified arrangement. The principle of phase acquisition does not involve any absolute frequency stabilization, since it is only the difference between two microwave sources which is stabilized. However some experiments need very stable and pure microwaves, which can be done. The analyzer can work at two frequencies at the same time. A description of several possible extensions of the analyzer is included. When a very large dynamic range is needed, one can associate with the analyzer a source which can remain free-running. When associating a Gunn oscillator feeding a multiharmonic harmonic generator, one can cover the frequencies up to 500 GHz. When associating two Gunn oscillators, the first followed by a multiharmonic harmonic generator, the second feeding a harmonic mixer, one can cover frequencies up to 1000 GHz. This setup can also work at two frequencies at the same time.
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