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The detectors based on superconductors are used for the registration of signals in the millimeter range [1]. Specially, the quantum radio receptor is widely used due to its very high sensibility. The structure of such receptor consists usually of a periodic Josephson’s Junctions (JJs) lattice and its very high sensibility may be obtained with the synchronization of the JJs using resonators of superficial electromagnetic wave [2]. These resonators realize automatically the synchronization of several hundreds of JJs, including the electro dynamical especial line like lattice [2].

Volume and based on surface oriented integrated p-i-n-structures modulators have demonstrated high efficiency in millimeter wave range as quasi-optical modulators and phase shifters. These structures possess high modulation and high-speed properties; sustain great EM powers. However, the modulation characteristics of p-i-n modulators of both mentioned types in millimeter wave range have not been investigated yet. Here, a comparison and criteria of volume and integrated based on Si surface oriented structure modulators in millimeter wave range are presented.

This paper is focused on the choice of the module for low noise receiver in millimeter (mm) and sub millimeter (submm) wave ranges used in geophysical remote sensing systems for measurement of geophysical parameters by means of radiobrightness temperatures (radiometer systems obtaining data by means of radiobrightness temperatures). The observed data analysis, used in order to obtain recommendations and forecasts based on the radio telescope measurements and geophysical phenomena in the events of earthquakes, volcano explosions and typhoons, are realized by means of specialized computer codes.

The superheterodyne amplification of sub-millimeter electromagnetic waves in GasAs due to negative differential mobility is analyzed. The nonlinearity arises from the current and the magnetic field of the electromagnetic waves. The case of interaction of two traveling counter propagating electromagnetic waves and the following space charge wave in an n-GaAs film, placed onto i-GaAs substrate, is considered, under a 2D electron gas model. The simulation of this nonlinear interaction shows a certain amplification of the sub-millimeter electromagnetic wave.

This paper deals, at first, with the non-linear parametric effects on both space charge and electromagnetic waves in GaAs semiconductors. If an external electric field is applied, at the critical field value, the mobility changes its sign and becomes negative, as a result, non-linear instabilities of the interactions are obtained. At the optimal value of electric field, Eopt, all non-linear processes are very effectives. The second point is the multiplication of the wave frequency, which is also effective thanks to the non-linearity. This process is used for carring waves into millimeter range instead of generation process, which in this range is non-effective. The Multiplication effect is based on the using space charge waves.