The structure of measuring stands of ultra-high-frequency installation of drying and baking of bricks is considered. The creation of a practical microwave installation is determined by the creation of measuring stands at a low power level, by working on electrodynamic models and by creating appropriate laboratory installations of a high power level. The measuring stand of the described structure allows to check the matching characteristics of all waveguide elements of the feeder chain, adjustment of waveguide tees, and the development and tuning of the energy input units to the microwave chamber of the experimental setup. In the laboratory installation it is proposed to use the industrial generator KIE-5, operating at a frequency of 2.45 GHz with a maximum output power of 5 kW and a waveguide ferrite circulator. The maximum power of such an installation differs only 10 times from the power of the experimental setup. This makes it possible to reliably estimate the electrical strength and heat release of the experimental unit assemblies from the results of laboratory studies.
Keywords: "izmeritel'nyy stend, sverkhvysokochastotnaya ustanovka, kirpich, sushka, obzhig, moshchnost', struktura, elektrodinamicheskoye modelirovaniye, eksperimental'naya ustanovka measuring stand, super-high-frequency installation, brick, drying, firing, power,
In the article the scheme of the measuring stand of the device model for determining the part of the energy distributed from the generator, the scheme of the measuring stand of the model for measuring the standing water coefficient (VSWR) and the measurement of the transient resistance are presented. The best results are obtained by a partition consisting of two metal plates overlapping the path both above and below the clay layer. So, with a clay humidity of 4%, the total attenuation was 14.4 dB (-6.1 dB without a partition), and at a humidity of 16% -35 dB (-18.4 dB without a partition). There is an increase in attenuation of approximately two times compared to the case without a partition for both dry and wet clay, but the amount of attenuation is insufficient. To increase the attenuation in model 2, two consecutive resonators were created. But the attenuation in this case increased insignificantly in comparison with one resonator. It is obvious that two resonators are upset because of mutual influence on each other. Therefore, it is proposed in a real installation between these two resonators to place a section of a waveguide of nonresonant length with an absorber that will eliminate the coupling between the resonators.
Keywords: measuring stand, super-high-frequency installation, brick, drying, firing, power, structure, electrodynamic modeling, experimental setup
The paper considers the method of experimental evaluation of the signal / noise ratio in relation to space communication systems. The basis of the high-precision evaluation method laid experimental signal / noise ratio is implemented by measuring the average number of the envelope of the additive mixture signal emissions and narrowband normal random process.
Keywords: Space communication system, command-and-measurement system, signal / noise ratio, the number of emissions, the envelope of the additive mixture, rms noise level restrictions, the sub-carrier frequency
This article describes electronic design software tools OrCAD implementation for the quadrature MSK-signals (minimum shift keying) modulator creation. Emulation results are presented: digital and analog signals, the output spectrum. The model is designed to generate MSK-signal and study their changes in various RF paths, using all possible analog-digital circuit simulation of OrCAD. The presented model is parametrized. The determinative model parameters are MSK-signal central frequency and pulse duration of modulation sequence. The input sequence - unipolar digital signal is read from an external text file. Realization of a parametric model of the MSK-signal modulator in OrCAD allows the researcher to quickly and easily change the parameters of the signal and to carry out research directly into the package without resorting to third-party software tools, thereby reducing the complexity and development time. The model can also be used in the study subjects issues concerning digital data transmission.
Keywords: circuit simulation, OrCAD, minimum-shift keying, quadrature modulator, parametric model
This article describes the model of the pseudorandom sequences (PRS) generator developed in OrCAD program suite.The described model is applicable for radio systems modules circuits simulation that are using in the operation a PRS. The PRS generator implementation in OrCAD make possible to change PRS parametres immediately in the program, without using other software. A model specificity is that it is parametrised. Parametrization facilitates model control and that is reduce to a minimum necessary manipulations for changing of PRS type. The model is constructed on the basis of circuitry implementation of the linear feedback shift register (LFSR). For adjustment of model it is enough to instal code words setting starting state a LFSR, parametres of a signal of a clock source and to specify register tap output. As an example, used a 16-bit LFSR to create maximum length PRS, tap sequence {0, 5, 9, 13}. Emulation results are presented.
Keywords: pseudorandom sequence, PRS generator, LFSR, OrCAD, circuit simulation