No abstract

HIGH-FREQUENCY AND MICROWAVE POWER AND VOLTAGE CALIBRATORSA. V. Myl'nikov, T. I. Petrova, and V. G. Chuiko UDC 53.083.8The construction of a high-frequency and microwave power and voltage calibrator based on a coaxial divider with a thermistor (thermoelectric) transducer is considered, and its characteristics are investigated. It is shown that the transfer factor is close to unity, while the modulus of the equivalent reflection coefficient does not exceed 0.05 in the 0-8 GHz frequency band and is not greater than 0.08 in the 8-18 GHz frequency band.When designing aggregated high-frequency and microwave power and voltage standards in coaxial channels, one needs to include a transmission multifunctional measuring instrument in them. Power and voltage calibrators, i.e., generators with a known value of the parameter characterizing the signal strength, are the most widely used form of working standard when measuring high-frequency and microwave power and voltage. At frequencies below 100 MHz, voltage calibrators are largely used. At frequencies greater than 1 GHz there are only power calibrators. In the 150 MHz-I GHz frequency band there are both power calibrators (for example the VPO-1 or Ya2M-23), and voltage calibrators (for example, the VI-15). Note that power calibrators for the 10-150 MHz frequency band are also required, since microwave wattmeters of group M3 have a low limiting frequency of about 10 MHz (for example, the M3-90) or a constant current (for example the M3-93). Voltage calibrators for frequencies higher than 1 GHz are also required, because such instruments as stroboscopic oscilloscopes are graduated in voltage for the 0-18 GHz frequency band. The power and the voltage in the output plane of the calibrator clearly depend on its output impedance and the load impedance. But in many important practical cases the errors of the measuring instruments (for example, spectrum analyzers, radio-noise measuring instruments and voltmeters) are normalized for standardized and equal input and output impedance, for example, 50 ohm or 75 ohm. One then takes as the actual value the power or the voltage delivered by the calibrator to a matched load, so that the instrument serves as a power and voltage calibrator.Coaxial microwave power calibrators used in this country have been traditionally developed using directional couplers. At present the calibrators with coaxial couplers (Ya2M-23, Ya2M-24, VPO-1-VPO-4) and waveguide couplers having a waveguide-coaxial transformer (M1-6B, M1-8B, and M1-9B) are used in metrological laboratories [1]. The main advantage of power calibrators based on directional couplers is the low effective reflection coefficient I" e of the calibrator output, due to the high directivity of the coupler. However, it is not possible to obtain a high directivity over a wide frequency band, and at low frequencies directional couplers are very large. In foreign coaxial power calibrators a two-resistor power divider is connected in the system instead of a directional coupler [2]. This divider, unlike a...

No abstract

A. V. Koudel'nyi and V. G. Chuiko UDC 53.083.8The results are given of developments and investigations of an automated apparatus for calibrating attenuators in the frequency range 10 MHz to 18 GHz for use as working attenuation standards. It is shown that automated apparatus for calibrating microwave wattmeters is suitable for calibrating coaxial fixed and stepped attenuators with an error of lower than +0.02 dB per 10 dB.Calibrated attenuators are convenient as standard devices for measuring amplitude ratios and are employed in the frequency range from tens of kilohertz to hundreds of gigahertz. They are introduced into standards for power, voltage, and other quantities in order to extend their measuring range. It is preferable to use amplitude-ratio standards rather than ratio meters because the cost of a device for establishing (forming) a known signal amplitude ratio by means of a calibrated attenuator is far lower than that of a ratio meter of the same accuracy, and the reliability is higher. Coaxial programmed stepped and fixed attenuators such as the Hewlett Packard series 8490, 8494, and similar have been extensively used in practice. A distinctive feature of fixed and stepped coaxial attenuators is the presence of steps from the series 3, 6, 10, 20, and 30 dB for Russian devices or I0, 20, 40, 50, and 60 dB for foreign devices. Programmed attenuators have steps of 0.1, 1, and 10 dB (for example, type TR Hungarian attenuators or type BM Czech attenuators) or steps arranged as 1-2-4-4 or 10-20-40-40 as for the Hewlett Packard attenuators. Such attenuators are extremely convenient as working standards (standard devices) and comparison standards for calibrating attenuation, and for the comparison of different types of measuring receivers, radio interference meters, group $4 spectrum analyzers, group D 1 heterodyne attenuation meters, group F4 devices for measuring group time delay, group R2 panoramic VSWR meters, group Kh5 noise figure meters, group $2 and $3 devices for measuring amplitude and frequency modulation depths, group $7 and $9 rf oscilloscopes, group V3 rf voltmeters, etc. As a rule working standards of attenuation for coaxial lines, with an error of lower than 0.03 dB per 10 dB are suitable. However the errors of fixed and stepped attenuators given in the catalogs of firms fail to satisfy some of the requirements, although it is known that the instability of attenuators is normally considerably lower than the stated errors. Consequently they can be certified as working standards after careful measurements, as was mentioned in [1].By definition, attenuation is the ratio of the powers at the input and output of an attenuator for the traveling wave regime at its input and output. For attenuators with values below 40 dB it is possible to measure their attenuation by the power ratio method, by definition, using power meters. The schematic diagram shown in Fig. 1 is well known. According to data in [ 1, 2] the minimum error of the power ratio method, resulting from the random errors of the thermistor ...

In this article of the Doctor of Philosophy, professor of Taras Shevchenko Kyiv National University, Chuiko Vadim Leonidovich and Atamanchuk-Angel Valerii Ivanovich is applied the principle of «first philosophy» as the foundation of the a priori prerequisites of possible cognition, which define an existence in general rather than its individual parts. This application of metaphysics made it possible to introduce methods of «universal algebra» for the implementation of humanitarian research using algebraic description with the help of three notion: plural, operations, relation. This methodological novation makes it possible to create demonstrative models of social systems, not their constructions, because constructionsare traditionally makeby using binary description that use only two notions, categories. Question: How to fill the notion of «public agreement» with the actual content? How to make all generations participate in the adoption of a social contract? How to create a new one, without destroying it entirely, maintaining stability? How to ensure a high degree of mutation — rebuilding, rebuilding and construction? Introduced in the algebraic sense, the notion of «trust» as a definition of what is necessary for the existence of a society of being as such, forms an algebra that models social relations by the operation of trust, not violence. Based on the above, we can talk about creating a mathematical politics. Matpoliticsdeal with ideal political objects. Matpolitics is the activity of a summation of algebras. These algebras differ from each other by the choice of operations. Plurals that consist of different algebras can be the carrier of the algebra. In this case, we are talking about the algebra of trust / credo, whose signature consists of the following operations: sovereignty, trust / credit, understanding of need for the Other, agreement and recursive procedures. The result of the implementation of these methodological guidelines are the answers to the following questions: How to make the concept of «social agreement» really meaningful? How can all generations (and the unborn, too) be involved in the social agreement? How to create a new one, without destroying the foundations of the existing one, to realize the idea of conservative development: restructuring and building a new one? Based on the provisions of the algebra of trust, society appears as a plurality of sovereigns — C, possessing the full range of rights to identify trust / distrust — Di, creating agreements — Yn, and for their completeness they have and understand the need for the other — Ik. The model presented is a system of treaties that are not an abstract concept of the state, but an agreement with specific elected people who have gained the trust of those to whom they temporarily render their services. Agreements are urgent, limited by time frame, with obligatory full responsibility of the parties.