SU983587A1 - Method of measuring slow-wave structure dispersion characteristics - Google Patents

Description

The invention relates to microwave electronics and can be used in the development of an EVE of microwave and passive microwave nodes containing decelerating systems (ES).

There is a known method for measuring the dispersion characteristic of an ES using a perturbing body method, which is carried out as follows.

A squirrel-cage on both sides is tuned to resonance and, through it, to a thin filament. a small perturbing body (passive probe). Register the departure of the resonant frequency, you can determine the wavelength in system 1.

However, a methodical measurement error arises due to the introduction of a dielectric into the ES flying channel (a perturbing body). It should be noted that measurement errors associated with the drawbacks of the method, -., increase as the wavelength of the measured range decreases, and therefore the dispersion characteristics of the shortwave ES are measured on the enlarged layouts. The disadvantage of such a simulation is that it does not simulate the structural and technological features of manufacturing a real CS node (surface roughness, influence of tolerances, quality of RF contacts, formation of solder fillets at the joints of soldered surfaces, etc.).

The closest technical solution to the invention is clearly the measurement of dispersion characteristics of slow-wave systems, including the measurement of the resonant frequencies of short-circuited layouts with a different number of cells and the subsequent identification of the types of oscillations corresponding to these frequencies r2J.

The disadvantage of this method is that to determine a one-to-one correspondence between Vn and

J-. f it is necessary that all (N + 1) types of oscillations are excited in resonant ah mockups of the CS.

However, it is known that, depending on the configuration of the CS and the type of oscillations, resonances at frequencies corresponding to certain types of oscillations (for example, near the bandwidth limits) cannot be excited.

Claims (2)

The aim of the invention is to reduce the labor intensity and improve the accuracy of determining the dispersion characteristics with a known type of dispersion when exciting certain types of vibrations. The goal is achieved according to the method of measuring the dispersion characteristics of slowing systems, including the measurement of resonant frequencies, short circuits of mock-ups with a different number of cells and the subsequent identification of the types of oscillations corresponding to these frequencies, are measured on two models differing in the number of cells in M times / where M is a prime number, the resonant frequencies of both models are measured, matching frequencies are selected, and the dispersion characteristic is judged by the number of factors. Moreover, in the absence of resonant frequencies that follow the resonant frequency, which coincides in both models, the latter is identified with the bandwidth limit, and if the resonant frequencies follow the resonant frequency, which coincides in both models, the latter identifies with oscillation modes that shift by cell tf rr-rr M and .. 7, depending on the type of var M The essence of the proposed method is 6 as follows. There are two empty cell layouts; N and N, respectively. Moreover, according to the claims of the invention N. M p g and Nqf M p, where M is a prime number, and the numbers n, and n, j are mutually simple (i.e., have no common factors). In model No. 1, resonances are possible at frequencies corresponding to phase shifts per cell where k is 0.1.,. Mp Model V, where, l .. .M It is not difficult to see that common to both models will be resonant modes of oscillation, with phase shifts PJ-Wj -ai. .gi (i1 ..- KMltj Ir.f -4.),. In the case when O or amp is absent, the bandwidth limit is determined by the resonant frequency following the resonant frequency that is the same for both layouts. When there were no modes of oscillations with O and 1T, the remaining general views are sufficient to identify the resonant frequencies. In this case, since these variances are known, identification is carried out unambiguously. For example, with normal dispersion, large of coincident frequencies correspond to the type of oscillations} 4 P anomalous dispersion (9 jijic). The number M is chosen in advance, depending on which type of oscillation will be carried out. For example, if M 2 (both models with an even number of cells), then the identification is carried out in a single general form. For any other M / 2 identifiers, Katsi is carried out in two general types (i7Gi. Let us give a specific example of the implementation of the proposed method. Suppose that the types of oscillations that are under study in ZP are 0 with It and. identification of which will be carried out with, for example, V and f-J In this case, in accordance with the proposed method, we define the possible numbers of cells of the two test models N Mn and .- According to the proposed method, n must be mutually simple, for example, or, etc. In We take the second case, i.e., N b, N /. 9. It is easy to see that the types of oscillations with and common to both layouts 1 2 2 are given with tf -7G and (d, which can be identified by the coincidence. of the resonant frequencies of both make-ups. Note that the absence of one or several types of oscillations in resonant dummies can occur in the study of an AP with selective absorbers. Theoretical analysis of such ES is currently not available, so the proposed method is It is effective in determining dispersion characteristics. tic of such systems. It should also be noted about the meaning of the term coincidence of resonant frequencies. Such a coincidence can take place only within the experimental error, which in turn is the sum of the error of the method of measuring the resonant frequencies (usually 10) and the difference of the resonant frequencies corresponding to the same type of oscillation in different layouts due to inaccuracies in the manufacture of mockups. The current value, taking into account the current accuracy of manufacturing and assembling the layouts, is estimated as 10. Therefore, it is necessary to consider the resonant frequencies to coincide, provided that their difference is less than the error associated with the manufacture of the layout. The advantage of the proposed method in comparison with the known method is the possibility of determining the influence of ES manufacturing errors on the dispersion characteristic. Simultaneously with the measurement of the dispersion characteristic itself. The results shown / show that the proposed method is not more difficult in complexity than the known one, but exceeds its efficiency in cases where one or several kinds of vibrations are not excited. The method is tested when measuring the dispersion characteristics of an ES type of a chain connected by a resonator in the shortwave part of the centimeter range, in resonant dummies of which the mode of oscillation was not excited, and resonantly often the type of f o. outside the working range of the measuring device. The use of this method makes it possible to avoid the production of enlarged layouts and the use of laborious probe methods. Claims of the Invention. A method for measuring the dispersion characteristics of slowing systems, including the measurement of resonant frequencies of short-circuited models with a different number of cells and the subsequent identification of the types of oscillations corresponding to these frequencies, in order to lower the TVV and improve the accuracy of measurement dispersion characteristics with a known type of Persia when individual, types of vibrations are excited., measurements are carried out on two models, differing in the number of cells in M times, where M is a prime number, measured , the resonant frequencies of both layouts, choose the same frequency, the number of which is judged on the dispersion characteristic. 2, Method POP1, characterized in that in the absence of resonant frequencies following the resonant frequency coinciding in both models, the latter is identified with a bandwidth boundary. 3. Method according to Claim 1, characterized in that, in the presence of resonant frequencies, following the resonant frequency coinciding in both layouts, the latter is identified with modes of oscillations having i and y ± 1G shift by cell ff jjfc and JJ L dependencies on-type dispersion. Sources of information taken into account during the examination 1.Budnik V.V., Khakhileva G.A. Methods for measuring the parameters of high-frequency EVP systems with extended BM interaction. Collection of electronic technology, vyp.Z (186), M., Central Research Institute of Electronics, 1974, p. 16-18. 2. Waldner O.A. and others. Technique sverhvneshennyh frequencies. M., Atomizdat 974, p. 134 (prototype).