SU862350A1 - Self-excited oscillator - Google Patents

Description

(54) AUTOGENERATOR

one

The invention relates to radio engineering and can be used in devices for generating electromagnetic oscillations in radiolocation, automation and space radio communication.

The known oscillator contains a transistor, the collector circuit of which includes the contours of the main and second harmonics, made in the form of an open segment of the strip transmission line, and matching circuit 1.

However, such an oscillator is low power and low frequency stability of the second harmonic.

The purpose of the invention is to increase the power and frequency stability of the second harmonic.

For this, an oscillator containing a transistor, the collector circuit of which includes the contours of the main and second harmonics, made in the form of an open segment of the strip transmission line, and the matching circuit additionally introduced an idle circuit tuned to the third harmonic and made in the type of the second open segment of the strip transmission line . In this case, the idle circuit is connected to the contours of the main and second harmonics through the additionally introduced segment of the strip transmission line, whose length is equal to the third harmonic wavelength, and the matching circuit is connected parallel to the idle 5 circuit.

The drawing shows a structural electrical circuit of the proposed auto generator.

The oscillator contains a transistor 1, the emitter of which includes a phasing 10 slot 2 shorter than 1/4 of the main harmonic wavelength, and a collector circuit 3 of the main and second harmonics in the collector circuit, made in the form of an open segment of the strip transmission line, idle circuit 4, tuned to the third harmonica and performed

15 in the form of a second open segment of a strip transmission line, matching circuit 5 and segment 6 of a strip transmission line whose length is equal to the wavelength of the third harmonic.

20 Auto generator works as follows.

After turning on the emitter and collector power of transistor 1, thanks to

the phasing loop 2 included in the emitter and the contours 3 of the main and second harmonics in the circuit are set to stationary oscillations of the main and second harmonics. The idle circuit 4, which is connected at a distance of the third harmonic wavelength from the contour of the extracted harmonic and tuned to the third harmonic (the fourth wavelength of the third harmonic), increases the fixing ability of the collector circuit of the transistor and, therefore, the frequency stability of the generated oscillations of the extracted (second) harmonic which are fed through the matching circuit 5 to the output of the device.

Thus, switching on the idle circuit 4 with a length equal to a quarter of the third harmonic wavelength, at a distance of the third harmonic wavelength from the contour of the extracted harmonic (the second) is equivalent to an increase in the slope of the phase-frequency characteristic (phase response) of this circuit.

Really

", Tf -

J f

whereC 3 10, from where the further increase between the point of connection of the circuit and the generating system, we increase the slope of the phase response (-) of this circuit, and hence its fixing ability. An increase in the fixing ability of the circuit connected to the generating system increases the frequency stability of the oscillations. The distance (length 1) at which the idle circuit 4 is connected must be chosen in a compromise: from the condition of the maximum response of the generating system to the idle circuit (or the minimum damping of oscillations in the path of the generator), the idle system – idle circuit — the generating system (or the maximum slope of the frequency response).

The optimal length, at which the stabilizing idle circuit 4 is turned on, for the second harmonic oscillator is equal to the tuning wavelength of the connected idle circuit. In this case, the fixing ability of the connected idle circuit increases by a factor of 1, and aX is the third harmonic wavelength. This makes it possible to apply a low-Q resonator according to the third harmonic, made, for example, in the microstrip version.

Phasing loop 2 allows to reduce the phase shift OJLj between the microwave current and the voltage of the collector circuit of the transistor, and thus increase the efficiency and power of the generated oscillations. A decrease in the phase shift (p3t is equivalent to adjusting the fundamental frequency contour, which leads to an increase in the slope of its phase response.

The increase in the slope of the frequency response of the idle circuit by assigning the point of its connection from the contour of the extracted harmonic to a distance equal to the wavelength of the third harmonic on the one hand, and increasing

the steepness of the frequency response of the fundamental frequency circuit due to the inclusion of the phasing loop in the emitter circuit on the other hand improves the fixing ability of the collector circuit of the transistor as a whole and, therefore, the stability and power of the generated oscillations.

In addition to increasing the fixing ability of the collector circuit of the transistor, a form of microwave voltage is stabilized

j and the collector of the transistor does not change when the length of the line changes (for example, under the influence of the ambient temperature), which connects the idle circuit and the contours of the extracted and main harmonics, since the rto of this line moves both the reflected third harmonic wave and the reflected The main voltage wave voltage circuits.

The optimal form of microwave voltage is

- the collector of the transistor (from the point of view of maximum frequency stability and power generation) corresponds to the optimal phase ratio between the fundamental and third harmonics, the voltage waves of which circulate along the same

0 ways. The optimum phase ratio between the main and third harmonics in the process of resizing the line, combining the contours of the extracted, main harmonics, idle contour and matching circuit, changes in such a way that the voltage

 the collector remains constant.

Thus, the stabilization of the frequency and the increase in the power of second-harmonic generation are the result of the introduction of a new element of the idle circuit 4, which is included at a distance equal to the wavelength of the third harmonic, from the contour of the selected and main harmonics as a whole.

Claims (1)

Invention Formula An oscillator containing a transistor whose collector circuit includes the contours of the main and second harmonics, made in the form of a first open segment a stripline transmission line, and a matching circuit, characterized in that, in order to increase the power and frequency stability of the second harmonic, an idle circuit added to the third harmonic and made as a second open section of the stripline transmission line is additionally introduced, while the idle circuit is connected whose to the contours of the main and second harmonics through the additionally introduced segment of the strip transmission line, whose length is equal to the wavelength of the third harmonic, and the matching circuit is connected parallel to the idle end tour Sources of information taken into account during the examination 1. USSR Author's Certificate No. 371659, cl. NOSV7 / 06, 1974 (prototype) ff 4 u ////////