SU1506517A1 - Device for automatic stabilization of gain - Google Patents

Abstract

The invention relates to radio control systems for auto-regulation and can be used in radio transmitting equipment of the high-frequency and microwave ranges. The purpose of the invention is to reduce the distortion of the complex transmission coefficient in the range of frequencies and amplitudes. The device contains a controlled attenuator 1, a controlled phase shifter 2, an amplifier 3, an attenuator 4, a comparison element 5, a detector 6. A Schmidt trigger 7, a delay element 8, r-r 9 orthogonal amplitude-modulated signals are introduced into the device, two elements 10 and 11 of the sample storage. 3 il.

Description

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The invention relates to radio control systems for auto-regulation and can be used in radio transmitting equipment of high-frequency and microwave ranges.

The purpose of the invention is to reduce the distortion of the complex transmission coefficient in the range of frequencies and amplitudes -.

Fig. 1 shows the structural electrical circuit of the device proposed; FIGS. 2 and 3 are graphs illustrating the operation of the device,

The device for automatic gain stabilization contains a controlled attenuator 1, a controlled phase shifter 2, an amplifier 3, an attenuator 4, a comparison element 5, a detector 6, a Schmitt trigger 7, a delay element 8, a generator 9 of orthogonal amplitude modulated signals, the first and the second elements 10 and 11 of the sample storage.

The device works as follows.

In the stabilization mode, the path gain from the input to the output is equal to the attenuation coefficient of the attenuator 4, the error signals at the output of the comparison element 5, and therefore the output of the detector 6 are zero, the Schmitt trigger 7 is in the off state, the sampling elements - storage 10 and 11 in storage mode, generator 9 is turned off.

Element 5 Comparison responds to amplitude-phase imbalance of input signals. At a certain amplitude-phase imbalance, the error voltage at the output of the detector 6 reaches the threshold of the Schmitt trigger 7, it triggers the generator 9, and the elements of the sample-storage switch to the sampling mode. The control voltages of and to Ic) generated by the generator, shifted relative to each other by 90 °, are fed to the control circuits of the controlled attenuator 1 and the phase shifter 2, respectively. When the generator 9 is turned on, it begins to produce increasing control oscillating voltages with a period T, and and TsC) shifted relative to each other by 90 (Fig. 2 Over the full period T of the voltage U and Uy, the extremes pass twice, i familiar

Where

four

The orthogonality of stresses UK

and U (. allows us to consider the state of the system as some function F (and, and) on the phase plane with coordinates U ,, U. Let us set the state function as F and + U. The parametric formulas of the orthogonal components have view

it (s) P (t) cosQt; U / t) Q (t) sinS2t;

P (t) Pjl-exp (-t / € ,,) 1; Q (t) Q l-exp (-t / ,,)

radio pulse envelopes during their rise, 27/1, -,, - constant rise time, Рд and Q о - maximum values of signal amplitudes and and ЦЦ).

These waves form a system of equations for an elliptical unrolling helix on the phase plane. Similarly, a system of a collapsing elliptical helix corresponding to a decay of a radio pulse can be constructed. In FIG. Figure 3 shows the trajectory 12 of the movement of point A (U, and) along an unwinding spiral. The Hell point on the phase plane corresponds to the ideal amplitude-phase balance. The control accuracy is determined by the region of permissible deviations of point A from point Ad, which, in turn, depends on the thresholds for triggering the Schmitt trigger 7. The boundaries of these regions are shown as ellipses 13 and 14, the ratio of semi-axes of which, as is easily shown, is P / 0

When spiral 12 of the ellipse 13 crosses the voltage at the output of the detector 6, it becomes below the Schmitt trigger 7 closing threshold and it turns off. Due to the inertia of the regulation process, the moment of establishing the optimal state of the system is somewhat delayed and point A, corresponding to this moment, is inside the area bounded by the ellipse 13. I

When the Schmitt trigger 7 is triggered, the generator 9 is turned off, and the elements 10 and 11 of the sample-storage switch to storage mode. The path 12 segment corresponds to the slow discharge of capacitors in the element51.

Tax sampling-storage. At point A, for example, errors at the output of detector 6 exceed the switch-on threshold of Schmitt trigger 7, it turns on, generator 9 starts, sample-storage elements switch to sample mode, at which they follow the voltage at the generator outputs, which are equal to zero at the initial time of the trap (segment of trajectory 12). From this moment on, the cycle of searching for the optimal state is repeated.

Using the delay element 8, you can adjust the phase of the output signal.

Claims (1)

The possibility of automatic stabilization of the complex gain can be used when constructing multichannel systems based on the proposed device that require identical transmission characteristics of channels, for example, in phased antenna arrays, in transmitters with the addition of the power of several channels, in measurement technology. Invention Formula The device of automatic stabilization of the gain, contains 5065176 a series-connected controlled attenuator, a controlled phase shifter, an amplifier and an attenuator, as well as a comparison element and. A detector, characterized in that, in order to reduce the distortion of the complex transmission coefficient in the frequency range and amplitude This unit introduced a delay element connected between the input of the controlled attenuator and one of the inputs of the comparison element, the other input of which is connected to the output of the attenuator, the generator of orthogonal amplitude-modulated signals, the first and second sample-hold elements included between the orthogonal outputs of the generator of orthogonal amplitude-modulated signals and the control inputs of the controlled attenuator and the controlled phase shifter, respectively, and the Schmitt trigger, with the output of the element comparing is connected to the Schmitt trigger input through the detector, and the Schmitt trigger output is connected to the control inputs of the sample-storage elements and the orthogonal generator amplitude modulated signals. Phi2.2 12 X x I t ". 5l V - X .4, .i i - - ( FIG.