RU2565522C2 - Radio-pulse frequency multiplier - Google Patents

Abstract

FIELD: physics, radio.

SUBSTANCE: invention relates to radio engineering, particularly to frequency synthesizers. The radio-pulse frequency multiplier includes two switches and a self-oscillator, which enable to generate a radio pulse with a constant initial phase, wherein the self-oscillator is a two-stage resonance amplifier with a positive feedback with two resonance circuits and two switches, connected to said resonance circuits, one of the switches being an input switch, and the output signal is obtained from one of the oscillatory circuits.

EFFECT: high frequency multiplication factor.

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Description

Radio pulse frequency multiplier - refers to radio engineering, namely to frequency synthesizers.

Frequency multipliers are known in which the input signal is distorted to obtain the required harmonics. The disadvantages of these multipliers are the low multiplication factors of the frequency and transmission of the Converter.

The closest in technical essence to the proposed multiplier is the well-known radio-pulse multiplier (Grigulevich V.I., Immoreev I.Ya. “Radio-pulse frequency conversion”, M., Soviet radio, 1966).

In such multipliers, pulse sequences have a high-frequency filling (radio pulses). The maximum harmonics required are located near the fill frequency. The energy of the process is grouped around this frequency. The initial phase of high-frequency filling from pulse to pulse should be constant. Which determines the basic requirements for the elements of the radio pulse multiplier during the formation of radio pulses.

When studying the process of establishing the stationary amplitude of one of the elements of a radio pulse multiplier (self-oscillator) using the shortened equation, the formulas were obtained (Baskakov SI “Radio-technical circuits and signals”, M., Higher School, 2003, pp. 377-378)

as t → ∞, the oscillation amplitude tends to a constant stationary level.

Where:

U (t) is the amplitude of the oscillations as a function of time;

U ₀ - the amplitude of the oscillations of the initial level;

U (st) is the amplitude of the oscillations of the stationary level;

α, β are the coefficients of the shortened equation, which, in turn, are determined by the formulas:

Where:

a ₁ , and ₃ are the coefficients of the current-voltage characteristics of a nonlinear element having the form of a power series:

M, L, C, R - characteristics of the oscillatory circuit.

We note the following, if Uo = 0, then, in accordance with the formula, the oscillation amplitude U (t) is equal to zero for any t> 0. For α> 0, the mode of small oscillations is unstable, and for any arbitrarily small Uo, self-excitation of the self-oscillator will always take place. We note that Uo arises from thermal noise under shock excitations.

Note that with an increase in the quality factor of the oscillatory system (as R → 0), the parameter α increases and the stationary amplitude is established the faster, the higher the quality factor of the oscillatory circuit.

The technical task of the proposed frequency multiplier is to further increase the multiplication coefficient of the radio pulse frequency multiplier.

The technical result is achieved by increasing shock waves during the formation of radio pulses and by increasing the quality factor with the introduction of positive feedback.

The implementation of the proposed multiplier consists in the use in the oscillator of a two-stage resonant amplifier with positive feedback and two keys.

The proposed multiplier not only allows you to increase the multiplier of the frequency multiplier, but when using strip technology to create small-sized devices.

As a result of the experiment, a frequency multiplier was obtained based on the strip technique with the following parameters: input frequency 1 MHz, output frequency 115 MHz, i.e. a multiplication factor of n = 115 was obtained.

The multiplier contains two keys made on transistors T1 and T4, as well as an oscillator made on transistors T2 and T3, which, together with the circuits L1C1 and L2C2, are connected according to the scheme of a two-stage resonant amplifier with positive feedback. The collectors of the key transistors T1 and T4 are connected respectively to the oscillatory circuits of the oscillator L1C1 and L2C2.

The scheme of the proposed radio pulse multiplier is shown in the drawing, which shows the relationships and elements that display the essence of the proposed multiplier.

Claims (1)

A radio frequency multiplier comprising two keys and a self-oscillator, providing a radio pulse with a constant initial phase, characterized in that it contains a self-oscillator, which is a two-stage resonant amplifier with positive feedback with two resonant circuits and two keys connected to these resonant circuits, one of the keys is input, the output signal is taken from one of the oscillatory circuits.