RU2777749C1 - Method for generating and frequency modulation of high-frequency signals and a device for its implementation - Google Patents

Abstract

FIELD: radio communication.

SUBSTANCE: inventions relate to the fields of radio communications, radar, radio navigation and electronic warfare and can be used to create generation and frequency modulation devices with an increased linear section of the frequency modulation characteristic at arbitrary frequency characteristics of the load. The method for generating and frequency modulation of high-frequency signals is based on the conversion of the energy of a DC voltage source into the energy of a high-frequency signal, the interaction of a high-frequency signal with a direct transmission circuit, a three-pole nonlinear element, a reactive four-pole, a load and an external feedback circuit, the fulfillment of excitation conditions in the form of a balance of amplitudes and phase balance, respectively, determining the amplitude and frequency of the generated high-frequency signals, the conditions for matching the direct transmission circuit with the load and the conditions for matching the load with the control electrode of a three-pole nonlinear element, changing the frequency of the generated oscillations according to the law of changing the amplitude of the low-frequency control signal by changing the phase balance accordingly, while the load is performed in the form of a first two-pole with a complex resistance, an arbitrary four-pole connected in series to the three-pole nonlinear element, the three-pole nonlinear element and a feedback circuit as a single node are cascaded between the introduced second two-pole with a complex resistance, simulating the resistance of the generator signal source in the amplification mode, and the input of a reactive four-pole, to the output of which a load is connected, the excitation conditions in the form of a balance of amplitudes and phase balance and the matching conditions are fulfilled by selecting the dependences of the parameters of the reactive quadrupole on the frequency from the condition of ensuring a stationary generation mode in the form of zero denominator of the transmission coefficient in the amplification mode sequentially at all frequencies of a given frequency band with a corresponding change in the amplitude of the low-frequency signal.

EFFECT: generation and frequency modulation of a high-frequency signal with an increased linear section of the frequency modulation characteristic when using a single nonlinear element and arbitrary complex load resistances, which makes it possible to create effective generation and frequency modulation devices, as well as to increase the range of generated oscillations when using a reactive basis with concentrated parameters and any given frequency characteristics of the load, for example, antennas.

2 cl, 4 dwg

Description

The inventions relate to the fields of radio communications, radar, radio navigation and electronic warfare and can be used to create devices for generating and frequency modulation with an increased linear section of the frequency modulation characteristic for arbitrary frequency characteristics of the load.

A known method for generating and frequency modulating a high-frequency signal is based on converting the energy of a DC voltage source into the energy of a high-frequency signal, organizing internal feedback in the first non-linear element by using a bipolar non-linear element with negative differential resistance as it, fulfilling the excitation conditions in the form of a balance of amplitudes and phase balance, which determine the amplitude and frequency of the generated high-frequency signal, respectively, and the conditions for matching the first nonlinear element with the load, changing the frequency of the generated high-frequency signal by changing the phase balance by changing the parameter of the second nonlinear element included in the selective load, according to the law of changing the amplitude of the low-frequency control ( primary, informational) signal [Gonorovsky I.S. Radio circuits and signals - M: Bustard, 2006, p. 414-417, 434-437].

A device for generating and frequency modulating a high-frequency signal is known, consisting of a constant voltage source that sets the operating point in the middle of the falling section of the current-voltage characteristic of a two-pole non-linear element with negative differential resistance, a reactive quadripole, a load in the form of a parallel oscillatory circuit with a varicap connected to a control signal source , while the parameters of the circuit, a bipolar nonlinear element and a varicap are selected from the condition of providing the specified amplitude and frequency range of the generated high-frequency signal according to the law of the change in the amplitude of the low-frequency control (primary, information) signal [Gonorovsky I.S. Radio circuits and signals - M: Bustard, 2006, p. 414-417, 434-437].

The principle of operation of this device is as follows. When the source of direct voltage (current) is turned on, due to the abrupt change in amplitude, oscillations occur in the entire circuit, the spectrum of which occupies the entire radio frequency range. The amplitudes of these oscillations decay rapidly. However, due to the presence of internal feedback in a two-pole non-linear element, a negative differential resistance arises in the section with a falling current-voltage characteristic, which, due to matching with the help of a reactive quadripole, compensates for losses in the circuit. Due to this, an oscillation with a frequency equal to the resonant frequency of the oscillatory circuit is amplified until the amplitude of this oscillation increases to a level at which the amplitude goes beyond the falling section of the current-voltage characteristic. There is a stationary regime. In this mode, a change in the capacitance of the varicap under the action of a control signal leads to a change in the frequency of the generated signal according to the law of the change in the amplitude of the low-frequency signal.

The disadvantage of the method and device is the presence of two non-linear elements, one of which works as an amplifier and limiter, and the second is used to change the frequency of the generated high-frequency signal.

The closest in technical essence and the achieved result (prototype) is a method for generating and frequency modulating a high-frequency signal, based on converting the energy of a constant voltage source into the energy of a high-frequency signal, building a direct transmission circuit between the output electrode of a three-pole non-linear element and the load, organizing an external positive feedback between the load and the control electrode of the three-pole non-linear element, fulfillment of the excitation conditions in the form of amplitude balance and phase balance, which determine the amplitude and frequency of the generated high-frequency signal, respectively, and the conditions for matching the three-pole non-linear element with the load, changing the frequency of the generated high-frequency signal by changing the phase balance by changing parameter of a two-pole non-linear element included in the selective load, according to the law of the change in the amplitude of the low-frequency control (primary, information) signal cash [Gonorovsky I.S. Radio circuits and signals - M: Bustard, 2006, p. 434-437].

The closest in technical essence and the achieved result (prototype) is a device for generating and frequency modulation of a high-frequency signal, consisting of a constant voltage source that sets the operating point in the middle of the quasi-linear section of the pass current-voltage characteristic of the transistor, a direct transmission circuit in the form of the first four-pole to match the output electrode of the transistor and loads, loads in the form of a parallel oscillatory circuit, which includes a varicap connected to a control signal source, RC - external positive feedback circuits (in general, a second quadripole for matching the control electrode of the transistor and the load) between the load and the control electrode of the transistor, at the same time, the parameters of the circuit, the direct transmission circuit, the feedback circuit, the transistor and the varicap are selected from the condition of providing the specified amplitude and frequency change range of the generated high-frequency signal according to the law of change the amplitude of the low-frequency control (primary, information) signal [Gonorovsky I.S. Radio circuits and signals - M: Bustard, 2006, p. 434-437].

The principle of operation of this device is as follows. When the source of direct voltage (current) is turned on, due to the abrupt change in amplitude, oscillations occur in the entire circuit, the spectrum of which occupies the entire radio frequency range. The amplitudes of these oscillations decay rapidly. However, due to the presence of an external positive feedback circuit, an oscillation with a frequency equal to the resonant frequency of the oscillatory circuit enters the control electrode of the transistor, which, due to matching with the help of two quadripoles, begins to operate in amplification mode until the amplitude of this oscillation increases to a level at which saturation mode occurs (amplitude limitation). There is a stationary regime. In this mode, a change in the capacitance of the varicap under the action of a control signal leads to a change in the frequency of the generated signal according to the law of the change in the amplitude of the low-frequency signal.

The disadvantages of this method and device are the need to use two nonlinear elements (one for amplification and amplitude limitation, the second for changing the frequency) and a small linear section of the modulation characteristic due to the smallness of the linear section of the capacitance-voltage characteristic of the varicap. In addition, it is not indicated how it is necessary to choose the values of the parameters of both quadripoles, at which the excitation regime and the stationary regime begin. This question arises especially acutely when designing generation and frequency modulation devices in the HF and UHF bands, in which it is necessary to take into account the reactive components of the parameters of nonlinear elements. At present, the classical theory of radio circuits does not take this into account. In addition, frequency modulation can be provided at any load resistance, which leads to an expansion of the field of use of frequency modulators.

The technical result of the invention is the generation and frequency modulation of a high-frequency signal with an increased linear section of the frequency modulation characteristic using a single non-linear element and arbitrary complex load resistances, which allows you to create efficient generation and frequency modulation devices, as well as increase the range of generated oscillations when using a reactive basis with lumped parameters and any given frequency characteristics of the load, for example, an antenna. The possibility of using various options for switching on a three-pole nonlinear element with respect to a matching four-terminal network and various types of feedback expands the possibilities of the physical feasibility of this result.

1. This result is achieved by the fact that in the known method of generation and frequency modulation of high-frequency signals, based on the conversion of the energy of a DC voltage source into the energy of a high-frequency signal, the interaction of a high-frequency signal with a direct transmission circuit, a three-pole nonlinear element, a reactive quadripole, a load and an external reverse circuit connection, fulfillment of the excitation conditions in the form of amplitude balance and phase balance, which determine the amplitude and frequency of the generated high-frequency signals, respectively, the conditions for matching the direct transmission circuit with the load and the conditions for matching the load with the control electrode of a three-pole non-linear element, changing the frequency of the generated oscillations according to the law of changing the amplitude of the low-frequency control signal by a corresponding change in the phase balance, additionally, the load is performed in the form of the first two-terminal network with complex resistance, as an external feedback circuit, an arbitrary two-terminal network connected to a three-pole non-linear element in a series-parallel circuit, a three-pole nonlinear element and a feedback circuit as a single node are cascaded between the introduced second two-terminal network with a complex resistance, simulating the resistance of the generator signal source in the amplification mode, and the input of the reactive quadripole, to the output which the load is connected, the excitation conditions in the form of a balance of amplitudes and a balance of phases and the matching conditions are performed by choosing the dependences of the parameters of the reactive quadripole on frequency from the condition for ensuring the stationary generation mode in the form of equality to zero of the denominator of the transfer coefficient in the amplification mode sequentially at all frequencies of a given frequency band at the corresponding change in the amplitude of the low-frequency signal in accordance with the following mathematical expressions:

where

- оптимальные зависимости отношений соответствующих элементов классической матрицы передачи от частоты в заданной полосе частот;

- заданные зависимости отношений соответствующих элементов классической матрицы передачи от частоты в заданной полосе частот; а, b, с, d - элементы классической матрицы передачи;

- заданные зависимости действительной и мнимой составляющих сопротивления источника входного высокочастотного сигнала генератора в режиме усиления от частоты в заданной полосе частот;

- заданные зависимости действительной мнимой составляющей сопротивления нагрузки от частоты в заданной полосе частот;

- заданные суммы зависимостей действительных и мнимых составляющих элементов смешанной матрицы Н трехполюсного нелинейного элемента от частоты в заданной полосе частот при соответствующем изменении амплитуды низкочастотного управляющего сигнала и зависимостей соответствующих действительных и мнимых составляющих элементов смешанной матрицы H цепи внешней обратной связи

от частоты в заданной полосе частот.

- optimal dependences of the ratios of the corresponding elements of the classical transmission matrix on the frequency in a given frequency band;

- given dependences of the ratios of the corresponding elements of the classical transmission matrix on the frequency in a given frequency band; a, b, c, d - elements of the classical transfer matrix;

- given dependences of the real and imaginary components of the resistance of the source of the input high-frequency signal of the generator in the amplification mode on the frequency in a given frequency band;

- given dependences of the real imaginary component of the load resistance on the frequency in a given frequency band;

- given sums of dependencies of the real and imaginary constituent elements of the mixed matrix H of a three-pole nonlinear element on the frequency in a given frequency band with a corresponding change in the amplitude of the low-frequency control signal and the dependencies of the corresponding real and imaginary constituent elements of the mixed matrix H of the external feedback circuit

on the frequency in a given frequency band.

причем двухполюсники с сопротивлениями

сформированы в виде параллельно соединенных параллельного колебательного контура из элементов с параметрами

и последовательного колебательного контура из элементов с параметрами

, а значения параметров определены из условия согласования по критерию обеспечения стационарного режима генерации на четырех частотах и соответствующих четырех значениях амплитуды низкочастотного управляющего сигнала с помощью следующих математических выражений:2. This result is achieved by the fact that in the device for generating high-frequency signals, consisting of a constant voltage source and a low-frequency control signal, a direct transmission circuit of a three-pole non-linear element and a reactive four-terminal circuit, a load and an external feedback circuit, the load is additionally made in the form of the first two-terminal circuit with complex resistance, the external feedback circuit is made in the form of an arbitrary four-pole connected to a three-pole nonlinear element in a series-parallel circuit, a three-pole nonlinear element and a feedback circuit as a single node are cascaded between the introduced second two-terminal circuit with a complex resistance that simulates the resistance of the input high-frequency source generator signal in the amplification mode, and the input of the reactive quadripole, to the output of which the load is connected, the reactive quadripole is made in the form of an overlapped T-shaped connection of four reactive th two-terminal networks with resistances

moreover, two-terminals with resistances

formed in the form of parallel connected parallel oscillatory circuit of elements with parameters

and a serial oscillatory circuit of elements with parameters

, and the values of the parameters are determined from the condition of matching according to the criterion of ensuring the stationary mode of generation at four frequencies and the corresponding four values of the amplitude of the low-frequency control signal using the following mathematical expressions:

where

- номер частоты;

- заданные значения действительной составляющей сопротивления нагрузки на четырех частотах;

- заданные суммарные значения действительных и мнимых составляющих элементов смешанной матрицы Я трехполюсного нелинейного элемента на заданных четырех частотах и заданных четырех значениях амплитуды низкочастотного управляющего сигнала и соответствующих действительных и мнимых составляющих элементов смешанной матрицы Я цепи внешней обратной связи

на заданных четырех частотах; k = 2, 3 - индекс, характеризующий соответствующие номера реактивных двухполюсников с сопротивлениями

- заданные равные значения сопротивлений первого и четвертого двухполюсников перекрытой Т-образной схемы на заданных четырех частотах.r _nm ., x _0m - the given values of the real and imaginary components of the resistance of the source of the input high-frequency signal of the generator in the amplification mode at four frequencies

- frequency number;

- given values of the real component of the load resistance at four frequencies;

- the given total values of the real and imaginary constituent elements of the mixed matrix R of a three-pole nonlinear element at the given four frequencies and the given four values of the amplitude of the low-frequency control signal and the corresponding real and imaginary constituent elements of the mixed matrix R of the external feedback circuit

at the given four frequencies; k \u003d 2, 3 - index characterizing the corresponding numbers of reactive two-terminal networks with resistances

- given equal resistance values of the first and fourth two-terminal networks of the overlapped T-shaped circuit at the given four frequencies.

Figure 1 shows a diagram of a device for generating high-frequency signals (prototype) that implements the prototype method.

Figure 2 shows a block diagram of the proposed device according to p. 2., which implements the proposed generation method according to p. 1 in amplification mode.

Figure 3 shows a block diagram of a matching reactive quadripole included in the proposed device according to claim 2.

In Fig.4. shows a diagram of a reactive two-terminal network that implements the second and third two-terminal networks of a matching reactive four-terminal network in the form of an overlapped T-shaped connection of four two-terminal networks (figure 3).

The prototype device (Fig. 1), which implements the prototype method, contains a direct transmission circuit in the form of a three-pole non-linear element VT-1 connected to a constant voltage source-2, the first matching-filtering device SFU-3 (the first reactive quadripole or the first matching quadripole) and load in the form of an oscillating circuit on the elements L-4, R-5, C(t) - 6. The first SFU-3 is connected between the output electrode of the three-pole non-linear element and the load. Controlled capacitance C(t) implemented by varicap-6 is connected to a source of low-frequency control (information) signal-7. Between the load and the control electrode of the three-pole nonlinear element, a second SFU-9 (the second reactive quadripole or the second matching quadripole) is connected with the first two-terminal-8 connected to its input and the second two-terminal-10 connected to its output with complex resistances in transverse circuits. All this together forms an external feedback loop. The first two-pole-8 is connected to the load. The second two-pole-10 is connected to the control electrode of the three-pole non-linear element.

The principle of operation of the device for generating and modulating high-frequency signals (prototype) that implements the prototype method is as follows.

When the DC voltage source-2 is turned on, due to the abrupt change in amplitude, oscillations occur in the entire circuit, the spectrum of which occupies the entire radio frequency range. The amplitudes of these oscillations decay rapidly. However, due to the presence of external feedback, matching with the help of the first reactive quadripole-3 of the output electrode of the three-pole non-linear element and the load (direct transmission circuit), matching with the feedback circuit (the first two-terminal circuit-8 with complex resistance, the second reactive quadripole-9 and the second two-terminal device-10 with complex resistance) of the load and the control electrode of the three-pole non-linear element, the losses in the circuit L-4, R-5, C(t)-6 are compensated. Due to this, the feedback becomes positive and the conditions for the balance of phases and amplitudes are realized - the conditions for excitation of electromagnetic oscillations. As a result, an oscillation with a frequency equal to the resonant frequency of the oscillatory circuit is fed to the control electrode of the three-pole non-linear element, which initially operates in the amplification mode. The amplitude of this oscillation is amplified until it increases to the level at which the three-pole non-linear element is limited. The stationary regime of generation sets in. In this mode, a change in the capacitance of the varicap C(t) - 6 under the action of the control signal of the source-7 leads to a change in the frequency of the generated signal according to the law of the change in the amplitude of this signal.

на заданных частотах генерируемых сигналов (соответствующих заданным значениям амплитуды низкочастотного управляющего сигнала), подключенный к источнику постоянного напряжения (постоянной составляющей) и низкочастотного управляющего сигнала-2 и подсоединенный по высокой частоте по последовательно-параллельной схеме (входы соединены последовательно, а выходы- параллельно) к цепи внешней обратной связи, выполненной в виде произвольного четырехполюсника-14, сформированного в общем случае на двухполюсниках с комплексными сопротивлениями. Четырехполюсник-14 тоже характеризуется известными значениями элементов смешанной матрицы

на заданных частотах (m = 1, 2 - номер частоты). Трехполюсный нелинейный элемент и цепь обратной связи как единое целое каскадно включены между двухполюсником с сопротивлением

на заданных частотах, имитирующим сопротивление источника высокочастотных колебаний, возникающих при включении источника постоянного напряжения -2 в момент скачкообразного изменения амплитуды его напряжения в режиме генерации, и входом согласующего реактивного четырехполюсника-12, к выходу которого подключена нагрузка-13 с заданными сопротивлениями

на заданных частотах. Четырехполюсник-12 выполнен в виде перекрытого Т-образного соединения четырех реактивных двухполюсников с сопротивлениями

(фиг.3). Синтез генератора (выбор значений сопротивлений

и схем формирования этих двухполюсников (фиг.4) осуществлен по критерию обеспечения баланса амплитуд и баланса фаз путем реализации равенства нулю знаменателя коэффициента передачи устройства генерации в режиме усиления последовательно на заданных четырех частотах генерируемых сигналов при соответствующих четырех значениях амплитуды низкочастотного управляющего сигнала. В интересах упрощения формул для сопротивлений

сопротивления

выбраны равными друг другу. Выбор сопротивлений четырехполюсника-14 можно осуществлять произвольно или исходя из каких-либо других физических соображений. В данном изобретении значения сопротивлений комплексных двухполюсников четырехполюсника-14 выбираются из условий физической реализуемости. В режиме генерации источник входного высокочастотного сигнала отключается и вместо него устанавливается короткозамыкающая перемычка.The disadvantages of the prototype method and the device for its implementation are described above. The proposed device according to claim 2 (figure 2), which implements the proposed method according to claim 1, contains a three-pole nonlinear element-1 with known mixed matrix elements

at the given frequencies of the generated signals (corresponding to the set values of the amplitude of the low-frequency control signal), connected to a source of direct voltage (DC component) and a low-frequency control signal-2 and connected at high frequency in a series-parallel circuit (the inputs are connected in series, and the outputs are connected in parallel) to the external feedback circuit, made in the form of an arbitrary four-terminal network-14, formed in the general case on two-terminal networks with complex resistances. Quadripole-14 is also characterized by known values of the elements of the mixed matrix

at given frequencies (m = 1, 2 - frequency number). A three-pole non-linear element and a feedback circuit as a whole are cascaded between a two-pole with resistance

at given frequencies, simulating the resistance of a source of high-frequency oscillations that occur when a constant voltage source -2 is turned on at the moment of an abrupt change in the amplitude of its voltage in the generation mode, and the input of a matching reactive quadripole-12, to the output of which a load-13 is connected with given resistances

at given frequencies. The four-pole-12 is made in the form of an overlapped T-shaped connection of four reactive two-terminals with resistances

(figure 3). Generator synthesis (selection of resistance values

and circuits for the formation of these two-terminal networks (figure 4) is carried out according to the criterion of ensuring the balance of amplitudes and phase balance by implementing the equality to zero of the denominator of the transfer coefficient of the generation device in the amplification mode in series at the given four frequencies of the generated signals with the corresponding four values of the amplitude of the low-frequency control signal. In the interest of simplifying the formulas for the resistances

resistance

are chosen equal to each other. The choice of resistances of the quadripole-14 can be carried out arbitrarily or based on some other physical considerations. In this invention, the resistance values of the complex two-terminal networks of the quadripole-14 are selected from the conditions of physical feasibility. In the generation mode, the source of the input high-frequency signal is turned off and a short-circuit jumper is installed instead.

The proposed device operates as follows.

второго и третьего двухполюсников согласующего реактивного четырехполюсника и схем формирования этих двухполюсников обратная связь становится положительной что эквивалентно возникновению в цепи отрицательного сопротивления или проводимости (r₁₁ или r₂₂), которое компенсирует потери во всей цепи последовательно на всех частотах заданной полосы частот при соответствующем изменении амплитуды низкочастотного управляющего сигнала. Поэтому амплитуды колебаний с заданными частотами усиливаются до определенных уровней и затем ограничиваются. Благодаря этому, колебания с заданными четырьмя частотами усиливаются до момента увеличения амплитуд этих колебаний до уровня, при котором амплитуда выходит за пределы квазилинейного участка проходной вольтамперной характеристики. Наступает стационарный режим. Окончательно это приводит к увеличению квазилинейного участка частотной модуляционной характеристики, а в динамике - к изменению частоты генерируемого сигнала по закону изменения амплитуды низкочастотного управляющего сигнала.When the constant voltage source-2 is turned on, due to the abrupt change in amplitude, oscillations occur in the entire circuit, the spectrum of which occupies the entire radio frequency range. The amplitudes of these oscillations decay rapidly. However, due to the presence of external feedback and due to the indicated choice of resistance values

the second and third two-terminal networks of the matching reactive four-terminal network and the formation circuits of these two-terminal networks, the feedback becomes positive, which is equivalent to the appearance in the circuit of negative resistance or conductivity (r ₁₁ or r ₂₂ ), which compensates for losses in the entire circuit in series at all frequencies of a given frequency band with a corresponding change in amplitude low frequency control signal. Therefore, the amplitudes of oscillations with given frequencies are amplified to certain levels and then limited. Due to this, oscillations with given four frequencies are amplified until the amplitude of these oscillations increases to a level at which the amplitude goes beyond the quasi-linear section of the current-voltage characteristic. There comes a stationary mode. Finally, this leads to an increase in the quasi-linear section of the frequency modulation characteristic, and in dynamics - to a change in the frequency of the generated signal according to the law of the change in the amplitude of the low-frequency control signal.

Let us prove the possibility of realizing the indicated properties.

и цепи обратной связи

от частоты, которые можно определить по известным (например, измеренным или рассчитанным) элементам матриц сопротивлений, проводимостей или передачи. Кроме того, элементы матриц параметров трехполюсного нелинейного элемента зависят от амплитуды низкочастотного управляющего сигнала. Таким образом, каждой высокой частоте соответствует определенная амплитуда низкочастотного управляющего сигнала. Для простоты аргументы (частота и амплитуда) опущены. При последовательно-параллельном соединении четырехполюсников элементы их матриц H складываются. Суммарные зависимости элементов матриц Я цепи прямой передачи в виде нелинейного элемента и цепи обратной связи от частоты:

Размерности элементов матрицы H: h₁₁ (сопротивление), h₁₂ (безразмерный), h₂₁ (безразмерный), h₂₂ (проводимость).The dependences of the elements of the mixed matrix H of the three-pole nonlinear element are also initial

and feedback loops

on frequency, which can be determined from known (for example, measured or calculated) elements of impedance, conductance, or transmission matrices. In addition, the elements of the matrix parameters of a three-pole nonlinear element depend on the amplitude of the low-frequency control signal. Thus, each high frequency corresponds to a certain amplitude of the low-frequency control signal. For simplicity, the arguments (frequency and amplitude) are omitted. With a series-parallel connection of quadripoles, the elements of their matrices H are added. The total dependences of the elements of the matrices I of the direct transmission circuit in the form of a nonlinear element and the feedback circuit on frequency:

Dimensions of matrix elements H: h ₁₁ (resistance), h ₁₂ (dimensionless), h ₂₁ (dimensionless), h ₂₂ (conductivity).

The general mixed matrix H of a nonlinear element (VT) and a four-terminal feedback circuit (OS) and the corresponding classical transfer matrix:

where

A reactive quadripole (RF) is characterized by a transmission matrix:

а, b, с, d - элементы классической матрицы передачи.where

a, b, c, d - elements of the classical transfer matrix.

We multiply the transfer matrices (1) and (2). Taking into account the normalization conditions, we obtain the general transmission matrix of the entire device:

Using the known connection of the elements of the scattering matrix with the elements of the classical transfer matrix (Feldshtein A.L., Yavich L.R. Synthesis of four-pole and eight-pole microwave networks. M.: Svyaz, 1971. pp. 34-36) and the transfer matrix (3), taking into account the normalization conditions, we obtain an expression for the generator transfer coefficient in the amplification mode:

где первое слагаемое - это сопротивление z₀ пассивной части генератора; второе слагаемое с учетом матриц передачи (1) и (2) - это входное сопротивление активной части генератора в виде трехполюсного нелинейного элемента со смешанной матрицей (1), нагруженного на входное сопротивление

реактивного четырехполюсника, нагруженного на сопротивление нагрузки z_n. Если это условие возникновения стационарного режима генерации записать в виде другого равенства

то ее можно трактовать как условие баланса амплитуд и баланса фаз 1 - KB = 0 (Гоноровский И.С. Радиотехнические цепи и сигналы - М: «Дрофа»., - 2006, с. 383-401) для эквивалентной цепи с внешней положительной обратной связью. При этом четырехполюсники цепи обратной связи и схемы замещения трехполюсного нелинейного элемента соединяются последовательно-параллельно, а в коэффициенте передачи (4) вместо элементов матрицы H нелинейного элемента необходимо использовать суммы элементов этой матрицы и элементов матрицы Я цепи обратной связи. Для данного вида генератора и частотного модулятора

- коэффициент передачи цепи обратной связи;

a - коэффициент усиления цепи прямой передачи. Возможны и другие варианты представления этих коэффициентов, но для изобретения это не имеет значения. При любых представлениях этих величин равенство нулю коэффициента передачи соответствует условию стационарного режима генерации согласно иммитансному критерию устойчивости и условию баланса амплитуд и баланса фаз.Let us transform the denominator of the transfer coefficient and write it in the form corresponding to the immittance criterion of stability (Kulikovskiy A.A. Stability of active linearized circuits with amplifying devices of a new type. M-L .: GEI, 1962. 192 s):

where the first term is the resistance z ₀ of the passive part of the generator; the second term, taking into account the transfer matrices (1) and (2), is the input resistance of the active part of the generator in the form of a three-pole nonlinear element with a mixed matrix (1), loaded on the input resistance

reactive quadripole loaded with load resistance z _n . If this condition for the emergence of a stationary generation regime is written in the form of another equality

then it can be interpreted as a condition for the balance of amplitudes and balance of phases 1 - KB = 0 (Gonorovsky I.S. Radio circuits and signals - M: "Bud" ., - 2006, p. 383-401) for an equivalent circuit with an external positive feedback connection. In this case, the quadripoles of the feedback circuit and the equivalent circuits of the three-pole nonlinear element are connected in series-parallel, and in the transfer coefficient (4) instead of the elements of the matrix H of the nonlinear element, it is necessary to use the sums of the elements of this matrix and the elements of the matrix R of the feedback circuit. For this type of generator and frequency modulator

- feedback loop transfer coefficient;

a is the gain of the direct transmission circuit. Other representations of these coefficients are also possible, but this does not matter to the invention. For any representation of these quantities, the zero transfer coefficient corresponds to the condition of the stationary generation mode according to the immittance stability criterion and the condition of amplitude balance and phase balance.

We equate the denominator of the transfer coefficient to zero.

We divide the real and imaginary parts in (5) and obtain a system of two algebraic equations:

where

The solution of system (6) has the form of optimal frequency dependences of the relationships between the elements of the classical RF transmission matrix:

where

To find the optimal dependences of the reactive resistances of the two-terminal networks that make up the matching four-terminal network on frequency, it is necessary to choose a typical circuit of the two-terminal network, find its transfer matrix, present its elements in the form (2), substitute the coefficients α, β, γ determined in this way into (6) and solve the resulting system of equations for some two parameters of the reactive matching quadripole. Here is the solution of the synthesis problem for the overlapped T-shaped circuit of the four-terminal network (figure 3):

The implementation of the optimal approximating functions of the frequency dependences of the resistances of two-terminal networks (7) can be carried out in various ways, for example, using the interpolation method by finding the values of the parameters of the selected reactive two-terminal networks, at which their resistances at given frequencies coincide with the optimal ones. The values of the parameters of the remaining two-terminals can be chosen arbitrarily or from the provision of any other conditions. Here is an example of the construction of these two-pole networks for four interpolation frequencies, which were used to synthesize the considered variants of generators.

Parallel oscillatory circuit, connected in parallel with a serial oscillatory circuit (figure 4):

where

At k=2, we have the values of the parameters for the second two-terminal network, and at k = 3 - for the third two-terminal network of the overlapped T-shaped circuit. The index m must be introduced into the notation for other quantities that explicitly depend on the frequency.

The implementation of optimal approximations of the frequency characteristics of the parameters of the matching quadripole (7) and (8) using (9) ensures the implementation of the matching condition, amplitude balance and phase balance sequentially at four given frequencies and four amplitude values of the low-frequency control signal of a given modulation characteristic or a given frequency range , corresponding to the specified range of changes in the amplitude of the low-frequency signal. This allows, with a reasonable choice of the positions of the given frequencies relative to each other ω ₁ - ω ₂ , ω ₁ - ω ₃ , ω ₁ - ω ₄ , ω ₂ - ω ₃ , ω ₂ - ω ₄ , ω ₃ - ω ₄ and the given amplitudes to expand linear section of the modulation characteristic. Finally, in dynamics, this leads to a change in the frequency of the generated signal according to the law of the change in the amplitude of the low-frequency control signal.

The proposed technical solutions have an inventive level, since it does not explicitly follow from the published scientific data and known technical solutions that the declared sequence of operations (execution of the load in the form of the first two-terminal network with complex resistance, implementation of the external feedback circuit in the form of an arbitrary four-terminal network connected in series-parallel with a three-pole non-linear element, the inclusion of a three-pole non-linear element and a feedback circuit as a single node between the second two-terminal with complex resistance, which simulates the resistance of the source of the input high-frequency signal of the generator in the amplification mode, and the input of the reactive quadripole (figure 2), the implementation of the reactive quadripole in the form overlapped T-shaped connection of four reactive two-terminal networks (figure 3), the choice of frequency characteristics of the second and third two-terminal overlapped T-shaped link, in the form of which the reactive four rehpole, the formation of their circuits in the specified form (figure 4), the choice of the values of their parameters from the condition of providing a stationary generation mode sequentially at four frequencies and the corresponding four values of the amplitude of the low-frequency signal, provides in dynamics a change in the frequency of the generated signal according to the law of changing the amplitude of the low-frequency control signal on the enlarged quasi-linear section of the frequency modulation characteristic.

The proposed technical solutions are practically applicable, since for their implementation commercially available three-pole non-linear elements (transistors or lamps), reactive elements formed into the claimed two-terminal reactive circuits (Fig. 4) can be used. The values of the parameters of the inductances and capacitances of these circuits can be uniquely determined using the mathematical expressions given in the claims.

The technical and economic efficiency of the proposed device lies in the sequential provision of the generation of a high-frequency signal in a given frequency band and the corresponding range of variation in the amplitude of the low-frequency control signal due to the choice of circuits and parameter values of two reactive two-terminal networks of a matching quadruple network according to the criterion of sequential provision of phase and amplitude balance conditions, which ensures in dynamics, the change in the frequency of the generated signal according to the law of the change in the amplitude of the low-frequency control signal in an enlarged quasi-linear section of the frequency modulation characteristic for given frequency characteristics of all other two-terminal and quadripole networks.

Claims (24)

1. A method for generating and frequency modulating high-frequency signals based on converting the energy of a DC voltage source into the energy of a high-frequency signal, the interaction of a high-frequency signal with a direct transmission circuit, a three-pole nonlinear element, a reactive quadripole, a load and an external feedback circuit, and the fulfillment of excitation conditions in the form of a balance amplitudes and phase balance, which determine the amplitude and frequency of the generated high-frequency signals, respectively, the conditions for matching the direct transmission circuit with the load and the conditions for matching the load with the control electrode of the three-pole nonlinear element, changing the frequency of the generated oscillations according to the law of changing the amplitude of the low-frequency control signal by correspondingly changing the phase balance, which differs by the fact that the load is performed in the form of the first two-terminal network with complex resistance, an arbitrary four-terminal network connected to t is used as an external feedback circuit three-pole non-linear element in a series-parallel circuit, a three-pole non-linear element and a feedback circuit as a single node are cascaded between the introduced second two-terminal network with a complex resistance, simulating the resistance of the generator signal source in the amplification mode, and the input of a reactive four-terminal network, to the output of which the load is connected, conditions excitations in the form of balance of amplitudes and balance of phases and matching conditions are performed by choosing the dependences of the parameters of the reactive quadripole on frequency from the condition for ensuring the stationary generation mode in the form of equality to zero of the denominator of the transfer coefficient in the gain mode sequentially at all frequencies of a given frequency band with a corresponding change in the amplitude of the low-frequency signal according to the following mathematical expressions:

where

- optimal dependences of the ratios of the corresponding elements of the classical transmission matrix on the frequency in a given frequency band;

- given dependences of the ratios of the corresponding elements of the classical transmission matrix on the frequency in a given frequency band; a, b, c, d - elements of the classical transfer matrix;

- given dependences of the real and imaginary components of the resistance of the source of the input high-frequency signal of the generator in the amplification mode on the frequency in a given frequency band;

- given dependences of the real imaginary component of the load resistance on the frequency in a given frequency band;

- given sums of dependences of the real and imaginary constituent elements of the mixed matrix H of a three-pole nonlinear element on the frequency in a given frequency band with a corresponding change in the amplitude of the low-frequency control signal and the dependencies of the corresponding real and imaginary constituent elements of the mixed matrix H of the external feedback circuit

on the frequency in a given frequency band. 2. A device for generating high-frequency signals, consisting of a constant voltage source and a low-frequency control signal, a direct transmission circuit of a three-pole non-linear element and a reactive four-terminal circuit, a load and an external feedback circuit, characterized in that the load is made in the form of the first two-terminal circuit with a complex resistance, the circuit external feedback is made in the form of an arbitrary four-terminal network connected to a three-pole nonlinear element in a series-parallel circuit, a three-pole nonlinear element and a feedback circuit as a single node are cascaded between the introduced second two-terminal network with a complex resistance, which imitates the resistance of the source of the input high-frequency signal of the generator in the mode amplification, and the input of the reactive two-terminal network, to the output of which the load is connected, the reactive four-terminal network is made in the form of an overlapped T-shaped connection of four reactive two-terminal networks with resistances and

moreover, two-terminals with resistances

formed in the form of parallel connected parallel oscillatory circuit of elements with parameters

and a serial oscillatory circuit of elements with parameters

, and the values of the parameters are determined from the condition of matching according to the criterion of ensuring the stationary mode of generation at four frequencies and the corresponding four values of the amplitude of the low-frequency control signal using the following mathematical expressions:

where

- given values of the real and imaginary components of the resistance of the source of the input high-frequency signal of the generator in the amplification mode at four frequencies ω _m = 2πƒ _m ; m = 1, 2, 3, 4 - frequency number; r _nm , x _nm - given values of the real component of the load resistance at four frequencies;

- the given total values of the real and imaginary constituent elements of the mixed matrix H of the three-pole nonlinear element at the given four frequencies and the given four values of the amplitude of the low-frequency control signal and the corresponding real and imaginary constituent elements of the mixed matrix H of the external feedback circuit

at the given four frequencies; k \u003d 2, 3 - index characterizing the corresponding numbers of reactive two-terminal networks with resistances

- given equal resistance values of the first and fourth two-terminal networks of the overlapped T-shaped circuit at the given four frequencies.

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