Double-circuit parametric podsiluvach. Napіvprovіdnikovі parametrical pіdsilyuvаchі Parametric pіdsilyuvach principle of operation

From the front paragraph, it is clear that introducing a changeable capacitance or inductance into the kolyalny circuit, it is possible, with a viable law, to change the parameter to increase the kolivan. the simplest scheme of a single-circuit parametric pilot with a variable capacitance is shown in fig. 10.14 a. The non-linear capacity is measured under the injection of two voltages: the signal one with the frequency and the pumping one with the frequency.

Separate capacitors protect the pumping generator and dzherelo signal in the form of a constant voltage, vicorated to establish a working point on the capacitance-voltage characteristics of the varicap. The blocking choke blocking the way in the lansyug dzherela strum in high frequency.

Let's take a look at the back of the robotic mode of the pilot with the exact dotrimann mind. In this, the so-called synchronous mode, the combination frequency sleep - changes with the frequency so that in the circuit there is only current at the frequency. Replacement scheme for synchronous mode shown in fig. 10.14, b

Mal. 10.14. Single-loop parametric substation (a) and substitution scheme (b)

The symbol denotes the sum of the capacitance of the capacitor to the circuit and the average capacitance of the varicap constant voltage ).

For simplicity, the analysis was carried out by the EPC signal, inclusions in the circuit in sequence, replacements in fig. 10.15 with a stream generator, connected in parallel to the circuit and shunting the internal conductivity G. The voltage conductivity includes also the conductivity, which induces external tension in the elements of the circuit. Shunting the conductivity of the negative conductivity changes the total conductivity and in this way increases the quality factor of the circuit. See the effect of strength.

Let's add a measure for the gain coefficient in view of the tension of the signal at the output of the signal to the maximum tension, as it can be taken for the presence of the parametric modulation. As you can see, the maximum tension, which is seen in the conduction of tension (with the presence of tension), is reached at the given tension signal

(I - amplitude of the jet generator).

When connected to additional conductivity, the voltage at the output will be, and the strain, which is seen in the conductivity of the voltage,

Svіdsi coefіtsієnt poslennia

Guess what is a negative value.

From this point of view, the mental stamina of the parametric parametric substation is insanely vibrating (in synchronous mode)

critical values ​​of parametric modulation coefficient

de - goodness of the circuit with improvements.

Respectfully, when, i.e., If the parametric modulation compensates, spend only in the strength of the tension one thing or another.

Mal. 10.15. Single-loop parametric podsiluvach (before the diagram in Fig. 10.14, a)

In practice, when the real signal is strong, the phase is not visible, and the frequency can change in a real smoothness, it is impossible to reach the synchronous mode. Let the frequency of the signal be not exactly a, de - small difference, so do not go out of the gap of the kolivalny contour. The same combina- tional frequency will be sleep -) With this in the smooth circuit, two corollaries are detected: one with a frequency (blue signal) and another with a frequency (combination frequency).

The spivvіdnoshennia between the amplitudes of the designations of the two kolivans lie in the depths of the modulation capacity and magnitude. The report analysis, which is not induced here, shows that with values ​​close to critical [see. (10.42), and apparently small difference Q amplitudes of both waves are approximately the same. The battle is blamed and caused by the cym of the last (pulsation of the amplitude and change of the phase of the resulting colitis). It is possible, however, to show how, with a difference in frequencies, the average for the period of the battle, the intensity of the colivans is greater, lower for the parametric inflow, i.e., in the so-called biharmonious mode, the signal can be strengthened. However, such a mode of robotics is not always acceptable.

In the case of shortcomings, the power of a single-circuit parametric substation, a free scheme is reviewed in the next paragraph.

You can but, without skin trying to think about it, which is a strength.

We can't do it with electric coli without putting pressure on it. The strength of the stabbing will give rise to a great amplitude, their energy will increase. Too much energy cannot be blamed for nothing. Vіn is guilty of buti introductions zzovnі.

So it's true and it seems. A podsiluvach can’t work without eating, without introducing new energy, and the energy is due to be introduced into the system so that the currents in the electric coli have become stronger. The introduction of energy is due to be in time with the colivans, otherwise, the coli can not be increased, but drowned out.

Up to new types of subsidiaries are known as parametric subsidiaries. Get to know their work.

The kolyvalny circuit is composed of coils of inductance and capacitor. The values ​​of inductance and capacitance are one of the parameters of the circuit. Let's guess why the voltage on the capacitor is increased when it is brought up to a new charge. It's more expensive:

de i - voltage on the capacitor; q - iogo charge, and С - iogo єmnіst.

The voltage is directly proportional to the magnitude of the charge and wrapped in proportion to the capacitance of the capacitor. From this point of view, it is clear that in order to increase the voltage on the capacitor, it is necessary to increase the charge, i.e., to support the additional portion of electricity. What can be done with the help of a way to change the capacitance of the capacitor.

If there is an electrical surge in the circuit, then the charge i, also, the voltage on the capacitor changes sinusoidally. Twice during the period, the charge on the capacitor plates will be the largest.

And what happens if we change the capacitance of the capacitor in qi moments? The charge of the capacitor does not seem to change, but the voltage on the capacitor increases at the same time, at the same time the capacity of the capacitor has changed.

And the increase in the voltage on the capacitor means the increase in the amplitude of the surge, its strength. In this way, for the strengthening of the current in the circuit, it is possible at the moment of the largest charge of the capacitor to change its capacitance, and then, at the moment of the full discharge of the capacitor, turn the capacitance of the capacitor to its first magnitude. Twice for a long period of coliving, it is possible to increase the capacity and 2 times turn it to the cob value. Robity is required in time with oscillations - exactly at the moments of the greatest charge and the total discharge - and in phase with them - change at the moments of the total charge and increase at the moments of the total discharge.

Koristuyuchis in this way, it is possible to strengthen the colivannya in the contour. So, as a way to change one of the parameters of the contour, such a way, having taken the nameparametric reinforcement.

Naturally, there is no strength here without spending energy. In the condenser between the plates there is an electric field, and in order to open the plates, it is necessary to spend the given energy (which is more expensive.

Tsya energy increases the field of the capacitor, after which the voltage increases on the new one. At moment Povny rozryadu capacitor zbіlshennya Yogo єmnostі to pochatkovoї quantities not suprovodzhuvatimetsya povіdomlennyam Yomou whether yakoї dodatkovoї energії so yak zblizhennya plates not zustrіchav protidії field yak vіdsutnє (іnshogo genus vtrati energії on vіdnovlennya pochatkovoї єmnostі capacitor mi vrahovuєmo for simplicity).

Practically, the construction of a parametric substation does not represent a particular complexity. For the purpose of measuring, you can speed up, for example, with a conductor diode. The diode has a locking ball, in which there are daily loads of charges. This ball is located between the balls of different conductivity. In this rank, the diode is essentially a capacitor. Vіdstan mіzh "plates" of the second capacitor, i.e., the tovshchina of the locking ball, lie in the form of the sign i of the magnitude of the voltage in both balls. When the voltage is applied in the “direct” straight line, the torso of the ball changes, when the voltage is applied, the turning value will not increase. By changing the voltage on the balls of the diode, you can change the capacity of the “capacitor”, for example, the diode. The diode is a “capacitor of change of capacity” for any change of capacity it can be controlled by the same pumps, which require power, and the power generation is taken from the generator, which is often called a pumping generator.

Increased amplitude of coliving, their strength cannot be infinite. After the reach of the singing intermediary, it is more likely to generate colivanya - to transform into a parametric generator.

Modern diodes allow parametric pidsiluvacs to work on the arch high frequencies- up to ten thousand megahertz.parametric subsidiariescharacterized by even small wet noises. If a certain negative sound is applied to the locking ball, then any charges will be in this ball practically daily and the noise will increase to an insignificant value.

Yak, having respected, singsongly, a reader, in parametric pods, it is already richly sleepy with regenerative pods. This similarity stretches further. It is possible to attach a kind of "super-regenerative receivers" of parametric subsidiaries. The principles of development of superparametric and superregenerative devices for subsidiaries are essentially analogous. The parametric substation is equal to the number of times for a second to be brought to generation, as it is immediately extinguished (this is how the super-regenerator works itself). The parametric super-regenerator allows the intensity of the signal to be intensified in certain fluctuations in tens of millions of times.

The principle diagram of a two-frequency orb, as it is often called yoga, a two-circuit subsidyuvach is shown in fig. 10.16. The first, signal, circuit is tuned to the central frequency of the signal spectrum (resonant frequency), and the other, “idle”, circuit is tuned to the frequency of the signal, it is strongly blown into the air.

The pumping frequency is chosen from your mind

(10.43)

When choosing a frequency, you should be aware that the frequency of the signal should be within the range of transparency of the auxiliary circuit. Ale combinatsiyna frequency is to blame for the position of the working smugoy signal circuit.

When vikonannі tsikh minds on the signal circuit, you will use only one frequency voltage, and on the additional circuit - frequencies. In respect of the amplitudes of the voltages, small in the porosity, it is possible to replace the non-linear capacitance, together with the pumping generator, linear parametric capacitance, which changes with frequency, as was discussed in § 10.5.

Mal. 10.16. Dual-frequency parametric podsiluvach

Todi under the influence of the voltage to the signal in the lance of the changeable capacity of the wine (crym of other warehouses, so as not to become in this interest) strum

[Cm. 10.36)]. Here.

On the support of the idle circuit, the jet creates a voltage drop

Equivalent to EPC, which is added to the capacity of C, we write it down as in § 8.16 [see. (8.99)], in the form

Combination current of exchanges with EPC, by analogy with viraz (10.44) will be

Respectfully, the pumping phase and frequency (when natural expression (10.45) is daily.

With the improvement of the induced spіvvіdnoshnya for the rest of the fidelity can be written in the form

Like Bachimo, according to the extension to the signal circuit, the non-linear capacity at the same time as the pumping generator and the idle circuit can be replaced by a conductivity

Complex amplitude of the strum

The complex amplitude of the voltage on the signal circuit

(10.46)

de - function complex-obtained function

For the resonance, if later, the support of the additional contour will be and the formula (10.46) looks like

On the substitution scheme, presented in fig. 10.17, elements, roztashovanі zlіva vіd dashed іnї, vіdpіdavlyayut podsilyuvacha signal circuit, and right-handed - non-linear capacity at the same time with additional control. Otriman's scheme essentially works with the scheme of a single-circuit substation (div. Fig. 10.15). The difference is less in the way of designating the equivalent of negative conductivity.

Details, related to the designation of combinatorial coliving and guidance with the method of radiating respect to the advances of the double-circuit pilot:

a) equivalent negative conductivity, and also, if there is more pressure, do not lie in the phase of the pumping voltage.

b) not necessary

Offenses about the power of the two contour pumps are explained by the fact that the same phase of the combination struma is pronounced (10.45), which indicates the nature of the equivalent conductivity in essence, the difference in the phases of the pumping voltage. The first of them can see a friend (without urakhuvannya). When approved, the difference drops, and the retail frequency in any case changes with the frequency of the signal (scallops).

The coefficient of strength of a double-circuit substation at a resonant frequency can be determined by a factor similar to formula (10.40):

de calculated by the formula (10.46), - conduction of the signal circuit gain.

When the frequency is changed to the signal at the resonant frequency and at the same frequency as the module, the support changes, which leads to a change in the module i, also, the coefficient of strengthening the tension.

Priming on virazі (10.46), you can calculate the frequency response and the smog of the passage of the double-circuit substation.

Umov's stamina of a submissive in this type can be written down in the form

Let's look at the energy balance in the dual-frequency substation in the fallow in the frequency range Do not set the frequency and intensity of the signal at the substation input. So, as the increase in the auxiliary frequency, the module of the negative value increases [see. (10.46)], then it also grows [see (10.48)]. Pressure on the signal at the exit of the patient

To determine the necessary tension of the generator, pumping Pson, as well as tension, is seen in the auxiliary circuit, speeded up by the Manley-Row theorem. On the basis of virase (7.104) it is possible to record the next spivvіdnosheniya:

(The minus sign in the rest of the variance of omissions, so it is obvious that tension is selected from the pumping generator.) Spivv_dnosheniya of tensions is illustrated in Fig. 10.18. From this little one it is clear that there is tightness on the additional contour, greater, lower on the signal one. In this way, in order to increase the frequency of tension and growth, the pressure has risen, which is selected by the pumping generator, changes to the frequency of the frequency. weak signal the main significance may not be the degree of tension, but the increase in tension

For example, for illustrative purposes, we will induce such a butt in a dual-frequency parametric substation.

Let it be necessary to increase the signal strength at frequencies with a spectrum width

Output data of the first (signal) circuit: characteristic opir Om; internal opir dzherela signal, shuntuyuchi circuit; opir vanity.

Output data of another (idle) circuit: resonant frequency; characteristic opir Ohm; opir vanity.

First, calculate the required variation of the varicap capacity, we know the boundary value of the conductivity, which can be connected to the signal circuit when specifying the width of the signal spectrum

The maximum quality factor of the signal circuit (when negative conduction is shunted), obviously, is not guilty of overshooting

With the resulting conductivity shunting the first circuit, the fault is no less

At the end, it is significant that the main gains and shortcomings of the parametric subsidiaries.

An important advantage of the parametric switch is a remarkably low level of noise in pairs with transistor or tube switches. In § 7.3, it was designated that the main dzherel noise in the transistor i lamp supportє shotgun effect, confusion by chaotic transfer of discrete charges of electrons and wires (in transistors). In the parametric modulation, a similar effect can be in the device, which modulates the parameter. For example, changing the capacity of a varicap is due to the movement of electronics and wires. However, the intensity of the flow of electricity in a varicap is much less, lower in transistors or lamps. In the rest, the intensity of the flow signifies without any intermediary tightness of the core signal, which is seen in the vane lance, and in the varicap - only the effect of the modulation of the parameter. The weakening of the injection of the shot effect of the flooring is significant, that in the parametric substation the level of noise is mainly represented by thermal noise. At the link with z zim, it is often necessary to cool the parametric diode to 5 ... 10.

Not a lot of parametric podsiluvach є foldability of rozvyazki lansyugiv pumping and signal.

In the scheme, presented in the little 10.14, but, characteristic of parametric submeters in the meter range, the decoupling is carried out behind the auxiliary variable capacitors and blocking chokes. In dіapazonі microwave on yakih Especially widely zastosovuyutsya parametrichnі pіdsilyuvachі, brought vdavatisya to Velma folding konstruktsіy scho poєdnuє in one vuzlі dvochastotnih kolivalny lantsyug in viglyadі porozhnіh rezonatorіv, varіkap i spetsіalnі Elements rozv'yazki (circulator spryamovany coupler poglinach, zagorodzhuvalny fіltr) . Qi nutrition are examined in special courses.

Let's look at the capacitor with a changeable capacity

,

slow pumping pressure u n(t) = U n cos ( w n t). Let the change in voltage be applied to the capacitor u W(t) = U 1 cos ( w 1 t + j), Todi same strum stock

Thus, in the spectrum of the struma, there are components with frequencies w 1 , w n + w 1 i w n - w 1. The frequencies can be seen for the help of high-quality contours, adjusted to the frequency w 1 i w 2 = w n ± w 1 i po'yazanih zagalnoy non-linear єmnistyu (Fig. 65).

Opir vtrat in the first circuit will be R 1 = R" 1 ||R i(de R i- internal opir dzherela signal). Let this loop of adjustments to a frequency close to the frequency of the signal, i.e. n one " w 1. Vіdpovіdno, other circuit L 2 C 2 R 2 laps per frequency w 2 = w n ± w 1 (n 2 » w 2). We can look at the peaks, if the partial frequencies n 1 i n 2 circuits far away, one view of one so that the sound is small. In this way, the normal frequencies are close to partial (the disruption between partial and secondary normal frequencies is small and we can take into account that the fault lies in the smoothness of the transmission of the circuits, i.e., the skin circuit resonates at its own frequency). In this way, sharply strengthen the contour of its frequency, weaken it otherwise.

When achieving a high quality factor of the contour, the support of the skin contour for frequencies that are far from the th partial frequency is practically equal to zero. In this way, the circuit is less likely to be active in a small frequency region near its partial frequency. In the circuit we examined in the main circuit, the tension is active, it can be seen only at frequencies w 1, and in the supplementary one - at one of the frequencies w 2 = w n ± w 1. In this way, since in the skin contour we can only predict for one frequency, then for these frequencies we can write equal harmonic balance

(7.20)

Let it be in the form of a non-linear capacity of varicaps. Todi, as you see,

.

oskolki u C = u 1 + u n - u 2, also within the framework of the harmonic balance, we are to blame u n = A n cos ( w n t), u 1 = A 1 cos ( w 1 t + y 1), u 2 = A 2 cos( w 2 t + y 2) (phase y 1 i y 2 pumping pressure). Substituting qi virazi in virazi for charge C at frequencies w 1 i w 2:

Which way is equal to the harmonic balance (7.20) with the input of the harmonic signal i 1 = I 1 cos ( w 1 t + j) Dial look:

Trochy is easy qi virazi, vvvshi partial frequencies n 1 i n 2, detuning x 1 i x 2, quality factor Q 1 i Q 2 contours of the podsiluvach:

,  ;  ,  ;

,  .

Todі in tsikh signs equal (7.21) in the future I will look

Otrimane spіvvіdnoshennya can be vykonuvatisya at some point in the hour, that in the next next time in the right and left parts of the coefficients at cos ( w 1 t + y 1) i sin ( w 1 t + y one). Let's put in the right part j = y 1 + (j - y one); ± y 2 = y 1 + (± y 2 - y 1), as well as simple trigonometric transformations of the right part, taken

Squared (7.25) and (7.26)

Guessing that the upper sign is falling w 2 = w n + w 1, and the bottom one w 2 = w n - w 1. Subtracting viraz shows that the amplitude of the parametric booster with low-frequency pumping ( w n = w 2 - w 1) the intensity varies depending on the amplitude of the booster pumping from the high-frequency pumping ( w n = w 2 + w one). Now let's look at the skin of tsikh vipadkіv.

At the first slope (when turning uphill), the exact maximum signal will be within reach as a result of fine tuning of the contours, i.e. x 1 = x 2=0

,  .	(7.29)
Mal. 66. Delayed amplitudes A 1 i A 2 types of pumping amplitude A n with precise adjustment of the contours of the pilot.	On fig. 66 shows fallow A 1 i A 2 types A n with precise adjustment of the contours of the pilot. From the little one it is clear that the amplitude of the pumping in the first circuit is monotonously changing in the world with an increase in the pumping amplitude. In this way, in this case, the signal strength in the first circuit is not received. However, the amplitude of knocking at another circuit is proportional to the amplitude of the input signal at A n< A 0 height with height A n. Therefore, in the system, it is possible to strengthen the frequency conversion uphill, as in the capacity

output signal vikoristovuvaty kolyvannya in another contour pіdsilyuvacha. Such a booster is a non-regenerative parametric booster with a frequency shift uphill. Significantly, the coefficient of yogo strength for the design effort. Under the strength coefficient for tension, we will be able to increase the tension at the exit of the patient to the tension of the input signal, which is seen on the narrowed tension. How to spend the first contour to finish small i R i << R"1, then R one " R i i connected to the input signal i 1 vіddaє vіddaє v uzgodzhen navantazhennya powern 1 = n 2. In this way, the increase in tension due to only the increase in the frequency of quanta, and not their numbers, so the noise of such a supporter is minimal and steady.

Pіdsilyuvach w h s frequency shifting down ( w 2 = w n - w 1) є the most significant regenerative substation and does not give any advantages in pairing with the regenerative mode of a single-circuit substation.

Parametric pіdsiluvаєch pristrіy, scho mіstіt kіlіvalіnі konіkі, in іn іn іn іn іn іn іn іn іt іn іt іnіїnіshny dzherel (generator іnkachuvannya) іnіuіє іnjuєіnієі іnіuієє іnіuієєє іnієє іnієєє і і ​​for rahunok vіdpovіdnoї organіvalії ї kolіvіlії

Distribution of conductors, ferrites and electronic-promenade parametric substation.

Napіvprovіdnikovі parametric pіdsiluvаchі (PPU) due to a number of positive authorities

feasibility of micromine tyurization, etc.) took away the most congestion. The main element of the PPU is a parametric diode, which is a reverse-displacement p-n-transition, inclusions in a secondary order in the kolivna system, to which a constant change and voltage of the pumping generator is applied, which creates a modulation of the capacity. The value of the diode capacitance depending on the applied voltage is described by viraz:

de - contact potential difference;

n is a parameter that characterizes the non-linear power capacity of the capacitance (for normal diodes n = 1/2, for diffuse ones - n = 1/3).

If the pumping voltage is applied to the back-displacement p-n-transition, then the change in the capacity of the diode can be described

de,, - depth of modulation of the capacity at the main harmonics of the pumping frequency.

Due to the non-linear occurrence of the capacitance of the parametric diode, the voltage applied to it can lead to a stream of different combination frequencies

de m, n- tsіlі number, scho zmіnuyuyutsya vіd to.

If the capacity is not possible, then the spread of tension according to the combination frequencies is determined by the Menli Row

de - tightness at the frequency.

It is important to note that Menli-Rowe's performance is based on the law of energy conservation for a parametric power supply.

Naytsіkavіshi vipadki, if the system works on three frequencies - the frequencies of the signal and pumping and one of the combination frequencies. Sound the combination frequency is either a total or a reduced frequency.

We can see the parametric switch, which works on the total frequency, so the combination frequency is the sum of the frequencies

signal i of the pumping generator. Hundreds of kilometers from Menli Row, three frequencies are assigned, which can be imagined as

You can write down

The robotic mode with whichever is non-regenerative, so with. Coefficient of strengthening by sweating from another equal is shown as

This type of parametric substation is poured with a stable moving substation. Їх zastosuvannya intermeddle with them, that with stronger signals in the microwave range, it is important to achieve chimalih coefficients of strength.

Let's look at the butt, if through the non-linear chamber the bells are connected, lashed at frequencies,,.

May be

Sounds ripple through the lance of frequencies, from the point of view of the parametric blast, it is energetically equivalent, the pumping tension of the generator is pumped into the ducts of the lance or, in other words, negative conductivity is introduced both at the frequency of the signal and at the difference frequency.

Also, parametric pods of this type are regenerative.

Fallow in terms of frequencies and resonances can either be in different coliving systems, or else, in one coliving system.

In the first type, the parametric substation is called double-circuit (the contour, adjusted to the frequency of pumping is not reversed), in the other type, it is single-circuit.

The largest width of the double-loop PPU of the double-loop type, the slits on the front of the single-loop PPU do not affect the hard phasing of the frequencies to the signal and pumping and allow the implementation of low noise temperatures in general with good broadband.

Structural diagram of a parametric pidsiluvach can be presented in an offensive look (Fig. 5.9).