DE1541465B1 - Circuit arrangement for the phase control of two transmitters that work in parallel on a single transmitting antenna - Google Patents

Description

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The invention relates to a circuit arrangement for the invention is therefore based on the object

Phase control of two or more on a high one phase control circuit of the aforementioned

Frequency working, by creating a single pilot type that allows two or more

Oscillator controlled transmitter running in parallel on a single transmitter running on high frequency, for example between

Transmitting antenna via a 5 5 and 1000 MHz designed as a ring coupler, operated in parallel in this way

Working coupling circuit, the antenna of which to couple a common antenna that an opti-

feed point diagonally opposite point over time correction of the relative phase shifts of the

a load balancing resistor is connected to earth. RF signals generated by the two transmitters too

In such circuits for parallel coupling with very large phase differences,

from transmitters to a single transmitting antenna, the io This task is achieved in that according to the invention

feeding high frequency waves must be in phase. according to the circuit arrangement for phase control,

In certain cases it can be useful to have several elements that are known per se, with one Coupling transmitters in parallel to a single antenna. Circuit interacts that controls the phase The main advantage here is that the interrupts automatically when the load out probability a random interruption of the 15 constant resistance consumed power before operation the circuit, which only exceeds a certain value in the event of a random equal, and is automatic premature interruption of operation of the coupled transmitter switches on again if this service occurs after the sub-occurrence, is significantly less than in the case of the crime deviates from this predetermined value, Turn of a single transmitter. the circuit with the load balancing resistor

Since the high-frequency 20 stand supplied by the transmitters is connected and the switch-off at the

vectorial connection point between the output of the phase connection in the single antenna

add, the radiated power then has the same and the controlled phase shifter in front of it - A

Maximum when the supplied RF signals decrease in such a way that an optimal correction of the rela- ™

The frequency and phase are completely synchronous. The syn- thetic phase shifts of the two

The chronicity of the frequencies is without difficulty with 25 transmitters generated HF signals even with very large ones

With the help of a single pilot oscilloscope that controls the transmitters,

lators attainable. In the phase control circuit proposed here

In the lower frequency ranges, for example in, it is useful if the phase comparator is off Long-wave and medium-wave range, is a one-time ring circuit, the first of which is both diaoder One-3 ° gonal points to be corrected by hand from time to time on the energy-withdrawing points from the transmitters position usually sufficient to each phase circuit elements via a transmission synchronism to ensure. For higher frequency lines of such length are connected that at ranges, this setting by hand is sufficient, however, the adjustment of the ring circuit connected to these two dials is not sufficient. Experience shows that during the first gonal points injected vibrations of 90 ° to -operating hours of transmitters which are phase-shifted relative to one another, and their two Displacement under the action of thermal dilata- other diagonal points with the anode of a first tions and contractions, changes in the characteristic rectifier diode or with the cathode of a second lines of the tubes etc. can assume 1000 °. Rectifier diode are connected, with the cathode

The coupling 40 necessary for the parallel connection of transmitters, which are to feed one of the first diode with the anode of the second diode, are connected together and are connected to the controlled phase-switching circuits in several execution slides and have long been known through uniformity (communications control voltage according to amplitude and sign Zeitschrift, 11, 1961, pp. 567 to 575). One particular of the off between the two transmitters * embodiment off such a known decoupling passed waves existing phase shift \ development, the bridge referred to as "ring coupler" is pending 45th In this case, it can also be advantageous to represent a designated arrangement, the structure of which will be described in more detail in the one transmission line between the two. It is also known that the relevant diagonal point of the ring circuit and the load on the rectifier diode which is associated with such a ring coupler, a controllable phase-seeing load balancing resistor is a criterion for slide, ζ. B. a line of variable length, in the mutual phase relationship of the ring 5 is looped, which is the additional phase shift coupler feeding signals. between the diagonal

From the German Auslegeschrift 1 004 244 is points of the ring circuit over the two transfers known, when using two parallel supply lines applied energies by 90 ° working Channels assigned to them.

to take a small amount of energy in each case, 55 According to a particularly advantageous embodiment, this Shares of the two inputs of a phase distortion of the phase equator proposed by the invention feed and with the control circuit obtained from it is in the circuit of the load off control signal To control a phase adjuster in such a way as to set equal resistance of the coupling circuit that the phase difference between the switched to anntene measuring instrument, which depends on leading channels maintains a desired value. 60 of the phase-these existing between the two waves known devices, however, allow displacement in this resistance consumed neither alone nor in combination, measures the desired performance. It is from a predetermined evaluate the phase equality of the ring value of the power output by the corresponding coupler Feeding signals automatically produce the pointer deflection of the instrument a light beam or maintain it, especially if the 65 is interrupted, creating a photocell and a relative phase shift from the aforementioned relay the control voltage of the phase shifter of the Reasons when the transmitter is running in very high values, the phase control circuit is interrupted, accepts. Are several by a single pilot frequency gene-

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rator controlled, parallel to a single transmitting antenna a single tone pilot are excited to the equal means several, each with a ring coupler and a unit of frequencies to be established. The comparison of the Coupling amplitudes containing load balancing resistance and the initial regulation of the phases Circuits coupled transmitters are provided, it is done according to the high-frequency stages of the transmitter, Another feature of the invention is advantageous, 5 Since the signal transmitted by the antenna 25 a if the corresponding number of image and sound signals is provided, Phase control circuits each transmitter from one - it is necessary to have two independent from each other control a common transmitter, whose phase is to carry out the loading phase controls, one of which train phase supplies. for the sender of the image signal and the other for the

The drawing lets the phase control circuit after io transmitter of the audio signal is provided. These two phase control circuits are identical to one another, and explain given embodiment in more detail. It the F i g. 2 illustrates an example shown selected embodiment of such a phase control

F i g. 1 is a simplified circuit, partly in block circuit, which, for example, is connected to the image circuits of Fig. shown circuit diagram of the circuit to 15 two transmitters is connected.

parallel coupling of two television transmitters, a single pilot frequency generator 200 is to one

F i g. 2 shows the fixed phase, which is partially executed as a block diagram, connected to the first image transmitter 210

Circuit diagram of a phase control circuit according to the senschieber 201 and to a to the second image transmitter

Invention, 220 switched controlled phase shifter 202 activated

3 and 3a are vector diagrams showing the resolutions. The controlled phase shifter 202 contains The mode of operation of the phase control circuit according to the invention is, for example, one under the name "Varactor" let explain, known semiconductor element, whose capacitance can be identified with

F i g. 4 is a phase diagram showing the operation of a DC control voltage applied here at 209

Explain circuit proposed according to the invention changes and that in the usual way by detuning which suppresses the phase control when the 25 of a parallel resonance circuit of the high frequency

The power amplifier chain delivered to the load balancing resistor acts. In the absence of a control voltage

as a result of the phase difference between the from the phase comparator, the operating point

The signals emitted by the two transmitters are positioned in front of this element in the middle of the linear range

exceeds a certain value. its voltage-capacitance characteristic, and the

In the circuit of Fig. 1, two television transmitters 30 are brought about phase shift is equal to the-

coupled in parallel to a single antenna. The two ones made by the fixed phase shifter

Transmitters 10 and 20 each have an exit 201 entry.

terminal 11 or 21 for the image signal and an output terminal from the two transmitters 210 and 220 12 or 22 for the audio signal. The image signals are present on the two diplexers 213 Outputs of the two transmitters 10 and 20 are two 35 and 223, their further input terminals 212 and 222 Diplexers 13 and 23, which receive the relevant audio signals at their respective output 14. The exit or 24 disconnect the television signals for picture and sound 214 and 224 of the two diplexers are connected to the give the output of the common antenna 25- not shown in this figure ring coupler are send. connected.

The output terminals 14 and 24 of the two di- 40 By means of two probes 211 and 221 a

plexers 13 and 23 are at the diagonal points 26 and 27 a small proportion of those from the transmitters 210 and 220

a decoupling called a ring coupler is removed. These two

bridge connected, depending on the frequencies and ¹ probes are connected to the diagonal points A and B of one

Power to be transmitted from coaxial conductors or ring coupler connected. This connection takes place

Waveguides is constructed. The conductor sections 15, 16 45 via two transmission lines, for example,

and 17 of this ring coupler have a quarter of the axial construction, in such a way that the on

Wavelength of the emitted high frequency and a diagonal point A or B arriving

set lengths, while the conductor section 18 on three signal opposite that at the other diagonal

Quarter of the same wavelength is tuned. The point B or A incoming signal is an additional

Antenna 25 is at the diagonal point 28 and receives a load 50 phase shift by 90 °. To this

Compensating resistance 19 at the diagonal point 29 of the condition must be met, the two transmission

Ring coupler connected. lines deviate from each other by a fixed length,

When the signals arriving at the diagonal points 26 and 27 between the two signals, a phase shift ring circuit, introduces an amplitude exercise of 90 °. In a preferred embodiment and phase match completely, the guidance form contains the one transmission line, all energy is transmitted to the diagonal point 28 as shown in FIG. 2 leads to the probe 221, for example, and emitted by the antenna 25. As a result of the phase reversal taking place in the one controllable phase shifter 225, for example a conductor section 18, the line section is of adjustable length. The value of the phase shift that is then no energy introduced into the load equalization is output in such a manner admittedly 19. The energy 60 emitted to this means that the additional phase shift of 90 ° is therefore basically achieved by the phase inequality between the signals deposited at the diagonal points A and B of the signals supplied by the two transmitters. That way need hang. the position of the probes 211 and 221 and the length So that the coupling of these transmitters with the circuit of the two transmission lines is not set to the FIG. 1 can be made, it must be 65. A disruptive phase shift, which can be introduced by agile that the circuit of the two transmitters of the picture these circuit elements, is signal and the circuit of the two transmitters of the sound by a corresponding setting of the controllable signal each by a single picture pilot and phase shifter 225 eliminated at 90 °.

Depending on the frequency range used, the power output, coaxial or waveguide output to the load compensation resistor, the phase comparison of a quarter of the wavelength between the two transmitters 210 has three sections 203, 204 and 205, their lengths and 220 signals High fre- shift is dependent. This pointer measuring instrument are frequency signals, and a section 206, the 5 of which is a light source, an element sensitive to light emitted by it equal to three quarters of this same wavelength, a relay and usual connection. Assigned to the diagonal points A and B of these ring circuits. The arrangement of this switching circuit to divide the high-frequency energies fed in is such that, for a predetermined one, the sections 205 and 206 are divided into sections 203 and 204 on the one hand and in terms of the output power of the pointer of the measuring device. The light beam interrupted by the 10 instruments and the energies emanating from this at the diagonal points A and B are added to the light-sensitive element vectorially at the diagonal point C and the change in exposure that occurs, the relay becomes at the diagonal point D as a result of the in the ab- that the control voltage of the phase shifter 202 cut 206 phase inversion occurring vectorially from the phase control circuit short-circuits, subtracted from each other. The series-connected diodes 15 F i g. 4 illustrates a phase diagram of 207 and 208 direct this sum or this difference of the signals emitted by the two transmitters to be the same and give to output terminal 209 an equal combination of one which illustrates the mode of operation of the difference between these two voltages according to the invention Circuit arrangement from voltage which controls the phase shifter 202. for phase control and a circuit for sub-Fig. 3 and 3a represent voltage vector diagrams which serve to break this phase control. Assuming the mode of operation described above that the two signals can be explained when starting up the, namely F i g. 3 for the case in which the transmitters are in phase, the two transmitters are phase-adjusted to the controllable phases, and the correction voltage F i g that feeds slider 202 (FIG. 2). 3 a in the opposite case. Zero. Point A of the corresponds to this state

If the two transmitters have the same high frequency phases 25 diagram (φ ₀ = 0). As a result of having slight differences (FIG. 3), the diagonal properties in the operating behavior of the two points A and B of the ring circuit in FIG. 2 in front of the transmitter, the phase shift between their existing high-frequency voltages increases continuously due to the Vek output signals and is achieved after gates Wa and OB represent. The value φ ₁ s 300 ° on the diagonal for a certain time, provided that points C and D of the ring circuit exist, no phase control is effective. This state frequency voltages are then represented by the following point B. To reduce the phase vectors: shift between the two signals on both

. > _k , for example, one tenth of the value that can be

~ QC - O ^ ~ ^ ~ O ^ · ~ of) - ^ ~~ ^^ setting from the outside serves the

-iiy ■ '1/2 "' 35 phase control circuit , which is operated by means of a phase-

"^ comparator output voltage happens which

The amplitudes of these vectors are equal to one another and are applied to the control input of the Pnasenscnieöers 202

and the rectified, | OD \ - \ OC \ is proportional. The real phase shift between the bigna differential voltage is zero, even in the case of an amplitude equality of the two transmitters at terminals 26 and 27 of the ring coupler 15, 40 to 18 (FIG. 1), under the conditions made above

ie even if the vectors ~ oÄ and ~ OB decreased to a value ψ ₂ S 30 ^Q. This one

have different amplitudes. State is indicated by point C in FIG. 4th

If the two transmitters have different radiofrequency As mentioned above, the phase shift has

have quenzphasen (Fig. 3a), the amplitudes between the respective tuden at the terminals 26 and 27 of the vectors ~ ÖC and ~ ÖD are different, and 45 signals applied to the ring coupler an increase the rectified differential voltage is not zero; the polarity and value of the output to the load compensation resistor 19 depend on the direction of power and a corresponding reduction in the output and the size of the phase difference to be corrected according to the antenna 25 (FIG. 1). Deportation. From the diagram according to FIG. 4 it becomes clear that

Such a phase control circuit has a large 50 in the event of a brief interruption of the phase effectiveness, since the gain of the loop control by applying a voltage of 0 volts is large. However, due to the real characteristics of the variable capacitance at the control input of the phase shifter, its range of action between the diode at terminals 26 of the controlled phase shifter and the signals applied to and 27 is very fast from the possibility of a phase shift due to the value φ _ζ s 3U ° goes over to the value <p ₂ s 300 ", tuning of the parallel resonance connected to it - which latter is limited by the circuit illustrated by point B. Around the large phase shift and the complementary angle of 9J ₁ '= -60 ° shifts to If at that moment the variable phase shifter is put back into operation during a phase control that short-circuits the very brief moment in which the 60 phase difference drops to a tenth of its value, causing the load balancing resistor to produce power one real phase inverse it assumes a certain predetermined value. To those around <p ₂ ', the value of which is necessarily smaller than the purpose one with the phase control circuit of φ ₂ and is about -6 °. This state is shown by point D in the diagram as a circuit arrangement combined. This provided, which has a pointer measuring instrument, the 65 type of operation is enabled by two facts, the circuit of the load compensation resistor 19 light. On the one hand, the phase comparator supplies a spandes of the ring coupling connected upstream of the single antenna, the value of which is looped in from the real phase shift Iers. This measuring instrument measures which is dependent between the two signals and which

20th

Polarity depends on the direction of the minimum phase shift, on the other hand it is variable Phase shifter carried out in a known manner so that there is a phase shift in one or the in the other direction, depending on the polarity of the signal applied to its control input.

The circuit according to the invention, which makes a very brief interruption of the phase control, is intended so perform the following operations:

a) measurement of the power delivered to the terminal 29 of the ring coupler 15 to 18 (FIG. 1);

b) Output of a signal when this power exceeds a predetermined value, the one Phase shift corresponds to the absolute value of which is greater than 18 °, which is a phase shift of 180 ° without phase control;

c) application of a voltage of a predetermined level, for example 0 volts, to the control input of the phase shifter 202 by means of this signal (FIG. 2);

d) Reconnection of the phase control after a very short interruption time. Such a circuit can be implemented in various ways according to the prior art. A possible embodiment has been described above ^a5 .

The interruption of the phase control makes itself in the ring coupler of the two transmitters by a rapid reversal of the power transmitted to the transmitter antenna or the load balancing resistor noticeable. This must therefore withstand a great performance for a short moment. For this it is sufficient that the thermal inertia and the dimensions of this load balancing resistor are sufficient and that the feeding coaxial cable can withstand the relevant high-frequency voltage.

In the case of a television transmitter described above, there is a brief picture and synchronization disturbance one that is meaningless, however, since it is only extremely brief, for example about a twenty-fifth lasts a second. For a radio station or for the audio signal of a television station the occurring disturbance is not noticeable to the ear at all.

With a circuit according to the invention, with extremely simple circuit elements, a achieve excellent, practically linear, and largely perfect phase control. The phase control circuit According to the invention can be used for the parallel coupling of transmitters with frequencies can be operated from, for example, 5 to 1000 MHz. The phase control circuit proposed here can in particular reduce the large mutual phase shifts that occur during the first hours of operation Such transmitters occur, with the operation of the phase control by means of the in the circuit constantly check the load balancing resistance of the ring coupler leaves.

Claims (5)

Patent claims: 1.Circuit arrangement for phase control of two transmitters operating at a high frequency, controlled by a single pilot oscillator, which work in parallel on a single transmitting antenna via a coupling circuit designed as a ring coupler, whose point diagonally opposite the antenna connection point is connected to earth via a load balancing resistor, that the circuit arrangement for phase control, consisting of elements known per se, such as the two transmitters (210, 220) each taking a small amount of energy, circuit elements (211, 221) which are connected to the respective inputs (A, B) of a phase comparator, the output of which feeds a controllable phase shifter (202), which in turn lies between the common pilot oscillator (200) and one of the two transmitters (210, 220) , cooperates with a circuit that automatically interrupts the phase control when the power consumed by the load balancing resistor (19) exceeds a predetermined value and it automatically switches it on again when this power has been interrupted does not exceed a predetermined value, the interruption between the output of the phase comparator and the controlled phase shifter (202). 2. Phase control circuit according to claim 1, characterized in that the phase comparator consists of a ring circuit (203 to 206), the first two diagonal points (A, B ) of each of the circuit elements (211, 221) extracting energy from the transmitters (210, 220) are connected via a transmission line of such a length that when the ring circuit is balanced, the vibrations fed to these two diagonal points (A, B) are phase-shifted by 90 °, and their two other diagonal points (D, C) with the anode of a first rectifier diode (208 ) or are connected to the cathode of a second rectifier diode (207), the cathode of the first diode (208) being interconnected with the anode of the second diode and being connected to the controlled phase shifter (202) and controlling it by a direct voltage that follows The amplitude and sign are dependent on the phase shift present between the waves emitted by the two transmitters (210, 220) . 3. Phase control circuit according to claim 2, characterized in that in the one transmission line between the relevant diagonal point (B) of the ring circuit and the associated rectifier diode (221) a controllable phase shifter (225), for. B. a line of variable length is looped. 4. Phase control circuit according to claim 2 or 3, characterized in that a measuring instrument is connected in the circuit of the load balancing resistor (19) of the coupling circuit, which measures the output depending on the phase shift existing between the two waves, wherein from a predetermined value of output power is interrupted by the corresponding pointer deflection of the instrument and the control voltage of the phase shifter (202) of the phase control circuit is interrupted via a photocell and a relay. 5. Phase control circuit according to claims 1 009 517/125 to 3 for several controlled by a single pilot frequency generator, in parallel to a single one Transmitting antenna by means of several, each containing a ring coupler and a load balancing resistor Coupling circuits coupled 10 Transmitter, characterized in that the phase control circuits provided in a corresponding number control each transmitter from a common transmitter whose phase is the reference phase supplies. 1 sheet of drawings