RU2776468C1 - Adder of microwave signals - Google Patents

Abstract

FIELD: microwave technology.

SUBSTANCE: invention relates to microwave technology, in particular, to devices for adding (dividing) microwave signals and can be used for adding (dividing) microwave signals in feeder paths of communication technology and radar devices, television, in measuring technology. In the adder of microwave signals, containing a symmetrical tee, having two outputs (inputs) located on opposite sides of the input (output), connected by transmission lines with the output (input), active resistance included between the lines, an additional microwave transmission line is introduced, connecting active resistance radiator with adder housing. An additional microwave transmission line connecting the active resistance radiator with an external radiator (adder case) is made in the form of a tuning element.

EFFECT: increase in the level of operating power while maintaining good matching and low losses, simplifying the design, increasing the bandwidth of operating frequencies while maintaining a high level of operating power.

3 cl, 1 dwg

Description

The invention relates to microwave technology, in particular, to devices for adding (dividing) microwave signals and can be used for adding (dividing) microwave signals in feeder paths of communication technology and radar devices, television, measuring equipment.

When developing microwave devices, the problem arises of creating a device for adding (dividing) microwave signals to a high level of operating power, with low losses and good matching in a wide frequency range, having small weight and size indicators. In this case, it is necessary that the inputs of the adder be isolated from each other. Isolation of the inputs of the adder (divider) allows the addition (division) of signals, for example, the addition of a microwave signal from several generators when one or more fails.

Addition (division) of the microwave signal can be carried out using a ring bridge (Design of lens, scanning, wide-range antennas and feeder devices, Zhuk MS and Molochkov Yu.B., M., "Energy", 1973). Ring bridges can be made on lines of various types: coaxial, balanced and unbalanced strip lines. The ring bridge contains a body and a conductor installed inside it, made in the form of a closed ring, an output, two inputs installed on opposite sides of the output at a distance equal to a quarter of a wavelength, and a second output located between the inputs at a distance of a quarter of a wavelength from one of the inputs and three quarters from the other, and connected to a matched load.

When connected to two inputs of generators, the microwave signals from them are added, and the failure of one of the generators does not affect the operation of the second. High power signals can be summed in this device, since the power is limited mainly by the power that the matched load can handle.

However, this device has large dimensions. The total length of the middle line of the ring is 1.5λ (Design of lens, scanning, wide-range antennas and feeder devices, Zhuk M.S. and Molochkov Yu.B., M., Energia, 1973).

Another device with which you can add (divide) a microwave signal is a ring divider (adder) (Design and calculation of microwave elements on strip lines, Maloradsky L.G., Yavich L.R., M., "Soviet Radio", 1972), consisting of a symmetrical tee, having an input and 2 outputs located on opposite sides of the input at a distance equal to a quarter of the wavelength, and an active resistance connected at one end to the first output, the other - to the second. The power divider (adder) provides decoupling between the output arms, good matching, low losses and much smaller dimensions, since the total length of the center line is 0.5λ.

However, this device has a low level of operating power, since the use of active resistance designed for high operating power leads to a significant deterioration in parameters due to the presence of parasitic reactances of the resistance (inductance and capacitance of the leads, capacitance formed by the resistive layer and the case, etc.). P.). This is because to increase the operating power it is necessary to use an external radiator, which, as a rule, is connected to the device case.

Another analog, chosen as a prototype due to the similarity of the technical task being performed, is a (adder) divider (UHF signal divider, utility model patent No. 113421 cl. IPC H01R 5/16, publ. having an input, two outputs located on opposite sides of the input at a distance equal to a quarter of a wavelength and an active resistance connected at one end to the first output, the second - to the second, in which two tuning elements are introduced, the first being connected to one output of the active resistance, the second to another output of active resistance.

The use of tuning elements allows the use of resistances mounted on the radiator, designed to scatter a high power signal, which increases the operating power of the device. At the same time, good coordination and low losses are maintained.

However, the disadvantage of this device is the low level of operating power, which may be due to the following reasons:

- the use of a more powerful resistance is limited by the fact that a powerful resistance has such a value of parasitic reactances (primarily capacitance) that it is impossible to obtain good matching and low losses even with the help of tuning elements. An increase in the number of resistors leads to an increase in the area from which heat is removed, but does not allow maintaining good matching and low losses. This is due to the presence of parasitic resistance reactances (primarily capacitance), which add up and whose influence cannot be compensated by using trimmers.

The technical result of the proposed technical solution is to increase the level of operating power while maintaining good matching and low losses.

Another technical result of the proposed technical solution is to simplify the design, increase the operating frequency band while maintaining a high level of operating power.

An additional technical result is an increase in the operating power level, an increase in the isolation between the inputs while maintaining good matching and low losses.

The specified technical result is achieved by the fact that in the microwave signal adder containing a symmetrical tee having two outputs (inputs) located on opposite sides of the input (output), connected by transmission lines to the output (input), the active resistance connected between the lines is introduced an additional microwave transmission line connecting the active resistance radiator with an external radiator having direct (electrical and thermal) contact with the adder case. The body of the adder can be an external radiator that cools all the active resistance (active resistance radiator with a resistive layer installed on it). An additional microwave transmission line allows for remote connection of active resistance (resistance radiator) with an external radiator that has direct contact with the device case.

Another technical result of the proposed technical solution is achieved by the fact that the additional microwave transmission line connecting the active resistance radiator with an external radiator (adder housing) is made in the form of a tuning element.

An additional result is achieved by the fact that the additional microwave transmission line connecting the active resistance radiator with the external radiator (adder case) consists of at least two segments having different wave impedance.

The proposed device has significant differences from the known adders (dividers):

In dividers (patent EP 1017124 A1, patent CN 204243166 U, Fundamentals of designing microwave integrated circuits V.B. Kirilchuk, D.V. Likhachevsky, part 2, Minsk BGUIO, 2012, p. 232, 233), additional microwave lines are introduced , however, these lines are connected to the transmission lines connecting the outputs of the divider with its input. In the claimed device, an additional transmission line is introduced, connecting the active resistance radiator with an external radiator, which has direct contact with the adder housing;

In the divider (adder), taken as a prototype (UHF signal divider, utility model patent No. 113421 class IPC H01R 5/16, publ. 10.02.2012), the active resistance is installed directly on the external radiator;

In the divider (adder) (Microwave signal divider, utility model patent No. 118125 class IPC H01R 5/16, publ. 07/10/2012), active resistance is installed on the radiator through a dielectric (dielectric, installed between the external radiator case and the active resistance case );

In the divider (adder) (UHF signal divider, patent for utility model No. 173580 class IPC H01R 5/16 publ. 08/31/2017), the active resistance is installed directly on the radiator, but a dielectric is introduced installed between the radiator case and the divider case.

Thus, in all considered known adders (dividers), the active resistance is installed on the radiator either directly on the case or through a dielectric.

The use of an additional microwave line, including as a tuning element (loop), is known. In the well-known technical solutions, the cable connects the central conductor of the device to the body of the device through a direct galvanic contact (A.L. Drabkin et al. Antenna-feeder devices, 2nd edition, add. And revised., M., "Sov. Radio", 1974, pp. 462-465). The difference between the proposed technical solution and the known ones is that an additional microwave line connects the active resistance radiator to the adder housing. In the resistance design, the radiator is not galvanically connected to the resistance terminals and through them to the central conductors of the adder. Therefore, in the proposed technical solution there is no direct galvanic connection between the central conductors of the transmission lines connecting the inputs and output of the adder.

In addition, in the proposed technical solution, an additional microwave line serves not only to improve the electrical parameters, but also to remove heat.

Thus, there are no analogues characterized by sets of features identical to all the features of the claimed device. Therefore, the claimed technical solution meets the condition of patentability "novelty".

The claimed technical solution does not follow explicitly from the prior art. Also, the popularity of essential features from the proposed technical solution that affect the achievement of the specified technical result has not been revealed. Therefore, the claimed technical solution meets the condition of patentability "inventive step".

The essence of the invention will be better understood from the description and accompanying drawings.

In FIG. 1 shows a diagram of the proposed device.

The following designations are used in the drawing and in the text:

1 - adder output;

2 - adder input;

3 - adder input;

4 - active resistance;

5 - active resistance radiator;

6 - resistive layer of active resistance;

7 - additional microwave transmission line connecting the active resistance radiator with an external radiator having direct contact with the device case;

8 - body of the adder (external radiator);

9, 10 - segments of an additional microwave transmission line.

The microwave signal adder contains a symmetrical tee, output 1 and two inputs 2, 3, located on opposite sides of output 1, active resistance 4, consisting of a resistance radiator 5 with a resistive layer 6 installed on it, connected between outputs 2, 3, additional Microwave line 7 connecting the active resistance radiator 5 with the adder housing (external radiator) 8, which is usually an external radiator for active resistance 4 (active resistance radiator 5 with a resistive layer 6 installed on it). Additional microwave transmission line 7 is made of a material with high thermal conductivity (for example, copper).

An additional microwave transmission line 7 connecting the active resistance radiator 5 with the body of the adder 8 consists of at least two segments 9,10 having different wave impedance.

The adder (divider) of microwave signals works as follows.

If the device is used as an adder, then this device works as follows:

Provided that the signals received at inputs 2, 3 have the same amplitude and phase, the signals are added and they arrive at output 1.

In the event that the signals received at inputs 2, 3 have different amplitudes and (or) phases, then these signals arrive at output 1 not only through the microwave lines connecting inputs 2, 3 with output 1, but also through active resistance 4 (through the resistive active resistance layer 6). Thus, at each of the outputs 3, 2, the signals are added in antiphase, thereby compensating the reflected signal, that is, decoupling between outputs 2 and 3 is achieved. In this case, half of the power is supplied to outputs 3, 2, and half is dissipated at resistance 4 Equality (in terms of power and phase), and, consequently, full compensation of the reflected signals coming to the outputs 3, 2 can be achieved by tuning elements similar to the tuned elements of the prototype (not shown in Fig. 1).

In the event that the device is used as a divider, then this device works as follows:

The microwave signal received at input 1 is divided equally between two outputs 2, 3, located at a distance equal to a quarter of a wavelength from input 1. The signals at outputs 2, 3 are equal and in phase if outputs 2, 3 are matched. Coordination of outputs 2, 3 is achieved by connecting them to matched loads (not shown in Fig. 1), compensation of parasitic reactances of resistance 4 can be carried out by tuning elements similar to those used in the adder, taken as a prototype (UHF signal divider, utility model patent No. 113421 class IPC H01R 5/16, published on February 10, 2012) (not shown in Fig. 1).

The adder (divider) of microwave signals can be either single-stage or multi-stage (Fundamentals of designing microwave integrated circuits V.B. Kirilchuk, D.V. Likhachevsky, part 2, Minsk BGUIO, 2012, pp. 232, 235).

The heat generated in the resistive layer of active resistance 6 is removed through the active resistance radiator 5 via an additional microwave line 7 to the adder body (external radiator) 8.

The introduction of an additional line 7, which does not have contact with the body at the place where the resistor is installed, connecting the active resistance radiator to the adder body (radiator case) 8, due to its execution from a material with good thermal conductivity, allows you to effectively remove heat from the resistance 4, providing high operating power . At the same time, the implementation of electrical contact of the radiator 5 of the active resistance 4 with the body of the adder 8 through an additional microwave transmission line 7 allows for good matching and low losses, which would be impossible when installing (making electrical contact) active resistance 5 directly on the body of the adder 8.

The use of tuning elements connected at one end to the central conductor of the microwave lines of the adder, and at the other - to the body of the device leads to an increase in signal loss, deterioration in matching in the operating frequency band (A.P. Dorokhov Calculation and design of antenna-feeder devices, publishing house of Kharkov State University , Kharkov, 1960, pp. 319-322). The use of an additional microwave line 7 as a trimmer allows you to do without trimmers similar to trimmers used in the adder, taken as a prototype (UHF signal divider, utility model patent No. 113421 class IPC H01R 5/16, publ. , which simplifies the design, increases the operating frequency band, i.e. reduces signal loss, improves matching while maintaining a high level of operating power in a wide band of operating frequencies.

The implementation of the additional line 7 in the form of two or more segments with different wave impedance, allows you to increase the isolation between the inputs while maintaining a high level of operating power, low signal loss.

Calculations show that the use of the proposed technical solution will increase the level of operating power compared to the microwave signal divider selected as a prototype (Patent for utility model No. 113421 class IPC H01R 5/16, publ. active resistance in the prototype is not connected to the body, not less than 10 times while maintaining good matching and low losses of the microwave signal.

On the date of filing the application, a two-stage microwave adder (divider) of the decimeter wave range was created using a resistance of the R1-2-100 Ohm type, additional tuned elements were not used. The role of tuning elements was performed by an additional line, consisting of 3 segments with different wave impedances. The parameters of an additional microwave line (segments) are determined by the frequency range, active resistance parameters, parameters of the adder transmission lines, etc. It has been experimentally established that the length of the additional microwave line, consisting of 3 segments, is less than the length of the additional microwave line, consisting of the 1st segment. This leads to an additional increase in operating power due to more efficient heat removal from the resistance due to a decrease in the thermal resistance of the additional microwave line.

Comparative tests have shown that the divider has a good match (SWR less than 1.7). Losses in comparison with the microwave adder (divider), made according to the scheme of the prototype, reduced by 4 dB.

When using an additional line in the form of three segments with different impedance, there is an increase in the isolation between the inputs by 5 dB.

The use of the proposed technical solution will increase the level of operating power, increase the isolation between the inputs while maintaining good matching and low losses.

Claims (3)

1. A microwave signal adder containing a symmetrical tee having two outputs located on opposite sides of the input, connected by transmission lines to the output, an active resistance connected between the lines, characterized in that an additional microwave transmission line is introduced connecting the active resistance radiator with an external a radiator having direct contact with the adder case. 2. The adder of microwave signals according to claim 1, characterized in that the additional microwave transmission line connecting the active resistance radiator with the body of the adder is made in the form of a tuning element. 3. The combiner of microwave signals according to claim 1, characterized in that the additional microwave transmission line connecting the active resistance radiator with the adder housing consists of at least two segments having different wave impedance.

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