High-power Gysel type power combiner

Abstract

The invention discloses a high-power Gysel type power combiner which comprises a plurality of input ends and an output end, each input end is connected with a matching circuit and an absorption load circuit in parallel, the matching circuit is composed of an inductor and a capacitor, the absorption load circuit comprises two radio frequency cable groups which are connected in series, and the radio frequency cable groups are connected in parallel. A connection point of the two radio frequency cable groups is connected with one end of the load resistor, and the other end of the load resistor is grounded; each radio frequency cable group comprises at least one radio frequency cable, the impedance of the whole radio frequency cable group is a characteristic impedance value, and the length of each radio frequency cable is a multiple of the equivalent wavelength of a working center frequency point cable; according to the synthesizer, a matching circuit at an input end is realized by adopting an LC network, an inductor is a hollow-core inductor formed by winding a copper wire, and a capacitor part is realized by adopting a mode of combining a dielectric capacitor and a high-voltage ceramic capacitor; an absorption load circuit is realized by adopting an equivalent impedance radio frequency cable, the overall occupied space is small, the structure is compact, and the cost is low.

Description

Technical Field

[0001] The present invention relates to the field of communication equipment, and in particular to a high-power Gysel type power synthesizer. Background Art

[0002] In high-power solid-state transmitters, power synthesizers are the core part. There are many types of power distribution / synthesis technologies, generally including Wilkinson, microstrip coupling, balun transformer, T-junction power division, spatial synthesis technology, etc. However, the above synthesis methods are all synthesized in 2N-power synthesis paths, which brings a lot of unnecessary troubles to the technical implementation and cost control of the transmitter. However, the use of Gysel-type power synthesizers can realize power synthesis of any number of paths, greatly improving the design efficiency and the cost performance of the product.

[0003] Under normal power transmission conditions (common in the market ≤2kW), the traditional implementation method can fully meet the requirements. However, as the signal transmission power increases, if broadband power synthesis is required, balun is generally used to achieve power synthesis and distribution. However, the volume of the high permeability and low loss magnetic core used to build the balun circuit will increase with the increase of transmission power, and the weight will also increase. This will bring inconvenience to fixed installation and increase the cost of use. The traditional single manufacturing process is difficult to meet the requirements of signal synthesis at ultra-high power. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a high-power Gysel type power combiner suitable for high power, which occupies a small space, has a compact structure, is convenient to design and assemble, and has low cost.

[0005] In order to achieve the above-mentioned purpose, the present invention provides a high-power Gysel type power synthesizer, including multiple input ends and one output end, each input end is connected in parallel with a matching circuit and an absorption load circuit, wherein the matching circuit is composed of an inductor and a capacitor, and the absorption load circuit includes two series-connected radio frequency cable groups, the connection point of the two radio frequency cable groups is connected to one end of a load resistor, and the other end of the load resistor is grounded; each radio frequency cable group includes at least one radio frequency cable, the impedance of the entire radio frequency cable group is a characteristic impedance value, and the length of each radio frequency cable is a multiple of the equivalent wavelength of the cable at the working center frequency point.

[0006] Optionally, the matching circuit includes a first inductor and a second inductor connected in series, and a connection point between the first inductor and the second inductor is connected to four capacitors connected end to end, wherein two capacitors connected to the connection point are dielectric capacitors, and the other two are high-voltage ceramic capacitors.

[0007] Optionally, an outer skin of the radio frequency cable is grounded.

[0008] Optionally, the absorption load circuit is also connected to a harmonic suppression circuit.

[0009] Optionally, the harmonic suppression circuit includes an RF cable group, one end of the RF cable group is connected to the absorption load circuit, and the other end is grounded, the RF cable group includes at least one RF cable, the impedance of the entire RF cable group is a characteristic impedance value, and the length of the RF cable is a multiple of the equivalent wavelength of the cable at the working center frequency point.

[0010] Optionally, an output matching circuit is connected between the matching circuit and the output end.

[0011] Optionally, the output matching circuit includes an RF cable group, one end of the RF cable group is connected to the absorption load circuit, and the other end is connected to the output end, the RF cable group includes at least one RF cable, the impedance of the entire RF cable group is a characteristic impedance value, and the length of the RF cable is a multiple of the equivalent wavelength of the cable at the working center frequency point.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows: the matching circuit at the input end of the synthesizer is implemented by an LC network, wherein the inductor is an air-core inductor wound with copper wire, and the capacitor part is implemented by a combination of a dielectric capacitor and a high-voltage ceramic capacitor; the absorption load circuit is implemented by an equivalent impedance radio frequency cable, the overall space occupation is small, the structure is compact, the design and assembly are convenient, and the cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a circuit diagram of a high-power Gysel type power combiner provided by the present invention; Figure 2 is a circuit diagram of a matching circuit provided by the present invention; Figure 3 This is a simulation result diagram of a high-power Gysel type power combiner provided by the present invention; Figure 4 It is a circuit diagram of another high-power Gysel type power combiner provided by the present invention; Figure 5 This is a simulation result diagram of another high-power Gysel type power combiner provided by the present invention. DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0016] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0017] In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above words have no special meaning and cannot be understood as limiting the scope of protection of this application. In addition, although the terms used in this application are selected from well-known and commonly used terms, some terms mentioned in the specification of this application may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article. In addition, it is required to understand this application not only by the actual terms used, but also by the meaning implied by each term.

[0018] Reference Figure 1 This embodiment provides a high-power Gysel type power combiner, including six input terminals (P2-P7) and an output terminal P1, each input terminal is connected in parallel with a matching circuit (S1-S6) and an absorption load circuit, and the matching circuit is composed of a capacitor and an inductor. Specifically, Figure 2 As shown, the matching circuit includes a first inductor L1 and a second inductor L2 connected in series, and a connection point between the first inductor L1 and the second inductor L2 is connected to four capacitors C1 - C4 connected end to end.

[0019] It should be noted that, in this embodiment, the inductor L1 and the inductor L2 are hollow inductors wound with large diameter copper wires, the capacitors C1 and C2 connected at the connection points are dielectric capacitors, and the other two are high voltage ceramic capacitors.

[0020] In practical applications, the size of the specific dielectric capacitor can be simulated in a certain frequency range so that the dielectric circuit pattern can completely approximate the use characteristics of the lumped parameter capacitor, and the predetermined value can be achieved by adjusting the size of the PCB pattern. The PCB circuit is designed with a dielectric board with high thermal conductivity, fast heat dissipation, stable dielectric constant, low thermal expansion coefficient, and large surface insulation resistance. The equivalent capacitor formed by such a circuit pattern has a higher withstand power and withstand voltage characteristics than traditional capacitors, and is particularly suitable for signal distribution / synthesis with high peak power.

[0021] In this embodiment, since the negative absorption load circuit of each input end is the same, the absorption load circuit of the first input end P2 is taken as an example. The absorption load circuit includes a RF cable group T1 and a RF cable group T2 connected in series. The connection point of the RF cable group T1 and the RF cable group T2 is connected to one end of the load resistor R1, and the other end of the load resistor R1 is grounded; each RF cable group includes at least one RF cable, and the impedance of the entire RF cable group is a characteristic impedance value, which is generally 50Ω in microwave, GSM, WCDMA and other systems. The length of each RF cable is a multiple of the equivalent wavelength of the cable at the working center frequency point, which is determined according to the design requirements of the entire power synthesizer, and is generally one of λ / 8, λ / 4, λ / 2, and λ.

[0022] In actual application, since the impedance value of the selected cable is not necessarily exactly equal to the characteristic impedance value of the system, the characteristic impedance value of the system can be achieved by connecting multiple cables in parallel to form an RF cable group. For example, if the characteristic impedance value requirement is 25Ω and the selected cable impedance value is 50, the system requirement can be achieved by connecting two cables of the same length in parallel.

[0023] In this embodiment, an output matching circuit is connected between the matching circuit and the output end P1, and the output matching circuit includes an RF cable group T3, one end of the RF cable group T3 is connected to the absorption load circuit, and the other end is grounded. The RF cable includes at least one RF cable, and the impedance of the entire RF cable group is a characteristic impedance value. The length of the RF cable is a multiple of the equivalent wavelength of the cable at the working center frequency point.

[0024] Figure 3 This is a simulation result diagram of a high-power Gysel type power combiner provided by this embodiment, in which the horizontal axis is the operating frequency and the vertical axis is the equivalent reflection coefficient value when the power amplifier is working. It can be seen from the figure that the high-power combiner level provided by this embodiment can fully meet the design requirements.

[0025] like Figure 4 As shown, this embodiment also provides another high-power Gysel type power combiner, which is different from the above embodiment in that a harmonic suppression circuit is also connected to the absorption load circuit. The harmonics of the absorption load circuit are suppressed by the harmonic suppression circuit. Specifically, in this embodiment, the harmonic suppression circuit includes a radio frequency cable group T4, one end of which is connected to the absorption load circuit and the other end is grounded. The radio frequency cable group T4 is the same as the radio frequency cable group T1 in the above embodiment, including at least one radio frequency cable. The impedance of the entire radio frequency cable group is a characteristic impedance value, which is generally 50Ω in microwave, GSM, WCDMA and other systems. The length of each radio frequency cable is a multiple of the equivalent wavelength of the cable at the working center frequency point, which is determined according to the design requirements of the entire power combiner, and is generally one of λ / 8, λ / 4, λ / 2, and λ. This high-power combiner suppresses harmonics by adding a simple radio frequency cable group, and has a simple structure and occupies a small space.

[0026] Reference Figure 5 , Figure 5 This is a comparison diagram of simulation results of a high-power synthesizer with a harmonic suppression circuit added to the embodiment. In the figure, the ordinate is the equivalent reflection coefficient value when the power amplifier is working. It can be seen from the figure that after adding the harmonic suppression circuit composed of the RF cable group, the second harmonic suppression capability of the entire synthesizer is increased by about 15dB, the suppression effect is obvious, and there is a significant improvement.

[0027] The high-power Gysel type power synthesizer provided in this embodiment combines distributed parameter circuits with lumped elements and introduces RF cables to achieve impedance matching. The special matching model solves the waste of space and performance brought by traditional circuits for multi-level signal synthesis and the difficulty of manufacturing devices under ultra-high power. It is easy to assemble, saves costs, has a more compact structure, and has a higher transmission power (according to actual use results, it is greater than 30kW), with an insertion loss as low as 0.4 dB, which is more conducive to ultra-high power synthesis of any signal energy.

[0028] The above description is only an implementation mode of the present invention, and does not limit the protection scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention description and drawings, or directly or indirectly applied in other related technical fields, are also included in the protection scope of the present invention.

Claims

1. A high-power Gysel type power combiner, characterized in that: It includes multiple input ends and one output end, each input end is connected in parallel with a matching circuit and an absorption load circuit, wherein the matching circuit is composed of an inductor and a capacitor, and the absorption load circuit includes two RF cable groups connected in series, the connection point of the two RF cable groups is connected to one end of the load resistor, and the other end of the load resistor is grounded; each RF cable group includes at least one RF cable, the impedance of the entire RF cable group is a characteristic impedance value, and the length of each RF cable is a multiple of the cable equivalent wavelength at the working center frequency point.

2. The high-power Gysel type power combiner according to claim 1, characterized in that The matching circuit includes a first inductor and a second inductor connected in series, and a connection point between the first inductor and the second inductor is connected to four capacitors connected end to end, wherein two capacitors connected to the connection point are dielectric capacitors, and the other two are high-voltage ceramic capacitors.

3. The high-power Gysel type power combiner according to claim 1, characterized in that: The outer skin of the radio frequency cable is grounded.

4. The high-power Gysel type power combiner according to claim 1, characterized in that: The absorption load circuit is also connected to a harmonic suppression circuit.

5. The high-power Gysel type power combiner according to claim 4, characterized in that: The harmonic suppression circuit includes a radio frequency cable group, one end of which is connected to the absorption load circuit and the other end is grounded. The radio frequency cable group includes at least one radio frequency cable. The impedance of the entire radio frequency cable group is a characteristic impedance value. The length of the radio frequency cable is a multiple of the equivalent wavelength of the cable at the working center frequency point.

6. The high-power Gysel type power combiner according to claim 1, characterized in that: An output matching circuit is connected between the matching circuit and the output end.

7. The high-power Gysel type power combiner according to claim 6, characterized in that: The output matching circuit includes a radio frequency cable group, one end of the radio frequency cable group is connected to the absorption load circuit, and the other end is connected to the output end. The radio frequency cable group includes at least one radio frequency cable, the impedance of the entire radio frequency cable group is a characteristic impedance value, and the length of the radio frequency cable is a multiple of the equivalent wavelength of the cable at the working center frequency point.

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