Impedance conversion type broadband pulse power load

Abstract

The utility model discloses an impedance conversion type broadband pulse power load. The impedance conversion type broadband pulse power load comprises a load cavity, an output port, a first-layer PCB and a second-layer PCB, wherein the output port is arranged on the load cavity; the first-layer PCB and the second-layer PCB are arranged in the load cavity; four first-stage two-way power combiner units are arranged on the first-layer PCB, and output ports of every two first-stage two-way power combiner units are connected with an input port of one second-stage two-way power combiner on the second-layer PCB through a U-shaped connecting structure; the input port of each first-stage two-path power combiner unit is connected with one matched load resistor; two second-stage two-path power combiner units and a third-stage two-path power combiner unit are arranged on the second-layer PCB; the output ports of the two second-stage two-way power combiner units are connected with the input port of the third-stage two-way power combiner unit through microstrip lines, and the output port of the third-stage two-way power combiner unit is connected with the output port through a microstrip line.

Description

Technical Field

[0001] The utility model belongs to the technical field of radio frequency / load, and particularly relates to an impedance transformation type broadband pulse power load. Background Art

[0002] Dry loads are mainly used to absorb the power of radio frequency or microwave systems. They are fully matched loads connected to the end of the transmission line, absorbing all the power without reflection, such as being used as the end of a transmitter. They can also be used as the matching ports of multi-port microwave devices such as power dividers and directional couplers to ensure the matching of characteristic impedance for accurate measurement.

[0003] With the development of broadband high-power microwave devices, the existing dry loads can no longer meet the usage requirements of broadband high power. Summary of the Utility Model

[0004] Purpose of the utility model: To solve the problem that the existing dry loads can no longer meet the usage requirements of broadband high power, the utility model proposes an impedance transformation type broadband pulse power load.

[0005] Technical solution: An impedance transformation type broadband pulse power load includes: a load cavity, an output port arranged on the load cavity, a first-layer PCB and a second-layer PCB arranged in the load cavity;

[0006] Four first-stage 2-way power combiner units are arranged on the first-layer PCB. The output ports of every two first-stage 2-way power combiner units are connected to the input port of one second-stage 2-way power combiner on the second-layer PCB through a U-shaped connection structure; the input port of each first-stage 2-way power combiner unit is connected to one matching load resistor;

[0007] Two second-stage 2-way power combiner units and one third-stage 2-way power combiner unit are arranged on the second-layer PCB; the output ports of the two second-stage 2-way power combiner units are connected to the input port of the third-stage 2-way power combiner unit through microstrip lines, and the output port of the third-stage 2-way power combiner unit is connected to the output port through microstrip lines.

[0008] Further, the first-stage 2-way power combiner unit, the second-stage 2-way power combiner unit and the third-stage 2-way power combiner unit all achieve 2-way power combination through 10-order impedance transformation.

[0009] Further, the load cavity is composed of an upper cover plate, a middle aluminum cavity and a lower cover plate, and the first-layer PCB and the second-layer PCB are fixed back-to-back on the middle aluminum cavity.

[0010] Further, on the second - layer PCB, metal walls are provided between two second - stage 2 - way power combiners, between two second - stage 2 - way power combiners and the third - stage 2 - way power combiner, and between each microstrip line.

[0011] Beneficial effects: Compared with the prior art, the present utility model has the following advantages:

[0012] (1) The working frequency band width of the broadband pulsed power load of the present utility model reaches 7.5 octaves.

[0013] (2) The broadband pulsed power load of the present utility model adopts a microstrip - line PCB structure, making the structure of the power load compact, with a power capacity greater than 50 kW, and more convenient for processing; and by integrating a matching load resistor, it is convenient to use the broadband pulsed power load, having the advantages of higher efficiency and better consistency.

[0014] (3) The present utility model realizes a relatively wide working frequency through the design of multi - order impedance transformation; this multi - order impedance transformation method can be used in the design of broadband power loads with other octaves such as 3 - octave and 5 - octave.

[0015] (4) The present utility model realizes a 50 - kW power capacity through the design of cascading multiple built - in loads and microstrip lines; this cascading design can be used in the design of broadband power loads with other power capacity levels such as 20 kW and 40 kW.

[0016] (5) The present utility model realizes a 50 - kW power capacity through the design of cascading loads and 2 - way power combiners; this cascading design can be used in the design of broadband power loads with other power capacity levels such as 20 kW and 400 kW. Brief Description of the Drawings

[0017] Figure 1 is the schematic diagram of the principle of the 2 - way PCB combiner for each stage;

[0018] Figure 2 is the overall principle schematic diagram of an impedance - transformation - type broadband pulsed power load proposed by the present utility model;

[0019] Figure 3 is the overall principle schematic diagram of an impedance - transformation - type broadband pulsed power load with 16 loads;

[0020] Figure 4 is the external view of an impedance - transformation - type broadband pulsed power load proposed by the present utility model;

[0021] Figure 5 is the three - dimensional structure schematic diagram of an impedance - transformation - type broadband pulsed power load proposed by the present utility model;

[0022] Figure 6 Schematic diagram of the first layer of PCB of an impedance transformation type broadband pulse power load proposed by the present utility model;

[0023] Figure 7 Schematic diagram of the second layer of PCB of an impedance transformation type broadband pulse power load proposed by the present utility model. Specific implementation manners

[0024] The technical solution of the present utility model will be further elaborated in combination with the accompanying drawings and embodiments.

[0025] Figure 1 The schematic diagram of the principle of the 2-way PCB synthesizer for each stage is shown, and 2-in-1 is realized through 10-order impedance transformation; based on this, an embodiment of the present utility model proposes a 50kW impedance transformation type broadband pulse power load, and the 50kW impedance transformation type broadband pulse power load proposed in this embodiment is based on Figure 2 realized, and it is obtained by cascading 2 layers of PCB and a U-shaped connection structure. Specifically, as Figure 4 and Figure 5 shown, from top to bottom, it successively includes an upper cover plate 1, a second layer of PCB 2, an intermediate aluminum cavity 3, a first layer of PCB 4, and a lower cover plate 5, and a load cavity is formed by the upper cover plate 1, the intermediate aluminum cavity 3, and the lower cover plate 5.

[0026] As Figure 6 shown, on the first layer of PCB 4, four first-stage 2-way power synthesizer units 41 are provided, and each first-stage 2-way power synthesizer unit 41 includes two matching load resistors 42 and an output port; the output ports of the four first-stage 2-way power synthesizer units 41 are connected to the input ports of 2 second-stage 2-way power synthesizer units 21 through a U-shaped connection structure 6; the input ports of the four first-stage 2-way power synthesizer units 41 are respectively connected to 8 matching load resistors 42.

[0027] As Figure 7 shown, on the second layer of PCB 2, two second-stage 2-way power synthesizer units 21 and a third-stage 2-way power synthesizer unit 22 are provided. Each second-stage 2-way power synthesizer unit 21 includes two input ports and an output port, and the third-stage 2-way power synthesizer unit 22 also includes two input ports and an output port.

[0028] The input port of each second-stage 2-way power synthesizer unit 21 is connected to the output ports of the two first-stage 2-way power synthesizer units 41 through a U-shaped connection structure 6; the output ports of the two second-stage 2-way power synthesizer units 21 are connected to the input port of the third-stage 2-way power synthesizer unit 22 through a microstrip line 7, and the output port of the third-stage 2-way power synthesizer unit 22 is connected to the output port 8 of the 50kW impedance conversion type broadband pulse power load through a microstrip line. On the second layer PCB 2, the two second-stage 2-way power synthesizer units 21, the second-stage 2-way power synthesizer unit 21 and the third-stage 2-way power synthesizer unit 22, and the microstrip lines 7 are separated by a thick metal wall 9, which can effectively solve the resonance generated by the microstrip lines between the units at each level.

[0029] In this embodiment, 8 loads and four first-stage 2-way power combiner units are implemented by splitting into two layers of PCB due to the limitation of the external dimensions. If the limitation of the external dimensions in depth is relaxed, it can also be implemented with one layer of PCB. When it is expanded to 16 loads and 8 first-stage 2-way power combiner units, a radial layout can be considered, and the overall solution can still be implemented with a two-layer PCB; you can also refer to the implementation solution of this embodiment, such as Figure 3 As shown, two layers of PCB are added to achieve: the 1st and 2nd layer PCBs contain 8 loads and 4 first-stage 2-way power combiner units respectively; the third layer is four second-stage 2-way power combiner units; the fourth layer is 2 third-stage 2-way power combiner units and 1 fourth-stage 2-way power combiner unit.

[0030] The load cavity proposed in this embodiment is made of aluminum block and is divided into three parts: upper and lower cover plates and a middle aluminum cavity. The output port 8 of the 50kW impedance conversion type broadband pulse power load is located on the side wall of the load cavity; the two layers of PCB boards are fixed "back to back" on the middle aluminum cavity 3 by metal screws, and the air cavity required for the load PCB is realized after the upper and lower cover plates are installed.

[0031] The 50kW impedance-transformed broadband pulse power load proposed in this embodiment can achieve a standing wave ratio of less than 1.3, a power capacity of more than 50kW, and an operating frequency band width of 7.5 times the frequency between the operating frequencies of 100 and 750 MHz. The built-in matching load resistor facilitates the use of the broadband pulse power load, and has the advantages of higher efficiency and better consistency.

[0032] The design method of the 50kW impedance transformation type broadband pulse power load proposed in this embodiment can also be applied to the design of power loads of other frequencies and other multiple frequencies.

[0033] The 50kW impedance-transforming broadband pulse power load proposed in this embodiment, and its design method can also be applied to power loads of other power levels, such as 20kW or 40kW power loads.

Claims

1. An impedance conversion type broadband pulse power load, characterized in that: include: A load cavity, an output port disposed on the load cavity, and a first layer PCB and a second layer PCB disposed in the load cavity; Four first-stage 2-way power combiner units are arranged on the first-layer PCB, and the output ports of every two first-stage 2-way power combiner units are connected to the input port of a second-stage 2-way power combiner on the second-layer PCB through a U-shaped connection structure; the input port of each first-stage 2-way power combiner unit is connected to a matching load resistor; Two second-stage 2-way power combiner units and one third-stage 2-way power combiner unit are provided on the second-layer PCB; The output ports of the two second-stage 2-way power combiner units are connected to the input port of the third-stage 2-way power combiner unit through a microstrip line, and the output port of the third-stage 2-way power combiner unit is connected to the output port through a microstrip line.

2. The impedance-converting broadband pulse power load according to claim 1, characterized in that: The first-stage 2-way power combiner unit, the second-stage 2-way power combiner unit and the third-stage 2-way power combiner unit all achieve 2-way power combination through 10th-order impedance transformation.

3. The impedance-converting broadband pulse power load according to claim 1, characterized in that: The load cavity is composed of an upper cover plate, a middle aluminum cavity and a lower cover plate, and the first layer PCB and the second layer PCB are fixed back to back on the middle aluminum cavity.

4. The impedance-converting broadband pulse power load according to claim 1, characterized in that: On the second layer PCB, metal walls are provided between two second-stage 2-way power combiner units, between two second-stage 2-way power combiner units and a third-stage 2-way power combiner unit, and between each microstrip line.

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