A tray-type traveling wave power combiner

Abstract

The application discloses a tray type traveling wave power combiner, which comprises a partition plate and two trays, the partition plate is arranged between the two trays, each tray is provided with a waveguide port on two opposite diagonal corners, each tray is provided with a first PCB plate, the first PCB plate is provided with a radio frequency circuit, the radio frequency circuit is connected with a microstrip probe, the partition plate is provided with two second PCB plates, each second PCB plate faces the first PCB plate, and the second PCB plate is provided with an EBG structure. The application can effectively avoid the influence of resonance on the traveling wave power combiner by arranging the EBG structure PCB plates on the two surfaces of the partition plate facing the radio frequency circuit PCB plate; the resonance of the working frequency band of the traveling wave power combiner is eliminated by arranging the EBG structure PCB plate, the circuit layout of the first PCB plate is not affected, the radio frequency circuit is more compact, the transmission loss is reduced, and the synthesis efficiency of the traveling wave power combiner is improved. The application can be widely applied in the field of power combiners.

Description

Technical Field

[0001] This invention relates to the field of power combiners, and in particular to a tray-type traveling wave power combiner. Background Technology

[0002] Transmission loss and the amplitude-phase characteristics of each stage of the coupling bridge are crucial for achieving high-efficiency traveling-wave power combiners (TWBs). The combining efficiency of a TWB is related to the number of combining paths, transmission loss, and coupling bridge losses. The number of combining paths depends on the system's output power requirements and is often non-negotiable. On the other hand, the insertion loss of the coupling bridge is related to the implementation method of the TWB, which currently relies on microstrip probes for signal coupling. However, optimizing microstrip probes depends on the selection of special materials for their fabrication, a method that is not cost-effective. Therefore, optimizing the combining efficiency of TWBs often focuses on reducing transmission loss.

[0003] Existing technologies generally use microstrip transmission lines as the power supply. The losses of microstrip transmission lines mainly consist of dielectric loss, metallic loss, and radiation loss, among which radiation loss is non-negligible in the millimeter-wave band. Current technologies typically use a metal outer casing as the shielding cavity for microstrip transmission lines to reduce radiation loss. However, the shielding cavity only confines the radiated energy within the cavity; it does not limit the transmission mode. Therefore, this approach does not address the problem of radiation loss at its source.

[0004] Furthermore, when using metal cavities, resonance caused by excessive cavity size must be avoided. Multi-channel traveling-wave power combiners often require independent cavities to shield the power amplifier chip and its peripheral circuitry, necessitating ample space between each amplifier unit for screw installation, thus increasing the overall length of the combiner. Simultaneously, as the spacing between amplifier units increases, the length of the delay lines also increases to ensure equal phase output for each signal. This increased delay line length not only increases transmission loss in the branch containing the delay line but also exacerbates amplitude imbalance, further reducing the combining efficiency of the traveling-wave power combiner. Summary of the Invention

[0005] To address the aforementioned technical problems, the present invention aims to provide a tray-type traveling wave power combiner that avoids resonance in the combiner's operating frequency band, thereby achieving a broadband, compact, and miniaturized traveling wave power combiner.

[0006] The technical solution adopted by this invention to solve its technical problem is:

[0007] A tray-type traveling wave power combiner includes a partition and two trays. The partition is disposed between the two trays. Each tray has waveguide ports on two opposite diagonals. Each tray has a first PCB board with radio frequency (RF) circuitry connected to a microstrip probe. The partition has two second PCB boards facing the first PCB board. The second PCB boards have an EBG structure.

[0008] Furthermore, the radio frequency circuit includes a power amplifier unit array and a microstrip transmission line, with each power amplifier unit connected to the microstrip probe via the microstrip transmission line.

[0009] Furthermore, the microstrip probe is provided with a matching membrane.

[0010] Furthermore, the tray is centrally symmetrical.

[0011] Furthermore, the EBG structure includes an array of EBG units.

[0012] Furthermore, the EBG unit includes a metal layer, a dielectric layer, and vias. The vias are disposed in the dielectric layer. The metal layer includes a top metal layer and a bottom metal layer. The metal layers are disposed on two surfaces of the dielectric layer connected by the vias. The bottom metal layer is disposed on the surface of the dielectric layer facing the second PCB board.

[0013] Furthermore, the EBG unit also includes an air cavity located on the side of the top metal layer opposite to the dielectric layer.

[0014] The beneficial effects of this invention are:

[0015] The present invention discloses a tray-type traveling wave power combiner. By setting an EBG structure PCB board on two sides of the partition facing the RF circuit PCB board, the influence of resonance on the traveling wave power combiner can be effectively avoided. By setting the EBG structure PCB board to eliminate the resonance in the operating frequency band of the traveling wave power combiner, the circuit layout of the first PCB board will not be affected, making the RF circuit more compact, reducing transmission loss, and improving the combining efficiency of the traveling wave power combiner. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a tray-type traveling wave power synthesizer according to the present invention;

[0017] Figure 2 This is a schematic diagram of the transverse cross-sectional structure of the tray-type traveling wave power synthesizer of the present invention;

[0018] Figure 3This is a schematic diagram of the EBG structure of a tray-type traveling wave power combiner according to the present invention;

[0019] Figure 4 This is a schematic diagram of the EBG unit of a tray-type traveling wave power synthesizer according to the present invention;

[0020] Figure 5 This is a Brillouin diagram of the EBG unit of a tray-type traveling wave power synthesizer according to the present invention;

[0021] Figure 6 This is a schematic diagram of the simulation results of a tray-type traveling wave power synthesizer according to the present invention.

[0022] Among them, 101 is a partition; 102 is a tray; 103 is a first PCB board; 104 is a second PCB board; 105 is a microstrip probe; 106 is a microstrip transmission line; 107 is a matching diaphragm; 401 is an EBG unit; 402 is a dielectric layer; 403 is a via; 404 is a top metal layer; 405 is a bottom metal layer; and 406 is an air cavity. Detailed Implementation

[0023] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings:

[0024] Reference Figure 1 This invention provides a tray-type traveling wave power combiner, including a partition 101 and two trays 102. The partition 101 is disposed between the two trays 102. Each tray 102 has waveguide ports on two opposite diagonals. Each tray has a first PCB board 103. The first PCB board 103 has radio frequency circuitry and microstrip probes 105 connected to it. The partition 101 has two second PCB boards 104, each facing the first PCB board 103. The second PCB board 104 has an EBG structure.

[0025] Electromagnetic waves are input to the tray-type traveling-wave power combiner through a waveguide port and output through another waveguide port on the tray, forming an input waveguide and an output waveguide. The input waveguide is an E-plane waveguide, operating in waveguide transmission mode (TE). 10 Energy is transmitted in a mode of transmission and electromagnetic wave signal is coupled through a microstrip probe 105 and transmitted to the radio frequency circuit.

[0026] Radio frequency (RF) circuits are used to transmit and amplify signals.

[0027] The EBG structure is used to eliminate resonance within the operating frequency band of traveling wave power synthesizers.

[0028] The microstrip probe 105 is used to couple electromagnetic waves to achieve waveguide transmission mode (TE) of electromagnetic waves. 10The conversion between the electromagnetic wave transmission mode (TEM mode) and the microstrip transmission mode (TEM mode) is performed. Specifically, the microstrip probe 105 at one end of the input waveguide realizes the TEM mode conversion of the electromagnetic wave. 10 The conversion from TEM mode transmission mode to TE mode is achieved by a microstrip probe 105 at one end of the output waveguide. 10 Switching between analog and digital transmission modes.

[0029] The microstrip probe 105 is equivalent to a parallel connection of a resistor and an inductor, where the value of the equivalent resistance determines the coupling degree of the microstrip probe 105. The magnitude of the equivalent resistance is related to the area and position of the microstrip probe 105; the larger the area of ​​the microstrip probe 105, the smaller the normalized resistance, and the more energy can be coupled. For an N-channel coupled traveling wave power combiner, the normalized resistance is distributed according to N-i+1, where the channel closest to the waveguide port has i=1. In the embodiments of the present invention, the microstrip probe 105 is square in shape; probes of other shapes can also achieve the same function, all within the protection scope of the present invention.

[0030] By setting up a second PCB board 104 with an EBG structure, so that the second PCB board 104 faces the first PCB board 103, it will not occupy the RF circuit layout space of the first PCB board 103, making the RF circuit design more compact, reducing transmission loss, and improving the synthesis efficiency of the traveling wave power synthesizer.

[0031] As an optional implementation, the radio frequency circuit includes a power amplifier unit array and a microstrip transmission line 106, with each power amplifier unit connected to the microstrip probe 105 via the microstrip transmission line 106.

[0032] Specifically, in the traveling wave power combiner, after the electromagnetic wave enters the input, it is split into multiple signals and coupled through different microstrip probes 105 to achieve TE. 10 The electromagnetic wave signal is converted from TEM mode to TEM mode and transmitted to the power amplifier unit array via microstrip transmission line 106. Each coupling structure is connected to a power amplifier unit to amplify the electromagnetic wave signal. After being amplified by the power amplifier unit array, the electromagnetic wave signal is transmitted through microstrip transmission line 106 to the microstrip probe 105 at one end of the output waveguide, realizing the conversion from TEM mode to TEM mode. 10 The mode conversion of the transmission mode involves feeding the amplified electromagnetic waves into the output waveguide in a symmetrical manner, and then combining them in phase before outputting them.

[0033] As an optional implementation, the microstrip probe 105 is provided with a matching membrane 107.

[0034] The matching diaphragm 107 is used to offset the equivalent inductance of the microstrip probe 105.

[0035] Reference Figure 2 As an optional implementation, the tray 102 is centrally symmetrical.

[0036] Both trays 102 have exactly the same configuration.

[0037] In an embodiment of the present invention, a delay line is provided on the microstrip transmission line 106 for phase compensation.

[0038] As an optional implementation, the EBG structure includes an array of EBG units 401.

[0039] Reference Figure 3 and Figure 4 The EBG unit 401 includes a metal layer, a dielectric layer 402, and a via 403. The via 403 is disposed in the dielectric layer 402. The metal layer includes a top metal layer 404 and a bottom metal layer 405. The metal layer is disposed on two surfaces of the dielectric layer 402 connected by the via 403. The bottom metal layer 405 is disposed on the surface of the dielectric layer 402 facing the second PCB board 104.

[0040] In an embodiment of the present invention, via 403 is metallized.

[0041] As an optional implementation, the EBG unit 401 further includes an air cavity 406, which is located on the side of the top metal layer 404 opposite to the dielectric layer 402.

[0042] By adopting the second PCB board 104 with an EBG structure, metal cavities are not required between the power amplifier units on the first PCB board 103, thus avoiding the occupation of the RF circuit layout space on the first PCB board 103. This makes the RF circuit design more compact, reduces transmission loss, and improves the synthesis efficiency of the traveling wave power synthesizer.

[0043] Specifically, the key function of the EBG structure depends on each EBG unit 401, and each EBG unit 401 forms an array to form the EBG structure. According to Bloch's theorem, the EBG array and the EBG unit 401 have the same bandgap characteristics.

[0044] Reference Figure 5The Brillouin plot of the EBG unit 401 shown is obtained in this embodiment of the invention by solving the characteristic film solver of simulation software. The Brillouin plot of the EBG unit 401 under periodic boundaries is observed to determine the functional characteristics of the EBG unit 401. The horizontal axis of the Brillouin plot represents electromagnetic waves with incident angles of 0–180°, which is proportional to the phase constant. The vertical axis represents the frequency, and the slope is proportional to the phase velocity. When the slope of the Brillouin plot is close to 0, it indicates that electromagnetic waves at the corresponding incident angle are cut off at the corresponding frequency. Figure 5 As shown, the slopes of electromagnetic waves at frequencies of 12.7 GHz and 16.3 GHz are only 0 for all incident angles, and there are no solutions within the range of 12.7–16.3 GHz. Therefore, the bandgap bandwidth of the horizontal axis EBG element of this Brillouin plot is 12.7–16.3 GHz. Furthermore, 12.7 GHz and 16.3 GHz are the upper and lower cutoff frequencies of the electromagnetic bandgap, respectively, implying that there are no field solutions within the electromagnetic bandgap, meaning that there are no electromagnetic waves with any incident angle within the 12.7–16.3 GHz electromagnetic bandgap.

[0045] According to Bloch's theorem, the array of EBG units 401 has the same bandgap characteristics as a single EBG unit. In an embodiment of the present invention, by setting an EBG structure on a PCB board above the radio frequency circuit, the traveling wave power combiner only has the TEM mode during operation, and the microstrip probe 105 cannot couple out other modes, thus achieving the effect of eliminating resonance.

[0046] In an embodiment of the present invention, a tray-type traveling-wave power combiner includes the aforementioned partition 101, tray 102, first PCB board 103, and second PCB board 104. Simulation of the tray-type traveling-wave power combiner yields the following results: Figure 6 As shown in the image above.

[0047] Reference Figure 6 As shown in the figure above, the tray-type traveling-wave power combiner achieves power combining in the range of 12.87–15.46 GHz and eliminates resonance in the range of 12.7–16.3 GHz. Therefore, the second PCB board 104 of the EBG structure provides a sufficiently wide bandgap for the traveling-wave power combiner, covering its operating frequency band, thus eliminating resonant points within the operating frequency band. Furthermore, since the EBG structure addresses resonance through suppression rather than absorption, it exhibits lower insertion loss compared to tray-type traveling-wave power combiners using absorbing materials. Figure 6 As shown in the figure below, the solid line represents the insertion loss of a traveling wave power combiner based on CMT-EBG, while the dashed line represents the insertion loss of a traveling wave power combiner using absorbing materials.

[0048] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A tray-type traveling wave power combiner, characterized by, The tray type row wave power combiner comprises a partition plate and two trays, the partition plate is arranged between the two trays, each tray is provided with a waveguide port at two opposite corners, each tray is provided with a first PCB plate, the first PCB plate is provided with a radio frequency circuit, the radio frequency circuit is connected with a microstrip probe, the partition plate is provided with two second PCB plates, each second PCB plate faces the first PCB plate, and the second PCB plate is provided with an EBG structure. The electromagnetic wave is input into the tray type row wave power combiner through the waveguide port and is output through another waveguide port on the tray to form an input waveguide and an output waveguide; the input waveguide is an E-plane waveguide, energy is transmitted in a TE10 mode waveguide transmission mode, and the electromagnetic wave signal is coupled through the microstrip probe and transmitted to the radio frequency circuit. The radio frequency circuit is used for transmitting and amplifying signals. The microstrip probe is in a square shape and is used for coupling electromagnetic waves to realize conversion between the TE10 mode waveguide transmission mode and the TEM mode microstrip transmission mode of the electromagnetic wave. The EBG structure is used for eliminating resonance in the working frequency band of the row wave power combiner. The EBG structure comprises an array of EBG units. The EBG unit comprises a metal layer, a dielectric layer and a via, the via is arranged in the dielectric layer, the metal layer comprises a top metal layer and a bottom metal layer, the metal layer is arranged on two surfaces of the dielectric layer communicated by the via, and the bottom metal layer is arranged on the surface of the dielectric layer facing the second PCB plate. The EBG unit further comprises an air cavity, and the air cavity is located on the side of the top metal layer away from the dielectric layer. The electromagnetic band gap bandwidth of the EBG structure is 12.7 GHz to 16.3 GHz. The tray type row wave power combiner realizes power combination within 12.87-15.46 GHz and eliminates resonance within 12.7-16.3 GHz.

2. A bladed traveling wave power combiner as recited in claim 1, wherein, The radio frequency circuit comprises a power amplifier unit array and a microstrip transmission line, and each power amplifier unit is connected with the microstrip probe through the microstrip transmission line.

3. A bladed traveling wave power combiner as recited in claim 1, wherein, The microstrip probe is provided with a matching diaphragm.

4. A bladed traveling wave power combiner as recited in claim 2, wherein, The tray is centrally symmetric. The tray is centrally symmetric.

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