CN107275741A - A kind of new millimeter waveguide radial direction power synthesis circuit - Google Patents

Abstract

The present invention describes a novel millimeter wave waveguide radial power combiner. The combiner uses eight rectangular waveguide Y branches to combine eight fan-shaped waveguide-based power combiners arranged radially into one. Compared with the traditional power combiner based on the circular waveguide radial structure, the power combiner of the present invention has a better performance of branch path port amplitude phase consistency. In addition, the circuit has the characteristics of miniaturization and wide frequency band, and can be used to meet the requirements of mm High-efficiency and high-power combining requirements of wave multi-channel.

Description

A Novel Radial Power Combining Circuit of Millimeter-Wave Waveguides

technical field

The invention relates to the technical field of microwave and millimeter waves, in particular to the technical field of millimeter wave power synthesis.

Background technique

With the in-depth application of microwave and millimeter wave microelectronics technology in the system, the microwave and millimeter wave all-solid-state high-power transmitting system has become the symbol of modern advanced microwave and millimeter wave communication and radar. Generally, there are two main ways to obtain high power of microwave and millimeter waves: vacuum electronic power devices and solid-state power devices. Electro-vacuum devices include traditional klystrons and traveling wave tube power amplifiers. Although they can provide high-power output, they are difficult to realize in the process and cannot be mass-produced. Moreover, the working voltage is very high (tens of kilovolts), and the volume Large, low reliability, short life, low linearity. The above shortcomings limit the application of electric vacuum devices in the field of microwave and millimeter waves. Solid-state devices have low power supply voltage, high reliability, small size, light weight, and convenient use, so the application of solid-state devices is becoming more and more extensive. However, compared with electric vacuum devices, although the process, materials and design level are constantly developing, the output power of a single solid-state device is still limited, and the heat dissipation problem and the limitation of impedance matching problem make it often fail to meet the index requirements for single application, so usually Using multiple devices and using power synthesis technology to achieve the purpose of high power output.

In recent years, microwave and millimeter wave power synthesis technology has been developed rapidly, and various power distribution and synthesis circuits have been proposed and applied one after another. Traditional power combining circuits include Wilkinson power dividers, Lange couplers and branch line couplers, etc. These traditional combining/distributing circuits belong to multi-level combining circuits, and the combining efficiency decreases rapidly as the number of combining channels increases. Efficiency occasions can no longer meet actual needs. In order to solve the problem of low combining efficiency, various new power combining technologies are constantly emerging, among which free-space wave power combining and quasi-optical space power combining have been extensively researched and developed. Free space power combining technology is only suitable for obtaining high power at the point of space power demand. This kind of technology is not convenient to realize the solid-state high power output of standard interface, which is not conducive to the application and promotion of the system; it can realize quasi-optical space power combining technology with standard output port It also faces problems such as low synthesis energy collection efficiency, high-order mode influence in the synthesis network, narrow frequency bandwidth of the synthesis network, and radiation loss. Therefore, waveguide-based spatial power combining technology emerged in the 1990s. The waveguide-based spatial power combining technology has high combining efficiency, relatively wide bandwidth, can effectively prevent radiation loss, has good heat dissipation performance, and has the advantages of simple structure and easy implementation, etc. Insufficient synthesis technology. At the same time, it is not limited by the operating frequency and waveguide size, and works in microwave, millimeter wave and higher submillimeter wave frequency bands, effectively solving the problem of achieving high power output in higher frequency bands.

The waveguide structure has the characteristics of low loss and high power capacity, so in the high-power microwave system and millimeter wave system, the power division/synthesis circuit of the waveguide plays an irreplaceable role. Compared with traditional power division/combination circuits (such as Wilkinson power dividers, branch line couplers, etc.), the waveguide structure has incomparable advantages. The radial waveguide combiner adopts a multi-channel waveguide radial structure, which can realize multi-channel synthesis in the first-level waveguide circuit. It has the characteristics of low loss, multi-branch, and high power capacity. It is a microwave millimeter wave multi-channel high-speed Efficient high power synthetic mesh. The most common radial waveguide power combination is based on circular waveguide radial power combination, which uses the circular symmetry of the circular waveguide TE01 mode to achieve uniform power distribution, but the circular waveguide TE01 mode is the fifth highest mode in the circular waveguide. It needs to be obtained by low-order mode suppression structure. In practical applications, it is difficult to guarantee the purity of the TE01 mode in the circular waveguide, and the impure TE01 mode will deteriorate the power-synthesizing branches of the radial structure of the circular waveguide.

The present invention proposes a new millimeter-wave waveguide radial frame power combiner, which is composed of eight fan-shaped waveguide power combiners and eight rectangular waveguide Y-branches. Therefore, it can be used to realize stable and reliable microwave and millimeter wave multi-channel high-efficiency high-power synthesis.

Contents of the invention

In view of the deficiencies in the prior art, the technical problem to be solved by the present invention is to realize a multi-channel waveguide power combining network based on a radial structure, and to avoid the problem of inconsistency in the amplitude and phase of the ports of the power combining branches of the circular waveguide radial structure.

Fig. 1 is an overall model diagram of the present invention, Fig. 2 is a single fan-shaped waveguide-based power combiner, and Fig. 3 is an eight-way rectangular waveguide E-plane Y branch. As shown in Figure 2, the power combiner based on the fan-shaped waveguide of the present invention mainly includes: a section of 45 ° waveguide radial transmission line, the electromagnetic field is transmitted along the radial direction in the radial waveguide; Protruding fan-shaped stepped short-circuit surface; near the bottom of the radial line of the 45° waveguide, multi-channel rectangular waveguides arranged radially; a 45° fan-shaped waveguide connected to the top of the radial transmission line, the electromagnetic field is transmitted along the axial direction in the fan-shaped waveguide; fan-shaped Waveguide to rectangular waveguide transition structure. N channels of rectangular waveguide TE10 mode signals with equal amplitude and same phase fed in from the rectangular waveguide port of the branch channel are fed into the fan-shaped waveguide through the 45° radial line, and the fan-shaped waveguide TE01 mode is synthesized in the fan-shaped waveguide, and then passed through the fan-shaped to the rectangular waveguide The waveguide transition structure transforms into a rectangular waveguide TE10 mode output.

As shown in Figures 1 and 3, the combiner according to the present invention combines eight radially arranged power combiners based on fan-shaped waveguides into one through eight Y-branches of rectangular waveguides.

In the fan-shaped waveguide-based power combiner of the present invention, one end of the rectangular waveguides arranged in multi-path extends to a 45° radial waveguide, and two adjacent rectangular waveguides share the wide side at the junction; the other end of the rectangular waveguide extends around, And the narrow side gradually increases and reaches the height b of the standard rectangular waveguide, and is connected with the standard rectangular waveguide to form multiple standard rectangular waveguide branches; when the number of branches is greater than 2, the narrow sides of the rectangular waveguide arranged on both sides of the 45° radial waveguide The size should be slightly larger than the rectangular waveguides arranged in the middle part.

In the power combiner of the present invention, the stepped short-circuit surface at the bottom end of the 45° radial waveguide is used to achieve good matching of the waveguide port of the 45° radial waveguide, and the structure and shape of the stepped short-circuit surface can be obtained through electromagnetic field simulation optimization.

The power combiner of the present invention is characterized in that: (1) the number of combining branches is large, theoretically, the power combining with more branch numbers can be realized by increasing the radius R of the radial waveguide at 45° and reducing the height b of the rectangular waveguide at the connection (2) Multi-channel power synthesis is realized by a first-level metal waveguide circuit network, which has the characteristics of low loss (3) High power capacity, usually the power capacity of metal waveguides is higher than other integrated transmission lines. (4) Good amplitude-phase consistency of branch ports. Compared with the TE01 mode of the circular waveguide, the TE01 mode of the sectoral waveguide is a lower order mode in the sectoral waveguide. When the angle between the sectoral waveguide is less than 45°, the TE01 mode of the sectoral waveguide is the main mode of the sectoral waveguide. This avoids the problem of inconsistency in the amplitude and phase of the branch path caused by the impurity of the circular waveguide TE01 mode in the power combination based on the circular waveguide radial architecture.

The idea, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings and implementation examples, so as to fully understand the purpose, characteristics and effects of the present invention.

Description of drawings

Fig. 1 is an overall structural diagram of the power combiner and its embodiment of the present invention.

Fig. 2 is a structure diagram of the fan-based waveguide multiplexer and its embodiment according to the present invention.

Fig. 3 is a structural diagram of the Y branch on the E plane of the eight-way rectangular waveguide of the present invention.

Fig. 4 shows the total port reflection coefficient and the amplitude of each rectangular waveguide branch port-total port transmission coefficient of the embodiment of the present invention.

Fig. 5 is the transmission coefficient phase of each rectangular waveguide branch port-total port according to the embodiment of the present invention.

detailed description

Below in conjunction with accompanying drawing, the embodiment of the present invention is described in detail: present embodiment implements under the premise of the technical scheme of the present invention, has provided detailed implementation and specific operation process, but protection scope of the present invention is not limited to the following the embodiment.

As shown in FIG. 1 , this specific embodiment is a 16-way power combiner based on a radial architecture for an eight millimeter wave band. In the embodiment, the E-plane Y branch of the rectangular waveguide integrates eight radially arranged power combiners based on the fan-shaped waveguide, which is denoted as port 1 . The radius of the fan-shaped waveguide is R=6.8mm, and the dimension a of the wide side of the 16-way tapered rectangular waveguide remains unchanged, which is 7.112mm; the dimension of the narrow side is =2.3mm at the junction, and gradually changes to b=3.556mm. In this way, the size of the 16-way rectangular waveguide port is the same as that of the standard rectangular waveguide BJ320 (7.112mm×3.556mm), which are recorded as ports 2-17 in turn here. The stepped short-circuit surface at the bottom end of the 45° radial waveguide is composed of a step, and the step height h1= 2.5mm, diameter d1=3mm.

Figures 4 and 5 are the effect diagrams of the electrical characteristics of the embodiment of the present invention, and Figure 4 is the reflection coefficient diagram of the total port and the amplitude of the transmission coefficient of each rectangular waveguide branch port-total port, it can be seen that in the 31.5GHz-38.5GH frequency band, The reflection coefficient of the total port is better than -20dB. The amplitude imbalance of the transmission coefficient of the 16-way branch port is less than 0.2dB in the frequency band of 31-38GHz, and the insertion loss is less than 0.2dB. Figure 5 shows the phases of the transmission coefficients from the main port to the 16 branch ports. In the frequency range of 31-38 GHz, the transmission coefficients of each rectangular waveguide branch port-total port have almost the same phase relationship.

It can be seen from the above results that the power combiner of the present invention realizes the multi-channel power combining function in the eight millimeter wave frequency band, and the branch ports of the combiner have good amplitude-phase consistency. It can be seen from the embodiments that the power combiner of the present invention can be used to realize stable and reliable multi-channel high-efficiency and high-power in the millimeter-wave frequency band.

The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make many modifications and changes according to the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning or limited experiments on the basis of the prior art shall be within the scope of protection defined by the claims.

Claims (6)

1. A new radial power distribution/synthesis circuit for millimeter wave guides, characterized in that the power distribution/synthesis circuit is composed of eight radially arranged fan-shaped waveguide-based power synthesis/splitters with eight rectangular waveguide E-plane Y branches constitute. Among them, the power combiner/distributor based on the fan-shaped waveguide mainly includes: a section of 45° waveguide radial transmission line; located at the bottom of the 45° waveguide radial line, the upwardly raised fan-shaped stepped short-circuit surface; near the bottom of the 45° waveguide radial line , a multi-channel rectangular waveguide radially arranged; a 45-degree fan-shaped waveguide connected to a radial transmission line; and a fan-shaped waveguide-to-rectangular waveguide transition structure. 2. According to claim 1, based on the fan-shaped waveguide power synthesis circuit, one end of the rectangular waveguide arranged in multiple paths extends to the 45° radial waveguide, and two adjacent rectangular waveguides share the wide side at the connection; the other end of the rectangular waveguide Extending to the surroundings, and the narrow side gradually increases to reach the standard rectangular waveguide height b, and is connected with the standard rectangular waveguide to form multiple standard rectangular waveguide branches; when the number of branches is greater than 2, the ones arranged on both sides of the 45° radial waveguide The size of the narrow side of the rectangular waveguide should be slightly larger than that of the rectangular waveguides arranged in the middle. As the number of branches increases, the height of the rectangular waveguide at the connection will decrease, and a power combiner with more branches can be manufactured to realize a miniaturized multi-branch power combining network. 3. According to the fan-shaped waveguide power synthesis circuit based on the requirements of claims 1 and 2, it is characterized in that the stepped short-circuit surface at the bottom end of the 45° radial transmission line is composed of multi-stage fan-shaped terraces that protrude inward, and the number of stages, ladders Platform height and platform radius can be optimized according to operating frequency and bandwidth requirements. 4. The fan-shaped waveguide power synthesis circuit based on claims 1 and 2, characterized in that the rectangular waveguide is directly connected with the fan-shaped waveguide to form a transitional structure from the fan-shaped waveguide to the rectangular waveguide, the rectangular waveguide is located at the center of the fan-shaped waveguide, and one end extends to the fan-shaped waveguide Waveguide, the wide side of the rectangular waveguide is parallel to the axis of the fan-shaped waveguide. The other end extends radially outward, the wide side of the rectangular waveguide is the size of a standard waveguide, and the narrow side is optimized under the requirement of ensuring the transmission coefficient. 5. According to claim 1, 2, 3, based on the fan-shaped power synthesis circuit, it is characterized in that the rectangular waveguide TE10 mode signals of N paths fed into the power distribution/combination circuit with equal amplitudes and identical phases pass through a 45° path. The line is fed into the fan-shaped waveguide, and the fan-shaped waveguide TE01 mode is synthesized in the fan-shaped waveguide, and then transformed into the rectangular waveguide TE10 mode output through the fan-shaped to rectangular waveguide transition structure. The electromagnetic field is transmitted in the radial direction in the 45-degree radial waveguide, and is transmitted in the axial direction in the fan-shaped waveguide. 6. The eight-way (three-level) rectangular waveguide E-plane Y branch according to claim 1, characterized in that the eight-way rectangular waveguide Y branch combines eight radially arranged power combiners based on fan-shaped waveguides into one.