阅读说明：本技术 基于te103波导模式的双工滤波器 (Duplex filter based on TE103 waveguide mode ) 是由 武永 曾庆生 张言东 陈梦悦 于 2019-12-08 设计创作，主要内容包括：一种基于TE103波导模式的双工滤波器,包括主腔体和盖板,盖板盖在主腔体上构成波导腔体。所述盖板的中心位置设有公共波导口；主腔体的中心位置处设有台阶,台阶在公共波导口于主腔体的投影位置处；主腔体的分为高频率腔体和低频率腔体；高频率腔体和低频率腔体是成两边分布的结构；高频率腔体和低频率腔体通过公共耦合窗耦合,台阶在公共耦合窗内；对于高频率腔体：从左到右依次是高频段波导口、高频率TE103模式的交叉耦合窗、高频率TE103模式耦合窗和高频率TE103模式谐振腔；对于低频率腔体：从右到左依次是低频段波导口、低频率的TE103模式的交叉耦合窗、低频率TE103模式耦合窗和低频率TE103模式谐振腔。(A duplex filter based on TE103 waveguide mode comprises a main cavity and a cover plate, wherein the cover plate covers the main cavity to form a waveguide cavity. A common waveguide port is formed in the center of the cover plate; a step is arranged at the central position of the main cavity, and the step is positioned at the projection position of the common waveguide port on the main cavity; the main cavity is divided into a high-frequency cavity and a low-frequency cavity; the high-frequency cavity and the low-frequency cavity are in a structure with two sides distributed; the high-frequency cavity and the low-frequency cavity are coupled through a common coupling window, and the step is arranged in the common coupling window; for a high frequency cavity: from left to right, a high-frequency band waveguide port, a high-frequency TE103 mode cross coupling window, a high-frequency TE103 mode coupling window and a high-frequency TE103 mode resonant cavity are arranged in sequence; for low frequency cavities: from right to left are the low-band waveguide port, the low-frequency cross-coupling window of the TE103 mode, the low-frequency TE103 mode coupling window, and the low-frequency TE103 mode resonator cavity.)

1. A duplex filter based on TE103 waveguide mode comprises a main cavity (1) and a cover plate (20), wherein the cover plate covers the main cavity to form a waveguide cavity, and is characterized in that a common waveguide port (18) is arranged at the center of the cover plate; a step (2) is arranged at the central position of the main cavity, and the step (2) is arranged at the projection position of the common waveguide port (18) on the main cavity;

the main cavity is divided into a high-frequency cavity and a low-frequency cavity; the high-frequency cavity and the low-frequency cavity are distributed in two sides relative to a straight line l 1; the high-frequency cavity and the low-frequency cavity are coupled through a common coupling window, the step (2) is arranged in the common coupling window, the middle line of the common coupling window is a straight line l1, and the projection of the middle line l2 in the length direction of the step (2) on the common coupling window is superposed with a straight line l 1;

for a high frequency cavity:

a high-frequency band waveguide port (9), a high-frequency TE103 mode cross coupling window (7), a high-frequency TE103 mode coupling window (8) and a high-frequency TE103 mode resonant cavity (6) are arranged from left to right in sequence;

the cavity structure of the high-frequency cavity is as follows: the two U-shaped cavities are arranged in parallel left and right, and the linear cavity is arranged above the two U-shaped cavities;

the left side of the left U-shaped cavity is coupled with the high-frequency band waveguide port (9); the left side of the linear cavity is coupled to the left side of the left U-shaped cavity through a coupling hole, and a cross coupling window (7) of a TE103 mode is arranged beside the coupling hole; the right side of the linear cavity is coupled to the right side of the left U-shaped cavity through a coupling hole, and the coupling hole is a high-frequency TE103 mode coupling window (8);

the connecting edges of the left U-shaped cavity and the right U-shaped cavity extend into the linear cavity, a coupling hole is formed between the connecting edges and the top edge of the linear cavity, and the cavity between the coupling hole and the right edge of the linear cavity is a high-frequency TE103 mode resonant cavity (6);

the right side of the right U-shaped cavity is coupled to the public coupling window, and the right side of the straight cavity is coupled to the right side of the right U-shaped cavity through the coupling hole;

tuning threaded holes penetrating through the main cavity are formed in the side surfaces of the linear cavity, the U-shaped cavities and the coupling holes;

for low frequency cavities:

from right to left, a low-frequency waveguide port (10), a low-frequency TE103 mode cross coupling window (5), a low-frequency TE103 mode coupling window (4) and a low-frequency TE103 mode resonant cavity (3) are arranged in sequence.

2. The duplex filter based on the TE103 waveguide mode according to claim 1, wherein the common waveguide port (18) is a standard BJ320 waveguide port; the high-band waveguide port (9) is a BJ320 high-band waveguide port; the low band waveguide port (10) is a BJ320 low band waveguide port.

3. The duplex filter based on the TE103 waveguide mode of claim 1, wherein the common waveguide port (18) is a common waveguide T-junction.

Technical Field

The invention relates to the field of microwave and millimeter wave communication, in particular to a duplex filter based on a TE103 waveguide mode.

Background

With the continuous progress of communication technology, the traditional communication spectrum resources are more and more tense, and the requirements of people on information services are higher and higher, the traditional communication means can not meet the requirements of people on a rapidly developed information society, and the communication mode basically faces the problems of small communication capacity and low data transmission rate. The solution to these problems requires the development of higher frequency bands, because the operating band is wider and the communication capacity is larger only by increasing the transmission frequency. As such communication demands increase, development of related communication systems has been necessary. At present, such communication systems have already been on the market with a certain market share, and the development of high-capacity, high-rate data transmission in the future is inevitable in the near future.

However, as the operating frequency of the communication system is increased, the development of the related electronic components becomes more difficult, and the technical and process requirements are higher, especially in the millimeter wave frequency band, and the output power of the transmitter needs to be increased for the communication distance of the signal transmitted by the transmitter in the frequency band to be longer. For millimeter waves, a small increase in transmission power may be realized at a high cost. Therefore, increasing the transmission power in this manner is disadvantageous to the market popularity of millimeter wave communication, which requires that technical breakthroughs must be found from other aspects to make up for the deficiencies of this manner.

Throughout most millimeter wave communication systems, the implementation schemes are basically uniform, and one of the points is that there is a basic device in these systems, namely a waveguide duplex filter, which is a passive power-loss device, and especially in millimeter wave communication, the performance of the millimeter wave communication system is located at the transceiving front end of the system, and the performance of the millimeter wave communication system directly affects the performance of the whole communication system. However, in the current common communication equipment, the index of the waveguide duplex filter still needs to be further improved, and especially the reduction of the insertion loss directly affects the output power of the transmitter, which is the change of the index, and has important significance for improving the performance of the system.

Disclosure of Invention

The invention aims to realize a TE103 waveguide mode-based duplex filter, provides a duplex filter which has the outstanding advantages of simple structure, low processing complexity, small influence of assembly errors on technical indexes and the like aiming at the high requirements of the conventional microwave millimeter wave communication system, and simultaneously solves the contradiction requirement of in-band insertion loss and out-of-band high attenuation. Due to the simple structure, the reliability of the device is improved, the related higher requirements of the microwave millimeter wave communication system can be effectively met, and the device has wide application prospect in the microwave millimeter wave communication system.

The invention relates to a duplex filter based on a TE103 waveguide mode, which comprises a main cavity body 1 and a cover plate 20, wherein the cover plate covers the main cavity body to form a waveguide cavity body. A common waveguide port 18 is formed in the center of the cover plate; the central position of the main cavity is provided with a step 2, and the step 2 is positioned at the projection position of the common waveguide port 18 on the main cavity;

the main cavity is divided into a high-frequency cavity and a low-frequency cavity; the high-frequency cavity and the low-frequency cavity are distributed in two sides relative to a straight line l 1; the high-frequency cavity and the low-frequency cavity are coupled through a common coupling window, the step 2 is arranged in the common coupling window, the central line of the common coupling window is a straight line l1, and the projection of the central line l2 in the length direction of the step 2 in the common coupling window is superposed with a straight line l 1;

for a high frequency cavity:

from left to right, a high-frequency band waveguide port 9, a high-frequency TE103 mode cross coupling window 7, a high-frequency TE103 mode coupling window 8 and a high-frequency TE103 mode resonant cavity 6 are arranged in sequence;

the cavity structure of the high-frequency cavity is as follows: the two U-shaped cavities are arranged in parallel at the left and right, and the linear cavity is arranged above the two U-shaped cavities;

the left side of the left U-shaped cavity is coupled with the high-frequency band waveguide port 9; the left side of the linear cavity is coupled to the left side of the left U-shaped cavity through a coupling hole, and the coupling hole is a cross coupling window 7 of the TE103 mode; the right side of the linear cavity is coupled to the right side of the left U-shaped cavity through a coupling hole, and the coupling hole is a high-frequency TE103 mode coupling window 8;

the connecting edges of the left U-shaped cavity and the right U-shaped cavity extend into the I-shaped cavity, a coupling hole is formed between the connecting edges and the top edge of the I-shaped cavity, and the cavity between the coupling hole and the right edge of the I-shaped cavity is the high-frequency TE103 mode resonant cavity 6;

the right side of the right U-shaped cavity is coupled to the public coupling window, and the right side of the straight cavity is coupled to the right side of the right U-shaped cavity through the coupling hole;

tuning threaded holes penetrating through the main cavity are formed in the side surfaces of the linear cavity, the U-shaped cavities and the coupling holes;

for low frequency cavities:

from right to left are a low-band waveguide port 10, a low-frequency TE103 mode cross-coupling window 5, a low-frequency TE103 mode coupling window 4, and a low-frequency TE103 mode resonator 3 in this order.

Further, the common waveguide port 18 is a standard BJ320 waveguide port; the high-band waveguide port 9 is a BJ320 high-band waveguide port; the low band waveguide port 10 is a BJ320 low band waveguide port.

Further, the common waveguide port 18 is a common waveguide T-junction.

The invention utilizes the characteristic that the high Q value of the resonant cavity of the waveguide TE103 mode can generate good pass band insertion loss in the waveguide filter, and simultaneously adds the cross coupling structure of the resonant cavity to improve the pass band isolation of high and low ends. In the aspect of structure, due to the fact that machining is convenient, the influence of assembly on performance indexes can be almost ignored, technical indexes are excellent, and the like, the method is also a prominent advantage of the method.

Drawings

Fig. 1 is a bottom view of a main cavity portion of the duplex filter of the present embodiment;

fig. 2 is a front view of a main cavity portion of the duplex filter of the present embodiment;

fig. 3 is a top plan view of the main cavity portion of the duplex filter of the present embodiment;

fig. 4 is a bottom view of the duplex filter cover plate portion of the present embodiment;

fig. 5 is a front view of the duplex filter cover plate portion of the present embodiment;

fig. 6 is a top view of the duplex filter cover plate portion of the present embodiment;

fig. 7 is a schematic external view of the duplex filter of the present embodiment;

in the figure: a main cavity (1), a step (2) at the center of a waveguide T-shaped joint, a low-frequency TE103 mode resonant cavity (3), a low-frequency TE103 mode coupling window (4), a low-frequency TE103 mode cross coupling window (5), a high-frequency TE103 mode resonant cavity (6), a high-frequency TE103 mode cross coupling window (7), a high-frequency TE103 mode coupling window (8), a BJ320 high-frequency band waveguide port (9) and a BJ320 low-frequency band waveguide port (10), the high-frequency resonance tuning structure comprises a high-frequency resonance tuning threaded hole (11), a high-frequency coupling tuning threaded hole (12), a low-frequency coupling tuning threaded hole (13), a low-frequency resonance tuning threaded hole (14), a fixing hole (15) of a main cavity, an installation hole (16), an installation hole (17) of a public port, a public waveguide port (waveguide T-shaped joint) (18), a fastening hole (19) of a cover plate and a cover plate (20).

Detailed Description

The invention provides a duplex filter based on a TE103 waveguide mode, and belongs to the field of microwave and millimeter wave communication. The method mainly utilizes the characteristics of the TE103 waveguide mode to solve the problem that the single-cavity resonance Q value of the conventional waveguide duplex filter is relatively small, and brings the results of low loss and high out-of-band attenuation.

The invention is further described with reference to the following detailed description of embodiments in conjunction with the accompanying drawings:

a duplex filter based on TE103 waveguide mode comprises a main cavity 1 and a cover plate 20, wherein the cover plate covers the main cavity to form a waveguide cavity. A common waveguide port 18 is formed in the center of the cover plate; the central position of the main cavity is provided with a step 2, and the step 2 is positioned at the projection position of the common waveguide port 18 on the main cavity;

the main cavity is divided into a high-frequency cavity and a low-frequency cavity; the high frequency cavity and the low frequency cavity are in a two-sided structure about a straight line l 1; the high-frequency cavity and the low-frequency cavity are coupled through a common coupling window, the step 2 is arranged in the common coupling window, the central line of the common coupling window is a straight line l1, and the projection of the central line l2 in the length direction of the step 2 in the common coupling window is superposed with a straight line l 1;

for a high frequency cavity:

from left to right, a high-frequency band waveguide port 9, a high-frequency TE103 mode cross coupling window 7, a high-frequency TE103 mode coupling window 8 and a high-frequency TE103 mode resonant cavity 6 are arranged in sequence;

the cavity structure of the high-frequency cavity is as follows: the two U-shaped cavities are arranged in parallel at the left and right, and the linear cavity is arranged above the two U-shaped cavities;

the left side of the left U-shaped cavity is coupled with the high-frequency band waveguide port 9; the left side of the linear cavity is coupled to the left side of the left U-shaped cavity through a coupling hole, and the coupling hole is a cross coupling window 7 of the TE103 mode; the right side of the linear cavity is coupled to the right side of the left U-shaped cavity through a coupling hole, and the coupling hole is a high-frequency TE103 mode coupling window 8;

the connecting edges of the left U-shaped cavity and the right U-shaped cavity extend into the I-shaped cavity, a coupling hole is formed between the connecting edges and the top edge of the I-shaped cavity, and the cavity between the coupling hole and the right edge of the I-shaped cavity is the high-frequency TE103 mode resonant cavity 6;

the right side of the right U-shaped cavity is coupled to the public coupling window, and the right side of the straight cavity is coupled to the right side of the right U-shaped cavity through the coupling hole;

tuning threaded holes penetrating through the main cavity are formed in the side surfaces of the linear cavity, the U-shaped cavities and the coupling holes;

for low frequency cavities:

from right to left are a low-band waveguide port 10, a low-frequency TE103 mode cross-coupling window 5, a low-frequency TE103 mode coupling window 4, and a low-frequency TE103 mode resonator 3 in this order.

Further, the common waveguide port 18 is a standard BJ320 waveguide port; the high-band waveguide port 9 is a BJ320 high-band waveguide port; the low band waveguide port 10 is a BJ320 low band waveguide port.

Further, the common waveguide port 18 is a common waveguide T-junction.

The principle of the duplex filter based on the TE103 waveguide mode in the embodiment is that the duplex filter comprises a common standard BJ320 waveguide port 18, a standard BJ320 high-frequency band waveguide port 9, a standard BJ320 low-frequency band waveguide port 10, high and low end TE103 mode resonant cavities 3 and 6, high and low end TE103 mode coupling windows 4 and 8, high and low frequency TE103 mode cross coupling windows 5 and 7, a common waveguide T-shaped joint 18, a main cavity cover plate 20, tuning threaded holes 11, 12, 13 and 14 and the like.

The high-frequency and low-frequency TE103 mode resonant cavity is the core part of the duplex filter of the waveguide mode, and is also the key part of the high Q value of the single cavity of the duplex filter of the TE103 waveguide mode, and directly determines the pass-band insertion loss of the duplex filter of the TE103 waveguide mode. According to the related theory, the definition of the Q value of a single cavity is the ratio of the energy storage to the energy consumption of the cavity. Because the TE103 mode of the waveguide is utilized, the volume of the resonant cavities 3 and 6 is 3 times of that of a conventional single cavity theoretically, and thus the energy storage capacity of the cavity is approximately 3 times of that of the conventional cavity, so that the energy storage capacity of the TE103 mode is quite large, and the energy consumption difference between the TE103 mode and the conventional mode is very small. Therefore, the insertion loss of the waveguide filter designed in TE103 mode can be greatly reduced. Due to the duplex filter, the high and low ends are at different frequencies, with a slight difference in frequency, and thus the sizes of the resonant cavities at the high and low ends are different to ensure that the respective resonant frequencies are within the desired range. The TE103 modes discussed above are for the respective resonators.

Besides the important resonant cavity of the TE103 mode, the duplex filter based on the TE103 waveguide mode has another structural form which has a larger influence on the isolation of high and low end channels, namely a cross coupling window 5 and 7 structure. From the basic knowledge of the filter, it can be known that, in general, the more resonators 3 and 6 of the filter, the greater the attenuation outside the band, but this is a contradictory matter with the insertion loss inside the band, and the more resonators and the greater the insertion loss inside the band, so the use of TE103 mode can compensate this deficiency. To improve the out-of-band attenuation, a very efficient approach is adopted for the cell cross-coupling window 5, 7 structure.

The duplex filter of the TE103 waveguide mode mainly utilizes the phase and amplitude relation of a certain out-of-band frequency after the cross coupling windowing of the separate cells, and if the out-of-band attenuation is possibly large due to the ideal offset effect, the phase difference of 180 degrees and the same amplitude are required to be met. For a duplex filter based on a TE103 waveguide mode, the main out-of-band attenuation is the mutual isolation of a high-end frequency and a low-end frequency, and cross coupling is generated to perform respective attenuation on the high-end frequency and the low-end frequency, so that the attenuation of the cross coupling has relative high and low side frequencies, for the high-end passband of the duplex filter based on the TE103 waveguide mode, the low-end passband frequency needs to be attenuated, and a capacitive cross coupling form is arranged in cross coupling window structures 5 and 7; for the low-end pass band of the duplex filter of the TE103 waveguide mode, it is the high-end pass band frequency that needs to be attenuated, and an inductive cross-coupling form is set in the cross-coupling. The methods are equivalent to additionally introducing out-of-band attenuation except for the out-of-band attenuation of the filter formed by the TE103 mode resonant cavities 3 and 6, so that the passband isolation of the duplex filter of the TE103 waveguide mode is increased without remarkably increasing the in-band insertion loss.

The above mainly describes the TE103 mode resonant cavities 3, 6, the cell cross coupling windows 5, 7 structures, etc. in the main constitution of the duplex filter based on the TE103 waveguide mode of the present invention, in addition to which there is a waveguide T-type connector 18, the function of this connector is to connect the filters of high and low ends into a duplexer with required characteristics, which is one of the key parts for realizing the duplexer, and the structure of this part is designed as a key part for optimizing the duplexer index. The basic working principle is that the common end can input and output signals in high and low end frequency ranges, and the two branch channels respectively correspond to the frequency passband of the high-end filter and the frequency passband of the low-end filter. The waveguide T-shaped joint 18 is provided with a concave step 2 at the center, and the step 2 has the following functions: the method comprises the steps of matching a public port, eliminating the influence of a waveguide high-order mode, and effectively distributing the frequency pass bands of high and low ends. The high and low ends of the waveguide T-junction 18 typically have a section of standard waveguide corresponding to the high and low end filters of the TE103 waveguide mode, respectively, thus forming an integral duplex filter.

The invention carries out integrated structure design on the resonant cavities 3 and 6, the coupling windows 4 and 8, the cross coupling windows 5 and 7, the tuning threaded holes 11, 12, 13 and 14 and the like of the step 2 and the TE103 mode, carries out other integrated structure design on the public port and the resonant cavity cover plate of the TE103 mode, welds the two parts through high-temperature solder after silvering, and simultaneously installs screws through the fixing hole 15 of the main cavity, the fastening hole 19 of the cover plate and the installation hole 16, thus forming the complete TE103 mode waveguide duplex filter. Because the whole TE103 mode waveguide duplex filter mainly comprises the main cavity 1 and the cover plate 20, and the installation of the cover plate 20 has almost no influence on the indexes of the device, the assembly difficulty can be effectively reduced, the success rate of the product is improved, and great convenience is brought to the production work. The design idea is characterized in that the problems of relatively simple processing and small influence of assembly on technical index results are solved, and meanwhile, the reliability of the TE103 mode waveguide duplex filter is improved due to the simple assembly. Has wide market prospect in various microwave and millimeter wave communication electronic devices.

The invention is mainly characterized in that the characteristic that the high Q value of the resonant cavity of the waveguide TE103 mode can generate good pass band insertion loss when applied to a waveguide filter is utilized, and meanwhile, the cross coupling structure of the resonant cavity is added to improve the pass band isolation of high and low ends. In the aspect of structure, due to the fact that machining is convenient, the influence of assembly on performance indexes can be almost ignored, technical indexes are excellent, and the like, the method is also a prominent advantage of the method.

The technical index of the duplex filter based on the TE103 waveguide mode, designed by the requirements of the system, is as follows:

(1) and the working frequency: ka wave band

(2) And working bandwidth: 300MHz

(3) Insertion loss: not more than 0.8dB

(4) Port standing waves: less than or equal to 1.2

(5) And isolation of transmitting and receiving: not less than 80dB

(6) And interface form: BJ320 standard waveguide

(7) And working temperature: minus 40 ℃ to plus 55 DEG C

(8) And storage temperature: -55 ℃ to +70 ℃.