Coaxial resonant cavity duplexer for indoor distribution system

Abstract

The invention provides a coaxial resonant cavity duplexer for an indoor distribution system. The coaxial resonant cavity duplexer comprises a first waveguide cavity, a second waveguide cavity and a third waveguide cavity, wherein a first resonant metal module is arranged in the first waveguide cavity, a second resonant metal module is arranged in the second waveguide cavity, and a third resonant metal module is arranged in the third waveguide cavity; the first resonant metal module comprises a first resonant metal unit and a second resonant metal unit, the first resonant metal unit and the second resonant metal module resonate to form a first passband, and the second resonant metal unit and the third resonant metal module resonate to form a second passband; the first surface of the first waveguide cavity is further provided with a common signal transmission port, the first surface of the second waveguide cavity is provided with a first signal output port, the first surface of the third waveguide cavity is provided with a second signal output port, and efficient frequency separation and mode coupling are achieved through the optimized waveguide cavities and the optimized resonant metal module. Meanwhile, the size and the weight are effectively reduced.

Description

Technical Field

[0001] The present application relates to the field of microwave technology, and in particular to a coaxial resonant cavity duplexer for a room-distributed system. Background Art

[0002] With the rapid development of wireless communication technology, new requirements for high performance, miniaturization, low cost and easy integration have been put forward for microwave passive devices. To meet these standards, duplexers have emerged. By integrating two channel filters and sharing one input port and one antenna, it simplifies the RF front-end system architecture, realizes orderly transmission of signals, reduces equipment cost and volume, and avoids mutual interference between receiving and transmitting signals.

[0003] Currently, the design of duplexers mainly adopts a traditional structure and uses two independent bandpass filters and a coupling junction, or eliminates the coupling junction and uses two independent filters.

[0004] However, the duplexer using the bandpass filter occupies a large size and cannot meet the lightweight structural requirements of the duplexer. Summary of the invention

[0005] The present application provides a coaxial resonant cavity duplexer for a room-distributed system, so as to solve the problem that the existing duplexer is insufficient in miniaturization and lightness.

[0006] The present application provides a coaxial resonant cavity duplexer for a room-divided system, comprising:

[0007] a first waveguide cavity, a second waveguide cavity, and a third waveguide cavity;

[0008] Wherein, a first resonant metal module is arranged in the first waveguide cavity, a second resonant metal module is arranged in the second waveguide cavity, and a third resonant metal module is arranged in the third waveguide cavity;

[0009] The first resonant metal module includes a first resonant metal unit and a second resonant metal unit, the first resonant metal unit resonates with the second resonant metal module to form a first passband, and the second resonant metal unit resonates with the third resonant metal module to form a second passband;

[0010] A common signal transmission port is also arranged on the first surface of the first waveguide cavity, a first signal output port is arranged on the first surface of the second waveguide cavity, and a second signal output port is arranged on the first surface of the third waveguide cavity.

[0011] Optionally, the common signal transmission port is a common signal port of the first waveguide cavity, the second waveguide cavity and the third waveguide cavity in the coaxial resonant cavity duplexer;

[0012] The first signal output port is a signal output port of the second waveguide cavity;

[0013] The second signal output port is a signal output port of the third waveguide cavity.

[0014] Optionally, the second resonant metal unit is sleeved on the first resonant metal unit.

[0015] Optionally, the second surface of the first waveguide cavity is coupled to the second surface of the second waveguide cavity through a first coupling window;

[0016] The third surface of the first waveguide cavity is coupled to the second surface of the third waveguide cavity through the second coupling window;

[0017] The second side of the first waveguide cavity is opposite to the third side of the first waveguide cavity.

[0018] Optionally, the first coupling window and the second coupling window are both rectangular, and the first coupling window and the second coupling window have different sizes.

[0019] Optionally, the common signal transmission port, the first signal output port and the second signal output port are all provided with SMA connector feeding probes;

[0020] The lengths of the feeding probes of the various SMA connectors are different.

[0021] Optionally, a third resonant metal unit is provided in the second resonant metal module;

[0022] The third resonant metal module is provided with a fourth resonant metal unit.

[0023] Optionally, an L-shaped coupling probe is arranged in the second coupling window.

[0024] Optionally, the L-shaped coupling probe comprises two metal cylinders;

[0025] Two metal cylinders are connected vertically.

[0026] Optionally, the distance between the first signal output port and the bottom surface of the coaxial resonant cavity duplexer is shorter than the distance between the common signal transmission port and the bottom surface of the coaxial resonant cavity duplexer;

[0027] The distance between the common signal transmission port and the bottom surface of the coaxial resonant cavity duplexer is shorter than the distance between the second signal output port and the bottom surface of the coaxial resonant cavity duplexer.

[0028] The present application provides a coaxial resonant cavity duplexer for a room-distributed system, comprising a first waveguide cavity, a second waveguide cavity and a third waveguide cavity; wherein a first resonant metal module is arranged in the first waveguide cavity, a second resonant metal module is arranged in the second waveguide cavity, and a third resonant metal module is arranged in the third waveguide cavity; the first resonant metal module comprises a first resonant metal unit and a second resonant metal unit, the first resonant metal unit resonates with the second resonant metal module to form a first passband, and the second resonant metal unit resonates with the third resonant metal module to form a second passband; a common signal transmission port is also arranged on the first surface of the first waveguide cavity, a first signal output port is arranged on the first surface of the second waveguide cavity, and a second signal output port is arranged on the first surface of the third waveguide cavity, and efficient frequency separation and mode coupling are achieved through precisely optimized waveguide cavities and resonant metal modules, while effectively reducing volume and weight. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0030] Figure 1 A schematic diagram of the structure of a first embodiment of a coaxial resonant cavity duplexer for a room-divided system provided by the present application;

[0031] Figure 2 A schematic diagram of the structure of the second embodiment of the coaxial resonant cavity duplexer for indoor distributed systems provided by the present application;

[0032] Figure 3 A schematic diagram of the structure of the third embodiment of the coaxial resonant cavity duplexer for indoor distributed systems provided by the present application;

[0033] Figure 4 The topology diagram of the coaxial resonant cavity duplexer for the room distribution system provided by this application;

[0034] Figure 5 A graph showing the frequency variation of the coaxial resonant cavity duplexer for the room distribution system provided by the present application with respect to the size r2;

[0035] Figure 6 The simulation and test diagram of the filtering characteristics of the coaxial resonant cavity duplexer for the indoor distributed system provided by this application;

[0036] Figure 7 Isolation parameter simulation and test diagram of the coaxial resonant cavity duplexer for the indoor distributed system provided in this application.

[0037] Reference numerals:

[0038] 100-coaxial resonant cavity duplexer for indoor distributed system; 101-first waveguide cavity; 102-second waveguide cavity; 103-third waveguide cavity; 201-first resonant metal unit; 202-second resonant metal unit; 203-third resonant metal unit; 204-fourth resonant metal unit; 301-common signal transmission port; 302-first signal output port; 303-second signal output port; 401-first coupling window; 402-second coupling window.

[0039] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0040] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0041] The existing duplexers are complex in design, large in size and heavy in weight, making it difficult to meet the requirements of lightweight and miniaturized equipment in indoor distributed systems. At the same time, the existing duplexers have low signal coupling efficiency between waveguide cavities, inaccurate mode matching, and high signal transmission loss and interference, which results in the inability to fully utilize system performance and limits their application in high-frequency communication scenarios.

[0042] To address the above problems, this solution achieves efficient signal coupling and low-loss transmission in terms of structure and material by designing a rectangular coupling window, an L-shaped coupling probe and an optimized SMA feeding probe. At the same time, through a compact nested structure and modular design, the volume and weight of the duplexer are greatly reduced, providing a new technical path for efficient and miniaturized duplexers in indoor distributed systems.

[0043] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0044] Figure 1 This is a schematic diagram of the structure of the first embodiment of the coaxial resonant cavity duplexer for the room-divided system provided by the present application. Figure 1As shown, the coaxial resonant cavity duplexer 100 for the room distribution system includes:

[0045] A first waveguide cavity 101 , a second waveguide cavity 102 and a third waveguide cavity 103 .

[0046] The first waveguide cavity 101 may be a rectangular metal cavity made of a light metal material to reduce the weight of the entire duplexer. A first resonant metal module is provided in the first waveguide cavity 101, and the first resonant metal module includes a first resonant metal unit 201 and a second resonant metal unit 202. The second resonant metal unit 202 is sleeved on the first resonant metal unit 201 and is closely combined together by mutual nesting, so that the first resonant metal unit 201 and the second resonant metal unit 202 form an effective electromagnetic coupling, and at the same time, it can also reduce redundant space, improve the space utilization of the duplexer, and thus reduce the overall volume of the duplexer.

[0047] In addition, the first resonant metal unit 201 and the second resonant metal unit 202 jointly generate two different modes TEM1 and TEM2 in the first waveguide cavity 101. This structure enables the duplexer to achieve efficient mode separation and signal transmission while avoiding the disadvantages of the traditional design that requires multiple large metal parts or complex circuits, thereby greatly reducing the size and weight of the device.

[0048] On the other hand, a second resonant metal module is provided in the second waveguide cavity 102. The second waveguide cavity 102 is a cylindrical metal cavity. The cylindrical design can effectively utilize space, reduce unnecessary structural volume, and improve the transmission efficiency of electromagnetic waves through optimized design.

[0049] A second resonant metal module is disposed at the center of the second waveguide cavity 102, and a third resonant metal unit 203 is disposed in the second resonant metal module. The third resonant metal unit 203 is designed to generate a single-mode Mode 1 in the second waveguide cavity 102. Since the wavelength and resonant frequency of the electromagnetic wave of Mode 1 are precisely matched, the space requirement can be minimized and good signal quality can be maintained.

[0050] Secondly, the third waveguide cavity 103 is also a cylindrical metal cavity, and its size and shape are the same as those of the second waveguide cavity 102. Through the reasonably designed size and proportion, the waveguide cavity can effectively carry the required electromagnetic waves and reduce unnecessary space waste. A third resonant metal module is arranged at the center of the third waveguide cavity 103, and a fourth resonant metal unit 204 is arranged in the third resonant metal module for generating single-mode Mode2.

[0051] In the coaxial resonant cavity duplexer for the room-divided system proposed in the present application, a common signal transmission port 301 is also provided on the first surface of the first waveguide cavity 101, and the common signal transmission port 301 can be used as a signal input port for the first waveguide cavity 101, the second waveguide cavity 102 and the third waveguide cavity 103. The common signal transmission port 301, as the core signal input port of the coaxial resonant cavity duplexer, can support signal coupling and transmission between different waveguide cavities, so that the duplexer can process multiple signal frequency bands. By optimizing the position and design of the common signal transmission port 301, signal loss and intermodulation interference can be significantly reduced, thereby improving the performance of the duplexer in high-frequency transmission.

[0052] Secondly, a first signal output port 302 is also provided on the first surface of the second waveguide cavity 102, serving as a signal output port of the second waveguide cavity 102, for transmitting the Mode 1 signal generated by the second waveguide cavity 102 and outputting it outside the duplexer, thereby ensuring the stability and effectiveness of signal transmission and having low reflection loss.

[0053] A second signal output port 303 is provided on the first surface of the third waveguide cavity 103, serving as a signal output port of the third waveguide cavity, for transmitting the Mode 2 signal generated by the third waveguide cavity 103, and transmitting it to an external device through the port, thereby avoiding mutual interference between signals, so that the duplexer can achieve accurate frequency separation and signal processing.

[0054] Furthermore, the common signal transmission port 301, the first signal output port 302 and the second signal output port 303 are all provided with SMA connector feeding probes; the SMA connector is a standard RF connection method, commonly used for high-frequency signal transmission, and has good signal stability and low insertion loss characteristics.

[0055] Among them, the lengths of the various SMA connector feeding probes are different. The length of the SMA connector feeding probe of the common signal transmission port 301 is adjusted according to the design of the first waveguide cavity 101 to ensure stable transmission and proper matching of the signal. The lengths of the SMA connector feeding probes of the first signal output port 302 and the second signal output port 303 are also adjusted according to the operating frequency of each waveguide cavity and the propagation characteristics of the electromagnetic wave. By adjusting the lengths of these probes, the output power and bandwidth of the signal can be accurately controlled while reducing unnecessary signal loss.

[0056] Through the differentiated design of the SMA connector feeding probe length, the signal transmission path is further optimized, so that the entire coaxial resonant cavity duplexer can efficiently transmit signals under high-frequency working conditions, while avoiding signal interference, distortion and attenuation problems, ensuring the stable operation of the coaxial resonant cavity duplexer in complex room distribution systems.

[0057] Furthermore, the coaxial resonant cavity duplexer for the room-divided system provided in the embodiment of the present application realizes efficient coupling of electromagnetic signals between the first waveguide cavity 101 and the second waveguide cavity 102 and the third waveguide cavity 103 by setting a first coupling window 401, a second coupling window 402 and an L-shaped probe, so as to further improve the performance of the coaxial resonant cavity duplexer.

[0058] Specifically, the second surface of the first waveguide cavity 101 is coupled to the second surface of the second waveguide cavity 102 through the first coupling window 401. The first coupling window 401 is rectangular in design, and its size can be adjusted according to the actual application scenario to match the coupling requirements between the TEM1 generated by the first waveguide cavity and the single mode Mode1 generated by the second waveguide cavity 102, so that the transmission efficiency of the signal between the first waveguide cavity 101 and the second waveguide cavity 102 is maximized, while reducing the reflection loss and improving the overall performance.

[0059] The third surface of the first waveguide cavity 101 is coupled to the second surface of the third waveguide cavity 103 through the second coupling window 402, so as to realize signal coupling between the first waveguide cavity 101 and the third waveguide cavity 103. The second coupling window 402 is also designed in a rectangular shape, and its size is different from that of the first coupling window 401, so as to adapt to the coupling characteristics of the single mode Mode2 generated by the third waveguide cavity 103 and the TEM2 mode of the first waveguide cavity 101. By adjusting the size ratio, the effective transmission of signal energy is ensured, while reducing mode interference.

[0060] It should be noted that the second surface of the first waveguide cavity 101 and the third surface of the first waveguide cavity 101 are arranged opposite to each other, forming a good structural symmetry, which is helpful to evenly distribute the electromagnetic field and further improve the signal transmission stability.

[0061] In addition, an L-shaped coupling probe is provided in the second coupling window 402, which is used to achieve more efficient signal coupling between the first waveguide cavity 101 and the third waveguide cavity 103. Specifically, the L-shaped coupling probe includes two metal cylinders, which are vertically connected to form an L-shaped structure. Among them, the first cylinder (metal arm) is arranged horizontally for coupling with the electric field in the first waveguide cavity 101, and the second cylinder (metal leg) is arranged vertically for coupling with the electric field in the third waveguide cavity 103. It should be noted that the L-shaped coupling probe uses a highly conductive metal material to ensure efficient transmission and low loss of electromagnetic signals.

[0062] The coaxial resonant cavity duplexer for the room-divided system provided in the embodiment of the present application realizes high efficiency and flexibility of signal transmission by designing multiple waveguide cavities, a common signal transmission port 301 and multiple signal output ports, and a targeted adjustment of the SMA connector feeding probe. The stability, accuracy and bandwidth utilization of the signal are improved, and by optimizing the structure and streamlining the components, the coaxial resonant cavity duplexer achieves the goal of miniaturization and lightness, and is particularly suitable for application environments with strict requirements on space and weight in modern room-divided systems.

[0063] Figure 2 This is a schematic diagram of the structure of the second embodiment of the coaxial resonant cavity duplexer for indoor distributed systems provided by this application. Figure 2 As shown, in Figure 1 Based on the embodiment, a top view of a coaxial resonant duplexer for a room distribution system is shown, wherein information of various parameters includes:

[0064] r1 represents the radius of the first resonant metal unit 201, which determines the layout position of the metal unit in the first waveguide cavity 101. The setting of its size affects the adjustment of the resonant frequency and the coupling relationship with other cavities. The second resonant metal unit 202 is a hollow metal cylinder, and r2 represents the hollow radius of the metal cylinder where the second resonant metal unit 202 is located, and r3 represents the radius of the second resonant metal unit 202 itself. r4 represents the radius of the fourth resonant metal unit 204, r5 represents the hollow radius of the metal cylinder where the third resonant metal unit 203 is located, and r6 represents the radius of the third resonant metal unit 203 itself.

[0065] For example, if r1 is too large, the metal unit will deviate from the expected position, thereby affecting the resonant mode of the entire duplexer, while if it is too small, it may cause poor coupling or impedance mismatch. Therefore, a reasonable setting of r1 helps to improve the efficiency and stability of the coaxial resonant cavity duplexer.

[0066] w_w1 represents the width of the first coupling window 401, thereby affecting the coupling strength of the signal. A larger coupling window width can improve the coupling efficiency, but too large a width may introduce unnecessary signal interference or affect system stability.

[0067] w_w2 represents the width of the second coupling window 402. Adjusting the size of w_w2 is helpful to control the coupling strength between the third resonant cavity and other parts, and optimize the frequency response and signal isolation.

[0068] w_t1 represents the thickness of the first coupling window 401 between the first waveguide cavity 101 and the second waveguide cavity 102. w_t1 controls the coupling area between the first waveguide cavity 101 and the second waveguide cavity 102. The size of this parameter determines the coupling strength between the waveguides, which in turn affects the working bandwidth and signal transmission efficiency of the duplexer. An appropriate w_t1 can ensure good coupling between the waveguides while avoiding signal loss caused by excessive coupling.

[0069] w_t2 represents the thickness of the second coupling window 402 between the first waveguide cavity 101 and the third waveguide cavity 103. Similar to w_t1, w_t2 controls the coupling between the first waveguide cavity 101 and the third waveguide cavity 103. Adjustment of this parameter also affects the signal isolation effect and the performance of the duplexer in different frequency bands. Reasonable w_t2 settings can help optimize the operating frequency response of the duplexer and ensure that signals can be effectively separated between different channels.

[0070] For example, the parameters of each part of the coaxial resonant cavity duplexer for the room distributed system proposed in the application embodiment may be r1=2.3, r2=8.3, r3=9.8, r4=2.2, r5=3.3, r6=5.4, w_w1=17, w_w2=10, w_t1=2.4, w_t2=2.4, where the unit of each parameter is mm.

[0071] The coaxial resonant cavity duplexer for the room-divided system provided in the embodiment of the present application has various parameters set to ensure its working efficiency and signal separation capability in the room-divided system. By reasonably adjusting the values ​​of various parameters, the resonant frequency, bandwidth, coupling strength and signal isolation effect can be controlled, thereby improving the overall performance of the duplexer and enabling it to work stably in a multi-band system.

[0072] Figure 3 This is a schematic diagram of the structure of the third embodiment of the coaxial resonant cavity duplexer for the room-divided system provided by this application. Figure 3 As shown, in Figure 1 Based on the embodiment, the main view of the coaxial resonant duplexer for the indoor distributed system is shown. The information of each parameter includes:

[0073] H1 represents the height of the first resonant metal unit 201. The H1 parameter determines the vertical size (height) of the first resonant cavity. The change in height will directly affect the resonant frequency and the volume of the cavity. The reasonable setting of H1 can ensure that the first resonant cavity can work effectively within the predetermined frequency band and maintain a good coupling relationship with other resonant cavities.

[0074] H2 represents the height of the second resonance unit. By adjusting H2, the resonance frequency of the second resonance unit can be matched with the design requirements of the coaxial resonant cavity duplexer, thereby optimizing the signal isolation and frequency response of the duplexer.

[0075] H3 represents the height of the third resonant unit, and H4 represents the height of the fourth resonant unit. It is usually used to adjust the heights of the third resonant unit and the fourth resonant unit, and can adjust the bandwidth and signal isolation capability of the entire coaxial resonant cavity duplexer.

[0076] h1 represents the distance from the center of the common signal port to the bottom surface, h2 represents the distance from the center of the first signal output port 302 to the bottom surface, and h3 represents the distance from the center of the second signal output port 303 to the bottom surface. The adjustment of each height can affect the matching and signal transmission quality of the port. Appropriate settings of h1, h2, and h3 can ensure that the coupling effect between the signal port and the resonant cavity is maximized and avoid unnecessary signal loss or reflection.

[0077] Among them, the distance between the first signal output port 302 and the bottom surface of the coaxial resonant cavity duplexer is shorter than the distance between the common signal transmission port 301 and the bottom surface of the coaxial resonant cavity duplexer; the distance between the common signal transmission port 301 and the bottom surface of the coaxial resonant cavity duplexer is shorter than the distance between the second signal output port 303 and the bottom surface of the coaxial resonant cavity duplexer.

[0078] Cl1 represents the length of the first metal cylinder of the L-type coupling probe, and Cl2 represents the length of the second metal cylinder of the L-type coupling probe. Adjustment of Cl1 and Cl2 affects the coupling strength between the first waveguide cavity 101 and the third waveguide cavity 103, thereby affecting the performance of the coaxial resonant cavity duplexer.

[0079] Exemplarily, in the embodiment of the present application, the above parameters can be set to H1=23, H2=25, H3=25.5, H4=18, h1=10.2, h2=6, h3=23, wherein the unit of each parameter is mm.

[0080] The parameter settings provided in the embodiments of the present application are crucial for the design of coaxial resonant duplexers for indoor distributed systems. They not only affect the physical size of the duplexer, but also determine the performance of the coaxial resonant duplexer in different frequency bands, including signal transmission, isolation and coupling efficiency. By precisely controlling these parameters, designers can optimize the overall performance of the duplexer and ensure that it can work stably and efficiently in a complex wireless communication environment.

[0081] Figure 4 The topology diagram of the coaxial resonant cavity duplexer for the room distribution system provided by this application. The topology uses the cascade of dual-mode cavity and single-mode cavity to construct a coaxial resonant cavity duplexer, which is widely used in many wireless communication and radio frequency devices.

[0082] The dual-mode cavity is used to support signal transmission in two different frequency bands, while the single-mode cavity plays the role of filtering and separation. Through this cascade design, frequency separation can be achieved to ensure that signals in each frequency band can be transmitted without interfering with each other. In addition, by adopting this optimized topology, the design can significantly reduce the volume while maintaining performance, making the duplexer suitable for installation in space-constrained application scenarios, such as indoor distributed systems or miniaturized communication equipment.

[0083] Figure 5 The frequency of the coaxial resonant cavity duplexer for the room distribution system provided by this application varies with the size r2. Figure 5 As shown, the two mode frequency curves of the resonator of the coaxial resonant cavity duplexer under the simulation of high-frequency electromagnetic simulation software (English: High Frequency Structure Simulator, referred to as: HFSS) are shown as the r2 changes, as well as the change of the frequency ratio of the two modes.

[0084] By adjusting r2, the frequencies of the two different channels can be adjusted so that the duplexer can operate within a specific frequency range. As the r2 parameter changes, the operating frequencies of the two channels also change. As shown in the figure, a frequency shift is shown, indicating the fine-tuning effect of r2 on the resonant frequency. By precisely controlling this parameter, the operating performance of the coaxial resonant cavity duplexer can be optimized within the target frequency band.

[0085] Figure 6 Simulation and test diagram of filtering characteristics of the coaxial resonant cavity duplexer for indoor distributed systems provided in this application.

[0086] Among them, return loss is an indicator to measure the degree of signal reflection. Generally, the greater the return loss, the less signal reflection, which means the better the matching performance of the device. In the figure, the return loss of channel 1 and channel 2 are both higher than 20dB, which means that the duplexer can effectively eliminate signal reflection, thereby reducing signal loss and improving communication quality.

[0087] Insertion loss indicates the power loss of a signal when it passes through a duplexer. The insertion loss values ​​in the figure show that the duplexer has very low loss on both channels, indicating that the signal is transmitted more efficiently. This is critical for wireless communication devices, because the lower the insertion loss, the higher the overall efficiency.

[0088] According to the data in the figure, the center frequency of channel 1 is 1.8GHz, the bandwidth is about 6%, and the center frequency of channel 2 is 3.4GHz, the bandwidth is 5.8%. This means that the working bandwidth of the duplexer is wider, which can support more communication signal transmission, thereby increasing the capacity of the system.

[0089] Figure 7 Isolation parameter simulation and test diagram of the coaxial resonant cavity duplexer for the indoor distributed system provided in this application.

[0090] Among them, port isolation means that the signal of one channel will not interfere with the other channel. The data in the figure shows that the isolation between the two channels is greater than 30dB, which means that in actual work, the two channels are almost completely independent and do not interfere with each other. This is a very important performance indicator of the duplexer design, ensuring that the duplexer can transmit signals of two frequency bands at the same time without affecting each other.

[0091] The isolation parameter can be expressed as S, which is an important tool for describing the characteristics of RF devices. 11 The S parameter results in the figure show that the duplexer achieves efficient signal transmission and low loss between the two channels while ensuring good isolation performance.

[0092] Specifically, an isolation higher than 30dB indicates that the duplexer effectively isolates the signals of the two channels, allowing signals of different frequencies to run in parallel in the same system without interfering with each other. This is a very important performance in RF communications, especially in multi-band, multi-channel systems.

[0093] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0094] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A coaxial resonant cavity duplexer for indoor distributed systems, characterized in that: include: a first waveguide cavity, a second waveguide cavity, and a third waveguide cavity; Wherein, a first resonant metal module is arranged in the first waveguide cavity, a second resonant metal module is arranged in the second waveguide cavity, and a third resonant metal module is arranged in the third waveguide cavity; The first resonant metal module includes a first resonant metal unit and a second resonant metal unit, the first resonant metal unit resonates with the second resonant metal module to form a first passband, and the second resonant metal unit resonates with the third resonant metal module to form a second passband; A common signal transmission port is also provided on the first surface of the first waveguide cavity, a first signal output port is provided on the first surface of the second waveguide cavity, and a second signal output port is provided on the first surface of the third waveguide cavity.

2. The coaxial resonant cavity duplexer according to claim 1, characterized in that: The common signal transmission port is a common signal port of the first waveguide cavity, the second waveguide cavity and the third waveguide cavity in the coaxial resonant cavity duplexer; The first signal output port is a signal output port of the second waveguide cavity; The second signal output port is a signal output port of the third waveguide cavity.

3. The coaxial resonant cavity duplexer according to claim 1, characterized in that: The second resonant metal unit is sleeved on the first resonant metal unit.

4. The coaxial resonant cavity duplexer according to any one of claims 1 to 3, characterized in that: The second surface of the first waveguide cavity is coupled to the second surface of the second waveguide cavity through a first coupling window; The third surface of the first waveguide cavity is coupled to the second surface of the third waveguide cavity through a second coupling window; The second surface of the first waveguide cavity is opposite to the third surface of the first waveguide cavity.

5. The coaxial resonant cavity duplexer according to claim 4, characterized in that: The first coupling window and the second coupling window are both rectangular, and the first coupling window and the second coupling window have different sizes.

6. The coaxial resonant cavity duplexer according to any one of claims 1 to 3, characterized in that: The common signal transmission port, the first signal output port and the second signal output port are all provided with SMA connector feeding probes; The lengths of the SMA connector feeding probes are different.

7. The coaxial resonant cavity duplexer according to any one of claims 1 to 3, characterized in that: A third resonant metal unit is provided in the second resonant metal module; The third resonant metal module is provided with a fourth resonant metal unit.

8. The coaxial resonant cavity duplexer according to any one of claims 1 to 3, characterized in that: An L-shaped coupling probe is arranged in the second coupling window.

9. The coaxial resonant cavity duplexer according to claim 8, characterized in that: The L-shaped coupling probe includes two metal cylinders; The two metal cylinders are vertically connected.

10. The coaxial resonant cavity duplexer according to any one of claims 1 to 3, characterized in that: The distance between the first signal output port and the bottom surface of the coaxial resonant cavity duplexer is shorter than the distance between the common signal transmission port and the bottom surface of the coaxial resonant cavity duplexer; The distance between the common signal transmission port and the bottom surface of the coaxial resonant cavity duplexer is shorter than the distance between the second signal output port and the bottom surface of the coaxial resonant cavity duplexer.

Images