Bidirectional low intermodulation attenuator
By designing a bidirectional low intermodulation attenuator, the problem of damage caused by confusion between input and output interfaces of fixed attenuators was solved, enabling bidirectional use and efficient testing, and improving the performance and signal quality of the communication system.
Patent Information
- Application Number
- CN202520168487.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-24
- Publication Date
- 2026-02-13
- Estimated Expiration
- 2035-01-24
AI Technical Summary
Existing fixed attenuators are prone to damage during use due to confusion between input and output interfaces, which affects performance and the accuracy of test results.
Design a bidirectional low intermodulation attenuator. By connecting a low intermodulation cable assembly to the output port and isolation resistor port of the coupler, the input port and coupling port become a bidirectional interface without input/output distinction, enabling bidirectional use. The heat dissipation performance is improved by the wire limiting ribs and thermal grease layer inside the housing.
It achieves bidirectional low intermodulation, avoids device damage caused by interface confusion, improves testing efficiency and device lifespan, and reduces intermodulation distortion and improves signal quality in communication systems.
Smart Images
Figure CN223911843U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of attenuator, concretely relates to a bidirectional low intermodulation attenuator. BACKGROUND
[0002] In electromagnetic compatibility test, the attenuator of different parameters is often connected at the input end of current probe, LISN, receiver, spectrum analyzer and other equipment, plays the role of adjusting signal intensity, improving impedance matching, protecting test equipment etc., thereby ensuring the accuracy and reliability of test result. The intermodulation value is proposed as an index in the early stage of the attenuator under the condition of guaranteeing normal conventional performance, the intermodulation value will affect the high-quality transmission of the whole communication link, and the intermodulation value is also an important reference value of product quality.
[0003] Some fixed attenuators on the market generally have 0.7~4GHz, 0.7~6GHz etc., the attenuator in a certain frequency band has multiple different attenuation values, different intermodulation values, and the input and output ports are marked. The attenuator with input and output ports marked is confused in daily long-term use, and once the input and output are confused, the internal resistance will be burned out, the attenuation value is abnormal, and the performance of the attenuator is affected, and the attenuator cannot be used normally.
[0004] Therefore, how to solve the above-mentioned problems of the prior art has become the subject to be studied and solved by the utility model. CONTENT OF THE UTILITY MODEL
[0005] The utility model aims at providing a bidirectional low intermodulation fixed attenuator without distinguishing input and output, which can be used bidirectionally.
[0006] To achieve the above-mentioned purpose, the utility model adopts the technical scheme that:
[0007] A bidirectional low intermodulation attenuator, comprising a coupler, the coupler has an input port, an output port, a coupling port and an isolation resistance port;
[0008] The output port is connected with a first low intermodulation load, the isolation resistance port is connected with a second low intermodulation load, the input port and the coupling port constitute a bidirectional interface without distinguishing input and output, and the two bidirectional interfaces are used as the input port and the output port of the fixed attenuator respectively.
[0009] Preferably, the first low intermodulation load adopts a low intermodulation cable assembly.
[0010] Preferably, the second low intermodulation load adopts a low intermodulation cable assembly.
[0011] Preferably, the coupling port is connected with a signal transmission line through a third low intermodulation load.
[0012] Preferably, the third low-intermodulation load adopts a low-intermodulation cable assembly.
[0013] Preferably, the bidirectional low-intermodulation fixed attenuator further comprises a box body, the coupler and the low-intermodulation cable assemblies are mounted in the box body, the input port and the output port of the third low-intermodulation load are two bidirectional interfaces, and the bidirectional interfaces are mounted on the outer wall of the box body.
[0014] Further preferably, the box body comprises a box body with upper and lower openings and cover plates detachably connected to the openings, and the outer wall of each cover plate is provided with a plurality of cooling fins.
[0015] Further preferably, the upper surface of the cover plate located below the box body is provided with two groups of wire limiting ribs for limiting and arranging the first low-intermodulation load and the second low-intermodulation load.
[0016] Further preferably, the number of the wire limiting ribs in each group is multiple, and the wire limiting ribs are distributed in a spiral or a back-to-back shape.
[0017] Further preferably, the first low-intermodulation load and the second low-intermodulation load are provided with a heat-conducting silicone grease layer on the upper and lower surfaces.
[0018] The working principle and advantages of the utility model are as follows:
[0019] The utility model discloses a low-intermodulation cable assembly connected to the output port and the isolation resistance port of the coupler, so that the input port and the coupling port of the coupler are bidirectional interfaces without input and output distinction, the two bidirectional interfaces become the input port and the output port of the attenuator, the whole attenuator is without input and output distinction and can be used bidirectionally, and bidirectional low-intermodulation and bidirectional high power are realized.
[0020] When the utility model attenuator is used for testing related communication equipment, wiring can be quickly connected, and the device is not burned out instantly after the input and output ports are connected incorrectly in the test, so that the test efficiency is improved, the maintenance rate of the device is reduced, and the utility model has considerable advantages. DRAWINGS
[0021] ATTACHMENT Figure 1 The structure block diagram of the utility model embodiment is shown in the figure;
[0022] ATTACHMENT Figure 2 The coupler line connection diagram of the utility model embodiment is shown in the figure;
[0023] ATTACHMENT Figure 3 The internal arrangement diagram of the utility model attenuator is shown in the figure;
[0024] ATTACHMENT Figure 4 The box body front view of the utility model embodiment is shown in the figure;
[0025] ATTACHMENTFigure 5 Experimental data diagram of a nominal 20db bidirectional attenuator of an embodiment of the present application.
[0026] In the above drawing: 1 coupler; 11 input port; 12 output port; 13 coupling port; 14 isolation resistance port; 15 first low intermodulation load; 16 second low intermodulation load; 17 third low intermodulation load; 2 box body; 21 box body; 22 cover plate; 23 heat sink; 24 wire limiting rib. DETAILED DESCRIPTION
[0027] The present application will be further described below in conjunction with the drawings and embodiments:
[0028] Embodiment: The present application will be clearly explained below by means of drawings and detailed description, and any person skilled in the art can change and modify the technology taught by the present application after understanding the embodiments of the present application, without departing from the spirit and scope of the present application.
[0029] The terms used herein are only for describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "this", "this", "this" and "the" as used herein also include the plural forms.
[0030] As for "first", "second", etc. used herein, it is not intended to specifically refer to the order or sequence, nor to limit the present application, but only to distinguish components or operations described by the same technical terms.
[0031] As for "connection" or "positioning" used herein, it can mean that two or more components or devices are in direct physical contact with each other, or are indirectly in physical contact with each other, or can mean that two or more components or devices are in operation or action with each other.
[0032] As for "contain", "include", "have" and the like used herein, they are all open terms, that is, they mean to include but not limited to.
[0033] As for the words (terms) used herein, except for special notes, they generally have the usual meaning of each word used in this field, in the content of the present application and in the special content. Some words used to describe the present application will be discussed below or elsewhere in this specification to provide additional guidance for those skilled in the art on the description of the present application.
[0034] As for "front", "back", "up", "down", "left", "right" and the like used herein, they are all directional words, which in the present application only illustrate the positional relationship between structures, and are not used to limit the protection scheme and the specific direction of the present application in actual implementation.
[0035] Referring to the drawings Figures 1-4The application discloses a bidirectional low-intermodulation attenuator which comprises a coupler 1 and a box 2.
[0036] The coupler 1 has an input port 11, an output port 12, a coupling port 13 and an isolation resistance port 14; the output port 12 is connected with a first low-intermodulation load 15, the isolation resistance port 14 is connected with a second low-intermodulation load 16, the input port 11 and the coupling port 13 are connected as a bidirectional interface without input and output distinction, and the two bidirectional interfaces are used as input and output ports of the fixed attenuator, that is, the two bidirectional interfaces can be used as input ports or output ports, and the two ports can realize low-intermodulation performance, thereby improving test efficiency and test effect in a specific use environment.
[0037] The first low-intermodulation load 15 and the second low-intermodulation load 16 are both low-intermodulation cable assemblies.
[0038] The coupling port 13 is connected with a signal transmission line of a wireless communication system, a satellite communication system, a broadcast television transmission system, a radar system or a test and measurement system through a third low-intermodulation load 17, and the third low-intermodulation load 17 can be a low-intermodulation cable assembly with a length of 100-200 mm.
[0039] When the low-intermodulation attenuator is connected with the signal transmission line of the wireless communication system, the low-intermodulation attenuator can effectively reduce intermodulation distortion caused by strong signal interference, thereby improving the performance and stability of the communication system.
[0040] When the low-intermodulation attenuator is connected with the signal transmission line of the satellite communication system, the low-intermodulation attenuator can improve the sensitivity and use capacity of the system, reduce the distortion rate and ensure the quality of signal transmission.
[0041] When the low-intermodulation attenuator is connected with the signal transmission line of the broadcast television transmission system, the low-intermodulation attenuator can reduce the interference of interference sources on signals, improve the quality and stability of the signals.
[0042] When the low-intermodulation attenuator is connected with the signal transmission line of the radar system, the low-intermodulation attenuator is used for reducing the power level of signals, realizing level balance and dynamic range expansion of a signal chain, providing impedance matching and ensuring the accuracy and stability of the radar system.
[0043] When the low intermodulation attenuator is connected with the signal transmission line of the electromagnetic compatibility test measurement system, the low intermodulation attenuator is used for calibrating and testing the radio frequency signal in the field of electromagnetic compatibility test measurement, so as to ensure the accuracy and reliability of the measurement.
[0044] Referring to the accompanying drawings Figure 3 The coupler 1 and each low intermodulation cable assembly are installed in the box body 2, the input port 11 and the output end of the third low intermodulation load 17 are two bidirectional interfaces, and the bidirectional interfaces are installed on the outer wall of the box body 2, so as to be convenient for being connected with the signal transmission line.
[0045] The box body 2 includes an upper and lower opening box body 21 and a cover plate 22 which is detachably connected at the two openings, and the outer wall of each cover plate 22 is provided with a plurality of cooling fins 23, which can help the cables and couplers 1 inside the box body 2 dissipate heat.
[0046] Since the first low intermodulation load 15 and the second low intermodulation load 16 generally adopt a low intermodulation cable assembly with a length of 20-30 m, the long cable is not conducive to heat dissipation when placed in disorder, and long-time placement may cause insulation aging, breakdown and other safety problems. Therefore, the upper surface of the cover plate 22 located below the box body 21 is provided with two groups of wire limiting ribs 24 for limiting and arranging the first low intermodulation load 15 and the second low intermodulation load 16. Each group of wire limiting ribs 24 is multiple in number and is distributed in a spiral or a back shape.
[0047] Through the wire limiting ribs 24 distributed in a spiral or a back shape, the low intermodulation cable assembly can be arranged along the outer wall of the wire limiting ribs 24, and the cable is arranged in a spiral or a back shape for heat dissipation.
[0048] In order to further accelerate the heat dissipation of the low intermodulation cable assembly, the first low intermodulation load 15 and the second low intermodulation load 16 are provided with a heat-conducting silicone layer on the upper and lower surfaces, and in actual processing, an appropriate amount of heat-conducting silicone is coated on the upper and lower surfaces of the low intermodulation cable assembly.
[0049] The attenuator can be used alone or installed in a related radio frequency unit for use. When the attenuator is connected with the signal transmission line, whether the input port and the output port are connected in positive or negative, when the signal is input into the attenuator, an attenuated signal will be output, and the signals connected in positive and negative are low intermodulation and accurate attenuation signals. In addition, the attenuator works normally during the test process without burning phenomenon.
[0050] The present embodiment provides experimental data of a nominal 20db bidirectional attenuator, as shown in Table 1. Figure 5The left data and the right data in the figure are two groups of attenuation data of the bidirectional attenuator, and through the two groups of data, it can be seen that when the signal is input into the bidirectional attenuator, an attenuated signal is output no matter the bidirectional attenuator is connected in series or in reverse.
[0051] In actual application, the length of the low-intermodulation cable assembly can be adjusted according to requirements, so that bidirectional attenuators with various attenuation amounts can be obtained.
[0052] The above examples are only for illustrating the technical concept and characteristics of the utility model, and the purpose is to enable persons skilled in the art to understand the content of the utility model and implement it, and it cannot limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit and essence of the utility model shall be covered within the protection scope of the utility model.
Claims
1. A bidirectional low intermodulation attenuator, characterized in that: Includes a coupler having an input port, an output port, a coupling port, and an isolation resistor port; The output port is connected to the first low intermodulation load, and the isolation resistor port is connected to the second low intermodulation load, forming a bidirectional interface between the input port and the coupling port without input / output distinction. The two bidirectional interfaces serve as the input and output ports of the fixed attenuator, respectively.
2. The bidirectional low intermodulation attenuator according to claim 1, characterized in that: The first low intermodulation load uses a low intermodulation cable assembly.
3. A bidirectional low intermodulation attenuator according to claim 2, characterized in that: The second low intermodulation load uses a low intermodulation cable assembly.
4. A bidirectional low intermodulation attenuator according to claim 3, characterized in that: The coupling port is connected to the signal transmission line via a third low intermodulation load.
5. A bidirectional low intermodulation attenuator according to claim 4, characterized in that: The third low intermodulation load uses a low intermodulation cable assembly.
6. A bidirectional low intermodulation attenuator according to claim 4, characterized in that: It also includes a housing, in which the coupler and each low intermodulation cable assembly are installed. The input port and the output of the third low intermodulation load are two bidirectional interfaces, which are installed on the outer wall of the housing.
7. A bidirectional low intermodulation attenuator according to claim 6, characterized in that: The box includes a box body with openings at the top and bottom, and cover plates that can be detachably connected to the two openings. The outer walls of the two cover plates are provided with multiple heat sinks.
8. A bidirectional low intermodulation attenuator according to claim 7, characterized in that: The cover plate located below the box body has two sets of conductor limiting ribs on its upper surface for limiting and organizing the first low intermodulation load and the second low intermodulation load.
9. A bidirectional low intermodulation attenuator according to claim 8, characterized in that: Each group of conductor limiting ribs consists of multiple ribs, which are distributed in a spiral or square shape.
10. A bidirectional low intermodulation attenuator according to claim 9, characterized in that: Thermally conductive silicone grease layers are provided on the upper and lower surfaces of the first low intermodulation load and the second low intermodulation load.