Flexible packaging shell structure capable of covering C-Ka frequency band

Abstract

The invention discloses a flexible packaging shell structure capable of covering a C-Ka frequency band, which comprises a shell structure main body, the front surface of the shell structure main body is provided with an input cavity and an output cavity, and the back surface of the shell structure main body is provided with a radio frequency air-tight sealing cavity. Wherein the input cavity leads to the radio frequency air-tight sealed cavity through the first vertical transition channel, and the radio frequency air-tight sealed cavity leads to the output cavity through the second vertical transition channel, so that signals can only be transmitted through the vertical transition structure, electromagnetic radiation isolation is realized, and the independence of the two regions is ensured at the same time; the packaging unification of the C-Ka frequency band LCAMP radio frequency part is realized, the types of components are effectively reduced, the process is simplified, the cost is reduced, and the cost-effectiveness ratio of the system is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of radio frequency microwave components and relates to a packaging shell structure, and in particular to a flexible packaging shell structure capable of covering a C-Ka frequency band. Background Art

[0002] In microwave systems, the size of the microwave device's operating frequency determines the size of the device. Generally, the lower the frequency, the larger the size of the device. When designing microwave components, it is necessary to design the device or component structure package according to the size of the device and the operating frequency required by the task. With the development of integrated circuit technology, the size of chips has been continuously miniaturized. The low noise amplifier (LNA) of the Q band (operating frequency 40G) and the low noise amplifier of the L band (operating frequency 1G) are not much different in size, which makes the frequency compatibility of the RF packaging cavity continue to improve, and the RF packaging of the high frequency band can be backward compatible. However, some microwave devices, such as microstrip surface mount isolators and waveguide devices, are limited by materials and processes and cannot be chip-based and miniaturized. These devices have large differences in size in different operating frequency bands. How to make these devices frequency compatible in RF packaging design and achieve unified packaging is the key research direction of microwave circuit design engineering. Summary of the invention

[0003] In view of the deficiencies in the prior art, an object of the present invention is to provide a packaging shell structure to solve the technical problem that the electromagnetic radiation isolation effect of the packaging shell structure in the prior art needs to be further improved.

[0004] Another object of the present invention is to provide a flexible packaging shell structure that can cover the C-Ka frequency band, thereby solving the technical problem that the packaging shell structure in the prior art is difficult to cover the C-Ka frequency band.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above problems:

[0006] A packaging shell structure comprises a shell structure main body, an input cavity and an output cavity are arranged on the front side of the shell structure main body, and a radio frequency airtight packaging cavity is arranged on the back side of the shell structure main body.

[0007] The input cavity and the RF airtight packaging cavity are connected through a first vertical transition channel, the central axis of the first vertical transition channel is perpendicular to the central plane of the input cavity, and the central axis of the first vertical transition channel is perpendicular to the central plane of the RF airtight packaging cavity.

[0008] The output cavity and the RF airtight packaging cavity are connected through a second vertical transition channel, the central axis of the second vertical transition channel is perpendicular to the central plane of the output cavity, and the central axis of the second vertical transition channel is perpendicular to the central plane of the RF airtight packaging cavity.

[0009] The present invention also has the following technical features:

[0010] The radio frequency airtight packaging cavity is divided into six independent small cavities.

[0011] The RF airtight packaging cavity has a cavity width of 4.6 mm and a height of 2.6 mm.

[0012] A movable shielding frame is detachably mounted on the shell structure body surrounding the input cavity and the output cavity.

[0013] The material of the movable shielding frame is the same as that of the shell structure body.

[0014] Compared with the prior art, the present invention has the following technical effects:

[0015] (I) The present invention proposes to isolate the input cavity and the output cavity from the RF airtight packaging cavity through a coaxial vertical transition structure for electromagnetic radiation, so that the signal can only be transmitted through the vertical transition structure, thereby ensuring the independence of the two areas, effectively reducing the types of components, simplifying the process, reducing costs, and improving the system cost-effectiveness.

[0016] (II) The active shielding frame proposed in the present invention can effectively achieve frequency compatibility with large-sized microwave devices such as microstrip surface-mount isolators, and realize the packaging uniformity of the RF part of the C~Ka band linear channel amplifier (LCAMP).

[0017] (III) The flexible packaging shell structure proposed in the present invention adopts a unified packaging shell to effectively reduce the types of packaging, ensure that microwave component products of the same type but different frequencies are completely consistent in the electromechanical and thermal interfaces, reduce the cost problems caused by repeated design and inconsistent materials, and lay the foundation for low-cost and mass production of satellites. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of the basic structure of the package shell.

[0019] FIG. 2( a ) is a front view schematic diagram of the composition principle of the package shell.

[0020] FIG. 2( b ) is a side view schematically showing the composition principle of the package shell.

[0021] FIG. 2( c ) is a schematic diagram of the reverse side of the packaging shell composition principle.

[0022] Figure 3(a) is a schematic diagram of a Class A active shielding frame structure.

[0023] Figure 3(b) is a schematic diagram of a Class B active shielding frame structure.

[0024] FIG4( a ) is a schematic diagram of the installation of a Class A active shielding frame structure and a packaging housing.

[0025] FIG4( b ) is a schematic diagram of the installation of the Class B active shielding frame structure and the packaging housing.

[0026] Figure 5 Schematic diagram of the principle block diagram of the linearized traveling wave tube amplifier.

[0027] Figure 6 Compatible photos of different frequencies for active shielding frames.

[0028] Figure 7 Schematic diagram of the partitioning of the coaxial vertical transition structure.

[0029] The meanings of the various numbers in the figure are: 1-shell structure body, 2-input cavity, 3-output cavity, 4-RF airtight packaging cavity, 5-first vertical transition channel, 6-second vertical transition channel, 7-active shielding frame, 8-microstrip surface mount isolator, 9-microwave RF chip.

[0030] The specific contents of the present invention are further described in detail below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0031] It should be noted that, unless otherwise specified, all components and devices in the present invention are components and devices known in the prior art.

[0032] In the present invention, the linearized traveling wave tube amplifier is composed of three parts: a linearized channel amplifier, a traveling wave tube power supply and a traveling wave tube. Figure 5 The RF part of the linear channel amplifier consists of three parts: RF components, packaging shell and control circuit.

[0033] Different satellites have different operating frequencies due to different mission functions. The present invention mainly designs the packaging shell and frequency compatibility of the linearized channel amplifier (LCAMP) in the linearized traveling wave tube amplifier, and realizes the packaging uniformity of the radio frequency part of the linearized channel amplifier (LCAMP) covering the C~Ka frequency band.

[0034] In accordance with the above technical scheme, specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical scheme of this application fall within the protection scope of the present invention.

[0035] Example:

[0036] This embodiment provides a packaging shell structure, such as Figure 1 to Figure 2(c) As shown, it includes a shell structure body 1, wherein an input cavity 2 and an output cavity 3 are arranged on the front side of the shell structure body 1, and a radio frequency airtight packaging cavity 4 is arranged on the back side of the shell structure body 1.

[0037] The input cavity 2 and the RF airtight packaging cavity 4 are connected through a first vertical transition channel 5, and the central axis of the first vertical transition channel 5 is perpendicular to the central plane of the input cavity 2, and the central axis of the first vertical transition channel 5 is perpendicular to the central plane of the RF airtight packaging cavity 4.

[0038] The output cavity 3 and the RF airtight packaging cavity 4 are connected through a second vertical transition channel 6, and the central axis of the second vertical transition channel 6 is perpendicular to the central plane of the output cavity 3 and the central axis of the second vertical transition channel 6 is perpendicular to the central plane of the RF airtight packaging cavity 4.

[0039] In this embodiment, the signal can only be transmitted through the first vertical transition channel 5 and the second vertical transition channel 6 to achieve electromagnetic radiation isolation.

[0040] In this embodiment, the RF airtight packaging cavity 4 is divided into six independent small cavities. Each small cavity is independent, which can prevent microwave crosstalk between internal levels. When the cavity is laid out, the power supply insulator is arranged on one side of the cavity, which can effectively increase the chip cloth width when the cavity width is constant. By adopting the above-mentioned various measures, the frequency band of the product operation is widened, the link length that can be accommodated is lengthened, and the applicability of the RF airtight packaging cavity 4 is effectively improved, so that it can be applied to various types of product designs.

[0041] In this embodiment, the input cavity 2 and the output cavity 3 are used to package the microstrip surface mount isolator 8 ; the RF airtight packaging cavity 4 is used to package the microwave RF chip 9 .

[0042] In this embodiment, the sizes of the microstrip surface mount isolators 8 are different. For low-power microwave modules, a low-power microstrip surface mount isolator 8 needs to be added to the front stage of the RF airtight packaging cavity 4 to improve the standing wave. At the same time, the low-power microwave amplifier is protected to prevent excessive reflected power from causing amplifier damage or failure in the case of mismatch. At this time, the reflected power will be absorbed by the load of the microstrip surface mount isolator 8.

[0043] As a preferred solution of this embodiment, the width of the RF airtight packaging cavity 4 is 4.6 mm and the height is 2.6 mm.

[0044] In this embodiment, the RF airtight packaging cavity 4 is airtight by using a laser welding cover plate. When designing the RF airtight packaging cavity 4, compatibility with different frequencies must be considered. Therefore, after simulation calculation, it can be obtained from Table 1 that the cavity width of the RF airtight packaging cavity 4 is 4.6mm, the height is 2.6mm, and the lowest resonant frequency is calculated to be 33.6GHz, which can meet the design requirements of Ka-band products. At the same time, the cavity width can also accommodate microwave devices as low as C-band, and has good versatility.

[0045] Table 1 Calculation results of the resonance frequencies of different cavities

[0046] Cavity No. Cavity size mm Cavity resonance frequency GHz Front cavity 1 18.35×4.6×2.6 33.6 Front cavity 2 18.35×4.6×2.6 33.6 Front cavity 3 19.5×4.6×2.6 33.6 Front cavity 4 19.5×4.6×2.6 33.6 Front cavity 5 18.35×4.6×2.6 33.6 Front cavity 6 18.35×4.6×2.6 33.6

[0047] As a preferred solution of this embodiment, a movable shielding frame 7 is detachably mounted on the shell structure main body 1 around the input cavity 2 and the output cavity 3 .

[0048] In the present invention, the sizes of microstrip surface mount isolators 8 of different frequency bands are different. According to the installation requirements, the resonant frequency simulation is performed on the structure that meets the installation requirements. As shown in Table 1, the simulation shows that the resonant frequencies of different cavity sizes are different. The larger the size, the smaller the resonant frequency. The lowest resonant frequency of the cavity that meets the assembly and operation of the microstrip surface mount isolator of the C band is 12.57GHz, and the lowest resonant frequency of the cavity that meets the assembly and operation of the microstrip surface mount isolator of the X band is 16GHz. It cannot meet the requirements of the operating frequency of the Ku (above 12GHz) and Ka bands (above 18GHz), so that products of different frequencies must use different packages and corresponding frequency structures, which seriously restricts the product standardization and low-cost development goals. Therefore, it is necessary to set an active shielding frame 7 to meet the requirements of the operating frequency of the Ku (above 12GHz) and Ka bands (above 18GHz).

[0049] Table 2 Calculation results of resonant frequency of different sizes

[0050]

[0051] In this embodiment, the active shielding frame 7 is a structure for radio frequency shielding of the input cavity 2 and the output cavity 3 according to the size and operating frequency of the microstrip surface mount isolator 8. Figure 3(a) to Figure 4(b) As shown, when the product operating frequency is 10 GHz and below, use Class A active shielding frame; when the product operating frequency is 10 GHz and above, use Class B active shielding frame.

[0052] In this embodiment, the design of the movable shielding frame 7 adopts a known simulation method to perform accurate electromagnetic simulation to ensure the shielding effect and frequency compatibility.

[0053] As a preferred solution of this embodiment, the material of the movable shielding frame 7 is the same as that of the shell structure body 1, which is used to ensure the same thermal expansion coefficient and ensure that the movable shielding frame 7 and the shell structure body 1 can have good contact within a wide temperature range.

[0054] In this embodiment, the movable shielding frame 7 is connected and fastened to the shell structure main body 1 by means of screws, thereby ensuring the flexibility of operation of the movable shielding frame 7 .

[0055] In this embodiment, the use of the movable shielding frame 7 realizes the frequency coverage of 3 to 30 GHz in a package shell for the application of the linear channel amplifier (LCAMP) radio frequency module.

[0056] like Figure 6 As shown, for the shielding frame technology with flexible frequency matching, by setting several sets of movable shielding frames 7 on the outer shell of the RF airtight packaging cavity 4, through accurate simulation calculation, the frequency compatibility of large-sized microwave devices such as microstrip surface mount isolators 8 can be effectively achieved. Figure 7 As shown, after the signal passes through the microstrip surface mount isolator 8 in the input cavity 2, it enters the microwave RF chip 9 in the RF airtight packaging cavity 4 through the microwave structure of the coaxial vertical transition structure, and then enters the microstrip surface mount isolator 8 in the output cavity 3 through the coaxial vertical transition structure after the microwave RF chip 9, thereby realizing the unified packaging shell.

[0057] The packaging design method proposed in this embodiment has been applied to C-Ka band linear traveling wave tube amplifiers in communication satellites such as CS9C and CS10R. After use, one packaging shell achieves frequency coverage of 3-30 GHz, and the linear traveling wave tube amplifiers in different frequency bands have the same appearance.

Claims

1. A packaging shell structure, comprising a shell structure body (1), characterized in that: An input cavity (2) and an output cavity (3) are arranged on the front side of the shell structure main body (1), and a radio frequency airtight packaging cavity (4) is arranged on the back side of the shell structure main body (1); The input cavity (2) and the radio frequency airtight packaging cavity (4) are connected via a first vertical transition channel (5), the central axis of the first vertical transition channel (5) is perpendicular to the central plane of the input cavity (2), and the central axis of the first vertical transition channel (5) is perpendicular to the central plane of the radio frequency airtight packaging cavity (4); The output cavity (3) and the RF airtight packaging cavity (4) are connected via a second vertical transition channel (6), the central axis of the second vertical transition channel (6) is perpendicular to the central plane of the output cavity (3), and the central axis of the second vertical transition channel (6) is perpendicular to the central plane of the RF airtight packaging cavity (4).

2. The package shell structure according to claim 1, characterized in that: The radio frequency airtight packaging cavity (4) is divided into six independent small cavities.

3. The package shell structure according to claim 1, characterized in that: The radio frequency airtight packaging cavity (4) has a cavity width of 4.6 mm and a height of 2.6 mm.

4. The package shell structure according to claim 1, characterized in that: A movable shielding frame (7) is detachably mounted on the shell structure main body (1) surrounding the input cavity (2) and the output cavity (3).

5. The package shell structure according to claim 4, characterized in that: The material of the movable shielding frame (7) is the same as that of the shell structure body (1).

Images