A frequency converter for a spacecraft

Abstract

The application discloses a frequency converter for a spacecraft, comprising a radio frequency module, a constant-temperature crystal oscillator, a local oscillator module, a power supply module, a local oscillator signal interconnection circuit, a power supply circuit, an upper pull-up strip and a lower bottom plate; wherein the radio frequency module, the constant-temperature crystal oscillator, the local oscillator module and the power supply module are combined together through the upper pull-up strip and the lower bottom plate, and the signal transmission and power supply among the radio frequency module, the constant-temperature crystal oscillator, the local oscillator module and the power supply module are realized through the local oscillator signal interconnection circuit and the power supply circuit located at both sides of the whole machine. The application is modularized according to functions, and the whole machine is integrated, so that the frequency converter is miniaturized and lightened, which is beneficial to the integrated development of various spacecrafts and provides support for the expansion of a load system.

Description

Technical Field

[0001] This invention belongs to the field of spacecraft payload design technology, and particularly relates to a frequency converter for spacecraft. Background Technology

[0002] With the development of aerospace technology, the operating range of spacecraft has gradually expanded from Earth orbit to Earth-Moon orbit and Mars orbit. The requirements for miniaturization, weight reduction, and reliability of spacecraft payloads are constantly increasing. As a widely used payload device in spacecraft, frequency converters face even more stringent requirements for miniaturization, weight reduction, and reliability. Current frequency converter designs have two main shortcomings: first, the extensive use of aluminum structural components, PCB circuits, and large-size packaged MHIC components results in large size, heavy weight, and high power consumption; second, due to the electrical assembly process for interconnecting MHIC components with PCB circuits, there is a risk of gain fluctuations in the frequency converter due to temperature changes. Summary of the Invention

[0003] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide a frequency converter for spacecraft. It is designed in a modular way according to function and the whole machine is interconnected and integrated, which realizes the miniaturization and lightweight of the frequency converter, which is conducive to the integrated development of various spacecraft and provides support for the expansion of payload systems.

[0004] To address the aforementioned technical problems, this invention discloses a frequency converter for spacecraft, comprising: a radio frequency module, a temperature-controlled crystal oscillator, a local oscillator module, a power supply module, a local oscillator signal interconnection circuit, a power supply circuit, an upper pull bar, and a lower base plate; wherein, the radio frequency module, the temperature-controlled crystal oscillator, the local oscillator module, and the power supply module are combined together via the upper pull bar and the lower base plate, and signal transmission and power supply between the radio frequency module, the temperature-controlled crystal oscillator, the local oscillator module, and the power supply module are achieved through the local oscillator signal interconnection circuit and the power supply circuit located on both sides of the entire unit.

[0005] In the aforementioned spacecraft frequency converter, the bottom plate serves as a fulcrum for fixing the bottom of each module, and the temperature-controlled crystal oscillator is mounted horizontally on the bottom plate. The radio frequency module, local oscillator module, and power supply module are mounted side by side above the temperature-controlled crystal oscillator, at the same height, and are fixed together by an upper pull bar. The local oscillator module is located between the radio frequency module and the power supply module. The power supply circuit is installed on the side of the frequency converter and is connected to the sides of the radio frequency module, temperature-controlled crystal oscillator, local oscillator module, and power supply module respectively, for securing the radio frequency module, temperature-controlled crystal oscillator, local oscillator module, and power supply module; at the same time, it outputs power from the power supply module to the radio frequency module, temperature-controlled crystal oscillator, and local oscillator module. The local oscillator signal interconnection circuit is installed on the side of the frequency converter and is connected to the sides of the radio frequency module, temperature-controlled crystal oscillator, and local oscillator module respectively, for securing the radio frequency module, temperature-controlled crystal oscillator, and local oscillator module; at the same time, it realizes the signal interconnection of the radio frequency module, temperature-controlled crystal oscillator, and local oscillator module.

[0006] In the aforementioned spacecraft frequency converter, the local oscillator signal interconnection circuit includes: a carrier, microstrip transmission line A, microstrip transmission line B, microstrip transmission line C, microstrip transmission line D, microstrip transmission line E, microstrip transmission line F, and microstrip transmission line G; wherein, microstrip transmission lines A, B, C, D, E, F, and G are bonded to the carrier with conductive adhesive; mounting holes are respectively provided on microstrip transmission lines A, B, C, D, E, F, and G for connecting the radio frequency module, the temperature-controlled crystal oscillator, and the local oscillator module.

[0007] In the aforementioned spacecraft frequency converter, the signal between the radio frequency module and the local oscillator module is connected through a microstrip transmission line of the local oscillator signal interconnection circuit via a vertical interconnection insulator, an interconnection gold strip, and an interconnection circuit of the local oscillator.

[0008] In the aforementioned spacecraft frequency converter, the microstrip transmission line adopts a T-junction high-low impedance line structure, which forms a vertical interconnect matching circuit with the vertical interconnect insulator.

[0009] In the aforementioned spacecraft frequency converter, W1=0.38mm, W2=0.5mm, L1=0.36mm, and L2=0.5mm; where W1 represents the width of the microstrip transmission line, W2 represents the width of the low-impedance matching line, L1 represents the length of the high-impedance matching line, and L2 represents the length of the low-impedance matching line.

[0010] In the aforementioned spacecraft frequency converter, the carrier material is aluminum.

[0011] In the aforementioned spacecraft frequency converter, the microstrip transmission lines A~G are 50-ohm microstrip transmission lines made of alumina ceramic substrate.

[0012] The aforementioned spacecraft frequency converter also includes: a flatness adjustment plate; wherein the tops of the radio frequency module, the local oscillator module, and the power supply module are fixed together by an upper pull strip; a flatness adjustment plate is provided between the radio frequency module, the local oscillator module, and the power supply module and the upper pull strip to adjust the gap between the radio frequency module, the local oscillator module, and the power supply module and the upper pull strip.

[0013] Among the aforementioned spacecraft frequency converters, the largest external dimensions are 106mm×72mm×68mm, and the weight is 0.48kg.

[0014] The present invention has the following advantages:

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] (1) This invention discloses a frequency converter for spacecraft, which features miniaturization and lightweight design. Compared with previous designs, the weight is reduced from 1.2 kg to 0.48 kg, and the volume is reduced to about 25% of the original design. The saved weight and volume can be used to increase the number of payloads or increase fuel capacity, which is beneficial to reducing launch costs and increasing the on-orbit operation time of spacecraft.

[0017] (2) This invention discloses a frequency converter for spacecraft. The integrated and modular design has higher reliability than the traditional design. The electrical performance indicators such as noise and gain fluctuation of the frequency converter will not change significantly. There is no gain jump phenomenon when the temperature changes, thus improving the reliability of the frequency converter. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a spacecraft frequency converter according to an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the structure of a local oscillator signal interconnection circuit in an embodiment of the present invention;

[0020] Figure 3 This is a three-dimensional diagram of a vertical interconnect matching circuit design model according to an embodiment of the present invention;

[0021] Figure 4 This is a plan view of a vertical interconnect matching circuit design model in an embodiment of the present invention;

[0022] Figure 5 This is a reflection coefficient curve of a vertical interconnect matching circuit in an embodiment of the present invention;

[0023] Figure 6 This is a gain versus temperature curve in an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments disclosed in the present invention will be described in further detail below with reference to the accompanying drawings.

[0025] One of the core ideas of this invention is to disclose a frequency converter for spacecraft, wherein the frequency converter adopts a modular design according to function and a vertical interconnection design for radio frequency signals.

[0026] The inverter adopts a modular design based on function: It is divided into functional modules such as an RF module, a temperature-controlled crystal oscillator module, a local oscillator module, and a power supply module, according to the functions of each circuit. This facilitates integrated and universal design, improves module reusability, shortens the design cycle, and enhances maintainability and production efficiency. Specifically, the RF module implements the frequency conversion and amplification of RF signals; the temperature-controlled crystal oscillator module provides a reference source for the inverter; the local oscillator module, using a phase-locked loop (PLL) frequency multiplier circuit, provides the local oscillator signal required for frequency conversion to the RF module through the reference source; and the power supply module provides secondary power to all parts of the inverter. All modules are combined via an upper pull strip and a lower base plate. This modular design allows for miniaturization of structural components, eliminating or shortening interconnecting cables between modules and components, thus reducing the size and weight of the inverter.

[0027] The radio frequency (RF) signal employs a vertical interconnect design: Due to miniaturization, the isolation requirements between signals of different functions and frequencies during signal transmission between the RF module and the local oscillator module have been altered. Signal transmission is achieved through vertical interconnection between module cavities using insulators, and a matching design has been implemented for the vertical insulators on the signal transmission substrate. This design ensures that the inverter's electrical performance indicators, such as noise and gain fluctuations, do not change significantly with temperature variations, thus improving the inverter's reliability.

[0028] like Figure 1 In this embodiment, the spacecraft frequency converter includes: a radio frequency module 1, a temperature-controlled crystal oscillator 2, a local oscillator module 3, a power supply module 4, a local oscillator signal interconnection circuit 5, a power supply circuit 6, an upper pull bar 7, and a lower base plate 8. The radio frequency module 1, the temperature-controlled crystal oscillator 2, the local oscillator module 3, and the power supply module 4 are combined together via the upper pull bar 7 and the lower base plate 8. Signal transmission and power supply between the radio frequency module 1, the temperature-controlled crystal oscillator 2, the local oscillator module 3, and the power supply module 4 are achieved through the local oscillator signal interconnection circuit 5 and the power supply circuit 6 located on both sides of the unit.

[0029] In this embodiment, the lower base plate 8 serves as a fulcrum for fixing the bottom of each module, and the thermostatic crystal oscillator 2 is mounted horizontally on the lower base plate 8. The radio frequency module 1, the local oscillator module 3, and the power supply module 4 are mounted side by side above the thermostatic crystal oscillator 2 at the same height and are fixed together by the upper pull strip 7; the local oscillator module 3 is located between the radio frequency module 1 and the power supply module 4. The power supply circuit 6 is installed on the side of the inverter and is connected to the sides of the radio frequency module 1, the thermostatic crystal oscillator 2, the local oscillator module 3, and the power supply module 4 respectively, for securing the radio frequency module 1, the thermostatic crystal oscillator 2, the local oscillator module 3, and the power supply module 4; at the same time, it outputs the power supply from the power supply module 4 to the radio frequency module 1, the thermostatic crystal oscillator 2, and the local oscillator module 3. The local oscillator signal interconnection circuit 5 is installed on the side of the inverter and is connected to the sides of the radio frequency module 1, the thermostatic crystal oscillator 2, and the local oscillator module 3 respectively, for securing the radio frequency module 1, the thermostatic crystal oscillator 2, and the local oscillator module 3; at the same time, it realizes the signal interconnection of the radio frequency module 1, the thermostatic crystal oscillator 2, and the local oscillator module 3. This method changes the previous design that used semi-steel cables for signal interconnection and low-frequency cable networks for secondary power supply, thus reducing the overall size of the unit. The inverter's maximum dimensions are 106mm × 72mm × 68mm, and its weight is 0.48kg.

[0030] In this embodiment, as Figure 2 As shown, the local oscillator signal interconnection circuit 5 may specifically include: a carrier 51, microstrip transmission lines A52, B53, C54, D55, E56, F57, and G58. Microstrip transmission lines A52, B53, C54, D55, E56, F57, and G58 are bonded to the carrier 51 using conductive adhesive. Mounting holes 59 are provided on each of the microstrip transmission lines A52, B53, C54, D55, E56, F57, and G58, and are used to connect the RF module 1, the temperature-controlled crystal oscillator 2, and the local oscillator module 3. The function of the local oscillator module in a frequency converter is to provide a local oscillator signal for the frequency conversion function of the radio frequency module. The local oscillator signal has a high frequency and a wide coverage band, typically between 4GHz and 30GHz. In previous designs, the local oscillator signal was transmitted via semi-steel cables. These semi-steel cables for satellite applications are time-consuming, costly, and space-consuming. However, the local oscillator signal interconnection circuit described in this invention uses a microstrip line + aluminum carrier structure, enabling local oscillator signal transmission covering DC to 35GHz. It is compactly installed with the frequency converter, featuring small size, low cost, simple installation, and good repairability.

[0031] Preferably, the signal between the RF module 1 and the local oscillator module 3 is connected to the microstrip transmission line of the local oscillator signal interconnection circuit 5 via the vertical interconnection insulator 9, the interconnection gold strip 10, and the interconnection circuit 5. For example... Figure 3 As shown, VHg Indicates the height of the vertically interconnected insulator. VHp Indicates the height of the inner conductor of the vertical interconnect insulator. Hsub Indicates the thickness of the microstrip transmission line. Gg This indicates the arch height of the interconnect gold strip. Furthermore, the microstrip transmission line adopts a T-junction high-low impedance line structure (a T-structure composed of a high impedance line and a low impedance line), which, together with the vertical interconnect insulator 9, forms a vertical interconnect matching circuit (50-ohm mother impedance matching). Figure 4 As shown, W1 represents the width of the microstrip transmission line, W2 represents the width of the low impedance matching line, L1 represents the length of the high impedance matching line, and L2 represents the length of the low impedance matching line.

[0032] Preferably, the dimensions of the vertical interconnect matching circuit are simulated and optimized, such as... Figure 5 As shown, this vertical interconnect matching circuit achieves impedance matching covering DC~35GHz, and the circuit's reflection coefficient S(1,1) can be less than -20dB.

[0033] Preferably, the carrier 51 is made of aluminum. The microstrip transmission lines A to G are 50-ohm microstrip transmission lines made of alumina ceramic substrates.

[0034] In this embodiment, the spacecraft frequency converter further includes a flatness adjustment plate. The tops of the radio frequency module 1, the local oscillator module 3, and the power supply module 4 are fixed together by an upper pull strip 7. A flatness adjustment plate is provided between the radio frequency module 1, the local oscillator module 3, and the power supply module 4 and the upper pull strip 7 to adjust the gap between them.

[0035] In this embodiment, a temperature test was conducted on the spacecraft frequency converter, and the gain versus temperature curve is shown below. Figure 6 As shown, the gain changes smoothly and continuously throughout the entire operating temperature range, without any jumps.

[0036] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

[0037] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A frequency converter for a spacecraft, characterized by include: The radio frequency module (1), the temperature-controlled crystal oscillator (2), the local oscillator module (3), the power supply module (4), the local oscillator signal interconnection circuit (5), the power supply circuit (6), the upper pull bar (7), and the lower base plate (8) are combined together by the upper pull bar (7) and the lower base plate (8). The signal transmission and power supply between the radio frequency module (1), the temperature-controlled crystal oscillator (2), the local oscillator module (3), and the power supply module (4) are realized by the local oscillator signal interconnection circuit (5) and the power supply circuit (6) located on both sides of the whole machine. The bottom plate (8) serves as a support point for fixing the bottom of each module. The thermostatic crystal oscillator (2) is installed horizontally on the bottom plate (8). The radio frequency module (1), the local oscillator module (3), and the power supply module (4) are installed side by side above the thermostatic crystal oscillator (2) at the same height and are fixed together by the upper pull strip (7). The local oscillator module (3) is located between the radio frequency module (1) and the power supply module (4). The power supply circuit (6) is installed on the side of the inverter and is connected to the sides of the radio frequency module (1), the thermostatic crystal oscillator (2), the local oscillator module (3), and the power supply module (4) respectively, for fastening the injection. The inverter consists of a frequency converter module (1), a temperature-controlled crystal oscillator (2), a local oscillator module (3), and a power supply module (4). Simultaneously, the power supply from the power supply module (4) is output to the frequency converter module (1), the temperature-controlled crystal oscillator (2), and the local oscillator module (3). A local oscillator signal interconnection circuit (5) is installed on the side of the inverter unit and connected to the sides of the frequency converter module (1), the temperature-controlled crystal oscillator (2), and the local oscillator module (3) respectively, for securing the frequency converter module (1), the temperature-controlled crystal oscillator (2), and the local oscillator module (3). Simultaneously, it enables signal interconnection between the frequency converter module (1), the temperature-controlled crystal oscillator (2), and the local oscillator module (3). The local oscillator signal interconnection circuit (5) includes: a carrier (51), microstrip transmission line A (52), microstrip transmission line B (53), microstrip transmission line C (54), microstrip transmission line D (55), microstrip transmission line E (56), microstrip transmission line F (57), and microstrip transmission line G (58); wherein, microstrip transmission line A (52), microstrip transmission line B (53), microstrip transmission line C (54), microstrip transmission line D (55), microstrip transmission line E (56), and microstrip transmission line G (58) are connected. Transmission line F (57) and microstrip transmission line G (58) are bonded to the carrier (51) with conductive adhesive; microstrip transmission lines A (52), B (53), C (54), D (55), E (56), F (57) and G (58) are respectively provided with mounting holes (59), which are used to connect the radio frequency module (1), the temperature-controlled crystal oscillator (2) and the local oscillator module (3); The signal between the radio frequency module (1) and the local oscillator module (3) is connected to the microstrip transmission line of the local oscillator signal interconnection circuit (5) through the vertical interconnection insulator (9), the interconnection gold strip (10); The microstrip transmission line adopts a T-junction high and low impedance line structure, which forms a vertical interconnect matching circuit with the vertical interconnect insulator (9).

2. The spacecraft frequency converter according to claim 1, characterized in that, W1=0.38mm, W2=0.5mm, L1=0.36mm, L2=0.5mm; where W1 represents the width of the microstrip transmission line, W2 represents the width of the low impedance matching line, L1 represents the length of the high impedance matching line, and L2 represents the length of the low impedance matching line.

3. The spacecraft frequency converter according to claim 1, characterized in that, The carrier (51) is made of aluminum.

4. The spacecraft frequency converter according to claim 1, characterized in that, Microstrip transmission lines A~G are 50-ohm microstrip transmission lines made of alumina ceramic substrate.

5. The spacecraft frequency converter according to claim 1, characterized in that, Also includes: Flatness adjustment piece; wherein, the top of the RF module (1), the local oscillator module (3) and the power module (4) are fixed together by the upper pull strip (7); a flatness adjustment piece is provided between the RF module (1), the local oscillator module (3) and the power module (4) and the upper pull strip (7) to adjust the gap between the RF module (1), the local oscillator module (3) and the power module (4) and the upper pull strip (7).

6. The spacecraft frequency converter according to claim 1, characterized in that, The inverter has a maximum external dimension of 106mm×72mm×68mm and a weight of 0.48kg.

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