Design method of low-cost dual-channel frequency conversion assembly with local oscillation source

Abstract

The invention discloses a design method of a low-cost dual-channel frequency conversion assembly with a local oscillator source, and the method comprises the steps: enabling a frequency conversion channel, a local oscillator power division network and a local oscillator source circuit to be integrated into a box body under the condition that the height of the box body is not changed; radio frequency cables between the local oscillator source module and the local oscillator power division network module and between the local oscillator power division network module and the frequency conversion channel are omitted, the assembly steps of the system are simplified, the assembly speed of the whole module is increased, the cost of the whole system is reduced, and meanwhile the area occupied by the whole system is effectively reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of microwave communication, in particular to a design method of a low-cost dual-channel frequency conversion component in the field of reconnaissance. Background Art

[0002] In recent years, military and aerospace electronic equipment has developed towards "light, thin, short and small", and the demand for high density, high integration and low cost of its circuit components has become more and more urgent. As the core part of the microwave system of a ground electronic reconnaissance equipment, the dual-channel broadband frequency conversion component including the local oscillator source has important significance for its low-cost design.

[0003] At present, for multi-channel frequency conversion systems, multiple frequency conversion channels are integrated into one box, with the front side being the frequency conversion channel using micro-assembly technology, and the back side being designed as the power supply and power filter circuit. The local oscillator signal is generated by a separate local oscillator source module. The local oscillator signal power division network is designed using a separate box. The frequency conversion channel module and the local oscillator signal power division network module are connected via an RF cable. Since the frequency conversion channel and the power division network are designed using two modules respectively, and a local oscillator source module is required to provide the local oscillator signal, the entire system occupies a large area, and the three modules are connected by cables, and a separate RF cable needs to be made, which increases the assembly time and assembly cost of the entire system. Summary of the invention

[0004] The purpose of the present invention is to provide a low-cost design method for a dual-channel frequency conversion component with its own local oscillator source. While ensuring that the height of the box body remains unchanged, the frequency conversion channel, the local oscillator power division network, and the local oscillator source circuit are integrated into one box body, and the radio frequency cables between the local oscillator source module and the local oscillator power division network module, and between the local oscillator power division network module and the frequency conversion channel are omitted, thereby simplifying the assembly steps of the system, accelerating the assembly speed of the entire module, reducing the cost of the entire system, and effectively reducing the area occupied by the entire system.

[0005] The technical solution to realize the present invention is: a design method of a low-cost dual-channel frequency conversion component with its own local oscillator source, the steps are as follows:

[0006] S1: According to the size and function requirements of the dual-channel frequency conversion component in the RF receiver, combined with the component budget, the functional circuits that the dual-channel frequency conversion component with its own local oscillator source needs to include are formulated as follows:

[0007] Since the dual-channel frequency conversion component with its own local oscillator source is limited to a size of 103×87×10mm 3The box structure is designed. The dual-channel frequency conversion component with its own local oscillator source includes two independent frequency conversion channels, a local oscillator source circuit, a local oscillator power division circuit, and a power supply filter and control circuit. The two independent frequency conversion channels down-convert the received two 6-18GHz RF signals to an intermediate frequency. The local oscillator source circuit is used to generate the local oscillator signal required by the frequency conversion channel, and filter and amplify the local oscillator signal. The local oscillator power division circuit is used to power divide the local oscillator signal generated by the local oscillator source circuit and send it to the two frequency conversion channels respectively. The power supply filter and control circuit are used to stabilize the voltage of the input frequency conversion component to the voltage value required by the device, and perform filtering processing. The control circuit decodes the input control signal and sends it to the frequency conversion channel and the local oscillator source circuit respectively, and then goes to step S2.

[0008] S2: According to the functional indicator requirements of the dual-channel frequency conversion component in the radio frequency receiver, the dual-channel frequency conversion component is analyzed and a corresponding solution block diagram is formulated, and then the process goes to step S3.

[0009] S3: According to the scheme block diagram in step S2, determine the assembly method of each part of the circuit and the packaging of the devices used. The frequency conversion circuit on the front of the component, the local oscillator filter and gain adjustment circuit, and the local oscillator power division circuit use bare chips combined with micro-assembly technology. The local oscillator core board uses LMX2595 to generate the local oscillator signal. LMX2595 and the peripheral circuit are assembled using a separate printed circuit board combined with SMT technology and installed in the component by screws. The power supply filter and control circuit uses a low-profile surface-mount regulator, an STM32 microcontroller, a low-profile packaged serial-to-parallel chip, and 0603 packaged capacitors and resistors combined with SMT technology, and then proceeds to step S4.

[0010] S4: According to the assembly form and device packaging determined in S3, and according to the required size of the components, the front side of the frequency conversion component is divided into a frequency conversion channel, a local oscillator core circuit, a local oscillator filter and gain adjustment circuit, and a local oscillator power division circuit according to function, and then the process goes to step S5.

[0011] S5: According to the schematic diagram, calculate the height of the structural parts, printed circuit boards, and devices that make up each part of the component circuit. Determine that the front micro-assembly circuit part uses a RO5880 double-sided printed circuit board with a thickness of 0.254mm. The front of the frequency conversion component contains 2 independent frequency conversion channels, a local oscillator filter and gain adjustment circuit, and a local oscillator power division circuit. The front of the frequency conversion component also contains a local oscillator core board with a thickness of 1mm. The maximum height of the device on it is 1mm. The structural parts of the core board part are 0.4mm lower than the micro-assembly part circuit. The thickness of the back cavity of the component is 3.1mm, and the back uses a 4-layer printed circuit board with a thickness of 0.8mm and a material of FR4. Go to step S6.

[0012] S6: Draw the corresponding PCB layout according to the links, devices and circuit areas determined in S4 and S5, and proceed to step S7.

[0013] S7: According to the device height determined in S5, the circuit functional area determined in S5 and S6, and the layout design, the cavity height distribution of the component is determined, and the structure is designed, and then the process goes to step S8.

[0014] S8: Process and manufacture the frequency conversion components according to the designed printed circuit board drawing and structural diagram.

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

[0016] (1) The local oscillator integrated dual-channel frequency conversion component integrates two frequency conversion channels, and the module height is 10mm. Compared with the previous independent single-channel frequency conversion module, not only the total volume is more compact, but the height is also reduced to 10mm.

[0017] (2) The local oscillator integrated dual-channel frequency conversion component integrates the local oscillator source module inside the component and uses the partition wall between different channels of the front microwave circuit as the cavity, eliminating the need for separate assembly of the local oscillator source component, the local oscillator power subassembly, and the cables connecting the components, thereby reducing the weight of the entire component, simplifying the assembly process, reducing processing costs, and improving production and assembly efficiency.

[0018] (3) LMX2595 is selected as the core component of the local oscillator circuit, which effectively reduces the processing and manufacturing cost of the component while ensuring the integration of the component.

[0019] (4) The frequency conversion channel and local oscillator source are each controlled by a separate serial signal, which reduces the mutual interference between different RF circuits.

[0020] (5) Each circuit is separated into separate cavities, and circuits with different functions are isolated through structural parts to reduce mutual interference between circuits with different functions.

[0021] (6) The local oscillator core board is designed as a separate universal module to facilitate calling by different components. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a functional block diagram of a frequency conversion component implemented in an embodiment of the present invention.

[0023] Figure 2 This is a block diagram of the principles implemented by the present invention.

[0024] Figure 3 This is a functional partition diagram of the front circuit of the present invention.

[0025] Figure 4 Control signal flow diagram in the present invention. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0028] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation" and the like should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; "connection" can be a mechanical connection or an electrical connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0030] The following will further introduce the specific implementation method, as well as the technical difficulties and inventive points of this invention in combination with this design example.

[0031] The present invention mainly conducts in-depth research on a low-cost dual-channel frequency conversion component with a local oscillator source for ground electronic reconnaissance equipment. By adopting a local oscillator core board with LMX2595 as the core, combined with a local oscillator filter and gain adjustment circuit and a local oscillator power division circuit, the local oscillator source and the frequency conversion channel are integrated, effectively reducing the volume of the microwave subsystem, achieving system miniaturization while reducing the hardware cost of the entire component. Compared with the traditional separate design in terms of volume, weight, component integration mode and cost, it has obvious advantages and meets the needs of actual engineering.

[0032] The design method adopted in the present invention integrates the local oscillator source circuit, the local oscillator power division circuit and the radio frequency channel into one module, reduces the interconnection cables between different modules, and improves the integration of the module. At the same time, because the LMX2595 chip is used as a low-cost frequency hopping source, the manufacturing cost of the entire module is effectively reduced. The LMX2595 chip is assembled separately on a printed circuit board, which is conducive to reducing hardware costs and design complexity, improving assembly speed, and reducing assembly difficulty.

[0033] The implementation of the present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

[0034] Combination Figure 1 to Figure 4 The design method of a low-cost dual-channel frequency conversion component with a local oscillator source described in the present invention comprises the following steps:

[0035] S1: According to the size and function requirements of the dual-channel frequency conversion component in the RF receiver, combined with the component budget, formulate the functional circuits that the dual-channel frequency conversion component with its own local oscillator source needs to include, such as Figure 1 As shown, the details are as follows:

[0036] The dual-channel frequency conversion component with its own local oscillator source is limited to a size of 103×87×10mm 3 in the box structure.

[0037] The dual-channel frequency conversion component with its own local oscillator source includes two independent frequency conversion channels, one local oscillator source circuit, one local oscillator power division circuit, and a power supply filtering and control circuit; the two independent frequency conversion channels down-convert the received two 6-18GHz radio frequency signals to an intermediate frequency; the local oscillator source circuit is used to generate the local oscillator signal required by the frequency conversion channel, and filter and appropriately amplify the local oscillator signal; the local oscillator power division circuit is used to power divide the local oscillator signal generated by the local oscillator source circuit and send it to the two frequency conversion channels respectively; the power supply filtering and control circuit is used to stabilize the voltage of the input frequency conversion component to the voltage value required by the device, and perform filtering processing, and the control circuit decodes the input control signal and sends it to the frequency conversion channel and the local oscillator source circuit respectively, and then goes to step S2.

[0038] S2: According to the functional index requirements of the dual-channel frequency conversion component in the RF receiver, the dual-channel frequency conversion component is analyzed and a corresponding solution block diagram is developed, such as Figure 2 , go to step S3.

[0039] S3: According to the scheme block diagram in step S2, determine the assembly method of each part of the circuit and the packaging of the components used. The front frequency conversion circuit, local oscillator filtering and gain adjustment circuit, and local oscillator power division circuit use bare chips combined with micro-assembly technology, which can effectively reduce the area occupied by the entire module and improve the integration of the components.

[0040] The local oscillator core board uses the chip LMX2595 as the core device, and cooperates with the capacitors and resistors in 0402 package as the core circuit for generating the local oscillator source. The core circuit uses RO4350B with 6 metal layers as the carrier and is installed in the component by screws; the core board and the surrounding micro-assembly printed circuit board are overlapped with the surrounding circuit boards through omega lines.

[0041] The local oscillator core board uses LMX2595 to generate local oscillator signals. LMX2595 has the characteristics of low cost and small size. LMX2595 and peripheral circuits are assembled using a separate printed circuit board combined with SMT technology, and installed in the component by screws, which is convenient for the assembly and debugging of the entire component. The power supply filter and control circuit installed on the back of the component uses a low-profile surface-mount regulator, a microcontroller STM32 (MCU), a low-profile packaged serial-to-parallel chip, and a 0603 packaged capacitor and resistor combined with SMT technology, which can effectively control the thickness of the entire component, and then go to step S4.

[0042] S4: According to the assembly form and device packaging determined in S3, and according to the required size of the components, the front of the frequency conversion component is divided into several parts according to function, including the frequency conversion channel, the local oscillator core circuit, the local oscillator filter and gain adjustment circuit, and the local oscillator power division circuit, such as Figure 3 , as follows:

[0043] The front of the frequency conversion component is 2 independent frequency conversion channels, local oscillator core circuit, local oscillator filter and gain adjustment circuit. The frequency conversion channels are placed on both sides of the component, and the local oscillator core circuit, local oscillator filter and gain adjustment circuit are placed in the middle of the component. Placing the local oscillator related circuit in the middle of the component can avoid the local oscillator signal from crossing the frequency conversion link: the local oscillator signal is directly sent to the mixer of the frequency conversion channel after filtering, amplification and power division. The main function of the frequency conversion channel is to down-convert the input RF signal to the intermediate frequency, including RF devices such as amplifiers, filters, mixers, switch filters, etc. RF bare chips are selected as the main components in the frequency conversion channel link. By adopting micro-assembly technology, the area occupied by the circuit is reduced and the integration of the module is improved. Each frequency conversion channel is in a separate structural cavity, thereby reducing the interference of other circuits on this channel. The local oscillator core circuit uses a separate printed circuit board, and the local oscillator core board is installed inside the module by screw installation, which reduces the design difficulty, facilitates separate debugging, and is also conducive to replacement. The local oscillator filter and gain adjustment circuit use bare chips combined with micro-assembly assembly technology, which is conducive to improving the integration of the module. The local oscillator core board is placed in the middle of the two frequency conversion channels. One end receives the 100MHz reference signal from the outside, and the other end outputs the local oscillator signal. It is connected to the surrounding micro-assembly process printed circuit board through the omega line. The local oscillator signal output by the local oscillator filter and gain adjustment circuit is respectively input into the frequency conversion channels on both sides of the component to participate in the frequency conversion. The back of the frequency conversion component is provided with a power supply filter circuit and a control circuit. The surface devices of the control board are soldered on the multi-layer control board through SMT. The control board is installed on the back of the component by screws. The power supply filter circuit steps down and filters the input power supply signal to generate the +5V power supply required by the RF device and the +3.3V power supply required by the local oscillator source related circuit. The control circuit includes the RF channel control circuit and the local oscillator source related control circuit. The control signal of the input component adopts the SPI serial code form, and two sets of control signals are used to control the frequency conversion channel and the local oscillator source respectively, reducing the mutual interference between the local oscillator frequency conversion channel control signal and the local oscillator control signal. The frequency conversion channel control signal is converted into a parallel code signal after passing through the serial-to-parallel chip to control the RF devices such as the digital control attenuator and the switch filter group in the frequency conversion channel. The signal controlling the local oscillator source is decoded by the STM32 microcontroller (MCU) to generate the control signal of LMX2595 and a set of serial codes. The serial codes are converted into a set of control signals through the serial-to-parallel chip to control the switch filter group and digitally controlled attenuator in the local oscillator filter and gain control circuit, such as Figure 4 shown.

[0044] The local oscillator filtering and gain adjustment circuit and the local oscillator power division circuit are assembled by using bare chips combined with micro-assembly technology and are placed between the local oscillator core board and the frequency conversion channel.

[0045] The STM32 microcontroller (MCU) that controls the local oscillator source is placed on the control board on the back of the component and integrated with the frequency conversion channel control circuit. The SPI serial code is used to control the local oscillator source and the frequency conversion channel. To prevent mutual interference between the control signal of the frequency conversion channel and the control signal of the local oscillator source, the entire component contains two sets of control codes, one for controlling the local oscillator source circuit and the other for controlling the frequency conversion channel.

[0046] After the serial code signal that controls the local oscillator source passes through the MCU, a set of control signals is generated to control the LMX2595, and at the same time a set of serial code control signals is generated. After the serial-to-parallel chip conversion, the serial code control signal is used to control the local oscillator filter and gain control circuit.

[0047] Go to step S5.

[0048] S5: According to the schematic diagram, calculate the height of the structural parts, printed circuit boards, and devices that make up each part of the circuit of the component. The circuit using the micro-assembly process includes 2 independent frequency conversion channels, local oscillator filtering and gain adjustment circuits, and local oscillator power division circuits. The overall thickness of the frequency conversion component is controlled at 10mm. The micro-assembly process is used on the front. The thickness of the outermost sealing cover plate is 0.8mm, the inner screw cover plate is 0.8mm, the thickness of the front microwave cavity is 3.2mm, and the front microwave circuit uses a 0.254mm thick RO5880 double-sided printed circuit board. With the bottom solder, the total thickness is about 0.3mm. The front microwave board is hollowed out for the chip placement part, and the height of the bare chip used is 0.1mm. Combined with the gasket at the bottom of the chip (thickness is 0.1mm), the total thickness is 0.2mm. The local oscillator core board installed in the front cavity of the component is fixed by screws. The local oscillator core board multilayer board uses a 6-layer FR4 printed board with a thickness of 1mm. The core component of the board is LMX2595, with a height of 1mm. The corresponding peripheral circuits around it use capacitors and resistors in 0402 packages, with a height of less than 1mm. In order to reduce the height difference between the local oscillator core board and the microwave double-sided board connected to it, the cavity part where the local oscillator core board is installed needs to be sunken 0.4mm to ensure that the height difference between the circuit on the upper part of the core board and the surrounding printed circuit boards using micro-assembly technology is within 0.3mm. The back cavity thickness of the frequency conversion component is 3.1mm. A 4-layer printed circuit board with a thickness of 0.8mm and a material of FR4 is selected as the control board. The devices on the control board are no higher than 2mm. Go to step S6.

[0049] S6: Draw the corresponding PCB layout according to the links, devices and circuit areas determined in S4 and S5, and proceed to step S7.

[0050] S7: Based on the device height determined by S5, the circuit functional area determined by S5 and S6, and the layout design, determine the cavity height distribution of the component, and design the structure, as follows:

[0051] Utilize the structural space between the two channels on the front of the frequency conversion component and dig out a cavity to place the local oscillator core board. Since the thickness of the local oscillator core board printed circuit is 1mm, in order to ensure that the height of the microstrip line on the printed circuit board and the microstrip line of the connected micro-assembly circuit is as small as possible, and at the same time ensure the thickness of the structural parts at this location, the lower ground of the cavity in this area is designed to be 0.4mm lower than the cavity of the micro-assembly circuit part. The local oscillator source-related circuits are placed separately in a cavity, and the local oscillator core board and the frequency conversion channels on both sides are isolated by structural parts to prevent the local oscillator signal from entering the frequency conversion link and causing interference. The two frequency conversion channels in the frequency conversion component are divided into separate cavities by structural parts. The back control board is assembled in the cavity on the back of the component with screws, and the control circuit is interconnected with the front micro-assembly circuit through a glass insulator, and then proceeds to step S8.

[0052] S8: Process and manufacture the frequency conversion components according to the designed printed circuit board drawing and structural diagram.

Claims

1. A design method for a low-cost dual-channel frequency conversion component with its own local oscillator source, characterized in that: Here are the steps: S1: According to the size and function requirements of the dual-channel frequency conversion component in the RF receiver, combined with the component budget, the functional circuits that the dual-channel frequency conversion component with its own local oscillator source needs to include are formulated as follows: Since the dual-channel frequency conversion component with its own local oscillator source is limited to a size of 103×87×10mm 3 The box structure is designed with a local oscillator source dual-channel frequency conversion component, which includes two independent frequency conversion channels, a local oscillator source circuit, a local oscillator power division circuit, and a power supply filter and control circuit; the two independent frequency conversion channels down-convert the received two 6-18GHz RF signals to intermediate frequencies; the local oscillator source circuit is used to generate the local oscillator signal required by the frequency conversion channel, and filter and amplify the local oscillator signal; The local oscillator power division circuit is used to divide the local oscillator signal generated by the local oscillator source circuit and send it to two frequency conversion channels respectively; The power supply filtering and control circuit is used to stabilize the voltage of the input frequency conversion component to the voltage value required by the device and perform filtering processing. The control circuit decodes the input control signal and sends it to the frequency conversion channel and the local oscillator source circuit respectively, and then proceeds to step S2; S2: According to the functional index requirements of the dual-channel frequency conversion component in the radio frequency receiver, the dual-channel frequency conversion component is analyzed and a corresponding solution block diagram is formulated, and then the process goes to step S3; S3: According to the scheme block diagram in step S2, determine the assembly method of each part of the circuit and the packaging of the components used; the frequency conversion circuit on the front of the component, the local oscillator filter and gain adjustment circuit, and the local oscillator power division circuit use bare chips combined with micro-assembly technology; the local oscillator core board uses LMX2595 to generate the local oscillator signal, and the LMX2595 and the peripheral circuit are assembled using a separate printed circuit board combined with the SMT process and installed in the component by screws; the power supply filter and control circuit uses a low-profile surface-mount regulator, an STM32 microcontroller, a low-profile packaged serial-to-parallel chip, and a 0603 packaged capacitor and resistor combined with the SMT process, and then proceed to step S4; S4: According to the assembly form and device packaging determined in S3, and according to the required size of the components, the front side of the frequency conversion component is divided into a frequency conversion channel, a local oscillator core circuit, a local oscillator filter and gain adjustment circuit, and a local oscillator power division circuit according to function, and then the process goes to step S5; S5: According to the schematic diagram, calculate the height of the structural parts, printed boards, and devices that make up each part of the circuit of the component; determine that the front micro-assembly circuit part uses a RO5880 double-sided printed board with a thickness of 0.254mm, and the front of the frequency conversion component contains 2 independent frequency conversion channels, a local oscillator filter and gain adjustment circuit, and a local oscillator power division circuit; the front of the frequency conversion component also contains a local oscillator core board, the thickness of the core board is 1mm, the maximum height of the device on it is 1mm, and the structural parts of the core board part are 0.4mm lower than the micro-assembly part circuit; the thickness of the back cavity of the component is 3.1mm, and the back uses a 4-layer printed board with a thickness of 0.8mm and a material of FR4; transfer to step S6; S6: Draw the corresponding PCB layout according to the links, devices and circuit areas determined in S4 and S5, and proceed to step S7; S7: According to the device height determined in S5, the circuit functional area determined in S5 and S6, and the layout design, the cavity height distribution of the component is determined, and the structure is designed, and then the process goes to step S8; S8: Process and manufacture the frequency conversion components according to the designed printed circuit board drawing and structural diagram.

2. The design method of a low-cost dual-channel frequency conversion component with its own local oscillator source according to claim 1 is characterized in that: In S3, according to the scheme block diagram, the low-cost LMX2595 chip is selected as the core device for generating the local oscillator source, and a separate multilayer board is used to make the local oscillator core board, as follows: The local oscillator core board uses the chip LMX2595 as the core device, and cooperates with the capacitors and resistors in 0402 package as the core circuit for generating the local oscillator source. The core circuit uses RO4350B with 6 metal layers as the carrier and is installed in the component by screws; the core board and the surrounding micro-assembly printed circuit board are overlapped with the surrounding circuit boards through omega lines.

3. The design method of a low-cost dual-channel frequency conversion component with its own local oscillator source according to claim 2 is characterized in that: In S4, according to the assembly form and device packaging determined in S3, and according to the required size of the components, the front side of the frequency conversion component is divided into a frequency conversion channel, a local oscillator core circuit, a local oscillator filter and gain adjustment circuit, and a local oscillator power division circuit according to function, as follows: The front of the frequency conversion component is 2 independent frequency conversion channels, local oscillator core circuit, local oscillator filtering and gain adjustment circuit; the main function of the frequency conversion channel is to down-convert the input RF signal to the intermediate frequency, including amplifiers, filters, mixers, switch filters, and RF bare chips are selected as the main components in the frequency conversion channel link. By adopting the micro-assembly process, the area occupied by the circuit is reduced and the integration of the module is improved; each frequency conversion channel is in a separate structural cavity, thereby reducing the interference of other circuits on this channel; the local oscillator core circuit uses a separate printed circuit board, and the local oscillator core board is installed inside the module by screw installation, which is convenient for separate debugging and replacement; the local oscillator filtering and gain adjustment circuits use bare chips combined with micro-assembly assembly technology, which is conducive to improving the integration of the module; the local oscillator core board is placed in the middle of the two frequency conversion channels, one end receives the 100MHz reference signal from the outside, and the other end outputs the local oscillator signal, which is connected to the surrounding micro-assembly process printed circuit boards through the omega line; The local oscillator signals output by the local oscillator filter and gain adjustment circuits are respectively input into the frequency conversion channels on both sides of the component to participate in the frequency conversion; a power supply filter circuit and a control circuit are arranged on the back of the frequency conversion component; the devices on the surface of the control board are welded on the multi-layer control board by SMT; the control board is mounted on the back of the component by screws; the power supply filter circuit steps down and filters the input power supply signal to generate a +5V power supply required by the radio frequency device and a +3.3V power supply required by the local oscillator source related circuit; the control circuit includes a radio frequency channel control circuit and a local oscillator source related control circuit; the control signal of the input component adopts the SPI serial code form, and two groups of control signals are used to control the frequency conversion channel and the local oscillator source respectively; the frequency conversion channel control signal is converted into a parallel code signal after passing through the serial-to-parallel chip to control the digitally controlled attenuator, switch filter group and other radio frequency devices in the frequency conversion channel; the signal controlling the local oscillator source is decoded by the STM32 microcontroller to generate the control signal of LMX2595 and a group of serial codes, and the serial code generates a group of control signals through the serial-to-parallel chip to control the switch filter group and the digitally controlled attenuator in the local oscillator filter and gain control circuit.

4. The design method of a low-cost dual-channel frequency conversion component with its own local oscillator source according to claim 3 is characterized in that: In S4, the local oscillator filtering and gain adjustment circuit and the local oscillator power division circuit are assembled using bare chips combined with micro-assembly technology and placed between the local oscillator core board and the frequency conversion channel.

5. The L-band local oscillator integrated multi-channel miniaturized frequency conversion component design method according to claim 4, characterized in that: In S4, the STM32 microcontroller that controls the local oscillator source is placed on the control board on the back of the component and integrated with the frequency conversion channel control circuit; the SPI serial code is used to control the local oscillator source and the frequency conversion channel. To prevent the control signal of the frequency conversion channel from interfering with the control signal of the local oscillator source, the entire component contains two sets of control codes, one for controlling the local oscillator source circuit and the other for controlling the frequency conversion channel.

6. The L-band local oscillator integrated multi-channel miniaturized frequency conversion component design method according to claim 5, characterized in that: In S4, the serial code signal controlling the local oscillator source generates a set of control signals for controlling LMX2595 after passing through the MCU, and also generates a set of serial code control signals, which are used to control the local oscillator filter and gain control circuit after serial-to-parallel chip conversion.

7. The design method of a low-cost dual-channel frequency conversion component with its own local oscillator source according to claim 6 is characterized in that: In S5, the height of the circuit structure parts, printed circuit boards, and devices of each part of the frequency conversion component is calculated as follows: the circuit using the micro-assembly process includes 2 independent frequency conversion channels, local oscillator filtering and gain adjustment circuits, and local oscillator power division circuits; the front of the frequency conversion component uses the micro-assembly process, the thickness of the outermost sealing cover plate is 0.8mm, the inner screw cover plate is 0.8mm, the thickness of the front microwave cavity is 3.2mm, and the front microwave circuit uses a RO5880 double-sided printed circuit board with a thickness of 0.254mm, plus the bottom solder, the total thickness is about 0.3mm; the chip placement part of the front microwave board is hollowed out, the height of the bare chip used is 0.1mm, combined with the gasket at the bottom of the chip, the thickness is 0.1mm, and the total thickness is 0.2mm; installation The local oscillator core board in the front cavity of the component is fixed by screws; the local oscillator core board multilayer board uses a 6-layer FR4 printed circuit board with a thickness of 1mm; the core component of the board is LMX2595, with a height of 1mm, and the corresponding peripheral circuits around it use 0402 packaged capacitors and resistors with a height of less than 1mm; in order to reduce the height difference between the local oscillator core board and the microwave double-sided board connected to it, the cavity part where the local oscillator core board is installed needs to be sunken 0.4mm to ensure that the height difference between the circuit on the upper part of the core board and the surrounding printed circuit boards using micro-assembly technology is within 0.3mm; the back cavity thickness of the frequency conversion component is 3.1mm, and a 4-layer printed circuit board with a thickness of 0.8mm and a material of FR4 is selected as the control board, and the devices on the control board are no higher than 2mm.

8. The design method of a low-cost dual-channel frequency conversion component with its own local oscillator source according to claim 6 is characterized in that: In S7, according to the device height determined in S5, the circuit functional area determined in S5 and S6, and the layout design, the cavity height distribution of the component is determined, and the structure is designed, as follows: The local oscillator core board is placed in a cavity by digging out a cavity in the structural space between the two channels on the front of the frequency conversion component. This area is 0.4mm lower than the cavity of the micro-assembly circuit part. The local oscillator core board is isolated from the frequency conversion channels on both sides by structural parts, and the local oscillator source-related circuits are placed separately in a cavity. The two frequency conversion channels in the frequency conversion component are divided into separate cavities by structural parts. The back control board is assembled in the cavity on the back of the component with screws, and the control circuit is interconnected with the front micro-assembly circuit through a glass insulator.

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