Hundred-time-frequency ultra-wideband frequency conversion circuit, structure and miniaturization design method thereof

Abstract

The invention provides a hundred-time frequency range ultra-wideband frequency conversion circuit, a hundred-time frequency range ultra-wideband frequency conversion structure and a miniaturization design method of the hundred-time frequency range ultra-wideband frequency conversion circuit. The hundred-time frequency range ultra-wideband frequency conversion circuit comprises an amplitude limiting amplification circuit, the frequency division preselection filtering module is used for carrying out segmented filtering on the ultra wide band radio frequency signal so as to reduce the influence of a harmonic signal and an out-of-band spurious signal on the circuit; the multi-stage frequency mixing module is used for mixing frequency; the local oscillation module is used for driving the multi-stage frequency mixing link to perform frequency conversion; the ultra-wideband frequency conversion circuit realizes ultra-wideband frequency conversion. The invention further designs a frequency conversion structure based on the circuit, the structure adopts a ceramic three-dimensional stacked structure design, grooves are formed in corresponding ceramic tube shells, the corresponding circuits are arranged in the corresponding grooves or formed cavities, and the circuits are isolated through a sealing process; the problem of low integration level of a circuit system in the prior art is solved through the frequency conversion structure.

Description

Technical Field

[0001] This invention relates to the field of microwave integrated circuit technology, and in particular to a 100-octave ultra-wideband frequency conversion circuit, its structure, and its miniaturization design method. Background Technology

[0002] With the continuous development of electronic technology, the demand for higher data transmission rates and data transmission is constantly increasing, which requires radio frequency technology to develop towards higher frequency bands and wider bandwidths. The rapid development of portable consumer electronics products and technologies such as aerospace and military electronics requires semiconductor devices to achieve miniaturization, lightweighting, high density, and reliability to the greatest extent possible, while the process nodes of integrated circuit technology are approaching their physical limits.

[0003] Currently, existing technologies typically use discrete electronic components to implement radio frequency circuit systems. These components are large in size, making it difficult to integrate multiple multi-channel and multi-frequency radio frequency channels. Furthermore, the operating bandwidth and frequency are limited, making it difficult to achieve reconfigurable design of the operating frequency, bandwidth, and output power characteristics of a general-purpose radio frequency circuit system. At the same time, the traditional two-dimensional planar design connection method results in low system integration and large component size, which cannot meet the requirements for the spacing between phased array antenna elements. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, this invention provides a 100-octave ultra-wideband frequency converter circuit, its structure and miniaturization design method, so as to achieve ultra-wideband, miniaturization and integration of the frequency converter circuit.

[0005] To achieve the above objectives, the present invention provides a 100-octave ultra-wideband frequency converter circuit, comprising:

[0006] A limiting amplifier circuit is used to limit the power of the input signal;

[0007] The frequency division pre-selection filter module is connected to the output of the limiting amplifier circuit. It includes: a first pre-selection filter circuit and a second pre-selection filter circuit. The first pre-selection filter circuit and the second pre-selection filter circuit filter the corresponding frequency band signal based on the input signal.

[0008] A multi-stage mixer module is connected to the output of the second pre-selection filter circuit. The input frequency is mixed stage by stage in the multi-stage mixer module and the output mixed signal is then used. Based on the output mixed signal and the filtered signal of the first pre-selection filter circuit, the final output frequency is selected by an RF switch.

[0009] The local oscillator module connects to the multi-stage mixer module to provide the local oscillator signal for each stage of the mixer link.

[0010] Preferably, the limiting amplifier circuit includes, in sequence: a limiter, a first shunt switch, a signal processing link, a mixing switch, and a second shunt switch; the signal processing link includes: a first amplitude amplifier link, a bypass link, and a second amplitude amplifier link; the signal frequency range limited by the first amplitude amplifier link is 300MHz to 18GHz, and the signal frequency range limited by the second amplitude amplifier link is 18GHz to 40GHz.

[0011] Preferably, the first pre-selection filtering circuit includes a first filtering link, and the second pre-selection filtering circuit includes a second filtering link and a third filtering link; the filtering frequency range of the first filtering link is 300MHz to 3GHz; the filtering frequency range of the second filtering link is 3GHz to 18GHz; the filtering frequency range of the third filtering link is 18GHz to 40GHz; each filtering link includes a filtering shunt switch, multiple filtering links of different frequency bands, and a filtering mixing switch; the input signal of different frequency bands is output to the subsequent link after selecting the corresponding filtering shunt switch, filtering link, and filtering mixing switch.

[0012] Preferably, the multi-stage mixer module includes three cascaded mixer links, each of which includes a mixer amplifier, a mixer, and a filter connected in sequence; the first-stage mixer link is connected to the output of the third filter link, and the output frequency of the first-stage mixer link and the filter frequency of the second filter link are selected by an RF switch to enter the input of the subsequent mixer link; the local oscillator module includes multiple local oscillator signal processing links, which are respectively connected to the mixer of each mixer link.

[0013] Preferably, in the multi-stage mixing module, the output of the third-stage mixing link is further connected in series with an intermediate frequency amplifier and a bandpass filter. The output signal of the third-stage mixing link is amplified by the intermediate frequency amplifier and filtered by the bandpass filter to output the intermediate frequency. The frequency range after mixing by the first-stage mixing link is 10.5GHz to 11.5GHz, and its corresponding output frequency of the local oscillator signal processing link is 14GHz to 36GHz. The frequency range after mixing by the second mixing link is 21GHz to 22GHz, and its corresponding output frequency of the local oscillator signal processing link is 24GHz to 40GHz. The frequency range after mixing by the third mixing link is 140MHz, and its corresponding output frequency of the local oscillator signal processing link is 21.14GHz to 22.14GHz.

[0014] The present invention also provides a frequency conversion structure for supporting a 100-octave ultra-wideband frequency conversion circuit, comprising:

[0015] The radio frequency structure includes: a first Kovar enclosure, a first ceramic housing, and a second ceramic housing stacked sequentially; an isolated filter slot and a mixer slot are provided between the first ceramic housing and the second ceramic housing; and a power supply slot is also provided on the second ceramic housing.

[0016] Preferably, the first Kovar enclosure and the first ceramic tube shell together form an isolated first chamber and a second chamber. The first chamber is used to house the limiting amplifier circuit, and the second chamber is used to house the third filter link and the first stage mixer link. The Kovar enclosure, filter slot, mixer slot and power supply slot are respectively provided with metal cover plates.

[0017] The filter slot includes a first filter slot and a second filter slot, which are disposed on the first ceramic tube shell. The first filter slot is used to place the first filter link, and the second filter link is used to place the second filter link.

[0018] The mixer slot includes a first mixer slot and a second mixer slot, which are disposed on the second ceramic tube shell. The first mixer slot is used to place the third-stage mixer link, and the second mixer slot is used to place the second-stage mixer link. The power supply slot is used to place the power supply module.

[0019] Preferably, the frequency conversion structure further includes multiple local oscillator structures, which are connected to the radio frequency structure. The local oscillator structure includes: a second Kovar enclosure and a third ceramic tube shell stacked in sequence. The local oscillator signal processing link is located in the third cavity formed by the second Kovar enclosure and the third ceramic tube shell. The bottom of the third ceramic tube shell is provided with a power supply slot for placing a power supply.

[0020] Preferably, the first ceramic shell has 16 layers, the second ceramic shell has 21 layers, and the third ceramic shell has 14 layers.

[0021] This invention also provides a design method for miniaturizing a frequency converter structure, which includes the following steps:

[0022] S1: Design of RF structure:

[0023] The first Kovar enclosure, the first ceramic housing, and the second ceramic housing are welded together. The limiting amplifier circuit is embedded in the first chamber, and the third filter link and the first-stage mixer link are embedded in the second chamber, sealed by parallel seam welding. The first filter link is embedded in the first filter slot, and the second filter link is embedded in the second filter slot, sealed by gold-tin sealing. The second-stage mixer link is embedded in the second mixer slot, and the third-stage mixer link is embedded in the first mixer slot, sealed by gold-tin sealing. The power management module is embedded in the power slot and sealed by gold-tin sealing. BGA solder balls are placed at the bottom of the second ceramic housing for signal input and output.

[0024] S2: Interconnection between radio frequency signals and power supply control signals on the same ceramic tube shell is achieved through surface metal microstrip lines, gold wire bonding, radio frequency vias penetrating the ceramic tube shell, and inner metal strip lines.

[0025] S3: Design multiple local oscillator structures:

[0026] The second Kovar enclosure and the third ceramic tube shell are welded together, and the local oscillator signal processing link is embedded in the third chamber and sealed by parallel seam welding; the power module is embedded in the corresponding power slot of the third ceramic tube shell and sealed by gold-tin fusion sealing.

[0027] S4: BGA solder balls are placed at the bottom of the second ceramic housing and the bottom of the third ceramic housing as signal inputs and outputs, and are connected to each other.

[0028] The present invention provides a 100-octave ultra-wideband frequency converter circuit, its structure, and its miniaturization design method. Compared with the prior art, its advantages are as follows:

[0029] For the frequency conversion circuit: A limiting amplifier circuit can restrict high-power signals from entering the RF link, preventing RF link saturation or chip damage. The input ultra-wideband RF signal, after passing through the limiting amplifier circuit, undergoes segmented filtering via a frequency division pre-selection filter module, thereby reducing the impact of harmonic signals and out-of-band spurious signals on the circuit. Based on the output frequency of each filtering segment of the frequency division pre-selection filter module, a multi-stage mixing module performs step-by-step mixing, converting the input frequency to a frequency that the AD can sample, thus achieving a 100-octave ultra-wideband frequency conversion. Each mixing stage is connected to a local oscillator signal processing link, which provides the mixer with a suitable power local oscillator signal to drive the mixer to operate normally and output the mixed signal. This circuit, through multi-segment pre-selection filtering and multi-stage mixing to adapt to ultra-wideband signal frequency conversion, achieves reconfigurable characteristics of the RF circuit system, including operating frequency, bandwidth, and output power.

[0030] For the frequency conversion structure: the structure adopts a three-dimensional ceramic stacked structure design, and grooves are dug on the corresponding ceramic tube shells to set the corresponding circuits in the corresponding grooves or the formed cavities. The circuits are isolated by the sealing process. The present invention solves the problem of low integration of existing circuit systems by using the frequency conversion structure, and realizes the integrated and miniaturized design of ultra-wideband frequency conversion circuits. Attached Figure Description

[0031] Figure 1 A simplified block diagram of the 100-octave ultra-wideband frequency converter circuit provided by the present invention;

[0032] Figure 2 A schematic diagram of the limiting amplifier circuit provided by the present invention;

[0033] Figure 3This is a schematic diagram of the structure of the frequency division pre-selection filter module provided by the present invention;

[0034] Figure 4 A schematic block diagram of the 100-octave ultra-wideband frequency converter circuit provided by the present invention;

[0035] Figure 5 This is a schematic diagram of the 300MHz to 3GHz segment of the first filtering link in this invention;

[0036] Figure 6 This is a schematic diagram of the 3GHz to 18GHz segment of the second filtering link in this invention;

[0037] Figure 7 This is a schematic diagram of the 18GHz to 40GHz segment of the third filtering link in this invention;

[0038] Figure 8 This is a circuit block diagram of the first mixing local oscillator signal of the present invention, ranging from 14GHz to 36GHz;

[0039] Figure 9 This is a circuit block diagram of the second mixing local oscillator signal of the present invention, ranging from 24GHz to 40GHz.

[0040] Figure 10 This is a circuit block diagram of the third mixing local oscillator signal of the present invention, ranging from 21.14 GHz to 22.14 GHz.

[0041] Figure 11 A three-dimensional stacked cross-sectional view of the radio frequency structure in the frequency conversion structure provided by the present invention;

[0042] Figure 12 A three-dimensional stacked cross-sectional view of the local oscillator structure in the frequency conversion structure provided by the present invention;

[0043] Figure 13 This is a cross-sectional view of the overall three-dimensional stacked structure of the frequency conversion structure of the present invention.

[0044] The diagram is labeled as follows: 1-First chamber; 2-Second chamber; 3-Metal cover plate; 4-1-First Kovar enclosure; 4-2-Second Kovar enclosure; 5-RF via; 6-First ceramic housing; 7-Second filter slot; 8-Grounding via; 9-Second mixer slot; 10-BGA solder ball; 11-Second ceramic housing; 12-First filter slot; 13-First mixer slot; 14-Power supply slot; 15-Third chamber; 16-Third ceramic housing. Detailed Implementation

[0045] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0046] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0047] In this embodiment of the invention, all directional indicators (such as up, down, left, right, front, back, lateral, longitudinal, etc.) are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indicator will also change accordingly.

[0048] Due to installation errors and other reasons, the parallel relationship referred to in the embodiments of the present invention may actually be an approximate parallel relationship, and the perpendicular relationship may actually be an approximate perpendicular relationship.

[0049] like Figure 1 As shown, this invention provides a 100-octave ultra-wideband frequency conversion circuit, comprising: a limiting amplifier circuit, a frequency division pre-selection filter module, a multi-stage mixer module, and a local oscillator module. The limiting amplifier circuit limits the power of the input signal. The frequency division pre-selection filter module, connected to the output of the limiting amplifier circuit, includes: a first pre-selection filter circuit and a second pre-selection filter circuit, which filter the corresponding frequency band signal based on the input signal. The multi-stage mixer module, connected to the output of the second pre-selection filter circuit, outputs a mixed signal after the input frequency is mixed stage by stage in the multi-stage mixer module; based on the output mixed signal and the filtered signal of the first pre-selection filter circuit, the final output frequency is selected by an RF switch. The local oscillator module, connected to the multi-stage mixer module, provides a local oscillator signal for each stage of the mixer link.

[0050] Specifically, this invention limits high-power signals from entering the RF link by setting a limiting amplifier circuit, preventing RF link saturation or chip damage. After passing through the limiting amplifier circuit, the input ultra-wideband RF signal is segmented and filtered by a frequency division pre-selection filter module, thereby reducing the impact of harmonic signals and out-of-band spurious signals on the circuit. Based on the output frequency of each filtering link of the frequency division pre-selection filter module, a multi-stage mixing module is used for step-by-step mixing, converting the input frequency to a frequency that the AD can sample, thus achieving a 100-octave ultra-wideband frequency conversion. Each mixing link is connected to a local oscillator signal processing link, which provides a local oscillator signal of appropriate power to drive the mixing link to work normally and output the mixed signal. Preferably, the mixing link is a mixer.

[0051] The invention also includes a power supply module that can individually control the power supply to different links, thereby preventing signal crosstalk.

[0052] like Figure 2 As shown, the limiting amplifier circuit includes, in sequence: a limiter, a first shunt switch, a signal processing link, a mixing switch, and a second shunt switch. The signal processing link includes: a first amplitude amplifier link, a bypass link, and a second amplitude amplifier link. The first amplitude amplifier link limits the signal frequency range to 300MHz–18GHz, and the second amplitude amplifier link limits the signal frequency range to 18GHz–40GHz. By limiting the level of high-power signals in the 300MHz–40GHz range, the limiting amplifier circuit prevents high-power signals from entering subsequent links, thus preventing circuit saturation or even damage. Simultaneously, it amplifies the 300MHz–40GHz frequency signals in segments, and the link is designed with a bypass function. When the link gain is too high, it can be reduced by bypassing the amplifier; or during testing, if the output signal is found to be low, the bypass link can be used to check for a faulty amplification link, effectively improving signal amplitude adjustment and circuit debugging.

[0053] In this embodiment, the first pre-selection filtering circuit includes a first filtering link, and the second pre-selection filtering circuit includes a second filtering link and a third filtering link; the filtering frequency range of the first filtering link is 300MHz to 3GHz; the filtering frequency range of the second filtering link is 3GHz to 18GHz; and the filtering frequency range of the third filtering link is 18GHz to 40GHz. Figure 3 As shown, each filtering link includes: a filtering shunt switch, multiple filtering links of different frequency bands, and a filtering mixing switch; the input signals of different frequency bands are output to the subsequent links after selecting the corresponding filtering shunt switch, filtering link, and filtering mixing switch.

[0054] Both the first and second pre-selection filter circuits can be configured with multiple filter links according to the actual application scenario. In this embodiment, it is preferable that the first pre-selection filter circuit has one filter link, namely the first filter link, and the second pre-selection filter circuit has two filter links, namely the second filter link and the third filter link. Figure 4 The corresponding frequency ranges of the links, from top to bottom, are: 300MHz~3GHz, 3GHz~18GHz, and 18GHz~40GHz. Through continuous refinement of the three-segment filtering, filtering of the 300MHz~40GHz broadband signal is achieved, avoiding the impact of signal harmonics, image frequencies, and other spurious signals on subsequent links.

[0055] like Figure 5 As shown, for the first filtering link, the frequency range of 300MHz to 3GHz is decomposed into five filtering loops with different frequencies, namely: 300MHz to 450MHz, 450MHz to 700MHz, 700MHz to 1100MHz, 1100MHz to 1800MHz and 1800MHz to 3000MHz.

[0056] like Figure 6 As shown, for the second filtering link, the filtering range of 3GHz to 18GHz is decomposed into four different frequency filtering loops, namely: 3GHz to 5GHz, 5GHz to 8GHz, 8GHz to 13GHz and 13GHz to 18GHz.

[0057] like Figure 7 As shown, for the third filtering link, the filtering range of 18GHz to 40GHz is decomposed into four different frequency filtering loops, namely: 18GHz to 23GHz, 23GHz to 25GHz, 25GHz to 34GHz and 34GHz to 40GHz.

[0058] In this embodiment, the multi-stage mixing module includes three cascaded mixing links. Each mixing link includes a mixing amplifier, a mixer, and a filter connected in sequence. The first-stage mixing link is connected to the output of the third filtering link. The output frequency of the first-stage mixing link and the filtering frequency of the second filtering link are selected by an RF switch and enter the input of the subsequent mixing link. The local oscillator module includes multiple local oscillator signal processing links, which are respectively connected to the mixer of each mixing link.

[0059] Specifically, the multi-stage mixing link uses a three-stage mixing design to mix 3–18 GHz RF signals to intermediate frequency signals. For the first-stage mixing link, the 18–40 GHz signal is mixed to the 10.5–11.5 GHz range. A mixer amplifier and filter are designed on the mixing link to adjust the signal amplitude and filter out out-of-band spurious signals introduced after mixing. Simultaneously, the image frequency of the input signal from the second mixing stage (i.e., the second-stage mixing link) is filtered to avoid affecting the link noise figure and spurious suppression of subsequent links. The corresponding output frequency of the local oscillator signal processing link is 14 GHz–36 GHz. For the second-stage mixing link, the signal entering the second-stage mixing link is selected by an RF switch and then mixed to the 21–22 GHz range. The mixing link also has a corresponding mixer amplifier and filter designed to adjust the signal amplitude and filter out out-of-band spurious signals introduced after mixing. The corresponding output frequency of the local oscillator signal processing link is 24 GHz–40 GHz. In each stage of the mixing link, the filter can be a low-pass filter or other types of filters.

[0060] In the multi-stage mixer module, the output of the third-stage mixer link is connected in series with an intermediate frequency amplifier and a bandpass filter. The output signal of the third-stage mixer link is amplified by the intermediate frequency amplifier and filtered by the bandpass filter to output the intermediate frequency.

[0061] Specifically, the third-stage mixing link is used to mix the 21-22 GHz signal to 140 MHz. The mixing link is designed with corresponding mixing amplifiers, mixers and low-pass filters. The low-pass filter is used to filter out spurious signals at the far end of the intermediate frequency signal, such as the radio frequency signal and its harmonics, the local oscillator signal and its harmonics, and spurious signals generated by intermodulation between the radio frequency signal and the local oscillator signal. The band-pass filter connected in series at the output of the third-stage mixing link is used to filter out spurious signals at the near end of the intermediate frequency signal.

[0062] The specific frequency selection and frequency conversion process are described below:

[0063] like Figure 4 As shown, for RF signals in the 300MHz to 3GHz range, no mixing is performed; only attenuation or amplification filtering is applied to meet the sampling requirements of the subsequent ADC. The appropriate filter is selected based on the frequency band of the input 300MHz to 3GHz signal via a filter switch. For example... Figure 5 As shown.

[0064] For 3–18 GHz radio frequency signals, the amplitude is first adjusted by a limiting amplifier circuit, and then the filter is selected by a filter switch according to the input signal frequency. Figure 6As shown, the radio frequency (RF) signal is filtered to remove harmonic signals, image signals, and other out-of-band spurious signals. Then, the RF signal is input to the second-stage mixing link in the multi-stage mixing module. By providing a local oscillator signal of 24–40 GHz, the 3–18 GHz RF signal is mixed to a 21–22 GHz intermediate frequency (IF) signal. The 21–22 GHz IF signal is then input to the third-stage mixing link in the multi-stage mixing module. By providing a local oscillator signal of 21.14–22.14 GHz, the 21–22 GHz IF signal is mixed to a 140 MHz IF signal. Finally, after filtering and amplification, the signal is output to the ADC sampling link.

[0065] For 18–40 GHz radio frequency signals, the amplitude is first adjusted by an amplification and limiting module, and then the filter is selected by a filter switch according to the input signal frequency. Figure 7 As shown, harmonic signals, image signals, and other out-of-band spurious signals of the radio frequency signal are filtered out by a filter, and then the radio frequency signal is input to the first-stage mixing link in the multi-stage mixing module; by providing a local oscillator signal of 14-36GHz, the 18-40GHz radio frequency signal is frequency-converted to 10.5-11.5GHz, and then the intermediate frequency signal of 10.5-11.5GHz is input to the second-stage mixing link and the third-stage mixing link shared with 3-18GHz.

[0066] like Figure 8 The diagram shown is a block diagram of the local oscillator module designed for the first-stage mixer link. It integrates a phase-locked loop (PLL1) chip to generate a 7–18 GHz signal, which is multiplied to produce a 14–36 GHz local oscillator signal. Segmented filtering is used to remove high-order harmonics and other out-of-band spurious signals from the multiplied signal. The segmented frequencies are 14–23 GHz, 23–29 GHz, 29–32 GHz, and 32–36 GHz. After filtering, the output local oscillator signal is amplified to meet the mixer's drive power requirements.

[0067] like Figure 9 The diagram shown is a block diagram of the local oscillator module designed for the second-stage mixer link. It integrates a phase-locked loop (PLL2) chip to generate a 12–20 GHz signal, which is then multiplied to produce a 24–40 GHz local oscillator signal. Segmented filtering removes high-order harmonics and other out-of-band spurious signals from the multiplied signal; the segmented frequencies are 24–28 GHz, 28–32 GHz, 32–36 GHz, and 36–40 GHz. After filtering, the output local oscillator signal is amplified to meet the mixer's drive power requirements.

[0068] Figure 10This is a block diagram of the local oscillator module designed for the third-stage mixer link. It integrates a phase-locked loop (PLL3) chip to generate a 10.57–11.07 GHz signal, which is multiplied to produce a 21.14–22.14 GHz local oscillator signal. A bandpass filter is used to filter out higher harmonics and other out-of-band spurious signals from the multiplied signal. After filtering, the output local oscillator signal is amplified to meet the mixer's drive power requirements.

[0069] like Figure 11 As shown, the present invention also provides a frequency conversion structure for carrying the above-mentioned 100-octave ultra-wideband frequency conversion circuit, which includes: a radio frequency structure, which includes: a first Kovar frame 4-1, a first ceramic tube shell 6 and a second ceramic tube shell 11 stacked in sequence; an isolated filter slot and a mixer slot are provided between the first ceramic tube shell 6 and the second ceramic tube shell 11; and a power supply slot 14 is also provided on the second ceramic tube shell 11.

[0070] Specifically, the frequency conversion structure of this invention uses a triple-stack design to support a 100-octave ultra-wideband frequency conversion circuit, thereby achieving the integrated and miniaturized design of the 100-octave ultra-wideband frequency conversion circuit. In the frequency conversion structure, by placing each independent filtering link and mixing link in corresponding slots or chambers, crosstalk between different signals through power supply or space is avoided.

[0071] In this embodiment, the first Kovar enclosure 4-1 and the first ceramic housing 6 together form an isolated first chamber 1 and a second chamber 2. The first chamber 1 is used to house the limiting amplifier circuit, and the second chamber 2 is used to house the third filter link and the first-stage mixer link. The first Kovar enclosure 4-1, the filter slot, the mixer slot, and the power supply slot 14 are respectively provided with metal cover plates 3. The filter slot includes a first filter slot 12 and a second filter slot 7, which are disposed on the first ceramic housing 6. The first filter slot 12 is used to house the first filter link, and the second filter slot 7 is used to house the second filter link. The mixer slot includes a first mixer slot 13 and a second mixer slot 9, which are disposed on the second ceramic housing 11. The first mixer slot 13 is used to house the third-stage mixer link, and the second mixer slot 9 is used to house the second-stage mixer link. The power supply slot 14 is used to house the power supply module.

[0072] In this invention, the first Kovar frame 4-1 and the first ceramic tube shell 6 are welded together at high temperature, forming a first chamber 1 with the metal cover on top of the first Kovar frame 4-1, which embeds a limiting amplifier circuit, and a second chamber 2 with an 18-40GHz filter link and a first-stage mixer link. The two chambers are airtight by parallel seam welding. The first ceramic tube shell 6 adopts a 16-layer single-sided cavity structure, that is, a first filter groove 12 and a second filter groove 7 are set on the contact surface between the first ceramic tube shell 6 and the second ceramic tube shell 11. The 300MHz-3GHz filter link is embedded in the first filter groove 12, and the 3-18GHz filter link is embedded in the second filter groove 7. The airtightness of the first filter groove 12 and the second filter groove 7 is achieved by gold-tin sealing.

[0073] The second ceramic housing 11 features a 21-layer double-sided cavity structure. Its top has a first mixer slot 13 and a second mixer slot 9 corresponding to the filter slots, while its bottom has a power supply slot 14 for housing the power module circuitry of the RF structure. The second-stage mixer link is embedded in the second mixer slot 9, and the third-stage mixer link is embedded in the first mixer slot 13. The first mixer slot 13 and the second mixer slot 9 are hermetically sealed using gold-tin bonding. The modules within the filter and mixer slots are connected to their corresponding ceramic housings via bonding wires. The circuits in the cavity and filter slots, and the circuits in the mixer slot and power supply slot 14, are electrically connected via grounding vias 8. Within each module, devices are connected via microstrip lines. The contact surfaces on both sides of the first ceramic housing 6 and the second ceramic housing 11 have RF vias 5 that pass through to the corresponding ceramic housing. The RF vias 5 corresponding to the two ceramic housings are connected via BGA solder balls 10 to achieve interconnection between the signal and power control circuits of the two different ceramic housings. For the stacked frequency converter structure, signal input and output are achieved by embedding BGA solder balls 10 at the bottom.

[0074] In this embodiment, each ceramic shell is made of alumina ceramic, and the thickness of each alumina ceramic substrate layer is 0.15 mm. The corresponding chambers on the first ceramic shell 6 and the third ceramic shell 16 are 1.7 mm deep and are airtight with the corresponding Kovar frame by parallel seam welding. The filter slot and mixer slot corresponding to the first ceramic shell 6 are 1.05 mm deep and are airtight by gold-tin sealing. The filter slot, mixer slot and power supply slot 14 corresponding to the second ceramic shell 11 are 1.05 mm deep and are airtight by gold-tin sealing. The slot on the third ceramic shell 16 used to place the power supply module is 1.05 mm deep and is airtight by gold-tin sealing.

[0075] In this invention, the frequency conversion structure also includes multiple local oscillator structures. The local oscillator structures are connected to the radio frequency structure. The local oscillator structure includes: a second Kovar enclosure 4-2 and a third ceramic tube shell 16 stacked in sequence. The local oscillator module is located in the third cavity formed by the second Kovar enclosure 4-2 and the third ceramic tube shell 16. The bottom of the third ceramic tube shell 16 is provided with a power supply slot 14 for placing a power supply.

[0076] Specifically, considering the crosstalk between different frequency signals that introduces spurious signals, each ceramic tube cavity is designed as an independent cavity, and each frequency source is designed in a separate ceramic tube. For example... Figure 12 The diagram shows a cross-sectional view of the independent ceramic housing of the local oscillator module. The third ceramic housing 16 is a 14-layer single-sided cavity structure (i.e., a power supply slot 14 structure). The second Kovar frame 4-2 and the third ceramic housing 16 are welded together at high temperature. The local oscillator RF signal link is embedded in the third chamber 15, and the third chamber 15 is hermetically sealed by parallel seam welding. The power management part of the local oscillator link is embedded in the power supply slot 14, and the power supply slot 14 is hermetically sealed by gold and solder. Signal input and output are achieved at the bottom of each frequency source ceramic housing by inserting BGA solder balls 10.

[0077] In this invention, the local oscillator module provides different local oscillator source signals according to the multi-stage mixing module. The different local oscillator signals are obtained through phase-locked loop and frequency multiplication. The wide local oscillator link is designed with a segmented filtering module to effectively suppress the mutual mixing between local oscillator harmonic signals and thus prevent spurious signals. At the same time, in order to ensure the spectral purity of the local oscillator source signal, each local oscillator module is designed with a separate power management chip, and each module is designed in an independent ceramic tube shell to avoid crosstalk between different local oscillator signals through power supply or space.

[0078] The chips embedded on the same ceramic substrate are arranged in a staggered manner, and their bottom is provided with heat dissipation holes to achieve grounding and heat dissipation.

[0079] Based on the above-described frequency converter structure, the present invention also provides a design method for miniaturizing the frequency converter structure, comprising the following steps:

[0080] S1: Design of RF structure:

[0081] The first Kovar enclosure 4-1, the first ceramic housing 6, and the second ceramic housing 11 are welded together. The limiting amplifier circuit is embedded in the first chamber 1, and the third filter link and the first-stage mixer link are embedded in the second chamber 2, and sealed by parallel seam welding. The first filter link is embedded in the first filter slot 12, and the second filter link is embedded in the second filter slot 7, and sealed by gold and solder sealing. The second-stage mixer link is embedded in the second mixer slot 9, and the third-stage mixer link is embedded in the first mixer slot 13, and sealed by gold and solder sealing. The power management module is embedded in the power slot 14 and sealed by gold and solder sealing. BGA solder balls 10 are set at the bottom of the second ceramic housing 11 as signal input and output.

[0082] S2: Interconnection between radio frequency signals and power supply control signals on the same ceramic tube shell is achieved through surface metal microstrip lines, gold wire bonding, radio frequency through-holes 5 penetrating the ceramic tube shell, and inner metal strip lines.

[0083] S3: Design multiple local oscillator structures:

[0084] The second Kovar frame 4-2 and the third ceramic tube shell 16 are welded together, and the local oscillator module is embedded in the third chamber 15 and sealed by parallel seam welding; the power module is embedded in the power slot 14 corresponding to the third ceramic tube shell 16 and sealed by gold-tin fusion sealing.

[0085] S4: BGA solder balls 10 are provided at the bottom of the second ceramic housing 11 and the bottom of the third ceramic housing 16 as signal input and output, and are connected to each other.

[0086] For the completed RF section ceramic housing and frequency source ceramic housing, to achieve the overall link function, the RF ceramic housing and the three frequency sources (i.e., the structure corresponding to the local oscillator module) are soldered onto the same ceramic substrate, and are independent of each other to avoid crosstalk between different local oscillator signals. For example... Figure 13 As shown. Simultaneously, the interconnection of signals and power supply control between the ceramic tube shells and the output of signals are realized through the surface metal microstrip lines, inner metal strip lines and radio frequency vias penetrating the substrate.

[0087] Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

Claims

1. A 100-octave ultra-wideband frequency converter circuit, characterized in that, include; A limiting amplifier circuit is used to limit the power of the input signal; The frequency division pre-selection filter module is connected to the output of the limiting amplifier circuit. It includes: a first pre-selection filter circuit and a second pre-selection filter circuit. The first pre-selection filter circuit and the second pre-selection filter circuit filter the corresponding frequency band signal based on the input signal. A multi-stage mixer module is connected to the output of the second pre-selection filter circuit. The input frequency is mixed stage by stage in the multi-stage mixer module and the output mixed signal is then used. Based on the output mixed signal and the filtered signal of the first pre-selection filter circuit, the final output frequency is selected by an RF switch. The local oscillator module connects to the multi-stage mixer module to provide the local oscillator signal for each stage of the mixer link.

2. The 100-octave ultra-wideband frequency converter circuit according to claim 1, characterized in that, The limiting amplifier circuit includes, in sequence: a limiter, a first shunt switch, a signal processing link, a mixing switch, and a second shunt switch; the signal processing link includes: a first amplitude amplifier link, a bypass link, and a second amplitude amplifier link; the signal frequency range limited by the first amplitude amplifier link is 300MHz to 18GHz, and the signal frequency range limited by the second amplitude amplifier link is 18GHz to 40GHz.

3. The 100-octave ultra-wideband frequency converter circuit according to claim 1, characterized in that, The first pre-selection filtering circuit includes a first filtering link, and the second pre-selection filtering circuit includes a second filtering link and a third filtering link; the filtering frequency range of the first filtering link is 300MHz to 3GHz; the filtering frequency range of the second filtering link is 3GHz to 18GHz; the filtering frequency range of the third filtering link is 18GHz to 40GHz; each filtering link includes a filtering shunt switch, multiple filtering links of different frequency bands, and a filtering mixing switch; the input signal of different frequency bands selects the corresponding filtering shunt switch, filtering link, and filtering mixing switch and then outputs it to the subsequent link.

4. The 100-octave ultra-wideband frequency converter circuit according to claim 1, characterized in that, The multi-stage mixing module includes three cascaded mixing links. Each mixing link includes a mixing amplifier, a mixer, and a filter connected in sequence. The first-stage mixing link is connected to the output of the third filtering link. The output frequency of the first-stage mixing link and the filtering frequency of the second filtering link are selected by an RF switch and enter the input of the subsequent mixing link. The local oscillator module includes multiple local oscillator signal processing links, which are respectively connected to the mixer of each mixing link.

5. The 100-octave ultra-wideband frequency converter circuit according to claim 4, characterized in that, In the multi-stage mixing module, the output of the third-stage mixing link is further connected in series with an intermediate frequency amplifier and a bandpass filter. The output signal of the third-stage mixing link is amplified by the intermediate frequency amplifier and filtered by the bandpass filter to output the intermediate frequency. The frequency range after mixing by the first-stage mixing link is 10.5GHz to 11.5GHz, and its corresponding output frequency of the local oscillator signal processing link is 14GHz to 36GHz. The frequency range after mixing by the second mixing link is 21GHz to 22GHz, and its corresponding output frequency of the local oscillator signal processing link is 24GHz to 40GHz. The frequency range after mixing by the third mixing link is 140MHz, and its corresponding output frequency of the local oscillator signal processing link is 21.14GHz to 22.14GHz.

6. A frequency conversion structure for carrying the 100-octave ultra-wideband frequency conversion circuit according to any one of claims 1 to 5, characterized in that, include: The radio frequency structure includes: a first Kovar enclosure, a first ceramic housing, and a second ceramic housing stacked sequentially. An isolation filter slot and a mixer slot are provided between the first ceramic tube shell and the second ceramic tube shell; a power supply slot is also provided on the second ceramic tube shell.

7. The 100-octave ultra-wideband frequency converter circuit structure according to claim 6, characterized in that, The first Kovar enclosure and the first ceramic tube shell together form an isolated first chamber and a second chamber. The first chamber is used to house the limiting amplifier circuit, and the second chamber is used to house the third filter link and the first stage mixer link. The Kovar enclosure, filter slot, mixer slot and power supply slot are respectively provided with metal cover plates. The filter slot includes a first filter slot and a second filter slot, which are disposed on the first ceramic tube shell. The first filter slot is used to place the first filter link, and the second filter link is used to place the second filter link. The mixing slot includes a first mixing slot and a second mixing slot, which are disposed on the second ceramic tube shell. The first mixing slot is used to place the third-stage mixing link, and the second mixing slot is used to place the second-stage mixing link. The power supply slot is used to place the power supply module.

8. The ultra-wideband frequency converter circuit structure according to claim 1, characterized in that, It also includes multiple local oscillator structures, which are connected to the radio frequency structure. The local oscillator structure includes: a second Kovar frame and a third ceramic tube shell stacked in sequence. The local oscillator signal processing link is located in the third cavity formed by the second Kovar frame and the third ceramic tube shell. The bottom of the third ceramic tube shell is provided with a power supply slot for placing the power supply.

9. The 100-octave ultra-wideband frequency converter circuit structure according to claim 7 or 8, characterized in that, The first ceramic tube shell has 16 layers, the second ceramic tube shell has 21 layers, and the third ceramic tube shell has 14 layers.

10. A design method for miniaturizing a frequency converter structure, characterized in that, Includes the following steps: S1: Design of RF structure: The first Kovar enclosure, the first ceramic housing, and the second ceramic housing are welded together. The limiting amplifier circuit is embedded in the first chamber, and the third filter link and the first-stage mixer link are embedded in the second chamber, sealed by parallel seam welding. The first filter link is embedded in the first filter slot, and the second filter link is embedded in the second filter slot, sealed by gold-tin sealing. The second-stage mixer link is embedded in the second mixer slot, and the third-stage mixer link is embedded in the first mixer slot, sealed by gold-tin sealing. The power management module is embedded in the power slot and sealed by gold-tin sealing. BGA solder balls are placed at the bottom of the second ceramic housing for signal input and output. S2: Interconnection between radio frequency signals and power supply control signals on the same ceramic tube shell is achieved through surface metal microstrip lines, gold wire bonding, radio frequency vias penetrating the ceramic tube shell, and inner metal strip lines. S3: Design multiple local oscillator structures: The second Kovar enclosure and the third ceramic tube shell are welded together, and the local oscillator signal processing link is embedded in the third chamber and sealed by parallel seam welding; the power module is embedded in the corresponding power slot of the third ceramic tube shell and sealed by gold-tin fusion sealing. S4: BGA solder balls are placed at the bottom of the second ceramic housing and the bottom of the third ceramic housing as signal inputs and outputs, and are connected to each other.

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