Dual-channel receiving frequency conversion SIP (session initiation protocol), receiving circuit and receiving method

Abstract

The invention discloses a dual-channel receiving frequency conversion SIP, the SIP comprises a packaging shell and an internal substrate assembly installed in the packaging shell, the internal substrate assembly comprises an upper substrate and a lower substrate, the upper substrate and the lower substrate are stacked together, a signal transmission medium is arranged between the upper substrate and the lower substrate, and the upper substrate and the lower substrate are stacked together. The upper layer substrate is provided with a local oscillator circuit, the lower layer substrate is provided with two receiving frequency conversion channel circuits, the local oscillator circuit is connected with the two receiving frequency conversion channel circuits, the lower layer substrate is connected with the packaging shell through gold wire bonding, and the packaging shell is fixedly connected with pins. The invention realizes a miniaturized, multifunctional and highly integrated dual-channel receiving frequency conversion SIP, has the functions of dual-channel receiving down-conversion, amplification, filtering and the like, and has a channel gain control function and a frequency conversion local oscillator signal generation function.

Description

Technical Field

[0001] The present invention relates to the technical field of diversity reception, and in particular to a dual-channel receiving frequency conversion SIP, a receiving circuit and a receiving method. Background Art

[0002] As modern wireless communication systems evolve toward multi-band and multi-standard designs, the demand for miniaturization and integration of receiver front-end modules is becoming increasingly urgent. In applications such as satellite communications, radar systems, and 5G base stations, traditional receiver channels built with discrete components suffer from large size, high power consumption, and poor consistency. System-in-Package (SIP) technology, by integrating multiple chips and passive components into a single package, has become an effective solution for miniaturizing the RF front end. Currently, the receiver frequency conversion module, as a core component of the RF front end, must simultaneously handle functions such as mixing, amplification, and filtering. Dual-channel receiver frequency conversion, due to its ability to support simultaneous processing of multiple channels, is widely used in critical military information equipment such as radar, communications, and electronic warfare.

[0003] Traditional RF receiving and frequency conversion circuits use a multi-chip assembly method, and each functional unit is connected by PCB traces, resulting in a large module size and difficulty meeting the high integration requirements of modern communication equipment. Existing SIP modules mostly use a planar layout design, and the parallel arrangement of dual-channel RF traces easily leads to signal crosstalk between channels. Local hotspots are generated when the power amplifier and mixer are integrated. Traditional structures mostly use epoxy resin packaging materials with low thermal conductivity, which causes device parameter drift and affects gain flatness. Summary of the Invention

[0004] To overcome or at least partially address the aforementioned issues, the present invention provides a dual-channel receive frequency conversion SIP, a receive circuit, and a receive method. The present invention implements a compact, multifunctional, and highly integrated dual-channel receive frequency conversion SIP, which features dual-channel receive down-conversion, amplification, filtering, channel gain control, and frequency conversion local oscillator signal generation.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A dual-channel receiving frequency conversion SIP, characterized in that: the SIP includes a packaging shell and an internal substrate assembly installed in the packaging shell, the internal substrate assembly includes an upper substrate and a lower substrate, the upper substrate and the lower substrate are stacked together, a signal transmission medium is provided between the upper substrate and the lower substrate, the upper substrate is provided with a local oscillator circuit, the lower substrate is provided with two receiving frequency conversion channel circuits, the local oscillator circuit is connected to the two receiving frequency conversion channel circuits, the lower substrate and the packaging shell are interconnected by gold wire bonding, and the packaging shell is fixedly connected with pins.

[0007] The packaging shell includes a customized tube shell and a cover plate. The customized tube shell includes a metal frame and a bottom substrate. The lower substrate and the bottom substrate are interconnected by gold wire bonding. The cover plate and the bottom substrate are respectively installed on the top and bottom of the metal frame to form a packaging cavity. The upper substrate and the lower substrate are stacked and installed in the packaging cavity, and the pins are pressed on the bottom substrate.

[0008] The bottom substrate is an integrated ceramic board with multi-layer circuits made by high-temperature sintering, the metal frame is a gold-plated Kovar alloy, the cover is parallel-sealed to the top of the metal frame, and the bottom substrate is parallel-sealed to the bottom of the metal frame.

[0009] The pins are solder ball arrays.

[0010] The local oscillator circuit is connected to two receiving frequency conversion channel circuits via a signal transmission medium.

[0011] The signal transmission medium is a spherical low-melting-point eutectic solder alloy, and a vertical interconnection structure is formed between the upper substrate and the lower substrate through spherical bumps of the spherical low-melting-point eutectic solder alloy.

[0012] A receiving circuit for a dual-channel frequency conversion SIP, characterized in that the receiving circuit comprises:

[0013] A local oscillator circuit for receiving a reference signal and outputting a local oscillator signal;

[0014] A receiving frequency conversion channel circuit I for receiving a radio frequency signal I and outputting an intermediate frequency signal I;

[0015] A receiving frequency conversion channel circuit II for receiving a radio frequency signal II and outputting an intermediate frequency signal II;

[0016] The local oscillator circuit is connected to mixer I of receiving frequency conversion channel circuit I and mixer II of receiving frequency conversion channel circuit II respectively through a power divider. The local oscillator circuit divides the generated local oscillator signal into two local oscillator signals through the power divider. The power divider sends one local oscillator signal to mixer I of receiving frequency conversion channel circuit I, and the power divider sends the other local oscillator signal to mixer II of receiving frequency conversion channel circuit II. Receiving frequency conversion channel circuit I mixes radio frequency signal I with the local oscillator signal to output intermediate frequency signal I. Receiving frequency conversion channel circuit II mixes radio frequency signal II with the local oscillator signal to output intermediate frequency signal II. Receiving frequency conversion channel circuit I and receiving frequency conversion channel circuit II form a dual channel.

[0017] Furthermore, the local oscillator circuit also includes a filter, a phase-locked source and an amplifier. According to the signal transmission direction: the filter is connected to the phase-locked source, the phase-locked source is connected to the amplifier, and the amplifier is connected to the power divider.

[0018] Furthermore, the receiving frequency conversion channel circuit I also includes a first amplifier I, a first attenuator I, a first filter I, a second filter I, a second amplifier I, a second attenuator I, a third filter I and a third amplifier I. According to the signal transmission direction: the first amplifier I is connected to the first attenuator I, the first attenuator I is connected to the first filter I, the first filter I is connected to the mixer I, the mixer I is connected to the second filter I, the second filter I is connected to the second amplifier I, the second amplifier I is connected to the second attenuator I, the second attenuator I is connected to the third filter I, and the third filter I is connected to the third amplifier I;

[0019] The receiving frequency conversion channel circuit II includes a first amplifier II, a first attenuator II, a first filter II, a second filter II, a second amplifier II, a second attenuator II, a third filter II and a third amplifier II. According to the signal transmission direction: the first amplifier II is connected to the first attenuator II, the first attenuator II is connected to the first filter II, the first filter II is connected to the mixer II, the mixer II is connected to the second filter II, the second filter II is connected to the second amplifier II, the second amplifier II is connected to the second attenuator II, the second attenuator II is connected to the third filter II, and the third filter II is connected to the third amplifier II.

[0020] Furthermore, the filter is a bandpass filter, and the amplifier is a low-noise amplifier.

[0021] Furthermore, the first filter I, the third filter I, the first filter II and the third filter II are all band-pass filters, and the second filter I and the second filter II are intermediate frequency band-pass filters.

[0022] A dual-channel receiving frequency conversion SIP receiving method is characterized by comprising the following steps:

[0023] S1. When the local oscillator circuit is working, the filter of the local oscillator circuit selects the frequency of the received 100MHz reference signal and sends it to the phase-locked source. The phase-locked source generates a local oscillator signal based on the received reference signal and sends it to the amplifier. The amplifier amplifies the received local oscillator signal and sends it to the power divider. The power divider divides the received local oscillator signal into two local oscillator signals. The power divider sends the two local oscillator signals to mixer I of receiving frequency conversion channel circuit I and mixer II of receiving frequency conversion channel circuit II respectively.

[0024] S2. When the receiving frequency conversion channel circuit I is working, the first amplifier I of the receiving frequency conversion channel circuit I amplifies the received radio frequency signal I and sends it to the first attenuator I. The first attenuator I attenuates the received radio frequency signal I and sends it to the first filter I. The first filter I performs frequency selection on the received radio frequency signal I and sends it to the mixer I. The mixer I mixes the received radio frequency signal I with the received local oscillator signal to produce an intermediate frequency signal I and sends it to the second filter I. The second filter I removes the image frequency and clutter from the received intermediate frequency signal I and sends it to the second amplifier I. The second amplifier I amplifies the received intermediate frequency signal I and sends it to the second attenuator I. The second attenuator I attenuates the received intermediate frequency signal I and sends it to the third filter I. The third filter I performs frequency selection on the received intermediate frequency signal I and sends it to the third amplifier I. The third amplifier I amplifies the received intermediate frequency signal I and outputs a specific intermediate frequency signal I.

[0025] S3. When the receiving frequency conversion channel circuit II is working, the first amplifier II of the receiving frequency conversion channel circuit II amplifies the received radio frequency signal II and sends it to the first attenuator II. The first attenuator II attenuates the received radio frequency signal II and sends it to the first filter II. The first filter II performs frequency selection on the received radio frequency signal I and sends it to the mixer II. The mixer II mixes the received radio frequency signal II with the received local oscillator signal to produce an intermediate frequency signal II and sends it to the second filter II. The second filter II filters out the image frequency and clutter from the received intermediate frequency signal II and sends it to the second amplifier II. The second amplifier II amplifies the received intermediate frequency signal II and sends it to the second attenuator II. The second attenuator II attenuates the received intermediate frequency signal II and sends it to the third filter II. The third filter II performs frequency selection on the received intermediate frequency signal II and sends it to the third amplifier II. The third amplifier II amplifies the received intermediate frequency signal II and outputs a specific intermediate frequency signal II.

[0026] S4, two receiving frequency conversion channel circuits respectively output intermediate frequency signal I and intermediate frequency signal II to form dual channels.

[0027] Furthermore, the lower ends of the second filter I and the second filter II are used to suppress clutter signals below 138 MHz, and the upper ends of the second filter I and the second filter II are used to suppress local oscillator leakage signals.

[0028] Furthermore, the attenuation of the second attenuator is controlled within ±0.01dB / °C.

[0029] The present invention has at least the following advantages or beneficial effects:

[0030] 1. The present invention realizes a miniaturized, multifunctional, and highly integrated dual-channel receiving frequency conversion SIP. The two received RF signals are sequentially passed through an amplifier, an attenuator, and a filter before entering a mixer to be mixed with a local oscillator signal provided by a local oscillator source. The two mixed intermediate frequency signals are then sequentially passed through a filter, an amplifier, a temperature-compensated attenuator, a filter, and an amplifier before being output as intermediate frequency signals. Therefore, the SIP has the functions of dual-channel receiving down-conversion, amplification, and filtering, as well as channel gain control and frequency conversion local oscillator signal generation.

[0031] 2. The present invention adopts 3D stacking technology design. The receiving circuit is divided into two parts, the upper part is the local oscillator circuit, and the lower part is the two-way receiving frequency conversion channel circuit.

[0032] 3. The present invention adopts conduction cooling, placing the receiving frequency conversion circuit with large heat generation on the lower substrate, and the lower substrate is connected to the solder balls at the bottom of the package shell. The heat generated by each receiving frequency conversion channel circuit is quickly transferred to the external printed circuit board and then to the cavity through the solder balls at the bottom of the package shell, thereby improving the heat dissipation efficiency of the device when in use.

[0033] 4. The present invention adopts a signal transmission medium to connect the upper substrate and the lower substrate, wherein the signal transmission medium is a spherical low-melting-point eutectic solder alloy, and a vertical interconnection structure is formed between the upper substrate and the lower substrate through the spherical bumps of the spherical low-melting-point eutectic solder alloy.

[0034] 5. The present invention includes a dual-channel receiving frequency conversion channel circuit and a local oscillator source circuit; the two receiving channels adopt the same circuit design to ensure consistency between the channels.

[0035] 6. The present invention adds a multi-stage attenuator to the receiving frequency conversion channel circuit link of the radio frequency receiver to facilitate gain adjustment, improve matching, and enhance circuit stability.

[0036] 7. The present invention adds a temperature compensation attenuator to the receiving frequency conversion channel circuit link of the radio frequency receiver to improve the temperature adaptability of the circuit. The operating temperature range of the present invention is -55℃ to +85℃, which is suitable for the military field and has good engineering application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1This is a structural diagram of the dual-channel receiving frequency conversion SIP of the present invention;

[0039] Figure 2 for Figure 1 Exploded diagram;

[0040] Figure 3 This is a working principle diagram of the receiving circuit of the dual-channel receiving frequency conversion SIP of the present invention;

[0041] Figure 4 This is a schematic diagram of the receiving circuit of the dual-channel receiving frequency conversion SIP of the present invention.

[0042] The markings in the figure are: 1. Package shell, 2. Upper substrate, 3. Lower substrate, 4. Local oscillator circuit, 5. Receiving frequency conversion channel circuit, 6. Pins, 11. Cover, 12. Metal frame, 13. Bottom substrate. DETAILED DESCRIPTION

[0043] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of 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. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0044] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0045] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0046] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0047] In the description of the embodiments of the present invention, "a plurality of" means at least two.

[0048] Example 1:

[0049] like Figure 1 As shown, a dual-channel receiving frequency conversion SIP includes a packaging shell 1 and an internal substrate assembly installed in the packaging shell 1. The internal substrate assembly includes an upper substrate 2 and a lower substrate 3. The upper substrate 2 and the lower substrate 3 are stacked together. A signal transmission medium is provided between the upper substrate 2 and the lower substrate 3. The upper substrate 2 is provided with a local oscillator circuit 4, and the lower substrate 3 is provided with two receiving frequency conversion channel circuits 5. The local oscillator circuit 4 is respectively connected to the two receiving frequency conversion channel circuits 5. The lower substrate 3 and the packaging shell 1 are interconnected by gold wire bonding. The packaging shell 1 is fixedly connected with a pin 6.

[0050] In this embodiment, the packaging shell 1 includes a customized tube shell and a cover plate 11. The customized tube shell includes a metal frame 12 and a bottom substrate 13. The lower substrate 3 and the bottom substrate 13 are interconnected by gold wire bonding. The cover plate 11 and the bottom substrate 13 are respectively installed on the top and bottom of the metal frame 12 to form a packaging cavity to protect the internal SIP circuit structure and provide airtight protection for the circuit inside the packaging shell 1; the upper substrate 2 and the lower substrate 3 are stacked and installed in the packaging cavity, and the pins 6 are pressed on the bottom substrate 13.

[0051] In this embodiment, the bottom substrate 13 is an integrated ceramic board made of multi-layer circuits through high-temperature sintering. It is resistant to salt spray and can pass mold tests. This material is suitable for high-frequency signal transmission and has good transmission performance. The metal frame 12 is a gold-plated Kovar alloy with good corrosion resistance. The cover plate 11 is parallel-sealed to the top of the metal frame 12 to provide physical protection and heat conduction path for the SIP. The bottom substrate 13 is parallel-sealed to the bottom of the metal frame 12 to provide good airtightness.

[0052] In this embodiment, the pins 6 are solder ball arrays, which enable the SIP to communicate with the outside world.

[0053] In this embodiment, the local oscillator circuit is connected to two receiving frequency conversion channel circuits via a signal transmission medium.

[0054] In this embodiment, the signal transmission medium is a spherical low-melting-point eutectic solder alloy, and a vertical interconnection structure is formed between the upper substrate and the lower substrate through spherical bumps of the spherical low-melting-point eutectic solder alloy.

[0055] In this embodiment, both the upper substrate 2 and the lower substrate 3 are ceramic substrates.

[0056] The SIP of the present invention can comprehensively consider the appearance of the dual-channel receiving frequency conversion SIP from the perspectives of signal isolation, heat dissipation, structural strength, maintainability, etc., and the SIP adopts a layered design as a whole.

[0057] In terms of isolation: the traditional structure places the local oscillator circuit and the radio frequency circuit on the same plane, resulting in poor isolation between the cross-links. The present invention separates the local oscillator circuit and the receiving frequency conversion channel circuit into independent blocks, physically increasing the isolation between the local oscillator circuit and the receiving frequency conversion channel circuit.

[0058] Heat dissipation: The present invention's heat dissipation design primarily utilizes conduction cooling, combining the overall heat dissipation with the characteristics of conduction cooling. The channels are designed as independent ceramic substrates. To dissipate heat from the module promptly, components that generate the most heat are structurally mounted on the lower ceramic substrate. Specifically, the present invention divides the receiving circuit of the dual-channel receiving frequency conversion SIP into upper and lower sections. Because each receiving circuit of the dual-channel receiving frequency conversion channel contains three amplifiers and generates significant heat, the receiving circuit is placed on the lower substrate 3. The local oscillator circuit, however, generates relatively little heat and is therefore placed on the upper substrate 2. The heat generated by each receiving frequency conversion channel on the lower substrate 3 during operation is rapidly transferred to the printed circuit board and then to the cavity via the pins at the bottom, ensuring that the overall power consumption of the entire device is less than 2.5W.

[0059] In terms of structural strength, in traditional single-layer SIPs, high-power chips and sensitive circuits share a common substrate, leading to thermal expansion coefficient mismatches that fatigue gold wire bonds and easily break under vibration. The modular packaging framework of the present invention enhances the overall structural bending strength. Component placement and inter-board connections are carefully considered and designed to improve structural reliability. Finite element simulations demonstrate the maximum 3σ Von Mises equivalent stress under random vibration loads in different vibration directions, demonstrating reliable structural strength.

[0060] Maintainability: Traditional SIPs use a 2D packaging structure, which renders the entire device useless upon failure, resulting in high repair costs. Furthermore, the performance of the local oscillator circuit or the receiving frequency conversion circuit cannot be tested separately after integration. This invention separates the receiving circuit of the dual-channel receiving frequency conversion SIP into upper and lower parts, making it easier to disassemble and repair in the event of a failure, thus improving maintainability.

[0061] Table 1 Test results of dual-channel receiving frequency conversion SIP

[0062]

[0063] Table 1 shows the test results of the dual-channel receive frequency conversion SIP. These measurements demonstrate that the channel gain of the present invention is 44dB±1dB, the amplitude difference between the two channels is ≤1dB, the dual-channel consistency is good, the IF signal bandwidth is ≥30MHz, the channel noise figure is ≤6dB, the IF output P-1 is ≥18dBm, the input P-1 is ≥-5dBm, the image rejection is ≥35dBc, the weight is ≤10g, and the operating temperature is -55°C to +85°C. The SIP measures 21mm*16mm*4.3mm, which is 5% smaller than traditional discrete modules, and weighs no more than 10g, which is 1% less than the weight of traditional discrete modules, achieving a miniaturized and lightweight design.

[0064] In summary, the dual-channel receiving frequency conversion SIP of the present invention realizes the characteristics of multi-function, miniaturization, lightweight, high integration, and high and low temperature resistance.

[0065] Example 2:

[0066] like Figure 3 As shown, a dual-channel receiving frequency conversion SIP receiving circuit, the receiving circuit includes:

[0067] A local oscillator circuit for receiving a reference signal and outputting a local oscillator signal;

[0068] A receiving frequency conversion channel circuit I for receiving a radio frequency signal I and outputting an intermediate frequency signal I;

[0069] A receiving frequency conversion channel circuit II for receiving a radio frequency signal II and outputting an intermediate frequency signal II;

[0070] The local oscillator circuit is connected to mixer I of receiving frequency conversion channel circuit I and mixer II of receiving frequency conversion channel circuit II respectively through a power divider. The local oscillator circuit divides the generated local oscillator signal into two local oscillator signals through the power divider. The power divider sends one local oscillator signal to mixer I of receiving frequency conversion channel circuit I, and the power divider sends the other local oscillator signal to mixer II of receiving frequency conversion channel circuit II. Receiving frequency conversion channel circuit I mixes radio frequency signal I with the local oscillator signal to output intermediate frequency signal I. Receiving frequency conversion channel circuit II mixes radio frequency signal II with the local oscillator signal to output intermediate frequency signal II. Receiving frequency conversion channel circuit I and receiving frequency conversion channel circuit II form a dual channel.

[0071] like Figure 4 As shown,

[0072] Furthermore, the local oscillator circuit also includes a filter, a phase-locked source and an amplifier. According to the signal transmission direction: the filter is connected to the phase-locked source, the phase-locked source is connected to the amplifier, and the amplifier is connected to the power divider; the filter, phase-locked source, amplifier and power divider are all electrically interconnected with the upper substrate through gold wire bonding.

[0073] Furthermore, the receiving frequency conversion channel circuit I also includes a first amplifier I, a first attenuator I, a first filter I, a second filter I, a second amplifier I, a second attenuator I, a third filter I and a third amplifier I. According to the signal transmission direction: the first amplifier I is connected to the first attenuator I, the first attenuator I is connected to the first filter I, the first filter I is connected to the mixer I, the mixer I is connected to the second filter I, the second filter I is connected to the second amplifier I, the second amplifier I is connected to the second attenuator I, the second attenuator I is connected to the third filter I, and the third filter I is connected to the third amplifier I; the first amplifier I, the first attenuator I, the first filter I, the mixer I, the second filter I, the second amplifier I, the second attenuator I, the third filter I and the third amplifier I are all electrically interconnected with the lower substrate through gold wire bonding to form a receiving frequency conversion channel circuit.

[0074] The receiving frequency conversion channel circuit II includes a first amplifier II, a first attenuator II, a first filter II, a second filter II, a second amplifier II, a second attenuator II, a third filter II and a third amplifier II. According to the signal transmission direction: the first amplifier II is connected to the first attenuator II, the first attenuator II is connected to the first filter II, the first filter II is connected to the mixer II, the mixer II is connected to the second filter II, the second filter II is connected to the second amplifier II, the second amplifier II is connected to the second attenuator II, the second attenuator II is connected to the third filter II, and the third filter II is connected to the third amplifier II; the first amplifier II, the first attenuator II, the first filter II, the mixer II, the second filter II, the second amplifier II, the second attenuator II, the third filter II and the third amplifier II are all electrically interconnected with the lower substrate through gold wire bonding to form another receiving frequency conversion channel circuit.

[0075] In this embodiment, the power divider of the local oscillator circuit is connected to the upper substrate by gold wire bonding, and the mixers of the two receiving frequency conversion channel circuits are also connected to the lower substrate respectively by gold wire bonding, and the upper substrate and the lower substrate are connected by a signal transmission medium.

[0076] In this embodiment, the filter is a bandpass filter, and the amplifier is a low-noise amplifier.

[0077] In this embodiment, the first filter I, the third filter I, the first filter II and the third filter II are all band-pass filters, and the second filter I and the second filter II are intermediate frequency band-pass filters.

[0078] like Figure 3 、 Figure 4 As shown, the two receiving frequency conversion channel circuits receive RF signals FL to FH respectively, and the RF signals are fed into receiving frequency conversion channel circuit I and receiving frequency conversion channel circuit II respectively; the 100MHz reference signal generates a 12XXMHz to 14XXMHz local oscillator signal through the local oscillator source circuit, which is evenly divided into two local oscillator signals through a power divider and fed into the mixers of the two receiving frequency conversion channel circuits to mix with the RF signals respectively; finally, the mixed signals are filtered, amplified, temperature compensated, attenuated, filtered, and amplified in sequence to output two 275MHz intermediate frequency signals.

[0079] When RF signal I is fed into receiving frequency conversion circuit I, it is first amplified by a low-noise amplifier and then attenuated by a digitally controlled attenuator. The attenuated RF signal I is frequency-selected by a bandpass filter. The selected RF signal I is fed into a mixer, where RF signal I is mixed with the local oscillator signal sent from the power divider to obtain an intermediate frequency signal I. A bandpass filter is then used to filter out the image frequency and noise of the mixing output and prevent leakage of the local oscillator signal. The filtered intermediate frequency signal I is fed into an amplifier. To improve circuit stability, the signal is passed through a first-stage temperature compensation attenuator to improve the circuit's temperature adaptability. Finally, the intermediate frequency signal I is output after passing through a bandpass filter and an amplifier in sequence. When RF signal II is fed into receiving frequency conversion circuit II, the same process is used as when RF signal I is fed into receiving frequency conversion circuit I.

[0080] On each link of the receiving frequency conversion circuit:

[0081] The first amplifier I is a low-noise amplifier with low noise and high gain, which ensures the gain of the RF front stage and makes the receiving channel have better receiving characteristics;

[0082] Both the first attenuator I and the first attenuator II are digitally controlled attenuators, which not only can flexibly adjust the link gain, but also can improve the impedance matching between components, enhance the stability of the circuit within the dynamic range, and improve the link's reception function for large signals;

[0083] The first filter I and the first filter II are both bandpass filters. At the input end of the mixer, they provide the mixer with a pure input signal without noise, and also suppress the leakage of the local oscillator signal, thereby increasing the isolation.

[0084] The mixer has a frequency conversion function and is the core component of the receiving link. It mixes the RF signal at the link input end with the local oscillator signal and outputs an intermediate frequency signal.

[0085] The second filter I and the second filter II are both intermediate frequency bandpass filters. The low end of the intermediate frequency bandpass filter mainly suppresses the clutter signals below 138MHz, and the high end of the intermediate frequency bandpass filter mainly suppresses the local oscillator leakage signal. This intermediate frequency bandpass filter can not only suppress the image frequency at the output end of the mixer, but also suppress the clutter signals outside the working frequency band, thereby improving the purity and flatness of the output signal.

[0086] The second amplifier I, the third amplifier I, the second amplifier II and the third amplifier II mainly provide sufficient signal gain for the link;

[0087] The second attenuator I and the second attenuator II are both temperature compensated attenuators. Through temperature compensation, the attenuation is controlled within ±0.01dB / ℃, improving the temperature adaptability of the circuit between -55℃ and 75℃.

[0088] The third filter I and the third filter II are both band-pass filters, which ensure the flatness and high suppression of the signal receiving gain.

[0089] The present invention incorporates multi-stage attenuators between links during circuit design, enabling flexible adjustment of link gain while also improving impedance matching between components and enhancing circuit stability. Furthermore, temperature-compensated attenuators are added between links to control attenuation to within ±0.01dB / °C through temperature compensation, improving the circuit's adaptability to temperatures between -55°C and 75°C. The present invention utilizes the same circuit design for both receiving channels, simplifying the design while ensuring consistency between the two channels.

[0090] In the link of the local oscillator circuit, a bandpass filter is used as the filter to suppress the clutter signal and ensure the quality of the reference signal at the input end of the local oscillator source link; the phase-locked source is used to generate the required local oscillator signal; and the amplifier is a low-noise amplifier to generate the local oscillator drive power capable of driving the mixer.

[0091] The 100MHz reference signal passes through a low-pass filter and is fed into the phase-locked source. The phase-locked source generates a local oscillator signal. After being amplified and output by the amplifier, the power divider divides the local oscillator signal into two paths, which are the local oscillator signals provided by the two receiving frequency conversion channel circuits.

[0092] Example 3:

[0093] like Figure 4 As shown,

[0094] A dual-channel receiving method for variable frequency SIP includes the following steps:

[0095] S1. When the local oscillator circuit is working, the bandpass filter of the local oscillator circuit selects the frequency of the received 100MHz reference signal and sends it to the phase-locked source. The phase-locked source generates a local oscillator signal based on the received reference signal and sends it to the low-noise amplifier. The low-noise amplifier amplifies the received local oscillator signal and sends it to the power divider. The power divider divides the received local oscillator signal into two local oscillator signals. The power divider sends the two local oscillator signals to mixer I of receiving frequency conversion channel circuit I and mixer II of receiving frequency conversion channel circuit II respectively.

[0096] S2. When the receiving frequency conversion channel circuit I is working, the low noise amplifier of the receiving frequency conversion channel circuit I amplifies the received radio frequency signal I and sends it to the digitally controlled attenuator. The digitally controlled attenuator attenuates the received radio frequency signal I and sends it to the bandpass filter. The bandpass filter selects the frequency of the received radio frequency signal I and sends it to the mixer I. The mixer I mixes the received radio frequency signal I with the received local oscillator signal to generate an intermediate frequency signal I and sends it to the intermediate frequency bandpass filter. The intermediate frequency bandpass filter removes the image frequency and clutter from the received intermediate frequency signal I and sends it to the amplifier. The amplifier amplifies the received intermediate frequency signal I and sends it to the temperature compensation attenuator. The temperature compensation attenuator attenuates the received intermediate frequency signal I and sends it to the bandpass filter. The bandpass filter selects the frequency of the received intermediate frequency signal I and sends it to the amplifier. The amplifier amplifies the received intermediate frequency signal I and outputs a specific intermediate frequency signal I.

[0097] S3. When the receiving frequency conversion channel circuit II is working, the low noise amplifier of the receiving frequency conversion channel circuit II amplifies the received radio frequency signal II and sends it to the digitally controlled attenuator. The digitally controlled attenuator attenuates the received radio frequency signal II and sends it to the bandpass filter. The bandpass filter selects the frequency of the received radio frequency signal II and sends it to the mixer II. The mixer II mixes the received radio frequency signal II with the received local oscillator signal to generate an intermediate frequency signal II and sends it to the intermediate frequency bandpass filter. The intermediate frequency bandpass filter removes the image frequency and clutter from the received intermediate frequency signal II and sends it to the amplifier. The amplifier amplifies the received intermediate frequency signal II and sends it to the temperature compensation attenuator. The temperature compensation attenuator attenuates the received intermediate frequency signal II and sends it to the bandpass filter. The bandpass filter selects the frequency of the received intermediate frequency signal II and sends it to the amplifier. The amplifier amplifies the received intermediate frequency signal II and outputs a specific intermediate frequency signal II.

[0098] S4, two receiving frequency conversion channel circuits respectively output intermediate frequency signal I and intermediate frequency signal II to form dual channels.

[0099] In this embodiment, the lower end of the intermediate frequency bandpass filter is used to suppress clutter signals below 138 MHz, and the upper end of the intermediate frequency bandpass filter is used to suppress local oscillator leakage signals.

[0100] In this embodiment, the attenuation of the temperature compensation attenuator is controlled within ±0.01 dB / °C.

[0101] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

[0102] It will be apparent to those skilled in the art that the present application is not limited to the details of the exemplary embodiments described above and that the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present application is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A dual-channel receiving frequency conversion SIP, characterized by: The SIP includes a packaging shell and an internal substrate assembly installed in the packaging shell. The internal substrate assembly includes an upper substrate and a lower substrate. The upper substrate and the lower substrate are stacked together. A signal transmission medium is provided between the upper substrate and the lower substrate. The upper substrate is provided with a local oscillator circuit, and the lower substrate is provided with two receiving frequency conversion channel circuits. The local oscillator circuit is connected to the two receiving frequency conversion channel circuits. The lower substrate and the packaging shell are interconnected by gold wire bonding. The packaging shell is fixedly connected with pins.

2. The dual-channel receiving frequency conversion SIP according to claim 1, characterized in that: The packaging shell includes a customized tube shell and a cover plate. The customized tube shell includes a metal frame and a bottom substrate. The lower substrate and the bottom substrate are interconnected by gold wire bonding. The cover plate and the bottom substrate are respectively installed on the top and bottom of the metal frame to form a packaging cavity. The upper substrate and the lower substrate are stacked and installed in the packaging cavity, and the pins are pressed on the bottom substrate.

3. The dual-channel receiving frequency conversion SIP according to claim 2, characterized in that: The bottom substrate is an integrated ceramic board with multi-layer circuits made by high-temperature sintering, and the metal frame is a gold-plated Kovar alloy; the cover is parallel-sealed to the top of the metal frame, and the bottom substrate is parallel-sealed to the bottom of the metal frame, and the pins are solder ball arrays.

4. A dual-channel receiving frequency conversion SIP receiving circuit, characterized by: The receiving circuit includes: A local oscillator circuit for receiving a reference signal and outputting a local oscillator signal; A receiving frequency conversion channel circuit I for receiving a radio frequency signal I and outputting an intermediate frequency signal I; A receiving frequency conversion channel circuit II for receiving a radio frequency signal II and outputting an intermediate frequency signal II; The local oscillator circuit is connected to mixer I of receiving frequency conversion channel circuit I and mixer II of receiving frequency conversion channel circuit II respectively through a power divider. The local oscillator circuit divides the generated local oscillator signal into two local oscillator signals through the power divider. The power divider sends one local oscillator signal to mixer I of receiving frequency conversion channel circuit I, and the power divider sends the other local oscillator signal to mixer II of receiving frequency conversion channel circuit II. Receiving frequency conversion channel circuit I mixes radio frequency signal I with the local oscillator signal to output intermediate frequency signal I. Receiving frequency conversion channel circuit II mixes radio frequency signal II with the local oscillator signal to output intermediate frequency signal II. Receiving frequency conversion channel circuit I and receiving frequency conversion channel circuit II form a dual channel.

5. The receiving circuit of the dual-channel frequency conversion SIP according to claim 4, characterized in that: The local oscillator circuit also includes a filter, a phase-locked source and an amplifier. According to the signal transmission direction: the filter is connected to the phase-locked source, the phase-locked source is connected to the amplifier, and the amplifier is connected to the power divider.

6. The receiving circuit of a dual-channel frequency conversion SIP according to claim 4, characterized in that: The receiving frequency conversion channel circuit I also includes a first amplifier I, a first attenuator I, a first filter I, a second filter I, a second amplifier I, a second attenuator I, a third filter I and a third amplifier I. According to the signal transmission direction: the first amplifier I is connected to the first attenuator I, the first attenuator I is connected to the first filter I, the first filter I is connected to the mixer I, the mixer I is connected to the second filter I, the second filter I is connected to the second amplifier I, the second amplifier I is connected to the second attenuator I, the second attenuator I is connected to the third filter I, and the third filter I is connected to the third amplifier I; The receiving frequency conversion channel circuit II includes a first amplifier II, a first attenuator II, a first filter II, a second filter II, a second amplifier II, a second attenuator II, a third filter II and a third amplifier II. According to the signal transmission direction: the first amplifier II is connected to the first attenuator II, the first attenuator II is connected to the first filter II, the first filter II is connected to the mixer II, the mixer II is connected to the second filter II, the second filter II is connected to the second amplifier II, the second amplifier II is connected to the second attenuator II, the second attenuator II is connected to the third filter II, and the third filter II is connected to the third amplifier II.

7. The receiving circuit of a dual-channel frequency conversion SIP according to claim 5, characterized in that: The filter is a bandpass filter, and the amplifier is a low-noise amplifier.

8. The dual-channel receiving frequency conversion SIP receiving circuit according to claim 6, characterized in that: The first filter I, the third filter I, the first filter II and the third filter II are all band-pass filters, and the second filter I and the second filter II are intermediate frequency band-pass filters.

9. A dual-channel receiving method for variable frequency SIP, characterized in that The following steps are included: S1. When the local oscillator circuit is working, the filter of the local oscillator circuit selects the frequency of the received 100MHz reference signal and sends it to the phase-locked source. The phase-locked source generates a local oscillator signal based on the received reference signal and sends it to the amplifier. The amplifier amplifies the received local oscillator signal and sends it to the power divider. The power divider divides the received local oscillator signal into two local oscillator signals. The power divider sends the two local oscillator signals to mixer I of receiving frequency conversion channel circuit I and mixer II of receiving frequency conversion channel circuit II respectively. S2. When the receiving frequency conversion channel circuit I is working, the first amplifier I of the receiving frequency conversion channel circuit I amplifies the received radio frequency signal I and sends it to the first attenuator I. The first attenuator I attenuates the received radio frequency signal I and sends it to the first filter I. The first filter I performs frequency selection on the received radio frequency signal I and sends it to the mixer I. The mixer I mixes the received radio frequency signal I with the received local oscillator signal to produce an intermediate frequency signal I and sends it to the second filter I. The second filter I removes the image frequency and clutter from the received intermediate frequency signal I and sends it to the second amplifier I. The second amplifier I amplifies the received intermediate frequency signal I and sends it to the second attenuator I. The second attenuator I attenuates the received intermediate frequency signal I and sends it to the third filter I. The third filter I performs frequency selection on the received intermediate frequency signal I and sends it to the third amplifier I. The third amplifier I amplifies the received intermediate frequency signal I and outputs a specific intermediate frequency signal I. S3. When the receiving frequency conversion channel circuit II is working, the first amplifier II of the receiving frequency conversion channel circuit II amplifies the received radio frequency signal II and sends it to the first attenuator II. The first attenuator II attenuates the received radio frequency signal II and sends it to the first filter II. The first filter II performs frequency selection on the received radio frequency signal I and sends it to the mixer II. The mixer II mixes the received radio frequency signal II with the received local oscillator signal to produce an intermediate frequency signal II and sends it to the second filter II. The second filter II filters out the image frequency and clutter from the received intermediate frequency signal II and sends it to the second amplifier II. The second amplifier II amplifies the received intermediate frequency signal II and sends it to the second attenuator II. The second attenuator II attenuates the received intermediate frequency signal II and sends it to the third filter II. The third filter II performs frequency selection on the received intermediate frequency signal II and sends it to the third amplifier II. The third amplifier II amplifies the received intermediate frequency signal II and outputs a specific intermediate frequency signal II. S4, two receiving frequency conversion channel circuits respectively output intermediate frequency signal I and intermediate frequency signal II to form dual channels.

10. The dual-channel receiving frequency conversion SIP receiving circuit according to claim 11, characterized in that: The lower end of the second filter is used to suppress clutter signals below 138 MHz, and the upper end of the intermediate frequency bandpass filter is used to suppress local oscillator leakage signals; the attenuation of the second attenuator is controlled at ±0.01 dB / °C.

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