An active liquid crystal phased array antenna assembly

Abstract

The application provides an active liquid crystal phased array antenna assembly, comprising a plurality of antenna array units, each of which is composed of a liquid crystal phase shifter, an active component, an antenna radiation unit and a feed network, the active component is a low noise amplifier and / or a power amplifier; the active component is arranged between the liquid crystal phase shifter and the antenna radiation unit; the low noise amplifier is used for amplifying an electromagnetic wave signal received by the antenna radiation unit and transmitting the amplified electromagnetic wave signal to the liquid crystal phase shifter; the power amplifier is used for amplifying an electromagnetic wave signal of the liquid crystal phase shifter and transmitting the amplified electromagnetic wave signal to the antenna radiation unit for radiation; and the active component is also used for heating the liquid crystal phase shifter by using its working current, so that the liquid crystal phase shifter works in a target working temperature range. The application enables the active liquid crystal phased array antenna to work normally at low temperature, and reduces the cost and power consumption.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and more specifically, to an active liquid crystal phased array antenna assembly. Background Technology

[0002] A phased array antenna is a special type of antenna system composed of many independent small antenna elements, each of which can be individually controlled in phase. By changing the phase relationship between the individual elements using phase shifters, the direction of the antenna beam can be altered, allowing dynamic adjustment of the radiation direction of the entire antenna array and thus achieving electronic beam scanning.

[0003] Currently, most existing phase shifters are made of semiconductors. However, semiconductors have drawbacks such as high cost and high power consumption, which limits their widespread application in practical communication fields. Liquid crystal phase shifters, on the other hand, have attracted industry attention and are being researched and developed due to their low cost, low power consumption, and good microwave performance.

[0004] However, due to the physical characteristics of liquid crystal materials themselves—the crystal structure of liquid crystal materials changes with temperature—liquid phase shifters suffer from defects such as thickening or even crystallization at low temperatures and excessive microwave insertion loss. This makes it difficult for liquid crystal phased arrays to meet the requirements of high-performance communication applications, such as satellite communication. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide an active liquid crystal phased array antenna assembly to overcome the problem of liquid crystal phase shifter crystallization at low temperature and reduce cost and power consumption.

[0006] In a first aspect, an active liquid crystal phased array antenna assembly is provided, comprising multiple antenna array units, each antenna array unit consisting of a liquid crystal phase shifter, active components, an antenna radiating unit, and a feeding network; the active components are low-noise amplifiers and / or power amplifiers; the active components are disposed between the liquid crystal phase shifter and the antenna radiating unit, the antenna radiating unit is used to receive and transmit electromagnetic wave signals, the low-noise amplifier is used to amplify the electromagnetic wave signals received by the antenna radiating unit and transmit the amplified electromagnetic wave signals to the liquid crystal phase shifter; the power amplifier is used to amplify the electromagnetic wave signals from the liquid crystal phase shifter and transmit them to the antenna radiating unit for radiation; the active components are also used to heat the liquid crystal phase shifter using their own operating current, so that it operates within a target operating temperature range of 10-40℃; the liquid crystal phase shifter is used to adjust the phase of the electromagnetic wave signals on the antenna radiating unit.

[0007] Optionally, all antenna radiating elements are integrated in the same substrate assembly, which consists of a first substrate and a second substrate formed in one piece. Each active component is fixed to the first substrate by welding at a first welding temperature, and the first substrate and the second substrate are fixed to each other by welding at a second welding temperature.

[0008] Optionally, a plurality of metal cavities are provided on the side of the second substrate adjacent to the first substrate; each metal cavity contains an active component; each active component is welded and fixed to the first substrate by a first welding temperature.

[0009] Optionally, the second welding temperature is at least 30°C lower than the first welding temperature.

[0010] Optionally, the antenna radiating element, active components, liquid crystal phase shifter, and feed network all adopt a planar structure.

[0011] Optionally, signal transmission between the antenna radiating element, the liquid crystal phase shifter, and the feed network layer adopts vertical channel transmission.

[0012] Secondly, a manufacturing process for an active liquid crystal phased array antenna assembly is provided, including:

[0013] The mounting positions of active components are marked on the back plate of the first substrate with integrated antenna radiating elements; the active components are low-noise amplifiers and / or power amplifiers.

[0014] Apply adhesive to the installation location;

[0015] The bare die of the active component is placed on the colloid to fix the active component to the back surface of the first substrate.

[0016] Active components are soldered to the first substrate using gold wire in a single process.

[0017] The second substrate with metal cavities and the first substrate with active components already soldered are then soldered together again. The temperature of the second soldering is at least 30°C lower than that of the first soldering. Each metal cavity contains one active component.

[0018] One side of the liquid crystal phase shifter is bonded to the second substrate using an adhesive;

[0019] The other side of the liquid crystal phase shifter is fixed to the feed network layer by adhesive bonding.

[0020] Optionally, after placing the bare die of the active component on the colloid, the process further includes:

[0021] The colloid is cured.

[0022] Optionally, the active components are soldered to the first substrate using gold wire in a single step, including:

[0023] One end of the gold wire is fixed to the pad of the active component's screw, and the gold wire is soldered to the pad of the active component's bare die by ultrasonic energy or hot pressing.

[0024] The other end of the gold wire is pulled to the corresponding pad position on the back plate of the antenna radiating unit, and the gold wire and the pad on the back plate of the antenna radiating unit are soldered by ultrasonic energy or hot pressing.

[0025] Optionally, the antenna radiating element, active components, liquid crystal phase shifter, and feed network all adopt a planar structure.

[0026] The present invention provides an active liquid crystal phased array antenna assembly, which includes multiple antenna array units. Each antenna array unit consists of a liquid crystal phase shifter, active components, an antenna radiating unit, and a feeding network. The active components are low-noise amplifiers and / or power amplifiers. The active components are disposed between the liquid crystal phase shifter and the antenna radiating unit. The antenna radiating unit is used to receive and transmit electromagnetic wave signals. The low-noise amplifier is used to amplify the electromagnetic wave signals received by the antenna radiating unit and transmit the amplified electromagnetic wave signals to the liquid crystal phase shifter. The power amplifier is used to amplify the electromagnetic wave signals from the liquid crystal phase shifter and transmit them to the antenna radiating unit for radiation. The active components are also used to heat the liquid crystal phase shifter using their own operating current, so that it operates within a target operating temperature range of 10-40°C. The liquid crystal phase shifter is used to adjust the phase of the electromagnetic wave signals on the antenna radiating unit. This invention overcomes the physical defects of liquid crystals in phased array antenna applications (difficulty in low-temperature operation and high insertion loss), enabling liquid crystal phased array antennas to operate normally even at low temperatures of -40°C; it also reduces cost and power consumption; and meets the needs of high-performance communication scenarios.

[0027] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1(a) shows a schematic diagram of the signal receiving circuit of each antenna array unit of the active liquid crystal phased array antenna assembly provided in the embodiment of the present invention;

[0030] Figure 1(b) shows a schematic diagram of the signal transmission circuit of each antenna array unit of the active liquid crystal phased array antenna assembly provided in the embodiment of the present invention;

[0031] Figure 2 This diagram shows a schematic representation of the antenna array unit of the active liquid crystal phased array antenna assembly provided in an embodiment of the present invention.

[0032] Figure 3 This diagram illustrates the array distribution structure of an active liquid crystal phased array antenna assembly provided in an embodiment of the present invention.

[0033] Figure 4(a) shows an overall signal reception schematic diagram of an active liquid crystal phased array antenna assembly provided in an embodiment of the present invention;

[0034] Figure 4(b) shows an overall signal transmission schematic diagram of an active liquid crystal phased array antenna assembly provided in an embodiment of the present invention;

[0035] Figure 5 A schematic flowchart illustrating the manufacturing process of the active liquid crystal phased array antenna assembly provided in an embodiment of the present invention is shown.

[0036] Figure 6 This diagram illustrates the structure of welding active components and antenna radiating elements according to an embodiment of the present invention.

[0037] Explanation of key component symbols: 101, Antenna radiating element; 102, Low noise amplifier; 103, Liquid crystal phase shifter; 104, Metal cavity; 105, Gold wire; 106, Feed network; 107, Power amplifier; 1011, First substrate; 1012, Second substrate. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. 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 claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0039] Considering the inherent physical properties of liquid crystal materials—their state changes with temperature, leading to defects such as thickening or even crystallization at low temperatures and excessive insertion loss in liquid crystal phase shifters—liquid crystal phased arrays struggle to meet the requirements of high-performance communication applications. Therefore, this invention provides a phased array antenna assembly, which is described below through embodiments.

[0040] This invention provides a phased array antenna assembly, as shown in Figures 4(a) and 4(b), comprising multiple antenna array units. Each antenna array unit consists of an antenna radiating unit 101, active components, a liquid crystal phase shifter 103, and a feed network 106. The active components are a low-noise amplifier 102 and / or a power amplifier 107. The active components are disposed between the liquid crystal phase shifter 103 and the antenna radiating unit 101. The antenna radiating unit 101 is used to receive and transmit electromagnetic wave signals.

[0041] The low-noise amplifier 102 amplifies the electromagnetic wave signal received by the antenna radiating unit 101 and transmits the amplified electromagnetic wave signal to the liquid crystal phase shifter 103; the power amplifier 107 amplifies the electromagnetic wave signal from the liquid crystal phase shifter 103 and transmits it to the antenna radiating unit 101 for radiation; on the other hand, both the low-noise amplifier 102 and the power amplifier 107 can use their own operating current to heat the liquid crystal phase shifter 103, so that it operates within a target operating temperature range of 10-40℃; the liquid crystal phase shifter is used to adjust the phase of the electromagnetic wave signal received on the antenna radiating unit 101.

[0042] As shown in Figure 1(a), an LNA (Low Noise Amplifier) ​​is added between each antenna radiating element 101 and the liquid crystal phase shifter 103. This allows the signal to be amplified immediately after passing through the antenna radiating element 101, ensuring a relatively good signal-to-noise ratio even if the received signal is weak. This makes liquid crystal phased arrays truly applicable to most communication applications. This scheme effectively improves receiver sensitivity and overcomes the drawback of reduced G / T (Gain-to-Noise-Temperature ratio) caused by excessive liquid crystal insertion loss. It effectively increases the G / T value of the liquid crystal phased array by approximately 5-6 dB / K, making the application of liquid crystal phased arrays in the communication field, especially in satellite communication, possible. It is suitable for all communication applications from 2.5 to 70 GHz, including satellite communication, 5G, and future 6G.

[0043] Simultaneously, the heat generated by the operating current of the LNA (low-noise amplifier) ​​or PA (power amplifier) ​​effectively heats the liquid crystal phase shifter, overcoming the "cold sensitivity" of liquid crystals and enabling the liquid crystal phase shifter to operate within its effective operating range (10-40℃). This also avoids the additional power consumption required by separate heating structures, reducing the complexity and cost of the entire system. It effectively overcomes the drawback of traditional passive liquid crystal phase arrays that struggle to function properly at low temperatures.

[0044] As shown in Figure 1(b), a power amplifier 107 is added between each antenna radiating element 101 and the liquid crystal phase shifter 103.

[0045] This invention overcomes the physical defects that are currently difficult to overcome in the application of liquid crystals in phased array antennas, enabling the liquid crystal phased array antenna of this invention to work normally even at low temperatures of -40°C; reducing costs and power consumption; and meeting the needs of high-performance communication scenarios.

[0046] In one feasible implementation, such as Figure 2 As shown, all antenna radiating elements 101 are integrated in the same substrate assembly, which consists of an integrally formed first substrate 1011 and an integrally formed second substrate 1012. Each active component is welded to the first substrate at a first welding temperature, and the first substrate and the second substrate are welded to each other at a second welding temperature.

[0047] In this embodiment of the invention, the first substrate and the second substrate can be PCB boards or ceramic substrates, and the ceramic substrates include high-temperature ceramic substrates and low-temperature ceramic substrates.

[0048] In a specific example, the first substrate 1011 and the second substrate 1012 are made of low-temperature ceramic substrates with a sintering temperature of 850-900℃. Since low-temperature ceramics are quartz-based glass-ceramics, their coefficients of thermal expansion are essentially the same as those of glass itself, approximately 8.9 x 10⁻⁶. -6 (dL / L), therefore, bonding the low-temperature ceramic substrate with the glass substrate of the liquid crystal phase shifter prevents the warping and tearing problems of the liquid crystal phased array antenna.

[0049] In this embodiment of the invention, a plurality of metal cavities are provided on the side of the second substrate adjacent to the first substrate; each metal cavity contains an active component; each active component is welded and fixed to the first substrate by a first welding temperature.

[0050] Metal cavities can be formed by directly coating the inner wall of the cavity with a metal layer, or by setting a ring of metal through holes around the outer perimeter of the cavity and filling the through holes with metal to form a ring of metal sidewalls. Metal cavities can prevent microwave signals from interfering with each other between antenna array elements.

[0051] In one feasible implementation, the low-noise amplifier 102 is soldered to the back surface of the first substrate 1011 and connected to the microwave circuits designed between the layers of the substrate to realize the transmission of microwave signals.

[0052] The low-noise amplifier (LNA) is directly soldered to the backplane of the first substrate 1011, greatly shortening the distance the signal received by the antenna radiating element 101 travels from the antenna radiating element 101 to the LNA. The electromagnetic wave signal is then transmitted from the LNA to the microwave circuit of the second substrate 1012, and transmitted to the liquid crystal phase shifter through coupling via the ceramic dielectric, minimizing signal loss. Furthermore, by directly soldering the unpackaged LNA 102 die to the backplane of the antenna radiating element 101, the manufacturing difficulty is greatly reduced, effectively controlling manufacturing costs and enabling mass production of the liquid crystal phased array antenna.

[0053] In another embodiment of the invention, the second welding temperature is at least 30°C lower than the first welding temperature to ensure that the welding material of the active components does not melt.

[0054] In this embodiment of the invention, the electromagnetic wave signal transmission between the antenna radiating element 101, the liquid crystal phase shifter 103, and the feed network 106 adopts a planar vertical channel transmission. This planar and vertical layout can effectively overcome the disadvantages of high complexity and high cost of the TR component modules in traditional phased arrays.

[0055] In one feasible implementation, the antenna radiating element 101, active components, liquid crystal phase shifter 103, and feed network 106 all adopt a planar structure.

[0056] In this embodiment of the invention, by adopting a planar structure, the complexity of micro-assembly is simplified, making mass production possible; at the same time, the overall thickness of the antenna is reduced, making the phased array antenna assembly thinner and greatly reducing manufacturing costs.

[0057] It should be noted that the number of antenna arrays in this embodiment of the invention is not limited, but can be composed of array elements of an n*n array, where n is any natural number greater than 1, n=2,3,4...

[0058] In one feasible implementation, such as Figure 3 As shown, the phased array antenna assembly consists of an 8x8 array of antenna array elements.

[0059] As shown in Figures 4(a) and 4(b), the active liquid crystal phased array antenna assembly also includes: a signal receiving / transmitting array unit and a control unit C, and a feed network 106;

[0060] Figure 4(a) is a schematic diagram of the signal receiving channel. For the antenna receiving function, the feed network 106 is used to combine the electromagnetic wave signal generated by the antenna radiating element into a microwave output signal after passing through a low-noise amplifier and a liquid crystal phase shifter; then, it generates an intermediate frequency signal through frequency conversion and is handed over to the baseband processing stage for final processing.

[0061] In one example, the power supply network 106 employs a ceramic power supply network 106.

[0062] Control unit C is used to control the beam direction of the active liquid crystal phased array antenna assembly.

[0063] The control unit C controls the beamforming and beam direction by controlling the phase of each liquid crystal phase shifter. It ensures that the beam can be scanned in a predetermined manner and can be accurately pointed to the target direction.

[0064] As shown in Figure 4(b), it is a schematic diagram of the signal transmission channel. Its working principle is the opposite of that of the receiving channel. The power supply network 106 transmits the electromagnetic wave signal generated by TX to the liquid crystal phase shifter 103, and then transmits it to the antenna radiating unit 101 through the power amplifier PA.

[0065] Currently, most commercially available liquid crystal phased array antennas are passive phased arrays using liquid crystals as phase shifters. Passive phased arrays have only one signal transmitting / receiving device, which distributes the signal to each antenna radiating element 101 through a series of phase shifters. Signal amplification is accomplished by a single power amplifier or low-noise amplifier. This application, however, transforms each antenna radiating element 101 into an active liquid crystal phased array antenna by soldering a low-noise amplifier 102 and / or a power amplifier 107 to the backplate. This allows for individual amplification of the electromagnetic wave signals received or transmitted by each antenna radiating element 101. Furthermore, the addition of a low-noise amplifier 102 and / or a power amplifier 107 after each antenna radiating element 101 significantly improves the overall thermal performance of the liquid crystal phased array antenna at low temperatures, effectively overcoming the shortcomings of traditional passive liquid crystal phased arrays that struggle to operate normally at low temperatures. To address the issue of liquid crystals being "sensitive to cold," the operating current of the LNA and / or PA is used to effectively heat the liquid crystal, enabling it to operate within its effective operating range (10-40℃). At the same time, this avoids the additional power consumption required by an external heating structure, reducing the complexity and cost of the entire system.

[0066] Based on the same inventive concept, a manufacturing process for a phased array antenna assembly is provided, such as... Figure 5 As shown, it includes the following steps:

[0067] Step S501: Mark the mounting positions of active components on the backplane of the first substrate on which the antenna radiating element 101 is integrated. The active components are low-noise amplifiers and / or power amplifiers.

[0068] In this step, before marking the installation position on the backplate of the antenna radiating element 101, the backplate of the antenna radiating element 101 is cleaned to ensure it is free of dust and dirt. In one example, isopropyl alcohol and cotton swabs can be used to clean the surface of the backplate.

[0069] By pre-calibrating the welding position, the accuracy of the welding position can be ensured.

[0070] Step S502: Apply adhesive to the installation location.

[0071] In this step, an appropriate amount of adhesive can be applied to the designated location on the backplate using a dispensing machine. The adhesive should be a low-loss specialty adhesive suitable for microwave applications, taking into account its conductivity, curing time, and temperature.

[0072] Step S503: Place the bare die of the active component on the colloid to fix the active component to the back surface of the first substrate.

[0073] In this step, the die of the active component can be gently placed on the colloid using fine-tipped tweezers to ensure good contact between the die and the backplane.

[0074] Step S504: Use gold wire 105 to solder the active components to the first substrate once.

[0075] In this step, select a gold wire of appropriate diameter 105, typically between 25 and 50 micrometers.

[0076] The present invention solves the technical and cost problems caused by the inability to drill holes in liquid crystal glass by directly welding the low-noise amplifier 102 or the power amplifier 107 to the back plate of the antenna radiating unit 101, simplifies the assembly process, and facilitates large-scale production.

[0077] Step S505: Perform a second welding between the second substrate with the metal cavity and the first substrate on which active components have already been welded.

[0078] The temperature of the secondary welding is at least 30°C lower than that of the primary welding to ensure that the welding material of the active components does not melt; each metal cavity contains one active component.

[0079] Step S506: One side of the liquid crystal phase shifter is bonded to the second substrate with an adhesive.

[0080] Step S507: Fix the other side of the liquid crystal phase shifter to the feed network layer with adhesive.

[0081] The antenna radiating element, active components, liquid crystal phase shifter, and feed network all adopt a planar structure.

[0082] Based on the above embodiments, after placing the bare die of the active component on the colloid, the method further includes:

[0083] The colloid is cured.

[0084] In this embodiment of the invention, the material is cured when heated to 100°C, thus becoming a thermal conductor with general properties.

[0085] In this embodiment of the invention, the curing method includes room temperature curing, heat curing, etc. Appropriate curing can make the antenna radiating unit 101 bond more firmly to the low-noise amplifier 102 and the power amplifier.

[0086] Based on the above embodiments, the process of soldering active components to the first substrate 1011 using gold wire 105 includes:

[0087] like Figure 6 As shown, one end of the gold wire 105 is fixed to the pad of the active component screw, and the gold wire 105 is soldered to the pad of the active component die or the power amplifier screw by ultrasonic energy or hot pressing.

[0088] The other end of the gold wire 105 is pulled to the corresponding pad position on the back plate of the antenna radiating unit 101 to form an arc. The gold wire 105 and the pad on the back plate of the antenna radiating unit 101 are soldered by ultrasonic energy or hot pressing.

[0089] After welding is completed, all weld points can be further inspected to ensure there are no problems such as cold solder joints or short circuits.

[0090] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0091] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0092] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0093] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0094] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention. All should be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An active liquid crystal phased array antenna assembly, characterized in that, The device comprises multiple antenna array units, each consisting of a liquid crystal phase shifter, active components, an antenna radiating element, and a feed network. The active components are low-noise amplifiers and / or power amplifiers. The active components are positioned between the liquid crystal phase shifter and the antenna radiating element. The antenna radiating element receives and transmits electromagnetic wave signals. The low-noise amplifier amplifies the received electromagnetic wave signals and transmits the amplified signals to the liquid crystal phase shifter. The power amplifier amplifies the electromagnetic wave signals from the liquid crystal phase shifter and transmits them to the antenna radiating element for radiation. The active components also use their own operating current to heat the liquid crystal phase shifter, ensuring it operates within a target operating temperature range of 10-40°C. The liquid crystal phase shifter adjusts the phase of the electromagnetic wave signals on the antenna radiating element. All antenna radiating units are integrated in the same substrate assembly, which consists of a first substrate and a second substrate formed in one piece. Each active component is fixed to the first substrate by welding at a first welding temperature. The first and second substrates are made of low-temperature ceramic substrates, which are quartz-based glass ceramics. The liquid crystal phase shifter is based on a glass substrate and liquid crystal. The second substrate has a plurality of metal cavities on the side adjacent to the first substrate; each metal cavity contains one active component; the metal cavity is formed by forming a metal sidewall by forming a ring of through holes around the outer periphery of the cavity and filling the through holes with metal. The manufacturing process of the active liquid crystal phased array antenna assembly includes: The mounting positions of active components are marked on the back plate of the first substrate with integrated antenna radiating elements. Apply adhesive to the installation location; The bare die of the active component is placed on the colloid and the colloid is cured to fix the active component to the back surface of the first substrate. The active components are soldered to the first substrate using gold wire bonding in a single process; specifically, this includes: One end of the gold wire is fixed to the pad of the active component die, and the gold wire is soldered to the pad of the active component die by ultrasonic energy or hot pressing. Pull the other end of the gold wire to the corresponding pad on the back plate of the antenna radiating unit, and weld the gold wire to the pad on the back plate of the antenna radiating unit using ultrasonic energy or hot pressing. The second substrate with metal cavities and the first substrate with active components already soldered on are then soldered together again; each metal cavity contains one active component. One side of the liquid crystal phase shifter is bonded to the second substrate using an adhesive; The other side of the liquid crystal phase shifter is fixed to the feed network layer by adhesive bonding.

2. The active liquid crystal phased array antenna assembly according to claim 1, characterized in that, The first substrate and the second substrate are fixed together by welding at a second welding temperature.

3. The active liquid crystal phased array antenna assembly according to claim 2, characterized in that, The second welding temperature is at least 30°C lower than the first welding temperature.

4. The active liquid crystal phased array antenna assembly according to claim 2, characterized in that, The antenna radiating element, active components, liquid crystal phase shifter, and power supply network all adopt a planar structure.

5. The active liquid crystal phased array antenna assembly according to claim 1, characterized in that, The signal transmission between the antenna radiating element, the liquid crystal phase shifter, and the feed network adopts vertical channel transmission.

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