Compact miniaturized electrically tunable AIP active antenna

Abstract

The invention relates to the technical field of microwave antennas, and provides a compact miniaturized electrically tunable AIP active antenna, which comprises a multilayer printed circuit board, an antenna structure and a microcircuit structure, one side of the printed circuit board is provided with a notch groove, and the notch groove and a resonance matching circuit on the printed circuit board form an antenna structure; the antenna structure is connected to a voltage modulation circuit in the microcircuit structure and is used for adjusting the resonant frequency of the antenna structure; and the antenna structure is connected with the radio frequency link in the microcircuit structure through a quasi-coaxial structure, receives a radio frequency signal according to the adjusted resonant frequency, or generates corresponding resonance to radiate the signal outwards. The AIP antenna provided by the invention has the characteristics of compact structure and low profile, is small in size, light in weight and convenient to integrate and carry, each AIP antenna is relatively independent, the number and the arrangement mode of the antennas can be adjusted according to different requirements to form a new antenna array form, and the AIP antenna has good flexibility and universality.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave antennas, and in particular to a compact miniaturized electrically adjustable AIP active antenna. Background Art

[0002] With the development of wireless communication technology, RF systems are required to be smaller and more powerful. Antennas are an important part of RF front-end circuits. The more mature technology currently is to connect the antenna to the RF transceiver through RF connectors and circuit boards. The RF interconnection distance is long and the loss is large. The packaged antenna AIP technology integrates the antenna and chip in the package based on packaging materials and processes, taking into account antenna performance, cost and size, and providing solutions for realizing system-level wireless functions.

[0003] The development trend of multifunctional systems requires the installation of antennas with multiple frequency bands. Currently, the antennas are large in size, complex in structure, and cannot be effectively matched with the receiver. The space occupied by the antennas hinders the miniaturization, low profile, and light weight of the system. The reliability requirements for antennas are constantly increasing, and they also need to be easy to tune, simple to manufacture and assemble, and low in cost. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a compact miniaturized electrically adjustable AIP active antenna, the antenna structure of which can be implemented on the surface of a printed circuit board, and connected to a back voltage modulation circuit and a radio frequency link through a quasi-coaxial structure and a low-frequency via hole to achieve radiation at different frequencies. The electrically adjustable AIP active antenna has the characteristics of low profile, high integration, and easy assembly.

[0005] The above-mentioned object of the present invention is achieved through the following technical solutions: The present invention provides a compact miniaturized electrically adjustable AIP active antenna, comprising: a multi-layer printed circuit board, an antenna structure and a microcircuit structure; A notch is provided on one side of the printed circuit board, and the antenna structure is formed with the resonant matching circuit on the printed circuit board; the antenna structure is connected to the voltage modulation circuit in the microcircuit structure, and is used to adjust the resonant frequency of the antenna structure; the antenna structure is connected to the radio frequency link in the microcircuit structure through a quasi-coaxial structure, and receives radio frequency signals according to the adjusted resonant frequency, or generates corresponding resonance to radiate signals outward; wherein, The notch structure includes a circular hole located in the middle of the printed circuit board and a rectangular gap connected to the circular hole, and the rectangular gap extends to the edge of the printed circuit board; the resonant matching circuit includes a first capacitor, a surface microstrip line, a second capacitor and a varactor diode, the first capacitor is connected to the rectangular gap and connected to the second capacitor and the varactor diode through the surface microstrip line to form a complete resonant matching circuit; the second capacitor and the varactor diode are respectively connected to the coaxial structure and the low-frequency via connection on the printed circuit board to complete the transmission and adjustment of the signal.

[0006] Preferably, the voltage modulation circuit includes a digital-to-analog conversion chip and an emitter-follower circuit, and the emitter-follower circuit is composed of a first resistor, a second resistor, a first operational amplifier and a second operational amplifier; the received control signal enters the voltage modulation circuit through a connector, and the digital-to-analog conversion chip converts the control signal into a corresponding analog voltage, which is modulated by the emitter-follower circuit and then the voltage of the varactor diode is adjusted through the low-frequency signal line and low-frequency via inside the printed circuit board.

[0007] Preferably, in the transmitting state, the intermediate frequency signal generated by the baseband enters the radio frequency link through the feed port through the internal strip line and radio frequency via of the printed circuit board; the radio frequency link includes a filter, a power amplifier, a mixer and an annular separator, and the local oscillator provides a signal source for the mixer, and the intermediate frequency signal is filtered, amplified and mixed to generate a radio frequency signal, which enters the antenna structure through the microstrip line and coaxial structure on the back of the printed circuit board to generate resonance and radiate externally.

[0008] Preferably, in the receiving state, the antenna structure resonates at the corresponding resonant frequency to receive external electromagnetic signals; the RF link includes a limiter, a low noise amplifier, a filter, and a mixer, and the local oscillator provides a signal source for the mixer, and the electromagnetic signal is filtered, amplified, and mixed to generate an intermediate frequency signal, which reaches the feed port through the RF via and the internal strip line of the printed circuit board and enters the baseband for data processing.

[0009] Preferably, the conversion formula of the digital-to-analog conversion chip is: Vout1=Vref*k / n; Among them, Vout1 is the output voltage, Vref is the reference voltage of the digital-to-analog conversion chip, k is the adjustment coefficient, and n is the denominator factor, which is used to determine the precision of voltage regulation.

[0010] Preferably, the relationship between the output voltage of the first operational amplifier and the first resistor and the second resistor is: Vout2=-Vout1*R2 / R1; Wherein, Vout2 is the output voltage of the first operational amplifier, Vout1 is the output voltage of the digital-to-analog conversion chip, R2 is the resistance value of the second resistor, and R1 is the resistance value of the first resistor; The relationship between the output voltage of the second operational amplifier and the output voltage of the first operational amplifier is: Vout3=-Vout2; In summary, the output voltage after the emitter-follower circuit is: Vout3 = Vout1*R2 / R1.

[0011] Compared with the prior art, the present invention has at least one of the following beneficial effects: The AIP antenna proposed in the present invention has the characteristics of compact structure, low profile, small size, light weight, easy integration and carrying. Each AIP antenna is relatively independent, and the number and arrangement of antennas can be adjusted according to different needs to form a new antenna array form, which has good flexibility and universality.

[0012] (1) The present invention integrates the antenna structure, voltage modulation circuit and radio frequency link on the front and back of the printed circuit board, which can effectively reduce the radio frequency interconnection distance and reduce the loss; (2) The present invention uses a voltage modulation circuit to control the voltage of the varactor diode in the resonant matching circuit in the antenna structure through an external analog signal, directly changing the antenna radiation frequency so that a single antenna can radiate at different frequencies, meeting the requirements of multi-functional integration of wireless systems; (3) The present invention has the advantages of miniaturization, low profile, easy integration, low cost, simple structure and easy processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings: Figure 1 It is a top view schematic diagram of a compact miniaturized electrically adjustable AIP active antenna according to an embodiment of the present invention; Figure 2 It is a bottom-up schematic diagram of a compact miniaturized electrically adjustable AIP active antenna according to an embodiment of the present invention; Figure 3 It is a right side schematic diagram of a compact miniaturized electrically adjustable AIP active antenna according to an embodiment of the present invention; Figure 4 It is a schematic diagram of a power modulation circuit of a compact and miniaturized electrically adjustable AIP active antenna in an embodiment of the present invention; Figure 5 It is a schematic diagram of a radio frequency link of a compact miniaturized electrically adjustable AIP active antenna in an embodiment of the present invention; In the figure: 1: printed circuit board; 2: round hole; 3: rectangular gap; 4: surface microstrip line; 5: low-frequency via; 6: quasi-coaxial structure; 7: first capacitor; 8: second capacitor; 9: variable capacitance diode; 10: RF via; 11: connector; 12: back microstrip line; 13: RF link; 131: limiter; 132: low noise amplifier; 133: filter; 134: mixer; 135: local oscillator; 136: power amplifier; 137: ring spacer; 14: internal stripline; 15: feed port; 16: low-frequency signal line; 17: voltage modulation circuit; 171: digital-to-analog conversion chip; 172: first resistor; 173: second resistor; 174: first operational amplifier; 175: second operational amplifier. DETAILED DESCRIPTION

[0014] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0015] Those skilled in the art will appreciate that, unless otherwise stated, the singular forms "a", "an", "said" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0016] First embodiment like Figure 1 As shown, the present invention provides a compact miniaturized electrically adjustable AIP active antenna, in which the front surface of a multilayer printed circuit board 1 includes an antenna structure; a notch is provided on one side of the printed circuit board 1, and the antenna structure is formed together with the resonant matching circuit on the printed circuit board 1; the antenna structure is connected to a voltage modulation circuit 17 in a microcircuit structure, and is used to adjust the resonant frequency of the antenna structure; the antenna structure is connected to a radio frequency link 13 in the microcircuit structure through a quasi-coaxial structure 6, and receives a radio frequency signal according to the adjusted resonant frequency, or generates a corresponding resonance to radiate a signal outward; wherein, The notch structure includes a circular hole 2 located in the middle of the printed circuit board 1 and a rectangular gap 3 connected to the circular hole 2, and the rectangular gap 3 extends to the edge of the printed circuit board 1; the resonant matching circuit includes a first capacitor 7, a surface microstrip line 4, a second capacitor 8 and a varactor diode 9, the first capacitor 7 is connected to the rectangular gap 3 and connected to the second capacitor 8 and the varactor diode 9 through the surface microstrip line 4 to form a complete resonant matching circuit; the second capacitor 8 and the varactor diode 9 are respectively connected to the coaxial structure 6 and the low-frequency via 5 on the printed circuit board 1 to complete the transmission and adjustment of the signal.

[0017] Combination Figure 2 and Figure 3 As shown, the received control signal enters the voltage modulation circuit 17 through the connector 11, and the digital-to-analog conversion chip 171 converts the control signal into a corresponding analog voltage. After modulation by the radio-follower circuit, the voltage generated by the varactor diode 9 is adjusted through the low-frequency signal line 16 and the low-frequency via 5 inside the printed circuit board 1. The intermediate frequency signal generated by the baseband, that is, the radio frequency signal, enters the radio frequency link 13 through the feed port 15, the internal strip line 14 of the printed circuit board 1 and the radio frequency via 10; the processed radio frequency signal enters the antenna structure through the back microstrip line 12 of the printed circuit board 1 and the quasi-coaxial structure 6 to generate resonance and radiate outward.

[0018] like Figure 4 As shown, the voltage modulation circuit 17 includes a digital-to-analog conversion chip 171 and an emitter-follower circuit, and the emitter-follower circuit is composed of a first resistor 172, a second resistor 173, a first operational amplifier 174 and a second operational amplifier 175; The conversion formula of the digital-to-analog conversion chip 171 is: Vout1=Vref*k / n; Among them, Vout1 is the output voltage, Vref is the reference voltage of the digital-to-analog conversion chip, k is the adjustment coefficient, and n is the denominator factor, which is used to determine the precision of voltage regulation.

[0019] The relationship between the output voltage of the first operational amplifier 174 and the first resistor 172 and the second resistor 173 is: Vout2=-Vout1*R2 / R1; Wherein, Vout2 is the output voltage of the first operational amplifier 174, Vout1 is the output voltage of the digital-to-analog conversion chip 171, R2 is the resistance value of the second resistor, and R1 is the resistance value of the first resistor; The relationship between the output voltage of the second operational amplifier 175 and the output voltage of the first operational amplifier 174 is: Vout3=-Vout2; In summary, the output voltage after the emitter-follower circuit is: Vout3 = Vout1*R2 / R1.

[0020] like Figure 5 As shown, in the transmitting state, the baseband generates an intermediate frequency signal IF through the feed port 15, passes through the internal strip line 14 of the printed circuit board and the RF via 10 to enter the RF link 13; the RF link 13 includes a filter 133, a power amplifier 136, a mixer 134 and an annular spacer 137, and the local oscillator 135 provides a signal source for the mixer 134, and the intermediate frequency signal is filtered, amplified and mixed to generate a radio frequency signal RF, which enters the antenna structure through the back microstrip line 12 and the coaxial structure 6 to generate resonance and radiate externally. In the receiving state, the antenna structure resonates at the corresponding resonant frequency to receive an external electromagnetic signal, namely, a radio frequency signal; the radio frequency signal RF enters the radio frequency link 13 through the quasi-coaxial structure 6 and the back microstrip line 12; the radio frequency link 13 includes a limiter 131, a low noise amplifier 132, a filter 133, a mixer 134, etc., and the local oscillator 135 provides a signal source for the mixer 134, and the radio frequency signal is filtered, amplified, and mixed to generate an intermediate frequency signal, which reaches the feed port 15 through the radio frequency via 10 and the internal strip line 14 of the printed circuit board 1 and then enters the baseband for data processing.

[0021] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

[0022] It should be noted that the above embodiments can be freely combined as needed. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention.

Claims

1. A compact miniaturized electrically adjustable AIP active antenna, characterized in that: include: Multilayer printed circuit boards, antenna structures and microcircuit structures; A notch groove is provided on one side of the printed circuit board, and forms an antenna structure with the resonant matching circuit on the printed circuit board; The antenna structure is connected to the voltage modulation circuit in the microcircuit structure to adjust the resonant frequency of the antenna structure; the antenna structure is connected to the radio frequency link in the microcircuit structure through a quasi-coaxial structure, and receives radio frequency signals according to the adjusted resonant frequency, or generates corresponding resonance to radiate signals outward; wherein, The notch structure includes a circular hole located in the middle of the printed circuit board and a rectangular gap connected to the circular hole, and the rectangular gap extends to the edge of the printed circuit board; the resonant matching circuit includes a first capacitor, a surface microstrip line, a second capacitor and a varactor diode, the first capacitor is connected to the rectangular gap and connected to the second capacitor and the varactor diode through the surface microstrip line to form a complete resonant matching circuit; the second capacitor and the varactor diode are respectively connected to the coaxial structure and the low-frequency via connection on the printed circuit board to complete the transmission and adjustment of the signal.

2. The compact miniaturized electrically adjustable AIP active antenna according to claim 1, characterized in that: The voltage modulation circuit includes a digital-to-analog conversion chip and an emitter-follower circuit, and the emitter-follower circuit is composed of a first resistor, a second resistor, a first operational amplifier and a second operational amplifier; the received control signal enters the voltage modulation circuit through a connector, and the digital-to-analog conversion chip converts the control signal into a corresponding analog voltage, which is modulated by the emitter-follower circuit and then the voltage of the varactor diode is adjusted through the low-frequency signal line inside the printed circuit board and the low-frequency via.

3. The compact miniaturized electrically adjustable AIP active antenna according to claim 1, characterized in that: In the transmitting state, the intermediate frequency signal generated by the baseband enters the radio frequency link through the feed port, the internal strip line of the printed circuit board and the radio frequency via; the radio frequency link includes a filter, a power amplifier, a mixer and a ring isolator, and the local oscillator provides a signal source for the mixer. The intermediate frequency signal is filtered, amplified and mixed to generate the radio frequency signal, which enters the antenna structure through the back microstrip line of the printed circuit board and the coaxial structure to generate the resonance and radiate outward.

4. The compact miniaturized electrically adjustable AIP active antenna according to claim 3, characterized in that: In the receiving state, the antenna structure resonates at the corresponding resonant frequency to receive an external electromagnetic signal; the RF link includes a limiter, a low noise amplifier, the filter, and the mixer, and the local oscillator provides the signal source for the mixer, and the electromagnetic signal is filtered, amplified, and mixed to generate the intermediate frequency signal, which passes through the RF via and the strip line inside the printed circuit board to reach the feed port and then enters the baseband for data processing.

5. The compact miniaturized electrically adjustable AIP active antenna according to claim 2, characterized in that: The conversion formula of the digital-to-analog conversion chip is: Vout1=Vref*k / n; Among them, Vout1 is the output voltage, Vref is the reference voltage of the digital-to-analog conversion chip, k is the adjustment coefficient, and n is the denominator factor, which is used to determine the precision of voltage regulation.

6. The compact miniaturized electrically adjustable AIP active antenna according to claim 5, characterized in that: The relationship between the output voltage of the first operational amplifier and the first resistor and the second resistor is: Vout2=-Vout1*R2 / R1; Wherein, Vout2 is the output voltage of the first operational amplifier, Vout1 is the output voltage of the digital-to-analog conversion chip, R2 is the resistance value of the second resistor, and R1 is the resistance value of the first resistor; the output voltage of the second operational amplifier and the output voltage of the first operational amplifier are related to each other, Vout3=-Vout2; The output voltage after the emitter-follower circuit is: Vout3 = Vout1*R2 / R1.

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