W-band miniaturized subharmonic mixer

Abstract

The utility model relates to a W-band miniaturized subharmonic mixer, which comprises a quartz substrate, a substrate circuit arranged on the quartz substrate, a radio frequency waveguide connected with the left side of the substrate circuit, a local oscillator waveguide connected with the middle part of the substrate circuit, and an intermediate frequency output end connected with the right side of the substrate circuit, the local oscillator low-pass filter sequentially comprises a plurality of first micro-strip parts from left to right, second micro-strip parts are arranged on the two sides of the first micro-strip parts and between every two adjacent first micro-strip parts, the first micro-strip parts are bent into rectangular structures with openings facing the left side or the right side, and the second micro-strip parts are bent into rectangular structures with openings facing the front side or the rear side. According to the utility model, the width and length of the microstrip substrate are reduced, the processing difficulty of the microstrip is reduced, the assembling difficulty is reduced, and the final volume of the mixer is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field related to millimeter wave communication equipment and accessories used therein, and in particular to a W-band miniaturized subharmonic mixer. Background Art

[0002] Millimeter wave and terahertz transceiver front-end is widely used in almost all millimeter wave and terahertz application systems such as communications and radars. It is used to solve the problem of signal frequency conversion and is the core part of the entire system. It is mainly composed of key components such as mixers, filters and amplifiers.

[0003] After massive searches, it was found that the prior art publication number is CN213186048U, which discloses a W-band subharmonic mixer, including a radio frequency waveguide, a microstrip transmission cavity connected to the radio frequency waveguide, and a local oscillator waveguide connected to the microstrip transmission cavity, wherein a mixing circuit structure is arranged in the microstrip transmission cavity; the mixing circuit structure includes a radio frequency probe, a local oscillator low-pass filter, a local oscillator probe and an intermediate frequency low-pass filter connected in series by a microstrip line, and a Schottky diode installed on the microstrip line in the forward direction; the radio frequency probe is opposite to the radio frequency waveguide, and the local oscillator probe is opposite to the local oscillator waveguide. The subharmonic mixer circuit is planar, simple in structure, easy to assemble, and has low frequency conversion loss, wide intermediate frequency bandwidth, and high isolation between radio frequency and local oscillator.

[0004] In summary, the W-band subharmonic mixer has similar performance to other balanced mixers, but its local oscillator frequency is much lower than the frequency required by the balanced mixer, and its requirement for local oscillator power is also low, which reduces the difficulty of designing and manufacturing the local oscillator source. Therefore, it is widely used in W-band radar and communication transceiver systems. The mixer involves the design of intermediate frequency low-pass filter, local oscillator low-pass filter, RF local oscillator probe and matching network, resulting in a long length of the final mixer microstrip. The terahertz mixer microstrip uses thin and brittle quartz as the dielectric substrate, which greatly increases the difficulty and cost of processing. While ensuring good mixer performance, it is necessary to reduce the volume of the mixer and the difficulty of processing the microstrip, and design a small volume microstrip.

[0005] In view of the above-mentioned defects, the designers have actively carried out research and innovation in order to create a W-band miniaturized sub-harmonic mixer to make it more valuable for industrial use. Utility Model Content

[0006] To solve any of the above technical problems, the purpose of the present utility model is to provide a W-band miniaturized subharmonic mixer.

[0007] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0008] A W-band miniaturized subharmonic mixer comprises a quartz substrate, on which a substrate circuit is arranged, a radio frequency waveguide connected to the left side of the substrate circuit, a local oscillator waveguide connected to the middle of the substrate circuit, and an intermediate frequency output terminal connected to the right side of the substrate circuit, wherein the substrate circuit comprises a radio frequency probe, a local oscillator low-pass filter, a local oscillator probe and an intermediate frequency low-pass filter connected in sequence from left to right by a plurality of microstrip lines, the radio frequency probe is opposite to the radio frequency waveguide, and the local oscillator probe is opposite to the local oscillator waveguide;

[0009] The local oscillator low-pass filter includes several first microstrip portions from left to right, and second microstrip portions are arranged on both sides of the first microstrip portions and between two adjacent first microstrip portions. The first microstrip portion is bent into a rectangular structure opening toward the left side or the right side, and the second microstrip portion is bent into a rectangular structure opening toward the front side or the rear side.

[0010] As a further improvement of the present invention, the opening directions of the plurality of first microstrip portions are consistent, staggered, or randomly distributed.

[0011] As a further improvement of the present invention, the opening directions of the plurality of second microstrip portions are consistent, staggered, or randomly distributed.

[0012] As a further improvement of the utility model, a Schottky diode is installed in the forward direction on the microstrip line of the substrate circuit, and the Schottky diode is located at one end of the radio frequency probe.

[0013] As a further improvement of the present invention, the thickness of the quartz substrate is 127 um.

[0014] As a further improvement of the utility model, both the local oscillator low-pass filter and the intermediate frequency low-pass filter adopt high-low impedance microstrip.

[0015] By means of the above solution, the utility model has at least the following advantages:

[0016] The utility model reduces the width and length of the microstrip substrate, reduces the processing difficulty of the microstrip, reduces the assembly difficulty, and reduces the volume of the final mixer.

[0017] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the utility model in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model 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 creative work.

[0019] Figure 1 It is a structural schematic diagram of the prior art;

[0020] Figure 2 yes Figure 1 A schematic diagram of the local enlarged structure at point A in the middle;

[0021] Figure 3 yes Figure 2 Schematic diagram of the improvement in the present invention.

[0022] The meanings of the various reference numerals in the figures are as follows.

[0023] RF waveguide 1, local oscillator waveguide 2, quartz substrate 3, RF probe 4, Schottky diode 5, local oscillator low-pass filter 6, local oscillator probe 7, intermediate frequency low-pass filter 8, intermediate frequency output end 9, first microstrip portion 10, second microstrip portion 11. DETAILED DESCRIPTION

[0024] The following is a further detailed description of the specific implementation of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0025] In order to make the technical personnel in the technical field better understand the scheme of the utility model, the technical scheme in the embodiment of the utility model will be clearly and completely described below in combination with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, rather than all the embodiments. The components of the embodiment of the utility model usually described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the utility model provided in the drawings is not intended to limit the scope of the utility model for protection, but only represents the selected embodiment of the utility model. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the utility model.

[0026] Example

[0027] like Figure 1 to Figure 3 As shown,

[0028] A W-band miniaturized subharmonic mixer includes a quartz substrate 3, the thickness of which is 127 um. A substrate circuit, a radio frequency waveguide 1 connected to the left side of the substrate circuit, a local oscillator waveguide 2 connected to the middle of the substrate circuit, and an intermediate frequency output terminal 9 connected to the right side of the substrate circuit are arranged on the quartz substrate 3. The substrate circuit includes a radio frequency probe 4, a local oscillator low-pass filter 6, a local oscillator probe 7, and an intermediate frequency low-pass filter 8 connected in sequence from left to right by a plurality of microstrip lines. The radio frequency probe 4 is opposite to the radio frequency waveguide 1, and the local oscillator probe 7 is opposite to the local oscillator waveguide 2. A Schottky diode 5 is forwardly installed on the microstrip line of the substrate circuit, and the Schottky diode 5 is located at one end of the radio frequency probe 4.

[0029] The local oscillator low-pass filter 6 and the intermediate frequency low-pass filter 8 mentioned above are both high-low impedance microstrips.

[0030] The local oscillator low-pass filter 6 includes a plurality of first microstrip portions 10 in sequence from left to right. Second microstrip portions 11 are provided on both sides of the first microstrip portions 10 and between two adjacent first microstrip portions 10 .

[0031] The first microstrip portions 10 in the prior art are all distributed along the front-to-back direction, and the second microstrip portions 11 in the prior art are all distributed along the left-to-right direction.

[0032] like Figure 3 The technical problem to be solved by the utility model is to reduce the difficulty of microstrip processing and assembly, and to design a subharmonic mixer with a smaller size while meeting the performance of the subharmonic mixer. Therefore, a bending design is performed in the first microstrip portion 10 and the second microstrip portion 11.

[0033] The first microstrip portion 10 is bent into a rectangular structure that is open toward the left or right side, and the opening directions of a plurality of first microstrip portions 10 are consistent, staggered, or randomly distributed.

[0034] The second microstrip portion 11 is bent into a rectangular structure that is open toward the front or rear side, and the opening directions of a plurality of second microstrip portions 11 are consistent, staggered, or randomly distributed.

[0035] The local oscillator low-pass filter in the subharmonic of the utility model is implemented by a high-low impedance microstrip. In order to obtain a better filtering effect, the low-pass filter will be wide and long. Without affecting the performance, the wider capacitive microstrip (i.e., the first microstrip portion 10) is bent, and the longer inductive microstrip (i.e., the second microstrip portion 11) is bent to achieve the purpose of reducing the width and length of the microstrip.

[0036] The utility model reduces the length and width of the microstrip substrate of the subharmonic mixer to achieve the purpose of reducing the processing and assembly difficulty of the microstrip and the cavity.

[0037] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implying the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0038] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, it can be a mechanical connection, it can be an electrical connection, it can be a direct connection, it can be an indirect connection through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the technical principle of the present invention, and these improvements and modifications should also be regarded as within the protection scope of the present invention.

Claims

1. A W-band miniaturized subharmonic mixer, comprising a quartz substrate (3), on which a substrate circuit is arranged, a radio frequency waveguide (1) connected to the left side of the substrate circuit, a local oscillator waveguide (2) connected to the middle of the substrate circuit, and an intermediate frequency output terminal (9) connected to the right side of the substrate circuit, wherein the substrate circuit comprises a radio frequency probe (4), a local oscillator low-pass filter (6), a local oscillator probe (7), and an intermediate frequency low-pass filter (8) connected in sequence from left to right by a plurality of microstrip lines, wherein the radio frequency probe (4) is opposite to the radio frequency waveguide (1), and the local oscillator probe (7) is opposite to the local oscillator waveguide (2); Features: The local oscillator low-pass filter (6) comprises a plurality of first microstrip portions (10) in sequence from left to right, a second microstrip portion (11) being arranged on both sides of the first microstrip portion (10) and between two adjacent first microstrip portions (10), the first microstrip portion (10) being bent into a rectangular structure opening toward the left side or the right side, and the second microstrip portion (11) being bent into a rectangular structure opening toward the front side or the rear side.

2. A W-band miniaturized subharmonic mixer as claimed in claim 1, characterized in that: The opening directions of a plurality of the first microstrip portions (10) are all consistent or arranged in a staggered distribution or in a random distribution.

3. A W-band miniaturized subharmonic mixer as claimed in claim 1, characterized in that: The opening directions of a plurality of the second microstrip portions (11) are all consistent or arranged in a staggered distribution or in a random distribution.

4. A W-band miniaturized subharmonic mixer as claimed in claim 1, characterized in that: A Schottky diode (5) is mounted in the forward direction on the microstrip line of the substrate circuit, and the Schottky diode (5) is located at one end of the radio frequency probe (4).

5. A W-band miniaturized subharmonic mixer as claimed in claim 1, characterized in that: The thickness of the quartz substrate (3) is 127 um.

6. A W-band miniaturized subharmonic mixer as claimed in claim 1, characterized in that: The local oscillator low-pass filter (6) and the intermediate frequency low-pass filter (8) both adopt high-low impedance microstrip.

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