CN107332516A - One kind is based on the passive double balanced mixer of multilayer Marchand microstrip baluns - Google Patents

Abstract

The invention discloses a passive double-balanced mixer based on a multilayer Marchand microstrip balun, which is realized on a two-layer laminated insulating dielectric substrate; the passive double-balanced mixer based on a multilayer Marchand microstrip balun The device includes a bridge mixing unit composed of a radio frequency microstrip balun, a local oscillator microstrip balun and four mixing diodes; the radio frequency microstrip balun and the local oscillator microstrip balun are Marchand microstrip baluns; The input end of the radio frequency microstrip balun is set as the input end of the passive double-balanced mixer, which is connected to the radio frequency signal; the input end of the local oscillator microstrip balun is connected to the local oscillator signal, and the output end of the radio frequency microstrip balun and the output end of the local oscillator microstrip balun are respectively connected to the input end of the bridge mixing unit; the output end of the passive double-balanced mixer is an intermediate frequency output port formed by coupling based on the local oscillator microstrip balun; the bridge The input and output ends of the type mixing unit and the passive double-balanced mixer are all arranged on the same plane.

Description

A passive double-balanced mixer based on multilayer Marchand microstrip balun

technical field

The invention belongs to the field of mixers, in particular to a passive double-balanced mixer based on a multilayer Marchand microstrip balun.

Background technique

Microwave and millimeter wave mixers are widely used in electronic testing, communication, radar, electronic countermeasures and other systems. Its function is used for frequency conversion of signals. As a frequency conversion circuit, the mixer is used according to the type of nonlinear device used. Can be divided into active mixer and passive mixer. Passive mixers use diodes as nonlinear devices, which are characterized by simple circuits, easy design, easy integration, stable operation, and good performance. Passive mixers are divided into single-ended mixers and balanced mixers according to different circuit structures. Passive, double-balanced mixer is a balanced circuit composed of two, four or more mixing diodes with the same characteristics, and the circuit is mostly composed of balanced balun interconnections, which have low noise, high sensitivity, It has the advantages of strong anti-interference ability and wide frequency bandwidth.

Passive, double-balanced mixer, usually composed of a balanced diode pair, 180 ⁰ 3dB choke coil (balun) and an intermediate frequency low-pass filter, the current broadband balun design mainly uses progressive double-sided lines, its 180 ⁰ phase The two poor outputs are on the upper and lower planes respectively, and the diode pair pads are generally on the same plane, so the connection between the balun and the diode pair is a three-dimensional structure, so high requirements are placed on the welding process. At the same time, there are The poor continuity of signal transmission affects the performance of the mixer. For the ^balun in the form of power division, although the two outputs with a phase difference of 1800 are on the same plane, there are usually disadvantages of relatively narrow bandwidth and relatively large manufacturing size. Similarly, although the microstrip balun with two-wire coupling can reduce the size of the device and realize ultra-wideband, the straddling interconnection structure of the microstrip balun seriously affects the performance of the device and is not suitable for higher frequencies.

Contents of the invention

In order to solve the deficiencies of the prior art, the present invention provides a passive double-balanced mixer based on a multilayer Marchand microstrip balun, which realizes signal conversion from unbalanced to balanced through the conversion of multilayer microstrip circuits. The two ^outputs with a phase difference of 1800 are in the same plane, and the practical frequency range is wide, and the balun itself has high-pass transmission characteristics, which improves the isolation performance of the mixer local oscillator and RF port to the IF port.

A kind of passive double-balanced mixer based on multilayer Marchand microstrip balun of the present invention, it realizes on the insulating dielectric substrate of two-layer lamination; Said based on multilayer Marchand microstrip balun passive double-balanced mixer A bridge mixing unit comprising a radio frequency microstrip balun, a local oscillator microstrip balun and four mixing diodes; the radio frequency microstrip balun and the local oscillator microstrip balun are both Marchand microstrip baluns;

The input end of the radio frequency microstrip balun is set as the input end of the passive double-balanced mixer, which is connected to the radio frequency signal; the input end of the local oscillator microstrip balun is connected to the local oscillator signal, and the output end of the radio frequency microstrip balun and the output end of the local oscillator microstrip balun are respectively connected to the input end of the bridge mixing unit; the output end of the passive double-balanced mixer is an intermediate frequency output port formed by coupling based on the local oscillator microstrip balun; the bridge The input and output ends of the type mixing unit and the passive double-balanced mixer are all arranged on the same plane.

Further, the two laminated insulating dielectric substrates are directly connected to each other through the corresponding metal holes on the respective substrates, so as to realize the conversion of the microstrip line.

The circuit of the invention is simple to manufacture and small in size, realizes circuit interconnection and grounding through metallized holes, avoids interference between signals in traditional metal connection lines, and improves signal frequency range.

Further, the insulating dielectric substrate of the lowest layer among the two laminated insulating dielectric substrates is an alumina substrate whose dielectric substrate material is more than 99.6% pure.

It should be noted that the two-layer laminated insulating dielectric substrate is selected according to the impedance matching principle in the actual circuit requirements. The lowest insulating dielectric substrate is one of the aluminum oxide substrates whose dielectric substrate material is more than 99.6% pure. In addition, the dielectric substrate material can also be an aluminum nitride substrate with a purity of 98%.

Wherein, the thickness of the bottom insulating dielectric substrate is 0.1mm-0.5mm.

Further, the uppermost insulating dielectric substrate among the two laminated insulating dielectric substrates is a polyimide substrate whose dielectric substrate material has a purity of more than 99%.

It should be noted that the two-layer laminated insulating dielectric substrate is selected according to the impedance matching principle in the actual circuit requirements. The uppermost layer of insulating dielectric substrate is polyimide base material with a purity of more than 99%. A substrate of other materials can also be selected according to the actual situation.

Wherein, the thickness of the uppermost insulating dielectric substrate is 0.01mm-0.15mm.

Further, the RF microstrip balun and the local oscillator microstrip balun are respectively connected to the bridge mixing unit by flip-chip soldering.

This ensures that the bonding pads of the mixing diodes in the bridge mixing unit are in the same plane structure.

Further, the passive double-balanced mixer based on multilayer Marchand microstrip balun is applied to a single plane circuit.

Further, the passive double-balanced mixer based on the multilayer Marchand microstrip balun is mounted in the cavity.

Compared with prior art, the beneficial effect of the present invention is:

(1) The multi-layer Marchand microstrip balun passive double-balanced mixer of the present invention realizes signal conversion from unbalanced to balanced by applying the conversion of multi-layered microstrip circuits. The two ^outputs with a phase difference of 1800 are in the same plane, and the practical frequency range is wide, and the balun itself has high-pass transmission characteristics, which improves the isolation performance of the mixer local oscillator and RF port to the IF port.

(2) The passive double-balanced mixer based on the multi-layer Marchand microstrip balun of the present invention has wide applicable frequency, simple circuit fabrication, and is easy to realize by using traditional microwave production technology. At the same time, the same dielectric material is used to realize the small volume of the circuit.

(3) The passive double-balanced mixer based on the multi-layer Marchand microstrip balun of the present invention can realize the conversion of microwave transmission from unbalanced to balanced state. The structure can be applied to lower frequency applications, and the structure size can also be changed according to different frequencies, but the structure principle remains the same.

Description of drawings

The accompanying drawings constituting a part of the present application are used to provide further understanding of the present application, and the schematic embodiments and descriptions of the present application are used to explain the present application, and do not constitute improper limitations to the present application.

Fig. 1 is a circuit diagram based on a multilayer Marchand microstrip balun passive double-balanced mixer;

Fig. 2 is a two-layer laminated insulating dielectric substrate based on a multilayer Marchand microstrip balun passive double-balanced mixer;

Fig. 3 is the schematic diagram of the circuit structure of the aluminum oxide substrate front side of the present invention;

Fig. 4 is the reverse schematic diagram of alumina substrate of the present invention;

Fig. 5 is a schematic diagram of the circuit structure of the front side of the polyimide substrate;

Fig. 6 is the reverse schematic diagram of polyimide substrate;

Fig. 7 is a schematic structural diagram of a bridge mixing unit.

Among them, 1. The input terminal of the RF microstrip balun; 2. The first output terminal of the bridge mixing unit; 3. The second output terminal of the bridge mixing unit; 4. The input terminal of the local oscillator microstrip balun ; 5, the first input end of the bridge type mixing unit; 6, the second input end of the bridge type frequency mixing unit; 7, the intermediate frequency output port; 8, the metal through hole on the alumina substrate; 9, polyimide Metal vias on the substrate; 10. Local oscillator microstrip balun; 11. RF microstrip balun.

detailed description

It should be pointed out that the following detailed description is exemplary and intended to provide further explanation to the present application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It should be noted that the terminology used here is only used to describe specific implementations, and is not intended to limit the exemplary implementations according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural, and it should also be understood that when the terms "comprising" and/or "comprising" are used in this specification, they mean There are features, steps, operations, means, components and/or combinations thereof.

As shown in FIG. 2, a passive double-balanced mixer based on a multilayer Marchand microstrip balun of the present invention is implemented on a two-layer laminated insulating dielectric substrate.

As shown in Figure 1, the passive double-balanced mixer based on the multilayer Marchand microstrip balun of the present invention comprises a bridge type mixer composed of a radio frequency microstrip balun 11, a local oscillator microstrip balun 10 and four mixing diodes. frequency unit; the radio frequency microstrip balun and the local oscillator microstrip balun are both Marchand microstrip baluns.

The input terminal 1 of the radio frequency microstrip balun is set as the input terminal of the passive double-balanced mixer, which is connected to the radio frequency signal; the input terminal 4 of the local oscillator microstrip balun is connected to the local oscillator signal, and the input terminal 4 of the radio frequency microstrip balun is connected to the local oscillator signal. The output terminal and the output terminal of the local oscillator microstrip balun are respectively connected to the input terminal of the bridge mixing unit; the output terminal of the passive double-balanced mixer is an intermediate frequency output formed by coupling based on the local oscillator microstrip balun 10 Terminal 7; the input and output terminals of the bridge mixing unit and the passive double-balanced mixer are all arranged on the same plane.

Wherein, the two laminated insulating dielectric substrates are directly connected to each other through corresponding metal holes on the respective substrates, so as to realize the conversion of the microstrip line.

The circuit of the invention is simple to manufacture and small in size, realizes circuit interconnection and grounding through metallized holes, avoids interference between signals in traditional metal connection lines, and improves signal frequency range.

In this embodiment, the insulating dielectric substrate of the lowest layer among the two laminated insulating dielectric substrates is an alumina substrate whose dielectric substrate material has a purity of more than 99.6%.

It should be noted that the two-layer laminated insulating dielectric substrate is selected according to the impedance matching principle in the actual circuit requirements. The lowest insulating dielectric substrate is one of the aluminum oxide substrates whose dielectric substrate material is more than 99.6% pure. In addition, the dielectric substrate material can also be an aluminum nitride substrate with a purity of 98%.

Wherein, the thickness of the bottom insulating dielectric substrate is 0.1mm-0.5mm.

As shown in Figure 3, the second output end 3 of the bridge type frequency mixing unit, the second input end 6 of the bridge type frequency mixing unit, the input end 4 of the local oscillator microstrip balun, the first output of the bridge type frequency mixing unit The terminal 2, the first input terminal 5 of the bridge-type mixing unit, and the metal through hole 8 on the alumina substrate are all arranged on the front surface of the alumina substrate, and their connection relationship is shown in FIG. 1 .

As shown in FIG. 4, the metal vias 8 on the alumina substrate are all gold-plated holes.

Wherein, the uppermost insulating dielectric substrate in the two-layer laminated insulating dielectric substrate is a polyimide substrate whose dielectric substrate material is more than 99% pure.

As shown in Fig. 5 and Fig. 6: 9 is a metallized hole, and the circuit on the polyimide substrate is connected with the circuit on the alumina substrate through the metal through hole.

The uppermost insulating dielectric substrate has a thickness of 0.01 mm to 0.15 mm.

It should be noted that the two-layer laminated insulating dielectric substrate is selected according to the impedance matching principle in the actual circuit requirements. The uppermost layer of insulating dielectric substrate is polyimide base material with a purity of more than 99%. A substrate of other materials can also be selected according to the actual situation.

Wherein, as shown in FIG. 7 , the RF microstrip balun and the local oscillator microstrip balun are respectively connected to the bridge mixing unit by flip-chip soldering. Specifically, the second output terminal 3 of the bridge mixing unit, the second input terminal 6 of the bridge mixing unit, the first output terminal 2 of the bridge mixing unit, and the first input terminal 5 of the bridge mixing unit connected by flip-chip soldering,

This ensures that the bonding pads of the mixing diodes in the bridge mixing unit are in the same plane structure.

Specifically, the passive double-balanced mixer based on the multilayer Marchand microstrip balun is applied to a single plane circuit.

Specifically, the passive double-balanced mixer based on the multi-layer Marchand microstrip balun of the present invention is mounted in the cavity.

The multi-layer Marchand microstrip balun passive double-balanced mixer of the present invention has a local oscillator/radio frequency application frequency range of 10GHz-50Ghz, an intermediate frequency frequency range of DC-10GHz, and a typical value of fundamental frequency conversion loss of 10dB.

The passive double-balanced mixer based on the multi-layer Marchand microstrip balun of the present invention has wide applicable frequency, simple circuit manufacture, and is easy to realize by using traditional microwave production technology. At the same time, the same dielectric material is used to realize the small volume of the circuit.

The multi-layer Marchand microstrip balun passive double-balanced mixer of the present invention can realize the conversion of microwave transmission from unbalanced state to balanced state. The structure can be applied to lower frequency applications, and the structure size can also be changed according to different frequencies, but the structure principle remains the same.

Although the specific implementation of the present invention has been described above in conjunction with the accompanying drawings, it does not limit the protection scope of the present invention. Those skilled in the art should understand that on the basis of the technical solution of the present invention, those skilled in the art do not need to pay creative work Various modifications or variations that can be made are still within the protection scope of the present invention.

Claims (10)

1. one kind is based on the passive double balanced mixer of multilayer Marchand microstrip baluns, it is characterised in that what it was overlapped at two layers Realized on dielectric substrate；It is described that radio frequency microstrip bar is included based on the passive double balanced mixer of multilayer Marchand microstrip baluns The bridge-type mixing unit of human relations, local oscillator microstrip balun and four mixer diode compositions；The radio frequency microstrip balun and local oscillator micro-strip Balun is Marchand microstrip baluns；

The input of radio frequency microstrip balun is set to the input of the passive double balanced mixer, and it connects radiofrequency signal；This Shake the input connection local oscillation signal of microstrip balun, the output end difference of the output end of radio frequency microstrip balun and local oscillator microstrip balun It is connected to the input of bridge-type mixing unit；The output end of passive double balanced mixer is to be coupled based on local oscillator microstrip balun The medium frequency output end mouthful of formation；The input and output end of bridge-type mixing unit and passive double balanced mixer are arranged at together In one plane.

2. as claimed in claim 1 a kind of based on the passive double balanced mixer of multilayer Marchand microstrip baluns, its feature exists In the dielectric substrate of two layers of overlapping is directly conducted by the metal aperture on corresponding respective substrate, realizes microstrip line Conversion.

3. as claimed in claim 1 a kind of based on the passive double balanced mixer of multilayer Marchand microstrip baluns, its feature exists In the orlop dielectric substrate in the dielectric substrate of two layers of overlapping is that dielectric substrate material is purity more than 99.6% Alumina substrate.

4. as claimed in claim 1 a kind of based on the passive double balanced mixer of multilayer Marchand microstrip baluns, its feature exists In the orlop dielectric substrate in the dielectric substrate of two layers of overlapping is the nitridation that dielectric substrate material is purity 98% Aluminium substrate.

5. one kind as described in claim 3 or 4 is based on the passive double balanced mixer of multilayer Marchand microstrip baluns, its feature It is, the thickness of orlop dielectric substrate is 0.1mm~0.5mm.

6. one kind as described in claim 3 or 4 is based on the passive double balanced mixer of multilayer Marchand microstrip baluns, its feature It is, the superiors' dielectric substrate in the dielectric substrate of two layers of overlapping is that dielectric substrate material is purity more than 99% Polyimide base film.

7. as claimed in claim 6 a kind of based on the passive double balanced mixer of multilayer Marchand microstrip baluns, its feature exists In the thickness of the superiors' dielectric substrate is 0.01mm~0.15mm.

8. as claimed in claim 1 a kind of based on the passive double balanced mixer of multilayer Marchand microstrip baluns, its feature exists In the radio frequency microstrip balun and local oscillator microstrip balun connect bridge-type mixing unit by upside-down mounting soldering respectively.

9. as claimed in claim 1 a kind of based on the passive double balanced mixer of multilayer Marchand microstrip baluns, its feature exists In described to be applied to single plane circuit based on the passive double balanced mixer of multilayer Marchand microstrip baluns.

10. as claimed in claim 1 a kind of based on the passive double balanced mixer of multilayer Marchand microstrip baluns, its feature exists In described to be mounted on based on the passive double balanced mixer of multilayer Marchand microstrip baluns in cavity.