CN212543741U

CN212543741U - High-performance duplexer based on SAW and BAW

Info

Publication number: CN212543741U
Application number: CN202021093030.9U
Authority: CN
Inventors: 胡孝伟; 代文亮; 马举
Original assignee: Shanghai Sinbo Electronic Technology Co ltd
Current assignee: Shanghai Sinbo Electronic Technology Co ltd
Priority date: 2020-06-15
Filing date: 2020-06-15
Publication date: 2021-02-12
Anticipated expiration: 2030-06-15

Abstract

The utility model discloses a high performance duplexer based on SAW and BAW belongs to duplexer technical field. The system comprises a first filter, namely a bulk acoustic wave filter BAW, for filtering a transmitted radio frequency signal and a second filter, namely a surface acoustic wave filter SAW, for receiving and filtering the radio frequency signal; by using the SAW resonator at the final stage of the first filter, the deterioration of the second order distortion and the harmonic characteristics can be suppressed. In addition, by incorporating the SAW resonator of the first filter in series with the SAW resonator of the second filter in the same SAW chip, antenna matching can be improved relative to other duplexers. Meanwhile, the loop is configured to generate an inverse signal with a target signal at a specific frequency to suppress the target signal, so that the stability and high out-of-band suppression of the duplexer are improved, and the size is reduced.

Description

High-performance duplexer based on SAW and BAW

Technical Field

The utility model belongs to the technical field of the duplexer, a high performance duplexer based on SAW and BAW particularly.

Background

Acoustic wave filters are widely used in radio frequency electronic systems. For example, the filter in the radio frequency front end of a mobile phone typically includes an acoustic wave filter, and two acoustic wave filters may be combined into one duplexer. The common duplexer is composed of a spiral vibration cavity, and because the working frequency is high and the influence of distribution parameters is large, the duplexer is often made into a sealing sleeve body, all signal feeder lines are coaxial cables with good shielding effect, and the shape and material of the cavity also require certain smoothness. In many LC duplexer circuit applications, a higher-order filter integrated design is required to meet design requirements, and as the design order of the filter is higher and higher, the accuracy requirements for the specifications of the components such as the inductor and the capacitor are also improved, so that the requirements are difficult to meet by applying the patch components with the existing specification and size.

The space available for wireless telephones, automobiles, etc. is limited, and wiring and heat dissipation of wireless telephones are also a concern, so that miniaturization of duplexers is highly desirable in order to meet other specifications.

SUMMERY OF THE UTILITY MODEL

1. Technical problem to be solved by the utility model

The utility model aims to solve the problem that the existing duplexer wants to realize indexes such as high outband suppression, high stability and the like and needs to adopt the filter integrated design of higher order level can lead to the volume too big, and the paster components and parts of the existing specification and size also hardly satisfy the demand simultaneously.

2. Technical scheme

In order to achieve the above purpose, the utility model provides a technical scheme does:

the utility model discloses a high performance duplexer based on SAW and BAW, include

A first filter, namely a bulk acoustic wave filter BAW, for filtering a transmitted radio frequency signal and a second filter, namely a surface acoustic wave filter SAW, for receiving and filtering the radio frequency signal;

the first filter comprises an S1 resonator, an S2 resonator, an S3 resonator, an S4 resonator and an RA1 resonator which are sequentially connected in series, wherein a P1 resonator and a P2 resonator are connected in parallel at two ends of the S1 resonator, a P3 resonator and a P4 resonator are connected in parallel at two ends of the S3 resonator, and an RA2 resonator is connected in parallel between the S4 resonator and the RA1 resonator;

the second filter comprises a B1 resonator, a B3 resonator, a B5 resonator, a B7 resonator and a B9 resonator which are sequentially connected in series, and the second filter further comprises: the B2 resonator connected between the B1 resonator and the B3 resonator, the B4 resonator connected between the B3 resonator and the B5 resonator, the B6 resonator connected between the B5 resonator and the B7 resonator, and the B8 resonator connected between the B7 resonator and the B9 resonator, wherein the B2 resonator, the B4 resonator, the B6 resonator and the B8 resonator are connected in parallel with one another.

Preferably, a first loop is connected to the first filter, the first loop and the first filter are connected through a capacitor, and the first loop is coupled to the input terminal S1 resonator and the output terminal RA1 resonator of the first filter.

Preferably, the second filter is further coupled with a second loop coupled to the input B1 resonator and the output B9 resonator of the second filter.

Preferably, the first loop circuit and the second loop circuit each comprise a plurality of SAW elements, the SAW elements being SAW resonators or SAW delay lines, each SAW element comprising an interdigital transducing electrode.

Preferably, the input end of the first filter is connected to a transmission signal input node TX.

Preferably, the output end of the second filter is connected to a receiving signal output node RX.

Preferably, an antenna port ANT is connected between the first filter and the second filter.

Preferably, the first loop circuit and the second loop circuit are configured to generate an inverse signal with respect to the target signal at a specific frequency to suppress the target signal, thereby improving out-of-band suppression and stability of the duplexer.

Preferably, an inductor TXL is connected in series between the transmission input node TX and the first filter.

Preferably, the last stage of the first filter uses SAW resonators by combining the series SAW resonator of the first filter with the SAW resonator of the first filter in the same SAW chip.

3. Advantageous effects

Adopt the technical scheme provided by the utility model, compare with prior art, have following beneficial effect:

the utility model discloses a high performance duplexer based on SAW and BAW for filter the first wave filter that launches radio frequency signal promptly bulk acoustic wave filter BAW and be used for receiving radio frequency signal and carry out the second wave filter that filters promptly table acoustic wave filter SAW; the first filter comprises an S1 resonator, an S2 resonator, an S3 resonator, an S4 resonator and an RA1 resonator which are sequentially connected in series, wherein a P1 resonator and a P2 resonator are connected in parallel at two ends of the S1 resonator, a P3 resonator and a P4 resonator are connected in parallel at two ends of the S3 resonator, and an RA2 resonator is connected in parallel between the S4 resonator and the RA1 resonator; the second filter comprises a B1 resonator, a B3 resonator, a B5 resonator, a B7 resonator and a B9 resonator which are sequentially connected in series, and further comprises: a B2 resonator connected between the B1 resonator and the B3 resonator, a B4 resonator connected between the B3 resonator and the B5 resonator, a B6 resonator connected between the B5 resonator and the B7 resonator, and a B8 resonator connected between the B7 resonator and the B9 resonator, with the B2 resonator, the B4 resonator, the B6 resonator, and the B8 resonator being connected in parallel with each other. By using the SAW resonator at the final stage of the first filter, the deterioration of the second order distortion and the harmonic characteristics can be suppressed. In addition, by incorporating the SAW resonator of the first filter in series with the SAW resonator of the second filter in the same SAW chip, antenna matching can be improved relative to other duplexers. Meanwhile, the loop is configured to generate an inverse signal with a target signal at a specific frequency to suppress the target signal, so that the stability and high out-of-band suppression of the duplexer are improved, and the size is reduced.

Drawings

Fig. 1 is a schematic structural diagram of a high-performance duplexer based on SAW and BAW according to the present invention.

Fig. 2 is a schematic diagram illustrating a coupling loop structure of a high performance duplexer based on SAW and BAW according to the present invention.

Detailed Description

In order to facilitate understanding of the invention, the invention will be described more fully hereinafter with reference to the accompanying drawings, in which several embodiments of the invention are shown, but which can be embodied in many different forms and are not limited to the embodiments described herein, but which are provided so as to render the disclosure of the invention more thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present; when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present; the terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

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 invention belongs; the terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention; as used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Example 1

Referring to fig. 1, a high performance duplexer based on SAW and BAW of the present embodiment includes a first filter, i.e., bulk acoustic wave filter BAW, for filtering a transmission rf signal and a second filter, i.e., surface acoustic wave filter SAW, for receiving and filtering the rf signal;

A duplexer is composed based on a highly integrated surface acoustic wave SAW filter and bulk acoustic wave BAW filter, and deterioration of secondary distortion and harmonic characteristics can be suppressed by using SAW resonators at the final stage of the first filter. Further antenna matching can be improved relative to other duplexers by incorporating the SAW resonator of the first filter in series with the SAW resonator of the second filter in the same SAW chip. Meanwhile, the loop is configured to generate an inverse signal with a target signal at a specific frequency to suppress the target signal, so that the stability and high out-of-band suppression of the duplexer are improved, and the size of the duplexer is reduced.

The first filter of this embodiment is connected with a first loop, and the first loop and the first filter are connected through a capacitor, and the first loop is coupled to the input terminal S1 resonator and the output terminal RA1 resonator of the first filter.

The second filter of the present embodiment is further coupled with a second loop circuit coupled to the input terminal B1 resonator and the output terminal B9 resonator of the second filter.

The first loop and the second loop of this embodiment each comprise a number of SAW elements, either SAW resonators or SAW delay lines, each comprising interdigital transducing electrodes.

The input end of the first filter of this embodiment is connected to a transmission signal input node TX.

The output terminal of the second filter of this embodiment is connected to a reception signal output node RX.

An antenna port ANT is connected between the first filter and the second filter in this embodiment.

The first loop and the second loop of the present embodiment are configured to generate an inverted signal with respect to the target signal at a specific frequency to suppress the target signal, improving out-of-band suppression and stability of the duplexer.

An inductor TXL is connected in series between the transmission input node TX and the first filter in this embodiment, so that input matching can be improved and return loss can be reduced.

The final stage of the first filter of the present embodiment uses the SAW resonators, and by incorporating the series SAW resonators of the first filter and the SAW resonators of the first filter in the same SAW chip, the final stage of the first filter using the SAW resonators can suppress the deterioration of the second order distortion and the harmonic characteristics. In addition, by incorporating the series SAW resonator of the first filter and the SAW resonator of the first filter in the same SAW chip, antenna matching can be improved relative to other duplexers.

The above-mentioned embodiments only express a certain implementation manner of the present invention, and the description thereof is specific and detailed, but not construed as limiting the scope of the present invention; it should be noted that, for those skilled in the art, without departing from the concept of the present invention, several variations and modifications can be made, which all fall within the protection scope of the present invention; therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A high-performance duplexer based on SAW and BAW is characterized in that: comprises that

2. A SAW and BAW based high performance duplexer as claimed in claim 1, wherein: the first filter is connected with a first loop, the first loop and the first filter are connected through capacitors, and the first loop is coupled to an input terminal S1 resonator and an output terminal RA1 resonator of the first filter.

3. A SAW and BAW based high performance duplexer as claimed in claim 1, wherein: the second filter is also coupled with a second loop coupled to the input B1 resonator and the output B9 resonator of the second filter.

4. A SAW and BAW based high performance duplexer as claimed in claim 2, wherein: the first loop circuit and the second loop circuit each comprise a number of SAW elements, the SAW elements being SAW resonators or SAW delay lines, each SAW element comprising an interdigital transducing electrode.

5. A SAW and BAW based high performance duplexer as claimed in claim 1, wherein: and the input end of the first filter is connected with a transmitting signal input node TX.

6. A SAW and BAW based high performance duplexer as claimed in claim 1, wherein: and the output end of the second filter is connected with a receiving signal output node RX.

7. A SAW and BAW based high performance duplexer as claimed in claim 1, wherein: an antenna port ANT is connected between the first filter and the second filter.

8. A SAW and BAW based high performance duplexer in accordance with claim 4, wherein: the first loop and the second loop are configured to generate an inverse signal with a target signal at a particular frequency to suppress the target signal, improving out-of-band rejection and duplexer stability.

9. A SAW and BAW based high performance duplexer in accordance with claim 5, wherein: an inductor TXL is connected in series between the transmission signal input node TX and the first filter.

10. A SAW and BAW based high performance duplexer in accordance with any one of claims 1 to 8, wherein: the last stage of the first filter uses SAW resonators by combining the series SAW resonators of the first filter with the SAW resonators of the first filter in the same SAW chip.