CN212543743U

CN212543743U - Acoustic wave filter based on SAW-BAW technology combined application

Info

Publication number: CN212543743U
Application number: CN202021555993.6U
Authority: CN
Inventors: 胡孝伟; 代文亮; 赵瑞洁
Original assignee: Shanghai Sinbo Electronic Technology Co ltd
Current assignee: Shanghai Sinbo Electronic Technology Co ltd
Priority date: 2020-07-31
Filing date: 2020-07-31
Publication date: 2021-02-12
Anticipated expiration: 2030-07-31

Abstract

The utility model discloses an acoustic wave filter based on SAW-BAW technique combination is used, include TX1 port, RX1 port, TX2 port and RX2 port be connected with the COM port respectively, TX1 port, RX1 port, TX2 port, RX2 port all connect in parallel with the COM port through different filter branches, the filter branch road of TX1 port, RX1 port, TX2 port, RX2 port all includes a plurality of SAW syntonizer and a plurality of BAW syntonizer, realizes acoustic wave filter through using most SAW syntonizers, has reduced the volume, has practiced thrift the cost and has improved the effect.

Description

Acoustic wave filter based on SAW-BAW technology combined application

Technical Field

The utility model belongs to the technical field of the wave filter, be an acoustic wave filter based on SAW-BAW technology combination is used particularly.

Background

In radio frequency filters, an important characteristic is the steepness of the transition band, i.e. the curve between the pass band and the stop band in the band pass characteristic of the filter. The transition bandwidth between the pass band and the stop band, if too narrow, can greatly increase the design difficulty of the filter. In order to improve the steepness of the transition band, the design of the connection circuit between the resonators constituting the filter is important, but the characteristics (quality factor or Q value) of the resonance unit itself are also critical factors. In order to meet the filter design requirements of these high-difficulty frequency bands, the Q value of the resonant unit needs to be increased.

SAW devices have been widely used in radio frequency filters having interdigital transducers mounted on the surface of a piezoelectric substrate. The resonance characteristics of the surface acoustic wave excited by the IDT determine the characteristic frequency band of the RF filter

The BAW filter has high sound energy density, and the structure can well guide and limit sound waves and has very low loss. At microwave frequencies, BAW achievable Q values, at comparable volumes, are higher than any other type of filter, and can be: 2500@2 GHz. This results in excellent rejection and insertion loss performance even at the tight edges of the passband. The BAW filter also shrinks in size with increasing frequency, which makes it very suitable for very demanding 4G, 5G applications. Furthermore, even in high bandwidth designs, BAWs are less sensitive to temperature variations, while they also have very low losses and very steep filter skirts.

However, the existing technology is difficult to reduce the whole volume of the filter and improve the performance of the filter.

SUMMERY OF THE UTILITY MODEL

1. Technical problem to be solved by the utility model

An object of the utility model is to solve the problem that current technique is difficult to fine reduction wave filter holistic volume and improves the performance of wave filter.

2. Technical scheme

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

the utility model discloses an acoustic wave filter based on SAW-BAW technique combination is used, include TX1 port, RX1 port, TX2 port and RX2 port be connected with the COM port respectively, TX1 port, RX1 port, TX2 port, RX2 port all connect in parallel with the COM port through different filter branches, the filter branch road of TX1 port, RX1 port, TX2 port, RX2 port all includes a plurality of SAW syntonizer and a plurality of BAW syntonizer.

Preferably, the filter branch circuit connected with the TX1 port and the COM port comprises a first SAW resonator, a second SAW resonator and a first BAW resonator which are sequentially connected in series, a third SAW resonator is connected between the first SAW resonator and the second SAW resonator in parallel, a fourth SAW resonator is connected between the second SAW resonator and the first BAW resonator in parallel, and one end of each of the third SAW resonator and the fourth SAW resonator is grounded.

Preferably, the filter branch circuit connected with the RX1 port and the COM port includes a SAW resonator five, a SAW resonator six and a BAW resonator two connected in series in sequence, the SAW resonator seven is connected in parallel between the SAW resonator five and the SAW resonator six, the SAW resonator eight is connected in parallel between the SAW resonator six and the BAW resonator two, and one end of each of the SAW resonator seven and the SAW resonator eight is grounded.

Preferably, the filter branch circuit connected with the TX2 port and the COM port comprises a SAW resonator nine, a SAW resonator ten and a BAW resonator three which are sequentially connected in series, the SAW resonator eleven is connected in parallel between the TX2 port and the SAW resonator nine, the SAW resonator twelve is connected in parallel between the SAW resonator nine and the SAW resonator eleven, the SAW resonator thirteen is connected in parallel between the SAW resonator eleven and the BAW resonator three, the BAW resonator four is connected in parallel between the BAW resonator three and the COM port, and one end of each of the SAW resonator eleven, the SAW resonator twelve, the SAW resonator thirteen and the BAW resonator four is grounded.

Preferably, the filter branch circuit connected with the RX2 port and the COM port comprises a SAW resonator fourteen, a SAW resonator fifteen and a BAW resonator five which are sequentially connected in series, the SAW resonator sixteen is connected between the RX2 port and the SAW resonator fourteen in parallel, the SAW resonator seventeen is connected between the SAW resonator fourteen and the SAW resonator fifteen in parallel, the SAW resonator eighteen is connected between the SAW resonator fifteen and the BAW resonator fifty in parallel, and one end of each of the SAW resonator sixteen, the SAW resonator seventeen and the SAW resonator eighteen is grounded.

3. Advantageous effects

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

the utility model discloses an acoustic wave filter based on SAW-BAW technique combination is used, include TX1 port, RX1 port, TX2 port and RX2 port be connected with the COM port respectively, TX1 port, RX1 port, TX2 port, RX2 port all parallelly connected with the COM port through different filter branches, the filter branch road of TX1 port, RX1 port, TX2 port, RX2 port all includes a plurality of SAW syntonizer and a plurality of BAW syntonizer, realizes acoustic wave filter through using most SAW syntonizers, has reduced the volume, has practiced thrift the cost and has improved the effect.

Drawings

Fig. 1 is a schematic structural diagram of an acoustic wave filter based on combined application of SAW-BAW technologies 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, the acoustic wave filter based on combined application of SAW-BAW technology of this embodiment is characterized in that: the system comprises a TX1 port, an RX1 port, a TX2 port and an RX2 port which are respectively connected with a COM port, wherein the TX1 port, the RX1 port, the TX2 port and the RX2 port are all connected with the COM port in parallel through different filter branches, and the filter branches of the TX1 port, the RX1 port, the TX2 port and the RX2 port all comprise a plurality of SAW resonators and a plurality of BAW resonators.

The filter branch circuit with the TX1 port connected with the COM port comprises a SAW resonator I21, a SAW resonator II 23 and a BAW resonator I25 which are sequentially connected in series, a SAW resonator III 22 is connected between the SAW resonator I21 and the SAW resonator II 23 in parallel, a SAW resonator IV 24 is connected between the SAW resonator II 23 and the BAW resonator I25 in parallel, and one end of each of the SAW resonator III 22 and the SAW resonator IV 24 is grounded.

The filter branch circuit with the RX1 port connected with the COM port comprises a SAW resonator five 31, a SAW resonator six 33 and a BAW resonator two 36 which are sequentially connected in series, a SAW resonator seven 32 is connected between the SAW resonator five 31 and the SAW resonator six 33 in parallel, a SAW resonator eight 34 is connected between the SAW resonator six 33 and the BAW resonator two 36 in parallel, and one end of each of the SAW resonator seven 32 and the SAW resonator eight 34 is grounded.

The filter branch circuit with the TX2 port connected with the COM port comprises a SAW resonator nine 41, a SAW resonator ten 43 and a BAW resonator three 46 which are sequentially connected in series, a SAW resonator eleven 45 is connected between the TX2 port and the SAW resonator nine 41 in parallel, a SAW resonator twelve 42 is connected between the SAW resonator nine 41 and the SAW resonator ten 43 in parallel, a SAW resonator thirteen 44 is connected between the SAW resonator ten 43 and the BAW resonator three 46 in parallel, a BAW resonator four 47 is connected between the BAW resonator three 46 and the COM port in parallel, and one end of each of the SAW resonator eleven 45, the SAW resonator twelve 42, the SAW resonator thirteen 44 and the BAW resonator four 47 is grounded.

The filter branch circuit connected with the RX2 port and the COM port comprises a SAW resonator fourteen 51, a SAW resonator fifteen 53 and a BAW resonator five 56 which are sequentially connected in series, a SAW resonator sixteen 55 is connected between the RX2 port and the SAW resonator fourteen 51 in parallel, a SAW resonator seventeen 52 is connected between the SAW resonator fourteen 51 and the SAW resonator fifteen 53 in parallel, a SAW resonator eighteen 54 is connected between the SAW resonator fifteen 53 and the BAW resonator five 56 in parallel, and one end of each of the SAW resonator sixteen 55, the SAW resonator seventeen 52 and the SAW resonator eighteen 54 is grounded.

The series SAW resonators in the acoustic wave filter may be coupled to a common node of the quadplexer through the series BAW resonators. The series SAW resonator and the parallel SAW resonator in the acoustic wave filter may be coupled to a common node of the quadplexer through the series BAW resonator. All SAW resonators of each acoustic wave filter are coupled to a common node through the series BAW resonators of the respective acoustic wave filter. This can reduce the load on the common node relative to an acoustic wave filter including only surface acoustic wave resonators. At least 70% of the resonators of the multiplexer and acoustic wave filter may be SAW resonators, and the other resonators of the multiplexer and acoustic wave filter may be implemented by BAW technology. By implementing an acoustic wave filter using most SAW resonators, such an acoustic wave filter can be cheaper than an acoustic wave filter implemented mostly or entirely by BAW resonators.

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. An acoustic wave filter based on combined application of SAW-BAW technology, characterized in that: the system comprises a TX1 port, an RX1 port, a TX2 port and an RX2 port which are respectively connected with a COM port, wherein the TX1 port, the RX1 port, the TX2 port and the RX2 port are all connected with the COM port in parallel through different filter branches, and the filter branches of the TX1 port, the RX1 port, the TX2 port and the RX2 port all comprise a plurality of SAW resonators and a plurality of BAW resonators.

2. An acoustic wave filter based on the combined application of SAW-BAW technology according to claim 1, characterized in that: the filter branch circuit connected with the TX1 port and the COM port comprises a first SAW resonator (21), a second SAW resonator (23) and a first BAW resonator (25) which are sequentially connected in series, a third SAW resonator (22) is connected between the first SAW resonator (21) and the second SAW resonator (23) in parallel, a fourth SAW resonator (24) is connected between the second SAW resonator (23) and the first BAW resonator (25) in parallel, and one ends of the third SAW resonator (22) and the fourth SAW resonator (24) are grounded.

3. An acoustic wave filter based on the combined application of SAW-BAW technology according to claim 1, characterized in that: the filter branch circuit connected with the RX1 port and the COM port comprises a SAW resonator five (31), a SAW resonator six (33) and a BAW resonator two (36) which are sequentially connected in series, a SAW resonator seven (32) is connected between the SAW resonator five (31) and the SAW resonator six (33) in parallel, a SAW resonator eight (34) is connected between the SAW resonator six (33) and the BAW resonator two (36) in parallel, and one end of each of the SAW resonator seven (32) and the SAW resonator eight (34) is grounded.

4. An acoustic wave filter based on the combined application of SAW-BAW technology according to claim 1, characterized in that: the filter branch circuit connected with the TX2 port and the COM port comprises a SAW resonator nine (41), a SAW resonator ten (43) and a BAW resonator three (46) which are sequentially connected in series, a SAW resonator eleven (45) is connected in parallel between the TX2 port and the SAW resonator nine (41), a SAW resonator twelve (42) is connected in parallel between the SAW resonator nine (41) and the SAW resonator ten (43), a SAW resonator thirteen (44) is connected in parallel between the SAW resonator ten (43) and the BAW resonator three (46), a BAW resonator four (47) is connected in parallel between the BAW resonator three (46) and the COM port, and one end of each of the SAW resonator eleven (45), the SAW resonator twelve (42), the SAW resonator thirteen (44) and the BAW resonator four (47) is grounded.

5. An acoustic wave filter based on the combined application of SAW-BAW technology according to claim 1, characterized in that: the filter branch circuit connected with the RX2 port and the COM port comprises a SAW resonator fourteen (51), a SAW resonator fifteen (53) and a BAW resonator five (56) which are sequentially connected in series, the SAW resonator sixteen (55) is connected between the RX2 port and the SAW resonator fourteen (51) in parallel, the SAW resonator fourteen (51) and the SAW resonator fifteen (53) are connected in parallel with a SAW resonator seventeen (52), the SAW resonator fifteen (53) and the BAW resonator five (56) are connected in parallel with a SAW resonator eighteen (54), and one end of each of the SAW resonator sixteen (55), the SAW resonator seventeen (52) and the SAW resonator eighteen (54) is grounded.