WO2020093881A1

WO2020093881A1 - Internet of things duplexer

Info

Publication number: WO2020093881A1
Application number: PCT/CN2019/113272
Authority: WO
Inventors: 王震
Original assignee: 阿里巴巴集团控股有限公司
Priority date: 2018-11-07
Filing date: 2019-10-25
Publication date: 2020-05-14
Also published as: CN111162757A; TW202025628A

Abstract

An Internet of Things duplexer, comprising: a first port (10), a first bandpass filter circuit (11) connected to the first port (10), a second port (12), a second bandpass filter circuit (13) connected to the second port (12), a third port (14), and a third bandpass filter circuit (15), one end being connected to the third port (14), and the other end being connected to the first bandpass filter circuit (11) and the second bandpass filter circuit (13). The first bandpass filter circuit (11) and the third bandpass filter circuit (15) form a first channel between the first port (10) and the third port (14); the second bandpass filter circuit (13) and the third bandpass filter circuit (15) form a second channel between the second port (12) and the third port (14). The Internet of Things duplexer does not need to be made of a waveguide conductor material in the prior art, so that the size and weight of the Internet of Things duplexer can be reduced while an Internet of Things index is met.

Description

Internet of things duplexer

This application requires the priority of the Chinese patent application with the application number 201811320812.9 and the invention titled "An Internet of Things Duplexer" filed on November 07, 2018, the entire content of which is incorporated by reference in this application.

Technical field

This application relates to the field of communication technology, in particular to an Internet of Things duplexer.

Background technique

LoRa is an ultra-long-distance transmission scheme based on spread-spectrum technology in the Internet of Things. It has the characteristics of long transmission distance, low power consumption, multi-node and low cost. In the deployment of the Internet of Things, the LoRa gateway can use a duplexer for full Duplex communication.

At present, the duplexers used in the field of Internet of Things are all made of waveguide conductor materials. The isolation index of the duplexer is adjusted by adjusting the area of the wave-absorbing material on the surface of the waveguide, and the passband frequency and insertion loss of the duplexer are adjusted by PCB board impedance control. index.

This duplexer uses the cavity material to first make two high-band pass filters and low-pass filter devices, and then match them and then complete the production of the duplexer by adjusting the matching through the band-stop device. Due to the limitations of the manufacturing process, the device size is relatively large, the size is generally above 10cm, the weight is relatively heavy, and it is not easy to mass-produce. In addition, if the LoRa gateway installed with such a duplexer will also limit the volume of the LoRa gateway, the size of the LoRa gateway cannot be made small.

Summary of the invention

In view of the above problems, the embodiments of the present application are proposed in order to provide a duplexer that overcomes the above problems or at least partially solves the above problems.

In order to solve the above problems, an embodiment of the present application discloses an IoT duplexer, including:

The first port,

A first band-pass filter circuit connected to the first port,

Second port,

A second band-pass filter circuit connected to the second port,

Third port, and

A third bandpass filter circuit connected to the third port at one end and to the first bandpass filter circuit and the second bandpass filter circuit at the other end;

The first band-pass filter circuit and the third band-pass filter circuit constitute a first channel between the first port and the third port;

The second band-pass filter circuit and the third band-pass filter circuit constitute a second channel between the second port and the third port.

Preferably, the first band-pass filter circuit includes: a first band-pass filter connected to the first port, and a first matching circuit connected to the first band-pass filter;

The second bandpass filter circuit includes: a second bandpass filter connected to the second port, and a second matching circuit connected to the second bandpass filter;

The third band-pass filter circuit includes: a third band-pass filter connected to the third port, and a third matching circuit connected to the third band-pass filter;

The first matching circuit and the second matching circuit are connected to the same end of the third matching circuit.

Preferably, the first bandpass filter, the second bandpass filter, and the third bandpass filter are surface acoustic wave filters or thin film cavity acoustic resonance filters.

Preferably, the first matching circuit, the second matching circuit and the third matching circuit are π-type matching circuits.

Preferably, it further includes: a substrate;

The first port, the first bandpass filter, the first matching circuit, the second port, the second bandpass filter, the second matching circuit, the third port, The third band-pass filter and the third matching circuit are formed on the substrate.

Preferably, the isolation frequency band is greater than or equal to 10MHz.

Preferably, the in-band insertion loss of the first passband frequency band is 2.5dB-3.5dB, and the out-of-band suppression is less than -45dB;

The in-band insertion loss of the second passband frequency band is 2.5dB-3.5dB, and the out-of-band suppression is less than -45dB.

Preferably, the in-band insertion loss of the fourth pass-band frequency band of the first band-pass filter is less than or equal to 1 dB, the in-band width is 2 MHz, and the out-of-band suppression is less than -50 dB;

In-band insertion loss of the fifth passband frequency band of the second bandpass filter is less than or equal to 1dB, in-band width is 2MHz, and out-of-band rejection is less than -50dB;

The sixth band pass band of the third band pass filter has an in-band insertion loss less than or equal to 1 dB, an in-band width greater than or equal to 14 MHz, and an out-of-band rejection less than -50 dB.

An embodiment of the present application also discloses an IoT duplexer, including: a housing, a substrate housed in the housing, a first port, a first band-pass filter circuit connected to the first port, and a second A port, a second bandpass filter circuit connected to the second port, a third port, and one end connected to the third port, and the other end connected to the first bandpass filter circuit and the second bandpass filter The third band-pass filter circuit connected by the circuit;

The second band-pass filter circuit and the third band-pass filter circuit constitute a second channel between the second port and the third port;

The embodiments of the present application include the following advantages:

In the embodiment of the present application, the first channel between the first port and the third port can transmit the signal of the first passband frequency band; the second channel between the second port and the third port can transmit the second passband frequency band Signal; the first channel and the second channel are independent of each other. The signals of the two passband frequency bands can be simultaneously transmitted from the two channels without affecting each other, and duplex communication is realized. The IoT duplexer of the embodiment of the present application does not need to be made of the prior art waveguide conductor material, and can reduce the size and weight of the IoT duplexer if the IoT index is met.

BRIEF DESCRIPTION

FIG. 1 is a structural diagram of an embodiment of an Internet of Things duplexer of this application;

FIG. 2 is a structural diagram of an example of an Internet of Things duplexer according to an embodiment of the present application.

detailed description

In order to make the above objects, features and advantages of the present application more obvious and understandable, the present application will be described in further detail below with reference to the accompanying drawings and specific embodiments.

Referring to FIG. 1, it shows a structural diagram of an embodiment of an IoT duplexer of the present application, which may specifically include:

A first port 10, a first band-pass filter circuit 11 connected to the first port 10, a second port 12, a second band-pass filter circuit 13 connected to the second port 12, and a third port 14, and A third band-pass filter circuit 15 connected to the third port 14 at one end and to the first band-pass filter circuit 11 and the second band-pass filter circuit 13 at the other end;

The first band-pass filter circuit 11 and the third band-pass filter circuit 15 constitute a first channel between the first port 10 and the third port 14;

The second band-pass filter circuit 13 and the third band-pass filter circuit 15 constitute a second channel between the second port 12 and the third port 14.

In the embodiment of the present application, the first port 10 may be a receiving port or a transmitting port, the second port 12 may be a transmitting port or a receiving port, and the third port 14 may be a common antenna port. The first passband frequency band of the first port 10 is the passband frequency band of the first bandpass filter circuit 11, the second passband frequency band of the second port 12 is the passband frequency band of the second bandpass filter circuit 13, and the third port 14 The third passband frequency band is the passband frequency band of the third bandpass filter circuit 15.

The first channel between the first port 10 and the third port 14 can transmit signals in the first passband frequency band, and the second channel between the second port 12 and the third port 14 can transmit signals in the second passband frequency band, The first channel and the second channel are independent of each other. The signals of the two passband frequency bands can be simultaneously transmitted from the two channels without affecting each other, and duplex communication is realized. For example, the first port 10 may be a receiving port RX, the second port 12 may be a transmitting port TX, and the third port 14 may be an antenna port ANT. The signal of the first passband frequency band can be input from the first port 10 and output from the third port 14 through the first channel; meanwhile, the signal of the second passband frequency band can be input from the third port 14 and from the second channel through the second Port 12 output. The IoT duplexer of the embodiment of the present application does not need to be made of the prior art waveguide conductor material, and can reduce the size and weight of the IoT duplexer if the IoT index is met.

In the embodiment of the present application, there is an isolation frequency band between the first passband frequency band and the second passband frequency band; in order to meet the requirements in the field of the Internet of Things, in the embodiment of the present application, the first passband frequency band The isolation frequency band between the second passband frequency bands of the two ports may be 10MHz, and allows up and down movement. The width of the first passband frequency band and the width of the second passband frequency band may be 2 MHz, and are allowed to float up and down. The third passband frequency band includes the first passband frequency band, the second passband frequency band and the isolation frequency band, that is, the third passband frequency band may be 14 MHz, and it is allowed to float up and down.

2, a structural diagram of an example of an IoT duplexer according to an embodiment of the present application is shown, wherein the first band-pass filter circuit 11 may include: a first band connected to the first port 10 A pass filter 111, and a first matching circuit 112 connected to the first band pass filter 111;

The second band-pass filter circuit 13 may include: a second band-pass filter 131 connected to the second port 12 and a second matching circuit 132 connected to the second band-pass filter 131;

The third band-pass filter circuit 15 may include: a third band-pass filter 151 connected to the third port 14 and a third matching circuit 152 connected to the third band-pass filter 151;

The first matching circuit 112 and the second matching circuit 132 are connected to the same end of the third matching circuit 152.

In the embodiment of the present application, the first passband frequency band of the first port 10 is determined jointly by the fourth passband frequency band of the first bandpass filter 111 and the first matching circuit 112. The circuit index can be adjusted by adjusting the first matching circuit 112. Generally, the fourth passband frequency band of the first bandpass filter 111 is fixed, and the first passband frequency band can be adjusted by adjusting the first matching circuit 112.

The in-band width of the first band-pass filter 111 may be 2 MHz, so that the in-band width of the first pass-band frequency band may be 2 MHz. The in-band width of the second band-pass filter 131 may be 2 MHz, so that the in-band width of the second pass-band frequency band may be 2 MHz. There is an isolation frequency band of 10 MHz between the first band pass filter 111 and the second band pass filter 131, so that there is an isolation frequency band of 10 MHz between the first pass band frequency band and the second pass band frequency band. The in-band width of the third band-pass filter 151 may be greater than or equal to 14 MHz.

In order to meet the requirements of the Internet of Things, the first passband frequency band should meet the indicators of 3dB in-band insertion loss and -45dB out-of-band rejection, but in practice the first-band passband can have an insertion loss of 2.5dB-3.5dB , Out-of-band suppression can be less than -45dB.

Specifically, the in-band insertion loss of the first pass-band frequency band is composed of the in-band insertion loss of the first band-pass filter 111, the in-band insertion loss of the third band-pass filter 151, the first matching circuit 112, and the third matching Circuit 152 is determined. In order to make the first passband frequency band meet the index of 3dB, the band insertion loss of the first band pass filter 111 can be optimized, so that the first band pass filter 111 can have an insertion loss of less than or equal to 1dB ; The insertion loss of the third band-pass filter 151 can be optimized so that the insertion loss of the third band-pass filter 151 can be less than or equal to 1 dB; the first matching circuit 112 and / or the third matching circuit 152 can be adjusted To adjust the in-band insertion loss of the first passband frequency band.

However, optimizing the band-pass filter's in-band insertion loss will reduce the isolation, so it is necessary to improve the out-of-band rejection index of the first band-pass filter 111 and the third band-pass filter 151. The first band-pass filter 111 and The out-of-band rejection of the third band-pass filter 151 may be less than -50dB. Since the index of the out-of-band suppression of the first passband band is -45dB, the difference of 5dB can be provided by the first matching circuit 112 and the third matching circuit 152.

The second passband frequency band of the second port 12 is determined jointly by the fifth passband frequency band of the second bandpass filter 131 and the second matching circuit 132. The circuit index can be adjusted by adjusting the second matching circuit 132. Generally, the fifth passband frequency band of the second bandpass filter 131 is fixed, and the second passband frequency band can be adjusted by adjusting the second matching circuit 132.

In order to meet the requirements of the Internet of Things, the second passband frequency band should meet the indicators of 3dB in-band insertion loss and -45dB out-of-band rejection, but in practice the second-band passband can have an insertion loss of 2.5dB-3.5dB , Out-of-band suppression can be less than -45dB.

Specifically, the in-band insertion loss of the second passband frequency band is composed of the in-band insertion loss of the second bandpass filter 131, the in-band insertion loss of the third bandpass filter 151, the second matching circuit 132 and the third matching Circuit 152 is determined. In order to make the second passband frequency band meet the index of 3dB, the band insertion loss of the second bandpass filter 131 can be optimized so that the second bandpass filter 131 can have an insertion loss of less than or equal to 1dB ; The band insertion loss of the third band pass filter 151 can be optimized so that the band insertion loss of the third band pass filter 151 can be less than or equal to 1 dB; the second matching circuit 132 and / or the third matching circuit 152 can be adjusted To adjust the in-band insertion loss of the second passband frequency band.

However, optimizing the band-pass filter's in-band insertion loss will reduce the isolation, so it is necessary to increase the out-of-band rejection index of the second band-pass filter 131 and the third band-pass filter 151. The second band-pass filter 131 and The out-of-band rejection of the third band-pass filter 151 may be less than -50dB. Since the index of the out-of-band suppression of the second passband band is -45dB, the difference of 5dB can be provided by the second matching circuit 132 and the third matching circuit 152.

The third passband frequency band of the third port 14 is determined jointly by the sixth passband frequency band of the third bandpass filter 151 and the third matching circuit 152. The circuit index can be adjusted by adjusting the third matching circuit 152. Generally, the sixth passband frequency band of the third bandpass filter 151 is fixed, and the third passband frequency band can be adjusted by adjusting the third matching circuit 152.

In the embodiment of the present application, the first band pass filter 111, the second band pass filter 131, and the third band pass filter 151 may be surface acoustic wave (SAW) filters Or film cavity acoustic resonance (Film bulk acoustic resonance, FBAR) filter.

The size of the SAW filter or FBAR filter is very small, which can make the size of the duplexer very small, and can also meet the requirements of the Internet of Things field.

In the embodiment of the present application, the first matching circuit 112, the second matching circuit 132, and the third matching circuit 152 may be a π-type matching circuit, an L-type matching circuit, or even a double-L-type matching circuit. The specific matching circuit to be used depends on the difficulty of circuit debugging. Generally, the L-type circuit is the simplest. The π-type matching circuit has one more matching position than the L-type circuit. Therefore, a π-type matching circuit can be preferably used as the first matching circuit 112, the second matching circuit 132, and the third matching circuit 152.

In the embodiment of the present application, the IoT duplexer may further include: a substrate (not shown in the figure);

The first port 10, the first band pass filter 111, the first matching circuit 112, the second port 12, the second band pass filter 131, the second matching circuit 132, The third port 14, the third band-pass filter 151, and the third matching circuit 152 are formed on the substrate.

The substrate may be a ceramic substrate, when a SAW filter or FBAR filter is selected as the first band-pass filter 111, the second band-pass filter 131, and the third band-pass filter 151. The filter wafer is etched on the substrate, and then the filter is fabricated on the wafer; and other circuits are fabricated on the substrate.

An embodiment of the present application also discloses an Internet of Things duplexer, including: a housing, a substrate housed in the housing, a first port, a first band-pass filter circuit connected to the first port, and a second A port, a second bandpass filter circuit connected to the second port, a third port, and one end connected to the third port, and the other end connected to the first bandpass filter circuit and the second bandpass filter The third band-pass filter circuit connected by the circuit;

The specific structures of the first band-pass filter circuit, the second band-pass filter circuit, and the third band-pass filter circuit can refer to the foregoing embodiments, and details are not described herein.

Finally, it should also be noted that in this article, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply these entities Or there is any such actual relationship or order between operations. Moreover, the terms "include", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device that includes a series of elements includes not only those elements, but also those that are not explicitly listed The other elements listed may also include elements inherent to such processes, methods, articles or terminal equipment. Without more restrictions, the element defined by the sentence "include one ..." does not exclude that there are other identical elements in the process, method, article, or terminal device that includes the element.

The IoT duplexer provided in this application is described in detail above. Specific examples are used in this article to explain the principles and implementation of this application. The descriptions of the above embodiments are only used to help understand this application. Method and its core idea; meanwhile, for those of ordinary skill in the art, according to the ideas of this application, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be understood as a Application restrictions.

Claims

An Internet of Things duplexer, characterized in that it includes:

The first port,

A first band-pass filter circuit connected to the first port,

Second port,

A second band-pass filter circuit connected to the second port,

Third port, and

A third bandpass filter circuit connected to the third port at one end and to the first bandpass filter circuit and the second bandpass filter circuit at the other end;

The first band-pass filter circuit and the third band-pass filter circuit constitute a first channel between the first port and the third port;

The second band-pass filter circuit and the third band-pass filter circuit constitute a second channel between the second port and the third port.
The IoT duplexer according to claim 1, wherein:

The first band-pass filter circuit includes: a first band-pass filter connected to the first port, and a first matching circuit connected to the first band-pass filter;

The second bandpass filter circuit includes: a second bandpass filter connected to the second port, and a second matching circuit connected to the second bandpass filter;

The third band-pass filter circuit includes: a third band-pass filter connected to the third port, and a third matching circuit connected to the third band-pass filter;

The first matching circuit and the second matching circuit are connected to the same end of the third matching circuit.
The IoT duplexer according to claim 2, wherein the first bandpass filter, the second bandpass filter, and the third bandpass filter are surface acoustic wave filters or Thin film cavity acoustic resonance filter.
The IoT duplexer according to claim 2, wherein the first matching circuit, the second matching circuit, and the third matching circuit are π-type matching circuits.
The IoT duplexer according to claim 2, further comprising:

Substrate

The first port, the first bandpass filter, the first matching circuit, the second port, the second bandpass filter, the second matching circuit, the third port, The third band-pass filter and the third matching circuit are formed on the substrate.
The IoT duplexer according to claim 1, wherein there is an isolation frequency band between the first passband frequency band of the first port and the second passband frequency band of the second port, and the isolation frequency band Greater than or equal to 10MHz.
The Internet of Things duplexer according to claim 6, wherein:

The in-band insertion loss of the first passband frequency band is 2.5dB-3.5dB, and the out-of-band suppression is less than -45dB;

The in-band insertion loss of the second passband frequency band is 2.5dB-3.5dB, and the out-of-band suppression is less than -45dB.
The IoT duplexer according to claim 7, wherein:

In-band insertion loss of the fourth pass-band frequency band of the first band-pass filter is less than or equal to 1 dB, in-band width is 2 MHz, and out-of-band suppression is less than -50 dB;

In-band insertion loss of the fifth passband frequency band of the second bandpass filter is less than or equal to 1dB, in-band width is 2MHz, and out-of-band rejection is less than -50dB;

The sixth band pass band of the third band pass filter has an in-band insertion loss less than or equal to 1 dB, an in-band width greater than or equal to 14 MHz, and an out-of-band rejection less than -50 dB.
An Internet of Things duplexer, characterized by comprising: a housing, a substrate housed in the housing, a first port, a first band-pass filter circuit connected to the first port, and a second port, and A second bandpass filter circuit connected to the second port, a third port, and one end connected to the third port and the other end connected to the first bandpass filter circuit and the second bandpass filter circuit The third band-pass filter circuit;

The first band-pass filter circuit and the third band-pass filter circuit constitute a first channel between the first port and the third port;

The second band-pass filter circuit and the third band-pass filter circuit constitute a second channel between the second port and the third port;

The first port, the first band pass filter, the first matching circuit, the second port, the second band pass filter, the second matching circuit, the third port, the third A band-pass filter and a third matching circuit are formed on the substrate.