CN111865350B

CN111865350B - Front end module

Info

Publication number: CN111865350B
Application number: CN202010009298.8A
Authority: CN
Inventors: 赵强大; 千成钟
Original assignee: Samsung Electro Mechanics Co Ltd
Current assignee: Samsung Electro Mechanics Co Ltd
Priority date: 2019-04-05
Filing date: 2020-01-06
Publication date: 2021-12-17
Anticipated expiration: 2040-01-06
Also published as: KR102260375B1; KR102428338B1; CN111865350A; KR20200127953A; KR20200117810A

Abstract

A front end module includes an antenna terminal and a duplexer including a first filter and a second filter, the first filter being connected to the antenna terminal and the first terminal and configured to perform cellular communication within a 3.3GHz to 4.2GHz band, the second filter being connected to the antenna terminal and the second terminal and configured to perform Wi-Fi communication within a 5.15GHz to 5.950GHz band, wherein each of the first filter and the second filter includes an LC filter, and a portion of an operating period of the first filter overlaps a portion of an operating period of the second filter.

Description

Front end module

This application claims the benefit of priority of korean patent application No. 10-2019-0039982 filed on korean intellectual property office at 5.4.2019 and korean patent application No. 10-2019-0073503 filed on 20.6.2019, which are incorporated herein by reference in their entireties for all purposes.

Technical Field

The following description relates to a front-end module.

Background

Compared to conventional Long Term Evolution (LTE) communications, fifth generation (5G) communications are expected to effectively connect more devices to each other with larger amounts of data and faster data transfer rates.

The 5G communication is progressing toward using a frequency band of 24250MHz to 52600MHz corresponding to a millimeter wave (mmWave) frequency band and a frequency band of 450MHz to 6000MHz corresponding to a sub-6GHz band or less.

Each of the n77 frequency band (3300MHz to 4200MHz), the n78 frequency band (3300MHz to 3800MHz), and the n79 frequency band (4400MHz to 5000MHz) is defined as one frequency band from the sub-6GHz operating frequency band, and the n77 frequency band, the n78 frequency band, and the n79 frequency band are expected to be used as the main frequency band due to the advantage of having a wide bandwidth for use as the main frequency band.

In the sub-6GHz band, a 4 × 4 multiple input/multiple output (MIMO) system is mainly used as a way to improve frequency efficiency. MIMO is a technology in which the bandwidth can be increased in proportion to the number of antennas. Thus, in the example using four antennas, four times the frequency efficiency of a single antenna may be obtained accordingly. However, due to slimness and miniaturization of mobile devices, there is a limit to a space in which an antenna can be mounted. There are additional physical limitations when four antennas are implemented in a terminal, given the existence of antennas for use in existing systems.

Disclosure of Invention

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In one general aspect, a front end module includes: an antenna terminal; and a duplexer including a first filter connected to the antenna terminal and the first terminal and configured to perform cellular communication within a 3.3GHz to 4.2GHz band, and a second filter connected to the antenna terminal and the second terminal and configured to perform Wi-Fi communication within a 5.15GHz to 5.950GHz band, wherein each of the first filter and the second filter includes an LC filter, and a portion of an operation period of the first filter overlaps a portion of an operation period of the second filter.

The front-end module may further include an impedance matching component configured to match an impedance of a pass band of the first filter to an impedance of a pass band of the second filter.

The impedance matching component may include a matching inductor disposed between the antenna terminal and ground.

The first filter may include a series-connected component connected in series between the antenna terminal and the first terminal and a shunt-connected component (shunt) respectively disposed between ground and different nodes between the antenna terminal and the first terminal.

One of the series-connected components from the series-connected components may include a capacitor and an inductor connected in parallel with each other and configured to form an attenuation pole at 5.90GHz to 6.0GHz, and another of the series-connected components may include a capacitor and an inductor connected in parallel with each other and configured to form an attenuation pole at 2.25GHz to 2.35 GHz.

The one of the series-connected components may be configured to form an attenuation pole at 5.95GHz and the other of the series-connected components may be configured to form an attenuation pole at 2.3 GHz.

A first of the shunt-connected components may include a capacitor and an inductor connected in series with each other and configured to form an attenuation pole at 1.95GHz to 2.05GHz, a second of the shunt-connected components may include a capacitor and an inductor connected in series with each other and configured to form an attenuation pole at 2.64GHz to 2.74GHz, and a third of the shunt-connected components may include a capacitor and an inductor connected in series with each other and configured to form an attenuation pole at 5.10GHz to 5.20 GHz.

The first shunt-connected component may be configured to form an attenuation pole at 2GHz, the second shunt-connected component may be configured to form an attenuation pole at 2.69GHz, and the third shunt-connected component may be configured to form an attenuation pole at 5.15 GHz.

The second filter may include a series-connected component connected in series between the antenna terminal and the second terminal and a shunt-connected component respectively disposed between ground and different nodes between the antenna terminal and the second terminal.

One of the shunt-connected components may include a capacitor and an inductor connected in series with each other and may be configured to form an attenuation pole at 4.15GHz to 4.25GHz, and another of the shunt-connected components may include a capacitor and an inductor connected in series with each other and may be configured to form an attenuation pole at 3.70GHz to 3.80 GHz.

The one shunt-connected component may be configured to form an attenuation pole at 4.20GHz and the other shunt-connected component may be configured to form an attenuation pole at 3.75 GHz.

The front end module may further include: a third filter having a pass band in a frequency band of 4.4GHz to 5.0 GHz; and a switch configured to selectively connect the duplexer and the third filter to the antenna terminal.

The front-end module may further include a fourth filter having a pass band of a 2.4GHz to 2.4835GHz band, wherein the fourth filter may be connected to an antenna terminal different from the antenna terminal connected to the duplexer.

In another general aspect, a front end module includes: an antenna terminal; and a duplexer including a first filter and a second filter, the first filter being connected to the antenna terminal, the second filter being configured to perform wireless communication of a standard different from a standard supported by the first filter in a frequency band different from a frequency band of the first filter, wherein each of the first filter and the second filter includes an LC filter, and a part of an operation period of the first filter overlaps with a part of an operation period of the second filter.

The first filter may be configured to support cellular communications in the 3.3GHz to 4.2GHz band, and the second filter may be configured to support Wi-Fi communications in the 5.15GHz to 5.950GHz band.

The first filter and the second filter may each have an attenuation characteristic of 35dB or greater.

In another general aspect, a front end module includes: an antenna terminal; and a duplexer including a first filter connected to the antenna terminal and the first terminal and configured to perform cellular communication and a second filter connected to the antenna terminal and the second terminal and configured to perform Wi-Fi communication, wherein each of the first filter and the second filter includes an LC filter, and a portion of an operation period of the first filter overlaps a portion of an operation period of the second filter.

The first filter may be configured to support cellular communications in a 3.3GHz to 4.2GHz frequency band and the second filter may be configured to support Wi-Fi communications in a 5.15GHz to 5.950GHz frequency band.

Other features and aspects will be apparent from the following detailed description, the accompanying drawings, and the claims.

Drawings

Fig. 1 is a block diagram illustrating a mobile device having a front end module according to an example installed thereon.

Fig. 2 is a block diagram of a front-end module according to an example.

Fig. 3 is a circuit diagram of a duplexer according to an example.

Fig. 4 shows a frequency response according to an example.

Fig. 5-7 are block diagrams of front end modules according to various examples.

Fig. 8 is a block diagram illustrating an example of an amplifying unit connected to a filter according to an example.

Like reference numerals refer to like elements throughout the drawings and detailed description. The figures may not be drawn to scale and the relative sizes, proportions and depictions of the elements in the figures may be exaggerated for clarity, illustration and convenience.

Detailed Description

The following detailed description of the present disclosure refers to the accompanying drawings that show, by way of illustration, specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure. It is to be understood that the various embodiments of the disclosure are different, but are not necessarily mutually exclusive. For example, the particular shapes, structures and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the present disclosure in combination with the embodiments. It is also to be understood that the location or arrangement of individual components within each embodiment disclosed may be modified without departing from the spirit and scope of the disclosure. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present disclosure is defined only by the appended claims, appropriately interpreted, along with the full range of equivalents to which such claims are entitled. In the drawings, like numerals refer to the same or similar functionality throughout the several views.

Hereinafter, examples will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily perform the present examples.

The following detailed description is provided to assist the reader in obtaining a thorough understanding of the methods, devices, and/or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and/or systems described herein will be apparent to those skilled in the art upon review of the disclosure of this application. For example, the order of operations described herein is merely an example and is not limited to the order set forth herein, but rather, variations may be made in addition to operations that must occur in a particular order, which will be apparent upon understanding the disclosure of the present application. Moreover, descriptions of features known in the art may be omitted for the sake of clarity and conciseness.

The features described herein may be embodied in different forms and should not be construed as limited to the examples described herein. Rather, the examples described herein have been provided merely to illustrate some of the many possible ways to implement the methods, devices, and/or systems described herein that will be apparent after understanding the disclosure of the present application.

Here, it is noted that the use of the term "may" with respect to an example or embodiment (e.g., with respect to what an example or embodiment may include or implement) means that there is at least one example or embodiment that includes or implements such a feature, and all examples and embodiments are not limited thereto.

Referring to the example of fig. 1, the mobile device 1 according to the example may include a plurality of antennas ANT 1 to ANT 6 and a plurality of front end modules FEM 1 to FEM 6 respectively connected to different antennas of the plurality of antennas ANT 1 to ANT 6.

The mobile device 1 may perform a variety of standard wireless communication tasks such as cellular (LTE/WCDMA/GSM) communication, 2.4GHz and 5GHz Wi-Fi communication, bluetooth communication, and other related wireless communication tasks. The plurality of antennas ANT 1 to ANT 6 and the plurality of front-end modules FEM 1 to FEM 6 included in the mobile device may be used to support various standard wireless communication tasks.

When a plurality of antennas are implemented in a limited space available in a mobile device, Radio Frequency (RF) signals input to or output from the plurality of antennas may interfere with each other, causing a problem of performance degradation.

Therefore, supporting multiple standard wireless communication tasks through a front-end module connected to a single antenna may be valuable for reducing or minimizing the number of antennas installed on the mobile device 1.

Fig. 2 is a block diagram of a front-end module according to an example.

The front end module according to an example may include a first antenna terminal T _ ant, a first terminal T1, a second terminal T2, and a duplexer DPX including both a first filter F1 and a second filter F2.

The first filter F1 may be disposed between the first antenna terminal T _ ant and the first terminal T1. In such an example, one end of the first filter F1 may be connected to the first antenna terminal T _ ANTa, and the other end of the first filter F1 may be connected to the first terminal T1.

Further, a second filter F2 may be disposed between the first antenna terminal T _ ant and the second terminal T2. One end of the second filter F2 may be connected to the first antenna terminal T _ ANTa, and the other end of the second filter F2 may be connected to the second terminal T2. In such an example, the second filter F2 may support wireless communication that uses a different standard than that supported by the first filter F1 and is also performed in a different frequency band than that of the first filter F1.

The first filter F1 may support cellular communication in a predetermined first frequency band selected from a group of sub-6GHz frequency bands. For example, the first filter F1 may support cellular communication in the 3.3GHz to 4.2GHz band (n77 band) corresponding to the first frequency band. According to another example, the first filter F1 may support cellular communication in the 3.3GHz to 3.8GHz band (n78 band).

The first filter F1 may operate as a band pass filter. For example, the first filter F1 may include a band pass filter having a pass band in the 3.3GHz to 4.2GHz band. Thus, such a band-pass filter may have a lower frequency of 3.3GHz and an upper frequency of 4.2 GHz. According to another example, the first filter F1 may include a band pass filter having a pass band in the 3.3GHz to 3.8GHz band. Thus, such a band-pass filter may have a lower frequency of 3.3GHz and an upper frequency of 3.8 GHz.

The second filter F2 may support Wi-Fi communications that occur in the 5GHz band. By way of example, the second filter F2 may support Wi-Fi communications in the 5.15GHz to 5.950GHz band.

The second filter F2 may operate as a band pass filter. For example, the second filter F2 may include a band pass filter having a pass band in the 5.15GHz to 5.950GHz band. Thus, the band pass filter has a lower limit frequency of 5.15GHz and an upper limit frequency of 5.950 GHz.

According to an example, a first filter F1 supporting cellular communications in the sub-6GHz band and a second filter F2 supporting Wi-Fi communications in the 5GHz band may be configured to form a single duplexer DPX. The first filter F1 and the second filter F2 may connect the duplexer DPX to one first antenna ant a, thereby enabling the number of antennas provided in the mobile device 1 to be greatly reduced. A part of the operation period of the first filter F1 provided in one duplexer DPX may overlap with a part of the operation period of the second filter F2. For example, the operation period of the first filter F1 may coincide with the operation period of the second filter F2, and due to such overlapping operation periods of the first filter F1 and the second filter F2, the first antenna ant may simultaneously perform cellular communication and Wi-Fi communication with the external device.

According to an example, the number of antennas provided in a mobile device may be reduced as compared to previous methods, and RF signals output from different antennas may be minimized or prevented from interfering with each other. Accordingly, the communication performance of the mobile device may be improved accordingly as compared to previous approaches. Furthermore, filters supporting different standards can be integrated into one front-end module, thereby reducing the overall area of the front-end module compared to previous approaches.

Referring to the example of fig. 2, since the first filter F1 for supporting cellular communication in the sub-6GHz band and the second filter F2 for supporting Wi-Fi communication in the 5GHz band share one antenna, a relatively high attenuation characteristic can be achieved in such an example, as compared to an example in which different filters are connected to different antennas.

For example, in an example, the first filter F1 and the second filter F2 may each have an attenuation characteristic of 25dB, and the first filter F1 supporting cellular communications in the sub-6GHz band and the second filter F2 supporting Wi-Fi communications in the 5GHz band are connected to separate antennas. In this example, when the first filter F1 and the second filter F2 are connected to one common antenna, each of the first filter F1 and the second filter F2 may have an overall attenuation characteristic of 35dB or more because an additional 10dB antenna isolation characteristic needs to be achieved.

Although Bulk Acoustic Wave (BAW) filters have excellent attenuation characteristics, BAW filters may not be readily applicable to fifth generation (5G) communications under study. The 5G communication requires a broadband frequency characteristic, and it may be difficult to form a relatively wide pass band using the BAW filter. Therefore, in order to satisfy the broadband frequency characteristics used in 5G communication, the filters may each be provided as an LC filter implemented as a combination of a capacitor and an inductor that function together as a filter.

Fig. 3 is a circuit diagram of a duplexer according to an example.

Referring to the example of fig. 3, the duplexer DPX may include a first filter F1, a second filter F2, and an impedance matching unit IMU. The impedance matching unit IMU may also be referred to as an impedance matching component.

Each of the first filter F1 and the second filter F2 may include an LC filter implemented as a combination of capacitors and inductors. For example, each of the first filter F1 and the second filter F2 may include an LC filter having an attenuation characteristic of 35dB or more. In general, each of the first filter F1 and the second filter F2 may include a number of series units and shunt units, which are also referred to as series-connected components and shunt-connected components, respectively. As discussed in further detail below, such series-connected components and shunt-connected components are formed using various arrangements of various passive elements such as inductors and capacitors.

The first filter F1 may include a plurality of series cells SE1, SE2, and SE3 arranged in series between the first antenna terminal T _ ANTa and the first terminal T1. The first filter F1 may further include a plurality of shunt units SH1, SH2, and SH3 arranged between ground and different nodes located between the first antenna terminal T _ ANTa and the first terminal T1.

For example, the plurality of series cells SE1, SE2, and SE3 may include a first series cell SE1, a second series cell SE2, and a third series cell SE3 sequentially arranged between the first antenna terminal T _ ANTa and the first terminal T1. The plurality of branching units SH1, SH2, and SH3 may include: a first shunt unit SH1 arranged between ground and a node between the first series unit SE1 and the second series unit SE 2; a second shunt unit SH2 arranged between ground and a node between the second series unit SE2 and the third series unit SE 3; and a third shunt unit SH3 provided between ground and a node between the third series unit SE3 and the first terminal T1.

The first series unit SE1 may include a capacitor C and an inductor L connected in parallel with each other and another capacitor C connected in series with the capacitor C and the inductor L connected in parallel with each other.

The second series unit SE2 may include a capacitor C, and the third series unit SE3 may include a capacitor C and an inductor L connected in parallel with each other and another inductor L connected in series with the capacitor C and the inductor L connected in parallel with each other.

Each of the first, second, and third shunt units SH1, SH2, and SH3 may include a capacitor C and an inductor L connected in series with each other.

The capacitor C and the inductor L connected in parallel to each other in the first series unit SE1 and the third series unit SE3 may form an attenuation pole by functioning to provide a parallel resonance. The first series unit SE1 may accordingly form an attenuation pole at 5.90GHz to 6.0GHz (e.g., specifically, at about 5.95 GHz). The third series unit SE3 may form an attenuation pole at 2.25GHz to 2.35GHz, respectively (e.g., specifically at about 2.3 GHz).

According to an example, the first filter F1 may improve attenuation characteristics with respect to a relatively high frequency band (high Wi-Fi 5GHz) from among Wi-Fi 5GHz bands according to an attenuation pole formed at about 5.95GHz by the first series cell SE1, and the first filter F1 may improve attenuation characteristics with respect to a relatively low frequency band (low LTE HB) from among LTE high frequency bands (HB) according to an attenuation pole formed at about 2.3GHz by the third series cell SE 3.

The capacitor C and the inductor L provided in the first, second, and third shunt units SH1, SH2, and SH3 may form an attenuation pole through series resonance. For example, the first branching unit SH1 may form an attenuation pole at 1.95GHz to 2.05GHz (e.g., about 2GHz), the second branching unit SH2 may form an attenuation pole at 2.64GHz to 2.74GHz (e.g., about 2.69GHz), and the third branching unit SH3 may form an attenuation pole at about 5.10GHz to about 5.20GHz (e.g., about 5.15 GHz).

According to an example, the first filter F1 may improve the attenuation characteristic with respect to the 1.7GHz to 2.0GHz band (LTE intermediate band (MB)) according to the attenuation pole formed at about 2GHz by the first shunt unit SH1, the first filter F1 may improve the attenuation characteristic with respect to the relatively high band (high LTE HB) in the 2.3GHz to 2.7GHz band (LTE HB) according to the attenuation pole formed at about 2.69GHz by the second shunt unit SH2, and the first filter F1 may improve the attenuation characteristic with respect to the relatively low band (low Wi-Fi 5GHz) from the Wi-Fi 5GHz band according to the attenuation pole formed at about 5.15GHz by the third shunt unit SH 3.

The second filter F2 may include: a plurality of series cells SE4, SE5, SE6, and SE7 arranged in series between the first antenna terminal T _ ANTa and the second terminal T2; and a plurality of shunt units SH4, SH5, and SH6 disposed between ground and different nodes between the first antenna terminal T _ ANTa and the second terminal T2.

For example, the plurality of series units SE4, SE5, SE6, and SE7 may include a fourth series unit SE4, a fifth series unit SE5, a sixth series unit SE6, and a seventh series unit SE 7. The plurality of series cells SE4, SE5, SE6, and SE7 may be sequentially arranged between the first antenna terminal T _ ANTa and the second terminal T2. The plurality of branching units SH4, SH5, and SH6 may include: a fourth shunt unit SH4 arranged between ground and a node between the fourth series unit SE4 and the fifth series unit SE 5; a fifth shunting unit SH5 arranged between ground and a node located between the fifth series unit SE5 and the sixth series unit SE 6; and a sixth shunting unit SH6 arranged between ground and a node located between the sixth series unit SE6 and the seventh series unit SE 7.

The fourth series unit SE4 may include a capacitor C and an inductor L connected in parallel to each other and another capacitor C connected in series to the capacitor C and the inductor L connected in parallel to each other. The fifth series unit SE5 may comprise an inductor L. Each of the sixth series unit SE6 and the seventh series unit SE7 may include a capacitor C.

The fourth shunt unit SH4 may include a capacitor C. Each of the fifth shunt unit SH5 and the sixth shunt unit SH6 may include a capacitor C and an inductor L connected in series with each other.

According to an example, the capacitor C and the inductor L connected in parallel to each other in the fourth series unit SE4 can realize the second high-frequency attenuation characteristic in the 11GHz band.

The capacitor C and the inductor L provided in each of the fifth shunt unit SH5 and the sixth shunt unit SH6 may form an attenuation pole through series resonance. The fifth shunting unit SH5 may form an attenuation pole at 4.15GHz to 4.25GHz (specifically, about 4.20 GHz). Sixth shunt unit SH6 may form an attenuation pole at 3.70GHz to 3.80GHz (specifically, about 3.75 GHz).

According to an example, the second filter F2 may improve the attenuation characteristics for a relatively high frequency band (high n77) of the n77 frequency band according to an attenuation pole formed at about 4.20GHz by the fifth shunt unit SH5, and the second filter F2 may improve the attenuation characteristics for a relatively middle frequency band (middle n77) of the n77 frequency band according to an attenuation pole formed at about 3.75GHz by the sixth shunt unit SH 6.

In order to realize one duplexer DPX by using the first filter F1 and the second filter F2, the impedance of the pass band of the first filter F1 may be matched with the impedance of the pass band of the second filter F2.

According to an example, the impedance matching unit IMU may be disposed between the first antenna terminal T _ ant and the first and second filters F1 and F2. Accordingly, the impedance of the pass band of each of the first filter F1 and the second filter F2 may be matched. The impedance matching unit IMU may be disposed between ground and a node connected to the first antenna terminal T _ ANTa, the first filter F1, and the second filter F2.

The impedance matching unit IMU may comprise a matching inductor Lmat arranged between the first antenna terminal T _ ANTa and ground. For example, the matching inductor Lmat may match the impedance of the pass band of each of the first filter F1 and the second filter F2 to 50 ohms.

In an example in which a phase shifter in which a plurality of elements are arranged in a pi shape or a T shape is used as an impedance matching unit, there is a disadvantage in that signal loss increases as the number of elements for matching impedance increases. In particular, in examples where components are placed in the signal path, signal loss tends to occur, even more.

According to an example, a matching inductor Lmat for matching impedance may be disposed between the first antenna terminal T _ ant and ground, instead of being directly disposed in the signal path, thereby being very advantageous in terms of signal loss.

Fig. 4 shows a frequency response according to an example.

In the example of fig. 4, a first curve (or curve 1) represents the frequency response of the first filter F1 and a second curve (or curve 2) represents the frequency response of the second filter F2.

Referring to the exemplary first curve (or curve 1) of fig. 4, the frequency response of the first filter F1 may have a pass characteristic of about-1.53 dB at about 3.3GHz and may have a pass characteristic of about-1.30 dB at about 4.20 GHz. Accordingly, the first filter F1 may have a relatively high attenuation characteristic for the 2.300GHz to 2.690GHz band allocated to the LTE communication band, and may also have a relatively high attenuation characteristic for the 5.15GHz to 5.950GHz band allocated to the Wi-Fi communication band.

Referring to the exemplary second curve (or curve 2) of fig. 4, the frequency response of the second filter F2 may have a pass characteristic of about-0.97 dB at about 5.15GHz, and may also have a pass characteristic of about-0.66 dB at about 5.95 GHz. Accordingly, the second filter F2 may have relatively high attenuation characteristics for the 3.3GHz to 4.2GHz band allocated to the sub-6GHz band.

According to an example, the first filter F1 may have an attenuation characteristic of about-39.05 dB at 5.15 GHz. The second filter F2 may have an attenuation characteristic of about-36.95 dB at 4.2 GHz. Therefore, due to these relatively high attenuation characteristics, even when the first filter F1 and the second filter F2 share a single antenna, it is possible to transmit and receive RF signals stably and without interference.

According to an example, since a filter having a relatively high attenuation characteristic can be realized by using a duplexer, such an example may be very advantageous in terms of signal loss, compared to a case where a separate duplexer is provided in addition to the filter. By using such an integrated duplexer, the area of the module can be reduced, and the manufacturing cost can also be reduced.

Fig. 5-7 are block diagrams of front end modules according to various examples.

The front end module according to the example of fig. 5 to 7 may be similar to the front end module according to the example of fig. 2, and therefore, for the sake of brevity, repeated descriptions are omitted and differences therebetween will be the focus of the description.

Referring to the example of fig. 5, the front end module according to the example of fig. 5 may further include a third filter F3 and a switch SW, as compared to the front end module according to the example of fig. 2. The third filter F3 may be disposed between the switch SW and the third terminal T3. In such an example, one end of the third filter F3 may be connected to the switch SW, and the other end of the third filter F3 may be connected to the third terminal T3.

The third filter F3 may support cellular communications in a predetermined second frequency band from the sub-6GHz frequency band. For example, the third filter F3 may support cellular communication in the 4.4GHz to 5.0GHz band (n79 band) corresponding to the second frequency band.

The third filter F3 may operate as a band pass filter. For example, the third filter F3 may include a band pass filter having a pass band in the 4.4GHz to 5.0GHz band. Such a filter may have a lower frequency of 4.4GHz and an upper frequency of 5.0 GHz.

For example, the switch SW may be implemented using a three-terminal switch in the form of a Single Pole Double Throw (SPDT). One end of the switch SW may be connected to the first antenna terminal T _ ANTa, and the other end of the switch SW may be selectively connected to the duplexer DPX and the third filter F3. In such an example, the switch SW may selectively connect the duplexer DPX and the third filter F3 to the first antenna terminal T _ ANTa.

Since band gaps between the 4.4GHz to 5.0GHz band corresponding to the pass band of the third filter F3, the 3.3GHz to 4.2GHz band corresponding to the pass band of the first filter F1, and the 5.15GHz to 5.950GHz band corresponding to the pass band of the second filter F2 are very narrow, it is possible to transmit and receive RF signals through the single first antenna ANTa in a time division manner by using the switch SW. Accordingly, the operation periods of the first and second filters F1 and F2 and the third filter F3 may be different from each other.

In addition to cellular communication in the n77 frequency band (3.3GHz to 4.2GHz) in the sub-6GHz band and Wi-Fi communication in the 5GHz band, the front-end module in accordance with this example may also perform cellular communication in the n79 frequency band (4.4GHz to 5.0GHz) in the sub-6GHz band.

Referring to the example of fig. 6, the front end module according to the example of fig. 6 may further include a fourth filter F4, as compared to the front end module according to the example of fig. 2.

The fourth filter F4 may be disposed between the second antenna terminal T _ ANTb and the fourth terminal T4. For example, one end of the fourth filter F4 may be connected to the second antenna terminal T _ ANTb, and the other end of the fourth filter F4 may be connected to the fourth terminal T4.

The fourth filter F4 may support Wi-Fi communication in the 2.4GHz band. For example, the fourth filter F4 may support Wi-Fi communications in the 2.4GHz to 2.4835GHz band.

The fourth filter F4 is operable as a band pass filter. For example, the fourth filter F4 may include a band pass filter having a pass band in the 2.4GHz to 2.4835GHz band. Such a band-pass filter may have a lower frequency of 2.4GHz and an upper frequency of 2.4835 GHz.

In addition to cellular communication in the n77 frequency band (3.3GHz to 4.2GHz) in the sub-6GHz band and Wi-Fi communication in the 5GHz band, the front-end module according to this example may also perform Wi-Fi communication in the 2.4GHz band.

Referring to the example of fig. 7, the front end module according to the example of fig. 7 may further include a third filter F3, a fourth filter F4, and a switch SW, as compared to the front end module according to the example of fig. 2. Since the third filter F3 and the switch SW and the fourth filter F4 in the example of fig. 7 are the same as the third filter F3 and the switch SW in fig. 5 and the fourth filter F4 in the example of fig. 6, respectively, a detailed description thereof is omitted for the sake of brevity.

In addition to cellular communication in the n77 frequency band (3.3GHz to 4.2GHz) in the sub-6GHz band and Wi-Fi communication in the 5GHz band, the front-end module in accordance with this example may also perform cellular communication in the n79 frequency band (4.4GHz to 5.0GHz) in the sub-6GHz band and Wi-Fi communication in the 2.4GHz band.

In the example of fig. 8, it is understood that the filter F may correspond to any one of the first, second, third, and fourth filters F1, F2, F3, and F4 according to the examples of fig. 2, 5, 6, and 7. It is also understood that the reception terminal Rx and the transmission terminal Tx may be included in any one of the first terminal T1, the second terminal T2, the third terminal T3, and the fourth terminal T4 according to the examples of fig. 2, 5, 6, and 7. For example, in the example of fig. 8, the first terminal T1 may include a reception terminal Rx and a transmission terminal Tx.

The amplification unit AU may comprise a switch SW, a low noise amplifier LNA and a power amplifier PA.

Referring to the example of fig. 8, the filter F may be selectively connected to one end of the low noise amplifier LNA and one end of the power amplifier PA through the switch SW. In such an example, the low noise amplifier LNA may be disposed in a reception path (Rx _ RF) of the RF signal, and the power amplifier PA may be disposed in a transmission path (Tx _ RF) of the RF signal. The other end of the low noise amplifier LNA may be connected to the reception terminal Rx, and the other end of the power amplifier PA may be connected to the transmission terminal Tx.

In the example of fig. 8, an example is shown in which the low noise amplifier LNA is disposed in the reception path Rx _ RF and the power amplifier PA is disposed in the transmission path Tx _ RF. In other examples, the low noise amplifier LNA may be removed from the receive path Rx _ RF or the power amplifier PA may be removed from the transmit path Tx _ RF, depending on the reasonable requirements for amplification in terms of design.

According to an example, the number of antennas employed in a mobile device may be reduced to improve isolation characteristics of the antennas.

While the present disclosure includes specific examples, it will be apparent upon an understanding of the present disclosure that various changes in form and detail can be made to these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered in a descriptive sense only and not for purposes of limitation. The description of features or aspects in each example will be considered applicable to similar features or aspects in other examples. Suitable results may be obtained if the described techniques were performed in a different order and/or if components in the described systems, architectures, devices, or circuits were combined in a different manner and/or replaced or added by other components or their equivalents. Therefore, the scope of the present disclosure is defined not by the detailed description but by the claims and their equivalents, and all modifications within the scope of the claims and their equivalents are to be construed as being included in the present disclosure.

Claims

1. A front-end module, comprising:

an antenna terminal; and

a duplexer including a first band pass filter connected to the antenna terminal and the first terminal and configured to perform cellular communication within a 3.3GHz to 4.2GHz band, and a second band pass filter connected to the antenna terminal and the second terminal and configured to perform Wi-Fi communication within a 5.15GHz to 5.950GHz band,

wherein each of the first and second band pass filters comprises an LC filter, and a portion of an operating period of the first band pass filter overlaps a portion of an operating period of the second band pass filter,

wherein the first band pass filter includes a series-connected component and a shunt-connected component, the series-connected component being connected in series between the antenna terminal and the first terminal, the shunt-connected component being respectively provided between ground and different nodes between the antenna terminal and the first terminal, and

wherein a first shunt-connected component from the shunt-connected components comprises a capacitor and an inductor connected in series with each other and configured to form an attenuation pole at 1.95GHz to 2.05GHz,

a second shunt-connected component from the shunt-connected components comprises a capacitor and an inductor connected in series with each other and configured to form an attenuation pole at 2.64GHz to 2.74GHz, and

a third shunt-connected component from the shunt-connected components includes a capacitor and an inductor connected in series with each other and is configured to form an attenuation pole at 5.10GHz to 5.20 GHz.

2. The front-end module of claim 1, further comprising an impedance matching component configured to match an impedance of a pass band of the first bandpass filter with an impedance of a pass band of the second bandpass filter.

3. The front-end module of claim 2, wherein the impedance matching component comprises a matching inductor disposed between the antenna terminal and ground.

4. The front-end module of claim 1, wherein the third shunt-connected component is configured to form an attenuation pole at 5.15 GHz.

5. The front-end module of claim 1, wherein a series-connected component from the series-connected components comprises a capacitor and an inductor connected in parallel with each other and configured to form an attenuation pole at 5.90GHz to 6.0GHz, and

another series-connected component from the series-connected components includes a capacitor and an inductor connected in parallel with each other and is configured to form an attenuation pole at 2.25GHz to 2.35 GHz.

6. The front-end module of claim 5, wherein the one of the series-connected components is configured to form an attenuation pole at 5.95GHz and the other of the series-connected components is configured to form an attenuation pole at 2.3 GHz.

7. The front-end module of claim 1, wherein the first and second band-pass filters each have an attenuation characteristic of 35dB or greater.

8. The front-end module of claim 7, wherein the first shunt-connected component is configured to form an attenuation pole at 2GHz,

the second shunt-connected component is configured to form an attenuation pole at 2.69GHz, and

the third shunt-connected component is configured to form an attenuation pole at 5.15 GHz.

9. The front-end module of claim 1, wherein the second bandpass filter includes a series-connected component and a shunt-connected component, the series-connected component connected in series between the antenna terminal and the second terminal, the shunt-connected component disposed between ground and different nodes between the antenna terminal and the second terminal, respectively.

10. The front-end module of claim 9, wherein the shunt-connected component from one of the shunt-connected components comprises a capacitor and an inductor connected in series with each other and configured to form an attenuation pole at 4.15GHz to 4.25GHz, and

another shunt-connected component from the shunt-connected components includes a capacitor and an inductor connected in series with each other and is configured to form an attenuation pole at 3.70GHz to 3.80 GHz.

11. The front-end module of claim 10, wherein the one shunt-connected component is configured to form an attenuation pole at 4.20GHz and the other shunt-connected component is configured to form an attenuation pole at 3.75 GHz.

12. The front-end module of claim 1, further comprising:

a third band pass filter having a pass band in a frequency band of 4.4GHz to 5.0 GHz; and

a switch configured to selectively connect the duplexer and the third band pass filter to the antenna terminal.

13. The front-end module of claim 1, further comprising a fourth bandpass filter having a passband in the 2.4GHz to 2.4835GHz band,

wherein the fourth band-pass filter is connected to an antenna terminal different from the antenna terminal connected by the duplexer.

14. A front-end module, comprising:

an antenna terminal; and

a duplexer including a first band pass filter and a second band pass filter, the first band pass filter being connected to the antenna terminal, the second band pass filter being configured to perform wireless communication of a standard different from a standard supported by the first band pass filter in a frequency band different from a frequency band of the first band pass filter,

wherein the first band pass filter includes a series-connected component and a shunt-connected component, the series-connected component being connected in series between the antenna terminal and the first terminal, the shunt-connected components being respectively provided between ground and different nodes located between the antenna terminal and the first terminal,

wherein a first of the shunt-connected components comprises a capacitor and an inductor connected in series with each other, and a second of the shunt-connected components comprises a capacitor and an inductor connected in series with each other.

15. The front-end module of claim 14, wherein the first band-pass filter is configured to support cellular communications within a 3.3GHz to 4.2GHz frequency band, and the second band-pass filter is configured to support Wi-Fi communications within a 5.15GHz to 5.950GHz frequency band.

16. The front-end module of claim 14, wherein the first and second band-pass filters each have an attenuation characteristic of 35dB or greater.

17. A front-end module, comprising:

an antenna terminal; and

a duplexer including a first band pass filter connected to the antenna terminal and the first terminal and configured to perform cellular communication and a second band pass filter connected to the antenna terminal and the second terminal and configured to perform Wi-Fi communication,

wherein each of the first and second band pass filters comprises an LC filter, and a portion of an operating period of the first band pass filter overlaps a portion of an operating period of the second band pass filter, and

18. The front-end module of claim 17, wherein the first band-pass filter is configured to support cellular communications within a 3.3GHz to 4.2GHz frequency band, and the second band-pass filter is configured to support Wi-Fi communications within a 5.15GHz to 5.950GHz frequency band.

19. The front-end module of claim 17, wherein the first and second band-pass filters each have an attenuation characteristic of 35dB or greater.

20. The front-end module of claim 17, further comprising an impedance matching component configured to match an impedance of a pass band of the first bandpass filter with an impedance of a pass band of the second bandpass filter.