Power amplifier system

A power amplifier system includes: a drive stage configured to amplify an RF input signal and implemented in a substrate containing silicon; a power stage including a carrier amplifier configured to amplify a base signal from the RF input signal as amplified by the drive stage, and a peaking amplifier configured to amplify a peak signal from the RF input signal as amplified by the drive stage, the power stage being implemented in a substrate containing gallium arsenide; and a phase compensation circuit configured to change a phase of the RF input signal, wherein either the carrier amplifier or the peaking amplifier is connected to the phase compensation circuit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. § 119(a) of Korean Patent Application No. 10-2020-0117727 filed on Sep. 14, 2020 in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes.

BACKGROUND

The following description relates to a power amplifier system.

2. Description of Related Art

A wireless communication system adopts various digital modulation and demodulation methods depending on evolution of communication standards. An existing code division multiple access (CDMA) communication system employs a quadrature phase shift keying (QPSK) method, and a wireless LAN depending on an IEEE communication standard employs an orthogonal frequency division multiplexing (OFDM) method. In addition, recent 3GPP standard standards such as long term evolution (LTE), LTE-advanced, and 5G employ the QPSK method, a quadrature amplitude modulation (QAM) method, and the OFDM method. These wireless communication standards employ a linear modulation method requiring that a size or phase of a transmission signal be maintained during transmission.

Meanwhile, a transmission device used in a wireless communication system includes a power amplifier that amplifies a radio frequency (RF) signal in order to increase a transmission distance. This power amplifier, which is a circuit disposed at an end portion of a transmitting device, is an important circuit element that affects output power, linearity, and power efficiency of a wireless communication system.

3GPP newly defined the 5G NR (New Radio) standard developed from the existing LTE standard. It is required that the power amplifier have high linear power and high efficiency in order to meet the 5G NR specification, and it is also required that the power amplifier have high reliability. In addition, since an area and cost occupied by the power amplifier in the wireless communication system is large, it is desirable to reduce the area and cost of the power amplifier as the wireless communication system is miniaturized.

SUMMARY

In one general aspect, a power amplifier system includes: a drive stage configured to amplify an RF input signal and implemented in a substrate containing silicon; a power stage including a carrier amplifier configured to amplify a base signal from the RF input signal as amplified by the drive stage, and a peaking amplifier configured to amplify a peak signal from the RF input signal as amplified by the drive stage, the power stage being implemented in a substrate containing gallium arsenide; and a phase compensation circuit configured to change a phase of the RF input signal, wherein either the carrier amplifier or the peaking amplifier is connected to the phase compensation circuit.

The power amplifier system may further include: a first integrated circuit (IC) in which the drive stage is implemented; and a second IC in which the power stage is implemented independently of the first IC.

The power amplifier system may further include: a quarter wave circuit connected to an output stage of the carrier amplifier to change a phase of the amplified base signal.

The power amplifier system may further include: an inter-stage matcher including the phase compensation circuit, and configured to match impedance of a signal transfer path between the drive stage and the power stage.

The power amplifier system may further include: an input matcher including the phase compensation circuit, and configured to match impedance of a signal transfer path between a terminal for receiving the RF input signal and the power stage.

The drive stage may include: another carrier amplifier configured to amplify a base signal from the RF input signal; and another peaking amplifier configured to amplify a peak signal from the RF input signal.

The RF input signal may include an inverted RF input signal and a non-inverted RF input signal, and the drive stage may be further configured to amplify a difference between the inverted RF input signal and the non-inverted RF input signal.

The drive stage may include: a first drive amplifier configured to receive and amplify a non-inverted RF input signal of the RF input signal; and a second drive amplifier configured to receive and amplify an inverted RF input signal of the RF input signal.

The carrier amplifier may include: a first carrier amplifier configured to amplify a base signal from the non-inverted RF input signal as amplified by the first drive amplifier; and a second carrier amplifier configured to amplify a base signal from the inverted RF input signal as amplified by the second drive amplifier. The peaking amplifier may include: a first peaking amplifier configured to amplify a peak signal from the non-inverted RF input signal as amplified by the first drive amplifier; and a second peaking amplifier configured to amplify a peak signal from the inverted RF input signal as amplified by the second drive amplifier.

The drive stage may include: a first carrier amplifier configured to amplify a base signal from a non-inverted RF input signal of the RF input signal; a second carrier amplifier configured to amplify a base signal from an inverted RF input signal of the RF input signal; a first peaking amplifier configured to amplify a peak signal from the non-inverted RF input signal of the RF input signal; and a second peaking amplifier configured to amplify a peak signal from the inverted RF input signal of the RF input signal.

The carrier amplifier may further include: a third carrier amplifier configured to further amplify the amplified base signal from the non-inverted RF input signal; and a fourth carrier amplifier configured to further amplify the amplified base signal from the inverted RF input signal. The peaking amplifier may include: a third peaking amplifier configured to further amplify the amplified peak signal from the non-inverted RF input signal; and a fourth peaking amplifier configured to further amplify the amplified peak signal from the inverted RF input signal.

In another general aspect, a power amplifier system includes: a drive stage configured to amplify an RF input signal and implemented in a substrate containing silicon; a power stage including a carrier amplifier configured to amplify a base signal from the RF input signal as amplified by the drive stage, and a peaking amplifier configured to amplify a peak signal from the RF signal as amplified by the drive stage, the power stage being implemented in a substrate containing gallium arsenide; and an output matcher including a quarter wave circuit configured to match impedance of a signal transfer path between the power stage and a terminal for outputting an RF output signal, and change a phase of the amplified base signal.

The power amplifier system may further include: an inter-stage matcher including a phase compensation circuit configured to match impedance of a signal transfer path between the drive stage and the power stage, and change a phase of the RF input signal.

The power amplifier system may further include: an input matcher including a phase compensation circuit configured to match impedance of a signal transfer path between a terminal for receiving the RF input signal and the power stage, and change the phase of the RF signal.

The drive stage may include: another carrier amplifier configured to amplify a base signal from the RF input signal; and another peaking amplifier configured to amplify a peak signal from the RF input signal.

The RF input signal may include an inverted RF input signal and a non-inverted RF input signal, and the drive stage may be further configured to amplify a difference between the inverted RF input signal and the non-inverted RF input signal.

In another general aspect, a power amplifier system includes: a first integrated circuit (IC) formed on a first substrate made of a first material, the first IC including a drive stage configured to amplify an RF input signal; a second IC formed on a second substrate made of a second material different from the first material, the second IC including a power stage configured to amplify a base signal from the RF input signal as amplified by the drive stage, and a peaking amplifier configured to amplify a peak signal from the RF input signal as amplified by the drive stage; and a phase compensation circuit connected to the power stage, and configured to change a phase of the RF input signal.

The phase compensation circuit may be disposed in the first IC or the second IC.

The phase compensation circuit may be disposed in a base substrate on which the first IC and the second IC are mounted.

The phase compensation circuit may be disposed in either one of an inter-stage matcher configured to match impedance of a signal transfer path between the drive stage and the power stage, and an input matcher configured to match impedance of a signal transfer path between an input terminal for the RF input signal and the drive stage.

DETAILED DESCRIPTION

Herein, it is noted that use of the term “may” with respect to an embodiment or example, e.g., as to what an embodiment or example may include or implement, means that at least one embodiment or example exists in which such a feature is included or implemented while all examples and examples are not limited thereto.

Throughout the specification, a first portion being “mounted” in or on a second portion refers not only to a case in which the first portion is mounted outside of the second portion, but also to a case in which the first portion is mounted inside of or integrated in the second portion.

FIG.1illustrates a power amplifier system100, according to an embodiment.FIG.2illustrates example circuits for changing a phase of an input signal to +90 degrees or −90 degrees.

Referring toFIG.1, the power amplifier system100receives an RF input signal RFinand amplifies the received RF signal at a predetermined ratio to generate an RF output signal RFout. The power amplifier system100includes an input matching unit (or input matcher)10, a drive stage20, an inter-stage matching unit (or inter-stage matcher)30, a power stage40, and an output matching unit (or output matcher)50.

The input matching unit10may match impedance of a signal transfer path between the drive stage20and a terminal receiving the RF input signal RFin. The input matching unit10includes one or more input matching circuits11. For example, the input matching circuit11may be a circuit in which an inductor and a capacitor are connected. However, the input matching unit10may be omitted in the power amplifier system100.

The drive stage20receives power and amplifies the RF input signal. The drive stage20includes one or more drive amplifiers21. When the drive amplifier21amplifies the RF input signal based on a predetermined gain, a gain of the drive amplifier21may be determined based on a breakdown voltage of the drive amplifier21.

The drive stage20may be implemented as an integrated circuit (IC) by a semiconductor manufacturing process using a substrate containing silicon. The semiconductor manufacturing process using the substrate containing silicon has a relatively lower cost than a semiconductor manufacturing process using a substrate containing gallium arsenide. Accordingly, when the drive stage20is implemented in a silicon substrate, a cost of the power amplifier system100may be lowered. Furthermore, since the power amplifier system100occupies a largest proportion of a unit cost of a communication module, the unit cost of the communication module may be greatly reduced.

The input matching unit10and the drive stage20may be manufactured together as one IC by the semiconductor manufacturing process using the substrate containing silicon. In addition, in contrast to the drive stage20, the input matching unit10may not be implemented inside the IC, and may be directly mounted in the communication module independently of the IC. In this case, since the input matching unit10is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

The inter-stage matching unit30may match impedance of a signal transfer path between the drive terminal20and the power stage40. The inter-stage matching unit30may include a plurality of inter-stage matching circuits31and32. For example, each of the inter-stage matching circuits31and32may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. The inter-stage matching circuits31and32are respectively connected to a carrier amplifier41and a peaking amplifier42, which will be described later. In addition, the inter-stage matching circuits31and32may be integrated into one inter-stage matching circuit. However, the inter-stage matching unit30may be omitted in the power amplifier system100.

At least one of the inter-stage matching circuits31and32may include a phase compensation circuit for changing a phase of a signal that is input thereto. In addition, the phase compensation circuit may not be included in the inter-stage matching circuits31and32, and may be independently implemented. The phase compensation circuit may be connected to an input terminal of either the carrier amplifier41or the peaking amplifier42, and, accordingly, the phase of a signal that is input into either the carrier amplifier41or the peaking amplifier42may be changed. Such a phase compensation circuit, which is a circuit in which an inductor and a capacitor are connected, is included within the inter-stage matching unit30, and thus an area occupied by the phase compensation circuit in the power amplifier system is smaller than a case of using a quarter wave transmission line. Herein, the quarter wave transmission line is a circuit element that is independent of the inter-stage matching circuit31/32and has a large size. For example, the phase compensation circuit may be any one of the circuits illustrated inFIG.2. InFIG.2, circuits1001and1002may perform a phase change of +90 degrees, and circuits1003and1004may perform a phase change of −90 degrees.

The power stage40amplifies an RF signal from the drive stage20by receiving power. The power stage40includes one or more carrier amplifiers41and one or more peaking amplifiers42. When the carrier amplifier41and the peaking amplifier42are used, load impedance of each of the carrier amplifier41and the peaking amplifier42varies depending on an input power level. Due to such a change in the load impedance, amplification efficiency of the power stage40may be increased at both low input power and high input power. The carrier amplifier41is connected to a terminal of the RF output signal RFoutthrough an impedance inverter to amplify a base signal among RF signals amplified from the drive amplifier21. The peaking amplifier42is connected to the terminal of the RF output signal RFoutwithout using the impedance inverter to amplify a peak signal among the RF signals amplified from the drive amplifier21. Accordingly, the signals amplified by the carrier amplifier41and the peaking amplifier42are synthesized by the output matching unit50(to be described in more detail later) to output an RF signal, thereby generally increasing amplification efficiency of the power stage40. For example, when the carrier amplifier41has an operating point in a class B and the peaking amplifier42has an operating point in a class C, the peaking amplifier42starts an operation thereof when the carrier amplifier41is saturated.

The power stage40may be implemented as a single IC by a semiconductor manufacturing process using a substrate containing gallium arsenic. An IC formed on a substrate containing gallium arsenide can achieve higher power and higher linearity than an IC formed on the substrate containing silicon, and thus the RF signal amplified through the carrier amplifier41and the peaking amplifier42of the power stage40may have high power and linearity, and may have high reliability.

The output matching unit50may match impedance of a signal transfer path between the power stage40and a terminal through which the amplified RF output signal RFoutis outputted, and may change a phase of the signal output from the carrier amplifier41and synthesize the phase-changed signal output from the carrier amplifier41with the signal outputted from the peaking amplifier42to form a synthesized RF signal, and then output the synthesized RF signal to the terminal of the RF output signal RFout. The output matching unit50may include a plurality of output matching circuits51and52. For example, each of the output matching circuits51and52may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. However, the output matching unit50may be omitted in the power amplifier system100.

One of the output matching circuits51and52may include a quarter wave circuit for changing a phase of a signal that is input thereto. In addition, the quarter wave circuit may not be included in the output matching circuits51and52, and may be independently implemented. The quarter wave circuit may be one of the impedance inverters, and may be connected to an output terminal of the carrier amplifier41. Such a quarter wave circuit, which is a circuit in which an inductor and a capacitor are connected, is included within the output matching unit50, and thus an area occupied by the quarter wave circuit in the power amplifier system is smaller than a case in which a quarter wave transmission line is used. Herein, the quarter wave transmission line is a circuit element that is independent of the inter-stage matching circuit31/32and has a large size. For example, the quarter wave circuit may be any one of the circuits illustrated inFIG.2. InFIG.2, the circuits1001and1002may perform a phase change of +90 degrees, and the circuits1003and1004may perform a phase change of −90 degrees.

The output matching unit50and the power stage40may be manufactured together as one IC by the semiconductor manufacturing process using the substrate containing gallium arsenide. In addition, in contrast to the power stage40, the output matching unit50may not be implemented inside the IC, and may be directly mounted in the communication module independently of the IC. In this case, since the output matching unit50is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

The inter-stage matching unit30may be manufactured as a single IC by a semiconductor manufacturing process using a substrate containing gallium arsenide together with the power stage40. In addition, the inter-stage matching unit30may be manufactured as a single IC by a semiconductor manufacturing process using a substrate containing silicon together with the drive stage20, and, in this case, the manufacturing cost may be lower than a case in which the substrate containing gallium arsenic is used.

The inter-stage matching unit30may also not be included anywhere inside the IC in which the drive stage20is implemented or the IC in which the power stage40is implemented, and may be directly mounted in the communication module independently of these ICs. In this case, since the inter-stage matching unit30is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

Further, in the case where the inter-stage matching unit30includes a phase compensation circuit, when the inter-stage matching unit30is manufactured as a single IC together with the drive stage20and/or the power stage40, an IC manufacturing cost may increase compared with a case where the inter-stage matching unit30does not include the phase compensation circuit, due to an area occupied by the phase compensation circuit. Accordingly, in the case in which the inter-stage matching unit30includes the phase compensation circuit, when the inter-stage matching unit30is directly mounted in the communication module independently of the IC, a total manufacturing cost may be minimized. In addition, when the phase compensation circuit of the inter-stage matching unit30is directly mounted in the communication module independently of the IC, changes in load impedance of the carrier amplifier41and the peaking amplifier42may be optimized by optimizing inductance values or capacitance values of circuit elements constituting the phase compensation circuit.

FIG.3illustrates a power amplifier system100-1, according to an embodiment.

Referring toFIG.3, in the power amplifier system100-1, an input matching unit10-1includes a phase compensation circuit, but an inter-stage matching unit30-1does not include the phase compensation circuit, and a drive stage20-1includes a carrier amplifier22and a peaking amplifier23.

The phase compensation circuit may be connected to an input terminal of either the carrier amplifier22or the peaking amplifier23of the drive stage20-1, and accordingly, a phase of a signal that is input into either the carrier amplifier22and the peaking amplifier23may be changed. Such a phase compensation circuit, which is a circuit in which an inductor and a capacitor are connected, is included within the input matching unit10-1, and thus an area occupied by the phase compensation circuit in the power amplifier system100-1is smaller than a case in which a quarter wave transmission line is used. Herein, the quarter wave transmission line is a circuit element that is independent of the inter-stage matching circuit33/34and has a large size. For example, the phase compensation circuit may be any one of the circuits illustrated inFIG.2. InFIG.2, the circuits1001and1002may perform a phase change of +90 degrees, and the circuits1003and1004may perform a phase change of −90 degrees.

The input matching unit10-1may match impedance of a signal transfer path between the drive stage20-1and a terminal receiving the RF input signal RFin. The input matching unit10may include a plurality of input matching circuits12and13, and any one of the input matching circuits12and13may include a phase compensation circuit. In addition, the phase compensation circuit may not be included in the input matching circuits12and13, and may be independently implemented. For example, each of the input matching circuits12and13may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. The input matching circuits12and13are respectively connected to a carrier amplifier22and a peaking amplifier23. In addition, the input matching circuits12and13may be integrated into one inter-stage matching circuit. However, the input matching unit10may be omitted in the power amplifier system100-1.

The drive stage20-1receives power and amplifies the RF input signal. The drive stage20-1includes one or more carrier amplifiers22and one or more peaking amplifiers23. When the carrier amplifier22and the peaking amplifier23are used, load impedance of each of the carrier amplifier22and the peaking amplifier23varies depending on an input power level. Due to such a change in the load impedance, amplification efficiency of the drive stage20-1may be increased at both low input power and high input power. The carrier amplifier22is connected to a terminal of the RF output signal RFoutthrough an impedance inverter to amplify a base signal among RF input signals RFin. The peaking amplifier23is connected to a terminal of the RF output signal RFoutwithout using the impedance inverter to amplify a peak signal among RF input signals RFin. For example, when the carrier amplifier22has an operating point in a class B and the peaking amplifier23has an operating point in a class C, the peaking amplifier23starts an operation thereof when the carrier amplifier22is saturated.

The drive stage20-1may be implemented as a single IC by a semiconductor manufacturing process using a substrate containing silicon. The semiconductor manufacturing process using the substrate containing silicon has a relatively lower cost than a semiconductor manufacturing process using a substrate containing gallium arsenide. Accordingly, when the drive stage20-1is implemented in a silicon substrate, a cost of the power amplifier system100-1may be lowered. Furthermore, since the power amplifier system100-1occupies a largest proportion of a unit cost of a communication module, the unit cost of the communication module may be greatly reduced.

The input matching unit10-1and the drive stage20-1may be manufactured together as one IC by the semiconductor manufacturing process using the substrate containing silicon. In addition, in contrast to the drive stage20, the input matching unit10-1may not be implemented inside the IC, and may be directly mounted in the communication module independently of the IC. In this case, since the input matching unit10-1is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

Further, in the case in which the input matching unit10-1includes a phase compensation circuit, when the input matching unit10-1is manufactured as a single IC together with the drive stage20-1, an IC manufacturing cost may increase compared with a case in which the input matching unit10-1does not include the phase compensation circuit, due to an area occupied by the phase compensation circuit. Accordingly, in the case in which the input matching unit10-1includes the phase compensation circuit, when the input matching unit10-1is directly mounted in the communication module independently of the IC, a total manufacturing cost may be minimized. In addition, when the phase compensation circuit of the input matching unit10-1is directly mounted in the communication module independently of the IC, changes in load impedance of the carrier amplifier22and the peaking amplifier23may be optimized by optimizing inductance values or capacitance values of circuit elements constituting the phase compensation circuit.

The inter-stage matching unit30-1may match impedance of a signal transfer path between the drive terminal20-1and the power stage40, and does not include a phase compensation circuit. The inter-stage matching unit30-1may include a plurality of inter-stage matching circuits33and34. For example, each of the inter-stage matching circuits33and34may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. The inter-stage matching circuits33and34are respectively connected to a carrier amplifier43and a peaking amplifier44of the power stage40. In addition, the inter-stage matching circuits33and34may be integrated into one inter-stage matching circuit. However, the inter-stage matching unit30-1may be omitted in the power amplifier system100-1.

The power stage40amplifies an RF signal from the drive stage20-1by receiving power. The power stage40includes one or more carrier amplifiers43and one or more peaking amplifiers44. The carrier amplifier43of the power stage40is connected to a terminal of the RF output signal RFoutthrough an impedance inverter, and the peaking amplifier44of the power stage40is connected to the terminal of the RF output signal RFoutwithout using the impedance inverter. The base signal amplified through the carrier amplifier22of the drive stage20-1may be amplified through the carrier amplifier43of the power stage40, and the peak signal amplified through the peaking amplifier23of the drive stage20-1may be amplified through the peaking amplifier44of the power stage40. Accordingly, amplification efficiency of the power stage40may be increased as well as amplification efficiency of the drive stage20at both low input power and high input power, and thus amplification efficiency of the power amplifier system100-1may be maximized. For example, when the carrier amplifier43of the power stage40has an operating point in a class B and the peaking amplifier44of the power stage40has an operating point in a class C, the peaking amplifier44of the power stage40starts an operation thereof when the carrier amplifier43of the power stage40is saturated.

The power stage40may be implemented as a single IC by a semiconductor manufacturing process using a substrate containing gallium arsenic. An IC formed on a substrate containing gallium arsenide can achieve higher power and higher linearity than an IC formed on the substrate containing silicon, and, thus, the RF signal amplified through the carrier amplifier43and the peaking amplifier44of the power stage40may have high power and linearity, and may have high reliability.

The output matching unit50may match impedance of a signal transfer path between the power stage40and a terminal through which the amplified RF output signal RFoutis output, and may change a phase of the signal output from the carrier amplifier43of the power stage40and synthesize the phase-changed signal output from the carrier amplifier43with the signal output from the peaking amplifier44of the power stage40to form a synthesized RF signal, and then output the synthesized RF signal to the terminal of the RF output signal RFout. The output matching unit50may include a plurality of output matching circuits51and52. For example, each of the output matching circuits51and52may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. However, the output matching unit50may be omitted in the power amplifier system100.

One of the output matching circuits51and52may include a quarter wave circuit for changing a phase of a signal that is input thereto. In addition, the quarter wave circuit may not be included in the output matching circuits51and52, and may be independently implemented. The quarter wave circuit may be one of the impedance inverters, and may be connected to an output terminal of and carrier amplifier43of the power stage40. Such a quarter wave circuit, which is a circuit in which an inductor and a capacitor are connected, is included within the output matching unit50, and thus an area occupied by the quarter wave circuit in the power amplifier system is smaller than a case of using a quarter wave transmission line. Herein, the quarter wave transmission line is a circuit element that is independent of the inter-stage matching circuit33/34and has a large size. For example, the quarter wave circuit may be any one of the circuits illustrated inFIG.2. InFIG.2, the circuits1001and1002may perform a phase change of +90 degrees, and the circuits1003and1004may perform a phase change of −90 degrees.

The output matching unit50and the power stage40may be manufactured together as one IC by the semiconductor manufacturing process using the substrate containing gallium arsenide. In addition, in contrast to the power stage40, the output matching unit50is not implemented inside the IC, and may be directly mounted in the communication module independently of the IC. In this case, since the output matching unit50is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

The inter-stage matching unit30-1may be manufactured as a single IC by a semiconductor manufacturing process using a substrate containing gallium arsenide together with the power stage40. In addition, the inter-stage matching unit30-1may be manufactured as a single IC by a semiconductor manufacturing process using a substrate containing silicon together with the drive stage20-1, and, in this case, the manufacturing cost may be lower than a case in which the substrate containing gallium arsenic is used.

The inter-stage matching unit30-1may also not be included anywhere inside the IC in which the drive stage20-1is implemented or the IC in which the power stage40is implemented, and may be directly mounted in the communication module independently of these ICs. In this case, since the inter-stage matching unit30-1is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

FIG.4illustrates a power amplifier system100-2, according to an embodiment.

Referring toFIG.4, in the power amplifier system100-2, a drive stage20-2includes a pair of drive amplifiers211and212for performing differential amplification, and the drive amplifiers211and212receive power to amplify a difference between signals input thereto. The drive amplifiers211and212have a differential mode that greatly amplifies and outputs signals of opposite phases, and a common mode that cancels and outputs signals of a same phase. For example, the drive amplifiers211and212for performing differential amplification receive an inverted RF input signal RFinand a non-inverted RF input signal RFin, respectively, and thus a signal having an amplitude of approximately twice a sum of amplitudes of the inverted RF input signal RFinand the non-inverted RF input signal RFinmay be outputted in a differential mode. However, since voltages applied to the drive amplifiers211and212or currents flowing therein have a same phase, noise included in the voltages or currents may be canceled out of the output of the drive amplifiers211and212. Accordingly, the power amplifier system100-2for performing differential amplification may have high linear power and high efficiency.

The drive stage20-2may be implemented as a single IC by a semiconductor manufacturing process using a substrate containing silicon. The semiconductor manufacturing process using the substrate containing silicon has a relatively lower cost than a semiconductor manufacturing process using a substrate containing gallium arsenide. Accordingly, when the drive stage20-2is implemented in a silicon substrate, a cost of the power amplifier system100may be lowered. Furthermore, since the power amplifier system100-2occupies a largest proportion of a unit cost of a communication module, the unit cost of the communication module may be greatly reduced.

The input matching unit10-2may match impedance of a signal transfer path between the drive stage20-2and a terminal receiving the RF input signal RFin. The input matching unit10-2includes one or more input matching circuits14. For example, the input matching circuit14may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. The input matching circuit14receives the RF input signal RFinand then outputs the inverted RF input signal RFinand the non-inverted RF input signal RFin, and is connected to the drive amplifiers211and212. However, the input matching unit10-2may be omitted in the power amplifier system100.

The input matching unit10-2and the drive stage20-2may be manufactured together as one IC by the semiconductor manufacturing process using the substrate containing silicon. In addition, in contrast to the drive stage20, the input matching unit10-2may not be implemented inside the IC, and may be directly mounted in the communication module independently of the IC. In this case, since the input matching unit10-2is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

An inter-stage matching unit30-2may match impedance of a signal transfer path between the drive terminal20-2and a power stage40-1. The inter-stage matching unit30-2may include a plurality of inter-stage matching circuits35and36. For example, each of the inter-stage matching circuits35and36may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. The inter-stage matching circuits35and36are respectively connected to a pair of a carrier amplifier411and a peaking amplifier421, and another pair of a carrier amplifier412and a peaking amplifier422. In addition, each of the inter-stage matching circuits35and36may be divided into two parts, which are respectively connected to the carrier amplifiers411and412and the peaking amplifiers421and422one-by-one. However, the inter-stage matching unit30-2may be omitted in the power amplifier system100.

Each of the inter-stage matching circuits35and36may include a phase compensation circuit for changing a phase of a signal that is input thereto. In addition, the phase compensation circuit may not be included in the inter-stage matching circuits35and36, and may be independently implemented. The phase compensation circuit may be connected to an input terminal of either the carrier amplifier411or the peaking amplifier421, and accordingly, the phase of a signal that is input into either the carrier amplifier411or the peaking amplifier421may be changed. In addition, the phase compensation circuit may be connected to an input terminal of either the carrier amplifier412or the peaking amplifier422, and, accordingly, the phase of a signal that is input into either the carrier amplifier412or the peaking amplifier422may be changed. Such a phase compensation circuit, which is a circuit in which an inductor and a capacitor are connected, is included within the inter-stage matching unit30-2, and thus an area occupied by the phase compensation circuit in the power amplifier system is smaller than a case in which a quarter wave transmission line is used. Herein, the quarter wave transmission line is a circuit element that is independent of the inter-stage matching circuit30-2and has a large size. For example, the phase compensation circuit may be any one of the circuits illustrated inFIG.2. InFIG.2, the circuits1001and1002may perform a phase change of +90 degrees, and the circuits1003and1004may perform a phase change of −90 degrees.

The power stage40-1amplifies an RF signal from the drive stage20-2by receiving power. The power stage40-1includes the pair of the carrier amplifier411and a peaking amplifier421, and the other pair of the carrier amplifier412and the peaking amplifier422. When the carrier amplifiers411and412and the peaking amplifiers421and422are used, load impedance of each of the carrier amplifiers411and412and the peaking amplifiers421and422changes depending on an input power level. Due to such a change in the load impedance, amplification efficiency of the power stage40-1may be increased at both low input power and high input power. Each of the carrier amplifiers411and412is connected to a terminal of the RF output signal RFoutthrough an impedance inverter to amplify each base signal among RF signals amplified from the drive amplifiers211and212, respectively. Each of the peaking amplifiers421and422is connected to a terminal of the RF output signal RFoutwithout using the impedance inverter to amplify each peak signal among RF signals amplified from the drive amplifiers211and212, respectively. Accordingly, the signals amplified by the carrier amplifiers411and412and the peaking amplifiers421and422are synthesized by an output matching unit50-1to output an RF signal, thereby generally increasing amplification efficiency of the power stage40-1. For example, when each of the carrier amplifiers411and412has an operating point in a class B and each of the peaking amplifiers421and422has an operating point in a class C, the peaking amplifiers421and422start operations thereof when the carrier amplifiers421and422are saturated.

The power stage40-1may be implemented as a single IC by a semiconductor manufacturing process using a substrate containing gallium arsenic. An IC formed on a substrate containing gallium arsenide can achieve higher power and higher linearity than an IC formed on the substrate containing silicon, and thus the RF signal amplified through the carrier amplifiers411and412and the peaking amplifiers421and422of the power stage40-1may have high power and linearity, and may have high reliability.

The output matching unit50-1may match impedance of a signal transfer path between the power stage40-1and a terminal through which the amplified RF output signal RFoutis output, and may change phases of the signals output from the carrier amplifiers411and412and synthesize the phase-changed signals output from the carrier amplifiers411and412with the signals output from the peaking amplifiers421and422, respectively, to form respective synthesized RF signals, and then output the respective synthesized RF signals to the terminal of the RF output signal RFout. The output matching unit50-1may include a plurality of output matching circuits53,54, and55. For example, each of the output matching circuits53,54, and55may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. However, the output matching unit50may be omitted in the power amplifier system100.

One of the output matching circuits53,54, and55may include a quarter wave circuit for changing a phase of a signal that is input thereto. In addition, the quarter wave circuit may not be included in the output matching circuits53,54, and55, and may be independently implemented. The quarter wave circuit may be one of the impedance inverters, and may be connected to an output terminal of each of the carrier amplifiers411and412. Such a quarter wave circuit, which is a circuit in which an inductor and a capacitor are connected, is included within the output matching unit50-1, and thus an area occupied by the quarter wave circuit in the power amplifier system is smaller than a case in which a quarter wave transmission line is used. Herein, the quarter wave transmission line is a circuit element that is independent of the inter-stage matching circuit35/36and has a large size. For example, the quarter wave circuit may be any one of the circuits illustrated inFIG.2. InFIG.2, the circuits1001and1002may perform a phase change of +90 degrees, and the circuits1003and1004may perform a phase change of −90 degrees.

The output matching unit50-1together with the power stage40-2may be manufactured as one IC by the semiconductor manufacturing process using the substrate containing gallium arsenide. In addition, in contrast to the power stage40-2, the output matching unit50-1may not be implemented inside the IC, and may be directly mounted in the communication module independently of the IC. In this case, since the output matching unit50-1is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

The inter-stage matching unit30-2may be manufactured as a single IC by a semiconductor manufacturing process using a substrate containing gallium arsenide together with the power stage40-1. In addition, the inter-stage matching unit30-2may be manufactured as a single IC by a semiconductor manufacturing process using a substrate containing silicon together with the drive stage20-2, and, in this case, the manufacturing cost may be lower than a case of using the substrate containing gallium arsenic.

The inter-stage matching unit30-2may also not be included anywhere inside the IC in which the drive stage20-2is implemented or the IC in which the power stage40-1is implemented, and may be directly mounted in the communication module independently of these ICs. In this case, since the inter-stage matching unit30-2is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

Further, in the case in which the inter-stage matching unit30-2includes a phase compensation circuit, when the inter-stage matching unit30-2is manufactured as a single IC together with the drive stage20-2and/or the power stage40-1, an IC manufacturing cost may increase compared with a case where the inter-stage matching unit30-2does not include the phase compensation circuit, due to an area occupied by the phase compensation circuit. Accordingly, in the case in which the inter-stage matching unit30-2includes the phase compensation circuit, when the inter-stage matching unit30-2is directly mounted in the communication module independently of the IC, a total manufacturing cost may be minimized. In addition, when the phase compensation circuit of the inter-stage matching unit30-2is directly mounted in the communication module independently of the IC, changes in load impedance of the carrier amplifiers411and412and the peaking amplifiers421and422may be optimized by optimizing inductance values or capacitance values of circuit elements constituting the phase compensation circuit.

FIG.5illustrates a power amplifier system100-3, according to an embodiment.

Referring toFIG.5, in the power amplifier system100-3, an input matching unit10-3includes a phase compensation circuit, but an inter-stage matching unit30-3does not include the phase compensation circuit, and a drive stage20-3includes a pair of carrier amplifiers221and222respectively performing differential amplification and a pair of peaking amplifiers231and232.

The phase compensation circuit may be connected to an input terminal of any one of the pair of carrier amplifiers221and222of the drive stage20-3and the pair of peaking amplifiers231and232, and accordingly, a phase of a signal that is input into any one of the pair of carrier amplifiers221and222and the pair of peaking amplifiers231and232may be changed. Such a phase compensation circuit, which is a circuit in which an inductor and a capacitor are connected, is included within the input matching unit, and thus an area occupied by the phase compensation circuit in the power amplifier system100-3is smaller than a case in which a quarter wave transmission line is used. Herein, the quarter wave transmission line is a circuit element that is independent of the inter-stage matching circuit and has a large size. For example, the phase compensation circuit may be any one of the circuits illustrated inFIG.2. InFIG.2, the circuits1001and1002may perform a phase change of +90 degrees, and the circuits1003and1004may perform a phase change of −90 degrees.

An input matching unit10-3may match impedance of a signal transfer path between the drive stage20-3and a terminal receiving the RF input signal RFin. The input matching unit10-3may include a plurality of input matching circuits15and16, and any one of the input matching circuits15and16may include a phase compensation circuit. In addition, the phase compensation circuit may not be included in the input matching circuits15and16, and may be independently implemented. For example, each of the input matching circuits15and16may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. The input matching circuits15and16may be connected to the pair of carrier amplifiers221and222and the pair of peaking amplifiers231and232, respectively. In addition, each of the input matching circuits15and16may be divided into two parts, which are respectively connected to the carrier amplifiers221and222and the peaking amplifiers231and232one-by-one. However, the input matching unit10-3may be omitted in the power amplifier system100-3.

In the drive stage20-3, the carrier amplifiers221and222amplify a difference between signals input thereto, and the peaking amplifiers231and232also amplify a difference between signals input thereto. Each of the pair of carrier amplifiers221and222and the pair of peaking amplifiers231and232has a differential mode that greatly amplifies and outputs signals of opposite phases, and a common mode that cancels and outputs signals of a same phase. In addition, the carrier amplifiers221and222are connected to a terminal of the RF output signal RFoutthrough an impedance inverter to amplify a base signal in each of the RF input signals RFinhaving opposite phases, and a signal having an amplitude of approximately twice a sum of amplitudes of the base signals of the inverted RF input signal RFinand the non-inverted RF input signal RFinmay be output in a differential mode. The peaking amplifiers231and232are connected to a terminal of the RF output signal RFoutwithout using the impedance inverter to amplify a peak signal in each of the RF input signals RFinhaving opposite phases, and a signal having an amplitude of approximately twice a sum of amplitudes of the peak signals of the inverted RF input signal RFinand the non-inverted RF input signal RFinmay be output in a differential mode. However, since voltages applied to the carrier amplifiers221and222or currents flowing therein have a same phase, noise included in the voltages or currents may be canceled out of the output of the carrier amplifiers221and222. In addition, since voltages applied to the peaking amplifiers231and232or currents flowing therein have a same phase, noise included in the voltages or currents may be canceled out of the output of the peaking amplifiers231and232. Accordingly, the power amplifier system100-3for performing differential amplification may have high linear power and high efficiency. For example, when each of the carrier amplifiers221and222has an operating point in a class B and each of the peaking amplifiers231and232has an operating point in a class C, the peaking amplifiers231and232start operations thereof when the carrier amplifiers221and222are saturated.

The drive stage20-3may be implemented as a single IC by a semiconductor manufacturing process using a substrate containing silicon. The semiconductor manufacturing process using the substrate containing silicon has a relatively lower cost than a semiconductor manufacturing process using a substrate containing gallium arsenide. Accordingly, when the drive stage20-3is implemented in a silicon substrate, a cost of the power amplifier system100-3may be lowered. Furthermore, since the power amplifier system100-3occupies a largest proportion of a unit cost of a communication module, the unit cost of the communication module may be greatly reduced.

The input matching unit10-3and the drive stage20-3may be manufactured together as one IC by the semiconductor manufacturing process using the substrate containing silicon. In addition, in contrast the drive stage20, the input matching unit10-3may not be implemented inside the IC, and may be directly mounted in the communication module independently of the IC. In this case, since the input matching unit10-3is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

Further, in the case in which the input matching unit10-3includes a phase compensation circuit, when the inter-stage matching unit10-3is manufactured as a single IC together with the drive stage20-3, an IC manufacturing cost may increase compared with a case in which the input matching unit10-3does not include the phase compensation circuit, due to an area occupied by the phase compensation circuit. Accordingly, in the case in which the input matching unit10-3includes the phase compensation circuit, when the input matching unit10is directly mounted in the communication module independently of the IC, a total manufacturing cost may be minimized. In addition, when the phase compensation circuit of the input matching unit10-3is directly mounted in the communication module independently of the IC, changes in load impedance of the carrier amplifier221/222and the peaking amplifier231/232may be optimized by optimizing inductance values or capacitance values of circuit elements constituting the phase compensation circuit.

The inter-stage matching unit30-3may match impedance of a signal transfer path between the drive terminal20-3and a power stage40-2, and does not include a phase compensation circuit. The inter-stage matching unit30-3may include a plurality of inter-stage matching circuits37and38. For example, each of the inter-stage matching circuits37and38may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. The inter-stage matching circuits37and38are connected to a pair of carrier amplifiers431and432of the power stage40-2and a pair of peaking amplifiers441and442of the power stage40-2, respectively. In addition, each of the inter-stage matching circuits37and38may be divided into parts, which are respectively connected to the carrier amplifiers431and432and the peaking amplifiers441and442one-by-one. However, the inter-stage matching unit30-3may be omitted in the power amplifier system100.

The power stage40-2amplifies an RF signal from the drive stage20-3by receiving power. The power stage40-2includes the pair of carrier amplifiers431and432and the pair of peaking amplifiers441and442. The pair of the carrier amplifiers431and431of the power stage40-2are connected to a terminal of the RF output signal RFoutthrough an impedance inverter, and the pair of the carrier amplifiers441and431are connected to the terminal of the RF output signal RFoutusing the impedance inverter. The base signals amplified through the carrier amplifiers221and222of the drive stage20-3may be amplified through the carrier amplifiers431and432, and the peak signals amplified through the peaking amplifiers231and232of the drive stage20-3may be amplified through the carrier amplifiers441and442. Accordingly, amplification efficiency of the power stage40-2as well as amplification efficiency of the drive stage20-3may be increased at both low input power and high input power, and thus amplification efficiency of the power amplifier system100-3may be maximized. For example, when each of the carrier amplifiers431and432has an operating point in a class B and each of the peaking amplifiers441and442has an operating point in a class C, the peaking amplifiers441and442start operations thereof when the carrier amplifiers431and432are saturated.

The power stage40-2may be implemented as a single IC by a semiconductor manufacturing process using a substrate containing gallium arsenic. An IC formed on a substrate containing gallium arsenide can achieve higher power and higher linearity than an IC formed on the substrate containing silicon, and thus the RF signal amplified through the carrier amplifiers431and432and the peaking amplifiers441and442of the power stage40-2may have high power and linearity, and may have high reliability.

An output matching unit50-2may match impedance of a signal transfer path between the power stage40-2and a terminal through which the amplified RF output signal RFoutis output, and may change phases of the signals output from the carrier amplifiers431and431of the power stage40-2and synthesize the phase-changed signals output from the carrier amplifiers431and431with the signals output from the peaking amplifiers441and442of the power stage40-2to form synthesized RF signals, and then output the synthesized RF signals to the terminal of the RF output signal RFout. The output matching unit50-2may include a plurality of output matching circuits56,57, and58. For example, each of the output matching circuits56,57, and58may be a circuit in which an inductor and a capacitor are connected to each other, and may include a transformer. However, the output matching unit50-2may be omitted in the power amplifier system100.

One of the output matching circuits56,57, and58may include a quarter wave circuit for changing a phase of a signal that is input thereto. In addition, the quarter wave circuit may not be included in the output matching circuits56,57, and58, and may be independently implemented. The quarter wave circuit may be one of the impedance inverters, and may be connected to an output terminal of the carrier amplifiers431and432of the power stage40-2. Such a quarter wave circuit, which is a circuit in which an inductor and a capacitor are connected, is included within the output matching unit, and thus an area occupied by the quarter wave circuit in the power amplifier system100-3is smaller than a case in which a quarter wave transmission line is used. Herein, the quarter wave transmission line is a circuit element that is independent of the inter-stage matching circuit and has a large size. For example, the quarter wave circuit may be any one of the circuits illustrated inFIG.2. InFIG.2, the circuits1001and1002may perform a phase change of +90 degrees, and the circuits1003and1004may perform a phase change of −90 degrees.

The output matching unit50-2and the power stage40-2may be manufactured together as one IC by the semiconductor manufacturing process using the substrate containing gallium arsenide. In addition, in contrast to the power stage40-2, the output matching unit50-2may not be implemented inside the IC, and may be directly mounted in the communication module independently of the IC. In this case, since the output matching unit50-2is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

The inter-stage matching unit30-3may be manufactured as a single IC by a semiconductor manufacturing process using a substrate containing gallium arsenide, together with the power stage40-2. In addition, the inter-stage matching unit30-3may be manufactured as a single IC by a semiconductor manufacturing process using a substrate containing silicon, together with the drive stage20, and, in this case, the manufacturing cost may be lower than a case in which the substrate containing gallium arsenic is used.

The inter-stage matching unit30-3may also not be included anywhere inside the IC in which the drive stage20-3is implemented or the IC in which the power stage40-2is implemented, and may be directly mounted in the communication module independently of these ICs. In this case, since the inter-stage matching unit30-3is not implemented inside the IC, which is expensive, a total manufacturing cost may be reduced. In addition, in this case, since circuit elements having inductance values or capacitance values that are difficult to be used inside the IC may be directly mounted on the communication module, loss of an RF signal may be minimized and circuit optimization may be facilitated.

FIG.6illustrates a cross-section of a power amplifier system100-4, according to an exemplary embodiment.

Referring toFIG.6, the power amplifier system100-4includes the input matching unit10, the drive stage20, the inter-stage matching unit30, the power stage40, and the output matching unit50. The drive stage20and the power stage40are connected to each other through an electrical connection structure80on a base substrate90. For example, the electrical connection structure80may have a structure such as a solder ball, a pin, a land, or a pad. The drive stage20may be implemented as a single IC by a semiconductor manufacturing process using a substrate containing silicon, and the power stage40may be implemented as a single IC by a semiconductor manufacturing process using a substrate containing gallium arsenic.

Each of the input matching unit10, the inter-stage matching unit30, and the output matching unit50are integrated inside the base substrate90. In addition, at least one of the input matching unit10, the inter-stage matching unit30, and the output matching unit50may be installed outside the base substrate90independently of the drive stage20and the power stage40. At least one of the input matching unit10and the inter-stage matching unit30may be manufactured as a single IC together with the drive stage20to be connected to the base substrate90through the electrical connection structure80. At least one of the inter-stage matching unit30and the output matching unit50may be manufactured as a single IC together with the power stage40to be connected to the base substrate through the electrical connection structure80.

Referring toFIG.6, the power stage40., which requires relatively high linear power, may be implemented in a substrate containing gallium arsenide to implement the drive stage20, which requires relatively low power, on a substrate containing silicon having a low unit cost while efficiency of the power amplifier system100-4is increased, thereby reducing a cost of the power amplifier system100-4. At the same time, it is possible to facilitate power loss minimization and circuit optimization while reducing a manufacturing cost by directly mounting the inter-stage matching unit30in a communication module independently of the drive stage20and the power stage40.

FIG.7illustrates a top plan view of a communication system1, according to an embodiment.

Referring toFIG.7, the communication system1may include the power amplifier system100, a low noise amplifier200, a switch300, a coupler400, and a controller500.

Among the components constituting the communication system1, the power amplifier system100occupies a largest area in the communication system1. Accordingly, as described above, since the power amplifier system100has a small area, an entire size of the communication system1may be reduced.

The power amplifier system100may amplify an RF signal transmitted through an antenna. Accordingly, linear power and efficiency of the power amplifier system100may be increased, and reliability of the power amplifier system100may be increased, so that the communication system1may sufficiently satisfy the 5G NR standard.

The low noise amplifier200amplifies an RF signal received through an antenna. The low noise amplifier200may amplify a very small level of RF signal while distinguishing the RF signal from noise. That noise amplifier200may be disposed near the antenna. A band stop filter may be connected between the low noise amplifier200and the switch300. The band stop filter may allow only a signal of a specific frequency band to not pass therethrough.

The switch300may change a path for an RF signal passing through the power amplifier system100and the low noise amplifier200. For example, the switch300may be configured to allow either the power amplifier system100or the low noise amplifier200to receive the RF signal. In addition, the switch300may connect the power amplifier system100with the controller500of the communication system1, or may connect the power amplifier system100with a communication system having a different communication standard from that of the communication system1. The switch300may also connect the low noise amplifier200with the controller500of the communication system1, or may connect the low noise amplifier200with a communication system having a different communication standard from that of the communication system1.

The coupler400may perform power sampling or power dividing on an input RF signal. The coupler400is connected to the switch300. For example, the coupler400may detect power of the RF signal passing through the power amplifier system100and the low noise amplifier200, and the detected power may be used to control the power amplifier system100and the low noise amplifier200by using the controller500. In addition, the coupler400may divide and transmit an RF signal, and divided RF signals may be used in a plurality of communication systems, respectively. A band pass filter may be connected between the coupler400and the switch300. The band pass filter may transfer only a signal of a specific frequency band to a next stage, and may remove noise.

The controller500may be connected to the power amplifier system100, the low noise amplifier200, the switch300, and the coupler400to control the power amplifier system100, the low noise amplifier200, the switch300, and the coupler400. The controller500may include a memory, a processor, and the like to perform digital signal processing.

The communication system1may be implemented in electronic devices. For example, the electronic device may be a smart phone, a personal digital assistant, a digital video camera, a digital still camera, a network system, a computer, a monitor, a tablet, a laptop, a network, a television, a video game, a smart watch, an automotive device, or the like, but is not limited to such examples.