Doherty power amplifier in wireless communication system and electronic device including the same

Abstract

An electronic device may include a Doherty power amplifier. An electronic device may include a carrier amplifier, a first circuit coupled to an output terminal of the carrier amplifier, a peaking amplifier, a second circuit coupled to an output terminal of the peaking amplifier, and a network circuit.

Description

Technical Field

[0001] The present disclosure relates to a wireless communication system, and more particularly to a Doherty power amplifier in a wireless communication system and an electronic device including the same. Background Art

[0002] Products equipped with multiple antennas are being developed to improve communication performance, and it is expected that devices with an increasing number of antennas will be used by using massive multiple-input multiple-output (MIMO) technology. As the number of antenna elements in communication devices increases, the number of radio frequency (RF) components (e.g., power amplifiers (PAs)) inevitably increases accordingly.

[0003] The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above may be applicable as prior art with respect to the present disclosure. Summary of the invention

[0004] Technical issues

[0005] Aspects of the present disclosure address at least the above-mentioned problems and / or disadvantages and provide at least the advantages described below. Therefore, one aspect of the present disclosure is to provide an apparatus and method for extending a frequency band of a Doherty power amplifier in a wireless communication system.

[0006] Another aspect of the present disclosure is to provide a circuit of a Doherty power amplifier and a device including the same for improving the efficiency of a fifth generation (5G) transmitter in a wireless communication system.

[0007] Another aspect of the present disclosure is to provide a circuit of a Doherty power amplifier and an apparatus including the same for providing a high gain in a wide frequency band by dispersion of impedance in a frequency domain in a wireless communication system.

[0008] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments.

[0009] Solution

[0010] According to one aspect of the present disclosure, an electronic device including a Doherty power amplifier is provided. The electronic device includes a carrier amplifier, a first circuit coupled to an output terminal of the carrier amplifier, a peaking amplifier, a second circuit coupled to the output terminal of the peaking amplifier, and a network circuit. The network circuit may include a transmission line for impedance matching with a resonant circuit and a Doherty power amplifier. The resonant circuit may be arranged between a first region and a second region of the transmission line. In the electronic device, the Doherty power amplifier may provide an output impedance within a first range based on a frequency distribution within a bandwidth, and the network circuit may provide a load impedance. The network circuit may provide a load impedance within a second range based on a frequency distribution within a bandwidth. The first region of the transmission line may provide a first phase shift impedance to reduce the difference between the output impedance within the first range and the load impedance within the second range. The second region of the transmission line may provide a second phase shift impedance.

[0011] According to another aspect of the present disclosure, a radio frequency integrated circuit (RFIC) is provided. The RFIC includes a plurality of radio frequency (RF) processing chains. Each of the plurality of RF processing chains may include a phase shifter and a Doherty power amplifier. The Doherty power amplifier may include a carrier amplifier, a first circuit coupled to an output terminal of the carrier amplifier, a peak amplifier, a second circuit coupled to an output terminal of the peak amplifier, and a network circuit. The network circuit may include a transmission line for impedance matching with a resonant circuit and a Doherty power amplifier. In an electronic device, the resonant circuit may be arranged between a first region and a second region of the transmission line. The Doherty power amplifier may provide an output impedance within a first range based on a frequency distribution within a bandwidth, and the network circuit may provide a load impedance. The network circuit may provide a load impedance within a second range based on a frequency distribution within a bandwidth. The first region of the transmission line may provide a first phase shift impedance to reduce the difference between the output impedance within the first range and the load impedance within the second range. The second region of the transmission line may provide a second phase shift impedance.

[0012] Beneficial Effects

[0013] The Doherty power amplifier circuit and the electronic device including the same according to the embodiment of the present disclosure can provide a wide frequency band through a resonant circuit provided in a transmission line for impedance matching with an output terminal of the Doherty power amplifier.

[0014] Other aspects, advantages, and salient features of the present disclosure will become apparent to those skilled in the art from the following detailed description which, in conjunction with the accompanying drawings, discloses various embodiments of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent through the following description in conjunction with the accompanying drawings, in which:

[0016] Figure 1 A wireless communication system according to an embodiment of the present disclosure is shown;

[0017] Figure 2a An example of a Doherty power amplifier and network circuit arrangement according to an embodiment of the present disclosure is shown;

[0018] Figure 2b An example of a functional configuration of a Doherty power amplifier and a network circuit according to an embodiment of the present disclosure is shown;

[0019] Figure 3 shows an example of impedance rotation on a Smith chart according to an embodiment of the present disclosure;

[0020] Figure 4 shows examples of impedance rotation and dispersion according to embodiments of the present disclosure;

[0021] Figure 5a shows an example of the impedance of a network circuit according to an embodiment of the present disclosure;

[0022] Figure 5b shows an example of the impedance of a network circuit according to an embodiment of the present disclosure;

[0023] Figure 6 shows a functional configuration of a network circuit configured with a transmission line and a resonant circuit according to an embodiment of the present disclosure;

[0024] Figure 7 An example of a transmission line included in a network circuit according to an embodiment of the present disclosure is shown;

[0025] Figure 8a An example of a Doherty power amplifier circuit including a resonant circuit using a stub according to an embodiment of the present disclosure is shown;

[0026] Figure 8b An example of a Doherty power amplifier circuit including a resonant circuit using lumped elements according to an embodiment of the present disclosure is shown;

[0027] Fig. 9 An example of a resonant circuit included in a network circuit according to an embodiment of the present disclosure is shown;

[0028] Fig.10a An example of a network circuit including a transmission line and a resonant circuit according to an embodiment of the present disclosure is shown;

[0029] Fig.10b is an equivalent circuit diagram according to an embodiment of the present disclosure, in which some lumped elements in an equivalent circuit of a transmission line and some lumped elements in an equivalent circuit of a resonant circuit are combined in a network circuit;

[0030] Fig.11 An example of a Doherty power amplifier and network circuit according to an embodiment of the present disclosure is shown;

[0031] Fig.12a The effect of improving the power gain of the Doherty power amplifier through the network structure according to the embodiment of the present disclosure is shown;

[0032] Figure 12b The effect of improving the drain efficiency of the Doherty power amplifier through the network structure according to the embodiment of the present disclosure is shown;

[0033] Fig.13a An example of a power gain of a Doherty power amplifier in an average power region for each frequency based on whether a network circuit is added according to an embodiment of the present disclosure is shown;

[0034] Fig.13b The maximum output power of each frequency of the Doherty power amplifier based on whether a network circuit is added according to an embodiment of the present disclosure is shown;

[0035] Fig.13c shows the drain efficiency at the maximum output power of each frequency of the Doherty power amplifier based on whether a network circuit is added according to an embodiment of the present disclosure; and

[0036] Fig.13d The drain efficiency at the average output power at each frequency of the Doherty power amplifier according to an embodiment of the present disclosure based on whether a network circuit is added is shown.

[0037] Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures. DETAILED DESCRIPTION

[0038] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of the various embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details to assist in understanding, but these details should be considered as merely exemplary. Therefore, it will be appreciated by those of ordinary skill in the art that various changes and modifications may be made to the various embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and structures may be omitted for clarity and conciseness.

[0039] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present disclosure. Therefore, it will be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustrative purposes only and not for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents.

[0040] It should be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a component surface" includes reference to one or more of such surfaces.

[0041] In various embodiments of the present disclosure described below, a hardware method is described as an example. However, since various embodiments of the present disclosure include techniques using both hardware and software, various embodiments of the present disclosure do not exclude a software-based method.

[0042] For the convenience of description, the terms used in the following description referring to the amplifier of the electronic device and the related components connected to the amplifier (e.g., amplification circuit, amplifier circuit, matching circuit, impedance matching circuit, post-matching network, output matching circuit) are shown, the terms referring to the components (e.g., substrate, board, printed circuit board (PCB), flexible PCB (FPCB), module, antenna, antenna element, circuit, processor, chip, component, device), the terms referring to the shape of the component (e.g., structure, structure, support part, contact part, protruding part, opening part), the assembly referring to the connecting part between the structures (e.g., connecting part, contact part, contact structure, conductive part, assembly), the terms referring to the circuit (e.g., PCB, FPCB, signal line, feed line, data line, RF signal line, antenna line, RF path, RF module, RF circuit), etc. Therefore, the present disclosure is not limited to the terms described below, and another term with equivalent technical meaning can be used. In addition, the terms used below, such as "... module", "... unit", "... part", "... section", "... structure", "... body", etc., may mean at least one shape structure, and may also mean a unit of processing function.

[0043] In addition, in the present disclosure, in order to determine whether a specific condition is satisfied or satisfied, an expression of greater than or less than may be used, but this is only a description for expressing an example, and does not exclude a description of greater than or equal to or less than or equal to. A condition described as "greater than or equal to" may be replaced with "greater than", a condition described as "less than or equal to" may be replaced with "less than", and a condition described as "greater than or equal to and less than" may be replaced with "greater than and less than or equal to".

[0044] Hereinafter, the present disclosure relates to a power amplifier, a network circuit and an electronic device including the same in a wireless communication system. Specifically, the present disclosure proposes a circuit combining a Doherty power amplifier and a network circuit in a wireless communication system and an electronic device including the same. The network circuit may include a resonant circuit for band extension. In addition, by providing a capacitor and an inductor in the network circuit, miniaturization of a product including a Doherty power amplifier may be achieved.

[0045] Figure 1 A wireless communication system according to an embodiment of the present disclosure is shown.

[0046] refer to Figure 1 , FIG. 100 shows a base station 110, a terminal 120, and a terminal 130 as some of nodes using a radio channel in a wireless communication system. Figure 1 Only one base station is shown, but another base station that is the same as or similar to the base station 110 may also be included.

[0047] The base station 110 is a network infrastructure that provides radio access to the terminal 120. The base station 110 has a coverage range defined based on the distance at which a signal can be sent. The base station 110 may be referred to as a millimeter wave (mmWave) device, an access point (AP), an eNodeB (eNB), a fifth generation node (5G node), a 5G NodeB (NB), a wireless point, a transmission / reception point (TRP), an access unit, a distributed unit (DU), a radio unit (RU), a massive multiple input multiple output (MIMO) unit (MMU), a remote radio head (RRH), or another term having an equivalent technical meaning in addition to a base station. The base station 110 may send a downlink signal or may receive an uplink signal.

[0048] The terminal 120 is a device used by a user and communicates with the base station 110 through a radio channel. In some cases, the terminal 120 can be operated without user participation. In other words, the terminal 120 is a device that performs machine type communication (MTC) and may not be carried by the user. The terminal 120 may be referred to as a user equipment (UE), a mobile station, a subscriber station, a customer premises equipment (CPE), a remote terminal, a wireless terminal, an electronic device, a vehicle terminal, a user device, or another term having an equivalent technical meaning in addition to a terminal.

[0049] Figure 1The terminal 120 shown can support vehicle communication. In the case of vehicle communication, in the LTE system, the standardization work of vehicle-to-everything (V2X) technology based on device-to-device (D2D) communication structure is completed in the third generation partnership project (3GPP) version 14 and version 15, and efforts are currently being made to develop V2X technology based on 5G new radio (NR). In NR V2X, unicast communication, groupcast (or multicast) communication, and broadcast communication between terminals are supported.

[0050] The power amplifier described in the embodiments of the present disclosure is a component for power amplification of radio frequency (RF), and the operation and configuration of the present disclosure are described as an example of signal transmission in a base station, but the embodiments of the present disclosure are not limited thereto. The structure of the power amplifier proposed in the present disclosure and the device including the same can be implemented not only in a base station but also in a terminal. In other words, the embodiments of the present disclosure can be used not only for downlink transmission of a base station but also for uplink transmission of a terminal and sidelink communication of a terminal.

[0051] Figure 2a An example of a Doherty power amplifier and a network circuit arrangement according to an embodiment of the present disclosure is shown. The network circuit may not include a resonant circuit. The network circuit may include a transmission line for impedance matching.

[0052] refer to Figure 2a , the communication circuit 200 shows a Doherty power amplifier and a network circuit. The Doherty power amplifier may include a main amplifier terminal 202 and a carrier amplifier 201. The carrier amplifier 201 may include a first circuit 203 for output matching. The Doherty power amplifier may include a peak amplifier 204. The peak amplifier 204 may include an auxiliary amplifier terminal 205 and a second circuit 206 for output matching. The peak amplifier 204 may include an auxiliary amplifier terminal 205 and a second circuit 206 for output matching. The network circuit 207 may include a transmission line 208 having an electrical length of 90 degrees. The Doherty power amplifier may include a carrier amplifier 201 and a peak amplifier 204. The carrier amplifier 201 may be referred to as a main amplifier, and in addition to the peak amplifier 204, the peak amplifier 204 may also be referred to as an auxiliary amplifier. Typically, at low power, the carrier amplifier 201 operates to maintain high efficiency, and at high power, the two amplifiers (in other words, the carrier amplifier 201 and the peak amplifier 204) operate in parallel. Depending on the desired characteristics of the amplifier, the ratio of the two amplifiers may vary. In this case, impedance matching problems and power combining problems may occur. To solve this problem, the Doherty power amplifier may include a circuit for output matching.

[0053] The carrier amplifier 201 is typically a class AB (operating point moved to class A bias) or class B (operating point at the cutoff point of the transistor) amplifier, but the peak amplifier 204 is typically an amplifier of class C (operating point lower than the cutoff point of the transistor) amplifier and forms a lot of distortion. Linearity is maintained by adjusting the bias so that the distortion formed and the distortion of the carrier amplifier 201 are offset from each other. The Doherty power amplifier may include a structure for connecting the carrier amplifier 201 and the peak amplifier 204. In this case, the Doherty power amplifier may be coupled to a network circuit for impedance matching. The network circuit may include a transmission line 208 with an electrical length of a specified size (e.g., 90 degrees) for impedance matching.

[0054] The Doherty power amplifier may be connected to a transmission line 208. The transmission line 208 may be connected to the output of the carrier amplifier 201 of the Doherty power amplifier and the output of the peak amplifier 204 of the Doherty power amplifier. In other words, the Doherty power amplifier may have a structure for connecting the carrier amplifier 201 and the peak amplifier 204 in parallel based on a transmission line 208 having an electrical length of 90 degrees. As the power level increases, the amount of current provided to the load by the peak amplifier 204 increases. The efficiency of the amplifier may be increased by adjusting the load impedance and impedance matching of each of the carrier amplifier 201 and the peak amplifier 204. Specifically, the basic operating principle of the Doherty power amplifier may be interpreted as load modulation (or active load pull) by the output current of the peak amplifier 204. The operation of the Doherty power amplifier may be divided into three types: a low power level region, an intermediate power level region where load modulation occurs, and a maximum power level region. The peak amplifier 204 does not operate in the low power level region. The peak amplifier 204 may be regarded as an open circuit. In this case, the carrier amplifier 201 may operate at 2Ropt (Ropt: the optimal load impedance of the amplifier). The efficiency of the carrier amplifier 201 may increase simultaneously with the increase in output power, and may be saturated at a point 6 dB backed off from the maximum output level. In the intermediate power level region, the carrier amplifier 201 may be saturated and may operate at maximum efficiency. When the input power increases and reaches the 6 dB back-off point as the intermediate power level, the peak amplifier 204 may operate. The impedance conversion circuit may generate a load modulation from 2Ropt to Ropt. In the maximum power level region, the loads of the carrier amplifier 201 and the peak amplifier 204 operate as Ropt, and each amplifier may provide half the output power.

[0055] The communication circuit 200 represents a Doherty power amplifier, and the transmission line 208 used for impedance matching may have an electrical length of 90 degrees and a characteristic impedance Z0 When trying to convert Z L Convert to Z′ L When Z′ L is the appropriate impedance of the circuit for output matching of the carrier amplifier 201 and the peaking amplifier 204. 0 The characteristic impedance can be shown as Equation 1.

[0056] [Equation 1]

[0057]

[0058] Z 0 represents the characteristic impedance of the transmission line 208, Z L represents the load impedance, and Z′ L It can be the equivalent impedance required by the output matching circuit of the main amplifier and the output matching circuit of the auxiliary amplifier.

[0059] When the network circuit does not include a resonant circuit, the equivalent impedance Z′ of the first circuit 203 for matching and the second circuit 206 for matching L There is no dispersion according to frequency, so the frequency band may be limited compared to the case of impedance dispersion. On the Smith chart, the impedance of the Doherty circuit is plotted as an arc according to frequency, and the impedance Z′ L It can be in dotted form. Due to the impedance of the Doherty circuit and the impedance Z' L The difference between is small, so matching can be performed over a wider frequency band. In the case where only a resonant circuit is added to the network circuit, the dispersed impedance is not rotated. Therefore, by adding a resonant circuit to the transmission line of the rotating impedance, the impedance of the Doherty power amplifier and the impedance Z′ can be reduced. L The difference between. On the Smith chart, the impedance of the Doherty circuit plots an arc according to the frequency, and the impedance B also plots an arc according to the frequency. Therefore, the impedance of the Doherty circuit and the impedance Z' L In other words, by adding a resonant circuit to the transmission line, the Doherty power amplifier can be matched over a wider area.

[0060] Figure 2b An example of a functional configuration of a Doherty power amplifier and a network circuit according to an embodiment of the present disclosure is shown. The network circuit may include a transmission line and a resonant circuit for impedance matching. The transmission line may include a first region adjacent to the output of the Doherty power amplifier and a second region adjacent to the load impedance. Figure 2a The description of the Doherty power amplifier described in the above may be applied in the same or similar manner to Figure 2b Doherty power amplifier.

[0061] refer to Figure 2b , the communication circuit 250 may include a Doherty power amplifier and a network circuit 257. The Doherty power amplifier may include a carrier amplifier 251. The carrier amplifier 251 may include a main amplifier terminal 252 and a first circuit 253 for output matching. The Doherty power amplifier may include a peak amplifier 254. The peak amplifier 254 may include an auxiliary amplifier terminal 255 and a second circuit 256 for output matching.

[0062] The network circuit 257 may include a resonant circuit and a transmission line. The transmission line may provide a phase shift of a specified size (e.g., 90 degrees) for impedance matching. The transmission line may increase an electrical length corresponding to a quarter of the wavelength. The resonant circuit may be provided in the transmission line. Thus, the transmission line may be divided into two regions. The network circuit 257 may include a resonant circuit having a phase shift of θ 2 The first region of the transmission line having an electrical length of 2 A second region of a transmission line (hereinafter, second transmission line 260) having an electrical length of

[0063] The communication circuit 250 may include a Doherty power amplifier and a network circuit 257 for impedance dispersion coupled to the Doherty power amplifier. When the resonance circuit 259 is inserted between the first transmission line 258 and the second transmission line 260, the dispersion and rotation of impedance may be controlled.

[0064] The resonant circuit 259 can be implemented in various configurations. According to an embodiment, the resonant circuit 259 can be configured with an open circuit stub and a short circuit stub. According to an embodiment, the resonant circuit 259 can be configured with a series inductor and a series capacitor. According to an embodiment, the resonant circuit 259 may include a parallel inductor and a parallel capacitor. According to an embodiment, the resonant circuit 259 may include an open circuit stub and a parallel inductor. According to an embodiment, the resonant circuit 259 may include a short circuit stub and a parallel capacitor. However, it is not limited to such an embodiment.

[0065] The resonant circuit 259 of the network circuit 257 disperses the impedance. Here, the impedance refers to the impedance ZL' of the network circuit 257 observed from the output terminal of the Doherty power amplifier (for example, the output terminal of the first circuit 253 and the second circuit 256) toward the load. Although the resonant circuit 259 does not affect the impedance of the network circuit at the resonant frequency of the resonant circuit 259, the resonant circuit 259 disperses the impedance of the network circuit 257 in the frequency range near the resonant frequency. When the impedance is dispersed, an imaginary value is included in the impedance.

[0066] The first transmission line 258 and the second transmission line 260 rotate the dispersed impedance. The characteristic impedance of the first transmission line 258 is Z 0 , the electrical length is θ 2 The characteristic impedance of the second transmission line 260 is Z 0 , the electrical length is 90-θ 2 The network circuit 257 including the first transmission line 258 and the second transmission line 260 can provide a 90 degree phase shift as a whole.

[0067] The impedance of the network circuit is dispersed by the resonant circuit 259 and rotated by the first transmission line 258 and the second transmission line 260. Therefore, by changing the impedance of the resonant circuit 259 according to the frequency adjustment and the phase adjustment between the first transmission line 258 and the second transmission line 260, the difference between the impedance of the Doherty power amplifier (e.g., the impedance facing the Doherty power amplifier) ​​and the impedance of the network circuit 257 can be reduced.

[0068] Figure 3 An example of impedance rotation on a Smith chart is shown according to an embodiment of the present disclosure.

[0069] refer to Figure 3 , the communication circuit 300 may include a transmission line and an impedance. Input impedance 301 Z in = represents the impedance in the direction in which the transmission line 303 and the load are viewed from the input terminal of the transmission line. In other words, the input impedance 301 Z in It can be the impedance value before passing through the transmission line 303. Load impedance 305 Z L = represents the impedance in the direction in which the load is viewed from the output terminal of the transmission line. In other words, the load impedance 305 Z L It can be the impedance value after passing through the transmission line 303. The transmission line 303 can have Z 0 The characteristic impedance of θ and the electrical length of θ. The Smith chart 310 represents the impedance rotation performed by the transmission line of the communication circuit 300. Input impedance 301 Z in It can represent the impedance value before passing through the transmission line, the load impedance is 305 Z L It can represent the impedance value after passing through the transmission line. Input impedance 301 Z on Smith chart 310 in and load impedance 305 Z L The input impedance 301 Z of the communication circuit 300 is shown on the Smith chart 310. in and load impedance 305 Z L .

[0070] Smith Chart 310 Input Impedance 301 Z in It can rotate on a circle with a Z0 The reflection coefficient on the circle centered is the radius of |Γ|. Input impedance 301 Z in can be connected to Z through transmission line 303 0 In other words, the impedance of the load side can be changed from the input impedance 301 Z to the impedance θ based on the transmission line 303. in Rotate to load impedance 305 Z L .

[0071] Figure 4 Examples of impedance rotation and dispersion according to embodiments of the present disclosure are shown.

[0072] refer to Figure 4 , the communication circuit 400 shows an impedance matching network circuit for a Doherty power amplifier. The network circuit can be coupled to the output of the Doherty power amplifier. The communication circuit 400 can include a first transmission line 403, a resonant circuit 407, and a second transmission line 409. The transmission line input impedance 401 Z Tlin = represents the impedance in the direction from the input terminal of the first transmission line 403 to the first transmission line 403, the resonance circuit 407, the second transmission line 409 and the load impedance. The first transmission line 403 may have a characteristic impedance Z 0 and electrical length θ 2 The transmission line of the resonant circuit has an impedance of 405 Z res = represents the impedance in the direction from the input terminal of the resonant circuit 407 to the resonant circuit 407, the second transmission line 409, and the load impedance. The resonant circuit 407 may have a dispersion impedance in a range other than the resonant frequency. The second transmission line 409 may have a characteristic impedance Z 0 and electrical length 90-θ 2 transmission line.

[0073] The impedance rotation according to the arrangement of the resonant circuit 407 is shown on the Smith chart 410. Based on the signal transmission direction, the resonant circuit 407 may include a parallel arrangement of elements or a series arrangement of elements. res According to an embodiment, in the case where the resonant circuit 407 includes one or more lumped elements connected in parallel, the resonant circuit impedance 405 Z res It can be shown on the Smith chart as the parallel resonant circuit impedance 411 Z res-shunt According to an embodiment, in the case where the resonant circuit 407 includes one or more lumped elements connected in series, the resonant circuit impedance 405 Z res It can be shown on the Smith chart 410 as the series resonant circuit impedance 413 Z res-series .

[0074] According to an embodiment of the present disclosure, the first transmission line may rotate the dispersed impedance on the Smith chart 410. Here, the dispersed impedance means the parallel resonant circuit impedance 411 Z that is dispersed based on the change in frequency. res-shunt , or the series resonant circuit impedance 413 Z res-series For example, the transmission line input impedance is 401 Z Tlin It can be expressed as Equation 2.

[0075] [Equation 2]

[0076]

[0077] [Equation 3]

[0078] θ 2 (f) = k 2 (ff 20 )+θ 20

[0079] θ 2 k may represent the electrical length of the first transmission line 403 at frequency f. 2 It can represent the phase change degree according to the frequency of the first transmission line 403. 20 Can mean a center frequency. 20 Can mean the electrical length at the center frequency.

[0080] The resonant circuit may be configured based on various methods. According to an embodiment of the present disclosure, the resonant circuit may be configured by at least one of an open-circuited stub and a short-circuited stub. According to another embodiment, the resonant circuit may be configured by a parallel connection or a series connection of lumped elements (e.g., an inductor and a capacitor). According to yet another embodiment, the resonant circuit may be configured by a combination of lumped elements and stubs.

[0081] According to an embodiment of the present disclosure, the impedance of a resonant circuit configured with an open-circuited stub and a short-circuited stub may be as shown in Equation 4.

[0082] [Equation 4]

[0083]

[0084] Z 1 It can represent the characteristic impedance of the short stub. When the electrical length of the open short stub is θ 1 When the electrical length of the short-circuit stub can be 90-θ 1 The impedance can be dispersed counterclockwise according to the frequency on the Smith chart 410. 1 The degree of dispersion can be controlled by adjusting

[0085] According to an embodiment of the present disclosure, the impedance value of a resonant circuit configured with a parallel inductor and a parallel capacitor may be as shown in Equation 5.

[0086] [Equation 5]

[0087]

[0088] ZLC represents the characteristic impedance of the resonant circuit, L(f) represents the inductance at frequency f, C(f) represents the capacitance at frequency f, and w0 represents each frequency. The dispersion of impedance can be controlled by adjusting the L value of the inductor and the C value of the capacitor. When the frequency changes, the resonant circuit can disperse the impedance on the constant resistance circle on the Smith chart 410. According to an embodiment of the present disclosure, the impedance value of the resonant circuit configured with a series inductor and a series capacitor can be as shown in Equation 6.

[0089] [Equation 6]

[0090]

[0091] ZLC represents the characteristic impedance of the resonant circuit, L(f) represents the inductance at frequency f, C(f) represents the capacitance at frequency f, and w0 represents each frequency. The dispersion of impedance can be controlled by adjusting the L value of the inductor and adjusting the C value of the capacitor. When the frequency changes, the resonant circuit can disperse the impedance on the constant resistance circle on the Smith chart 410.

[0092] According to an embodiment, the resonant circuit impedance 405 Z depends on the resonant circuit structure. res The parallel resonant circuit impedance 411 Z may be included res-shynt And the series resonant circuit impedance 413 Z res-series , the parallel resonant circuit impedance is 411Z res-shunt is the impedance of the network circuit of the inductor and capacitor connected in parallel, the impedance of the series resonant circuit is 413 Z res-series is the impedance when the inductor and capacitor are connected in series. When the frequency changes, the impedance of the parallel resonant circuit 411 Z res-shunt Can be dispersed on a constant conductance circle, the impedance of the series resonant circuit is 413 Z res-series Can be dispersed on a constant resistance circle.

[0093] The first transmission line 403 can rotate the impedance. Like the transmission line input impedance 401 Z Tlin Similarly, the first transmission line 403 can rotate the parallel resonant circuit impedance 411Z shown in the Smith chart 410 res-shunt Or the impedance of the series resonant circuit is 413Z res-series trajectory.

[0094] Figure 5a An example of the impedance of the network circuit according to an embodiment of the present disclosure is shown. The network circuit may not include a resonant circuit. The network circuit may include a transmission line for impedance matching.

[0095] Figure 5b An example of the impedance of a network circuit including a resonant circuit according to an embodiment of the present disclosure is shown. The network circuit may include a resonant circuit and a transmission line for impedance matching. The transmission line may include a first region adjacent to the output of a Doherty power amplifier and a second region adjacent to a load impedance.

[0096] refer to Figure 5a , the communication circuit 500 may include a network circuit that does not include a resonant circuit. The network circuit may be coupled to a Doherty power amplifier. In the communication circuit 500, the load impedance 507 Z L Can be matched to the optimal impedance R opt To this end, the transmission line 505 can be connected to a load impedance 507 Z L Since the network circuit does not include a resonant circuit, the impedance ZL' of the network circuit can have a constant value even if the frequency changes.

[0097] Current impedance 501 Z prior The impedance observed from the input terminal of the first circuit in the communication circuit 500 may be represented. Distributed impedance 503 Z dis The network circuit may include a transmission line 505 and a load impedance 507Z. L For example, the element corresponding to the antenna corresponds to the load impedance Z L Optimum impedance R opt The value 513 may represent the impedance value of the network circuit to be matched.

[0098] refer to Figure 5b , the communication circuit 550 may include a network circuit including a resonant circuit 557. The network circuit may be coupled to a Doherty power amplifier. The network circuit may be coupled to a load impedance Z L The network circuit may include a first transmission line 556, a resonant circuit 557, and a second transmission line 558. Since the network circuit includes the resonant circuit 557, the impedance 555 Z′ of the network circuit is L The value of can change according to the frequency.

[0099] New Impedance 551 Z new The characteristic impedance from the main amplifier terminal for matching to the first circuit 552 for matching can be represented. Distributed impedance 553 Z disIt can represent the characteristic impedance from the network circuit to the first circuit 552. Carrier impedance 554 Z carrier It can represent the characteristic impedance from the first circuit 552 to the network circuit. Network impedance 555 Z′ L It can represent the characteristic impedance facing the network circuit from the output terminal of the Doherty power amplifier. The network circuit may include a transmission line 556, a resonant circuit 557, a transmission line 558, and a load impedance Z L In the peak amplifier, the second circuit 559 is used for output matching. Peak impedance 560 Z peaking The characteristic impedance facing the network circuit from the second circuit 559 can be represented.

[0100] Conjugate Distributed Impedance 571 Z dis *Can be distributed impedance 553 Z dis Conjugate impedance. Conjugate distributed impedance 571Z dis *Can be dispersed according to frequency, as shown in Smith chart 570.

[0101] In the Smith chart 510, due to the characteristics of the matching circuit, the existing impedance 501 Z prior Dispersed impedance 503 Z dis The conjugate complex number Z * dis Dispersion and network impedance Z′ L The degree of mismatch between them and a matching loss occurs.

[0102] The existing impedance is 511 Z prior In the case of dispersion, the existing impedance is 511 Z pripr may become different from the optimum impedance R opt The value is 513, so a matching loss may occur. Due to this matching loss, the performance of the Doherty power amplifier may become different from the design target.

[0103] Distributed impedance 553 Z dis and carrier impedance 554 Z carrier It can be determined by the current ratio β between the carrier amplifier and the peak amplifier and the current phase difference between the carrier amplifier and the peak amplifier at the coupling point. This is expressed as the following equation. Δθ(f) has a value obtained by subtracting the current phase of the main amplifier from the current phase of the auxiliary amplifier at the center frequency, and can be a variable modeled as a linear function dependent on frequency.

[0104] [Equation 7]

[0105] Δθ(f)=θ P (f)-θ C (f) = k3 (ff 0 )+θ 30

[0106] [Equation 8]

[0107]

[0108] [Equation 9]

[0109] Z pecking =(1+βe Δθ(f) )Z L '

[0110] According to an embodiment of the present disclosure, in the conjugate distributed impedance Z * dis In order to solve the conjugate distributed impedance Z in the case of frequency dispersion * dis and the optimum impedance R opt The matching loss between , needs to provide a characteristic impedance that depends on the frequency. The rotating network circuit according to the embodiment of the present disclosure can provide a carrier impedance Z that is dispersed clockwise according to the frequency carrier .

[0111] Figure 6 A functional configuration of a network circuit configured with a transmission line and a resonance circuit according to an embodiment of the present disclosure is shown.

[0112] refer to Figure 6 , the first transmission line module 601 is a transmission line having an electrical length. The resonant circuit block 603 is a resonant circuit of dispersive impedance. The second transmission line module 605 is a transmission line having an electrical length. In the following, by Figure 7 Detailed examples of the first transmission line module 601 or the second transmission line module 605 are described. Figure 8a , 8b and 9 describe a detailed example of the resonant circuit block 603.

[0113] Figure 7 An example of a transmission line included in a network circuit according to an embodiment of the present disclosure is shown.

[0114] refer to Figure 7 , the communication circuit 700 shows an example of a transmission line. The transmission line 701 may be a transmission line having a characteristic impedance Z 0 and a transmission line of electrical length θ.

[0115] According to one embodiment, the transmission line structure 703 may represent a low-pass filter structure implemented as an equivalent circuit in the form of a π network. In other words, the transmission line structure 703 may be an LCL filter in the form of a π network. The transmission line structure 703 may include one capacitor and two inductors.

[0116] According to one embodiment, the transmission line structure 705 may represent a high pass filter structure implemented as an equivalent circuit in the form of a π network. In other words, the transmission line structure 705 may be a CLC filter in the form of a π network. The transmission line structure 705 may include one inductor and two capacitors.

[0117] According to one embodiment, the transmission line structure 707 may represent a low-pass filter structure implemented as an equivalent circuit in the form of a T network. In other words, the transmission line structure 707 may be an LCL filter in the form of a T network. The transmission line structure 707 may include one capacitor and two inductors.

[0118] According to one embodiment, the transmission line structure 709 may represent a high pass filter structure implemented as an equivalent circuit in the form of a T network. In other words, the transmission line structure 709 may be a CLC filter in the form of a T network. The transmission line structure 709 may include one capacitor and two inductors.

[0119] According to an embodiment, in the case where the transmission line 701 is implemented by lumped elements (e.g., inductors, capacitors) as in the above-mentioned equivalent circuit diagram, at least some of the lumped elements may be connected to another block (e.g., Figure 6 The lumped elements of the resonant circuit block 603) are merged. By merging, the implementation of the circuit can be simplified.

[0120] Figure 8a An example of a Doherty power amplifier circuit including a resonant circuit using a stub according to an embodiment of the present disclosure is shown.

[0121] refer to Figure 8a , the communication circuit 800 may include a Doherty power amplifier 801 and a network circuit 803 for impedance matching. Figure 2a , 2b , 5a and 5b can be applied to the Doherty power amplifier 801 in the same or similar manner. When impedance matching is used for band extension of the Doherty power amplifier 801, a network circuit 803 can be used. The network circuit 803 can include a transmission line 805, a resonant circuit and a transmission line 807. The resonant circuit of the network circuit 803 can include a short circuit 809 and an open circuit 811.

[0122] The resonant circuit may include a 1 and electrical length θ 1 The short circuit 809 has a characteristic impedance R 1 and electrical length 90-θ 1 The transmission line 805 may have an open circuit 811.0 The characteristic impedance and θ 2 The transmission line 807 may have an electrical length of Z 0 Characteristic impedance and 90-θ 2 The electrical length.

[0123] Figure 8b An example of a Doherty power amplifier circuit including a resonant circuit using lumped elements according to an embodiment of the present disclosure is shown.

[0124] refer to Figure 8b , the communication circuit 850 may include a Doherty power amplifier 851 and a network circuit 853 for impedance matching. Figure 2a , 2b The description of the Doherty power amplifier described in Figures 5a and 5b can be applied to the Doherty power amplifier 851 in the same or similar manner.

[0125] When impedance matching is used for band extension of Doherty power amplifier 851, network circuit 853 may be used. Network circuit 853 may include transmission line 855, resonant circuit 859, and transmission line 857. Resonant circuit 859 of network circuit 853 may include lumped elements. According to an embodiment, resonant circuit 859 may include lumped elements. According to an embodiment, resonant circuit 859 may include an inductor and a capacitor connected in series. Transmission line 855 may have Z 0 The characteristic impedance and θ 2 The transmission line 857 may have an electrical length of Z 0 Characteristic impedance and 90-θ 2 The electrical length.

[0126] Fig. 9 An example of a resonance circuit included in a network circuit according to an embodiment of the present disclosure is shown.

[0127] refer to Fig. 9 , the communication circuit 900 shows an example of a resonant circuit. The resonant circuit 901 means a circuit having a frequency selection characteristic. Since the difference between the inductance component and the capacitance component of the resonant circuit 901 at the resonant frequency is balanced, resonance may occur in the resonant circuit 901.

[0128] According to an embodiment, the resonant circuit structure 903 may have a structure in which a short-circuited stub and an open-circuited stub are connected in parallel. The short-circuited stub R1∠θ1 and the open-circuited stub R1∠90-θ1 may be arranged in parallel between an input port (eg, port 1) and an output port (eg, port 2).

[0129] The resonant circuit structure 903 may have a structure having a characteristic impedance R1 and electrical length θ 1 The short-circuited stub has a characteristic impedance R 1 and electrical length 90-θ 1 As described above, the impedance Z of the resonant circuit configured with the short-circuited stub and the open stub is LC is equal to Equation 4. In Equation 4, θ 1 It can be expressed as Equation 10.

[0130] [Equation 10]

[0131] θ 1 (f) = k 1 (ff 10 )+θ 10

[0132] θ 1 It can represent the electrical length of the transmission line. 1 It can express the degree of phase change according to the transmission line frequency. 10 It can represent the center frequency. 10 It can be expressed as the electrical length at the center frequency.

[0133] According to an embodiment, the resonant circuit structure 905 may be a structure in which an inductor and a capacitor are connected in parallel. The inductor L1 may be provided in parallel between an input port (e.g., port 1) and an output port (e.g., port 2). The capacitor C1 may be provided in parallel between an input port (e.g., port 1) and an output port (e.g., port 2). For example, the impedance Z of the resonant circuit LC Please refer to the above equation 5.

[0134] According to an embodiment, the resonant circuit structure 907 may be a structure in which an inductor and a capacitor are connected in series. The inductor L1 may be provided in series between an input port (eg, port 1) and an output port (eg, port 2). For example, the impedance Z of the resonant circuit is LC Refer to the above equation 6.

[0135] According to an embodiment, the resonant circuit structure 909 may have a structure in which a short-circuited stub that rotates impedance like an inductor is connected in parallel with a capacitor. The short-circuited stub R1∠θ1 may be arranged in parallel between an input port (e.g., port 1) and an output port (e.g., port 2). The short-circuited stub may provide an inductive load. The capacitor C1 may be arranged in parallel between an input port (e.g., port 1) and an output port (e.g., port 2).

[0136] According to an embodiment, the resonant circuit structure 911 may have a structure in which an open stub that rotates impedance like a capacitor is connected in parallel with an inductor. The inductor L1 may be arranged in parallel between an input port (e.g., port 1) and an output port (e.g., port 2). The open stub R1∠90-θ1 may be arranged in parallel between an input port (e.g., port 1) and an output port (e.g., port 2). The open stub may provide a capacitive load.

[0137] According to an embodiment, in the case where a transmission line is implemented by lumped elements (e.g., inductors, capacitors) similar to the above-mentioned equivalent circuits, at least some of the lumped elements may be connected to another block (e.g., Figure 6 The lumped elements of the first transmission line block 601 are merged. By merging, the implementation of the circuit can be simplified.

[0138] Fig.10a An example of a network circuit including a transmission line and a resonant circuit according to an embodiment of the present disclosure is shown.

[0139] refer to Fig.10a , the communication circuit 1000 shows an example of a network circuit. The communication circuit 1010 shows a circuit configured with a first transmission line 1011, a resonant circuit 1013, a second transmission line 1015, and a load impedance Z L network circuit.

[0140] According to an embodiment, the network circuit structure 1030 shows a network circuit including a first transmission line 1031, a resonant circuit 1035 including a short-circuited stub, an open-circuited stub, and a second transmission line 1033. The short-circuited stub R1∠θ1 and the open-circuited stub R1∠90-θ1 may be disposed in parallel between the first transmission line 1031 and the second transmission line 1033.

[0141] The structure of the resonant circuit 1035 may be a structure having a characteristic impedance R 1 and electrical length θ 1 The short-circuited stub has a characteristic impedance R 1 and electrical length 90-θ 1 As described above, the impedance Z of the resonant circuit configured with the short-circuited stub and the open stub is LC is equal to equation 4.

[0142] According to an embodiment, the network circuit structure 1050 shows a network circuit including a first transmission line 1051, a resonance circuit 1055 in which an inductor and a capacitor are connected in parallel, and a second transmission line 1053. The inductor L1 may be disposed in parallel between the first transmission line 1051 and the second transmission line 1053. The capacitor C1 may be disposed in parallel between the first transmission line 1051 and the second transmission line 1053. For example, the impedance Z of the resonance circuit LC Please refer to the above equation 5.

[0143] According to an embodiment, the network circuit structure 1070 shows a network circuit including a first transmission line 1071, a resonant circuit 1075 in which an inductor and a capacitor are connected in series, and a second transmission line 1073. The inductor L1 may be arranged in series between the first transmission line 1071 and the second transmission line 1073. The capacitor C1 may be arranged in series between the first transmission line 1071 and the second transmission line 1073. For example, the impedance Z of the resonant circuit LC Refer to the above equation 6.

[0144] exist Fig.10a The position of the resonant circuit set on the transmission line is constant, and θ 2 The value is shown as being constant, but the embodiments of the present disclosure are not limited thereto. In the case where the resonant circuit is configured with a lumped element, as the position of the resonant circuit on the transmission line having an electrical length of 90 degrees changes, the θ of the transmission line 2 The value may change. In this case, θ can be determined by simulation 2 value to make the best match.

[0145] Fig.10b is an equivalent circuit diagram according to an embodiment of the present disclosure, in which some lumped elements in the equivalent circuit of the transmission line and some lumped elements in the equivalent circuit of the resonant circuit are combined in a network circuit.

[0146] refer to Fig.10b The circuit diagram 1020 of the network circuit may include a first transmission line 1021, a resonant circuit 1023, a second transmission line 1025, and a load impedance Z L . The first transmission line 1021 may be an LCL filter in the form of a π network. The resonant circuit 1023 may be configured with a resonant circuit structure 905 in which an inductor and a capacitor are connected in parallel. In the circuit diagram 1040 which is an equivalent circuit diagram of the circuit diagram 1020, components of the inductor 1022 and the inductor 1024 may be combined to be configured with one inductor. When the network circuit is implemented using only lumped elements, the circuit structure may be simplified by using appropriate structures of the transmission line and the resonant circuit.

[0147] Despite Fig.10bAlthough not shown in the figure, in the resonant circuit, the circuit in which the inductor and the capacitor are connected in series can be an equivalent circuit of the circuit in which the inductor and the capacitor are connected in parallel and a transmission line having an electrical length of 90 degrees is added. Therefore, according to the selection of the resonant circuit structure, the degree of dispersion and rotation of the impedance can be controlled without adding a separate transmission line.

[0148] Fig.11 An example of a Doherty power amplifier and network circuit according to an embodiment of the present disclosure is shown.

[0149] refer to Fig.11 , the communication circuit 1100 shows a Doherty power amplifier and a network circuit. Circuit portion 1101 may represent a power divider. Circuit portion 1102 may represent a phase compensation circuit. Circuit portion 1103 may represent a carrier amplifier. Circuit portion 1104 may represent a peak amplifier. Circuit portion 1105 may represent a network circuit. The design frequency band of the communication circuit 1100 is 3.4-3.8 GHz. In the following, Fig.12a , 12b , 13a, 13b and 13c, it can be confirmed whether the performance of the amplifier is improved based on whether the present disclosure is implemented.

[0150] Fig.12a The effect of improving the power gain of the Doherty power amplifier through the network structure according to the embodiment of the present disclosure is shown.

[0151] Reference Fig.12a , a graph 1201 represents a gain value of a Doherty power amplifier coupled to a transmission line for impedance matching. The graph 1201 may represent power gains of five frequencies from 3.4 GHz to 3.8 GHz at intervals of 100 MHz in the Doherty power amplifier. The horizontal axis of the graph 1201 represents output power (unit: decibel milliwatt (dBm)), and the vertical axis of the graph 1201 represents gain (unit: decibel (dB)).

[0152] Graph 1202 represents the gain performance of a Doherty power amplifier coupled to a network circuit for rotation of dispersed impedance according to an embodiment of the present disclosure. Graph 1202 may represent the power gain of five frequencies spaced 100 MHz from 3.4 GHz to 3.8 GHz in the Doherty power amplifier.

[0153] In the graph 1202, it is confirmed that the power gain is generally increased in a specific frequency band (e.g., 3.4 GHz to 3.7 GHz). As the overall gain increases, the range of the frequency band that can be used also increases. Through the network circuit for rotating the impedance through dispersion, the Doherty power amplifier can support a wide band.

[0154] Figure 12b The effect of improving the drain efficiency of the Doherty power amplifier through the network structure according to the embodiment of the present disclosure is shown.

[0155] Reference Figure 12b , a graph 1251 represents a drain efficiency value of a Doherty power amplifier coupled to a transmission line for impedance matching. The graph 1251 may represent drain efficiency values ​​of five frequencies with an interval of 100 MHz from 3.4 GHz to 3.8 GHz in the Doherty power amplifier. The horizontal axis of the graph 1251 represents output power (unit: decibel milliwatt (dBm)), and the vertical axis of the graph 1251 represents drain efficiency (unit: percentage (%)).

[0156] Graph 1252 represents the drain efficiency value of the Doherty power amplifier coupled to the network circuit for rotating the impedance through dispersion according to an embodiment of the present disclosure. Graph 1252 may represent the drain efficiency values ​​of five frequencies spaced 100 MHz from 3.4 GHz to 3.8 GHz in the Doherty power amplifier. The horizontal axis of graph 1252 represents output power (unit: decibel milliwatt (dBm)), and the vertical axis of graph 1252 represents drain efficiency (unit: percentage (%)).

[0157] In graph 1252 , it can be confirmed that the overall drain efficiency increases.

[0158] Fig.13a An example of a power gain of a Doherty power amplifier in an average power region for each frequency based on whether a network circuit is added according to an embodiment of the present disclosure is shown.

[0159] Reference Fig.13a , graph 1300 shows the power gain of the Doherty power amplifier in the average power region for each frequency based on whether a network circuit is added according to an embodiment of the present disclosure. Graph 1300 may represent the power gain of the Doherty power amplifier in the average power region for five frequencies with an interval of 100 MHz from 3.4 GHz to 3.8 GHz. The horizontal axis of graph 1300 represents the frequency (unit: gigahertz (GHz)), and the vertical axis of graph 1300 represents the power gain in the average power region (unit: decibel (dB)). The black curve may represent the power gain of the Doherty power amplifier coupled to the transmission line for impedance matching. The white curve may represent the power gain of the Doherty power amplifier in the average power region for each frequency when the network circuit for the rotation of the impedance through dispersion is combined.

[0160] It can be confirmed that the power gain of the power amplifier including the network matching circuit based on impedance rotation according to the embodiment is greater than the power gain of the conventional power amplifier. Through the large power gain, the possible frequency band is expanded. The network circuit for rotating the impedance through dispersion according to the embodiment can provide a frequency band expansion effect.

[0161] Fig.13b The maximum output power at each frequency of the Doherty power amplifier according to the embodiment of the present disclosure based on whether a network circuit is added is shown.

[0162] Reference Fig.13b , graph 1310 shows the maximum output power of the Doherty power amplifier for each frequency based on whether the network circuit according to the embodiment of the present disclosure is added. Graph 1310 can represent the maximum output power of the Doherty power amplifier for five frequencies with an interval of 100 MHz from 3.4 GHz to 3.8 GHz. The horizontal axis of graph 1310 represents the frequency (unit: gigahertz (GHz)), and the vertical axis of graph 1310 represents the maximum output power (Psat) (unit: decibel milliwatt (dBm)). The black curve can represent the maximum output power of each frequency of the Doherty power amplifier coupled to the transmission line for impedance matching. The white curve can represent the maximum output power of each frequency of the Doherty power amplifier coupled to the network circuit for the rotation of the impedance through dispersion.

[0163] It can be confirmed that the maximum output power of the power amplifier including the network circuit for rotating the impedance through dispersion according to the embodiment is greater than the maximum output power of the conventional power amplifier. Through the high maximum output power, the possible frequency band is extended. The network circuit for rotating the impedance through dispersion according to the embodiment can provide a frequency band extension effect.

[0164] Fig.13c The drain efficiency at the maximum output power of each frequency of the Doherty power amplifier according to an embodiment of the present disclosure based on whether a network circuit is added is shown.

[0165] Reference Fig.13c, graph 1320 shows the drain efficiency of the Doherty power amplifier in the maximum output power region for each frequency based on whether a network circuit is added according to an embodiment of the present disclosure. Graph 1320 may represent the drain efficiency of the Doherty power amplifier in the maximum output power region for five frequencies with an interval of 100 MHz from 3.4 GHz to 3.8 GHz. The horizontal axis of graph 1320 represents the frequency (unit: gigahertz (GHz)), and the vertical axis of graph 1320 represents the drain efficiency in the maximum output power region (unit: percentage (%)). The black curve may represent the drain efficiency at the maximum output power of each frequency of the Doherty power amplifier coupled to the transmission line for impedance matching. The white graph may represent the drain efficiency in the maximum output power region of each frequency of the Doherty power amplifier coupled to the network circuit for rotation of the dispersed impedance.

[0166] It can be confirmed that the drain efficiency of the power amplifier including the network circuit for rotating the impedance through dispersion according to the embodiment is greater than the drain efficiency of the conventional power amplifier. Through the high drain efficiency, the possible frequency band is extended. The network circuit for rotating the impedance through dispersion according to the embodiment can provide a frequency band extension effect.

[0167] Fig.13d The drain efficiency at the average output power at each frequency of the Doherty power amplifier according to an embodiment of the present disclosure based on whether a network circuit is added is shown.

[0168] Reference Fig.13d , graph 1330 shows the drain efficiency of the Doherty power amplifier in the average output power region for each frequency according to whether a network circuit is added, which is an embodiment of the present disclosure. Graph 1330 may represent the drain efficiency of the Doherty power amplifier in the average output power region for five frequencies with an interval of 100 MHz from 3.4 GHz to 3.8 GHz. The horizontal axis of graph 1330 represents the frequency (unit: gigahertz (GHz)), and the vertical axis of graph 1320 represents the drain efficiency in the average output power region (unit: percentage (%)). The black curve may represent the drain efficiency in the average output power region of each frequency of the Doherty power amplifier, which does not include a network circuit for rotation of the dispersed impedance. The white curve may represent the drain efficiency in the average output power region of each frequency of the Doherty power amplifier including a network circuit for rotation of the dispersed impedance.

[0169] It can be confirmed that the drain efficiency of the power amplifier including the network circuit for rotating the impedance through dispersion according to the embodiment at the average output power is greater than the drain efficiency of the conventional power amplifier at the average output power. The possible frequency band is extended by the drain efficiency at the high average output power. The network circuit for rotating the impedance through dispersion according to the embodiment can provide a frequency band extension effect.

[0170] A Doherty power amplifier according to an embodiment of the present disclosure may include a matching network circuit that is implemented in a simpler manner than a Doherty power amplifier that fixes the load impedance and uses a multi-stage circuit. By adjusting the length of the resonant circuit and the transmission line, the degree of impedance dispersion and the degree of rotation can be controlled. By providing a controlled impedance to the load network of the carrier amplifier and the peak amplifier, the circuit structure for matching is simplified. Therefore, performance such as maximum output power, efficiency, linearity, etc. in a wider frequency band is improved. The matching network circuit according to an embodiment of the present disclosure can minimize power consumption and heat generation by minimizing matching losses in a wireless communication system. Minimizing power consumption and heat generation leads to improved performance of the entire wireless communication system.

[0171] The device and method according to the embodiment of the present disclosure can control the dispersion degree and rotation degree of impedance by adjusting the length of the transmission line in the resonant circuit and the network circuit. By providing controlled impedance to the load network of the carrier amplifier and the peak amplifier, the circuit structure for matching is simplified. In addition, performance such as maximum output power, efficiency, linearity, etc. in a wider frequency band can be improved.

[0172] As described above, according to an embodiment, an electronic device including a Doherty power amplifier may include a carrier amplifier, a first circuit coupled to an output terminal of the carrier amplifier, a peak amplifier, a second circuit coupled to the output terminal of the peak amplifier, and a network circuit. The network circuit may include a Doherty power amplifier and a transmission line for impedance matching with a resonant circuit. The resonant circuit may be arranged between a first region and a second region of the transmission line. In the electronic device, the Doherty power amplifier may provide an output impedance within a first range based on a frequency distribution within a bandwidth, and the network circuit may provide a load impedance. The network circuit may provide a load impedance within a second range based on a frequency distribution within a bandwidth. The first region of the transmission line may provide a first phase shift impedance to reduce the difference between the output impedance within the first range and the load impedance within the second range. The second region of the transmission line may provide a second phase shift impedance.

[0173] According to an embodiment, the resonance circuit may include a first transmission line constituted by a short circuit and a second transmission line constituted by an open circuit.

[0174] According to an embodiment, the resonance circuit may include an inductor and a capacitor connected in series.

[0175] According to an embodiment, the resonance circuit may include an inductor and a capacitor connected in parallel.

[0176] According to an embodiment, the transmission line may be a microstrip.

[0177] According to an embodiment, a transmission line may include capacitors and inductors arranged in a π-type.

[0178] According to an embodiment, a transmission line may include a capacitor and an inductor in a T-type arrangement.

[0179] According to an embodiment, the load impedance within the second range may be provided by applying the first phase-shift impedance to the dispersion impedance of the resonance circuit based on the frequency distribution within the bandwidth.

[0180] According to an embodiment, the first region of the transmission line rotates the dispersion impedance of the resonant circuit on the Smith chart to reduce the difference between the dispersion impedance of the resonant circuit and the output impedance in the first range by the first phase shift impedance.

[0181] According to an embodiment, the resonant circuit may be variably disposed between a first region and a second region of the transmission line. When the resonant circuit is in the first position, the first phase-shift impedance may be a first value, and the second phase-shift impedance may be a second value. When the resonant circuit is in the second position, the first phase-shift impedance may be a third value different from the first value, and the second phase-shift impedance may be a fourth value different from the second value. The sum of the first value and the second value may be equal to the sum of the third value and the fourth value.

[0182] As described above, a radio frequency integrated circuit (RFIC) according to an embodiment may include a plurality of radio frequency (RF) processing chains. Each of the plurality of RF processing chains may include a phase shifter and a Doherty power amplifier. The Doherty power amplifier may include a carrier amplifier, a first circuit coupled to an output terminal of the carrier amplifier, a peak amplifier, a second circuit coupled to an output terminal of the peak amplifier, and a network circuit. The network circuit may include a transmission line for impedance matching with a resonant circuit and a Doherty power amplifier. In an electronic device, the resonant circuit may be arranged between a first region and a second region of the transmission line. The Doherty power amplifier may provide an output impedance within a first range based on a frequency distribution within a bandwidth, and the network circuit may provide a load impedance. The network circuit may provide a load impedance within a second range based on a frequency distribution within a bandwidth. The first region of the transmission line may provide a first phase shift impedance to reduce the difference between the output impedance within the first range and the load impedance within the second range. The second region of the transmission line may provide a second phase shift impedance.

[0183] According to an embodiment, the resonance circuit may include a first transmission line formed by a short circuit and a second transmission line formed by an open circuit.

[0184] According to an embodiment, the resonant circuit may include an inductor and a capacitor connected in series.

[0185] According to an embodiment, the resonant circuit may include an inductor and a capacitor connected in parallel.

[0186] According to an embodiment, the transmission line may be a microstrip.

[0187] According to an embodiment, a transmission line may include capacitors and inductors arranged in a π shape.

[0188] According to an embodiment, a transmission line may include a capacitor and an inductor in a T-type arrangement.

[0189] According to an embodiment, the load impedance within the second range may be provided by applying the first phase-shift impedance to the dispersion impedance of the resonance circuit based on the frequency distribution within the bandwidth.

[0190] According to an embodiment, the first region of the transmission line may rotate the dispersion impedance of the resonance circuit on the Smith chart to reduce the difference between the dispersion impedance of the resonance circuit and the output impedance within the first range by the first phase shift impedance.

[0191] According to an embodiment, the resonant circuit may be variably disposed between the first region and the second region of the transmission line. When the resonant circuit is in the first position, the first phase-shift impedance may be a first value, and the second phase-shift impedance may be a second value. When the resonant circuit is in the second position, the first phase-shift impedance may be a third value different from the first value, and the second phase-shift impedance may be a fourth value different from the second value. The sum of the first value and the second value may be equal to the sum of the third value and the fourth value.

[0192] The methods according to the embodiments described in the claims or the specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

[0193] When implemented as software, a computer-readable storage medium storing one or more programs (software modules) may be provided. One or more programs stored in the computer-readable storage medium are configured to be executed by one or more processors in an electronic device. One or more programs include instructions that cause the electronic device to perform the method according to the embodiments described in the claims or description of the present disclosure.

[0194] Such a program (software module, software) may be stored in a random access memory, a non-volatile memory including flash memory, a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a magnetic disk storage device, a compact disk-ROM (CD-ROM), a digital versatile disk (DVD) or other form of optical storage, a cassette tape. Alternatively, it may be stored in a memory configured with some or all of these combinations. Furthermore, each configured memory may include multiple.

[0195] In addition, the program can be stored in an attachable storage device, which can be accessed through a communication network, such as the Internet, an intranet, a local area network (LAN), a wide area network (WAN) or a storage area network (SAN) or a combination thereof. Such a storage device can be connected to the equipment performing the disclosed embodiment through an external port. In addition, an independent storage device on a communication network can access the equipment performing the disclosed embodiment.

[0196] In the above specific embodiments of the present disclosure, the components included in the present disclosure are expressed in the singular or plural, depending on the specific embodiments presented. However, for ease of explanation, singular or plural expression is appropriately selected for the presented situation, and the present disclosure is not limited to singular or plural components, and even if the component is expressed in plural, it can be configured in the singular, or even if it is expressed in the singular, it can be configured in the plural.

[0197] While the present disclosure has been shown and described with reference to various embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents.

Claims

1. An electronic device comprising a Doherty power amplifier, the electronic device comprising: Carrier amplifier; a first circuit coupled to an output terminal of the carrier amplifier; Peaking amplifier; a second circuit coupled to an output terminal of the peak amplifier; as well as Network circuits, Wherein, the network circuit includes the Doherty power amplifier and a transmission line for impedance matching with the resonant circuit, wherein the resonant circuit is arranged between the first region and the second region of the transmission line, wherein the Doherty power amplifier provides an output impedance within a first range based on a frequency distribution within a bandwidth, wherein the network circuit provides a load impedance within a second range based on the frequency distribution within the bandwidth, wherein the first region of the transmission line provides a first phase shift impedance to reduce a difference between the output impedance within the first range and the load impedance within the second range, and The second region of the transmission line provides a second phase shift impedance.

2. The electronic device according to claim 1, wherein: The resonant circuit includes a first transmission line formed by a short circuit and a second transmission line formed by an open circuit.

3. The electronic device according to any one of claims 1 to 2, wherein: The resonant circuit includes an inductor and a capacitor connected in series.

4. The electronic device according to any one of claims 1 to 3, wherein: The resonant circuit includes an inductor and a capacitor connected in parallel.

5. The electronic device according to any one of claims 1 to 4, wherein: The transmission line is a microstrip.

6. The electronic device according to any one of claims 1 to 5, wherein: The transmission line includes capacitors and inductors arranged in a π-type.

7. The electronic device according to any one of claims 1 to 6, wherein: The transmission line includes a capacitor and an inductor in a T-type arrangement.

8. The electronic device according to any one of claims 1 to 7, wherein: The load impedance within the second range is provided by applying the first phase-shift impedance to a dispersion impedance of the resonant circuit based on the frequency distribution within the bandwidth.

9. The electronic device according to any one of claims 1 to 8, wherein: The first region of the transmission line rotates the dispersion impedance of the resonant circuit on a Smith chart to reduce a difference between the dispersion impedance of the resonant circuit and the output impedance within the first range by the first phase-shift impedance.

10. The electronic device according to any one of claims 1 to 9, in, The resonant circuit is variably disposed between the first region and the second region of the transmission line, wherein, when the resonant circuit is in a first position, the first phase-shift impedance is a first value, and the second phase-shift impedance is a second value, wherein, when the resonant circuit is in the second position, the first phase-shifted impedance is a third value different from the first value, and the second phase-shifted impedance is a fourth value different from the second value, and The sum of the first value and the second value is equal to the sum of the third value and the fourth value.

11. A radio frequency integrated circuit (RFIC) in a wireless communication system, the RFIC comprising: Multiple RF processing chains, Each of the plurality of RF processing chains comprises a phase shifter and a Doherty power amplifier, Wherein, the Doherty power amplifier comprises: Carrier amplifier, a first circuit, coupled to an output terminal of the carrier amplifier, Peaking amplifier, a second circuit coupled to an output terminal of the peak amplifier, and Network circuits, Wherein, the network circuit comprises a transmission line for impedance matching with the resonant circuit and the Doherty power amplifier, wherein the resonant circuit is arranged between the first region and the second region of the transmission line, wherein the Doherty power amplifier provides an output impedance within a first range based on a frequency distribution within a bandwidth, wherein the network circuit provides a load impedance within a second range based on the frequency distribution within the bandwidth, wherein the first region of the transmission line provides a first phase shift impedance to reduce a difference between the output impedance within the first range and the load impedance within the second range, and The second region of the transmission line provides a second phase shift impedance.

12. The RFIC according to claim 11, wherein: The resonant circuit includes a first transmission line formed by a short circuit and a second transmission line formed by an open circuit.

13. The RFIC according to any one of claims 11 to 12, wherein: The resonant circuit includes an inductor and a capacitor connected in series.

14. The RFIC according to any one of claims 11 to 13, wherein: The resonant circuit includes an inductor and a capacitor connected in parallel.

15. The RFIC according to any one of claims 11 to 14, wherein: The transmission line is a microstrip.

Images