KR20140084861A - Doherty amplifier with smaller size and extended bandwidth - Google Patents

Doherty amplifier with smaller size and extended bandwidth Download PDF

Info

Publication number
KR20140084861A
KR20140084861A KR1020120154824A KR20120154824A KR20140084861A KR 20140084861 A KR20140084861 A KR 20140084861A KR 1020120154824 A KR1020120154824 A KR 1020120154824A KR 20120154824 A KR20120154824 A KR 20120154824A KR 20140084861 A KR20140084861 A KR 20140084861A
Authority
KR
South Korea
Prior art keywords
amplifier
auxiliary
amplifying unit
load impedance
main
Prior art date
Application number
KR1020120154824A
Other languages
Korean (ko)
Inventor
양영구
서민철
Original Assignee
성균관대학교산학협력단
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 성균관대학교산학협력단 filed Critical 성균관대학교산학협력단
Priority to KR1020120154824A priority Critical patent/KR20140084861A/en
Publication of KR20140084861A publication Critical patent/KR20140084861A/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/02—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation
    • H03F1/0205—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in transistor amplifiers
    • H03F1/0288—Modifications of amplifiers to raise the efficiency, e.g. gliding Class A stages, use of an auxiliary oscillation in transistor amplifiers using a main and one or several auxiliary peaking amplifiers whereby the load is connected to the main amplifier using an impedance inverter, e.g. Doherty amplifiers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/56—Modifications of input or output impedances, not otherwise provided for
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/60—Amplifiers in which coupling networks have distributed constants, e.g. with waveguide resonators
    • H03F3/602—Combinations of several amplifiers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F2200/00—Indexing scheme relating to amplifiers
    • H03F2200/543—A transmission line being used as coupling element between two amplifying stages

Abstract

A small Doherty amplifier with an extended bandwidth according to embodiments of the present invention comprises a main amplifying unit; an auxiliary amplifying unit; a load impedance modulating unit which is connected between output nodes of each of the main amplifying unit and the auxiliary amplifying unit to provide the main amplifying unit with load impedance modulated according to the operation of the auxiliary amplifying unit; and a harmonic control matching circuit unit which performs impedance matching of a reference frequency and at least one harmonic component of a signal component in the output nodes of the auxiliary amplifying unit.

Description

[0001] DOHERTY AMPLIFIER WITH SMALLER SIZE AND EXTENDED BANDWIDTH [0002]

The present invention relates to a power amplifier, and more particularly, to a Doherty amplifier.

Recent wireless data communications such as OFDM typically involve a high peak-to-average power ratio (PAPR), such as using a very large number of subcarriers rather than a single carrier to convey a large amount of information.

Meanwhile, a high output amplifier (HPA) used in a base station or the like is saturated at an output higher than a specific level defined by an input back-off (IBO) and an output back-off (OBO) to cause nonlinear distortion. The nonlinear characteristics of a high - power amplifier are represented by phase shift, attenuation, offset, and distortion of the received signal, and spectral radiation occurs outside the frequency band.

Therefore, in order to reduce the nonlinear distortion at the output, it is necessary to reduce the PARP of the input signal or enlarge the linear operation section of the high-power amplifier.

Clipping, filtering, encoding, scrambling of the symbol input sequence, and DFT (Discrete Fourier Transform) spreading are used to reduce the PARP of the input signal. Doherty, LINC, Envelope Elimination and Restoratin (EIN), and Bias Adaptation technique have been proposed to expand the linear operation range of the high power amplifier.

The proposed Doherty amplifier in the 1930s was originally a carrier amplifier (or main amplifier) for the carrier component and a peaking amplifier (or auxiliary amplifier) for the signal component to achieve high efficiency at the same time . The configuration of the two amplifiers can be different depending on the characteristics of the amplifier. In this case, impedance matching problems and power combining problems that can occur in this case can be solved by a load modulation technique.

In the Doherty amplifier, the peaking amplifier operates in Class B or Class C, distortion occurs, and the bias can be adjusted so that this distortion is offset from the distortion of the carrier amplifier.

However, since at least two amplification paths are required, the size of the amplifying device is increased, and the carrier amplifier operates in the class A or AB, which has disadvantages such as power consumption and heat problems.

However, when a large number of subcarriers such as OFDM are used, the advantage of a Doherty amplifier that separately provides an amplification path for signal components in addition to a carrier wave, a structure for maintaining efficiency and bandwidth while reducing the size and power consumption of the Doherty amplifier Is required.

A problem to be solved by the present invention is to provide a compact Doherty amplifier having an extended bandwidth.

A Doherty amplifier according to one aspect of the present invention is a Doherty amplifier having a main amplifier and an auxiliary amplifier,

A load impedance modulator connected between each of the output nodes of the main amplifying unit and the auxiliary amplifying unit to provide the main amplifying unit with the load impedance modulated according to the operation of the auxiliary amplifying unit; And

And a harmonic control matching circuit unit for impedance-matching the reference frequency of the signal component and at least one harmonic component at the output nodes of the auxiliary amplifier unit.

According to one embodiment, the harmonic control matching circuitry

A first microstrip line and a stub pair for impedance-matching a reference frequency of a signal component; And

And a second microstrip line and a stub pair for impedance-matching the second harmonic of the signal component,

The first and second microstrip lines and stub pairs may be connected in series.

According to one embodiment, the load impedance modulating unit comprises:

A microstrip line connected between each of the output nodes of the main amplifying unit and the auxiliary amplifying unit, and a radial stub branched at both ends of the microstrip line.

According to one embodiment, the load impedance modulating unit comprises:

An inductor connected between the output nodes of the main amplifying unit and the auxiliary amplifying unit, and a radial stub branched at both ends of the inductor.

According to one embodiment, the load impedance modulating unit comprises:

And an inductor connected between each of the output nodes of the main amplifying unit and the auxiliary amplifying unit, and a radial stub and a capacitor branched from both ends of the inductor.

According to one embodiment, the load impedance modulating unit comprises:

Network may be formed of a microstrip line connected between each of the output nodes of the main amplifying unit and the auxiliary amplifying unit, and a radial stub and a capacitor branched at both ends of the microstrip line.

According to one embodiment, the load impedance modulating unit may further include auxiliary matching circuits for further providing an insufficient impedance component.

According to one embodiment, it may further comprise a? / 4 line connecting the DC power supply voltage to the output node of the main amplifier.

A first? / 4 line connecting a first DC power supply voltage to an output node of the main amplifying unit, according to an embodiment; And

And a second? / 4 line for connecting a second DC power supply voltage to an output node of the auxiliary amplifying unit.

According to one embodiment, the load impedance modulating unit comprises:

And a coupling capacitor coupling the first and second DC voltages between the first? / 4 line and the second? / 4 line.

According to the compact Doherty amplifier having the extended bandwidth of the present invention, by applying a radial stub to the conventional Doherty amplifier, it is possible to suppress the size increase while enlarging the bandwidth without requiring a complicated additional circuit.

According to the small-sized Doherty amplifier having the extended bandwidth of the present invention, the harmonic control circuit can be applied even in the peaking amplifier path, thereby maintaining the linearity within a wide bandwidth and improving the efficiency.

1 is a block diagram illustrating a compact Doherty amplifier having an extended bandwidth using a harmonic control matching circuit in accordance with an embodiment of the present invention.
Figures 2 and 3 are block diagrams illustrating a compact Doherty amplifier with extended bandwidth according to various embodiments of the present invention.

For the embodiments of the invention disclosed herein, specific structural and functional descriptions are set forth for the purpose of describing an embodiment of the invention only, and it is to be understood that the embodiments of the invention may be practiced in various forms, The present invention should not be construed as limited to the embodiments described in Figs.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

1 is a block diagram illustrating a compact Doherty amplifier having an extended bandwidth using a harmonic control matching circuitry in accordance with an embodiment of the present invention.

The extended band compact Doherty amplifier 1 may include a main amplifier 10, an auxiliary amplifier 20, a load impedance modulator 30, a lambda / 4 line 40 and a harmonic control matching circuit 50 have.

The main amplifying unit 10 and the auxiliary amplifying unit 20 amplify carriers and signal components with high power, respectively, and are biased with different bias voltages. In addition, the linearity can be increased and the efficiency can be improved through adaptive bias control.

The load impedance modulating unit 30 connects the output node of the main amplifying unit 10 and the output node of the auxiliary amplifying unit 20 and changes the gain according to the operation of the auxiliary amplifying unit 20 to the main amplifying unit 10 ), Thereby enabling the asymmetric power coupling at the output stage while maintaining the gain of the entire Doherty amplifier 1 constant.

The load impedance modulating unit 30 is implemented in the form of a π-network composed of a microstrip line 31 and two radial stubs 32 and 33. In accordance with the operation of the auxiliary amplifying unit 20, 10 viewed load impedance of the auxiliary amplifier in the section 20 to provide a variable characteristic impedance R T that causes variation to 2R 0 when not in operation, the auxiliary amplifier section 20 at R 0 at the time of operating up to .

The load impedance modulation section 30 of the present invention can eliminate the matching circuit for the main amplification section 10 as compared with the conventional structure in which the impedance modulation circuit is located next to the matching circuit so that the overall size of the amplifier can be reduced In addition, by using microstrip lines and radial stubs, it is possible to mass-produce compact and less design errors.

One of the two radial stubs 32 and 33 is connected in parallel to the output node of the main amplifying part 10 and the other radial stub 33 is connected in parallel to the output node of the auxiliary amplifying part 20. [ Lt; / RTI >

The radial stubs 32 and 33 can be designed to have a desired equivalent capacitive reactance Xc by adjusting the aperture angle and the outer radius.

Further, the microstrip line 31 can be designed to have a desired impedance R 0 ∠ &thgr; by adjusting its length and width.

The load impedance modulation section 30 adjusts the length and width of the microstrip line 31 and adjusts the opening angle and the radius of the radial stubs 32 and 33 so that any desired equivalent characteristic impedance R T (Not shown).

The equivalent characteristic impedance R T provided by the load impedance modulation section 30 can be expressed by the following equation (1).

Figure pat00001

According to the embodiment, the load impedance modulation section 30 can replace the microstrip line 31 with an inductor, and implement a? Network with the inductor and the radial stubs 32 and 33.

Furthermore, the load impedance modulating unit 30 can replace the radial stub of one of the two radial stubs 32 and 33 with a capacitor to realize a π network with the microstrip line 31 and the radial stub 32 and the capacitor .

The load impedance modulation section 30 substitutes one of the two radial stubs 32 and 33 with a capacitor and replaces the microstrip line 31 with an inductor so that the inductor and the radial stub 32, The network can be implemented.

On the other hand, the? / 4 line 40 is an impedance-matched line for providing the DC power source Vds to the main amplifying unit 10 and the auxiliary amplifying unit 20 expressed as one transistor in FIG.

Furthermore, the small Doherty amplifier 1 of the present invention is a small-sized Doherty amplifier 1 in which the main amplifier 10 and the auxiliary amplifier 20 amplify and combine the signal components according to the load impedance modulated by the load impedance modulator 30, The control matching circuit part 50 can match not only the fundamental frequency component of each of the carrier wave and the signal component but also the harmonics of the signal component so as to have the optimum impedance.

To this end, the harmonic control matching circuit unit 50 includes not only the pair of impedance-matched microstrip line 51a and stub 52a with respect to the fundamental frequency component of the signal component, but also the characteristic impedance and capacitance The microstrip lines 51b and 51c and the stubs 51b and 52c having the stray reactance.

According to an embodiment, the harmonic control matching circuitry 50 may similarly match for harmonics of the carrier wave.

Figures 2 and 3 are block diagrams illustrating a compact Doherty amplifier with extended bandwidth according to various embodiments of the present invention.

2, the extended band compact Doherty amplifier 2 includes a first λ / 4 line 41 and a second λ / 4 line 42 (see FIG. 2) ), And the load impedance modulation section 30a may further include a DC coupling capacitor 34. The DC-

The main amplifier unit 10 receives the power supply voltage Vds1 matched by the first? / 4 line 41 and the auxiliary amplifier unit 20 receives the power supply voltage Vds2 matched by the second? / 4 line 42 . Since the two DC voltages Vds1 and Vds2, which may have different values, are separated by the DC coupling capacitor 34, the main amplifier 10 and the auxiliary amplifier 20 can be biased to different bias voltages .

3, the extended-band small-size Doherty amplifier 3 may further include the auxiliary impedance matching circuits 35 and 36 in parallel with the radial stubs 32 and 33 in the load impedance modulation section 30b .

The auxiliary matching circuits 35 and 36 are provided with the reactance components X 1 and X 2 in addition to the radial stubs 32 and 33 in the load impedance modulation section 30b, It is possible to compensate the reactance component X 1 in the case where the radial stub 32 does not provide the requisite reactance or to add the reactance component X 1 in the case where the inductor 37 is adopted instead of the microstrip line 31 2 ). ≪ / RTI >

Further, the auxiliary matching circuits 35 and 36 may be matching circuits that serve to remove the harmonic components of the carrier, or to remove harmonics above a certain order with respect to the signal components.

3, the power supply voltage Vds may be provided to the output node of the auxiliary amplifier unit 20 via the inductor 43. In this case as well, the auxiliary matching circuit 36 may be a matching circuit which, together with the inductor 43, provides? / 4 impedance matching to the power supply voltage Vds.

Table 1 compares the performance of the extended band compact Doherty amplifier of the present invention with the conventional Doherty amplifier without the harmonic control circuit.

Referring to Table 1, under the same conditions of carrier frequency 751 MHz, the extended band small Doherty amplifier of the present invention has a gain of 17.6 dB at peak power, somewhat at 17.7 dB, compared with a conventional Doherty amplifier without harmonic control circuit Power-added efficiency (PAE) improved by 6.7% at peak power, 5.5% at P1dB, and 4.2% at 3 dB back-off, respectively. There is little difference in 6dB backoff and 9dB backoff.

Doherty amplifier The Doherty amplifier Difference Gain @ Peak 17.7dB 17.6dB -0.1dB PAE @ Peak 74.7% 81.4% + 6.7% PAE @ P1dB 74.7% 80.2% + 5.5% PAE @ 3dB Backoff 71.6% 75.8% + 4.2% PAE @ 6dB Backoff 67.5% 67.5% 0 PAE @ 9dB Backoff 55.5% 55% -0.5%

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, Modification is possible. Accordingly, the spirit of the present invention should be understood only in accordance with the following claims, and all of the equivalent or equivalent variations will fall within the scope of the present invention.

1 Extended-band compact Doherty amplifier
10 main amplifier section
20 auxiliary amplifier unit
30, 30a, 30b The load impedance modulation section
31 microstrip line
32, 33 Radial stub
34 DC Coupling Capacitor
35, 36 auxiliary matching circuit
40? / 4 line
50, 51 Harmonic control matching circuit

Claims (10)

In a Doherty amplifier having a main amplifier and an auxiliary amplifier,
A load impedance modulator connected between each of the output nodes of the main amplifying unit and the auxiliary amplifying unit to provide the main amplifying unit with the load impedance modulated according to the operation of the auxiliary amplifying unit; And
And a harmonic control matching circuit for impedance matching the reference frequency of the signal component and at least one harmonic component at the output nodes of the auxiliary amplifier. [3] The apparatus of claim 1, wherein the harmonic control matching circuit
A first microstrip line and a stub pair for impedance-matching a reference frequency of a signal component; And
And a second microstrip line and a stub pair for impedance-matching the second harmonic of the signal component,
Wherein the first and second microstrip lines and the stub pairs are connected in series. The load impedance modulator of claim 1,
Wherein the main amplifier and the auxiliary amplifier are formed in a π network composed of a microstrip line connected between each of the output nodes of the main amplifier and the auxiliary amplifier, and radial stubs branched from both ends of the microstrip line. The load impedance modulator of claim 1,
Wherein the main amplifier and the auxiliary amplifier are connected to each other through an inductor and a radial stub branched at both ends of the inductor. The load impedance modulator of claim 1,
And a π network formed by an inductor connected between each of the output nodes of the main amplifier and the auxiliary amplifier, and a radial stub and a capacitor branched from both ends of the inductor. The load impedance modulator of claim 1,
And a π network formed by a microstrip line connected between each of the output nodes of the main amplifier and the auxiliary amplifier, and a radial stub and a capacitor branched from both ends of the microstrip line. The Doherty amplifier according to any one of claims 4 to 6, wherein the load impedance modulator further comprises auxiliary matching circuits for further providing an insufficient impedance component. The Doherty amplifier of claim 1, further comprising a? / 4 line connecting a DC power supply voltage to an output node of the main amplifier. [2] The apparatus of claim 1, further comprising: a first? / 4 line connecting a first DC power supply voltage to an output node of the main amplifying unit; And
And a second? / 4 line connecting a second DC power supply voltage to an output node of the auxiliary amplifier. 10. The apparatus of claim 9, wherein the load impedance modulator comprises:
And a coupling capacitor coupling the first and second DC voltages between the first? / 4 line and the second? / 4 line.
KR1020120154824A 2012-12-27 2012-12-27 Doherty amplifier with smaller size and extended bandwidth KR20140084861A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020120154824A KR20140084861A (en) 2012-12-27 2012-12-27 Doherty amplifier with smaller size and extended bandwidth

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020120154824A KR20140084861A (en) 2012-12-27 2012-12-27 Doherty amplifier with smaller size and extended bandwidth

Publications (1)

Publication Number Publication Date
KR20140084861A true KR20140084861A (en) 2014-07-07

Family

ID=51734671

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020120154824A KR20140084861A (en) 2012-12-27 2012-12-27 Doherty amplifier with smaller size and extended bandwidth

Country Status (1)

Country Link
KR (1) KR20140084861A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20230007556A (en) * 2014-05-13 2023-01-12 스카이워크스 솔루션즈, 인코포레이티드 Systems and methods related to linear and efficient broadband power amplifiers

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20230007556A (en) * 2014-05-13 2023-01-12 스카이워크스 솔루션즈, 인코포레이티드 Systems and methods related to linear and efficient broadband power amplifiers

Similar Documents

Publication Publication Date Title
Kang et al. Design of bandwidth-enhanced Doherty power amplifiers for handset applications
US10298177B2 (en) N-way doherty distributed power amplifier with power tracking
EP2145385B1 (en) N-way doherty distributed power amplifier
US9496836B2 (en) Doherty amplifier
EP2388912B1 (en) Power control of reconfigurable outphasing Chireix amplifiers and methods
US8384475B2 (en) Composite amplifier, a radio terminal and a method for improving the efficiency of the composite amplifier
US8988147B2 (en) Multi-way Doherty amplifier
US20200274495A1 (en) Transformer-based doherty power amplifier
US20100253426A1 (en) High-Efficiency Power Amplifier
US20160142020A1 (en) Power amplifier for amplifying radio frequency signal
US20210021238A1 (en) Doherty power amplifier circuit
US10063190B2 (en) Broadband Doherty power amplifier
US20210218375A1 (en) Load modulated balanced power amplifier integrated circuits including transformer-based hybrid splitter/combiner circuits
KR20140084861A (en) Doherty amplifier with smaller size and extended bandwidth
CN112020826A (en) Amplifier with a high-frequency amplifier
Li et al. A broadband SiGe power amplifier in an efficient polar transmitter using envelope-tracking for mobile WiMAX
CN116647199B (en) Tuning transformer and Doherty power amplifier comprising same
Martelius et al. Spectral effects of discrete-time amplitude levels in digital-intensive wideband radio transmitters
JP7039826B2 (en) Doherty type amplifier
Sajedin et al. Modified Symmetric Three-stage Doherty Power Amplifier for 5G
Cijvat et al. A GaN HEMT power amplifier with variable gate bias for envelope and phase signals
Wang Doherty Architecture for mm-wave/RF Digital and Analog Power Amplifiers
Rao et al. Multi band Multi standard 50W high efficiency and highly linear Power Amplifier for Macro Base Stations
Mahoutı et al. DESIGN OF A HIGH EFFICIENCY POWER AMPLIFIER FOR WIRELESS AND RADAR APPLICATIONS
Singhal et al. Class-E PA efficiency enhancement using zero voltage switching contour control

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E601 Decision to refuse application