Efficient transmitter and communication equipment

Abstract

The invention discloses a high-efficiency transmitter and communication equipment, the high-efficiency transmitter comprises a power amplifier and an impedance conversion assembly connected with the output end of the power amplifier, and the impedance conversion assembly is used as load impedance to maintain the output power and linear index of the high-efficiency transmitter and improve the efficiency; wherein if the load of the output end of the power amplifier when the output end of the power amplifier is not connected with the impedance conversion assembly is marked as the original load, the output impedance of the output end of the power amplifier after the output end of the power amplifier is connected with the impedance conversion assembly is positive integer multiples of the original load. According to the embodiment of the invention, the impedance conversion technology is adopted, and the output current of the power amplifier is reduced by changing the impedance of the output port of the power amplifier under the condition that the output power and the input voltage are not changed, so that the power amplifier ensures the linearity and the power amplifier efficiency is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of radio communication systems, and in particular to a high-efficiency transmitter and communication equipment. Background Art

[0002] With the development of radio communication systems, new modulation forms are constantly being used, the peak-to-average ratio is continuously increasing, and the transmitter needs to improve efficiency while maintaining linearity. However, wideband and narrowband radio products generally still use the power back-off method, which leads to low efficiency of RF power amplifiers.

[0003] For example, currently commonly used modulation methods include Figure 1 The envelope separation and recovery technology shown in the circuit diagram in the figure is to decompose the input signal into phase and amplitude information (specifically, the decomposition is performed through a coupler). The phase is controlled by a nonlinear power amplifier, and the amplitude information controls the power amplifier (i.e. Figure 1 The advantage of the envelope separation and recovery technology is that the RF power amplifier always works in a more efficient switching mode state, but its accuracy and performance change with time and temperature, and the introduction of nonlinear devices increases the distortion products. At the same time, its application in the RF field is not mature yet.

[0004] Common modulation methods include Figure 2 The Linc technology (the full name of Linc is Linear Amplifier Using Nonlinear Components, which is a technology that uses nonlinear power amplifiers to achieve linear amplification of signals) shown in the circuit diagram in the figure is to decompose the signal and pass it through a high-efficiency amplifier (i.e. Figure 2 middle One path is a high efficiency amplifier), and the other path is phase-converted (i.e. Figure 2 middle The circuit is a phase conversion circuit) and the final output is synthesized. Although the efficiency that can be achieved in theory is relatively high, the signal is easily distorted.

[0005] Common modulation methods include Figure 3 The Doherty technology (a technology that uses load modulation technology to improve back-off efficiency) shown in the circuit diagram in FIG. Figure 3 Carrier / Main) works in Class AB (i.e., a combination of Class A and Class B amplifiers that depends on the bias current and output level) or Class B (also known as Class B power amplifier, also known as linear amplifier), peak power amplifier work (i.e. Figure 3Peaking / Auxiliary) in Class C (i.e. Class C amplifier, power amplifier with conduction angle less than 180 degrees is called Class C amplifier), it only starts working when it reaches the set peak value, and finally outputs through the impedance matching network. Because two power amplifiers are used, the implementation cost is high and the area is large; and under the high peak-to-average ratio, the efficiency improvement is limited compared with the traditional AB class (the efficiency improvement is 11-14% after testing).

[0006] Common modulation methods include Figure 4 The feedforward technology (also known as feedforward cancellation technology) shown in the circuit diagram in the figure separates the distortion signal from the power amplifier signal, then amplifies the distortion signal in reverse phase, and then combines it with the main signal to cancel the original distortion component, which not only achieves the purpose of improving linearity. It also indirectly improves the efficiency of the transmitter system. However, in the feedforward technology, feedforward cancellation requires two loops, one loop extracts the distortion component (that is, the loop where the MPA power amplifier is located), and the other loop amplifies the distortion component for cancellation (that is, the loop where the EPA power amplifier is located). Both loops need to be debugged in amplitude, phase, and delay, and the circuit structure is complex and debugging is extremely difficult. In addition, two power amplifier links are required in the feedforward. When the control performance of the two links is consistent and the phase is opposite, the implementation cost is high. Summary of the invention

[0007] The present invention provides a high-efficiency transmitter and communication equipment, aiming to solve the problem of complex circuit structure and high implementation cost in the modulation form adopted by the transmitter in the prior art in order to maintain linearity while improving efficiency.

[0008] In a first aspect, the present invention proposes a high-efficiency transmitter, comprising a power amplifier and an impedance transformation component connected to the output end of the power amplifier, wherein the impedance transformation component is used as a load impedance to improve efficiency while maintaining the output power and linearity indicators of the high-efficiency transmitter; wherein, if the load of the output end of the power amplifier when the impedance transformation component is not connected is recorded as the original load, then the output impedance of the output end of the power amplifier after the impedance transformation component is connected is a positive integer multiple of the original load.

[0009] According to an embodiment of the present application, the impedance transformation component is a single impedance transformation line.

[0010] According to an embodiment of the present application, the single impedance transformation line is a λ / 4 impedance transformer.

[0011] According to an embodiment of the present application, the impedance transformation component includes a plurality of impedance transformation lines, and the plurality of impedance transformation lines are connected in series.

[0012] According to an embodiment of the present application, the impedance transformation component includes a plurality of impedance transformation lines, and the plurality of impedance transformation lines are connected in parallel.

[0013] According to an embodiment of the present application, each of the plurality of impedance transformation lines is a λ / 4 impedance transformer.

[0014] According to one embodiment of the present application, the impedance transformation component is a balun.

[0015] According to one embodiment of the present application, the impedance conversion component includes a first single-pole multi-throw switch, a multi-channel impedance converter and a second single-pole multi-throw switch; the input end of the first single-pole multi-throw switch is connected to the output end of the power amplifier, and each of the multiple output ends of the first single-pole multi-throw switch is connected to one end of one of the impedance converters in the multi-channel impedance converter; the other end of each impedance converter in the multi-channel impedance converter is connected to one of the multiple input ends of the second single-pole multi-throw switch.

[0016] According to an embodiment of the present application, each impedance converter in the multi-channel impedance converter is any one of a single impedance conversion line, a plurality of impedance conversion lines connected in series, a plurality of impedance conversion lines connected in parallel, and a balun.

[0017] In a second aspect, the present invention further proposes a communication device, comprising the high-efficiency transmitter of any one of the above-mentioned first aspects.

[0018] Compared with the prior art, the present invention provides a high-efficiency transmitter and communication equipment, wherein the high-efficiency transmitter includes a power amplifier and an impedance conversion component connected to the output end of the power amplifier, wherein the impedance conversion component is used as a load impedance to maintain the output power and linearity index of the high-efficiency transmitter while improving efficiency; wherein, if the load of the output end of the power amplifier when the impedance conversion component is not connected is recorded as the original load, the output impedance of the output end of the power amplifier after the impedance conversion component is connected is a positive integer multiple of the original load. The embodiment of the present invention adopts impedance conversion technology, and when the output power and input voltage remain unchanged, the output current of the power amplifier is reduced by changing the impedance of the output port of the power amplifier, so that the power amplifier can achieve a significant improvement in power amplifier efficiency while ensuring linearity. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0020] Figure 1A schematic diagram of the circuit structure of the envelope separation and restoration technology provided in the prior art;

[0021] Figure 2 A schematic diagram of the circuit structure of the Linc technology provided in the prior art;

[0022] Figure 3 A schematic diagram of the circuit structure of the Doherty technology provided in the prior art;

[0023] Figure 4 A schematic diagram of the circuit structure of the feedforward cancellation technology provided in the prior art;

[0024] Figure 5 A schematic block diagram of a high-efficiency transmitter provided in accordance with an embodiment of the present invention;

[0025] Figure 6 A schematic circuit diagram of an impedance transformation component according to the first embodiment used in a high-efficiency transmitter provided by an embodiment of the present invention;

[0026] Figure 7 A schematic circuit diagram of an impedance conversion component according to the second embodiment used in a high-efficiency transmitter provided by an embodiment of the present invention;

[0027] Figure 8 A schematic circuit diagram of an impedance transformation component according to the third embodiment used in a high-efficiency transmitter provided by an embodiment of the present invention;

[0028] Fig. 9 A schematic circuit diagram of an impedance transformation component according to the fourth embodiment used in a high-efficiency transmitter provided by an embodiment of the present invention;

[0029] Fig.10 The present invention is a schematic circuit diagram of an impedance transformation component according to the fifth embodiment used in a high-efficiency transmitter provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] The directional terms mentioned in the present invention, such as "upper", "lower", "front", "back", "left", "right", "inner", "outer", "side", etc., are only referenced to the directions of the attached drawings. Therefore, the directional terms used are used to illustrate and understand the present invention, but are not used to limit the present invention. In addition, in the drawings, structures with similar or identical structures are represented by the same reference numerals.

[0032] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0033] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, the singular forms "a", "an" and "the" are intended to include plural forms unless the context clearly indicates otherwise.

[0034] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0035] See also Figure 5 , which is a schematic block diagram of a high-efficiency transmitter provided by an embodiment of the present invention. Figure 5 As shown, an embodiment of the present invention provides a high-efficiency transmitter, comprising: a power amplifier 10 and an impedance transformation component 20 connected to the output end of the power amplifier 10, wherein the impedance transformation component 20 is used as a load impedance to improve efficiency while maintaining the output power and linearity indicators of the high-efficiency transmitter; wherein, if the load 30 of the output end of the power amplifier when the impedance transformation component is not connected is recorded as the original load, then the output impedance of the output end of the power amplifier after the impedance transformation component is connected is a positive integer multiple of the original load.

[0036] In this embodiment, the high-efficiency transmitter may use only one power amplifier 10, and the output end of the power amplifier 10 is connected to an impedance conversion component 20 to change the output end impedance. For example, if the output end of the power amplifier 10 is not connected to the impedance conversion component, the connected load 30 is recorded as the original load R0. First, the power amplifier efficiency under power back-off is analyzed. At this time, the power amplifier 10 is regarded as a voltage-controlled current source (its DC voltage is recorded as V DC ), when the input signal voltage swing is reduced by K times (K is a positive integer), the output signal current swing is also reduced by K times, and the load is still R0. In the current case:

[0037]

[0038] If the DC voltage of the power amplifier 10 is still V when it is regarded as a voltage-controlled current source DC , and the DC current is reduced by K times, then:

[0039]

[0040] in, It represents the efficiency when the output end of the power amplifier 10 is not connected to the impedance conversion component. From the expression, we can see that after the power amplifier 10 is backed off by K times, the efficiency will become If K=2, it means the power is backed off by 6 dB and the efficiency is lost by 50%. After the output end of the power amplifier 10 is connected to the impedance conversion component, the output impedance is KR0 (indicating a positive integer multiple of R0). In this case:

[0041]

[0042]

[0043] in, It represents the efficiency when the output end of the power amplifier 10 is connected to an impedance transformation component and the output impedance corresponding to the impedance transformation component is K times that of the original load R0. Through the above analysis, it can be concluded that when the load impedance of the original load R0 is increased by K times after impedance transformation, the efficiency loss caused by the back-off power is compensated by K times, and there is no loss in efficiency. When the high-efficiency transmitter is used with a high peak-to-average ratio, the power and linear indicators remain unchanged, and the efficiency is effectively and greatly improved. On the one hand, the high-efficiency transmitter is applicable whether it is used to transmit broadband signals or narrowband signals. On the other hand, connecting the impedance transformation component after the power amplifier is simple and easy to operate, has low implementation cost, small circuit area and convenient debugging.

[0044] In one embodiment, as a first embodiment of the impedance transformation component, as Figure 5-Figure 6 As shown, the impedance transformation component 20 is a single impedance transformation line.

[0045] In this embodiment, the impedance transformation component 20 is a single impedance transformation line 21, that is, the load impedance of the power amplifier 10 is pulled to a high impedance state through a single impedance transformation line 21. When the power and linear indicators of the power amplifier 10 remain unchanged, the efficiency of the power amplifier 10 is effectively and greatly improved.

[0046] In specific tests, such as Figure 6As shown, the power amplifier 10 uses a class AB amplifier, the single impedance transformation line 21 is an impedance line of 70.7Ω, and the original load is recorded as R0. When the bias current of the power amplifier 10 at the maximum power is detected to be 0.17A, the efficiency of the power amplifier 10 is 83.928%. When the power amplifier 10 uses a class AB amplifier and the impedance transformation component 20 is not connected thereto, the efficiency of the power amplifier 10 is 69.82%. It can be seen that the test results of pulling the load impedance of the power amplifier to a high impedance state through a single impedance transformation line show that the efficiency of the power amplifier is greatly improved when the power and linearity indicators of the power amplifier remain unchanged.

[0047] In one embodiment, the single impedance transformation line is a λ / 4 impedance transformer.

[0048] In this embodiment, the λ / 4 impedance converter can be understood as a single-section λ / 4 impedance converter composed of three transmission lines with impedances of Z1, Z2 and Z3. Moreover, in the order of Z1, Z2 and Z3, the impedance increases successively. The length of the λ / 4 impedance converter is one quarter of the wavelength (the wavelength refers to the wavelength of the signal in the high-efficiency transmitter). The λ / 4 impedance converter can achieve good impedance matching within a certain frequency range. Compared with other complex matching networks, it reduces the number of components and layout complexity, and reduces the equipment cost and manufacturing difficulty.

[0049] In one embodiment, as a second embodiment of the impedance transformation component, as Figure 5 and Figure 7 As shown, the impedance transformation component 20 includes a plurality of impedance transformation lines 22, and the plurality of impedance transformation lines 22 are connected in series.

[0050] In this embodiment, the impedance transformation component 20 includes a plurality of impedance transformation lines 22 connected in series to pull the load impedance of the power amplifier 10 to a high impedance state, and the efficiency of the power amplifier 10 is effectively and greatly improved while the power and linearity indicators of the power amplifier 10 remain unchanged. The impedance parameters of each impedance transformation line in the plurality of impedance transformation lines can be adjusted and changed according to the actual application scenario to meet the requirements of optimizing the efficiency indicator.

[0051] In specific tests, such as Figure 7As shown, the power amplifier 10 adopts a class AB amplifier, and the impedance transformation component 20 includes multiple impedance transformation lines 22, which are specifically 50Ω impedance lines 221 and 35Ω impedance lines 222 connected in series in sequence, and the original load is recorded as R0. When the bias current of the power amplifier 10 at the maximum power is detected to be 0.177A, the efficiency of the power amplifier 10 is 78.332%. When the power amplifier 10 adopts a class AB amplifier and the impedance transformation component 20 is not connected thereafter, the efficiency of the power amplifier 10 is 69.82%. It can be seen that the test results of pulling the load impedance of the power amplifier to a high impedance state through multiple impedance transformation lines connected in series show that the efficiency of the power amplifier is greatly improved when the power and linearity indicators of the power amplifier remain unchanged.

[0052] In one embodiment, as a third embodiment of the impedance transformation component, as Figure 5 and Figure 8 As shown, the impedance transformation component 20 includes a plurality of impedance transformation lines 23, and the plurality of impedance transformation lines 23 are connected in parallel.

[0053] In this embodiment, the multiple impedance transformation lines 23 included in the impedance transformation component 20 are connected in parallel to pull the load impedance of the power amplifier 10 to a high impedance state, and the efficiency of the power amplifier 10 is effectively and greatly improved when the power and linearity indicators of the power amplifier 10 remain unchanged. The impedance parameters of each impedance transformation line in the multiple impedance transformation lines can also be adjusted and changed according to the actual application scenario to meet the requirements of optimizing the efficiency indicator.

[0054] In the specific test, the power amplifier 10 adopts a class AB amplifier, and the multiple impedance transformation lines 23 included in the impedance transformation component 20 are specifically a 50Ω impedance line 231 and a 35Ω impedance line 232 connected in parallel, and the original load is recorded as R0. When the bias current of the power amplifier 10 at the maximum power is detected to be 0.156A, the efficiency of the power amplifier 10 is 84.944%. When the power amplifier 10 adopts a class AB amplifier and the impedance transformation component 20 is not connected thereafter, the efficiency of the power amplifier 10 is 69.82%. It can be seen that the test results of pulling the load impedance of the power amplifier to a high impedance state through multiple impedance transformation lines connected in parallel show that the efficiency of the power amplifier is greatly improved when the power and linear indicators of the power amplifier remain unchanged.

[0055] In one embodiment, in the second embodiment and the third embodiment of the impedance transformation component, each impedance transformation line in the plurality of impedance transformation lines is a λ / 4 impedance transformer.

[0056] In this embodiment, in the second embodiment and the third embodiment of the impedance transformation component, no matter the multiple impedance transformation lines are connected in series or in parallel, each of the multiple impedance transformation lines is a λ / 4 impedance transformer. Moreover, similar to the case where a single impedance transformation line is a λ / 4 impedance transformer in the first embodiment of the impedance transformation component, the λ / 4 impedance transformer will not be described in detail here.

[0057] In one embodiment, as a fourth embodiment of the impedance transformation component 20, as shown in FIG. Figure 5 and Fig. 9 As shown, the impedance transformation component 20 is a balun 24 .

[0058] In this embodiment, the balun 24 is also called a balanced and unbalanced impedance converter. As a three-port device, it has the following three main functions: first, it converts the current and voltage from an unbalanced state to a balanced state, that is, it converts the single-ended signal into a differential signal; second, it suppresses the common-mode current through certain structures; third, it converts the impedance of the front and rear stages through changes in the physical structure. The balun in this application is an impedance conversion balun, which can achieve impedance matching, DC isolation, and matching of balanced ports and single-ended ports. The impedance conversion balun pulls the load impedance of the power amplifier 10 to a high impedance state. When the power and linear indicators of the power amplifier 10 remain unchanged, the efficiency of the power amplifier 10 is effectively and greatly improved.

[0059] In the specific test, the power amplifier 10 uses a class AB amplifier, the balun in the impedance conversion component 20 is a 70.7Ω impedance conversion balun, and the original load is recorded as R0. When the bias current of the power amplifier 10 at the maximum power is detected to be 0.177A, the efficiency of the power amplifier 10 is 78.276%. When the power amplifier 10 uses a class AB amplifier and the impedance conversion component 20 is not connected afterwards, the efficiency of the power amplifier 10 is 69.82%. It can be seen that the test results of pulling the load impedance of the power amplifier to a high impedance state through the balun show that the efficiency of the power amplifier is greatly improved when the power and linear indicators of the power amplifier remain unchanged.

[0060] In one embodiment, as a fifth embodiment of the impedance transformation component 20, as shown in FIG. Figure 5 and Fig.10As shown, the impedance transformation component 20 includes a first single-pole multi-throw switch K1, a multi-channel impedance converter 25 and a second single-pole multi-throw switch K2; the input end of the first single-pole multi-throw switch K1 is connected to the output end of the power amplifier 10, and each of the multiple output ends of the first single-pole multi-throw switch K1 is connected to one end of one of the impedance converters in the multi-channel impedance converter; the other end of each impedance converter in the multi-channel impedance converter is connected to one of the multiple input ends of the second single-pole multi-throw switch K2.

[0061] In this embodiment, the output end of the second single-pole multi-throw switch K2 is connected to the load R0. In order to realize that the load impedance of the power amplifier 10 is pulled to a high impedance state in a multiple-choice manner, both ends of the multi-channel impedance converter 25 (a plurality of impedance converters connected in parallel) can be connected to the single-pole multi-throw switch. Specifically, when the first single-pole multi-throw switch K1 selects one of the multi-channel impedance converters, the second single-pole multi-throw switch K2 also selects the same one so that the impedance converter is selected and turned on. It can be seen that each impedance converter in the multi-channel impedance converter can adopt different impedance conversion forms, and then each impedance converter in the multi-channel impedance converter is designed in parallel and the path is selected through the single-pole multi-throw switch, and the user can select one of the paths according to actual use requirements.

[0062] In one embodiment, if Fig.10 As shown, each impedance converter in the multi-channel impedance converter 25 is any one of a single impedance conversion line, a plurality of impedance conversion lines connected in series, a plurality of impedance conversion lines connected in parallel, and a balun.

[0063] In this embodiment, since the multi-channel impedance converter is adopted, the user's selection diversity is increased. Therefore, when the user is actually using it, the control signal can be sent based on the control circuit so that when the first single-pole multi-throw switch K1 selects one of the multi-channel impedance converters, the second single-pole multi-throw switch K2 also selects the same one so that the impedance converter of the one channel is selected and turned on. Moreover, each impedance converter in the multi-channel impedance converter 25 is any one of a single impedance conversion line, a plurality of impedance conversion lines connected in series, a plurality of impedance conversion lines connected in parallel, and a balun. More specifically, among the four impedance converters in the multi-channel impedance converter, the first one is a single impedance conversion line, the second one is a plurality of impedance conversion lines connected in series, the third one is a plurality of impedance conversion lines connected in parallel, and the fourth one is a balun. In the above example, each impedance converter in the multi-channel impedance converter can pull the load impedance of the power amplifier to a high impedance state. Under the condition that the power and linearity indicators of the power amplifier remain unchanged, the efficiency of the power amplifier is effectively and greatly improved.

[0064] Another embodiment of the present application provides a communication device, which includes the above-mentioned high-efficiency transmitter. After the high-efficiency transmitter is used on the communication device, under the application of high peak-to-average ratio, the power and linear indicators remain unchanged, and the efficiency is effectively and greatly improved. On the one hand, the high-efficiency transmitter in the communication device is applicable whether it is used to transmit broadband signals or to transmit narrowband signals. On the other hand, connecting an impedance conversion component after the power amplifier is simple and easy to operate, has low implementation cost, small circuit area and convenient debugging.

[0065] In summary, the present invention provides a high-efficiency transmitter and communication equipment, wherein the high-efficiency transmitter includes a power amplifier and an impedance conversion component connected to the output end of the power amplifier, wherein the impedance conversion component is used as a load impedance to maintain the output power and linearity index of the high-efficiency transmitter while improving efficiency; wherein, if the load of the output end of the power amplifier when the impedance conversion component is not connected is recorded as the original load, the output impedance of the output end of the power amplifier after the impedance conversion component is connected is a positive integer multiple of the original load. The embodiment of the present invention adopts impedance conversion technology, and when the output power and input voltage remain unchanged, the output current of the power amplifier is reduced by changing the impedance of the output port of the power amplifier, so that the power amplifier can achieve a significant improvement in power amplifier efficiency while ensuring linearity.

[0066] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A high efficiency transmitter, characterized in that: It includes a power amplifier and an impedance conversion component connected to the output end of the power amplifier, wherein the impedance conversion component is used as a load impedance to improve efficiency while maintaining the output power and linearity index of the high-efficiency transmitter; wherein, if the load of the output end of the power amplifier when not connected to the impedance conversion component is recorded as the original load, the output impedance of the output end of the power amplifier after connecting the impedance conversion component is a positive integer multiple of the original load.

2. The high-efficiency transmitter according to claim 1, characterized in that The impedance transformation component is a single impedance transformation line.

3. The high-efficiency transmitter according to claim 2, characterized in that The single impedance transformation line is a λ / 4 impedance transformer.

4. The high-efficiency transmitter according to claim 1, characterized in that The impedance transformation component includes a plurality of impedance transformation lines, and the plurality of impedance transformation lines are connected in series.

5. The high-efficiency transmitter according to claim 1, characterized in that The impedance transformation component includes a plurality of impedance transformation lines, and the plurality of impedance transformation lines are connected in parallel.

6. The high-efficiency transmitter according to claim 4 or 5, characterized in that: Each of the plurality of impedance transformation lines is a λ / 4 impedance transformer.

7. The high-efficiency transmitter according to claim 1, characterized in that The impedance transformation component is a balun.

8. The high-efficiency transmitter according to claim 1, characterized in that The impedance transformation component includes a first single-pole multi-throw switch, a multi-channel impedance converter and a second single-pole multi-throw switch; the input end of the first single-pole multi-throw switch is connected to the output end of the power amplifier, and each of the multiple output ends of the first single-pole multi-throw switch is connected to one end of one of the impedance converters in the multi-channel impedance converter; the other end of each impedance converter in the multi-channel impedance converter is connected to one of the multiple input ends of the second single-pole multi-throw switch.

9. The high-efficiency transmitter according to claim 8, characterized in that Each impedance converter in the multi-channel impedance converter is any one of a single impedance conversion line, a plurality of impedance conversion lines connected in series, a plurality of impedance conversion lines connected in parallel, and a balun.

10. A communication device, characterized in that: Comprising a high efficiency transmitter as claimed in any one of claims 1-9.

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