Radio frequency transmitter

Abstract

The invention discloses a radio frequency transmitter. The radio frequency transmitter comprises at least one main array and at least one impedance compensation array, the main array and the impedance compensation array are arranged in parallel; the main array comprises a plurality of basic units I, the impedance compensation array comprises a plurality of basic units II, the output ends of the basic units I are connected in parallel through a first signal line, and the output ends of the basic units II are connected in parallel through a second signal line; when the radio frequency transmitter works, X basic units I in the main array are opened, N-X basic units II in the impedance compensation array are opened, the opened basic units I in the main array work in response to a baseband control code, and the opened basic units II in the impedance compensation array work in response to a complementary signal of the baseband control code; and the impedance generated by the main array and the impedance generated by the impedance compensation array are mutually offset in a non-linear manner. Factors causing nonlinearity of a circuit can be eliminated fundamentally, the digital transmitter has the advantages of being insensitive to process corner, temperature, voltage and frequency changes, and the digital transmitter with high linearity, high robustness and broadband can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of wireless communications, and in particular relates to a radio frequency transmitter. Background Art

[0002] Digital transmitters are gaining more and more attention due to their high efficiency, high integration, low cost, compatibility with digital chips such as baseband, flexible architecture, and direct conversion from baseband to RF modulated signals. However, due to factors such as the output impedance of digital transmitters changing with the control code, distributed parasitics, and local oscillator leakage, nonlinear distortion occurs, and the nonlinearity becomes more serious as the frequency increases.

[0003] Existing linearization technologies include digital pre-distortion (DPD) technology, open-loop linearization technology, on-chip automatic calibration technology, etc., but digital pre-distortion technology and open-loop linearization technology are not universally applicable to different frequencies, process angles, voltages, and temperature changes, and require more complex circuits (such as ADC, mixers, memories, linearization circuits, off-chip control, etc.). At the same time, nonlinear distortion will lead to a reduction in the effective bit position of the digital transmitter. In order to ensure the effective bit position, a higher bit position needs to be designed, resulting in additional hardware overhead and higher power consumption of the digital baseband. On-chip automatic calibration technology can achieve adaptive calibration at different frequencies, process angles, voltages, and temperatures through a real-time calibration loop, but it is difficult to achieve broadband modulation due to the loop response time. Therefore, the linearity of the digital transmitter needs to be further improved. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides a radio frequency transmitter. The technical problem to be solved by the present invention is achieved by the following technical solutions:

[0005] In a first aspect, the present invention provides a radio frequency transmitter, comprising:

[0006] at least one main array and at least one impedance compensation array; wherein,

[0007] The main array and the impedance compensation array are arranged in parallel; the main array includes N basic units 1 arranged in parallel, the impedance compensation array includes N basic units 2 arranged in parallel, the output ends of multiple basic units 1 are connected in parallel through a first signal line, the output ends of multiple basic units 2 are connected in parallel through a second signal line, and the first signal line and the second signal line are connected to a first node;

[0008] When the radio frequency transmitter is working, X basic unit ones in the main array are turned on, and NX basic unit twos in the impedance compensation array are turned on, and the number X of the turned-on basic unit ones in the main array works in response to the baseband control code, and the number NX of the turned-on basic unit twos in the impedance compensation array works in response to the complementary signal of the baseband control code, and the impedance output by the main array and the impedance output by the impedance compensation array are nonlinearly offset to maintain the output impedance of the first node constant.

[0009] Beneficial effects of the present invention:

[0010] The present invention provides a radio frequency transmitter, which introduces an impedance compensation array and is arranged in parallel with a main array. The output impedance of the main array and the output impedance of the impedance compensation array are nonlinearly offset, so that the output impedance of the first node is maintained constant. The digitally controlled impedance compensation array generates an output impedance that is opposite to the change trend of the main array impedance with the control code, so that the output impedance of the radio frequency transmitter will not change with the change of the number of basic units turned on, and the output impedance remains constant with the control code, thereby fundamentally eliminating the factors that cause circuit nonlinearity.

[0011] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of a digital pre-distortion technology in the prior art;

[0013] Figure 2 It is a schematic diagram of a loop self-calibration Polar digital transmitter in the prior art;

[0014] Figure 3 is a schematic diagram of a radio frequency transmitter provided by an embodiment of the present invention;

[0015] Figure 4 is another schematic diagram of a radio frequency transmitter provided by an embodiment of the present invention;

[0016] Figure 5 is a schematic diagram of a current source unit 1 in a current source array provided by an embodiment of the present invention;

[0017] Figure 6 is a schematic diagram of a current source unit 2 in an impedance-compensated current source array provided by an embodiment of the present invention;

[0018] Figure 7 is a schematic diagram of an equivalent circuit of a radio frequency transmitter provided by an embodiment of the present invention;

[0019] Figure 8 It is a schematic diagram of an equivalent circuit of a radio frequency transmitter in the prior art;

[0020] Fig. 9 is a comparative schematic diagram of the influence of the impedance compensation current source array provided by an embodiment of the present invention on the output impedance;

[0021] Fig.10 is a schematic diagram of a digital orthogonal transmitter architecture provided by an embodiment of the present invention;

[0022] Fig.11 is a schematic diagram of a digital polar transmitter architecture provided by an embodiment of the present invention;

[0023] Fig.12 It is a schematic diagram of the effect of impedance compensation provided by an embodiment of the present invention on output amplitude and output phase at different frequencies;

[0024] Fig.13 is a schematic diagram of an impedance change diagram provided by an embodiment of the present invention;

[0025] Fig.14 It is a schematic diagram of the influence of temperature and process angle on output amplitude and phase provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below with reference to specific embodiments, but the embodiments of the present invention are not limited thereto.

[0027] Existing digital pre-distortion linearity enhancement technologies include Figure 1 As shown, in order to improve the nonlinearity of the transmitter system, the nonlinearity of the transmitter is compensated in the digital domain in the reverse trend. In order to accurately obtain the distortion characteristics of the transmitter system, the transmission signal needs to be down-mixed, amplified, and ADC sampled, and then processed in the digital domain to obtain the compensated digital baseband signal; this solution requires complex off-chip circuits and multiple DPD solutions, and cannot be universally applied to different frequencies, process angles, voltages, and temperature changes.

[0028] Existing on-chip loop self-calibration Polar digital transmitters such as Figure 2 As shown, the output signal is compared with the reference signal through the phase detector to obtain the phase difference between the output and the ideal reference; the voltage Vphase containing the phase difference information is converted into a charging current Icharge through OTA to drive the capacitor storage array; the phase shifter is adjusted according to the value stored in the capacitor storage array to change the phase of the input local oscillator, thereby realizing the automatic calibration of the AM-PM distortion of the Polar architecture. Self-calibration technology can realize adaptive calibration at different frequencies, process angles, voltages, and temperatures through real-time calibration loops, but it is difficult to achieve broadband modulation due to the loop response time.

[0029] In summary, the existing digital pre-distortion linearity enhancement technology has the following defects:

[0030] 1. The system overhead is large, and additional down-mixing, amplifiers, ADC and other circuits are required to detect the signal;

[0031] 2. It is sensitive to PVT and needs to be recalibrated under different temperatures, process angles, and power supply conditions, resulting in poor robustness;

[0032] 3. It is sensitive to frequency. The same solution cannot be applied to different frequencies, and it is difficult to achieve broadband.

[0033] The existing loop self-calibration technology has the following defects:

[0034] 1. It only calibrates the phase of the Polar architecture, but cannot calibrate the amplitude, nor can it be applied to orthogonal transmitters;

[0035] 2. The loop response time will limit the modulation bandwidth.

[0036] In view of this, the present invention provides a radio frequency transmitter, which provides impedance compensation by setting an impedance compensation array, thereby achieving an unchanged output impedance of a digital transmitter, further achieving high linearity of the hardware itself, and supporting broadband high-order modulation without the need for digital pre-distortion; in addition, the impedance compensation provided by the present invention is insensitive to changes in process angle, temperature, voltage, and frequency, and has stronger robustness than traditional linearity enhancement technology (digital pre-distortion), and can achieve a wide bandwidth.

[0037] See also Figure 3 , Figure 3 is a schematic diagram of a radio frequency transmitter provided by an embodiment of the present invention. The radio frequency transmitter provided by the present invention comprises: at least one main array and at least one impedance compensation array; wherein,

[0038] The main array and the impedance compensation array are arranged in parallel; the main array includes N basic units 1 arranged in parallel, the impedance compensation array includes N basic units 2 arranged in parallel, the output ends of multiple basic units 1 are connected in parallel through a first signal line, the output ends of multiple basic units 2 are connected in parallel through a second signal line, and the first signal line and the second signal line are connected to a first node;

[0039] When the radio frequency transmitter is working, X basic units 1 in the main array are turned on, and NX basic units 2 in the impedance compensation array are turned on. The turned-on basic units 1 in the main array work in response to the baseband control code, and the turned-on basic units 2 in the impedance compensation array work in response to the complementary signal of the baseband control code. The impedance output by the main array and the impedance output by the impedance compensation array are nonlinearly offset, so that the output impedance of the first node is maintained constant.

[0040] For more details, please see Figure 3In a radio frequency transmitter provided in this embodiment, an impedance compensation array is connected in parallel outside a main array of the radio frequency transmitter, the main array is provided with N basic units 1 in parallel, and the impedance compensation array is provided with N basic units 2 in parallel, N is a constant, the basic units 1 in the main array are provided in parallel, and the basic units 2 in the impedance compensation array are provided in parallel, the output ends of the basic units 1 in the main array are connected in parallel through a first signal line, and the output ends of the basic units 2 in the impedance compensation array are connected in parallel through a second signal line, the first signal line and the second signal line are connected at a first node, and the output impedance of the main array and the output impedance of the impedance compensation array converge at the first node.

[0041] When the RF transmitter is working, X basic units 1 in the main array are turned on, and the corresponding NX basic units 2 in the impedance compensation array are turned on. The turned-on basic units 1 in the main array work in response to the baseband control code, and the turned-on basic units 2 in the impedance compensation array work in response to the complementary signal of the baseband control code. The impedance output by the main array and the impedance output by the impedance compensation array are nonlinearly offset, so that the output impedance of the first node remains constant. In the prior art, the number of turned-on basic units in the array of the RF transmitter is directly related to the baseband control code. The different number of turned-on basic units will directly affect the output impedance of the array, so that the output impedance of the RF transmitter changes with the control code. The characteristic that the output impedance of the array changes with the baseband control code causes its nonlinear distortion, and additional calibration technology is required to calibrate the linearity, such as digital pre-distortion technology. In addition, in the millimeter wave frequency band, due to the increase in frequency, the parasitic parameters of the layout, etc., the linearity is further deteriorated. It is difficult to achieve a high-linearity, digital pre-distortion-free digital transmitter in the millimeter wave frequency band. There is currently no such technology. A digital transmitter without digital predistortion that can support 256QAM and above high-order modulation broadband signals; the radio frequency transmitter provided in this embodiment introduces an impedance compensation array, which is arranged in parallel with the main array. The output impedance of the main array and the output impedance of the impedance compensation array are nonlinearly offset, so that the output impedance of the first node is maintained constant. The digitally controlled impedance compensation array generates an output impedance that is opposite to the change trend of the main array impedance with the control code, so that the output impedance of the radio frequency transmitter will not change with the change of the number of basic units turned on, and the output impedance remains constant with the control code, thereby fundamentally eliminating the factors that cause circuit nonlinearity.

[0042] In an optional embodiment of the present invention, see Figure 4 , Figure 4 is another schematic diagram of a radio frequency transmitter provided by an embodiment of the present invention, wherein the main array is a current source array, the impedance compensation array is an impedance compensation current source array, the basic unit 1 is a current source unit 1, and the basic unit 2 is a current source unit 2;

[0043] When the RF transmitter is working, X current source units 1 in the current source array are turned on, NX current source units 2 in the impedance compensation current source array are turned on, and the turned-on current source units 1 in the current source array work in response to the RF input signal and the baseband control code, and the turned-on current source units 2 in the impedance compensation current source array work in response to the fixed power supply signal V DC The complementary signal of the baseband control code operates to maintain the output impedance of the first node constant.

[0044] In an optional embodiment of the present invention, see Figure 5 , Figure 5 is a schematic diagram of a current source unit 1 in a current source array provided by an embodiment of the present invention, see Figure 6 , Figure 6 Schematic diagram of a current source unit 2 in an impedance compensation current source array provided by an embodiment of the present invention. The current source unit 1 includes a first transistor and a second transistor. The gate of the first transistor receives a radio frequency input signal. The bias voltage of the radio frequency input signal is V DC , the gate of the second transistor receives the baseband control code ACW, the drain of the first transistor is connected to the first signal line, the source of the first transistor is connected to the drain of the second transistor, and the source of the second transistor is grounded;

[0045] The current source unit 2 includes a third transistor and a fourth transistor, and the gate of the third transistor receives a fixed power signal V DC The gate of the fourth transistor receives the complementary signal of the baseband control code The drain of the third transistor is connected to the second signal line, the source of the third transistor is connected to the drain of the fourth transistor, and the source of the fourth transistor is grounded.

[0046] In an optional embodiment of the present invention, please continue to refer to Figure 5 and Figure 6 , also includes: a control circuit, the control circuit includes a radio frequency signal source and a baseband signal generating end; the output end of the radio frequency signal source is connected to the input end of the current source array, and is used to provide a radio frequency input signal to the current source array; the output end of the baseband signal generating end is connected to the input end of the current source array, and is used to provide a baseband signal to the current source array; the output end of the baseband signal generating end is connected to the input end of the impedance compensation current source array, and is used to provide a complementary signal of the baseband signal to the impedance compensation current source array.

[0047] In an optional embodiment of the present invention, see Figure 7 , Figure 7 is a schematic diagram of an equivalent circuit of a radio frequency transmitter provided by an embodiment of the present invention, wherein the output resistance of the current source array is R D / X, the output resistance of the impedance-compensated current source array is R D / (NX), the output capacitance of the current source array and the impedance compensation current source array at the first node is N(C on +C off ), the output impedance of the current source array and the impedance compensation current source array at the first node is:

[0048] Zout=R D / (X+NX)+1 / jω(Con+Coff)N;

[0049] Among them, R D is the on-resistance of the current source unit, C on is the parasitic resistance of the current source unit when it is turned on, C off is the parasitic resistance when the current source unit is turned off, j is the imaginary part of the impedance, and ω is the angular frequency.

[0050] For more details, please see Figure 7 In this embodiment, when the RF transmitter operates in the millimeter wave band, parasitic effects will occur due to the complex interconnection lines in the current source array and the impedance current source array. Due to the parasitic effect, parasitic capacitance and parasitic resistance will appear between adjacent current source units. The equivalent circuit is as follows: Figure 7 As shown; in the prior art, see Figure 8 , Figure 8 This is a schematic diagram of an equivalent circuit of a radio frequency transmitter in the prior art. As can be seen from the figure, when the impedance compensation current source array is not set, the output resistance is R D / X, output capacitance is XC on +(NX)C off , the output impedance is:

[0051] Zout'=R D / X+1 / jω(XCon+(NX)Coff);

[0052] By Z out ', it can be seen from the expression that when the impedance compensation current source array is not set, the output resistance and capacitance of the main array change with the change of the number of basic units turned on, thus causing the nonlinearity of the gain. When the impedance compensation current source array is connected in parallel, the output impedance remains constant and does not change with the change of the number of basic units turned on, thus fundamentally eliminating the factors that cause the circuit nonlinearity. See Fig. 9 , Fig. 9 3 is a comparative schematic diagram of the influence of the impedance compensation current source array provided in an embodiment of the present invention on the output impedance. It can be seen from the figure that after the impedance compensation current source array is set, the output impedance remains stable.

[0053] In an optional embodiment of the present invention, see Fig.10 , Fig.10It is a schematic diagram of a digital orthogonal transmitter architecture provided by an embodiment of the present invention, wherein an impedance compensation array is introduced into the digital orthogonal transmitter architecture, the main array is a power amplifier array, the impedance compensation array is an impedance compensation power amplifier array, the basic unit 1 is a power amplifier unit 1, and the basic unit 2 is a power amplifier unit 2;

[0054] The power amplifier array includes a first power amplifier array and a second power amplifier array, and the impedance compensation power amplifier array includes the first impedance compensation power amplifier array and the second impedance compensation power amplifier array; the first power amplifier array is arranged in parallel with the first impedance compensation power amplifier array, the output end of the power amplifier unit 1 in the first power amplifier array is connected in parallel through the first branch of the first signal line, and the output end of the power amplifier unit 2 in the first impedance compensation power amplifier array is connected to the second node through the first branch of the second signal line; the second power amplifier array is arranged in parallel with the second impedance compensation power amplifier array, the output end of the power amplifier unit 1 in the second power amplifier array is connected in parallel through the second branch of the first signal line, and the output end of the power amplifier unit 2 in the second impedance compensation power amplifier array is connected to the third node through the second branch of the second signal line;

[0055] When the RF transmitter is working, the X 1 Once the first power amplifier unit is turned on, the X in the second power amplifier array 2 As soon as the power amplifier unit is turned on, the NX in the first impedance compensation power amplifier array 1 The second power amplifier unit is turned on, and NX in the second impedance compensation power amplifier array 2 The power amplifier unit 2 is turned on, and the power amplifier unit 1 turned on in the first power amplifier array operates in response to the orthogonal local oscillator signal LOI and the IQ baseband signal BBIm, and the power amplifier unit 2 turned on in the first impedance compensation power amplifier array operates in response to the fixed power supply signal V DC The first power amplifier unit turned on in the second power amplifier array responds to the orthogonal local oscillator signal LOQ and the IQ baseband signal BBQm, and the second power amplifier unit turned on in the second impedance compensation power amplifier array responds to the fixed power supply signal V DC The complementary signal BBQmc of the IQ baseband signal BBQm operates to maintain the output impedance of the third node constant. I The output signal RF of the third node Q Synthesize and generate RF modulation signal out .

[0056] In an optional embodiment of the present invention, it also includes: a control circuit, the control circuit includes a radio frequency signal source and a baseband signal generating end; the output end of the radio frequency signal source is connected to the input end of the first power amplifier array, and is used to provide an orthogonal local oscillator signal LOI to the first power amplifier array, and the output end of the radio frequency signal source is connected to the input end of the second power amplifier array, and is used to provide an orthogonal local oscillator signal LOQ to the second power amplifier array; the output end of the baseband signal generating end is connected to the input end of the first power amplifier array, and is used to provide an IQ baseband signal BBIm to the first power amplifier array; the output end of the baseband signal generating end is connected to the input end of the second power amplifier array, and is used to provide an IQ baseband signal BBQm to the second power amplifier array; the output end of the baseband signal generating end is connected to the input end of the first impedance compensated power amplifier array, and is used to provide a complementary signal BBImc of the IQ baseband signal BBIm to the first impedance compensated power amplifier array; the output end of the baseband signal generating end is connected to the input end of the second impedance compensated power amplifier array, and is used to provide a complementary signal BBQmc of the IQ baseband signal BBQm to the second impedance compensated power amplifier array.

[0057] In this embodiment, the impedance compensation technology can be applied to a digital orthogonal transmitter to realize a broadband, high linearity, digital pre-distortion-free, and highly robust orthogonal transmitter.

[0058] In an optional embodiment of the present invention, see Fig.11 , Fig.11 1 is a schematic diagram of a digital polar transmitter architecture provided by an embodiment of the present invention, wherein an impedance compensation array is introduced into the digital polar transmitter architecture, the main array is a power amplifier array, the impedance compensation array is an impedance compensation power amplifier array, the basic unit 1 is a power amplifier unit 1, and the basic unit 2 is a power amplifier unit 2;

[0059] It also includes: a phase modulator, wherein the output end of the phase modulator is connected to the input end of the power amplifier array;

[0060] When the RF transmitter is working, the phase modulator receives the local oscillator signal LO and the baseband phase control code BBpm, and processes them to obtain the phase modulation signal PM; the X power amplifier units 1 in the power amplifier array are turned on, the NX power amplifier units 2 in the impedance compensation power amplifier array are turned on, and the turned-on power amplifier units 1 in the power amplifier array work in response to the phase modulation signal PM and the baseband phase control code BBam, and output the RF modulation signal RF out , the second power amplifier unit turned on in the impedance compensation power amplifier array responds to the fixed power supply signal V DC The complementary signal BBamc of the baseband phase control code BBam works to maintain the output impedance of the first node constant.

[0061] In an optional embodiment of the present invention, it also includes: a control circuit, the control circuit includes a radio frequency signal source and a baseband signal generating end; the output end of the radio frequency signal source is connected to the input end of the phase modulator, so as to provide the local oscillator signal LO to the phase modulator; the output end of the baseband signal generating end is connected to the input end of the phase modulator, so as to provide the baseband phase control code BBpm to the phase modulator, the output end of the baseband signal generating end is connected to the input end of the power amplifier array, so as to provide the baseband phase control code BBam to the power amplifier array, and the output end of the baseband signal generating end is connected to the input end of the impedance compensation power amplifier array, so as to provide the complementary signal BBamc of the baseband phase control code BBam to the impedance compensation power amplifier array.

[0062] In this embodiment, the impedance compensation technology can be applied to a digital polar transmitter to realize a broadband, high linearity, digital pre-distortion-free, and highly robust polar transmitter.

[0063] In an optional embodiment of the present invention, the effect of the radio frequency transmitter provided in the above embodiment is verified by simulation experiments, specifically:

[0064] See also Fig.12 , Fig.12 This is a schematic diagram of the effect of impedance compensation provided by an embodiment of the present invention on the output amplitude and output phase at different frequencies. Without impedance compensation, the output amplitude and output phase are obviously distorted. After impedance compensation, the output amplitude is linear and the output phase is flatter, which greatly improves the linearity of the transmitter. And at different frequencies, such as 22GHz, 24GHz, and 28GHz, the normalized output amplitude maintains extremely high linearity. Therefore, the impedance compensation technology proposed by the present invention is not sensitive to frequency and can achieve high linearity of the transmitter under broadband.

[0065] See also Fig.13 , Fig.13 This is a schematic diagram of the impedance change diagram provided by an embodiment of the present invention. When there is no impedance compensation, the output impedance will change with the change of the encoding; when there is impedance compensation, the output impedance can be maintained constant. Moreover, it can be seen that even with the change of frequency, the output impedance still does not change with the change of the encoding, which has high frequency stability and can be applied to broadband communications.

[0066] See also Fig.14 , Fig.14 It is a schematic diagram of the influence of temperature and process angle on output amplitude and phase provided by an embodiment of the present invention. It can be seen that under different temperatures and process angles, the impedance compensation technology has high linearity and high robustness.

[0067] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant is intended to cover non-exclusive inclusion, so that the article or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the article or device including the elements. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The orientation or position relationship indicated by "up", "down", "left", "right", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0068] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0069] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A radio frequency transmitter, characterized in that: include: at least one main array and at least one impedance compensation array; wherein, The main array and the impedance compensation array are arranged in parallel; the main array includes N basic units 1 arranged in parallel, and the impedance compensation array includes N basic units 2 arranged in parallel, the output ends of the plurality of basic units 1 are connected in parallel through a first signal line, and the output ends of the plurality of basic units 2 are connected in parallel through a second signal line, and the first signal line and the second signal line are connected to a first node; When the radio frequency transmitter is working, X basic units 1 in the main array are turned on, and NX basic units 2 in the impedance compensation array are turned on. The turned-on basic units 1 in the main array work in response to a baseband control code, and the turned-on basic units 2 in the impedance compensation array work in response to a complementary signal of the baseband control code. The impedance output by the main array and the impedance output by the impedance compensation array are nonlinearly offset, so that the output impedance of the first node is maintained constant.

2. The radio frequency transmitter according to claim 1, characterized in that: The main array is a current source array, the impedance compensation array is an impedance compensation current source array, the basic unit 1 is a current source unit 1, and the basic unit 2 is a current source unit 2; When the RF transmitter is working, X current source units 1 in the current source array are turned on, NX current source units 2 in the impedance compensation current source array are turned on, and the turned-on current source units 1 in the current source array work in response to the RF input signal and the baseband control code, and the turned-on current source units 2 in the impedance compensation current source array work in response to the fixed power supply signal V DC The complementary signal of the baseband control code operates to maintain the output impedance of the first node constant.

3. The radio frequency transmitter according to claim 2, characterized in that: The current source unit 1 includes a first transistor and a second transistor. The gate of the first transistor receives a radio frequency input signal. The bias voltage of the radio frequency input signal is V DC , the gate of the second transistor receives a baseband control code, the drain of the first transistor is connected to the first signal line, the source of the first transistor is connected to the drain of the second transistor, and the source of the second transistor is grounded; The second current source unit includes a third transistor and a fourth transistor, and the gate of the third transistor receives a fixed power signal V DC , the gate of the fourth transistor receives the complementary signal of the baseband control code, the drain of the third transistor is connected to the second signal line, the source of the third transistor is connected to the drain of the fourth transistor, and the source of the fourth transistor is grounded.

4. The radio frequency transmitter according to claim 3, characterized in that: Also includes: A control circuit, the control circuit comprising a radio frequency signal source and a baseband signal generating end; The output end of the radio frequency signal source is connected to the input end of the current source array, and is used to provide a radio frequency input signal to the current source array; The output end of the baseband signal generating end is connected to the input end of the current source array to provide a baseband signal to the current source array, and the output end of the baseband signal generating end is connected to the input end of the impedance compensation current source array to provide a complementary signal of the baseband signal to the impedance compensation current source array.

5. The radio frequency transmitter according to claim 2, characterized in that: The output resistance of the current source array is R D / X, the output resistance of the impedance compensation current source array is R D / (NX), the output capacitance of the current source array and the impedance compensation current source array at the first node is N(C on +C off ), the current source array and the impedance compensation current source array output impedance Z at the first node out for: Zout=R D / (X+NX)+1 / jω(Con+Coff)N! Among them, R D is the on-resistance of the current source unit, C on is the parasitic resistance of the current source unit when it is turned on, C off is the parasitic resistance when the current source unit is turned off, j is the imaginary part of the impedance, and ω is the angular frequency.

6. The radio frequency transmitter according to claim 1, characterized in that: The main array is a power amplifier array, the impedance compensation array is an impedance compensation power amplifier array, the basic unit 1 is a power amplifier unit 1, and the basic unit 2 is a power amplifier unit 2; The power amplifier array includes a first power amplifier array and a second power amplifier array, and the impedance-compensated power amplifier array includes a first impedance-compensated power amplifier array and a second impedance-compensated power amplifier array; the first power amplifier array is arranged in parallel with the first impedance-compensated power amplifier array, the output end of the power amplifier unit 1 in the first power amplifier array is connected in parallel through the first branch of the first signal line, and the output end of the power amplifier unit 2 in the first impedance-compensated power amplifier array is connected to the second node through the first branch of the second signal line; the second power amplifier array is arranged in parallel with the second impedance-compensated power amplifier array, the output end of the power amplifier unit 1 in the second power amplifier array is connected in parallel through the second branch of the first signal line, and the output end of the power amplifier unit 2 in the second impedance-compensated power amplifier array is connected to the third node through the second branch of the second signal line; When the RF transmitter is working, X1 power amplifier units 1 in the first power amplifier array are turned on, X2 power amplifier units 1 in the second power amplifier array are turned on, N-X1 power amplifier units 2 in the first impedance compensation power amplifier array are turned on, and N-X2 power amplifier units 2 in the second impedance compensation power amplifier array are turned on, and the turned-on power amplifier units 1 in the first power amplifier array work in response to the orthogonal local oscillator signal LOI and the IQ baseband signal BBIm, and the turned-on power amplifier units 2 in the first impedance compensation power amplifier array work in response to the fixed power supply signal V DC The first power amplifier unit turned on in the second power amplifier array operates in response to the orthogonal local oscillator signal LOQ and the IQ baseband signal BBQm, and the second power amplifier unit turned on in the second impedance compensation power amplifier array operates in response to the fixed power supply signal V DC The complementary signal BBQmc of the IQ baseband signal BBQm operates to maintain the output impedance of the third node constant.

7. The radio frequency transmitter according to claim 6, characterized in that: Also includes: A control circuit, the control circuit comprising a radio frequency signal source and a baseband signal generating end; The output end of the RF signal source is connected to the input end of the first power amplifier array, and is used to provide an orthogonal local oscillator signal LOI to the first power amplifier array. The output end of the RF signal source is connected to the input end of the second power amplifier array, and is used to provide an orthogonal local oscillator signal LOQ to the second power amplifier array. The output end of the baseband signal generating end is connected to the input end of the first power amplifier array, and is used to provide the IQ baseband signal BBIm to the first power amplifier array. The output end of the baseband signal generating end is connected to the input end of the second power amplifier array, and is used to provide the IQ baseband signal BBQm to the second power amplifier array. The output end of the baseband signal generating end is connected to the input end of the first impedance compensation power amplifier array, and is used to provide the complementary signal BBImc of the IQ baseband signal BBIm to the first impedance compensation power amplifier array. The output end of the baseband signal generating end is connected to the input end of the second impedance compensation power amplifier array, and is used to provide the complementary signal BBQmc of the IQ baseband signal BBQm to the second impedance compensation power amplifier array.

8. The radio frequency transmitter according to claim 1, characterized in that: The main array is a power amplifier array, the impedance compensation array is an impedance compensation power amplifier array, the basic unit 1 is a power amplifier unit 1, and the basic unit 2 is a power amplifier unit 2; It also includes: a phase modulator, wherein an output end of the phase modulator is connected to an input end of the power amplifier array; When the RF transmitter is working, the phase modulator receives the local oscillator signal LO and the baseband phase control code BBpm, and processes them to obtain a phase modulation signal PM; the X power amplifier units 1 in the power amplifier array are turned on, and the NX power amplifier units 2 in the impedance compensation power amplifier array are turned on, and the turned-on power amplifier units 1 in the power amplifier array respond to the phase modulation signal PM and the baseband phase control code BBam to work, and the turned-on power amplifier units 2 in the impedance compensation power amplifier array respond to the fixed power supply signal V DC The complementary signal BBamc of the baseband phase control code BBam works to maintain the output impedance of the first node constant.

9. The radio frequency transmitter according to claim 8, characterized in that: Also includes: A control circuit, the control circuit comprising a radio frequency signal source and a baseband signal generating end; The output end of the radio frequency signal source is connected to the input end of the phase modulator, and is used to provide a local oscillator signal LO to the phase modulator; The output end of the baseband signal generating end is connected to the input end of the phase modulator, and is used to provide the baseband phase control code BBpm to the phase modulator. The output end of the baseband signal generating end is connected to the input end of the power amplifier array, and is used to provide the baseband phase control code BBam to the power amplifier array. The output end of the baseband signal generating end is connected to the input end of the impedance compensation power amplifier array, and is used to provide the complementary signal BBamc of the baseband phase control code BBam to the impedance compensation power amplifier array.

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