High-linearity broadband receiver based on radio frequency passive gain

Abstract

The invention discloses a radio frequency passive gain-based high-linearity broadband receiver, which comprises a full-passive radio frequency front-end module and a second-order transimpedance amplification module, and is characterized in that the full-passive radio frequency front-end module is used for receiving a radio frequency input signal through an external antenna, carrying out out-of-band noise suppression on the radio frequency input signal to obtain a baseband signal, and transmitting the baseband signal to the second-order transimpedance amplification module through the second-order transimpedance amplification module; the second-order transimpedance amplification module is used for amplifying the baseband signal to obtain a baseband output signal, and the fully passive radio frequency front-end module is a multi-channel network based on a transformer. High linearity can be achieved through a full-passive framework, high-Q-value band-pass filtering response can be provided through a multi-channel network based on a transformer, out-of-band blocking signals can be effectively attenuated, in addition, the second-order trans-impedance amplification module with a plurality of conjugate poles is adopted for signal amplification, the requirement for wide signal bandwidth can be met, and the high-linearity band-pass filter can be obtained. The method can be widely applied to the technical field of wireless communication.

Description

Technical Field

[0001] This application relates to the field of wireless communication technologies, and in particular to a high-linearity broadband receiver based on radio frequency passive gain. Background Art

[0002] In order to support high-speed wireless communication in the sub-6 GHz band, especially the 5G New Radio (NR) standard, radio frequency receivers have been continuously developed to support wide signal bandwidths (e.g., 100 MHz in 5G-NR) and enhance the suppression of out-of-band blocking signals. In other words, in the spectrum-crowded sub-6 GHz band, the receiver needs to simultaneously meet the requirements of wide signal bandwidth and high suppression of adjacent out-of-band blocking signals while ensuring a low noise figure and high linearity. Existing technologies usually cannot meet both wide signal bandwidth and high out-of-band suppression simultaneously: 1) A gain-enhanced multi-channel structure is used as the low-noise amplifier of the receiver. Therefore, it is ensured that the front end of the receiver can provide gain to suppress the noise contribution of the subsequent circuits and provide a band-pass filter with a high Q value. However, its signal bandwidth is only 4 MHz, which seriously hinders its application in 5G New Radio communication.

[0003] 2) A multi-channel passive low-noise amplifier based on a transformer architecture is used. Although it provides relatively high linearity and a low noise figure (NF), this solution requires an off-chip broadband balun to generate differential inputs, increasing the cost. At the same time, a signal bandwidth of 20 MHz still cannot meet the requirements of 5G New Radio. Summary of the Invention

[0004] To solve the above technical problems, the purpose of the present invention is to provide a high-linearity broadband receiver based on radio frequency passive gain, which can simultaneously meet the requirements of wide signal bandwidth and high out-of-band suppression.

[0005] To achieve the above object, one aspect of the embodiments of this application proposes a high-linearity broadband receiver based on radio frequency passive gain, including a fully passive radio frequency front-end module and a second-order transimpedance amplification module. The input end of the fully passive radio frequency front-end module is used to connect to an external antenna. The output end of the fully passive radio frequency front-end module is connected to the input end of the second-order transimpedance amplification module. The fully passive radio frequency front-end module is used to receive a radio frequency input signal through the external antenna and perform out-of-band noise suppression on the radio frequency input signal to obtain a baseband signal. The second-order transimpedance amplification module is used to amplify the baseband signal to obtain a baseband output signal. Among them, the fully passive radio frequency front-end module is a multi-channel network based on a transformer.

[0006] In some embodiments, the all-passive radio frequency front-end module includes a low-noise amplification circuit and a multi-channel network. The multi-channel network includes a plurality of channel networks. The input end of the low-noise amplification circuit is used to receive the radio frequency input signal through the external antenna. The input ends of each of the channel networks are connected to the output end of the low-noise amplification circuit, and the output ends of each of the channel networks are connected to the input end of the second-order transimpedance amplification module. The low-noise amplification circuit is used to perform low-noise amplification on the radio frequency input signal to obtain a radio frequency output signal, and each of the channel networks is used to perform frequency conversion processing on the radio frequency output signal to obtain the baseband signal.

[0007] In some embodiments, the low-noise amplification circuit includes a step-up transformer and a first capacitor. The step-up transformer includes a first spiral coil and a second spiral coil. One end of the first spiral coil and the second spiral coil is connected to one end of the multi-channel network, and the other end of the first spiral coil and the second spiral coil is grounded. One end of the first capacitor is connected between the first spiral coil and the multi-channel network, and the other end of the first capacitor is connected between the second spiral coil and the multi-channel network. The step-up transformer is used to provide a passive voltage gain. The first spiral coil and the second spiral coil are used to perform inverse coupling on the radio frequency input signal to obtain the radio frequency output signal, and the first capacitor is used to cancel the center frequency shift.

[0008] In some embodiments, each of the channel networks includes a first switch and a second switch. One end of the first switch and the second switch is connected to the output end of the low-noise amplification circuit, and the other end of the first switch and the second switch is connected to the input end of the second-order transimpedance amplification module. The first switch and the second switch are used to perform down-conversion processing on the radio frequency output signal to obtain a first baseband signal.

[0009] In some embodiments, each of the channel networks further includes a second capacitor and a second capacitor. One end of the second capacitor is connected between the first switch and the second-order transimpedance amplification module, the other end of the second capacitor is connected to one end of the second capacitor, and the other end of the second capacitor is connected between the second switch and the second-order transimpedance amplification module. The low-noise amplification circuit is also connected between the second capacitor and the second capacitor. The second capacitor and the second capacitor are used to filter the first baseband signal, thereby enhancing out-of-band rejection.

[0010] In some embodiments, each of the channel networks further includes a third capacitor. One end of the third capacitor is connected between the first switch and the second-order transimpedance amplification module, and the other end of the third capacitor is connected between the second switch and the second-order transimpedance amplification module. The third capacitor is used to filter the first baseband signal, thereby enhancing out-of-band rejection.

[0011] In some embodiments, each of the channel networks further includes a third switch and a fourth switch. One end of the third switch is connected to one end of the first switch, and the other end of the third switch is connected to the input end of the second-order transimpedance amplification module. One end of the fourth switch is connected to one end of the second switch, and the other end of the fourth switch is connected to the input end of the second-order transimpedance amplification module. The third switch and the fourth switch are used to perform up-conversion processing on the filtered first baseband signal to obtain a second baseband signal.

[0012] In some embodiments, the first switch, the second switch, the third switch, and the fourth switch are all driven by a local oscillator signal with a 25% duty cycle. The first switch and the fourth switch in the same channel network are driven by the local oscillator signal of the first phase, and the second switch and the third switch in the same channel network are driven by the local oscillator signal of the second phase, and the phase difference between the first phase and the second phase is 180°.

[0013] In some embodiments, the second-order transimpedance amplification module includes a transimpedance amplifier, a first resistor, a second resistor, a fourth capacitor, and a fifth capacitor. The first resistor is connected between the first pin and the third pin of the transimpedance amplifier, the second resistor is connected between the second pin and the fourth pin of the transimpedance amplifier, the fourth capacitor is connected between the first pin and the second pin of the transimpedance amplifier, and the fifth capacitor is connected between the third pin and the fourth pin of the transimpedance amplifier. The transimpedance amplifier, the first resistor, the second resistor, the fourth capacitor, and the fifth capacitor are used to provide complex conjugate poles and amplify the baseband signal to obtain the baseband output signal.

[0014] In some embodiments, the bandwidth of the baseband output signal is greater than 50 MHZ.

[0015] The beneficial effects of the present invention are as follows: The high-linearity broadband receiver based on radio frequency passive gain of the present invention includes a fully passive radio frequency front-end module and a second-order transimpedance amplification module. The fully passive radio frequency front-end module is used to receive a radio frequency input signal through an external antenna, suppress out-of-band noise of the radio frequency input signal, and obtain a baseband signal. The second-order transimpedance amplification module is used to amplify the baseband signal to obtain a baseband output signal. Among them, the fully passive radio frequency front-end module is a multi-channel network based on a transformer. On the one hand, the present invention adopts a multi-channel network based on a transformer as the radio frequency front-end architecture. Through the fully passive architecture, the linearity can be effectively guaranteed, the requirement of high linearity can be achieved, and at the same time, passive voltage gain is provided to optimize the noise figure. And the multi-channel network based on a transformer can provide a band-pass filtering response with a high Q value, effectively attenuate out-of-band blocking signals, and achieve the requirement of high out-of-band suppression ratio. On the other hand, in order to improve the signal bandwidth and out-of-band suppression, a second-order transimpedance amplification module with complex conjugate poles is used to amplify the baseband signal, and the requirement of wide signal bandwidth can be achieved. Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following introduces the drawings required to be used in the embodiments of the present invention. It should be understood that the drawings introduced below only conveniently and clearly show some embodiments of the technical solutions in the present invention. For those skilled in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0017] Figure 1 It is a structural block diagram of a high-linearity broadband receiver based on radio frequency passive gain provided by an embodiment of the present invention; Figure 2 It is a circuit schematic diagram of a high-linearity broadband receiver based on radio frequency passive gain provided by an embodiment of the present invention; Figure 3 It is a schematic diagram of a local oscillator signal with a 25% duty cycle provided by an embodiment of the present invention; Figure 4 It is a gain response curve and input matching schematic diagram of the receiver at different frequencies provided by an embodiment of the present invention; Figure 5 It is a noise figure simulation schematic diagram of the receiver at different frequencies provided by an embodiment of the present invention; Figure 6 It is the receiver line IIP 3 and IIP 2 Linearity simulation schematic diagram; Figure 7 It is the receiver line B 1dB Linearity simulation schematic diagram.

[0018] Reference numeral: L1 , the first spiral coil; L 2 , the second spiral coil; C T , the first capacitor; C F1 , the second capacitor; C F2 , the third capacitor; C B1 , the fourth capacitor; C B2 , the fifth capacitor; C B3 , the sixth capacitor; SW NP1 , the first switch; SW NP2 , the second switch; SW B1 , the third switch; SW B1 , the fourth switch; R B1 , the first resistor; R B2 , the second resistor; G mB , the transimpedance amplifier. Detailed implementation manners

[0019] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all implementation manners consistent with the embodiments of the present application. They are only examples of devices and methods consistent with some aspects of the embodiments of the present application as detailed in the appended claims.

[0020] It can be understood that the terms "first", "second", etc. used in the present application may be used herein to describe various concepts, but unless otherwise specified, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the words "if", "when" used herein may be interpreted as "when...", "while...", or "in response to determining".

[0021] The terms "at least one", "a plurality of", "each", "any one", etc. used in the present application, at least one includes one, two or more, a plurality includes two or more, each refers to each of the corresponding plurality, and any one refers to any one of the plurality.

[0022] Before elaborating on the embodiments of the present application in detail, some nouns and terms involved in the embodiments of the present application will be described first. The nouns and terms involved in the embodiments of the present application are applicable to the following explanations.

[0023] LNA (Low-Noise Amplifier) Low-Noise Amplifier.

[0024] LO (Local Oscillator) Local Oscillator.

[0025] BB (Baseband) Baseband.

[0026] TIA (Trans-Impedance Amplifier) Trans-Impedance Amplifier.

[0027] NF (Noise Figure) Noise Figure.

[0028] IIP 3 (3rd-Order Input-Referred Interception Point) Third-Order Input-Referred Interception Point.

[0029] IIP 2 (2nd-Order Input-Referred Interception Point) Second-Order Input-Referred Interception Point.

[0030] NR(New Radio) New Radio.

[0031] OB(Out-of-Band) Out-of-Band.

[0032] B 1dB (Blocker-Caused-1dB Gain Compression Point) Blocker-Caused-1dB Gain Compression Point.

[0033] To support high-speed wireless communication in the sub-6GHz band, especially the 5G New Radio (NR) standard, RF receivers are continuously evolving to support wide signal bandwidths (e.g., 100MHz in 5G-NR) and enhance the suppression of out-of-band blocker signals. In other words, in the spectrum-crowded sub-6GHz band, the receiver must simultaneously meet the requirements of wide signal bandwidth and high suppression of adjacent out-of-band blocker signals while ensuring low noise figure and high linearity. Existing technologies usually cannot meet both wide signal bandwidth and high out-of-band suppression simultaneously: 1) Using a gain-enhanced multi-channel structure as the low-noise amplifier of the receiver, thus ensuring that the front end of the receiver can provide gain to suppress the noise contribution of the subsequent circuits and providing a high-Q bandpass filter at the same time. However, its signal bandwidth is only 4MHz, seriously hindering its application in 5G New Radio communication; 2) The multi-channel passive low-noise amplifier based on the transformer architecture is adopted. Although it provides relatively high linearity and a low noise figure (NF), this solution requires an off-chip broadband balun to generate differential inputs, increasing the cost. Meanwhile, the signal bandwidth of 20 MHz still cannot meet the requirements of the 5G new air interface.

[0034] Therefore, the embodiment of the present invention proposes a high-linearity broadband receiver based on radio frequency (RF) passive gain, which includes a fully passive RF front-end module and a second-order transimpedance amplification module. The fully passive RF front-end module is used to receive an RF input signal through an external antenna and suppress out-of-band noise of the RF input signal to obtain a baseband signal. The second-order transimpedance amplification module is used to amplify the baseband signal to obtain a baseband output signal. Among them, the fully passive RF front-end module is a multi-channel network based on a transformer. On the one hand, the multi-channel network based on a transformer is adopted as the RF front-end architecture. Through the fully passive architecture, the linearity can be effectively guaranteed to meet the requirement of high linearity, and at the same time, passive voltage gain is provided to optimize the noise figure. Moreover, the multi-channel network based on a transformer can provide a band-pass filtering response with a high Q value to effectively attenuate out-of-band blocking signals and meet the requirement of high out-of-band suppression. On the other hand, in order to improve the signal bandwidth and out-of-band suppression, a second-order transimpedance amplification module with complex conjugate poles is used to amplify the baseband signal, which can meet the requirement of a wide signal bandwidth.

[0035] Refer to Figure 1 , Figure 1 FIG. [X] is a structural block diagram of the high-linearity broadband receiver based on RF passive gain provided by the embodiment of the present invention. The embodiment of the present invention proposes a high-linearity broadband receiver based on RF passive gain, which includes a fully passive RF front-end module and a second-order transimpedance amplification module. The input end of the fully passive RF front-end module is used to connect to an external antenna. The output end of the fully passive RF front-end module is connected to the input end of the second-order transimpedance amplification module. The fully passive RF front-end module is used to receive an RF input signal through an external antenna and suppress out-of-band noise of the RF input signal to obtain a baseband signal. The second-order transimpedance amplification module is used to amplify the baseband signal to obtain a baseband output signal. Among them, the fully passive RF front-end module is a multi-channel network based on a transformer.

[0036] It should be noted that the embodiment of the present invention adopts a multi-channel network based on a transformer as the RF front-end architecture. Through the fully passive architecture, the linearity is effectively guaranteed, and at the same time, passive voltage gain is provided to optimize the noise figure (NF). Moreover, the multi-channel network based on a transformer can provide a band-pass filtering response with a high Q value to effectively attenuate out-of-band blocking signals. In addition, in order to improve the signal bandwidth and out-of-band suppression, the embodiment of the present invention uses a second-order transimpedance amplifier (TIA) with complex conjugate poles to amplify the baseband signal to achieve the goal of a wide signal bandwidth.

[0037] Among them, a wide signal bandwidth means that the signal can contain more frequency components, thereby carrying more information. Out-of-band rejection refers to the ability to suppress or attenuate signals outside the normal frequency range (or called out-of-band). A high out-of-band rejection ratio can ensure that the signal is not interfered by other frequency signals during transmission, thereby improving the reliability and stability of communication.

[0038] Referring to Figure 1 , further as an optional implementation manner, the all-passive RF front-end module includes a low-noise amplifier circuit and a multi-channel network. The multi-channel network includes multiple channel networks. The input end of the low-noise amplifier circuit is used to receive a radio frequency input signal through an external antenna. The input ends of each channel network are connected to the output end of the low-noise amplifier circuit, and the output ends of each channel network are connected to the input end of the second-order transimpedance amplifier module. The low-noise amplifier circuit is used to perform low-noise amplification on the radio frequency input signal to obtain a radio frequency output signal, and each channel network is used to perform frequency conversion processing on the radio frequency output signal to obtain a baseband signal.

[0039] Specifically, the receiver receives a radio frequency input signal through an external antenna. The received radio frequency input signal is mixed with various noises and interferences, and then the radio frequency input signal is injected into the all-passive RF front-end module. The all-passive RF front-end module consists of a low-noise amplifier circuit and a multi-channel network. The radio frequency input signal is amplified by the low-noise amplifier circuit to initially attenuate out-of-band blocking signals and obtain a radio frequency output signal. The amplified radio frequency output signal is subjected to frequency conversion processing through the multi-channel network to convert the radio frequency signal from the high frequency band to the low frequency band (i.e., the baseband), and at the same time, out-of-band noise suppression is achieved to obtain a baseband signal.

[0040] Referring to Figure 2 , Figure 2 is the circuit schematic diagram of the high-linearity broadband receiver based on RF passive gain provided by the embodiment of the present invention. Further as an optional implementation manner, the low-noise amplifier circuit includes a step-up transformer and a first capacitor C T , the step-up transformer includes a first spiral coil L 1 and a second spiral coil L 2 , one end of the first spiral coil L 1 and the second spiral coil L 2 are both connected to one end of the multi-channel network. The other ends of the first spiral coil L 1 and the second spiral coil L 2 are both grounded. One end of the first capacitor C T is connected between the first spiral coil L 1 and the multi-channel network, and the other end of the first capacitor C T is connected between the second spiral coil L 2 and the multi-channel network. The step-up transformer is used to provide passive voltage gain. The first spiral coil L1 and the second spiral coil L 2 is used to perform inverse coupling on the RF input signal to obtain an RF output signal. The first capacitor C T is used to cancel the center frequency shift.

[0041] Specifically, in order to improve the linearity and noise figure (NF), the embodiment of the present invention uses a step-up transformer to provide passive voltage gain, minimizes the non-linear effect through the step-up transformer, and thus avoids the linearity problem caused by active devices while maintaining low noise. The two spiral coils (the first spiral coil L 1 and the second spiral coil L 2 ) in the step-up transformer are vertically coupled. When the RF input signal V i，RF passes through the first spiral coil L 1 , it will induce a current with the same magnitude but opposite phase in the second spiral coil L 2 , that is, the RF output signal V o，RF . Because the multi-channel network presents a high impedance at f LO , and the out-of-band blocking signal is inversely coupled by the step-up transformer and transmitted to the RF output signal V o，RF through the multi-channel network, resulting in partial cancellation of the blocking signal. Therefore, the transformer-based multi-channel low-noise amplifier (LNA) provides high-Q band-pass filtering at both the RF input signal V i，RF and the RF output signal V o，RF . In addition, the first capacitor C T around the step-up transformer is used to cancel the center frequency shift.

[0042] Furthermore, the transformer adopted in the embodiment of the present invention also has an inductance characteristic, which can effectively cancel the parasitic capacitance at the RF input end, thereby broadening the RF coverage range.

[0043] Referring to Figure 2 , as a further optional implementation manner, each channel network includes a first switch SW NP1 and a second switch SW NP2 . One ends of the first switch SW NP1 and the second switch SW NP2 are both connected to the output end of the low-noise amplification circuit. The other ends of the first switch SW NP1 and the second switch SW NP2 are both connected to the input end of the second-order transimpedance amplification module. The first switch SW NP1 and the second switch SW NP2 are used to perform down-conversion processing on the RF output signal to obtain a first baseband signal.

[0044] Specifically, the RF output signal V o，RFAfter passing through the first switch SW NP1 and the second switch SW NP2 perform down-conversion processing, and the first switch SW NP1 and the second switch SW NP2 also operate as a demodulator, using the local oscillator (LO) signal as a reference signal, and by controlling the on / off state of the switch, adjust the frequency and phase of the received radio frequency output signal V o，RF to restore it to a baseband signal (i.e., the first baseband signal).

[0045] Among them, down-conversion (Down Conversion) refers to converting an input signal with a certain frequency into an output signal with a lower frequency.

[0046] Refer to Figure 2 , as a further optional implementation manner, each channel network also includes a second capacitor C F1 and a third capacitor C F2 , one end of the second capacitor C F1 is connected between the first switch SW NP1 and the second-order transimpedance amplification module, the other end of the second capacitor C F1 is connected to one end of the third capacitor C F2 , the other end of the third capacitor C F2 is connected between the second switch SW NP2 and the second-order transimpedance amplification module, and a low-noise amplification circuit is also connected between the second capacitor C F1 and the third capacitor C F2 , and the second capacitor C F1 and the third capacitor C F2 are used to filter the first baseband signal, thereby enhancing out-of-band rejection.

[0047] Refer to Figure 2 , as a further optional implementation manner, each channel network also includes a fourth capacitor C B1 , one end of the fourth capacitor C B1 is connected between the first switch SW NP1 and the second-order transimpedance amplification module, and the other end of the fourth capacitor C B1 is connected between the second switch SW NP2 and the second-order transimpedance amplification module, and the fourth capacitor C B1 is used to filter the first baseband signal, thereby enhancing out-of-band rejection.

[0048] Specifically, the first baseband signal obtained by down-conversion processing passes through the second capacitor C NP1 connected in parallel between the first switch SW NP2 and the second switch SW F1 , the third capacitor C F2and a fourth capacitor C B1 Perform filtering to remove out-of-band noise and interference in the baseband signal and enhance the out-of-band rejection of the receiver.

[0049] Refer to Figure 2 , and further as an optional implementation manner, each channel network further includes a third switch SW B1 and a fourth switch SW B1 . One end of the third switch SW B1 is connected to one end of the first switch SW NP1 . The other end of the third switch SW B1 is connected to the input end of the second-order transimpedance amplification module. One end of the fourth switch SW B1 is connected to one end of the second switch SW NP2 . The other end of the fourth switch SW B1 is connected to the input end of the second-order transimpedance amplification module. The third switch SW B1 and the fourth switch SW B1 are used to perform up-conversion processing on the filtered first baseband signal to obtain a second baseband signal.

[0050] Further as an optional implementation manner, the first switch SW NP1 , the second switch SW NP2 , the third switch SW B1 and the fourth switch SW B1 are all driven by a local oscillator signal with a 25% duty cycle. The first switch SW NP1 and the fourth switch SW B1 in the same channel network are driven by a local oscillator signal of the first phase. The second switch SW NP2 and the third switch SW B1 in the same channel network are driven by a local oscillator signal of the second phase, and the phase difference between the first phase and the second phase is 180°.

[0051] Specifically, the filtered first baseband signal passes through the third switch SW B1 and the fourth switch SW B1 to perform up-conversion processing according to a local oscillator signal with a 25% duty cycle to obtain a second baseband signal, and then output the second baseband signal to the second-order transimpedance amplification module for amplification.

[0052] It should be noted that, as shown in Figure 3 , the schematic diagram of the local oscillator signal with a 25% duty cycle is shown. The first switch SW NP1 , the fourth switch SW B1 and the second switch SW NP2 , the third switch SW B1Driven by two non - overlapping local oscillator (LO) signals with a 25% duty cycle, and the phases of these two LO signals differ by 180°. Meanwhile, the center frequency of the signal is defined by the local oscillator frequency f LO Define.

[0053] Among them, up - conversion refers to the process of converting an input signal with a certain frequency into an output signal with a higher frequency.

[0054] Refer to Figure 2 , further as an optional implementation manner, the second - order trans - impedance amplification module includes a trans - impedance amplifier G mB , a first resistor R B1 , a second resistor R B2 , a fifth capacitor C B2 and a sixth capacitor C B3 . The first resistor R B1 is connected between the first pin and the third pin of the trans - impedance amplifier G mB . The second resistor R B2 is connected between the second pin and the fourth pin of the trans - impedance amplifier G mB . The fifth capacitor C B2 is connected between the first pin and the second pin of the trans - impedance amplifier G mB . The sixth capacitor C B3 is connected between the third pin and the fourth pin of the trans - impedance amplifier G mB . The trans - impedance amplifier G mB , the first resistor R B1 , the second resistor R B2 , the fifth capacitor C B2 and the sixth capacitor C B3 are used to provide complex conjugate poles and amplify the base - band signal to obtain a base - band output signal.

[0055] Further as an optional implementation manner, the bandwidth of the base - band output signal is greater than 50 MHZ.

[0056] Specifically, there are multiple second - order trans - impedance amplification modules in the embodiments of the present invention, which are respectively connected to the output ends of each channel network. To expand the signal bandwidth, the embodiments of the present invention adopt a second - order BB (base - band) TIA (trans - impedance amplifier G mB ), which includes an inverter - based trans - impedance amplifier G mB , feedback resistors (the first resistor R B1 and the second resistor R B2 ) and two parallel capacitors (the fifth capacitor C B2 and the sixth capacitor C B3 ) to provide complex conjugate poles and amplify the base - band signal to increase the amplitude and driving ability of the base - band signal. Finally, the amplified base - band output signal (VB3，I± and V B3，Q± is output at the baseband output end. The baseband output signal obtained by the receiver according to the embodiment of the present invention has a bandwidth greater than 50 MHz, which can meet the requirements of the 5G new air interface.

[0057] The structure and working principle of the high-linearity broadband receiver based on radio frequency passive gain according to the embodiment of the present invention are described above. It can be recognized that compared with the traditional receiver, on the one hand, the present invention adopts a multi-channel network based on a transformer as the radio frequency front-end architecture. Through a fully passive architecture, the linearity can be effectively guaranteed, the requirement of high linearity can be achieved, and at the same time, passive voltage gain is provided to optimize the noise figure. And the multi-channel network based on the transformer can provide a band-pass filtering response with a high Q value, effectively attenuate out-of-band blocking signals, and achieve the requirement of high out-of-band rejection ratio. On the other hand, in order to improve the signal bandwidth and out-of-band rejection, a second-order transimpedance amplification module with complex conjugate poles is used to amplify the baseband signal, which can achieve the requirement of a wide signal bandwidth.

[0058] To further verify the reliability of the embodiment of the present invention, the effects of the embodiment of the present invention will be further described below in combination with the simulation experiment results.

[0059] The simulation results show that as Figure 4 is the gain response curve and input matching schematic diagram of the receiver at different frequencies. It can be seen from Figure 4 that the simulation gain response and input matching S of the receiver in the radio frequency range of 2 to 3 GHz 11 where the passband gain is 12.2 to 13.5 dB, the signal bandwidth is 110 MHz, and the input matching S 11 is -10 dB. And at the frequency offset of twice the signal bandwidth, the out-of-band rejection reaches 34 dB. As Figure 5 shows the noise figure simulation schematic diagram of the receiver at different frequencies. It can be seen from Figure 5 that for the radio frequency range of 2 to 3 GHz, the noise figure simulation of the receiver is 3.4 to 3.8 dB. As Figure 6 shows the linearity simulation schematic diagram of the receiver line IIP 3 and IIP 2 It can be seen from Figure 6 that the simulation performance OB-IIP 3 and OB-IIP 2 of the receiver are 13 dBm and 57 dBm respectively at the frequency offset of five times the signal bandwidth. As Figure 7 shows the linearity simulation schematic diagram of the receiver line B 1dB It can be seen from Figure 7 that at the frequency offset of five times the signal bandwidth, the simulation B 1dB of the receiver is -4.5 dBm.

[0060] In the foregoing description of this specification, the descriptions referring to the terms "one embodiment / example", "another embodiment / example" or "certain embodiments / examples", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0061] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the claims and their equivalents.

[0062] The above is a specific description of the preferred embodiments of the present invention, but the present invention is not limited to the embodiments. Those skilled in the art can also make various equivalent deformations or substitutions without departing from the spirit of the present invention, and these equivalent deformations or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A high linearity broadband receiver based on RF passive gain, characterized in that: It includes a fully passive RF front-end module and a second-order transimpedance amplifier module, wherein the input end of the fully passive RF front-end module is used to connect to an external antenna, and the output end of the fully passive RF front-end module is connected to the input end of the second-order transimpedance amplifier module, and the fully passive RF front-end module is used to receive an RF input signal through the external antenna and perform out-of-band noise suppression on the RF input signal to obtain a baseband signal, and the second-order transimpedance amplifier module is used to amplify the baseband signal to obtain a baseband output signal, wherein the fully passive RF front-end module is a transformer-based multi-channel network.

2. A high linearity broadband receiver based on RF passive gain according to claim 1, characterized in that: The fully passive RF front-end module includes a low-noise amplifier circuit and a multi-channel network, the multi-channel network includes multiple channel networks, the input end of the low-noise amplifier circuit is used to receive the RF input signal through the external antenna, the input end of each channel network is connected to the output end of the low-noise amplifier circuit, the output end of each channel network is connected to the input end of the second-order transimpedance amplifier module, the low-noise amplifier circuit is used to perform low-noise amplification on the RF input signal to obtain a RF output signal, and each channel network is used to perform frequency conversion processing on the RF output signal to obtain the baseband signal.

3. A high linearity broadband receiver based on RF passive gain according to claim 2, characterized in that: The low-noise amplifier circuit includes a step-up transformer and a first capacitor. The step-up transformer includes a first spiral coil and a second spiral coil. One end of the first spiral coil and the second spiral coil are both connected to one end of the multi-channel network, and the other ends of the first spiral coil and the second spiral coil are both grounded. One end of the first capacitor is connected between the first spiral coil and the multi-channel network, and the other end of the first capacitor is connected between the second spiral coil and the multi-channel network. The step-up transformer is used to provide passive voltage gain. The first spiral coil and the second spiral coil are used to perform anti-phase coupling on the RF input signal to obtain the RF output signal. The first capacitor is used to offset the center frequency shift.

4. A high linearity broadband receiver based on RF passive gain according to claim 2, characterized in that: Each of the channel networks includes a first switch and a second switch, one end of the first switch and the second switch are connected to the output end of the low-noise amplifier circuit, and the other end of the first switch and the second switch are connected to the input end of the second-order transimpedance amplifier module, and the first switch and the second switch are used to down-convert the RF output signal to obtain a first baseband signal.

5. The high linearity broadband receiver based on radio frequency passive gain according to claim 4, characterized in that: Each of the channel networks also includes a second capacitor and a third capacitor, one end of the second capacitor is connected between the first switch and the second-order transimpedance amplifier module, the other end of the second capacitor is connected to one end of the third capacitor, the other end of the third capacitor is connected between the second switch and the second-order transimpedance amplifier module, the low-noise amplifier circuit is also connected between the second capacitor and the third capacitor, and the second capacitor and the third capacitor are used to filter the first baseband signal to enhance out-of-band suppression.

6. A high linearity broadband receiver based on RF passive gain according to claim 4, characterized in that: Each of the channel networks also includes a fourth capacitor, one end of the fourth capacitor is connected between the first switch and the second-order transimpedance amplifier module, and the other end of the fourth capacitor is connected between the second switch and the second-order transimpedance amplifier module, and the fourth capacitor is used to filter the first baseband signal to enhance out-of-band suppression.

7. The high linearity broadband receiver based on RF passive gain according to claim 4, characterized in that: Each of the channel networks also includes a third switch and a fourth switch, one end of the third switch is connected to one end of the first switch, and the other end of the third switch is connected to the input end of the second-order transimpedance amplifier module, one end of the fourth switch is connected to one end of the second switch, and the other end of the fourth switch is connected to the input end of the second-order transimpedance amplifier module, and the third switch and the fourth switch are used to up-convert the filtered first baseband signal to obtain a second baseband signal.

8. The high linearity broadband receiver based on radio frequency passive gain according to claim 7, characterized in that: The first switch, the second switch, the third switch and the fourth switch are all driven by a local oscillator signal with a duty cycle of 25%, the first switch and the fourth switch in the same channel network are driven by the local oscillator signal of a first phase, the second switch and the third switch in the same channel network are driven by the local oscillator signal of a second phase, and the phase difference between the first phase and the second phase is 180°.

9. The high linearity broadband receiver based on RF passive gain according to claim 1, characterized in that: The second-order transimpedance amplifier module includes a transimpedance amplifier, a first resistor, a second resistor, a fifth capacitor and a sixth capacitor, wherein the first resistor is connected between the first pin and the third pin of the transimpedance amplifier, the second resistor is connected between the second pin and the fourth pin of the transimpedance amplifier, the fifth capacitor is connected between the first pin and the second pin of the transimpedance amplifier, and the sixth capacitor is connected between the third pin and the fourth pin of the transimpedance amplifier. The transimpedance amplifier, the first resistor, the second resistor, the fifth capacitor and the sixth capacitor are used to provide complex conjugate poles and amplify the baseband signal to obtain the baseband output signal.

10. A high linearity broadband receiver based on radio frequency passive gain according to any one of claims 1 to 9, characterized in that: The bandwidth of the baseband output signal is greater than 50 MHz.

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