RF Receiver Front-End Architecture Based on High-Order N-Channel Low-Pass Filter

Abstract

The present application discloses a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter, which includes a fourth-order gain-enhanced N-channel low-noise amplifier component, two sets of switching mixer circuits, and a high-order N-channel low-pass filter. The low-noise amplifier is used to amplify radio frequency signals; a tunable fourth-order LC circuit is connected in parallel with the low-noise amplifier; one set of the switching mixer circuits is used to mix the amplified radio frequency signal and the local oscillator signal generated by the switching mixer circuit to obtain a mixed signal; the other set is used to determine the bandwidth of the receiving front-end architecture; the high-order N-channel low-pass filter is generated based on an N-channel notch filter and a negative resistor and is used to suppress out-of-band blocking interference signals in the mixed signal. According to the technical solution of the present application, the high-order N-channel low-pass filter replaces the transimpedance amplifier to achieve the goals of high performance and low cost of the radio frequency receiving front-end architecture.

Description

Technical Field

[0001] The present application relates to the technical field of radio frequency receivers, and in particular to a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter. Background Art

[0002] The launch of the 5G-NR (5G New Radio) mobile communication standard has brought new challenges to the design of Sub-6GHz RF receivers. Existing mobile device terminals are based on SAW (surface acoustic wave) filters to support FDD (frequency division duplex) operation. However, according to the 3GPP (the 3rd Generation Partnership Project) standard, there are many defined 5G frequency bands, and adding more SAW filters cannot be well expanded, resulting in increased costs. At the same time, the insertion loss of the SAW filter will also affect the working performance of the RF front-end circuit. How to replace the multi-band parallel receiving front-end architecture used in traditional multi-mode and multi-standard receivers to achieve the goal of high performance and low cost of the RF receiver front end is a technical problem that needs to be solved urgently. Summary of the invention

[0003] An embodiment of the present application provides a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter, which uses a high-order N-channel low-pass filter to replace a transimpedance amplifier to achieve the goal of high performance and low cost of the radio frequency receiving front-end architecture.

[0004] In a first aspect, an embodiment of the present application provides a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter, including:

[0005] A fourth-order gain-enhanced N-channel low-noise amplifier component, the low-noise amplifier component comprising a low-noise amplifier and a tunable fourth-order LC circuit connected in parallel with the low-noise amplifier, the low-noise amplifier being used to amplify a received radio frequency signal;

[0006] Two groups of switch mixer circuits, one group of the switch mixer circuits is used to mix the amplified radio frequency signal with the local oscillator signal generated by the switch mixer circuit to obtain a mixed signal; the other group is used to determine the bandwidth of the receiving front-end architecture according to the local oscillator signal;

[0007] A high-order N-channel low-pass filter is generated based on an N-channel notch filter and a negative resistor, and is used to suppress out-of-band blocking interference signals in the mixed signal.

[0008] The radio frequency (RF) receiving front-end architecture based on a high-order N-channel low-pass filter provided by an embodiment of the present application has at least the following beneficial effects: The RF receiving front-end architecture includes a fourth-order gain-enhanced N-channel low-noise amplifier component, two sets of switch mixer circuits, and a high-order N-channel low-pass filter. The low-noise amplifier component includes a low-noise amplifier and a tunable fourth-order LC circuit connected in parallel with the low-noise amplifier. The low-noise amplifier is used to amplify the received RF signal. One set of the switch mixer circuits is used to mix the amplified RF signal and the local oscillator signal generated by the switch mixer circuit to obtain a mixed signal. The other set is used to determine the bandwidth of the receiving front-end architecture according to the local oscillator signal. The high-order N-channel low-pass filter is generated based on an N-channel notch filter and a negative resistor, and is used to suppress out-of-band blocking interference signals in the mixed signal. According to the technical solution of the present application, due to the frequency tunability of the fourth-order gain-enhanced N-channel low-noise amplifier component, the purpose of miniaturizing the RF receiving front-end is achieved. Moreover, the high-order N-channel low-pass filter replaces the transimpedance amplifier to achieve attenuation and suppression of out-of-band blocking interference signals and maintain good in-band linearity. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 is a schematic structural diagram of an RF receiving front-end architecture based on a high-order N-channel low-pass filter provided by an embodiment of the present application;

[0010] Figure 2 is a schematic structural diagram of the LNA in the RF receiving front-end architecture based on a high-order N-channel low-pass filter provided by an embodiment of the present application;

[0011] Figure 3 is a schematic structural diagram of the LC circuit in the RF receiving front-end architecture based on a high-order N-channel low-pass filter provided by an embodiment of the present application;

[0012] Figure 4 is a schematic structural diagram of the filter in the RF receiving front-end architecture based on a high-order N-channel low-pass filter in the related art provided by an embodiment of the present application;

[0013] Figure 5 is a schematic structural diagram of the filter in the RF receiving front-end architecture based on a high-order N-channel low-pass filter provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] 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 and are not used to limit the present application.

[0015] It should be noted that the terms "first", "second", etc. in this application are used to distinguish similar objects, and do not necessarily describe a specific order or sequence.

[0016] It should be noted that in each specific embodiment of this application, when it comes to performing relevant processing based on the attribute information or set of attribute information of a target object (such as a user, etc.) and data related to the characteristics of the target object, the permission or consent of the target object will be obtained first. Moreover, the collection, use, and processing of this data will comply with the relevant laws, regulations, and standards of relevant countries and regions. In addition, when an embodiment of this application needs to obtain the attribute information of a target object, it will obtain the separate permission or separate consent of the target object through methods such as pop-up windows or jumping to a confirmation page. After clearly obtaining the separate permission or separate consent of the target object, the relevant data of the target object necessary for the normal operation of the embodiment of this application will be obtained.

[0017] The introduction of the 5G-NR (5G New Radio) mobile communication standard has brought new challenges to the design of Sub-6GHz radio frequency receivers (RX). First of all, in order to support higher communication rates, the maximum RF-BW (Radio-Frequency BandWidth) of 5G has increased to 100MHz, and improving the bandwidth of the radio frequency front-end circuit has become the primary goal. Secondly, existing mobile device terminals are based on SAW (Surface Acoustic Wave) filters to support FDD (Frequency Division Duplex) operation. To achieve FDD operation, the radio frequency front-end circuit must provide sufficient isolation at both the receiving and transmitting frequencies. That is, at the transmitting frequency, the radio frequency front-end circuit needs to prevent the high-power transmitted signal from causing gain compression in the RX; at the receiving frequency, the radio frequency front-end circuit needs to prevent the transmitter (TX) noise from reducing the RX sensitivity.

[0018] However, according to the 3GPP (the 3rd Generation Partnership Project) standard, there are numerous 5G frequency bands defined, and adding more SAW filters cannot be well extended, resulting in increased costs. At the same time, the insertion loss of the SAW filter will also affect the working performance of the radio frequency front-end circuit.

[0019] Therefore, according to the Software Defined Radio (SDR) proposed by researchers, a programmable tunable radio frequency front-end, especially a front-end circuit with high-Q filtering characteristics, is crucial for supporting FDD operation in 5G-NR applications. It is expected to replace off-chip SAW filters and achieve a SAW-less receiver without off-chip SAW filters.

[0020] This application focuses on the radio frequency front-end circuit for 5G-NR applications, and particularly studies the tunable anti-blocking SAW-less radio frequency front-end receiving front-end architecture. Based on theoretical analysis, it completes the application-oriented radio frequency front-end circuit design, and then replaces the multi-band parallel receiving front-end architecture used in traditional multi-mode multi-standard receivers to achieve the goals of high performance and low cost for the radio frequency receiver front-end.

[0021] This application provides a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter, including a fourth-order gain-enhanced N-channel low-noise amplifier component, two sets of switch mixer circuits, and a high-order N-channel low-pass filter. The low-noise amplifier component includes a low-noise amplifier and a tunable fourth-order LC circuit connected in parallel with the low-noise amplifier. The low-noise amplifier is used to amplify the received radio frequency signal. One set of switch mixer circuits is used to mix the amplified radio frequency signal with the local oscillator signal generated by the switch mixer circuit to obtain a mixed signal. The other set is used to determine the bandwidth of the receiving front-end architecture according to the local oscillator signal. The high-order N-channel low-pass filter is generated based on an N-channel notch filter and a negative resistor, and is used to suppress out-of-band blocking interference signals in the mixed signal. According to the technical solution of this application, due to the frequency tunability of the fourth-order gain-enhanced N-channel low-noise amplifier component, the goal of miniaturization of the radio frequency receiving front-end is achieved. Moreover, the high-order N-channel low-pass filter replaces the transimpedance amplifier to achieve attenuation and suppression of out-of-band blocking interference signals and maintain good in-band linearity.

[0022] The following further elaborates on the embodiments of this application with reference to the accompanying drawings.

[0023] As Figure 1 shown, Figure 1It is a schematic structural diagram of a radio frequency (RF) receiving front-end architecture based on a high-order N-channel low-pass filter provided by an embodiment of the present application. The RF receiving front-end architecture includes a fourth-order gain-enhanced N-channel low-noise amplifier component, two sets of switching mixer circuits, and a high-order N-channel low-pass filter. The low-noise amplifier component includes a low-noise amplifier and a tunable fourth-order LC circuit connected in parallel with the low-noise amplifier. The low-noise amplifier is used to amplify the received RF signal; the tunable fourth-order LC circuit is connected in parallel with the low-noise amplifier; one set of the switching mixer circuits is used to mix the amplified RF signal and the local oscillator signal generated by the switching mixer circuit to obtain a mixed signal; the other set is used to determine the bandwidth of the receiving front-end architecture according to the local oscillator signal; the high-order N-channel low-pass filter is generated based on an N-channel notch filter and a negative resistor, and the high-order N-channel low-pass filter is used to suppress out-of-band blocking interference signals in the mixed signal.

[0024] It can be understood that the fourth-order gain-enhanced N-channel low-noise amplifier component includes a low-noise amplifier and a tunable fourth-order LC circuit. The low-noise amplifier can be any fourth-order gain-enhanced N-channel low-noise amplifier in the related art, and no specific limitation is made here. The low-noise amplifier is used to amplify the received RF signal, that is to say, the low-noise amplifier is used to amplify the RF signal received by the antenna. The LC circuit refers to any frequency-selective circuit composed of an inductor and a capacitor in the related art. Referring to Figure 1 , the tunable fourth-order LC circuit is connected in parallel with the low-noise amplifier, so that the low-noise amplifier component can achieve the purpose of being tunable, expand the bandwidth, and improve the suppression of out-of-band blocking interference signals. The switching mixer circuit refers to a circuit that adjusts the switching frequency to achieve the mixing function. The switching mixer circuit can generate a local oscillator signal. One set of the switching mixer circuits is used to mix the amplified RF signal and the local oscillator signal generated by the switching mixer circuit to obtain a mixed signal, that is, to down-convert the RF signal; the other set of the switching mixer circuits is used to determine the bandwidth of the receiving front-end architecture according to the local oscillator signal, that is, to determine the filtering bandwidth of the high-order N-channel low-pass filter. The high-order N-channel low-pass filter is generated based on an N-channel notch filter and a negative resistor. In an alternative embodiment, an improved N-channel capacitor-sharing notch filter (Modified N-Path Cap.-Shared Notch Filter) is used to generate stopband suppression, so as to be able to replace the baseband transimpedance amplifier, achieve attenuation suppression of out-of-band blocking signals, and maintain good in-band linearity.

[0025] In another embodiment of the present application, the anti-blocking SAW-less receivers are mainly divided into two categories: the first-stage mixer receiver and the low-noise amplifier-based receiver. Since the first-stage mixer receiver has no pre-stage gain amplification, its NF (noise factor) is poor. Therefore, the TIA (trans-impedance amplifier) of the first-stage mixer receiver usually has a relatively large power consumption to improve the gain and meet the impedance matching requirements. Although the NF requirement for the low-noise amplifier-based receiver is relatively loose, in order to achieve a better NF, the LNA (Low Noise Amplifier) often consumes more power budget, and both the LNA and TIA circuits are active circuits, which will deteriorate the in-band linearity.

[0026] The RF receiving front-end architecture used in the present application is as Figure 1 shown. The receiving front-end architecture includes a tunable fourth-order gain-enhanced N-channel (N-Path) LNA, a switching mixer circuit, and a reconfigurable high-order low-pass filter based on an N-Path Filter. In this receiving front-end architecture, the RF signal received from the antenna is amplified by the LNA, down-converted by the mixer circuit, and then instead of passing through a traditional TIA, a high-order LPF (low pass filter) based on an N-channel filter circuit is used to suppress out-of-band blocking interference signals. At the same time, since the LPF is a passive circuit, it can maintain a high in-band linearity. Therefore, the RF receiving front-end architecture of the present application provides a better trade-off among power consumption, linearity, and NF. In addition, since the high-order LPF of the present application is generated based on an N-channel notch filter, two sets of switching frequencies need to be provided. One set is used to down-convert the RF signal, and the other set is used to determine the bandwidth of the RF receiving front-end architecture. The switches can be driven by non-overlapping local oscillator signals with a 25% duty cycle.

[0027] In this embodiment, by adopting the RF receiving front-end architecture including the above-mentioned high-order N-channel low-pass filter, due to the frequency tunability of the fourth-order gain-enhanced N-channel low-noise amplifier component, the purpose of miniaturizing the RF receiving front-end is achieved. Moreover, the high-order N-channel low-pass filter replaces the trans-impedance amplifier to realize the attenuation and suppression of out-of-band blocking interference signals and maintain good in-band linearity.

[0028] In one embodiment, as Figure 2 shown, the RF receiving front-end architecture based on the high-order N-channel low-pass filter is further described. The low-noise amplifier is a low-noise amplifier designed based on an A / B class amplifier structure.

[0029] It can be understood that, in order to increase the transconductance g m and the current ID The ratio between them is used to design the LNA using the class A / B amplifier structure. The class A / B amplifier structure refers to any class A / B amplifier structure in the related art, which is not specifically limited herein. Compared with the self-biased class A amplifier, the LNA operating in the class A / B amplifier can achieve a larger transconductance at the same power consumption by reducing the bias voltage and increasing the device size, thereby achieving higher gain and lower NF. The fourth-order gain-enhanced N-Path low-noise amplifier based on class A / B amplification can achieve the same signal gain at lower power consumption, thus meeting the requirements of NF.

[0030] In one embodiment, as Figure 2 shown, a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter is further described. The low-noise amplifier includes an editable bias voltage, and the editable bias voltage is adjusted to improve the circuit non-linearity caused by the reduced conduction angle of the class A / B amplifier.

[0031] It can be understood that the circuit of the class A / B amplifier is an active circuit, and the reduction of the conduction angle of the class A / B amplifier will lead to the deterioration of in-band linearity. Referring to Figure 2 , by precisely editing the bias voltage V B , the circuit non-linearity caused by the reduction of the conduction angle of the class A / B amplifier can be improved.

[0032] In one embodiment, as Figure 2 shown, a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter is further described. The low-noise amplifier includes a replica circuit, and the replica circuit is used to stabilize the output bias voltage at half of the input power supply voltage.

[0033] It can be understood that the low-noise amplifier includes a replica circuit, and the structure of the replica circuit is as shown in the circuit of the right dashed box in Figure 2 . For the class A / B amplifier with a replica circuit, the output bias voltage can be stabilized at half of the input power supply voltage, thereby achieving the purpose of reducing the power consumption of the radio frequency receiving front-end architecture.

[0034] In one embodiment, as Figure 1 shown, a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter is further described. The tunable fourth-order LC circuit includes a parallel LC circuit and a series LC circuit. Among them, the parallel LC circuit is realized by a parallel capacitor and inductor, and the series LC circuit is realized by a series capacitor and inductor.

[0035] It can be understood that referring to Figure 1, an LC circuit refers to a circuit composed of an inductor and a capacitor. A tunable fourth-order LC circuit includes a parallel LC circuit and a series LC circuit. Among them, the parallel LC circuit is realized by a parallel-connected capacitor and inductor, and the series LC circuit is realized by a series-connected capacitor and inductor, so that the LC circuit can achieve a tunable function.

[0036] In one embodiment, as Figure 3 shown, a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter is further described. The tunable fourth-order LC circuit includes a parallel LC network, a series LC network, and an additional N-Path network. Among them, the parallel LC network and the additional N-Path network are both realized by N-Path circuits, and the series LC network is realized by a series N-Path circuit and a gyrator.

[0037] It can be understood that, referring to Figure 3 , by introducing a tunable fourth-order LC circuit around Gm,RF, due to the zeros generated by the high-order LC network, the LNA plays an important role in RF-BW extension and increasing the OOB (out-of-band) roll-off slope. In addition, the zero frequency can be tuned by the product of Gma and Gmb.

[0038] Among them, the tunable fourth-order LC circuit can be realized by a fourth-order N-Path network. Among them, the parallel LC network, that is, L P and C P are realized by N-Path circuits, while the series LC network, that is, L S and C S are realized by a series N-Path circuit and a gyrator, that is, Gma and Gmb. However, this LNA can only attenuate the blocking interference signals in the adjacent frequency band and cannot suppress the interference signals in the far-end frequency band. To solve this problem, an additional N-Path network, that is, an Extra Path network, is added between the LNA input and the gyrator output to sink the blocking signals in the far-end frequency band to the ground. The stopband impedance of this N-Path band-stop filter is selected to be much larger than the impedance of the fourth-order N-Path network. Therefore, for the communication frequency band, the Extra Path network does not affect the frequency response near the communication frequency band; while for the far-end frequency band, the impedance of the Extra Path network decreases, and the total impedance of the filter network decreases, realizing the suppression of the interference signals in the far-end frequency band. Finally, the proximal blocking interference signals will be severely attenuated by the zeros, and the far-end blocking currents will be eliminated through the additional path.

[0039] It should be noted that in the traditional RF front-end architecture, the mixer is almost one of the essential structural components. Due to its simplicity, low power consumption, and high linearity, the passive mixer is usually used more frequently than the active mixer. In order to reduce the noise introduced by the on-resistance of the switching transistors and improve the linearity of the mixer, the switching transistors are usually set to large sizes to approximate ideal switches. Therefore, the mixer driven by the local oscillator signal will generate relatively large dynamic power consumption due to its parasitic capacitance. In the receiving front-end architecture of this application, we utilize the circuit characteristics of the LNA with an additional filtering mechanism to extract the baseband signal, omitting the circuit structure for extracting the baseband signal from the traditional mixer. Since the switching transistor nodes for extracting the baseband signal come from the fourth-order LC gain-enhanced N-path network, it is possible to achieve the purpose of reducing the dynamic power consumption of the RF receiving front-end architecture.

[0040] In another embodiment of this application, referring to Figure 3 , since the parallel LC network, series LC network, and additional N-Path network in the tunable fourth-order LC circuit all include N-Path circuits, the baseband signal can be extracted from the N-Path circuit of the tunable fourth-order LC circuit. The tunable fourth-order LC circuit has the function of mixing, so the traditional mixer can be omitted.

[0041] In one embodiment, as Figure 5 shown, the RF receiving front-end architecture based on the high-order N-channel low-pass filter is further described. The circuit constituting the high-order N-channel low-pass filter is a passive circuit.

[0042] It can be understood that the LPF generated by the N-Path filter belongs to a passive circuit, so it can maintain good noise and linearity performance, and the main power consumption of the N-Path filter comes from the dynamic power consumption generated by the local oscillator signal drive.

[0043] It should be noted that due to the filtering circuit characteristics of the N-Path filter, the implemented compact LPF is convenient for integration and does not require additional large-size inductors.

[0044] In one embodiment, as Figure 5 shown, the RF receiving front-end architecture based on the high-order N-channel low-pass filter is further described. The high-order N-channel low-pass filter includes switched capacitors. Among them, in the high-order N-channel low-pass filter, two groups of differential signal paths share one switched capacitor.

[0045] It can be understood that the switched capacitor refers to any switched capacitor in the related art and is not specifically limited herein. Referring to Figure 4, there are mainly two types of common N-Path filters, namely N-Path BPF (N-Path Bandpass Filter, N-channel bandpass filter) and N-Path BSF (N-Path Bandstop Filter, N-channel bandstop filter). The tunable low-pass filter used in this application is generated by combining an N-channel notch filter and a negative resistance, as Figure 5 shown.

[0046] In a traditional N-channel bandstop filter, since there are switched capacitors on each path, it leads to an increase in chip area and chip cost. In addition, the parallel resistance Rp inherent in the equivalent circuit of the N-Path BSF will greatly reduce the stopband rejection and affect the filter performance. In the tunable LPF architecture, an improved N-channel capacitor-sharing notch filter is used to generate stopband rejection, as Figure 5 shown. In the capacitor-sharing notch filter, two sets of differential signal paths share a switched capacitor. That is to say, BB-LO1 and BB-LO3, BB-LO2 and BB-LO4 share a switched capacitor respectively, so that stopband rejection can be achieved, and only half of the capacitors of the traditional N-Path BSF are required, achieving the purpose of cost reduction; in addition, the LPF architecture of this application uses a negative transresistance based on a switched-capacitor circuit to cancel the influence of the positive parallel resistance in the N-Path circuit, enhancing the stopband rejection near the switching frequency and eliminating the limiting effect of the parallel resistance Rp.

[0047] In one embodiment, as Figure 5 shown, a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter is further described. The high-order N-channel low-pass filter further includes a shared capacitor.

[0048] It can be understood that referring to Figure 5 , the shared capacitor refers to a capacitor made of any material in the related art. The high-order N-channel low-pass filter further includes a shared capacitor. In an alternative embodiment, by adjusting the size of the shared capacitor C NR , the generated negative resistance can be adjusted to achieve an ideal parallel LC equivalent circuit.

[0049] It should be noted that due to the similarity between the switched-capacitor-based negative resistance circuit and the capacitor-sharing notch filter, these two circuits can be directly combined to implement a perfect N-channel notch filter.

[0050] In one embodiment, as Figure 5As shown, a radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter is further described. Bypass circuits with target capacitors are provided at both the input and output ports of the high-order N-channel low-pass filter, and the target capacitors are used to filter out high-frequency signals in the mixed-frequency signals.

[0051] It can be understood that the target capacitor refers to any capacitor in the related art. Bypass circuits with target capacitors are provided at both the input and output ports of the high-order N-channel low-pass filter, so that the target capacitor can be used to filter out high-frequency signals in the mixed-frequency signals, resulting in attenuation of the signal gain on the right side of the original notch, making the N-channel notch filter an adjustable low-pass filter.

Claims

1. A radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter, characterized in that Comprising: A fourth-order gain-enhanced N-channel low-noise amplifier component, the low-noise amplifier component including a low-noise amplifier and a tunable fourth-order LC circuit connected in parallel with the low-noise amplifier, the low-noise amplifier being used for amplifying the received radio frequency signal; Two sets of switch mixer circuits, one set of the switch mixer circuits being used for mixing the amplified radio frequency signal and the local oscillator signal generated by the switch mixer circuit to obtain a mixed signal; The other set being used for determining the bandwidth of the receiving front-end architecture according to the local oscillator signal; A high-order N-channel low-pass filter, the high-order N-channel low-pass filter being generated based on an N-channel notch filter and a negative resistor, the high-order N-channel low-pass filter being used for suppressing out-of-band blocking interference signals in the mixed signal; The low-noise amplifier is designed based on an A / B class amplifier structure, the low-noise amplifier including an editable bias voltage, and the editable bias voltage is adjusted to improve the circuit non-linearity caused by the reduction of the conduction angle of the A / B class amplifier; The low-noise amplifier includes a replica circuit, the replica circuit being used for stabilizing the output bias voltage at half of the input power supply voltage; The tunable fourth-order LC circuit includes a parallel LC network, a series LC network and an additional N-Path network, both the parallel LC network and the additional N-Path network are implemented by N-Path circuits, and the series LC network is implemented by a series N-Path circuit and a gyrator; the additional N-Path network is located between the input of the low-noise amplifier and the output of the gyrator; the baseband signal is extracted from the N-Path circuit of the tunable fourth-order LC circuit; The high-order N-channel low-pass filter includes two sets of differential signal paths, and the two sets of differential signal paths share a switched capacitor; The circuit constituting the high-order N-channel low-pass filter is a passive circuit.

2. The radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter according to claim 1, characterized in that The high-order N-channel low-pass filter further includes a shared capacitor.

3. The radio frequency receiving front-end architecture based on a high-order N-channel low-pass filter according to claim 1, wherein Bypass circuits with target capacitors are provided at both the input and output ports of the high-order N-channel low-pass filter, and the target capacitor is used for filtering high-frequency signals in the mixed signal.

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