Radio frequency performance test method, apparatus, and electronic device

Abstract

The application relates to the technical field of radio frequency testing, in particular to a radio frequency performance testing method and device and electronic equipment. The method comprises the following steps: obtaining structure information of a radio frequency front end to be tested; constructing a composite excitation signal, which is used for exciting the radio frequency front end; obtaining spatial complex field distribution information of at least one nonlinear response signal generated by the radio frequency front end excited by the composite excitation signal, and combining the structure information of the radio frequency front end to determine a propagation path of the nonlinear response signal from a generation source point in the radio frequency front end to a radiation point; positioning at least one target circuit node in the radio frequency front end according to the propagation path, and simultaneously determining a nonlinear distortion type caused by the target circuit node; and determining and outputting a test result according to the target circuit node and the nonlinear distortion type. The application can position the target circuit node causing the nonlinear distortion in the radio frequency front end, and solves the problem that the prior art cannot determine a specific fault position.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of radio frequency test, and in particular to a radio frequency performance test method and device and electronic equipment. BACKGROUND

[0002] As a key component in a wireless communication system, the performance of a radio frequency front end directly affects the signal transmission quality and reliability of the entire system. During the operation of the radio frequency front end, due to the nonlinear characteristics of internal active and passive devices, nonlinear distortions such as harmonic distortion and intermodulation distortion will inevitably occur, which will deteriorate the signal quality, interfere with adjacent channels, and even cause communication interruption. At present, the test method for the radio frequency front end usually uses a vector network analyzer or a spectrum analyzer and other devices to measure the excitation and response signals of the device ports to evaluate the overall nonlinear indicators of the radio frequency front end, such as the third-order intercept point and the harmonic suppression order.

[0003] However, this kind of black box test method can only quantitatively evaluate the overall nonlinear performance of the radio frequency front end, and when the test result does not meet the design requirements, it is impossible to determine which circuit nodes introduce the nonlinear distortion. In order to locate the fault source, researchers often need to rely on complex electromagnetic simulation or invasive on-the-road detection. The former is time-consuming and its accuracy depends on the accuracy of the model, and the latter may damage the device structure or introduce additional interference, affecting the accuracy of the test. Especially for highly integrated radio frequency chips or modules, the feasibility of physical detection is very low. SUMMARY

[0004] An object of an embodiment of the present application is to provide a radio frequency performance test method, device and electronic equipment to solve the technical problem that related technologies are difficult to locate the internal nonlinear distortion source point of the radio frequency front end.

[0005] In a first aspect, an embodiment of the present application provides a radio frequency performance test method, which comprises:

[0006] obtaining structure information of a radio frequency front end to be tested;

[0007] constructing a composite excitation signal, the composite excitation signal being used to excite the radio frequency front end;

[0008] obtaining spatial complex field distribution information of at least one nonlinear response signal generated by the radio frequency front end excited by the composite excitation signal, and combining the structure information of the radio frequency front end to determine the propagation path of the nonlinear response signal from the internal generation source point to the radiation point of the radio frequency front end;

[0009] locating at least one target circuit node in the radio frequency front end according to the propagation path, and determining the type of nonlinear distortion caused by the target circuit node;

[0010] determining and outputting a test result according to the target circuit node and the type of the nonlinear distortion.

[0011] With reference to the first aspect, in a possible implementation manner, the constructing the composite excitation signal comprises:

[0012] constructing a reference signal containing a plurality of discrete frequency components;

[0013] obtaining the composite excitation signal by configuring the frequency interval, amplitude ratio and phase relationship of each discrete frequency component in the reference signal, the composite excitation signal being used to synchronously excite the nonlinear response of the radio frequency front end at at least one harmonic frequency point or intermodulation frequency point in the operating frequency band.

[0014] With reference to the first aspect, in a possible implementation manner, the obtaining the spatial complex field distribution information of at least one nonlinear response signal generated by the composite excitation signal in the radio frequency front end comprises:

[0015] performing a predefined spatial scanning scheme to obtain amplitude and phase data of the nonlinear response signal at a plurality of spatial sampling points, the spatial scanning scheme being used to indicate a sequence of measurement points in the near-field region or the far-field region of the radio frequency front end, the density of the sequence of measurement points satisfying the sampling requirement of spatial frequency reconstruction of an equivalent radiation source of the radio frequency front end.

[0016] With reference to the first aspect, in a possible implementation manner, the determining the propagation path of the nonlinear response signal from a generation source point inside the radio frequency front end to a radiation point according to the spatial complex field distribution information and in combination with the structural information of the radio frequency front end comprises:

[0017] constructing an electromagnetic simulation model of known circuit connection relationship according to the structural information of the radio frequency front end;

[0018] taking the spatial complex field distribution information as a field constraint condition on the radiation boundary of the electromagnetic simulation model, and determining virtual source distribution information of an equivalent radiation field generated inside the radio frequency front end by solving the electromagnetic simulation model;

[0019] determining the propagation path of the nonlinear response signal from the generation source point inside the radio frequency front end to the radiation point according to the virtual source distribution information and the circuit connection relationship.

[0020] With reference to the first aspect, in a possible implementation manner, the locating at least one target circuit node inside the radio frequency front end according to the propagation path comprises:

[0021] According to the propagation path, a signal transmission link is determined, the signal transmission link sequentially indicates each node through which the nonlinear response signal passes in signal transmission order;

[0022] A spatial complex field distribution feature corresponding to a main frequency component of the nonlinear response signal is extracted, the spatial complex field distribution feature including amplitude and phase variation characteristics of the nonlinear response signal;

[0023] The spatial complex field distribution feature is matched and calculated with a pre-stored feature library, one or more candidate circuit nodes with a matching degree higher than a preset matching threshold are screened from the feature library, and the feature library stores theoretical spatial field distribution features of a plurality of typical nonlinear circuit node failures;

[0024] The candidate circuit node located in the signal transmission link is determined as the target circuit node.

[0025] In combination with the first aspect, in a possible implementation manner, the determination of the nonlinear distortion type caused by the target circuit node includes:

[0026] A signal component corresponding to the target circuit node is separated from the spatial complex field distribution information;

[0027] If a dominant frequency component of the signal component is an integer multiple of a single frequency component in the composite excitation signal, it is determined that the nonlinear distortion type is a harmonic distortion type;

[0028] If a dominant frequency component of the signal component is a sum, difference or combination of two or more frequency components in the composite excitation signal, it is determined that the nonlinear distortion type is an intermodulation distortion type.

[0029] In combination with the first aspect, in a possible implementation manner, before the spatial complex field distribution information is acquired, the method further includes:

[0030] The preset calibration piece is excited by the composite excitation signal;

[0031] Spatial complex field distribution information of the nonlinear response signal generated by the calibration piece is acquired as reference data;

[0032] The spatial complex field distribution information of the composite excitation signal excited in the radio frequency front end is compared with the reference data to eliminate nonlinear background noise and channel response errors.

[0033] In combination with the first aspect, in a possible implementation manner, the method further includes:

[0034] According to the test result, the configuration of the composite excitation signal is adjusted to generate a second excitation signal;

[0035] continuously excite the radio frequency front end using the second excitation signal to obtain a verification result;

[0036] compare the verification result with the test result to determine whether a position deviation of a same target circuit node exceeds a preset threshold value;

[0037] if the position deviation does not exceed the preset threshold value, determine that the test result is valid;

[0038] if the position deviation exceeds the preset threshold value, mark the test result as pending to start a new round of diagnosis process.

[0039] In a second aspect, the embodiments of the present application further provide a radio frequency performance testing device, comprising:

[0040] a data acquisition module configured to acquire structural information of a radio frequency front end to be tested;

[0041] a signal construction module configured to construct a composite excitation signal, wherein the composite excitation signal is used to excite the radio frequency front end;

[0042] an excitation response module configured to acquire spatial complex field distribution information of at least one nonlinear response signal generated by the radio frequency front end under the excitation of the composite excitation signal, and determine a propagation path of the nonlinear response signal from a generation source point inside the radio frequency front end to a radiation point in combination with the structural information of the radio frequency front end;

[0043] a node positioning module configured to position at least one target circuit node inside the radio frequency front end and determine a type of nonlinear distortion caused by the target circuit node;

[0044] a test output module configured to determine and output a test result according to the target circuit node and the type of nonlinear distortion.

[0045] In a third aspect, the embodiments of the present application further provide an electronic device comprising a memory and a processor, wherein the memory is connected to the processor, and the processor is configured to execute one or more computer programs stored in the memory, and when the one or more computer programs are executed, the processor enables the electronic device to implement the radio frequency performance testing method according to the first aspect.

[0046] The embodiments of the present application can achieve the following technical effects:

[0047] This application embodiment acquires the spatial complex field distribution information of the nonlinear response signal to capture the complete radiation characteristics of the nonlinear distortion signal in the external space of the device. By combining the spatial complex field distribution information with the structural information of the RF front-end under test, and determining the propagation path of the signal from the internal source point to the radiation point, a physical mapping relationship between the external measurable radiation field and the internal invisible source point is successfully constructed. This overcomes the limitations of traditional black box testing and can locate the target circuit node that generates nonlinear distortion inside the RF front-end, solving the problem that the existing technology cannot determine the specific fault location. Attached Figure Description

[0048] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 A flowchart illustrating a radio frequency performance testing method provided in an embodiment of this application;

[0050] Figure 2 A schematic diagram of the frame of a radio frequency performance testing device provided in an embodiment of this application;

[0051] Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0053] It should be noted that, unless there is a conflict, the various features in the embodiments of this application can be combined with each other, all of which are within the protection scope of this application. Furthermore, although functional modules are divided in the system diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than the module division in the system or the order in the flowchart. Moreover, the terms "first," "second," and "third" used in this application do not limit the data or execution order, but only distinguish identical or similar items with essentially the same function and effect.

[0054] This application provides a radio frequency (RF) performance testing method designed to address the black-box testing problem in existing RF front-end (RFFE) testing methods. Traditional testing methods typically only measure overall performance indicators (such as harmonics and intermodulation distortion) at the port, failing to accurately pinpoint the specific circuit nodes or structures causing performance degradation. This application, through a cause-and-effect approach, traces the source and propagation path of the nonlinear response signal from its external field distribution back into the circuit, thereby achieving precise location and diagnosis of nonlinear distortion sources within the RF front-end.

[0055] Figure 1 A flowchart illustrating a radio frequency performance testing method according to an embodiment of this application is shown. Figure 1 As shown, the above method includes steps S10-S50:

[0056] Step S10: Obtain the structural information of the radio frequency front-end under test;

[0057] Step S20: Construct a composite excitation signal, which is used to excite the radio frequency front end;

[0058] Step S30: Obtain the spatial complex field distribution information of at least one nonlinear response signal generated by the radio frequency front-end excited by the composite excitation signal, and determine the propagation path of the nonlinear response signal from the generation source point inside the radio frequency front-end to the radiation point in combination with the structural information of the radio frequency front-end.

[0059] Step S40: Based on the propagation path, locate at least one target circuit node inside the radio frequency front end, and simultaneously determine the type of nonlinear distortion caused by the target circuit node.

[0060] Step S50: Determine and output the test results based on the target circuit node and the nonlinear distortion type.

[0061] This embodiment uses the testing of an RF front-end module applied to a 5G communication terminal as an example. This module integrates at least power amplifiers, low-noise amplifiers, switches, and filters. The purpose of testing it is to locate the specific circuit units that cause out-of-band nonlinear distortion (such as harmonics and intermodulation products) and their root causes.

[0062] In this embodiment, the structural information of the radio frequency front-end module under test (RF front-end) is first obtained as the basis for propagation path analysis and source location in subsequent steps.

[0063] For example, the structural information of the radio frequency front end includes:

[0064] Physical layout information, i.e. the physical layout design file of the chip or module of the radio frequency front-end, such as a GDSII or OASIS format file, which includes the precise geometry, size and physical location of all transistors, capacitors, inductors, resistors and other components inside the chip, as well as the layout of the metal interconnection traces.

[0065] Circuit netlist information, i.e. the circuit schematic netlist corresponding to the above-mentioned physical layout, such as a SPICE netlist. The netlist defines the electrical connection relationship between all components and assigns a unique identifier to each component (e.g. transistor Q1, capacitor C5).

[0066] Three-dimensional packaging and PCB information, i.e. the layout information of the packaging model (such as BGA solder ball layout) of the radio frequency front-end and the printed circuit board (PCB) to which it is soldered (such as an ODB++ format file), such as packaging substrate, bonding wire, PCB trace, via and other three-dimensional structures.

[0067] As a preferred embodiment, the above-mentioned physical layout information, circuit netlist information and three-dimensional packaging information can be integrated by professional EDA software to construct a three-dimensional digital model integrating electricity-magnetism-structure. This model can accurately map any coordinate point in the physical space to a specific circuit node (such as the gate of transistor Q1) or a section of transmission line in the circuit netlist.

[0068] On this basis, in order to effectively stimulate the nonlinear effects inside the radio frequency front-end, the embodiment constructs a composite excitation signal that can simulate real working scenarios or be used for diagnosis.

[0069] Exemplarily, the embodiment adopts a dual-tone signal as the composite excitation signal, which is specifically set as:

[0070] Tone 1 (f1): 3.50 GHz, power +5 dBm;

[0071] Tone 2 (f2): 3.51 GHz, power +5 dBm.

[0072] The dual-tone signal can be generated by a vector signal generator and input to the input port of the radio frequency front-end through a radio frequency cable. The purpose of selecting the dual-tone signal in this embodiment is to simultaneously stimulate harmonic distortion (such as second-order harmonics 2f1, 2f2, third-order harmonics 3f1, 3f2) and intermodulation distortion (such as third-order intermodulation products IMD3: 2f1-f2=3.49 GHz and 2f2-f1=3.52 GHz).

[0073] In addition, the composite excitation signal can also be a wideband communication signal, for example, a 5G NR uplink signal with a bandwidth of 100 MHz (using 64-QAM modulation), to better simulate the nonlinear effects of the radio frequency front end under actual working conditions, such as spectral regeneration and adjacent channel leakage power ratio.

[0074] In this embodiment, when the composite excitation signal excites the radio frequency front end, the nonlinear response signal (such as the IMD3 signal) generated by the internal nonlinear source points will not only propagate to the antenna port through the preset radio frequency channel, but also may be coupled and radiated through the parasitic path to form a specific electromagnetic field distribution on the module surface and in the surrounding space.

[0075] Based on this understanding, the spatial complex field distribution information acquisition method includes, for example:

[0076] A high-precision near-field scanning system is arranged near the radio frequency front end, which at least includes a three-dimensional moving platform, an electric field or magnetic field probe, and a vector signal analyzer or a spectrum analyzer;

[0077] The radio frequency front end to be tested is placed on the workbench of the scanning system and is made to work under the above excitation conditions;

[0078] The center frequency of the vector signal analyzer or the spectrum analyzer is set to the nonlinear response signal frequency, for example, the third-order intermodulation frequency 3.49 GHz (IMD3);

[0079] The probe is controlled to perform two-dimensional grid scanning on a preset plane (for example, a height of 1 mm from the module surface) above the radio frequency front end. At each scanning point (x, y), the vector signal analyzer or the spectrum analyzer measures and records the amplitude and phase information of the electromagnetic field at the point to obtain the spatial complex field distribution data E(x, y) or H(x, y) of the IMD3 signal on the plane.

[0080] The spatial complex field distribution data E(x, y) or H(x, y) obtained in the above step is used as a boundary condition for solving by using an electromagnetic field reverse propagation algorithm. For example, using the electric-magnetic-structure integrated three-dimensional digital model constructed in the above embodiment, the propagation trajectory of the electromagnetic wave is calculated in reverse from the measurement plane by using the finite difference time domain (FDTD) or the method of moments (MoM).

[0081] Since the digital model includes all conductive structures (metal traces, component pins, ground planes, etc.) in the radio frequency front end, the reverse propagation algorithm can simulate how the IMD3 signal energy is propagated from its source, along a specific microstrip line, coplanar waveguide, or through spatial coupling, to the outside and captured by the probe.

[0082] The output of the algorithm is one or more three-dimensional energy propagation paths, whose starting point is the region of energy concentration, i.e. the source point of the non-linear signal; the end point is the main radiation point or the measurement point.

[0083] For example, the result of the solution shows that the IMD3 signal energy mainly propagates along a specific microstrip line of the PA output matching network, and there is a significant leakage near an inductive element.

[0084] On this basis, the target circuit node involved in the propagation process is determined by the embodiment.

[0085] For example, the physical coordinates of the starting point of the energy propagation path (e.g. x = 1.2 mm, y = 2.5 mm, z = 0.1 mm) are compared with the digital model constructed in the above embodiment, and the model query result shows that the coordinates correspond to the collector node of the final-stage amplifier of the module. Therefore, the collector of the transistor is determined as the target circuit node of the test.

[0086] Further, it is assumed that the tracked signal is a third-order intermodulation product with a frequency of 2f1-f2, and according to the non-linear theory, the third-order intermodulation distortion is caused by the third-order non-linear term (a3 x^3) of the circuit transfer function. Therefore, it can be determined that significant third-order non-linear distortion occurs at the target circuit node, which is usually related to the third-order derivative effect of the gain compression or transconductance of the transistor.

[0087] The embodiment finally integrates all the information analyzed in the above process into the test result output.

[0088] Exemplarily, the test result specifically includes:

[0089] Problem positioning: it is pointed out that the main reason for the deterioration of the IMD3 index is the final-stage amplifier (such as device number: Q_final_stage) of the power amplifier;

[0090] Distortion mechanism: it is pointed out that the fundamental reason is that the collector node of the transistor produces significant third-order non-linear distortion under the current operating bias and input power, which shows strong gain compression effect;

[0091] Path analysis: that is, the propagation path diagram of the non-linear signal, for example, it shows that after the IMD3 signal is generated from the collector of the transistor Q_final_stage, it propagates through the output matching network, and there is parasitic radiation near the matching inductor, which aggravates the out-of-band emission.

[0092] More specifically, the output form of the test result is specifically:

[0093] Layout or 3D model of the RF front-end, and mark the located target circuit node (PA final stage Q_final_stage) on the figure in the form of highlight or heat map;

[0094] At the same time, visualize the propagation path of the IMD3 signal from the node to the external space, and describe the type of nonlinear distortion (third-order intermodulation distortion) and its possible physical causes through textual description.

[0095] Compared with the traditional black box test method of only measuring indicators at the RF port, the application embodiment provides a more accurate diagnosis method, which reverses the internal circuit source from the spatial field distribution technology, can greatly shorten the debugging cycle of RF chips and modules, guide the design engineers to carry out accurate and efficient optimization, and thus accelerate the product research and development process.

[0096] Further, in the above embodiment, the composite excitation signal is constructed, comprising:

[0097] Constructing a reference signal, the reference signal containing a plurality of discrete frequency components;

[0098] By configuring the frequency interval, amplitude ratio and phase relationship of each discrete frequency component in the reference signal, the composite excitation signal is obtained, which is used to synchronously excite the nonlinear response of the RF front-end at at least one harmonic frequency point or intermodulation frequency point in the working frequency band.

[0099] The RF front-end module in the above embodiment is taken as the test object. It is assumed that the working frequency band of the module is 3.4GHz to 3.6GHz, and the test target is to accurately evaluate and locate the nonlinear distortion generated by the PA at the center point f_target = 3.5 GHz of the working frequency band.

[0100] The reference signal in this embodiment is a set of single-tone signals selected by special frequency, and the principle of determining each frequency component is that the frequency of the specific order harmonic or intermodulation product generated by each frequency after nonlinear conversion through the PA is exactly equal to the preset target frequency f_target.

[0101] For example, in order to synchronously excite multiple nonlinear responses at f_target = 3.5 GHz, the following frequency components can be selected to constitute the reference signal:

[0102] The component for exciting the second-order harmonic (H2) is selected to have a frequency of:

[0103] f_H2 = f_target / 2 = 3.5 GHz / 2 = 1.75 GHz tone.

[0104] When this tone passes through the module, it generates a second order harmonic 2 f_H2 will fall exactly at 3.5 GHz.

[0105] Note: 1.75 GHz is outside the operating band of the PA, but this is one of the features of this method, namely to use out-of-band excitation to probe the in-band response.

[0106] To excite the third order harmonic (H3) component, select a tone with a frequency of:

[0107] f_H3 = f_target / 3 ≈ 1.1667 GHz.

[0108] When this tone passes through the PA, it generates a third order harmonic 3 f_H3 will also fall exactly at 3.5 GHz.

[0109] To excite the third order intermodulation (IMD3) component:

[0110] Select a pair of tones with frequencies f_IMD_a and f_IMD_b such that they satisfy the third order intermodulation formula:

[0111] 2 f_IMD_a - f_IMD_b = f_target or 2 f_IMD_b - f_IMD_a = f_target.

[0112] For convenience, select a pair of tones near the operating band, for example:

[0113] Let f_IMD_a = 3.6 GHz;

[0114] Let f_IMD_b = 3.7 GHz;

[0115] When these two tones are simultaneously input to the module, it will generate a third order intermodulation product with a frequency of:

[0116] 2 3.6 GHz - 3.7 GHz = 7.2 GHz - 3.7 GHz = 3.5 GHz.

[0117] Thus, the reference signal is composed of these four discrete frequency components:

[0118] { 1.1667 GHz, 1.75 GHz, 3.6 GHz, 3.7 GHz}.

[0119] After the frequency components of the reference signal are determined, the complex excitation signal with specific diagnostic purpose is formed by configuring the amplitude and phase of each frequency component.

[0120] As mentioned above, the interval between each frequency component is determined by the target of making the nonlinear products converge at a single target frequency.

[0121] Since the strength of nonlinear effects of different orders is different, the strength of the nonlinear response contributed by each frequency component at f_target can be controlled by adjusting the input power of each frequency component.

[0122] Specifically, the amplitudes of the nonlinear responses from different sources at the target frequency point are roughly equivalent, which facilitates subsequent analysis or separation.

[0123] Exemplarily, it is configured as:

[0124] P(f_H2 = 1.75 GHz) = -5 dBm (second-order effect is usually stronger, and lower power is used for excitation);

[0125] P(f_H3 = 1.1667 GHz) = 0 dBm;

[0126] P(f_IMD_a = 3.6 GHz) = +3 dBm;

[0127] P(f_IMD_b = 3.7 GHz) = +3 dBm (intermodulation effect usually requires higher power).

[0128] Through this configuration, at 3.5 GHz at the module output, amplitude-comparable response signals from the second-order harmonic, the third-order harmonic, and the third-order intermodulation can be observed simultaneously.

[0129] At the same time, in order to make all nonlinear products in-phase at f_target to produce the most easily measured response signal, the initial phase of the input signal is adjusted in this embodiment.

[0130] For example, through pre-calibration or calculation, the input phase is set so that at f_target = 3.5 GHz at the module output, the phase of all the above-mentioned response signals is 0 degrees (or any same angle).

[0131] Assuming that the phase delay of the module has been calibrated and compensated, at this time, the following settings are made:

[0132] Phase(f_H2 input) = 0;

[0133] Phase(f_H3 input) = 0;

[0134] Phase(f_IMD_a input) = 0;

[0135] Phase(f_IMD_b input) = 0;

[0136] Consequently, all nonlinear product components will be superimposed in phase at 3.5 GHz, maximizing the total nonlinear response energy.

[0137] This embodiment also allows for the separation of different nonlinear sources through phase control. For example, by keeping the response phases of H3 and IMD3 at 0 degrees, but adjusting the response phase of H2 to 90 or 180 degrees, the contributions from H2, H3, and IMD3 can be accurately separated through phasor decomposition, thereby determining which nonlinear mechanism dominates in the PA.

[0138] Finally, the multiple tone signals, which have been precisely configured in terms of frequency, amplitude, and phase, are combined into a single time-domain waveform using an arbitrary waveform generator or a multi-channel vector signal generator, which serves as the final composite excitation signal for the excitation module.

[0139] This embodiment designs an excitation signal containing multiple discrete frequency components, enabling nonlinear distortion products of different orders (such as harmonics and intermodulation) inside the RF front-end under test to be superimposed at a specific target frequency point within the operating frequency band. This achieves synchronous and amplified excitation of nonlinear effects, greatly improving the sensitivity of the test and the accuracy of the diagnosis.

[0140] Furthermore, acquiring the spatial complex field distribution information of at least one nonlinear response signal generated by the composite excitation signal in the radio frequency front end includes:

[0141] A predefined spatial scanning scheme is executed to obtain the amplitude and phase data of the nonlinear response signal at multiple spatial sampling points. The spatial scanning scheme is used to indicate the sequence of measurement points in the near-field or far-field region of the radio frequency front-end radiation. The density of the sequence of measurement points meets the sampling requirements for spatial frequency reconstruction of the equivalent radiation source of the radio frequency front-end.

[0142] In this embodiment, a near-field scanning system is used to perform a predefined spatial scanning scheme during measurement. The system includes a three-dimensional robotic arm controlled by a stepper motor and an electric field probe connected to a vector network analyzer.

[0143] In this embodiment, a scanning scheme is preset. Taking planar grid scanning as an example, the radio frequency front-end under test (RF-FEM) is fixed on the test stage, and the robotic arm is instructed to move the probe within a 5cm x 5cm planar area 2mm above the RF front-end.

[0144] The instruction measurement point sequence is to start from the coordinates (x=0, y=0) and perform a raster scan with a fixed step (for example, Δx=0.5mm, Δy=0.5mm) until the entire preset plane is covered.

[0145] It is easy to understand that the sampling requirement that meets the spatial frequency reconstruction follows the spatial sampling theorem (an extension of the Nyquist criterion in the spatial domain). In order to be able to reconstruct the equivalent radiation source of the nonlinear signal without distortion, the scanning step must be less than half a wavelength (λ / 2). Wherein, λ refers to the wavelength corresponding to the fastest change (the highest spatial frequency) that can exist on the surface of the radio frequency front end.

[0146] In order to accurately capture the details of the radiation field generated by the microcircuit structure (such as the transistor pin), a step much smaller than the free space wavelength is preferred, for example, for a nonlinear signal of 3.5GHz (free space wavelength about 8.5cm), we choose a step of 0.5mm to ensure that the millimeter or even sub-millimeter level of the radiation source details can be reconstructed.

[0147] At each (x, y) sampling point, the vector network analyzer locks on the nonlinear response frequency, measures and records the amplitude and phase of the electric field at this point, and finally obtains a two-dimensional matrix containing all the sampling point complex field data, that is, the spatial complex field distribution information.

[0148] Further, the method further comprises:

[0149] According to the structure information of the radio frequency front end, an electromagnetic simulation model with known circuit connection relationship is constructed;

[0150] The spatial complex field distribution information is used as the field constraint condition on the radiation boundary of the electromagnetic simulation model, and by solving the electromagnetic simulation model, the virtual source distribution information of the equivalent radiation field generated inside the radio frequency front end is determined;

[0151] According to the virtual source distribution information and the circuit connection relationship, the propagation path of the nonlinear response signal from the generation source point inside the radio frequency front end to the radiation point is determined.

[0152] As described in the above embodiment, the 3D model of the physical layout of the radio frequency front end, the package and the PCB is imported into the software, and combined with the circuit netlist, a three-dimensional electromagnetic model containing all conductive structures such as metal traces, vias, and device pads is constructed, which has accurate circuit connection relationship.

[0153] The spatial complex field distribution data measured in the previous step is used as the boundary condition for the simulation model on the virtual measurement surface (which coincides with the actual measurement plane). Then, field propagation inversion is enabled. This algorithm solves Maxwell's equations to calculate the equivalent current and charge distribution that must exist on the metal structure inside the model in order to generate the measured field distribution at the boundary. This distribution is the virtual source distribution information.

[0154] In this embodiment, the virtual source distribution information is overlaid on the 3D model in the form of a heatmap, with highlighted areas representing areas where nonlinear signal energy (current) is concentrated. First, the region with the strongest energy is identified; this region is the source point of the nonlinear signal. Then, since the model knows the connections of all circuits, the energy flow trajectory can be traced along the path with the highest current density, starting from the source point and following the interconnected metal traces until the main radiation point of the signal (such as the antenna port or a leaking component). The traced energy flow trajectory is the desired propagation path.

[0155] Furthermore, locating at least one target circuit node within the radio frequency front end according to the propagation path includes:

[0156] Based on the propagation path, a signal transmission link is determined, and the signal transmission link sequentially indicates each node through which the nonlinear response signal passes in the order of signal transmission;

[0157] Extract the spatial complex field distribution features corresponding to the main frequency components of the nonlinear response signal, wherein the spatial complex field distribution features include the amplitude and phase variation features of the nonlinear response signal;

[0158] The spatial complex field distribution features are matched with a pre-stored feature library. One or more candidate circuit nodes with a matching degree higher than a preset matching threshold are selected from the feature library. The feature library stores theoretical spatial field distribution features of various typical nonlinear circuit nodes when they fail.

[0159] The candidate circuit node located in the signal transmission link is determined as the target circuit node.

[0160] It is easy to understand that the propagation path determined in the above embodiments is itself a signal transmission link. For example, the path shows that the signal starts from the collector of transistor Q5, passes through microstrip line TL10, flows through inductor L3, and finally reaches the output port.

[0161] Based on this, the field distribution around the located source point (the starting point of the propagation path) is analyzed, and its local spatial fingerprint is extracted as a feature of the spatial complex field distribution. For example, this fingerprint includes: the peak shape of the field strength, the attenuation gradient of the field strength, and the rotation or jump characteristics of the phase around the source point.

[0162] The extracted spatial fingerprint is then pattern-matched against a pre-established library of signatures (e.g., using a two-dimensional cross-correlation algorithm). The library stores theoretical or measured spatial field distribution signatures of various typical circuit nodes when they are subject to non-linear failure, such as:

[0163] Library entry 1: HBT transistor gain compression signature - presents a specific dipole radiation field pattern near the collector, with characteristic distortion in phase;

[0164] Library entry 2: MEMS switch contact non-linearity signature - has a strong local electric field concentration at the switch contact gap, with significant variation in field strength with bias voltage;

[0165] If the matching calculation result shows that the extracted spatial fingerprint has a cross-correlation coefficient of up to 95% with the HBT transistor gain compression signature, far exceeding the pre-set matching threshold (e.g., 80%), and the location is at the start of the signal transmission link, then transistor Q5 is finally determined as the target circuit node for this test.

[0166] Further, the determination of the type of non-linear distortion caused by the target circuit node includes:

[0167] Separating the signal component corresponding to the target circuit node from the spatial complex field distribution information;

[0168] If the dominant frequency component of the signal component is an integer multiple of a single frequency component in the composite excitation signal, then the type of non-linear distortion is determined to be harmonic distortion type;

[0169] If the dominant frequency component of the signal component is the sum, difference, or combination of two or more frequency components in the composite excitation signal, then the type of non-linear distortion is determined to be intermodulation distortion type.

[0170] Specifically, if the composite excitation signal contains one frequency component f_in = 1.75 GHz, and the measured response frequency f_resp = 3.5 GHz.

[0171] Since this response frequency satisfies the relationship f_resp = n f_in (where n = 2, an integer), it is determined that the type of non-linear distortion caused by the target circuit node Q5 is second-order harmonic distortion;

[0172] If the composite excitation signal contains two frequency components f_in1 = 3.6 GHz and f_in2 = 3.7 GHz, and the measured response frequency f_resp = 3.5 GHz. Since this response frequency satisfies the relationship:

[0173] f_resp = 2 f_in1 - 1 f_in2 (is a linear combination of two input frequencies), then the type of non-linear distortion caused by the target circuit node Q5 is third-order intermodulation distortion.

[0174] Further, before acquiring the spatial complex field distribution information, the method further comprises:

[0175] exciting a preset calibration piece with the composite excitation signal;

[0176] acquiring spatial complex field distribution information of a non-linear response signal generated by the calibration piece as reference data;

[0177] comparing the spatial complex field distribution information excited by the composite excitation signal in the radio frequency front end with the reference data to eliminate non-linear background noise and channel response errors.

[0178] In the embodiment, before formally testing the to-be-tested radio frequency front end, a standard calibration piece (for example, a Schottky diode with a package and pins similar to a key transistor in the to-be-tested device) with known non-linear characteristics is placed at the same position. The calibration piece is excited using the same composite excitation signal as the main test, and the same spatial scanning process is performed to acquire spatial complex field distribution of a non-linear response signal, which is recorded as reference data E_ref(x, y). The data serves as a non-linear fingerprint of the entire test system (including a signal source, a cable, a probe, and stray reflections in a test environment).

[0179] The to-be-tested radio frequency front end is measured to obtain an original spatial complex field distribution E_dut(x, y). E_dut(x, y) is corrected by comparing E_ref(x, y) to filter out noise and errors of E_dut(x, y).

[0180] Specifically, the corrected field distribution information E_corr(x, y) is obtained according to the following formula:

[0181] E_corr(x, y) = E_dut(x, y) - E_ref(x, y).

[0182] The embodiment effectively eliminates the non-linear background noise of the common mode and the fixed channel response error, so that E_corr(x, y) can more truly reflect the non-linear effect generated by the to-be-tested radio frequency front end itself.

[0183] Further, the method of the above embodiment further comprises:

[0184] According to the test result, the configuration of the composite excitation signal is adjusted to generate a second excitation signal;

[0185] using the second excitation signal to stimulate the radio frequency front end again, and obtaining a verification result;

[0186] comparing the verification result with the test result to determine whether a position deviation of the same target circuit node exceeds a preset threshold value;

[0187] if the position deviation does not exceed the preset threshold value, determining that the test result is valid;

[0188] if the position deviation exceeds the preset threshold value, marking the test result as pending to start a new round of diagnosis process.

[0189] For example, assuming that the first round of test (using 3.6 GHz and 3.7 GHz dual tones) locates transistor Q5 as the main source of IMD3. To verify this conclusion, the second excitation signal is further designed in this embodiment.

[0190] For example, a single tone signal with a frequency of 1.1667 GHz is used, and the purpose is to stimulate a different type of nonlinear response, i.e. third-order harmonic, at the same target frequency of 3.5 GHz. The radio frequency front end is stimulated again using the second excitation signal, and the complete test process (scanning, inversion, positioning) is repeated to obtain a source point position based on the third-order harmonic response.

[0191] On this basis, the position deviation D between the IMD3 source point coordinate P_IMD3(x1, y1) located in the first round of test and the H3 source point coordinate P_H3(x2, y2) located in this round of verification is calculated.

[0192] In this embodiment, a physical threshold value related to the feature size of the device is preset, for example, 50 microns (which is generally the approximate size of an effective area of a transistor), and if the position deviation D is less than 50 microns, it indicates that the two types of nonlinear distortions are directed to the same microscopic physical position, and thus it is determined that the test result is valid.

[0193] If the position deviation D is significantly greater than 50 microns, it may mean that there are multiple different nonlinear sources in the device, or that the initial diagnosis is biased. At this time, the test result is marked as pending, and a new round of diagnosis process can be started.

[0194] For details, please refer to Figure 2 The embodiment of the present application also provides a radio frequency performance test device, comprising:

[0195] The data acquisition module 210 is configured to acquire the structure information of the radio frequency front end to be tested.

[0196] The signal construction module 220 is configured to construct a composite excitation signal, and the composite excitation signal is used to stimulate the radio frequency front end.

[0197] The excitation response module 230 is configured to acquire spatial complex field distribution information of at least one nonlinear response signal generated by the radio frequency front end under the excitation of the composite excitation signal, and determine a propagation path of the nonlinear response signal from a generation source point inside the radio frequency front end to a radiation point in combination with structure information of the radio frequency front end.

[0198] The node positioning module 240 is configured to position at least one target circuit node inside the radio frequency front end, and determine a type of nonlinear distortion caused by the target circuit node.

[0199] The test output module 250 is configured to determine and output a test result according to the target circuit node and the type of nonlinear distortion.

[0200] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process and related description of the apparatus can be referred to the corresponding process in the foregoing method embodiments, which will not be described herein.

[0201] Further, referring to Figure 3 , Figure 3 is a structural schematic diagram of an electronic device provided by an embodiment of the present application. The electronic device 60 includes one or more processors 61 and a memory 62. The memory 62 is connected to the one or more processors 61, for example, connected to the processor 61 through a bus.

[0202] The processor 61 is configured to support the electronic device to perform the corresponding functions in the methods in the foregoing method embodiments. The processor 61 can be a central processing unit (CPU), a network processor (NP), a hardware chip or any combination thereof. The hardware chip can be an application specific integrated circuit (ASIC), a programmable logic device (PLD) or a combination thereof. The PLD can be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL) or any combination thereof.

[0203] The memory 62 is configured to store program codes and the like. The memory 62 can include a volatile memory (VM), for example, a random access memory (RAM); the memory 62 can also include a non-volatile memory (NVM), for example, a read-only memory (ROM), a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD); and the memory 62 can further include a combination of the above-mentioned memories.

[0204] The memory 62 can be configured to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as program instructions / modules corresponding to the radio frequency performance test method in the embodiments of the present application. The processor 61 executes the radio frequency performance test method and various functional applications and data processing of the UI interface generation system by running the non-volatile software programs, instructions, and modules stored in the memory 62, that is, the functions of each module or unit of the radio frequency performance test method and the UI interface generation system provided in the method embodiments are implemented.

[0205] The memory 62 can include a program storage area and a data storage area, where the program storage area can store an operating system and application programs required by at least one function. The data storage area can store data created according to the use of the UI interface generation system, and the like. In some embodiments, the memory 62 can optionally include a memory remotely disposed relative to the processor 61, and these remote memories can be connected to the UI interface generation device through a network. Examples of the network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0206] One or more modules are stored in the memory 62, and when executed by the one or more processors 61, the radio frequency performance test method in any of the above method embodiments is performed, for example, the method steps described in the above method embodiments are executed, and the functions of the modules described in the above system embodiments are implemented.

[0207] The embodiments of the present application further provide a computer-readable storage medium, which stores a computer program, and the computer program includes program instructions. When the program instructions are executed by a processor of an electronic device, the processor executes the radio frequency performance test method as described in the foregoing embodiments.

[0208] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by a computer program instructing relevant hardware, and the program can be stored in a computer readable storage medium. When the program is executed, the program can include the processes of the above-mentioned embodiment methods. The storage medium can be a magnetic disc, an optical disc, a read-only memory (ROM), a random access memory (RAM), or the like.

[0209] The above disclosure is only the preferred embodiment of the present application, and of course cannot limit the scope of the right of the present application, so the equivalent changes made according to the claims of the present application still belong to the scope covered by the present application.

Claims

1. A method for testing radio frequency performance, characterized in that, include: Obtain the structural information of the RF front-end under test; A composite excitation signal is constructed to excite the radio frequency front end; The spatial complex field distribution information of at least one nonlinear response signal generated by the radio frequency front-end excited by the composite excitation signal is obtained, and combined with the structural information of the radio frequency front-end, the propagation path of the nonlinear response signal from the generation source point inside the radio frequency front-end to the radiation point is determined. Based on the propagation path, at least one target circuit node is located inside the radio frequency front end, and the type of nonlinear distortion caused by the target circuit node is determined. Based on the target circuit node and the type of nonlinear distortion, the test results are determined and output.

2. The method according to claim 1, characterized in that, The construction of the composite excitation signal includes: Construct a reference signal, which contains multiple discrete frequency components; The composite excitation signal is obtained by configuring the frequency interval, amplitude ratio and phase relationship of each discrete frequency component in the reference signal. The composite excitation signal is used to synchronously excite the nonlinear response of the radio frequency front-end at at least one harmonic frequency point or intermodulation frequency point in the operating frequency band.

3. The method according to claim 1, characterized in that, The step of obtaining the spatial complex field distribution information of at least one nonlinear response signal generated by the radio frequency front-end excited by the composite excitation signal includes: A predefined spatial scanning scheme is executed to obtain the amplitude and phase data of the nonlinear response signal at multiple spatial sampling points. The spatial scanning scheme is used to indicate the sequence of measurement points in the near-field or far-field region of the radio frequency front-end radiation. The density of the sequence of measurement points meets the sampling requirements for spatial frequency reconstruction of the equivalent radiation source of the radio frequency front-end.

4. The method according to claim 1, characterized in that, Based on the spatial complex field distribution information and the structural information of the radio frequency front-end, the propagation path of the nonlinear response signal from the generation source point inside the radio frequency front-end to the radiation point is determined, including: Based on the structural information of the radio frequency front end, an electromagnetic simulation model with known circuit connection relationships is constructed; Using the spatial complex field distribution information as the field constraint condition of the electromagnetic simulation model on the radiation boundary, the virtual source distribution information that generates the equivalent radiation field inside the radio frequency front end is determined by solving the electromagnetic simulation model. Based on the virtual source distribution information and the circuit connection relationship, the propagation path of the nonlinear response signal from the generation source point inside the radio frequency front end to the radiation point is determined.

5. The method according to claim 1, characterized in that, The step of locating at least one target circuit node inside the radio frequency front end according to the propagation path includes: Based on the propagation path, a signal transmission link is determined, and the signal transmission link sequentially indicates each node through which the nonlinear response signal passes in the order of signal transmission; Extract the spatial complex field distribution features corresponding to the main frequency components of the nonlinear response signal, wherein the spatial complex field distribution features include the amplitude and phase variation features of the nonlinear response signal; The spatial complex field distribution features are matched with a pre-stored feature library. One or more candidate circuit nodes with a matching degree higher than a preset matching threshold are selected from the feature library. The feature library stores theoretical spatial field distribution features of various typical nonlinear circuit nodes when they fail. The candidate circuit node located in the signal transmission link is determined as the target circuit node.

6. The method according to claim 1, characterized in that, Determining the type of nonlinear distortion caused by the target circuit node includes: Separate the signal component corresponding to the target circuit node from the spatial complex field distribution information; If the dominant frequency component of the signal component is an integer multiple of a single frequency component in the composite excitation signal, then the nonlinear distortion type is determined to be a harmonic distortion type. If the dominant frequency component of the signal component is the sum, difference, or combination of two or more frequency components in the composite excitation signal, then the nonlinear distortion type is determined to be an intermodulation distortion type.

7. The method according to claim 1, characterized in that, Before acquiring the spatial complex field distribution information, the method further includes: The composite excitation signal is used to excite a preset calibration piece; The spatial complex field distribution information of the nonlinear response signal generated by the calibration component is obtained as reference data. The spatial complex field distribution information excited by the composite excitation signal in the radio frequency front end is compared with the reference data to eliminate nonlinear background noise and channel response error.

8. The method according to claim 1, characterized in that, Also includes: Based on the test results, the configuration of the composite excitation signal is adjusted to generate a second excitation signal; The second excitation signal is used to continuously excite the radio frequency front end to obtain the verification result; By comparing the verification results with the test results, it is determined whether the positional deviation of the same target circuit node exceeds a preset threshold. If the positional deviation does not exceed the preset threshold, the test result is determined to be valid. If the positional deviation exceeds the preset threshold, the test result is marked as pending to initiate a new round of diagnostic procedures.

9. A radio frequency performance testing device, characterized in that, include: The data acquisition module is used to acquire the structural information of the RF front-end under test; A signal construction module is used to construct a composite excitation signal, which is used to excite the radio frequency front end; The excitation response module is used to acquire the spatial complex field distribution information of at least one nonlinear response signal generated by the radio frequency front-end excited by the composite excitation signal, and, in combination with the structural information of the radio frequency front-end, determine the propagation path of the nonlinear response signal from the generation source point inside the radio frequency front-end to the radiation point. A node localization module is used to locate at least one target circuit node inside the radio frequency front end, and simultaneously determine the type of nonlinear distortion caused by the target circuit node. The test output module is used to determine and output test results based on the target circuit node and the type of nonlinear distortion.

10. An electronic device, characterized in that, The device includes a memory and a processor, the memory being connected to the processor, the processor being configured to execute one or more computer programs stored in the memory, the processor causing the electronic device to implement the radio frequency performance testing method as described in any one of claims 1-8 when executing the one or more computer programs.

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