CN-121981043-A - Modeling method of radio frequency system behavior model based on data flow driving

CN121981043ACN 121981043 ACN121981043 ACN 121981043ACN-121981043-A

Abstract

The invention discloses a modeling method of a radio frequency system behavior model based on data flow driving, which comprises the steps of carrying out preprocessing based on IQ modulation on a complex input signal to reduce the sampling frequency of the input signal, facilitating processing, summarizing various physical characteristics related to a radio frequency system according to engineering practice, utilizing mathematical expressions to represent the action modes of the physical characteristics on the input signal based on a physical characteristic action mechanism, constructing a characteristic model, cascading the physical characteristic models according to the engineering practice, combining the physical characteristic models to form a system-level model oriented to a specific type of system, importing measured parameters, preprocessing the measured parameters, and enabling the measured parameters to be matched with the input signal. The invention is suitable for radio frequency system level simulation verification, the behavior model constructed based on the invention can perform simulation verification on a complex system very efficiently on the premise of ensuring simulation precision, the driving mode of data flow driving can be flexibly integrated into a larger radio frequency system or a complex electronic system, the system has very good cross-platform and cross-domain integration capability, and the system working condition under a real complex signal environment can be verified in a high-reduction manner by performing data flow driving simulation on complex input signals which cannot be represented by formulas.

Inventors

LIU JUN
KE YUFENG
LI ZHIPING

Assignees

杭州电子科技大学

Dates

Publication Date: 20260505
Application Date: 20251208

Claims (6)

1. The modeling method for the radio frequency system behavior model based on data flow driving is characterized by comprising the following steps of: firstly, preprocessing an input signal based on IQ modulation; dividing the physical characteristics of the radio frequency system into noise characteristics, frequency shift characteristics, phase shift characteristics, frequency response characteristics, nonlinear characteristics and coupling characteristics; step three, utilizing mathematical expression to represent the action mode of each physical characteristic on the input signal, and constructing a characteristic model; cascading the physical characteristic models to form a system-level model oriented to a specific type of system; and fifthly, importing measured parameters, and preprocessing the measured parameters to enable the measured parameters to be matched with input signals.
2. The modeling method of a behavior model of a radio frequency system based on data stream driving as claimed in claim 1, wherein in the first step, the preprocessing of the input signal comprises: The original signal is rewritten into the following form: s (n) represents an input radio frequency signal sequence, fc represents the carrier frequency of an original radio frequency signal, the input signal of the model is two paths of signals of I (n) and Q (n), Is the carrier signal of s (n).
3. The modeling method of a behavior model of a radio frequency system based on data stream driving as claimed in claim 1, wherein the third step comprises: the noise characteristics are characterized by the following formula: Wherein, N add is the additional noise power, N in is the input noise power, P in is the average power of the input signal, NF is the system noise coefficient, SNR is the signal-to-noise ratio of the input signal, and G is the system gain curve; Representing the power of a noise source, reversely pushing a noise sequence N i (N) by utilizing Gaussian white noise characteristics, utilizing a frequency response characteristic model, taking G (NF-1) as a frequency response curve, taking the noise sequence N i (N) as an input sequence, and obtaining an additional noise sequence N add (N) by utilizing the frequency response characteristic model; the frequency shift characteristic is characterized by the following formula: t is the discrete sequence starting from 0, the length is the length of the input signal, the steps are sampling period, s (t) is the processed input baseband signal, S (t)' is the conjugate of s (t), f c is the complex carrier frequency, f i is the center frequency of the target frequency band, a is the mirror coefficient, the value is only 1 or-1, when the value is 1, the parallel movement is represented, when the value is-1, the mirror movement is represented, b is the movement distance; the phase shift characteristic is characterized by the following formula: y(n)=a k ·x(n)·e jφ kl k. i represents an attenuation control code and a phase shift control code respectively, a k 、φ kl represents an attenuation amount and a phase shift amount which are retrieved from a lookup table respectively, x (n) is an input baseband sequence, and y (n) is an output baseband sequence; the frequency response characteristic is characterized by the following formula: Y(n)=IFFT[X(f)·H(f)] Wherein X (f) is a discrete frequency spectrum of the input sequence, H (f) is a fitted S parameter curve, and Y (n) is an output sequence with superimposed frequency response characteristics; The nonlinear characteristic is characterized by the following formula: Y_nonlinear(t)＝Re[s 0 (t)+s 1 (t)e jωt +s 2 (t)e j2ωt +s 3 (t)e j3ωt ] wherein: The expression of the coefficient a 0 、a 1 、a 2 、a 3 is as follows: a 0 =0 wherein s 0 (t)、s 1 (t)、s 2 (t)、s 3 (t) is a component of the signal in a baseband frequency band, a frequency band with w as a center, a frequency band with 2w as a center and a frequency band with 3w as a center respectively, re represents a real part taking complex numbers, ωt is a phase of a carrier signal, G is a system gain curve, OIP2 (V) is a second-order intermodulation cut-off point, OIP3 (V) is a third-order intermodulation cut-off point, ω is a signal frequency, ωc is a carrier frequency and ωs is a sampling frequency; the constraint relationship is included as follows: Or alternatively When the condition (1) is satisfied, the output signal y_non linear (t) contains only the first order carrier component, that is: Y_nonlinear(t)=s 1 (t) when condition (2) is satisfied, the output signal y_non linear (t) contains DC, first, second, third order carrier components, namely: Y_nonlinear(t)=s 0 (t)+s 1 (t)+s 2 (t)+s 3 (t)。
4. The modeling method of a behavior model of a radio frequency system based on data stream driving as claimed in claim 1, wherein the fourth step comprises: And cascading the characteristic models according to the characteristic action mechanism to obtain a system model.
5. The method for modeling a behavior model of a radio frequency system based on data stream driving as claimed in claim 1, wherein the fourth step comprises cascading one or more of a noise characteristic model, a frequency response characteristic model, a frequency shift characteristic model, a phase shift characteristic model, a nonlinear characteristic model and a coupling characteristic model to obtain the system model.
6. The modeling method of a behavior model of a radio frequency system based on data stream driving as claimed in claim 1, wherein the fifth step comprises: preprocessing the measured parameters to enable the measured parameters to be matched with input signals; for noise coefficients less affected by frequency, 1dB gain compression points, second-order intermodulation points, third-order intermodulation points, etc., taking the sequence average value; The method comprises the steps of obtaining a branch line expression by connecting two adjacent points with a characteristic by using a straight line, carrying out the operation on any two adjacent points, finally constructing a piecewise function for segmenting the frequency, obtaining a piecewise function value under a corresponding frequency point according to the carrier frequency and the sampling frequency of an input signal, integrating the piecewise function value into a sequence, and taking the sequence as an actual measurement parameter sequence; finally, the method can be realized by inputting any sampling signal after the actually measured parameters are imported into the model, and outputting corresponding output signal sampling points through system action by the model.

Description

Modeling method of radio frequency system behavior model based on data flow driving Technical Field The invention belongs to the technical field of radio frequency system modeling and simulation, and relates to a radio frequency system behavior model modeling method based on data flow driving. Background Along with the continuous improvement of functions and scale of an electronic information system, the system complete machine is subjected to componentization modeling and system-level simulation verification, and the method is an important means for ensuring the design quality of the system and reducing the development cost. In the radio frequency field, a physical model is generally utilized to carry out modeling simulation in a circuit implementation design stage needing to carry out fine simulation verification. This method has a high degree of accuracy. However, when facing the system-level simulation verification requirement, this method has the following problems: 1. The simulation efficiency is low, namely the physical model is modeled by adopting a fine physical modeling method, when the system scale is large, the system complexity is high, so that the complexity of the internal structure of the model is correspondingly improved, a large amount of operation resources and operation time are consumed, and the simulation efficiency is reduced. 2. The cross-platform adaptability is poor, and the system is difficult to integrate in a large system, wherein the large electronic information system is formed by mutually coupling a plurality of subsystems. Physical models often have complex representations whose model descriptions are not uniform and are difficult to generic and migrate between different simulation tools. This makes it difficult to integrate into large systems for simulation. 3. The input signal is single, the physical level model focuses on the extraction of physical parameters, and the modeling target determines that the model does not need to have response capability to complex signal conditions, so that the input signal is single. However, this is disadvantageous for performing simulation verification at the system level. Aiming at the defect that the physical model is oriented to system-level simulation verification, the invention provides a modeling method of a radio frequency system behavior model based on data flow driving. Disclosure of Invention The invention provides a modeling method of a radio frequency system behavior model based on data flow driving in order to overcome the defects of the prior art. In order to achieve the above purpose, the present invention adopts the following technical scheme: a modeling method of a radio frequency system behavior model based on data flow driving, The method comprises the following steps: firstly, preprocessing an input signal based on IQ modulation; dividing the physical characteristics of the radio frequency system into noise characteristics, frequency shift characteristics, phase shift characteristics, frequency response characteristics, nonlinear characteristics and coupling characteristics; step three, utilizing mathematical expression to represent the action mode of each physical characteristic on the input signal, and constructing a characteristic model; cascading the physical characteristic models to form a system-level model oriented to a specific type of system; and fifthly, importing measured parameters, and preprocessing the measured parameters to enable the measured parameters to be matched with input signals. In summary, the invention has the following advantages: 1) The invention greatly improves the efficiency of simulation verification of the radio frequency system on the premise of ensuring the simulation precision, wherein the model constructed by the invention is a behavior model, and the behavior directly describes a circuit by using input/output relations (such as nonlinear polynomials, memory polynomials, volterra series and the like), omits microcosmic details of an internal transistor and greatly improves the simulation verification efficiency. The superposition of the function of the actually measured parameters is finer, the parameters are not only determined to be a certain constant value, but also the action mechanism of the parameters is truly embodied from the dimension (such as frequency) influencing the numerical transformation of the parameters, so that the simulation precision can be ensured compared with the common behavior model. 2) The invention can easily integrate the radio frequency system model into a larger electronic information system, and the model constructed by the invention is driven by data flow and shows how the output signal changes after the external signal flows through the system. The data stream is driven in such a way that it can easily form the output into other types of inputs for models that take the data stream as input. And thus can be easily integrated into a large system. 3) T