WO2014089733A1

WO2014089733A1 - Multipath fading simulation method and multipath fading simulation device

Info

Publication number: WO2014089733A1
Application number: PCT/CN2012/086262
Authority: WO
Inventors: 刘之勇; 王俊
Original assignee: 华为技术有限公司
Priority date: 2012-12-10
Filing date: 2012-12-10
Publication date: 2014-06-19
Also published as: CN103222210A; CN103222210B

Abstract

The present invention relates to the field of network communications, and in particular, disclosed is a multipath fading simulation method, comprising: receiving input signals; according to a calibration control voltage, controlling a power fading amount, and fading the input signals to obtain faded signals; subtracting the power of the faded signals from the power of the input signals to obtain an actual power fading amount; and according to a target power fading amount and the actual power fading amount, determining the calibration control voltage.

Description

Multipath fading simulation method and multipath fading simulation device

The present invention relates to network communication technologies, and in particular, to a multipath fading simulation method and a multipath fading simulation device. Background technique

The microwave equipment belongs to the wireless communication system. During the process of atmospheric space propagation, the microwave signal is affected by many factors such as atmospheric pressure, temperature, humidity, and propagation topography, and the microwave signal passes through multiple paths to the receiving end. These multipath signals are carried out. After the vector synthesis, the intensity of the microwave signal is attenuated, resulting in multipath fading. The most intuitive reflection is that the RSL (Received Signal Level) appears to fluctuate rapidly. When multipath fading occurs, RSL changes quickly, has a short duration, and is concentrated in a period of time. Severe multipath fading can cause errors and even service interruptions in microwave equipment, which seriously affects normal microwave communication.

The multi-path fading resistance of microwave equipment is an important indicator to measure its performance. It is a necessary test for equipment suppliers to verify the microwave products in the laboratory and the operators to conduct microwave equipment network certification tests. Therefore, the accuracy of multipath fading simulation directly affects the objective judgment of equipment suppliers and operators on the multipath fading resistance of equipment.

In order to simulate multipath fading in a laboratory environment, it is necessary to demonstrate the process of rapid RSL fluctuations. In the prior art, a manual continuously adjustable attenuator is added between the transceivers of the microwave device, and the attenuation and decay time of the attenuator are controllable. However, this method requires manual adjustment of the attenuation of the attenuator, and the control accuracy cannot be guaranteed. Summary of the invention

The embodiment of the invention provides a multipath fading simulation method and a multipath fading simulation device, which solves the problem that the prior art manually adjusts the attenuation amount and cannot guarantee the control precision. Embodiments of the present invention use the following technical solutions:

A first aspect of the present invention provides a multipath fading simulation method, including:

Receiving an input signal; controlling a power attenuation amount according to the calibration control voltage, attenuating the input signal to obtain an attenuation signal;

The power of the input signal is subtracted from the power of the attenuation signal to obtain an actual power attenuation amount; and the calibration control voltage is determined according to the target power attenuation amount and the actual power attenuation amount. In a first possible implementation, the determining the calibration control voltage according to the target power attenuation amount and the actual power attenuation amount, specifically includes:

Attenuating the input signal with a voltage controlled attenuator;

Determining, according to the actual attenuation curve of the voltage control attenuator, an actual control voltage corresponding to the actual power attenuation amount; determining, according to the ideal attenuation curve of the voltage control attenuator, a target control voltage corresponding to the target power attenuation amount;

The calibration control voltage is obtained by subtracting the actual control voltage from the target control voltage and adding the target control voltage.

With reference to the first possible implementation of the first aspect, in a second possible implementation, the method further includes:

Receiving a test signal; controlling the amount of power attenuation according to the test voltage, attenuating the test signal to obtain a test attenuation signal;

Subtracting the power of the test signal by the power of the test attenuation signal to obtain a test power attenuation amount;

Adjusting the test voltage according to a voltage variation range in a stepwise manner; determining an actual attenuation curve of the voltage control attenuator according to a correspondence between the test voltage and the test power attenuation amount.

In conjunction with the second possible implementation of the first aspect, in a third possible implementation, the test signal is the input signal.

With reference to the first possible implementation of the first aspect, the second possible implementation of the first aspect, or the third possible implementation of the first aspect, in a fourth possible implementation manner, The method also includes:

Forming a curve segment for each adjacent two points in the actual attenuation curve of the voltage control attenuator, taking a plurality of continuous curve segments having the same slope as an interval, and selecting a region having the largest slope as a linear interval, according to the linear interval The first and last two points determine the ideal attenuation curve of the voltage controlled attenuator.

A first aspect of the present invention provides a multipath fading simulation apparatus including a voltage controlled attenuator, a calibration fitting unit, and a coupling unit:

The voltage control attenuator is configured to receive an input signal; control a power attenuation amount according to a calibration control voltage output by the calibration fitting unit, attenuate the input signal, and output an attenuation signal; Receiving an attenuation signal from the coupling unit; subtracting the power of the attenuation signal from the power of the attenuation signal to obtain an actual power attenuation amount; determining the calibration control voltage according to the target power attenuation amount and the actual power attenuation amount; Outputting the calibration control voltage to the voltage control attenuator;

The coupling unit is configured to receive the attenuation signal from the voltage control attenuator; output the attenuation signal to the calibration fitting unit; and output the attenuation signal as an output signal.

In a first possible implementation manner, the calibration and fitting unit is configured to include:

a processing unit, configured to receive an attenuation signal from the coupling unit; subtracting a power of the attenuation signal from a power of the input signal to obtain an actual power attenuation amount;

a control unit, configured to determine an actual control voltage corresponding to the actual power attenuation amount according to the actual attenuation curve of the voltage control attenuator; and determine, according to the ideal attenuation curve of the voltage control attenuator, the target power attenuation amount Target control voltage;

And a calibration unit, configured to subtract the actual control voltage from the target control voltage and the target control voltage to obtain the calibration control voltage; and output the calibration control voltage to the voltage control attenuator.

In conjunction with the first possible implementation of the first aspect, in a second possible implementation, the apparatus further includes: The voltage control attenuator is further configured to receive a test signal; control a power attenuation amount according to a test voltage output by the calibration fitting unit, attenuate the test signal, and output a test attenuation signal;

The coupling unit is further configured to receive the test attenuation signal from the voltage control attenuator, and output the test attenuation signal to the calibration fitting unit;

The calibration fitting unit further includes:

The processing unit is further configured to receive the test attenuation signal from the coupling unit, and subtract a power of the test attenuation signal from a power of the test signal to obtain a test power attenuation amount;

The calibration unit is further configured to output the test voltage according to a voltage variation range in a stepwise manner;

The control unit is further configured to determine an actual attenuation curve of the voltage controlled attenuator according to a correspondence between the test voltage and the test power attenuation amount.

In conjunction with the second possible implementation of the first aspect, in a third possible implementation, the test signal is an input signal.

With reference to the first possible implementation of the first aspect, the second possible implementation of the first aspect, or the third possible implementation of the first aspect, in a fourth possible implementation, the control The unit is further configured to form a curve segment for each adjacent two points in the actual attenuation curve of the voltage control attenuator, and use a plurality of continuous curve segments having the same slope as an interval, and select the interval with the largest slope as the linear interval. An ideal attenuation curve of the voltage controlled attenuator is determined based on the first and last two points of the linear interval.

The multipath fading simulation method and the multipath fading simulation device provided by the embodiments of the present invention use a negative feedback calibration and a predistortion fitting method to implement a negative feedback calibration and a predistortion fitting on the attenuated signal. The automatic simulation of path fading is simple to implement and high in control precision. DRAWINGS

In order to more clearly illustrate the technical solution of the embodiment of the present invention, the following needs in the embodiment. BRIEF DESCRIPTION OF THE DRAWINGS The drawings used in the following description are merely illustrative of the embodiments of the present invention, and those of ordinary skill in the art may The drawings obtain other figures.

1 is a flowchart of a multipath fading simulation method according to an embodiment of the present invention; FIG. 2 is a structural block diagram of a multipath fading simulation device according to an embodiment of the present invention; A block diagram of another multipath fading simulation device provided. detailed description

Embodiments of the present invention provide a multipath fading simulation method and a multipath fading simulation device. In order to better understand the technical solutions of the present invention, the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

It should be understood that the described embodiments are only a part of the embodiments of the invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

An embodiment of the present invention provides a multipath fading simulation method, and the process thereof is as shown in FIG. 1. The method specifically includes the following steps:

Step S110, receiving an input signal; controlling the power attenuation amount according to the calibration control voltage, and attenuating the input signal to obtain an attenuation signal.

In this embodiment, the input signal may be an RF (Radio Frequency) signal.

The power attenuation is controlled according to the calibration control voltage, and the input signal is attenuated to obtain an attenuation signal. This power variation relationship between the input signal and the attenuated signal simulates the multipath fading process. However, in order to accurately control multipath fading, further fitting processing is required.

Step S120, subtracting the power of the attenuation signal from the power of the input signal to obtain the actual power attenuation.

Step S130, determining a calibration control voltage according to the target power attenuation amount and the actual power attenuation amount. In this embodiment, the target power attenuation amount can be pre-configured. Further, in step S130, determining the calibration control voltage according to the target power attenuation amount and the actual power attenuation amount may specifically include:

Step S131, using an voltage control attenuator to attenuate the input signal; determining an actual control voltage corresponding to the actual power attenuation amount according to the actual attenuation curve of the voltage controlled attenuator; determining the target power attenuation amount according to the ideal attenuation curve of the voltage controlled attenuator Corresponding target control voltage; Step S132, subtracting the actual control voltage from the target control voltage and adding the target control voltage to obtain a calibration control voltage.

In this embodiment, the actual attenuation curve of the voltage controlled attenuator, that is, the actual attenuation characteristic of the voltage controlled attenuator, is the actual corresponding relationship between the control voltage and the power attenuation amount of the voltage controlled attenuator at each operating frequency, that is, one horizontal axis is The control voltage, the vertical axis is a two-dimensional curve of the amount of power attenuation.

The ideal attenuation curve of the voltage controlled attenuator, that is, the ideal attenuation characteristic of the voltage controlled attenuator, is a linear correspondence between the control voltage and the power attenuation of the voltage controlled attenuator at each operating frequency.

The actual attenuation curve and the ideal attenuation curve can be pre-configured or obtained by automatic traversal before testing for subsequent fitting processing.

Due to the performance difference of the voltage-controlled attenuator itself, the actual attenuation curve of the voltage-controlled attenuator has linear distortion. To ensure accurate linear multipath fading of the device of the present invention, pre-distortion fitting of the control voltage is required to ensure the target power of the output. Amount of attenuation.

The target control voltage is subtracted from the actual control voltage plus the target control voltage to obtain the calibration control voltage, ie the calibration control voltage is K + - 13⁄4. Where, it represents the target control voltage and represents the actual control voltage.

Considering that the operating frequency range (6 GHz to 42 GHz) of microwave equipment is very wide, the attenuation curves of voltage-controlled attenuators at different operating frequencies are different. Therefore, the ideal attenuation curve and the actual attenuation curve of the voltage controlled attenuator are required before calibration.

In another embodiment, a multipath fading simulation method is provided. Based on the steps S110 to S130 of the multipath fading simulation method, the method may further include:

Step S140, receiving a test signal; controlling the power attenuation amount according to the test voltage, and testing the signal Attenuation is performed to obtain a test attenuation signal;

Step S150, subtracting the power of the test signal from the power of the test attenuation signal to obtain a test power attenuation amount;

Step S160, adjusting the test voltage according to the voltage variation range in a stepwise manner; determining the actual attenuation curve of the voltage control attenuator according to the corresponding relationship between the test voltage and the test power attenuation amount.

In this embodiment, the input signal may be used as the test signal, or other signals may be used as the test signal.

The step value and voltage variation range can be set in advance, for example, in steps of 0.1V, and the voltage variation range is -5V~0V.

The test signal can obtain the actual attenuation characteristics at each operating frequency of the voltage controlled attenuator at different operating frequencies.

Further, the method may further include:

Step S170, forming a curve segment for each adjacent two points in the actual attenuation curve of the voltage control attenuator, taking a plurality of continuous curve segments having the same slope as an interval, and selecting the interval with the largest slope as the linear interval, according to the linear interval The first and last two points determine the ideal attenuation curve of the voltage controlled attenuator.

In this embodiment, the ideal attenuation curve can be determined according to the first and last two points of the linear interval:

a(v) = ^A " ~ ^A ° (v - V ) + A ( 1 ) where V is the control voltage variable, "representing the attenuation value variable, ! is the function of ", with ( indicating; indicating the starting point of the linear interval The control voltage, I ^ represents the control voltage at the end of the linear interval, Α ₀ represents the attenuation of the start of the linear interval, and ^ represents the attenuation of the end of the linear interval.

A multipath fading simulation method provided by an embodiment of the present invention uses a negative feedback calibration and a predistortion fitting method to implement automatic simulation of multipath fading by performing negative feedback calibration and predistortion fitting on the attenuated signal. Simple implementation and high control precision. The embodiment of the present invention provides a multipath fading simulation device, which has the structure shown in FIG. 2, and includes: a voltage control attenuator 210, configured to receive an input signal, and control power attenuation according to a calibration control voltage output by the calibration fitting unit 220. Quantity, attenuates the input signal and outputs an attenuation signal.

In this embodiment, the input signal may be an RF (Radio Frequency) signal.

A voltage control attenuator can be realized by using a FET (Field Effect Transistor) circuit, a PIN (ositive-intrinsicnegative) diode, a GaAs MESFET (Metal-Semiconductor FET), or the like. For example, microwave equipment has a higher operating frequency, generally 6 GHz to 42 GHz. Therefore, a FET circuit can be used to implement a voltage controlled attenuator. The internal DC voltage control signals of VI and V2 are used to change the voltage of VI and V2. To control the on-off condition of the internal FET to change the amount of attenuation. In order to increase the attenuation dynamic range of the voltage controlled attenuator, the voltage control ports of VI and V2 can be connected and controlled by the same variable voltage source to increase the attenuation dynamic range.

Changing the voltage control attenuator's control voltage, the voltage-controlled attenuator produces a power attenuation corresponding to the control voltage.

In the present embodiment, the calibration control voltage is used as the control voltage of the voltage control attenuator 210 to attenuate the input signal through the voltage control attenuator 210, and outputs an attenuation signal. Finally, this power variation relationship between the input signal and the attenuated signal simulates the process of multipath fading. However, in order to accurately control multipath fading, further fitting processing is required.

a calibration fitting unit 220, configured to receive an attenuation signal from the coupling unit 230, subtract the power of the attenuation signal from the power of the input signal, to obtain an actual power attenuation amount; and determine a calibration control voltage according to the target power attenuation amount and the actual power attenuation amount; The calibration control voltage is output to the voltage controlled attenuator 210.

In this embodiment, the target power attenuation amount can be pre-configured.

The power of the input signal can be pre-configured; the calibration fitting unit 220 can also receive the input signal and obtain the amount of power attenuation of the input signal based on the input signal and the attenuation signal.

The coupling unit 230 is configured to receive the attenuation signal from the voltage control attenuator 210, output the attenuation signal to the calibration fitting unit 220, and output the attenuation signal as an output signal. Further, the calibration fitting unit 220 may specifically include a processing unit 221, a calibration unit 222, and a control unit 223, as shown in FIG. 3:

The processing unit 221 is configured to receive the attenuation signal from the coupling unit 230, and subtract the power of the attenuation signal from the power of the input signal to obtain an actual power attenuation amount.

The control unit 223 is configured to determine an actual control voltage corresponding to the actual power attenuation amount according to the actual attenuation curve of the voltage control attenuator 210; and determine the target power attenuation amount according to the ideal attenuation curve of the voltage control attenuator 210. Target control voltage.

In this embodiment, the actual attenuation curve of the voltage control attenuator 210, that is, the actual attenuation characteristic of the voltage control attenuator 210, is the actual correspondence between the control voltage and the power attenuation amount of the voltage control attenuator 210 at each operating frequency, that is, one The horizontal axis is the control voltage and the vertical axis is the two-dimensional curve of the power attenuation.

The ideal attenuation curve of the voltage controlled attenuator 210, i.e., the ideal attenuation characteristic of the voltage controlled attenuator 210, is the linear correspondence between the control voltage and the amount of power attenuation at each operating frequency of the voltage controlled attenuator 210.

The actual attenuation curve and the ideal attenuation curve can be pre-configured or obtained by automatic traversal before testing according to the actual operating frequency of the device under test, for subsequent fitting processing.

The calibration unit 222 is configured to subtract the actual control voltage from the target control voltage and the target control voltage to obtain a calibration control voltage; and output a calibration control voltage to the voltage control attenuator 210.

Due to the performance difference of the voltage controlled attenuator itself, the actual attenuation curve of the voltage controlled attenuator has linear distortion. In order to ensure the linear multipath fading of the absolute uniform rate of the device of the present invention, the predistortion fitting of the control voltage is required to ensure the output. Target power attenuation.

The target control voltage is subtracted from the actual control voltage plus the target control voltage to obtain the calibration control voltage, ie the calibration control voltage is K + - 13⁄4. Where, it represents the target control voltage and represents the actual control voltage. Considering the wide operating frequency range (6GHz~42GHz) of microwave equipment, voltage control attenuator The attenuation curves at different operating frequencies are different. Therefore, the ideal attenuation curve and the actual attenuation curve of the voltage controlled attenuator are required before calibration.

In another embodiment, a multipath fading simulation apparatus is provided. Based on the voltage control attenuator 210, the calibration fitting unit 220, and the coupling unit 230 of the multipath fading simulation apparatus, the apparatus may further include:

The voltage control attenuator 210 is further configured to receive the test signal; control the power attenuation amount according to the test voltage output by the calibration fitting unit 220, attenuate the test signal, and output a test attenuation signal; and the coupling unit 230 is further configured to control the attenuation from the voltage. The device 210 receives the test attenuation signal, and outputs the test attenuation signal to the calibration fitting unit 220;

The calibration fitting unit 220 further includes:

The processing unit 221 is further configured to receive the test attenuation signal from the coupling unit 230; subtract the power of the test signal from the power of the test signal to obtain a test power attenuation amount;

The calibration unit 222 is further configured to output the test voltage according to the voltage variation range in a stepwise manner; the control unit 223 is further configured to obtain the actual attenuation of the voltage control attenuator 210 according to the correspondence between the rate test voltage and the test power attenuation amount. curve.

In this embodiment, the step value and the voltage variation range may be preset, for example, a step value of 0. IV, and a voltage variation range of -5V to 0V.

The test signal can be an input signal or not.

The test signal can obtain the actual attenuation characteristics at various operating frequencies of the voltage controlled attenuator 210 at different operating frequencies, and the attenuation characteristics can be formed into a three-dimensional matrix in the manner shown in Table 1.

Table 1

Fn Vn An In the practical application, in order to facilitate storage of large-capacity data and facilitate data reuse, the actual attenuation characteristics of the voltage control attenuator 210 can also be stored in the control unit or an external E connected to the control unit. ² Storage media such as PROM.

Further, the control unit 223 can also be configured to form a curve segment for each adjacent two points in the actual attenuation curve of the voltage control attenuator 210, and use a plurality of continuous curve segments having the same slope as an interval, and select the maximum slope. The interval is taken as a linear interval, and the ideal attenuation curve of the voltage controlled attenuator 210 is determined according to the first and last points of the linear interval.

Where V is the control voltage variable, "representing the attenuation value variable, > is a function of ", using ("; represents the control voltage at the beginning of the linear interval, I ^ represents the control voltage at the end of the linear interval, Α ₀ represents the starting point of the linear interval The amount of attenuation, ^ represents the amount of attenuation at the end of the linear interval.

According to the characteristics of the voltage controlled attenuator, the larger the slope, the better the output characteristics, so the maximum slope is chosen as the slope of the ideal attenuation curve of the voltage controlled attenuator. Another embodiment of the present invention provides a multipath fading simulation device, which has the structure shown in FIG. 4, and includes:

The voltage control attenuator 410 is configured to receive an input signal; control a power attenuation amount according to a calibration control voltage output by the processor 430, attenuate the input signal, and output an attenuation signal.

a memory 420, configured to store information including a program routine;

The processor 430 is coupled to the memory 420, the voltage control attenuator 410, and the coupling unit 440 for controlling the execution of the program routine, and specifically includes: receiving the attenuation signal from the coupling unit 440; and subtracting the power of the input signal from the power of the attenuation signal. , obtaining the actual power attenuation amount; determining the calibration control voltage according to the target power attenuation amount and the actual power attenuation amount; outputting the calibration control voltage to the voltage control Attenuator 410;

The coupling unit 440 is configured to receive the attenuation signal from the voltage control attenuator 410; output the attenuation signal to the processor 430; and output the attenuation signal as an output signal.

Further, in the processor 430, determining the calibration control voltage according to the target power attenuation amount and the actual power attenuation amount may specifically include:

According to the actual attenuation curve of the voltage control attenuator 410, the actual control voltage corresponding to the actual power attenuation amount is determined; according to the ideal attenuation curve of the voltage control attenuator 410, the target control voltage corresponding to the target power attenuation amount is determined;

The target control voltage is subtracted from the actual control voltage plus the target control voltage to obtain the calibration control voltage.

Further, the device may further include:

The voltage control attenuator 410 is further configured to receive the test signal; control the power attenuation according to the test voltage output by the processor 430, attenuate the test signal, and output a test attenuation signal;

The processor 430 may further include: receiving a test attenuation signal from the coupling unit 440; subtracting the power of the test signal from the power of the test attenuation signal to obtain a test power attenuation amount; and outputting the test voltage according to the voltage variation range in a stepwise manner; Determining the actual attenuation curve of the voltage controlled attenuator according to the correspondence between the test voltage and the test power attenuation amount;

The coupling unit 440 is further configured to receive a test attenuation signal from the voltage control attenuator 410, and output the test attenuation signal to the processor 430;

Further, the processor 430 may further include: forming a curve segment for each adjacent two points in the actual attenuation curve of the voltage control attenuator, and using a plurality of continuous curve segments having the same slope as an interval, and selecting the interval with the largest slope As a linear interval, the ideal attenuation curve of the voltage controlled attenuator is determined based on the first and last points of the linear interval.

The above embodiment is a multipath fading simulation device, and the information exchange, execution process, and the like between the internal units are based on the same concept as the method embodiment of the present invention. For details, refer to the description in the method embodiment of the present invention. I will not repeat them here. A multipath fading simulation device provided by an embodiment of the present invention uses a negative feedback calibration and a predistortion fitting method to implement automatic simulation of multipath fading by performing negative feedback calibration and predistortion fitting on the attenuated signal. Simple implementation and high control precision. A person skilled in the art can understand that all or part of the steps of the foregoing embodiment can be implemented by a computer program to instruct related hardware, and the program can be stored in a computer readable storage medium. In execution, the flow of an embodiment of the methods as described above may be included. The storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM).

The above is only the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any change or replacement that can be easily conceived by those skilled in the art within the technical scope of the present invention is All should be covered by the scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

claims

1. A multipath fading simulation method, characterized by including:

Receive an input signal; control the power attenuation amount according to the calibration control voltage, attenuate the input signal to obtain an attenuated signal;

Subtract the power of the attenuated signal from the power of the input signal to obtain the actual power attenuation; determine the calibration control voltage according to the target power attenuation and the actual power attenuation.

2. The multipath fading simulation method according to claim 1, characterized in that, determining the calibration control voltage according to the target power attenuation amount and the actual power attenuation amount specifically includes:

Attenuating the input signal using a voltage controlled attenuator;

Determine the actual control voltage corresponding to the actual power attenuation amount according to the actual attenuation curve of the voltage control attenuator; determine the target control voltage corresponding to the target power attenuation amount according to the ideal attenuation curve of the voltage control attenuator;

The calibrated control voltage is obtained by subtracting the actual control voltage from the target control voltage and adding the target control voltage.

3. The multipath fading simulation method according to claim 2, characterized in that the method further includes:

Receive a test signal; control the power attenuation amount according to the test voltage, attenuate the test signal to obtain a test attenuation signal;

Subtract the power of the test attenuation signal from the power of the test signal to obtain the test power attenuation amount;

The test voltage is adjusted in a stepwise manner according to the voltage change range; and the actual attenuation curve of the voltage control attenuator is determined according to the corresponding relationship between the test voltage and the test power attenuation amount.

4. The multipath fading simulation method according to claim 3, characterized in that the test signal is the input signal.

5. The multipath fading simulation method according to claim 2, 3 or 4, characterized in that the method further includes: Each two adjacent points in the actual attenuation curve of the voltage-controlled attenuator form a curve segment, multiple continuous curve segments with the same slope are used as an interval, and the interval with the largest slope is selected as the linear interval. According to the linear interval The first and last two points determine the ideal attenuation curve of the voltage-controlled attenuator.

6. A multipath fading simulation device, characterized by including a voltage-controlled attenuator, a calibration fitting unit and a coupling unit:

The voltage control attenuator is used to receive an input signal; control the power attenuation amount according to the calibration control voltage output by the calibration fitting unit, attenuate the input signal and output an attenuated signal; the calibration fitting unit is used For receiving the attenuated signal from the coupling unit; subtracting the power of the attenuated signal from the power of the input signal to obtain the actual power attenuation; determining the calibration control voltage according to the target power attenuation and the actual power attenuation; outputting the calibration control voltage to the voltage controlled attenuator;

The coupling unit is configured to receive the attenuation signal from the voltage-controlled attenuator; output the attenuation signal to the calibration fitting unit; and output the attenuation signal as an output signal.

7. The multipath fading simulation device according to claim 6, characterized in that the calibration fitting unit includes:

A processing unit, configured to receive an attenuated signal from the coupling unit; subtract the power of the attenuated signal from the power of the input signal to obtain the actual power attenuation amount;

A control unit, configured to determine the actual control voltage corresponding to the actual power attenuation amount according to the actual attenuation curve of the voltage control attenuator; determine the corresponding target power attenuation amount according to the ideal attenuation curve of the voltage control attenuator. target control voltage;

A calibration unit, used to subtract the actual control voltage from the target control voltage and add the target control voltage to obtain the calibration control voltage; output the calibration control voltage to the voltage control attenuator.

8. The multipath fading simulation device according to claim 7, characterized in that the device further includes:

The voltage control attenuator is also used to receive test signals; output according to the calibration fitting unit The test voltage controls the power attenuation amount, attenuates the test signal, and outputs the test attenuation signal; the coupling unit is also used to receive the test attenuation signal from the voltage control attenuator, and output the test attenuation signal. to the calibration fitting unit;

The calibration fitting unit also includes:

The processing unit is also configured to receive the test attenuation signal from the coupling unit; subtract the power of the test attenuation signal from the power of the test signal to obtain the test power attenuation amount;

The calibration unit is also configured to output the test voltage according to the voltage variation range in a stepwise manner; the control unit is further configured to determine the test voltage according to the corresponding relationship between the test voltage and the test power attenuation amount. The actual attenuation curve of the voltage controlled attenuator.

9. The multipath fading simulation device according to claim 8, wherein the test signal is an input signal.

10. The multipath fading simulation device according to claim 7, 8 or 9, characterized in that the control unit is also used to form every two adjacent points in the actual attenuation curve of the voltage control attenuator into one For the curve segment, multiple continuous curve segments with the same slope are taken as an interval, the interval with the largest slope is selected as the linear interval, and the ideal attenuation curve of the voltage-controlled attenuator is determined based on the first and last points of the linear interval.