CN102938904B - A kind of standing-wave ratio detecting method, device and base station - Google Patents

Abstract

The invention discloses a kind of standing-wave ratio detecting method, device and base station, belong to moving communicating field.The method comprises determining that equivalent parameters value S of one group of antenna for base station mouth at the frequency interested of base station；Obtain the power P of the forward signal of antenna for base station mouth_FWD, the power P of reverse signal_REV, and now phase contrast between forward signal and the phase place of reverse signalAccording to described S, P_FWD、P_REVWithDetermine standing-wave ratio.Pass through the present invention, on the basis of the amplitude information of base station forward and backward signal, three different loads are utilized to calibrate out by the phase information affecting standing-wave ratio, recycling amplitude and phase information obtain the standing-wave ratio of base station, improve the precision of standing-wave ratio, thus improve the accuracy of detection antenna-feedback system connection status.

Description

Standing-wave ratio detection method, device and base station

Technical Field

The present invention relates to the field of mobile communications, and in particular, to a method and an apparatus for detecting a standing-wave ratio of a base station.

Background

A mobile communication base station needs to transmit a radio frequency signal through an antenna. However, when the antenna feeder system (feeder and antenna) is in trouble, the power of the downlink signal cannot be efficiently radiated to the space through the antenna. The base station is required to have a function of detecting whether the antenna feeder system works normally, and a common detection method is to detect a standing wave ratio of an antenna port of the base station to reflect whether the antenna feeder system works normally.

At present, the circuit structure for detecting the standing-wave ratio of a base station antenna port mainly includes the following two types: one is a circuit structure as shown in fig. 1, which indirectly obtains the forward and reverse signals of the antenna port of the base station through the coupler between the power amplifier and the duplexer; the second is a circuit structure as shown in fig. 2, which obtains the forward and reverse signals of the antenna port of the base station through the coupler near the antenna port of the base station through the duplexer.

If the base station can detect the forward and reverse signals of the antenna port of the base station, the power of the forward and reverse signals is only needed to be known when the stationary wave is calculated. However, according to the circuit structures shown in fig. 1 and fig. 2, it is difficult to directly detect the power of the forward and reverse signals at the antenna port of the base station, and there is at least a duplexer adapter between the coupler and the antenna port of the base station. The detected signal is not the signal of the antenna port of the base station, and the amplitude of the signal is only detected without using the phase information of the signal to calculate the standing-wave ratio, so that the accuracy error of the obtained standing-wave ratio is larger, and the state of the detected antenna feed system is inaccurate.

Disclosure of Invention

The invention aims to solve the technical problem of providing a method, a device and a base station which can detect the standing-wave ratio by using amplitude and phase information, and solve the problem that the detection of the state of an antenna feed system is inaccurate because the phase information is not used and the error is large when the standing-wave ratio of an antenna port of the traditional base station is detected.

In order to solve the above technical problem, according to an aspect of the present invention, the present invention provides a standing-wave ratio detection method, specifically including:

step one, determining equivalent parameter values S of a group of base station antenna ports at a frequency point of interest of a base station;

step two, acquiring the power P of the forward signal of the base station antenna port_FWDPower P of the reverse signal_REVAnd a phase difference value between phases of the forward signal and the reverse signal at this time

Step three, according to S, P_FWD、P_REVAndand determining the standing-wave ratio.

In order to solve the above technical problem, according to another aspect of the present invention, there is provided a standing-wave ratio detecting apparatus including:

the equivalent parameter acquisition module is used for acquiring equivalent parameter values S of a group of base station antenna ports at the frequency point of interest of the base station;

a power obtaining module for obtaining the power P of the forward signal of the base station antenna port_FWDAnd power P of the reverse signal_REV；

A phase difference acquisition module for determining a phase difference between phases of the forward signal and the reverse signal

A standing-wave ratio determination module for determining the standing-wave ratio according to the S, P_FWD、P_REVAndand determining the standing-wave ratio.

In order to solve the above technical problem, according to another aspect of the present invention, the present invention further provides a standing-wave ratio detecting base station, including the standing-wave ratio detecting apparatus in the above technical solution.

Compared with the prior art, the embodiment of the invention calibrates the phase information influencing the standing-wave ratio by using three different loads on the basis of the amplitude information of the forward signal and the reverse signal of the base station, and calculates the standing-wave ratio by using the amplitude and the phase information, thereby improving the accuracy of the standing-wave ratio and further improving the accuracy of detecting the connection state of the antenna feed system.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of a standing-wave ratio detection circuit in the prior art;

FIG. 2 is a schematic diagram of a standing-wave ratio detection circuit of the prior art;

FIG. 3 is a schematic diagram of an equivalent structure of a standing-wave ratio detection circuit structure of the prior art;

FIG. 4 is a schematic diagram of an equivalent parametric model of the circuit structure of FIG. 3;

fig. 5 is a flowchart of a standing-wave ratio detection method according to an embodiment of the present invention;

fig. 6 is a block diagram of a standing-wave ratio detection apparatus according to a second embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention clearer and clearer, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example one

FIG. 3 is a schematic diagram showing an equivalent structure of a standing-wave ratio detection circuit structure in the prior art; FIG. 4 is a schematic diagram of an equivalent parametric model of the circuit structure of FIG. 3; fig. 5 is a flowchart of a standing-wave ratio detection method according to an embodiment of the present invention. The method of the embodiment of the present invention is described below with reference to fig. 3, 4 and 5, and includes:

step S502, determining equivalent parameter values S of a group of base station antenna ports at the frequency point of interest of the base station;

the circuit structures shown in fig. 1 and fig. 2 can be equivalently replaced by the circuit structure shown in fig. 3, and the schematic diagram of the equivalent parameter model structure shown in fig. 4 can be obtained according to the standing-wave ratio detection circuit structure shown in fig. 3, so that accurate standing-wave ratio of the base station needs to be calculated accurately_L。

From the equivalent parametric model structure diagram of fig. 4, the relation (1) can be obtained:

${\mathrm{\Γ}}_{\mathrm{IN}}=S_{11}+\frac{S_{21}\×S_{12}\×{\mathrm{\Γ}}_L}{1-S_{22}\×{\mathrm{\Γ}}_L}---\left(1\right)$

from the relational expression (1), the relational expression (2) can be obtained

${\mathrm{\Γ}}_L=\frac{{\mathrm{\Γ}}_{\mathrm{IN}}-S_{11}}{S_{12}\×S_{21}-S_{11}\×S_{22}+{\mathrm{\Γ}}_{\mathrm{IN}}{S}_{22}}---\left(2\right)$

Wherein,_INfor the reflection coefficient seen from the left to the right of the radio frequency module,_Lfor the base station antenna port reflection coefficient, both parameters are vectors, including amplitude and phase information.

Wherein S is₁₁、S₂₂、S₁₂×S₂₁Is the equivalent parameter value S for a set of base station antenna ports, the S parameter for a network of 4 ports in fig. 4, the S parameter being defined by the ratio of two complex numbers, including amplitude and phase information. S11 is the reflection coefficient of port 1 when port 2 is matched; s22 is the reflection coefficient of port 2 when port 1 is matched; s12 is the reverse transmission coefficient from port 2 to port 1 when port 1 is matched; s21 is the forward transmission coefficient of port 1 to port 2 when port 2 is matched. It is noted that these parameters are vectors, which include not only amplitude information but also phase information about the signal, and that once the base station has settled, S₁₁、S₂₂、S₁₂×S₂₁Is fixed and unchangeable.

And according to the definition of the voltage reflection coefficient, the following formula (3) is provided:

${\mathrm{\Γ}}_{\mathrm{IN}}=\frac{V_r}{V_i}=\sqrt{\frac{P_{\mathrm{REV}}}{P_{\mathrm{FWD}}}}\∠\mathrm{\φ}---\left(3\right)$

wherein, V_iAnd V_rRespectively representing the incident and reflected voltages on the left side of the module, P_FWDFor the forward signal power value, P, at which the forward signal is coupled_REVFor the reverse signal power value at the reverse signal coupling,is the phase difference between the forward signal and the reverse signal.

Due to the existing method for solving_LFor S parameters (including S)₁₁、S₂₂、S₁₂×S₂₁) Using approximately equal and solving_INOnly the power amplitude information of the forward and backward signals is used, and no phase information is used, so that_LThe obtained standing-wave ratio of the base station has a relatively large error. Therefore, the base station is calibrated in this step using three loads with known reflection coefficients to obtain an accurate set of S parameters (including S) with phase information₁₁、S₂₂、S₁₂×S₂₁) The method specifically comprises the following steps:

connecting the base station antenna interface with a load 1 with known S parameters, wherein the reflection coefficient of the load is_L1. The base station transmits signals of interested frequency points, and two paths of analog-to-digital converters are utilized to directly acquire forward and reverse signals to obtain corresponding P_FWD1And P_REV1Then, the angle value ∠ V of the reverse signal is obtained_REV1And the angle value ∠ V of the forward signal_FWD1Is not equal toThen according to the formula (3) to obtain_IN1。

Similarly, the base station antenna interface is connected with a load 2 with known S parameters, and the reflection coefficient of the load is_L2The base station transmits the signals of the frequency points of interest to obtain the corresponding P_FWD2、P_REV2And a phase differenceThen according to the formula (3) to obtain_IN2. It should be noted that_L2Is not equal to_L1。

Similarly, the base station antenna interface is connected with a load 3 with known S parameters, and the reflection coefficient of the load is_L3. The base station transmits the signals of the frequency points of interest to obtain the corresponding P_FWD3、P_REV3And a phase differenceThen according to the formula (3) to obtain_IN3. It should be noted that_L3Is not equal to_L1Is also not equal to_L2。

In the above step, the selection of the frequency point of interest is related to the frequency band information of the base station, for example, if the RRU of this model supports the frequency band of 2110-2170MHz, then the frequency point of interest is 2110-2170MHz, so that only the S value of this frequency band needs to be determined. And the other RRU supports the 925-.

Obtained by the above three steps_IN1、_IN2、_IN3And are known_L1、_L2、_L3And the equations are respectively substituted into the formula (2) to obtain 3 equations. Three unknowns are solved using these 3 equations: s₁₁、S₂₂、S₁₂×S₂₁. Thus, the frequency of interest of the base station can be obtainedA set of equivalent parameter values S (including S) at a point₁₁、S₂₂、S₁₂×S₂₁) It is stored as a table of S information about the frequency points of interest.

Step S504, obtaining the power P of the forward signal of the base station antenna port_FWDPower P of the reverse signal_REVAnd the phase difference value of the forward signal and the reverse signal at the time

When the base station works, when the standing-wave ratio of the base station when the antenna port of the base station is connected with any load needs to be detected, the forward power PFWD and the reverse power P of the antenna port of the base station at the moment are obtained by sampling the forward signal and the reverse signal through the two analog-to-digital converters_REVThen, the phase difference between the forward signal and the backward signal at this time is obtainedThe above-mentioned compound is obtained according to the formula (3)_INTherefore, not only the power amplitude information of the front reverse signal but also the phase information are used to obtain more accurate_IN。

In the present step, the first step is carried out,it can be obtained in two ways: acquiring the phase of the forward signal and the phase of the reverse signal, and determining the difference between the phase of the forward signal and the phase of the reverse signal asOr obtaining a first phase difference value between the phase of the forward signal and the phase of the baseband signal, and a second phase difference value between the phase of the reverse signal and the phase of the baseband signal, and determining the difference value between the first phase difference value and the second phase difference value as

Step S506, use S, P_FWD、P_REVAndand calculating the standing-wave ratio.

The relation (4) of standing-wave ratio and reflection coefficient:

$\mathrm{VSWR}=\frac{1+\left|{\mathrm{\Γ}}_L\right|}{1-\left|{\mathrm{\Γ}}_L\right|}---\left(4\right)$

and (4) combining the formulas (2), (3) and (4) to obtain the standing-wave ratio of the antenna port of the base station at the moment.

Preferably, after step S506, the method further includes the step of determining the state of the antenna feeder system by using the standing-wave ratio.

In the embodiment of the invention, three loads with known reflection coefficients are used for calibrating the base station to obtain accurate phase information_LTherefore, the standing-wave ratio of the base station antenna port with higher accuracy is obtained.

Example two

Fig. 6 is a block diagram of a standing-wave ratio detecting apparatus according to a second embodiment of the present invention, including:

an equivalent parameter obtaining module 602, configured to obtain an equivalent parameter value S of a group of base station antenna ports at a frequency point of interest of a base station;

preferably, the equivalent parameter obtaining module 602 is specifically configured to: connecting different known reflection coefficients three times at base station antenna port_LiThe base station transmits the signals of the frequency points of interest to obtain the power P of the corresponding forward signals_FWDiPower P of the reverse signal_REViAnd a phase difference between the forward signal and the reverse signal at this timeObtained by the formula (3)_INi(ii) a Wherein i is 1, 2, 3; will be provided with_INiAnd_Lirespectively substituted into the formula (2) to obtain three equations, and the three equations are used for solving to obtain a vector S₁₁、S₂₂And S₁₂×S₂₁The value of (c).

A power obtaining module 604, configured to obtain power P of a forward signal of a base station antenna port_FWDAnd power P of the reverse signal_REV(ii) a Sample value acquisition P specifically using two-way analog-to-digital converter_FWDAnd P_REV。

A phase difference acquisition module 606 for determining a phase difference between the phases of the forward and reverse signals

Preferably, the first and second electrodes are formed of a metal,the determination of (d) may be: acquiring the phase of the forward signal and the phase of the reverse signal, and determining the difference between the phase of the forward signal and the phase of the reverse signal asOr obtaining a first phase difference value between the phase of the forward signal and the phase of the baseband signal, obtaining a second phase difference value between the phase of the reverse signal and the phase of the baseband signal, and determining the first phase difference value and the second phase difference valueBy a difference of

A standing wave ratio determination module 608 for determining the standing wave ratio according to S, P_FWD、P_REVAndand determining the standing-wave ratio.

The module is specifically configured to determine the standing-wave ratio according to equations (2), (3) and (4).

Preferably, in order to fully utilize the standing wave ratio detected by the invention, the device further comprises an antenna feed system state determining module for determining the state of the antenna feed system according to the standing wave ratio.

The device of the embodiment of the invention uses three loads with known reflection coefficients to calibrate the base station to obtain accurate phase information_LTherefore, the standing-wave ratio of the base station antenna port with higher accuracy is obtained.

In addition, the invention also provides a base station standing-wave ratio detection base station which comprises the detection device. Similarly, the technical solutions of the first embodiment and the second embodiment are applicable to the base station, and are not repeated here.

While the foregoing description shows and describes the preferred embodiments of the present invention, it is to be understood, as noted above, that the invention is not limited to the forms disclosed herein, but is not intended to be exhaustive or to exclude other embodiments and may be used in various other combinations, modifications, and environments and is capable of changes within the scope of the inventive concept described herein, as determined by the above teachings or as determined by the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (10)

1. A standing-wave ratio detection method is characterized by comprising the following steps:

step one, determining equivalent parameter values S of a group of base station antenna ports at a frequency point of interest of a base station;

step two, acquiring the power P of the forward signal of the base station antenna port_FWDPower P of the reverse signal_REVAnd a phase difference value between phases of the forward signal and the reverse signal at this time

Step three, according to the S, P_FWD、P_REVAnddetermining a standing-wave ratio;

wherein, the first step comprises:

connecting different known reflection coefficients three times at base station antenna port_LiThe base station transmits the signals of the frequency points of interest to obtain the power P of the corresponding forward signals_FWDiPower P of the reverse signal_REViAnd the phase difference between the forward signal and the reverse signal at that timeUsing formulasAre respectively obtained_INi(ii) a Wherein i is 1, 2, 3;_INiin order to receive the reflection coefficient of the ith load from the forward signal input end of the radio frequency module to the antenna direction,_Lithe reflection coefficient is the reflection coefficient when the load is connected with the ith load;

will be provided with_INiAnd_Lirespectively substituting into the formulas:

${\mathrm{\Γ}}_L=\frac{{\mathrm{\Γ}}_{IN}-S_{11}}{S_{12}\×S_{21}-S_{11}\×S_{22}+{\mathrm{\Γ}}_{IN}{S}_{22}}$

obtaining three equations, and solving the three equations to obtain S₁₁、S₂₂And S₁₂×S₂₁Value of (A), S₁₁The reflection coefficient of port 1 when matched for port 2; s₂₂The reflection coefficient of port 2 when matched for port 1; s₁₂The reverse transmission coefficient from port 2 to port 1 when matching for port 1; s₂₁Port 1 to port 2 forward transmission coefficients when matched for port 2.

2. The method of claim 1, wherein step three is further followed by:

and step four, determining the state of the antenna feed system according to the standing-wave ratio.

3. The method according to claim 1, wherein the second step comprises:

acquiring the forward power and the reverse power by using a sampling value of an analog-to-digital converter;

obtaining the phase of the forward signal and the phase of the reverse signal through a sampling value of an analog-to-digital converter, and determining the difference value between the phase of the forward signal and the phase of the reverse signal asOr obtaining a first phase difference value between the phase of the forward signal and the phase of the baseband signal, and a second phase difference value between the phase of the reverse signal and the phase of the baseband signal, and determining the difference value between the first phase difference value and the second phase difference value as

4. The method according to any one of claims 1 to 3, wherein the third step comprises: according toAnd determining the standing-wave ratio, wherein,

and is

_LIs the reflection coefficient of the antenna port of the base station,_INis the reflection coefficient looking into the direction of the antenna from the forward signal input of the radio frequency module.

5. A standing-wave ratio detection device, comprising:

the equivalent parameter acquisition module is used for acquiring equivalent parameter values S of a group of base station antenna ports at the frequency point of interest of the base station;

a power obtaining module for obtaining the power P of the forward signal of the base station antenna port_FWDAnd power P of the reverse signal_REV；

A phase difference acquisition module for determining a phase difference between phases of the forward signal and the reverse signal

A standing-wave ratio determination module for determining the standing-wave ratio according to the S, P_FWD、P_REVAnddetermining a standing-wave ratio;

the equivalent parameter obtaining module is specifically configured to: connecting different known reflection coefficients three times at base station antenna port_LiThe base station transmits the signals of the frequency points of interest to obtain the power P of the corresponding forward signals_FWDiPower P of the reverse signal_REViAnd the phase difference between the forward signal and the reverse signal at that timeUsing formulasAre respectively obtained_INi(ii) a Wherein i is 1, 2, 3;_INiin order to receive the reflection coefficient of the ith load from the forward signal input end of the radio frequency module to the antenna direction,_Lithe reflection coefficient is the reflection coefficient when the load is connected with the ith load;

will be provided with_INiAnd_Lirespectively substituting into the formulas:

${\mathrm{\Γ}}_L=\frac{{\mathrm{\Γ}}_{IN}-S_{11}}{S_{12}\×S_{21}-S_{11}\×S_{22}+{\mathrm{\Γ}}_{IN}{S}_{22}}$

obtaining three equations, and solving the three equations to obtain S₁₁、S₂₂And S₁₂×S₂₁Value of (A), S₁₁The reflection coefficient of port 1 when matched for port 2; s₂₂The reflection coefficient of port 2 when matched for port 1; s₁₂The reverse transmission coefficient from port 2 to port 1 when matching for port 1; s₂₁Port 1 to port 2 forward transmission coefficients when matched for port 2.

6. The apparatus of claim 5, further comprising: and the antenna feeder system state determining module is used for determining the state of the antenna feeder system according to the standing-wave ratio.

7. The apparatus of claim 5,

the power acquisition module is used for acquiring the P by using the sampling value of the analog-to-digital converter_FWDAnd P_REV。

8. The apparatus of claim 5, wherein the phase difference obtaining module is specifically configured to:

acquiring the phase of the forward signal and the phase of the reverse signal, and determining the difference between the phase of the forward signal and the phase of the reverse signal asOr obtaining a first phase difference value between the phase of the forward signal and the phase of the baseband signal, and a second phase difference value between the phase of the reverse signal and the phase of the baseband signal, and determining the difference value between the first phase difference value and the second phase difference value as

9. The apparatus according to any one of claims 5 to 8, wherein the standing-wave ratio determining module is specifically configured to:

according toAnd determining the standing-wave ratio, wherein,

and is

_LIs the reflection coefficient of the antenna port of the base station,_INis the reflection coefficient looking into the direction of the antenna from the forward signal input of the radio frequency module.

10. A standing-wave ratio detection base station, characterized in that it comprises a standing-wave ratio detection device according to any of claims 5 to 9.