WO2012151939A1

WO2012151939A1 - Standing wave ratio detection method, device and base station

Info

Publication number: WO2012151939A1
Application number: PCT/CN2011/082630
Authority: WO
Inventors: 马兴望; 向明飞
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-08-15
Filing date: 2011-11-22
Publication date: 2012-11-15
Also published as: CN102938904B; CN102938904A

Abstract

Disclosed are a standing wave ratio detection method, device and base station, belonging to the field of mobile communications. The method includes: determining an equivalent parameter value S of a group of base station antenna ports at the frequency point in which a base station is interested; acquiring the power P_FWD of a forward signal of the base station antenna port, the power P_REV of a backward signal, and the phase difference ∠φ between the phases of the forward signal and the backward signal at this moment; and determining the standing wave ratio according to the S, P_FWD, P_REV and ∠φ. By way of the present invention, on the basis of the amplitude information about the forward and backward signals of the base station, the phase information affecting the standing wave ratio is calibrated using three different negative carriers, and the standing wave ratio of the base station is then calculated using the amplitude and phase information, improving the precision of the standing wave ratio, and thus improving the accuracy for detecting the connection state of the antenna feeder system.

Description

Method, device and base station for detecting standing wave ratio

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

The mobile communication base station needs to transmit an RF signal through an antenna. However, when the NE system (feeder and antenna) has a problem, the downlink signal power cannot be effectively radiated into the space through the antenna. This requires the base station to have the function of detecting whether the antenna feeder system is working normally. The usual detection method is to detect the standing wave ratio of the base station antenna port to reflect whether the antenna feeder system works normally.

At present, the circuit structure for detecting the standing wave ratio of the antenna port of the base station mainly has the following two types: First, the circuit for indirectly obtaining the forward reverse signal of the base station antenna port through the coupler between the power amplifier and the duplexer as shown in FIG. The second structure is a circuit structure of the front reverse signal of the base station antenna port obtained by the coupler at the antenna port of the base station through the duplexer as shown in FIG. 2 .

If the base station can detect the forward reverse signal of the base station antenna port, then when calculating the standing wave, it is only necessary to know the power of the front reverse signal. However, according to the circuit structure shown in FIG. 1 and FIG. 2, it is actually difficult to directly detect the power of the front reverse signal of the base station antenna port, and at least the duplexer adapter exists between the coupler and the base station antenna port. . Since the detected signal is not the signal of the antenna port of the base station, and only the amplitude of the signal is detected and the phase information of the signal is not used to obtain the standing wave ratio, the accuracy error of the obtained standing wave ratio is large, which leads to detection. The status of the antenna feeder system is not accurate. Summary of the invention

The technical problem to be solved by the present invention is to provide an ability to detect using amplitude and phase information. The method, the device and the base station of the standing wave ratio solve the problem that the conventional detection of the standing wave ratio of the base station antenna port does not use the phase information and the error is large, thereby causing the state detection of the antenna feeder system to be inaccurate.

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

Step 1: Determine an equivalent parameter value S of a group of base station antenna ports at the frequency point of interest of the base station; Step 2: Obtain the power PFWD of the forward signal of the base station antenna port, the power PREV of the reverse signal, and the forward direction a phase difference between the phase of the signal and the inverted signal;

Step 3. Determine the standing wave ratio based on S, PFWD, PREV.

The step 3 further includes:

Step 4: Determine a state of the antenna feeder system according to the standing wave ratio.

The step 1 includes:

The base station antenna port connects the load of different known reflection coefficient r _Li three times, and the base station transmits the signal of the frequency of interest to obtain the power of the corresponding forward signal _; the power of the reverse signal ^·, and the forward signal at this time The phase difference from the reverse signal (Pi, using the formula to obtain Γ _Μ ; where i = l, 2, 3; Γ _Μ is the time from the ith load

The reflection coefficient seen from the left to the right of the RF module, r _Li is the reflection coefficient when the ith load is connected; Γ/Μ and i are substituted into the formula:

Three equations are obtained, and the values of 5^, ₂ and are obtained by solving these three equations. The second step includes:

Obtaining the forward power and the reverse power using sample values of an analog to digital converter; acquiring a phase of the forward signal and the reverse signal by sampling values of an analog to digital converter Phase, determining a difference between a phase of the forward signal and a phase of the reverse signal, or acquiring a first phase difference between a phase of the forward signal and a phase of the baseband signal, the reverse A second phase difference between a phase of the signal and a phase of the baseband signal determines a difference between the first phase difference value and the second phase difference value. Among them,

F _L =

r _L is the reflection coefficient of the antenna port of the base station, and r _IN is the reflection coefficient seen from the left side to the right end of the radio frequency module.

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 apparatus, comprising:

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

a power acquisition module, configured to acquire a power PFWD of a forward signal of the base station antenna port and a power PREV of the reverse signal;

a phase difference acquisition module, configured to determine a phase difference between phases of the forward signal and the reverse signal;

The standing wave ratio determining module is configured to determine the standing wave ratio according to the S, PFWD, PREV and the. The device further includes: an antenna feeder system state determining module, configured to determine a state of the antenna feeder system according to the standing wave ratio.

The equivalent parameter obtaining module is configured to: connect the different known reflection coefficients 三次 in the antenna port of the base station three times _; the load i, the base station transmits the signal of the frequency of interest to obtain the power of the corresponding forward signal P _FWDl , the power of the reverse signal Pju, and between the forward signal and the reverse signal at this time Retardation Z, using the formula ¹ ^ / "^ ^ ^ ¹ were obtained _Γ Μ; where i = l, 2, 3;

^FWD

When _Γ Μ i-th load is connected to the RF module from the left end to the right to see the reflection coefficient, _r; i-th contact of reflection coefficient when a load;

Substituting r _M and r _; into the formula:

Three equations are obtained, and the values of 5^, ₂ and are obtained by solving these three equations. The power acquisition module is configured to acquire the P _FWD and the PREV using sample values of the analog to digital converter.

The phase difference acquisition module is configured to:

Obtaining a phase of the forward signal and a phase of the reverse signal, determining a difference between a phase of the forward signal and a phase of the reverse signal as Δφ, or acquiring a phase and a baseband of the forward signal Determining a first phase difference between phases of the signal, a second phase difference between a phase of the reverse signal and a phase of the baseband signal, determining the first phase difference value and the second phase difference value The difference between the two is Ζ. The standing wave ratio determining module is configured to:

i+|r,|

Determine the standing wave ratio according to ra^^^^^j, where

1—丄r _L = and r, _N =

^S n ^{x S} 2r ^S n ^{x S} 22 ^+r iN ^S 22 V brain

In order to solve the above technical problems, according to still another aspect of the present invention, the present invention also provides A standing wave ratio detecting base station includes the standing wave ratio detecting device in the above technical solution. According to the technical solution of the present invention, compared with the prior art, based on the amplitude information of the forward signal and the reverse signal of the base station, the phase information affecting the standing wave ratio is calibrated by using three different loads, and the amplitude is utilized. And the phase information calculates the standing wave ratio, which improves the accuracy of the standing wave ratio, thereby improving the accuracy of detecting the connection state of the antenna feeder system. DRAWINGS

The drawings are intended to provide a further understanding of the invention, and are intended to be a part of the invention. In the drawing:

1 is a schematic structural view of a standing wave ratio detecting circuit in the prior art;

2 is a schematic structural diagram of still another standing wave ratio detecting circuit in the prior art;

3 is a schematic diagram showing an equivalent structure of a structure of a standing wave ratio detecting circuit of the prior art;

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

FIG. 5 is a flowchart of a standing wave ratio detecting method according to Embodiment 1 of the present invention; FIG. 6 is a structural block diagram of a standing wave ratio detecting device according to Embodiment 2 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS In order to make the technical problems, technical solutions and beneficial effects of the present invention more clear and clear, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Embodiment 1

FIG. 3 is a schematic diagram showing an equivalent structure of a structure of a standing wave ratio detecting circuit of the prior art; FIG. 4 is a schematic diagram of an equivalent parameter model of the circuit structure of FIG. 3; Flow chart of the standing wave ratio detection method. The method of the embodiment of the present invention is described below with reference to FIG. 3, FIG. 4 and FIG. Step S502: determining an equivalent parameter value S of a group of base station antenna ports at a frequency point of interest of the base station; whether the circuit structure shown in FIG. 1 or FIG. 2 is equivalent to the circuit structure shown in FIG. According to the structure of the standing wave ratio detecting circuit shown in FIG. 3, the structure diagram of the equivalent parameter model of FIG. 4 can be obtained. To calculate the accurate standing wave ratio of the base station, an accurate reflection coefficient of the base station antenna port is needed.

From the equivalent parameter model structure diagram of Figure 4, the relation (1) can be obtained:

r _ C ^21 ',

L IN - °11 ten

1 ( 1 )

One S x Γι

The relation (2) can be obtained from the relation (1)

(2) where r _IN is the reflection coefficient seen from the left to the right end of the RF module, and r _L is the reflection coefficient of the antenna port of the base station. Both parameters are vectors, including amplitude and phase information.

Where 5 s ₂₂ . s _l2 xs _2l is the equivalent parameter value s of a group of base station antenna ports, and Figure 4 shows the S parameters of four ports. The S parameter is defined by the ratio of two complex numbers, including amplitude and phase information. S 11 is the reflection coefficient of port 1 when port 2 matches; S22 is the reflection coefficient of port 2 when port 1 matches; S 12 is the reverse transmission coefficient of port 2 to port 1 when port 1 matches; S21 is the port when port 2 matches 1 to port 2 forward transmission coefficient. It is worth noting that these parameters are vectors, including not only the amplitude information about the signal, but also the phase information, and once the base station is finalized, 5; S ₂₂ . 5^ x 5^ is fixed.

According to the definition of the voltage reflection coefficient, there is the following formula (3):

Where y and respectively represent the incident voltage and reflected voltage on the left side of the module, i ^ is forward The forward signal power value at the signal coupling, PJU is the reverse signal power value at the reverse signal coupling, which is the phase difference between the forward signal and the reverse signal.

Due to the existing method, the S parameters (including 5; S ₂₂ . S xS _2l ) are approximately equal, and only the power amplitude information of the front reverse signal is used when r _V is sought, and is not used. The phase information, therefore, there is a relatively large error in the resulting base station standing wave ratio. Therefore, in this step, three bases with known reflection coefficients are used to calibrate the base station to obtain an accurate set of S parameters (including 5^, ₂ , S _l2 xS _2l ) with phase information, which are:

Connect the base station antenna port to load 1 with a known S-parameter. The reflection coefficient of this load is Γ ₁ . The base station transmits the signal of the frequency of interest, uses the two analog-to-digital converters to directly acquire the front and reverse signals to obtain the pair of P _FW m and PRE, and then obtains the angle value Z ^ of the reverse signal and the angle value of the forward signal. The phase difference φ of ^^, and then the dish is obtained according to the formula (3).

Same as above, the base station antenna port is connected to the load 2 of the known S parameter, and the reflection coefficient of the load is r ₂ , and the base station transmits the signal of the frequency of interest to obtain the corresponding ^^ ₂ and the phase difference Z ₂ , and then according to (3) ) get r _V2 . It should be noted that Γ _{2 is} not equal to Γ^.

As above, the base station antenna port is connected to the load 3 of the known S parameter, and the reflection coefficient of the load is ₃ . The base station transmits the signal of the frequency of interest to obtain the corresponding _ra3 and the phase difference Z%, and then obtains r _V3 according to the formula (3). It should be noted that Γ _{3 is} not equal to Γ^, nor equal to ₂ .

In the above steps, the selection of the frequency of interest is related to the frequency band information of the base station. For example, if the RRU of a certain type supports the frequency band of 2110-2170 MHz, then the frequency of interest is 2110-2170 MHz, so only the S value of this frequency band needs to be determined. While another model of RRU supports the 925-960MHZ band, then only the S value of the 925-960MHZ band is required.

The r _M , r muscle, r _jV3 and the known r _L2 and r _L3 obtained in the above manner are substituted into the equation (2) to obtain three equations. Use these three equations to solve three unknowns: S . S , S x S _2l . Thus, a set of equivalent parameter values S at the frequency points of interest of the base station can be obtained (including,

S ₂₂ . S x S _2l ), stored in a table of S information about the frequency of interest.

Step S504, acquiring a power P _FWD of the forward signal of the base station antenna port, a power P _{REV of the} reverse signal, and a phase difference value between the forward signal and the reverse signal at this time;

When the base station is working, when it is required to detect the base station standing wave ratio when the base station antenna port is connected to any load, the forward power P _{FWD of the} base station antenna port is obtained by sampling the forward signal and the reverse signal by two analog-to-digital converters. Reverse power Pj^v, then find the phase difference between the forward signal and the reverse signal at this time

^φ , then obtain the r _V mentioned above according to the formula (3), so that not only the power amplitude information of the front reverse signal but also the phase information is used to obtain a relatively accurate r _w .

In this step, the phase of the forward signal and the phase of the reverse signal are obtained, and the phase difference between the phase of the forward signal and the phase of the reverse signal is determined to be Δφ. Or obtaining a first phase difference between a phase of the forward signal and a phase of the baseband signal, a second phase difference between a phase of the reverse signal and a phase of the baseband signal, determining the first phase The difference between the difference and the second phase difference is .

Step S506, using S, P _FWD , P _REV and calculating the standing wave ratio.

The relationship between standing wave ratio and reflection coefficient (4):

The standing wave ratio of the base station antenna port at this time can be obtained by combining equations (2), (3) and (4).

Preferably, after step S506, the step of determining the state of the antenna feeder system by using the standing wave ratio is further included. In the embodiment of the present invention, three bases with known reflection coefficients are used to calibrate the base station to obtain an accurate r _L with phase information, thereby obtaining a standing wave ratio of the base station antenna port with higher accuracy.

Embodiment 2

FIG. 6 is a structural block diagram of a standing wave ratio detecting apparatus according to Embodiment 2 of the present invention, Includes:

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

Preferably, the equivalent parameter obtaining module 602 is configured to: connect three different known reflection coefficient Γ in the base station antenna _interface; * load, the base station transmitting frequency of the signal of interest, to give the corresponding forward power signal _P FWDl, Pju reverse power signal and the phase difference Z between the front case and the inverted signal of the signal, using the formula ₍₃₎ obtained _Γ Μ; where i = l, 2, 3; and the _Γ Μ _Γ; · are substituted into equation (2) to give three equations, three equations solved for using these 5 vector; Χ ₂₁ and the value _2.

The power acquisition module 604 is configured to acquire the power P _{FWD of the} forward signal of the base station antenna port and the power P _{REV of the} reverse signal; and obtain the P _FWD and the PREV using the sample values of the two analog-to-digital converters.

a phase difference acquisition module 606, configured to determine a phase difference between phases of the forward signal and the reverse signal;

Preferably, the determining may be: acquiring a phase of the forward signal and a phase of the reverse signal, determining a difference between a phase of the forward signal and a phase of the reverse signal as φ, or acquiring Determining the first phase difference value and a first phase difference value between a phase of the forward signal and a phase of the baseband signal, a second phase difference between a phase of the reverse signal and a phase of the baseband signal The difference between the second phase difference values is .

The standing wave ratio determination module 608 is used for the roots S, P _FWD , P _REV and determining the standing wave ratio. This module is used to determine the standing wave ratio according to equations (2), (3) and (4).

Preferably, in order to make full use of the standing wave ratio detected by the present invention, the apparatus further comprises an antenna feeder system state determining module for determining the state of the antenna feeder system based on the standing wave ratio.

The apparatus of the embodiment of the present invention uses three loads with known reflection coefficients to calibrate the base station to obtain an accurate r _L with phase information, thereby obtaining a standing wave ratio of the base station antenna port with higher accuracy. In addition, the present invention also provides a base station standing wave ratio detecting base station, including the above detecting device. Similarly, the technical solutions of the first embodiment and the second embodiment can be applied to the base station, and are not repeatedly described herein.

The above description shows and describes a preferred embodiment of the present invention, but as described above, it should be understood that the present invention is not limited to the form disclosed herein, and should not be construed as being Other combinations, modifications, and environments are possible and can be modified by the teachings of the above teachings or related art within the scope of the inventive concept described herein. All changes and modifications made by those skilled in the art are intended to be within the scope of the appended claims.

Industrial applicability

According to the invention, based on the amplitude information of the forward signal and the reverse signal of the base station, the phase information affecting the standing wave ratio is calibrated by using three different loads, and the standing wave ratio is calculated by using the amplitude and phase information, thereby improving The accuracy of the standing wave ratio is improved, and the accuracy of detecting the connection state of the antenna feeder system is improved.

Claims

Claim

1. A method for detecting standing wave ratio, comprising:

Step 1: Determine the equivalent parameter value S of a group of base station antenna ports at the frequency point of interest of the base station; Step 2: Obtain the power of the forward signal of the base station antenna port p _FWD , the power of the reverse signal

P _REV , and the phase difference between the phase of the forward signal and the reverse signal at this time;

Step 3. According to the 8, P _FWD , PREV and determining the standing wave ratio.

2. The method according to claim 1, wherein the step 3 further comprises: Step 4: determining a state of the antenna feeder system according to the standing wave ratio.

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

The base station antenna port connects the load of different known reflection coefficient r _Li three times, and the base station transmits the signal of the frequency of interest to obtain the power of the corresponding forward signal _; the power of the reverse signal Α^·, and the forward direction The phase difference between the signal and the reverse signal, using the formula factory _

IN obtains Γ _Μ respectively; where i=l, 2, 3; Γ _Μ is the time from the ith load

RF module on the left side to the right look reflection coefficient, r _Li is connected to the i-th reflection coefficient when the load; the _Γ Μ and R _< are substituted into the formula: γ ^x IN ^ ll

Χ ^2Γ^11 ^Χ +Γ _Λ ^ ₂₂

Three equations are obtained, and the values of 5; ₂ and ^ ₂₁ are obtained by solving these three equations.

4. The method according to claim 1, wherein the step two comprises:

Acquiring the forward power and the reverse power using sample values of the analog-to-digital converter; obtaining a phase of the forward signal and a phase of the reverse signal by sampling values of the analog-to-digital converter, determining the front a difference between a phase of the signal and a phase of the reverse signal, or a first phase difference between a phase of the forward signal and a phase of the baseband signal, And determining a difference between the phase of the reverse signal and the phase of the baseband signal to determine a difference between the first phase difference value and the second phase difference value.

The method according to any one of claims 1 to 4, wherein the step three comprises: according to ra

6. A standing wave ratio detecting device, comprising:

a power acquisition module, configured to acquire a power P _{FWD of a} forward signal of the base station antenna port and a power PREV of the reverse signal;

a phase difference acquisition module, configured to determine a phase difference Z between phases of the forward signal and the reverse signal;

The standing wave ratio determining module is configured to determine a standing wave ratio according to the S, P _FWD , P _REV .

The method according to claim 6, wherein the device further comprises: an antenna feeder system state determining module, configured to determine a state of the antenna feeder system according to the standing wave ratio.

8. The apparatus according to claim 6, wherein the equivalent parameter obtaining module is configured to: connect, at a base station antenna port three times, a load i of a different known reflection coefficient F _Li , and the base station transmits a signal of a frequency of interest, Obtaining the power of the corresponding forward signal _; the power of the reverse signal Pju,

Obtaining Γ _Μ respectively; where i=l, 2, 3; Γ _Μ is the reflection coefficient seen from the left to the right end of the RF module when the i-th load is connected, Γ _; · the reflection coefficient when the i-th load is connected;

Substituting Γ _Μ and r _; into the formula:

9. The apparatus according to claim 6, wherein

The power acquisition module is configured to acquire the P _FWD and the sampled value of the analog to digital converter

P REV.

10. The apparatus according to claim 6, wherein the phase difference acquisition module is configured to: acquire a phase of the forward signal and a phase of the reverse signal, determine a phase of the forward signal, and the The difference of the phase of the reverse signal is Δφ, or the first phase difference between the phase of the forward signal and the phase of the baseband signal is obtained, and the phase between the phase of the reverse signal and the phase of the baseband signal The two phase difference values are determined to be Ζ between the first phase difference value and the second phase difference value.

The apparatus according to any one of claims 6 to 9, wherein the standing wave ratio determining module is configured to:

Γ, = ^τ and r _{w =}

S _l2 x S _2l -S xS ₂₂ +T _IN S ₂₂ ^P FWD r _L is the reflection coefficient of the base station antenna port, l] _N is the reflection coefficient seen from the left to the right end of the RF module.

12. A standing wave ratio detecting base station, comprising a station according to any one of claims 6-11 Wave ratio detection device.