CN112235058B - Standing-wave ratio detection system and method and radio remote unit with system - Google Patents
Standing-wave ratio detection system and method and radio remote unit with system Download PDFInfo
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- CN112235058B CN112235058B CN202011083882.4A CN202011083882A CN112235058B CN 112235058 B CN112235058 B CN 112235058B CN 202011083882 A CN202011083882 A CN 202011083882A CN 112235058 B CN112235058 B CN 112235058B
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- H04B17/00—Monitoring; Testing
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- H04B17/101—Monitoring; Testing of transmitters for measurement of specific parameters of the transmitter or components thereof
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- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The invention discloses a standing-wave ratio detection system, a standing-wave ratio detection method and a radio remote unit with the system, wherein a data cache module of the system is controlled by a controller to work cooperatively with a front reverse direction selector switch of the radio remote unit, the data cache module receives sending data and feedback data of the radio remote unit, the data cache module sends the data to a related power statistics module, the related power statistics module outputs results to a power statistics result cache module, and the power statistics result cache module respectively and independently stores power data under the control of the controller. The invention ensures the data correlation by controlling the cooperative work of the data caching module and the front and back switches, and provides possibility for accurately calculating the standing-wave ratio. By carrying out data correlation operation and normalizing the feedback data according to the corresponding sending data, the fluctuation of the sending data is counteracted, and the standing-wave ratio calculation is subsequently carried out without being influenced by the data fluctuation, thereby improving the calculation accuracy.
Description
Technical Field
The present invention relates to a standing-wave ratio detection technology, and in particular, to a standing-wave ratio detection system, a method and a remote radio unit with the system.
Background
The position of a Radio Remote Unit (RRU) in the field of wireless communication is very important. The radio remote unit mainly completes the following functions: performing digital up-conversion on baseband data of a baseband to convert the baseband data into an intermediate frequency digital signal, converting the intermediate frequency digital signal into an analog signal through a digital-to-analog converter, performing up-conversion and amplification on a radio frequency small signal part, and finally amplifying the signal through a Power Amplifier (PA) and transmitting the amplified signal through an antenna; the uplink part receives user signals, the user signals are amplified and down-converted into intermediate frequency analog signals through a Low Noise Amplifier (LNA) and a radio frequency small signal part, the intermediate frequency analog signals are converted into digital intermediate frequency signals through an analog-digital converter, and the digital intermediate frequency signals are finally transmitted to a baseband unit through digital down-conversion.
A Power Amplifier (PA) is the most basic component of a radio remote unit. The output of the power amplifier is a radio frequency high-power signal, if the standing-wave ratio of the output port of the power amplifier is not good, a large part of the output signal can be reflected to the power amplifier, and the reflected signal can easily cause the self-excitation of the power amplifier and the burnout of the power amplifier, so that the standing-wave ratio detection function of the output port of the power amplifier is of great importance in a radio frequency remote unit system. The remote radio unit detects the standing wave ratio of the output port of the power amplifier through the standing wave ratio detection function to give a system alarm or turn off the power amplifier.
The traditional standing-wave ratio detection scheme is that the standing-wave ratio is calculated by detecting the forward feedback power and the directional feedback power in a time-sharing manner, and in practical application, the input signal of the power amplifier fluctuates greatly, so that large errors exist when the standing-wave ratio is calculated through two irrelevant power statistics values due to the fact that the input signal power of the power amplifier at the time points of two power detections is different. The standing-wave ratio detection error is large, which may cause the power amplifier to be turned off by mistake or burnt out. Therefore, in the remote radio system, the accuracy of the detection of the standing-wave ratio is a problem worthy of intensive study.
Disclosure of Invention
The invention aims to provide a standing-wave ratio detection system and a method with more accurate results.
Another object of the present invention is to provide a remote radio unit with the above standing-wave ratio detection system.
The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.
According to an aspect of the present invention, there is provided a system for detecting a standing-wave ratio of a remote radio unit, comprising a data caching module, a controller, a relevant power statistics module and a power statistics caching module, the data buffer module is controlled by the controller to work with a front reverse selector switch of the remote radio unit, the data buffer module receives forward sending data, forward feedback data, reverse sending data and reverse feedback data of the remote radio unit, the data caching module sends data to the relevant power statistic module, the relevant power statistic module outputs results to the power statistic result caching module, the power statistical result caching module separately stores the forward sending data power, the forward feedback data power, the reverse sending data power and the reverse feedback data power respectively under the control of the controller.
In an embodiment, the system further includes a data correlation operation module, the data correlation operation module is connected with the data caching module and the correlation power statistics module, and the data correlation operation module performs correlation calculation on the forward sending data, the forward feedback data, the reverse sending data and the reverse feedback data through a data correlation algorithm; and the data correlation operation module controls the data caching module to output the correlation data to the correlation power statistic module.
In one embodiment, the data correlation algorithm of the system is a convolution method.
In an embodiment, the data correlation operation module of the system records the position where the feedback data is aligned with the corresponding sending data, and controls the data cache module to output the correlation data to the correlation power statistics module through address offset.
In an embodiment, the data correlation operation module of the system further normalizes the feedback data according to the corresponding transmission data.
In an embodiment, the storage length of the transmission data in the data caching module of the system is greater than the storage length of the feedback data.
In an embodiment, the data correlation operation module of the system adopts a dual-port RAM.
In one embodiment, the correlation power statistics module of the system performs a sum operation of squaring the real part and the imaginary part of the input data respectively, and then performs an accumulation operation of the sum of squares of the data of a specified length.
According to another aspect of the present invention, a radio remote unit is further provided, including the standing-wave ratio detection system described in any of the above embodiments, further including a forward-reverse switch, a power amplifier, and a CPU, where the forward-reverse switch is controlled by the controller, an output end of the power amplifier generates a forward feedback signal and a reverse feedback signal, and the power statistics buffer module outputs the statistics to the CPU for performing standing-wave ratio calculation.
According to another aspect of the present invention, there is also provided a method for detecting a standing-wave ratio of a remote radio unit, including the following steps:
when a forward and reverse selector switch of the radio remote unit is arranged in a forward direction, the data cache module receives forward transmission data and forward feedback data of the radio remote unit, and stores the data into a forward transmission data power storage space and a forward feedback data power storage space of the power statistics result cache module after power statistics is carried out by the relevant power statistics module;
when the front reverse direction change-over switch of the radio remote unit is arranged in the reverse direction, the data caching module receives reverse sending data and reverse feedback data of the radio remote unit, and stores the data into a reverse sending data power storage space and a reverse feedback data power storage space of the power statistical result caching module after power is counted by the related power statistical module.
The embodiment of the invention has the beneficial effects that: by controlling the data caching module and the front reverse switch to work cooperatively, the sending data and the corresponding feedback data can be stored in the power statistical result caching module in a switching period of the front reverse switch, the data correlation is ensured, a required data source is provided for the subsequent data correlation operation, and the possibility is provided for accurately calculating the standing-wave ratio.
Preferably, the data correlation operation module is arranged and performs correlation operation on the sending data and the feedback data, so that the feedback data and the sending data in the same forward and reverse switch switching period are aligned in a correlation manner, and the influence caused by phase difference is reduced.
Preferably, the feedback data is normalized according to the corresponding sending data, so that the pulsation of the sending data is counteracted, and the standing-wave ratio calculation is subsequently performed without being influenced by data fluctuation, thereby improving the calculation accuracy.
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In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
The above features and advantages of the present disclosure will be better understood upon reading the detailed description of embodiments of the disclosure in conjunction with the following drawings. In the drawings, components are not necessarily drawn to scale, and components having similar relative characteristics or features may have the same or similar reference numerals.
FIG. 1 is a block diagram of the modules of an embodiment of the system of the present invention;
FIG. 2 is a logic diagram of calculation of a correlation operation module according to an embodiment of the present invention;
FIG. 3 is a control logic diagram of a controller of an embodiment of the present invention;
wherein: 1-a data caching module; 2-a data correlation operation module; 3-a correlation power statistics module; 4-a power result caching module; 5-a power amplifier; 6-a forward reverse transfer switch; 7-a controller.
Detailed Description
The invention is described in detail below with reference to the figures and specific embodiments. It is noted that the aspects described below in connection with the figures and the specific embodiments are only exemplary and should not be construed as imposing any limitation on the scope of the present invention.
As shown in fig. 1, an embodiment of the present invention discloses a system for detecting a standing-wave ratio of a remote radio unit, including a data caching module 1, a controller 7, a relevant power statistics module 3, and a power statistics caching module 4. The data buffer module 1 cooperates with the forward/backward switch 6 of the remote radio unit under the control of the controller 7, that is, the data write control of the data buffer module 1 is generated by the controller 7, the controller 7 controls the forward/backward switch 6 and the data buffer module 1 simultaneously through the system (CPU or DPD) scheduling of the remote radio unit, so as to ensure that the transmission data and the feedback data are in the same switching period, and the control logic of the controller 7 is as shown in fig. 3.
Radio remote unit generates forward transmission data TX OPD Forward feedback data OPD, reverse transmission data TX RPD And reverse feedback data RPD. The data caching module 1 receives the data and sends the data to the relevant power statistic module 3, and the relevant power statistic module 3 outputs the statistic result to the power statistic result caching module 4. Control of the power statistics caching module 4 at the controller 7Separately storing TX under control OPD Power, OPD power, TX RPD Power and RPD power. Separate storage, as used herein, may be by TX OPD Power, OPD power, TX RPD Power, RPD power are implemented separately from the registers. The result of the calculation completed by the relevant power statistic module 3 under the instruction of the controller 7 is automatically written into the corresponding register.
The detection method corresponding to the standing-wave ratio detection system comprises the following steps: when the forward/reverse switch 6 of the remote radio unit is placed in the forward direction, the data buffer module 1 receives the forward transmission data TX of the remote radio unit OPD And the forward feedback data OPD, the TX stored in the power statistic result buffer module 4 after the power is counted by the related power statistic module 3 OPD Power storage space and OPD power storage space; when the forward/backward switch 6 of the remote radio unit is in the backward direction, the data buffer module 1 receives the backward transmission data TX of the remote radio unit RPD And reverse feedback data RPD, which is stored in TX of power statistic result buffer module after power statistic by related power statistic module RPD Power storage space and RPD power storage space.
According to the standing-wave ratio detection system and method, the controller 7 controls the front-reverse direction selector switch 6, the data cache module 1 and the power statistics result cache module 4 to cooperatively act, so that the sending data and the corresponding feedback data can be stored in the cache in one switching period of the front-reverse direction switch, the correlation of the data is guaranteed, a required data source is provided for subsequent data correlation operation, and the possibility is provided for accurately calculating the standing-wave ratio.
Furthermore, the system for detecting the standing-wave ratio may further include a data correlation operation module 2, the data correlation operation module 2 is connected to the data caching module 1 and the correlation power statistics module 3, and the data correlation operation module 2 performs a data correlation algorithm on the forward transmission data TX OPD Forward feedback data OPD, reverse transmission data TX RPD And the reverse feedback data RPD is subjected to correlation calculation, and the data correlation operation module 2 controls the data cache module 1 to output the correlation data to the correlation power statistic module 3.
As shown in fig. 2, the working process of the data correlation operation module 2 is as follows: when the data cache of the data cache module 1 is finished, a mark signal is given to the data correlation operation module 2, and the data correlation operation module 2 starts to perform data correlation operation; after the data correlation operation is completed, the data correlation operation module 2 keeps a data correlation peak, namely a position where the feedback data is aligned with the sending data; then the data correlation operation module 2 controls the data buffer module 1 to output the sending data and the feedback data to the correlation power statistic module through the address offset.
In a possible embodiment, the algorithm used by the data correlation operation module 2 is a convolution method, and other algorithms may also be used as long as the alignment position of the transmission data and the feedback data can be found out.
In a possible embodiment, the data correlation operation module 2 may further normalize the feedback data according to the corresponding transmission data, so that fluctuation of the transmission data is offset, and the standing-wave ratio calculation of the normalized forward feedback data and the normalized reverse feedback data is not affected by fluctuation of the transmission data, so that the standing-wave ratio can be accurately calculated.
The data writing in the data cache module 1 can consider the delay of the feedback data relative to the sending data, and properly delay the writing time of the sending data, and in addition, because the feedback data needs to carry out correlation operation on the sending data, the storage length of the sending data should be longer than that of the feedback data, so as to ensure that the feedback data can be completely used by the subsequent correlation power statistic module 3;
preferably, the data correlation operation module adopts a dual-port RAM, and data can be read out while data is written in, so that the calculation time can be effectively saved.
In addition, the correlation power statistics module 3 performs summation after performing square operation on the real part and the imaginary part of the input data respectively, and then performs accumulation operation on the sum of squares of the data with the specified length, which is the prior art, and therefore is not described again.
As will be readily understood by those skilled in the art, based on the above standing-wave ratio detection system, an embodiment of the present invention further provides a remote radio unit, which includes the standing-wave ratio detection system in any of the foregoing embodiments, and further includes a forward/reverse switch 6 of the remote radio unit itself, a Power Amplifier (PA)5, and a CPU (not shown in the figure), where the forward/reverse switch 6 is controlled by the controller 1, an output end of the power amplifier 5 generates a forward feedback signal and a reverse feedback signal, and the power statistics buffer module 4 outputs the statistics to the CPU for performing standing-wave ratio calculation.
While, for purposes of simplicity of explanation, the methodologies are shown and described as a series of acts, it is to be understood and appreciated that the methodologies are not limited by the order of acts, as some acts may, in accordance with one or more embodiments, occur in different orders and/or concurrently with other acts from that shown and described herein or not shown and described herein, as would be understood by one skilled in the art.
The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
The above description is only a preferred example of the present application and should not be taken as limiting the present application, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present application should be included in the scope of the present application.
Claims (9)
1. A remote radio unit standing-wave ratio detection system is characterized in that: the remote radio unit comprises a data caching module, a controller, a related power statistical module and a power statistical result caching module, wherein the data caching module is controlled by the controller to work cooperatively with a forward and reverse selector switch of the remote radio unit, the data caching module receives forward sending data, forward feedback data, reverse sending data and reverse feedback data of the remote radio unit, the data caching module sends the data to the related power statistical module, the related power statistical module outputs results to the power statistical result caching module, and the power statistical result caching module respectively and independently stores the forward sending data power, the forward feedback data power, the reverse sending data power and the reverse feedback data power under the control of the controller;
the data correlation operation module is connected with the data caching module and the correlation power statistic module and performs correlation calculation on the forward sending data, the forward feedback data, the reverse sending data and the reverse feedback data through a data correlation algorithm; and the data correlation operation module controls the data caching module to output the correlation data to the correlation power statistic module.
2. The remote radio unit standing wave ratio detection system according to claim 1, wherein: the data correlation algorithm is a convolution method.
3. The remote radio unit standing wave ratio detection system according to claim 2, wherein: the data correlation operation module records the alignment position of the feedback data and the corresponding sending data, and controls the data cache module to output the correlation data to the correlation power statistic module through address offset.
4. The remote radio unit standing wave ratio detection system according to claim 3, wherein: and the data correlation operation module is also used for normalizing the feedback data according to the corresponding sending data.
5. The remote radio unit standing wave ratio detection system according to claim 1, wherein: the storage length of the sending data in the data caching module is larger than that of the feedback data.
6. The system according to claim 1, wherein the data correlation operation module employs a dual port RAM.
7. The system according to claim 1, wherein the correlation power statistic module sums the squared real and imaginary parts of the inputted data respectively, and then sums the summed squared data of the specified length.
8. A remote radio unit, comprising: the standing-wave ratio detection system comprises the standing-wave ratio detection system as claimed in any one of claims 1 to 7, and further comprises a forward and reverse direction switch, a power amplifier and a CPU, wherein the forward and reverse direction switch is controlled by a controller, the output end of the power amplifier generates a forward feedback signal and a reverse feedback signal, and the power statistic result caching module outputs the statistic result to the CPU for standing-wave ratio calculation.
9. A method for detecting standing-wave ratio of Remote Radio Unit (RRU) is characterized by comprising the following steps:
when a forward and reverse selector switch of the radio remote unit is arranged in a forward direction, the data cache module receives forward transmission data and forward feedback data of the radio remote unit, and stores the data into a forward transmission data power storage space and a forward feedback data power storage space of the power statistics result cache module after power statistics is carried out by the relevant power statistics module;
when the front reverse change-over switch of the radio remote unit is arranged in the reverse direction, the data caching module receives reverse sending data and reverse feedback data of the radio remote unit, and stores the data after power statistics is carried out by the relevant power statistics module into a reverse sending data power storage space and a reverse feedback data power storage space of the power statistics result caching module;
the data correlation operation module performs correlation calculation on the forward sending data, the forward feedback data, the reverse sending data and the reverse feedback data through a data correlation algorithm;
and the data correlation operation module controls the data caching module to output the correlation data to the correlation power statistic module.
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| CN101106766B (en) * | 2007-07-18 | 2010-06-02 | 华为技术有限公司 | Indoor unit and outdoor unit for distributed base station and distributed base station |
| CN101834677B (en) * | 2010-03-11 | 2013-12-04 | 京信通信系统（中国）有限公司 | Base band power statistic-based standing wave detecting system and method for radio frequency remote system |
| CN101945399B (en) * | 2010-09-03 | 2013-07-03 | 京信通信系统（中国）有限公司 | Distributed base station |
| CN103401624B (en) * | 2013-08-20 | 2015-06-24 | 武汉邮电科学研究院 | Method for detecting SWR (standing-wave ratio) of PDD (Frequency Division Duplex) LTE (Long Term Evolution) RRU (Remote Radio Unit) |
| CN106686763B (en) * | 2016-12-01 | 2020-06-09 | 邦讯技术股份有限公司 | LTE base station system and cell merging and splitting method |
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Effective date of registration: 20230315 Address after: No. 138, Taodu Road, Dingshu Town, Yixing City, Wuxi City, Jiangsu Province, 214200 Patentee after: JIANGSU HENGXIN TECHNOLOGY Co.,Ltd. Patentee after: JIANGSU HENGXIN WIRELESS TECHNOLOGY Co.,Ltd. Address before: No. 138, Taodu Road, Dingshu Town, Yixing City, Wuxi City, Jiangsu Province, 214200 Patentee before: Jiangsu Hengxin Zhonglian Communication Technology Co.,Ltd. |