FI129935B - A method for recognising an incorrectly operating antenna in a communication network - Google Patents

Abstract

A computer implemented method for recognizing an incorrectly operating antenna in a cell of a communication network. The method consist of obtaining (410) performance indicators of a cell or cells, wherein the performance indicators comprises a handover indicator and/or a channel quality indicator and/or a throughput indicator and/or a diversity mode indicator; comparing (420, 430, 440, 450) the performance indicators to pre-set respective threshold values; and providing (460) output information indicating that the antenna is operating incorrectly responsive to detecting that at least any two of the performance indicators have triggered.

Description

A METHOD FOR RECOGNISING AN INCORRECTLY OPERATING ANTENNA IN

A COMMUNICATION NETWORK

TECHNICAL FIELD

The present disclosure generally relates to performance analysis of a communication network. The disclosure relates particularly, though not exclusively, to a method for recognition of an incorrectly operating antenna in a cell of a communication network.

BACKGROUND

This section illustrates useful background information without admission of any technique described herein representative of the state of the art.

Cellular communication networks are complex systems comprising a plurality of cells serving users of the network. When users of the communication network move in the area of the network, connections of the users are seamlessly handed over between cells of the network. There are various factors that affect operation of individual cells and co-operation between the cells. In order for the communication network to operate as intended and to provide planned quality of service, cells of the communication network need to operate as planned. For example, the cells need to provide sufficient coverage without too much interfering with operation of neighboring cells. — Multiple-input multiple output (MIMO) technology is a radio frequency (RF) communications technology using multiple transmission and receiving antennas.

O MIMO enables using multipath propagation wherein a signal is multiplexed to

N multiple transmitting antennas and sent in parallel to multiple receiving antennas.

N The intended operation of a MIMO system requires that a signal is multiplexed to

E 25 correct antennas. If cables transmitting the signal to antennas are connected to 2 incorrect antennas, a MIMO system does not operate as intended. The challenge is

O to identify such antenna towers of a communication network where cables are

O connected to incorrect antennas. US 2010120415 discloses using test signals for determining configuration of antennas and/or detecting faults. Now a new approach for identifying such antennas is provided.

SUMMARY

The appended claims define the scope of protection. Any examples and technical descriptions of apparatuses, products and/or methods in the description and/or drawings not covered by the claims are presented not as embodiments of the invention but as background art or examples useful for understanding the invention.

According to a first example aspect of the present invention, there is provided a computer implemented method for recognizing an incorrectly operating antenna in a cell of a communication network. The method comprises obtaining performance indicators of a cell or cells, wherein the performance indicators comprises a handover indicator and/or a channel quality indicator and/or a throughput indicator and/or a diversity mode indicator; comparing the performance indicators to pre-set respective threshold values; and providing output information indicating that the antenna is operating incorrectly responsive to detecting that at least any two of the performance indicators have triggered.

In an example embodiment, the output information indicating that the antenna is operating incorrectly is provided responsive to detecting that at least any three of the performance indicators have triggered.

In an example embodiment, the output information indicating that the antenna is — operating incorrectly is provided responsive to detecting that the handover indicator

O and the channel guality indicator and the throughput indicator and the diversity mode 5 indicator have all triggered.

N 25 In an example embodiment, the incorrect antenna operation is identified as an

E: incorrectly connected radio signal cable. & In an example embodiment, the handover indicator comprises two handover

S indicators, a first handover indicator indicating handovers within a cell and a second

N handover indicator indicating handovers between cells, and wherein the first and second handover indicator values have separate threshold values.

In an example embodiment, the handover indicator comprises a ratio of two handover indicators, a first handover indicator indicating handovers within a cell and a second handover indicator indicating handovers between cells.

In an example embodiment, the diversity mode indicator indicates a usage of different layers of a 2x2 or 4x4 MIMO communication system.

In an example embodiment, the diversity mode indicator further comprises MIMO configuration data.

According to a second example aspect of the present invention, there is provided an apparatus comprising a processor and a memory including computer program code; the memory and the computer program code configured to, with the processor, cause the apparatus to perform the method of the first aspect or any related embodiment.

According to a third example aspect of the present invention, there is provided a computer program comprising computer executable program code which when executed by a processor causes an apparatus to perform the method of the first aspect or any related embodiment.

According to a fourth example aspect there is provided a computer program product comprising a non-transitory computer readable medium having the computer program of the third example aspect stored thereon.

According to a fifth example aspect there is provided an apparatus comprising means for performing the method of the first aspect or any related embodiment.

N Any foregoing memory medium may comprise a digital data storage such as a data . disc or diskette, optical storage, magnetic storage, holographic storage, opto- = magnetic storage, phase-change memory, resistive random access memory, _ 25 magnetic random access memory, solid-electrolyte memory, ferroelectric random & access memory, organic memory or polymer memory. The memory medium may & be formed into a device without other substantial functions than storing memory or

S it may be formed as part of a device with other functions, including but not limited to

N a memory of a computer, a chip set, and a sub assembly of an electronic device.

Different non-binding example aspects and embodiments have been illustrated in the foregoing. The embodiments in the foregoing are used merely to explain selected aspects or steps that may be utilized in different implementations. Some embodiments may be presented only with reference to certain example aspects. It should be appreciated that corresponding embodiments may apply to other example aspects as well.

BRIEF DESCRIPTION OF THE FIGURES

Some example embodiments will be described with reference to the accompanying figures, in which:

Fig. 1 schematically shows a scenario according to an example embodiment;

Fig. 2 shows a block diagram of an apparatus according to an example embodiment;

Figs. 3A and 3B show an example of MIMO antennas; and

Fig. 4 shows a flow chart according to an example embodiment.

DETAILED DESCRIPTION

In the following description, like reference signs denote like elements or steps.

Fig. 1 shows an example scenario according to an embodiment. The scenario shows a communication network 101 comprising a plurality of cells and base station sites and other network devices, and an automated system 111 configured to implement recognition of incorrectly operating antenna in a cell of a communication network.

In an embodiment of the invention the scenario of Fig. 1 operates as follows: In

N phase 11, the automated system 111 obtains performance indicators and other data . from a cell or cells of a base station site of the network.

O

< In phase 12, the automated system 111 uses the received performance indicators = 25 to monitor and analyze operation of the cells to detect problems in operation of one a e or more antennas of the base station site.

N o 2 In phase 13, any determined problems are output for further actions such as for

QA

S example maintenance of the base station site.

Fig. 2 shows a block diagram of an apparatus 20 according to an embodiment. The apparatus 20 is for example a general-purpose computer or server or some other electronic data processing apparatus. The apparatus 20 can be used for implementing at least some embodiments of the invention. That is, with suitable configuration the apparatus 20 is suited for operating for example as the automated 5 system 111.

The apparatus 20 comprises a communication interface 25; a processor 21; a user interface 24; and a memory 22. The apparatus 20 further comprises software 23 stored in the memory 22 and operable to be loaded into and executed in the processor 21. The software 23 may comprise one or more software modules and can be in the form of a computer program product.

The processor 21 may comprise a central processing unit (CPU), a microprocessor, a digital signal processor (DSP), a graphics processing unit, or the like. Fig. 2 shows one processor 21, but the apparatus 20 may comprise a plurality of processors.

The user interface 24 is configured for providing interaction with a user of the apparatus. Additionally or alternatively, the user interaction may be implemented through the communication interface 25. The user interface 24 may comprise a circuitry for receiving input from a user of the apparatus 20, e.g., via a keyboard, graphical user interface shown on the display of the apparatus 20, speech recognition circuitry, or an accessory device, such as a headset, and for providing output to the user via, e.g., a graphical user interface or a loudspeaker.

The memory 22 may comprise for example a non-volatile or a volatile memory, such as a read-only memory (ROM), a programmable read-only memory (PROM),

N erasable programmable read-only memory (EPROM), a random-access memory

N (RAM), a flash memory, a data disk, an optical storage, a magnetic storage, a smart

S 25 card, or the like. The apparatus 20 may comprise a plurality of memories. The & memory 22 may serve the sole purpose of storing data, or be constructed as a part

E: of an apparatus 20 serving other purposes, such as processing data.

S The communication interface 25 may comprise communication modules that

N implement data transmission to and from the apparatus 20. The communication

N 30 modules may comprise a wireless or a wired interface module(s) or both. The wireless interface may comprise such as a WLAN, Bluetooth, infrared (IR), radio frequency identification (RF ID), GSM/GPRS, CDMA, WCDMA, LTE (Long Term

Evolution) or 5G radio module. The wired interface may comprise such as Ethernet or universal serial bus (USB), for example. The communication interface 25 may support one or more different communication technologies. The apparatus 20 may additionally or alternatively comprise more than one of the communication interfaces 25.

A skilled person appreciates that in addition to the elements shown in Fig. 2, the apparatus 20 may comprise other elements, such as displays, as well as additional circuitry such as memory chips, application-specific integrated circuits (ASIC), other processing circuitry for specific purposes and the like. Further, it is noted that only one apparatus is shown in Fig. 2, but the embodiments of the invention may equally be implemented in a cluster of shown apparatuses.

Figs. 3A and 3B illustrate an example of a multiple-input and multiple-output (MIMO) system. In Fig. 3A a base station comprises a radio module 300 connected to plurality of antenna elements 310, 320, 330, and 340. Antenna elements 310 and 320 serve a first sector of the base station and antenna elements 330 and 340 serve a second sector of the base station. In the example of Fig. 3A, two MIMO layers 315, 325, 335, 345 are shown for both sectors. Layers 315 and 325 may be communicating at the same frequency using e.g. polarization multiplexing or spatial multiplexing. A MIMO system may have more than two layers. First and second sectors may be partially overlapping antenna directions. Antenna element 310 transmits/receives MIMO layer 315 and antenna element 320 transmits/receives

MIMO layer 325. MIMO layers 315 and 325 serve a first sector. Antenna elements

N 330 and 340 transmit/receive MIMO layers 335 and 345, respectively. MIMO layers . 25 2335 and 345 serve a second sector. Multiple MIMO layers in a sector may = communicate with a single user or with multiple users.

N z A data stream to a single user in sector 301 may be split to two streams to be sent

N in two layers 315 and 325 by antennas 310 and 320, respectively. Antennas 310 & and 320 are connected to device 300A using connectors 301 and 302, respectively.

N 30 Antennas 330 and 340 are connected to device 300B using connectors 303 and

N 304, respectively. Devices 300A and 300B may be transmitter/receiver units which may have multiple transmitter/receiver ports. Connectors 301-304 may be cables or wires. Fig. 3B illustrates an example wherein connectors 302 and 303 are incorrectly connected to antennas 330 and 320, respectively. In such an example a data stream is multiplexed to antennas operating at different sectors and the MIMO system does not operate properly as intended.

An example embodiment of a method for recognizing incorrectly operating antenna in a cell of a communication network is shown in Fig. 4. The method of Fig. 4 comprises the following phases: 410: Performance indicators of a cell or cells of a network are gathered. In this example, the performance indicators comprise a handover indicator, a channel quality indicator, a throughput indicator, and a diversity mode indicator. It is to be noted that in some other embodiments all of these performance indicators are not necessarily needed. Other performance indicators, MIMO configuration data, or other network configuration data may also be gathered. 420: A handover indicator is compared to its pre-set threshold value. If the indicator does not trigger, the process may stop. The handover indicator may indicate a number or a rate of handovers within a cell and/or handovers between cells. In an embodiment, the handover indicator comprises two handover indicators, a first handover indicator indicating handovers within a cell and a second handover indicator indicating handovers between cells of the network. The first and second handover indicators may have separate pre-set threshold values. In another embodiment, the handover indicator comprises a ratio of two handover indicators, a first handover indicator indicating handovers within a cell and a second handover - indicator indicating handovers between cells of the network. In some example

O embodiments, the handover indicator is a HO ratio parameter between sectors

N 25 and/or an ATT INTRA ENB HO parameter. In some example embodiments, the

S handover indicator triggers if a handover ratio between sectors is below a threshold z value 1.007 — 1.045 and a number of handovers inside a cell is greater than a e threshold value 3000 — 10000. 3 430: A channel quality indicator is compared to its pre-set threshold value. If the

S 30 indicator does not trigger, the process may stop. In an example embodiment, the channel quality indicator is an avg COl parameter. In some example embodiments,

the channel quality indicator is the COl defined in 3GPP standard. In an embodiment, the channel quality indicator triggers if it is greater than a threshold value 7 — 9. In an example embodiment, the threshold value is 8. 440: A throughput indicator is compared to its pre-set threshold value. If the indicator does not trigger, the process may stop. The throughput indicator may indicate average, maximum or minimum throughput in the cell. Also certain throughput percentile may be used. In an example embodiment, the throughput indicator is a parameter called avg_Throughput that indicates average throughput in the cell. In some example embodiments, the throughput indicator triggers if it is smaller than a threshold value 15 — 25 Mbit/sec. 450: A diversity mode indicator is compared to its pre-set threshold value. If the indicator does not trigger, the process may stop. MIMO configuration data may be used in conjunction with a diversity mode indicator when checking the triggering of a diversity mode indicator. In an example embodiment, the diversity mode indicator is the MIMO Diversity mode usage. In some example embodiments, the diversity mode indicator triggers if it is smaller than a threshold value 0.7 — 30 %. 460: Responsive to detecting that at least any two of the performance indicators in phases 420, 430, 440, and 450 have triggered, output information indicating that the antenna is operating incorrectly is provided. In an embodiment, output information indicating that the antenna is operating incorrectly is provided responsive to detecting that at least any one of the performance indicators in phases 420, 430, 440, and 450 have triggered. In another embodiment, output information indicating - that the antenna is operating incorrectly is provided responsive to detecting that at

O least any three of the performance indicators in phases 420, 430, 440, and 450 have

N 25 — triggered. In yet another embodiment, output information indicating that the antenna

S is operating incorrectly is provided responsive to detecting that at least any four of z the performance indicators in phases 420, 430, 440, and 450 triggered. In a further e embodiment, output information indicating that the antenna is operating incorrectly 2 is provided responsive to detecting that all of the performance indicators in phases

N 30 420, 430, 440, and 450 have triggered. Phases 420, 430, 440 and 450 may be

N performed in any order on in parallel.

In an embodiment, the thresholds for the HO_ratio, ATT_INTRA_ENB_HO, avg CQI, avg_Throughput, and MIMO Diversity mode usage indicators are 1.0075, 3000, 8, 15 Mbit/sec, and 5 %, respectively. In another embodiment, the thresholds for the HO ratio, ATT INTRA ENB HO, avg CQI, avg_Throughput, and MIMO — Diversity mode usage indicators are 1.025, 8000, 8, 15 Mbit/sec, and 4 %, respectively. In another embodiment, the thresholds for the HO ratio,

ATT INTRA ENB HO, avg CQI, avg Throughput, and MIMO Diversity mode usage indicators are 1.045, 5000, 8, 20 Mbit/sec, and 1.5 %, respectively. In a further embodiment, the thresholds for the HO ratio, ATT INTRA ENB HO, avg COl, avg Throughput, and MIMO Diversity mode usage indicators are 1.045, 4000, 8, 20 Mbit/sec, and 0.7 %, respectively. In yet another embodiment, the thresholds for the HO ratio, ATT INTRA ENB HO, avg CQI, avg Throughput, and MIMO Diversity mode usage indicators are 1.007, 10000, 8, 25 Mbit/sec, and 30 %, respectively.

In some example embodiments, the recognition of incorrectly operating antenna in phase 460 requires that all of the performance indicators trigger, but less stringent threshold values are used for one or more performance indicators. The less stringent threshold values may be used for example for less important performance indicators. In this way, more weight is given for the more important performance indicators.

In some embodiments, the recognition of incorrectly operating antenna in phase 460 requires that at least the throughput indicator and the diversity mode indicator trigger.

O In some embodiments, the recognition of incorrectly operating antenna in phase 460

N 25 requires that at least the throughput indicator, the diversity mode indicator, and the

S handover indicator trigger.

E: In some embodiments, the recognition of incorrectly operating antenna in phase 460

S reguires that at least the throughput indicator, the diversity mode indicator, and the 2 channel quality indicator trigger.

N 30 Insome embodiments, the recognition of incorrectly operating antenna in phase 460 requires that at least the throughput indicator, the diversity mode indicator, handover indicator and the channel quality indicator trigger.

Based on the information provided in phase 460, network operator personnel may then make educated decisions on deployment of maintenance personnel to cells where they are needed.

In an embodiment, the incorrect antenna operation recognized in phase 460 is due to incorrectly coupled cables of a MIMO system.

The method of phases 410-460 provides an automated method for recognizing incorrectly operating antennas of a cellular communication network. In this way, improved network monitoring may be provided. An advantage of the method is that it may be possible to avoid expensive and slow field measurements of antenna operation. Another advantage is that by various example embodiments performance indicator data, that is readily available in the communication networks, can be used for reliably recognizing incorrectly operating antennas. In various embodiments, reliability of recognizing incorrectly operating antennas is improved by looking at a specified combination of at least two performance indicators instead of a single indicator. Reliability may be further increased by looking at a specified combination of at least three or four performance indicators. Yet another advantage is that abnormal situations in a communications network are diminished, and thus, the capacity of the network may be increased.

The process of the method may be manually or automatically triggered. The process may be periodically repeated. The process may be repeated for example once a day, every other day, every three days, once a week, every two weeks, or once a = month. By periodically repeating the process, effective network monitoring is

N achieved and problems, if any, may be timely detected. Additionally or alternatively,

S 25 — the process may be triggered, for example, in response to observing a performance

N problem or degradation in the network or in a particular area or cell. Still further, the

E process may be performed in connection with deployment of new cells or base 0 station site, deployment of new physical equipment in the base station site and/or 3 maintenance actions performed in the base station site. In this way any problems

O 30 with the newly deployed equipment may be detected right away.

Various embodiments have been presented. It should be appreciated that in this document, words comprise, include and contain are each used as open-ended expressions with no intended exclusivity.

The foregoing description has provided by way of non-limiting examples of particular implementations and embodiments a full and informative description of the best mode presently contemplated by the inventors for carrying out the invention. It is however clear to a person skilled in the art that the invention is not restricted to details of the embodiments presented in the foregoing, but that it can be implemented in other embodiments using equivalent means or in different combinations of embodiments without deviating from the characteristics of the invention.

Furthermore, some of the features of the afore-disclosed example embodiments may be used to advantage without the corresponding use of other features. As such, the foregoing description shall be considered as merely illustrative of the principles of the present invention, and not in limitation thereof. Hence, the scope of the invention is only restricted by the appended patent claims.

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Claims (9)

1. A computer implemented method for recognizing an incorrectly connected radio signal cable of an antenna in a cell of a communication network (101), characterized in that the method comprises: obtaining (410) performance indicators of a cell or cells, wherein the performance indicators comprises a handover indicator and/or a channel quality indicator and/or a throughput indicator and/or a diversity mode indicator; comparing the performance indicators (420, 430, 440, 450) to pre-set respective threshold values; providing output information indicating that the antenna is operating incorrectly (460) responsive to detecting that at least any two of the performance indicators have triggered.

2. The method of claim 1, wherein the output information indicating that the antenna is operating incorrectly (460) is provided responsive to detecting that at least any three of the performance indicators have triggered.

3. The method of claim 1, wherein the output information indicating that the antenna is operating incorrectly (460) is provided responsive to detecting that the handover indicator and the channel guality indicator and the throughput indicator and the diversity mode indicator have all triggered.

4 The method of any of the preceding claims, wherein the handover indicator comprises two handover indicators, a first handover indicator indicating handovers within a cell and a second handover indicator indicating handovers between cells, N and wherein the first and second handover indicator values have separate threshold N values. S o 25

5 The method of any one of claims 1-3, wherein the handover indicator 2 comprises a ratio of two handover indicators, a first handover indicator indicating * handovers within a cell and a second handover indicator indicating handovers ; between cells.

O

6. The method of any of the preceding claims, wherein the diversity mode indicator indicates a usage of different layers of a 2x2 or 4x4 MIMO communication system.

7. The method of any of the preceding claims, wherein the diversity mode indicator further comprises MIMO configuration data.

8. An apparatus (20, 111) comprising a processor (21), and a memory (22) including computer program code; the memory and the computer program code configured to, with the processor, cause the apparatus to perform the method of any of the claims 1-7.

9. A computer program comprising computer executable program code (23) which when executed by a processor causes an apparatus to perform the method of any of the claims 1-7. N O N K <Q O N I = O N o LO O QA O N