AU718830B2 - Method and system for testing the condition of a subscriber station in a radio system - Google Patents
Method and system for testing the condition of a subscriber station in a radio system Download PDFInfo
- Publication number
- AU718830B2 AU718830B2 AU20977/97A AU2097797A AU718830B2 AU 718830 B2 AU718830 B2 AU 718830B2 AU 20977/97 A AU20977/97 A AU 20977/97A AU 2097797 A AU2097797 A AU 2097797A AU 718830 B2 AU718830 B2 AU 718830B2
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- AU
- Australia
- Prior art keywords
- testing
- subscriber
- subscriber station
- message
- radio
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W24/00—Supervisory, monitoring or testing arrangements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/24—Testing correct operation
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Mobile Radio Communication Systems (AREA)
- Monitoring And Testing Of Transmission In General (AREA)
- Monitoring And Testing Of Exchanges (AREA)
Description
WO 97/33447 PCTIFI97/00151 Method and system for testing the condition of a subscriber station in a radio system The present invention relates to a method of testing the condition of a subscriber station in a radio system providing a wireless subscriber interface.
The invention further relates to a radio system providing a wireless subscriber interface and comprising a subscriber network element in a data transmission connection with a local exchange of a public telephone network, a base station and subscriber stations, the subscriber network element and said base station comprising means for transfer of telecommunication signals between the local -exchange and the subscriber stations. The invention further relates to a subscriber station in a radio system providing a wireless subscriber interface and consisting of terminal equipment having a radio part, and of a user interface linked to the terminal equipment by means of a two-wire line.
The invention relates to monitoring the operation of a subscriber station used in a WLL system (Wireless subscriber interface), that is, a radio system providing a wireless subscriber interface. In the WLL system, a usual two-wire telephone set is linked by means of special terminal equipment via a radio connection to a local exchange in a telephone network, the exchange in turn being linked to the public telephone network via network cabling. In this connection, a subscriber station refers to the equipment available to a subscriber for transmitting and receiving telecommunication signals, that is, in the case of the WLL system, the subscriber station comprises WLL terminal equipment consisting of a radio part and a teleadapter (to which a user interface, such as a telephone set, is connected), and a user interface, such as a telephone, a telefax terminal, a computer/modem combination or the like, connected to the terminal equipment.
For disturbance-free transfer of telecommunication signals, e.g. signals associated with a call, subscribers stations have to be monitored in the WLL system in order for possible malfunction to be detected as early as possible. Monitoring is very difficult in the WLL system as the WLL terminal is situated on subscriber premises where the operator maintenance personnel have no entry. This is why the condition of a WLL subscriber station has to be monitored via the radio path.
A method of monitoring the operation of a subscriber station in the WLL system is previously known, wherein a call is transmitted to the subscriber station, the call being selected so that the subscriber station answers it automatically. Having answered the call, the subscriber station is diagnosed to WO 97/33447 PCT/FI97/00151 2 be operative. Conversely, if the subscriber station does not answer the call, the call is repeated until the subscriber station has failed to answer a predetermined number of calls, and consequently the subscriber station is diagnosed to be inoperative.
The most significant weakness of the above known method is that the only information conveyed on the subscriber station is that the WLL subscriber station answers a call received via the radio path. This information is not sufficient for the operator to, e.g. by maintenance or the like, prevent disturbance, or alternatively, deal with temporary disturbances before the user of the subscriber station detects the disturbance.
It is an object of the present invention to solve the above problem and provide a better and more versatile method of monitoring the operation of subscriber stations in order to detect possible malfunction as early as possible, even before the user of the subscriber station detects the disturbance. These goals are achieved with the method of the invention, characterized in that a subscriber station is equipped with testing means for execution of tests indicative of the condition of the subscriber station, a predetermined testing message is transmitted via the radio path to the testing means of the subscriber station when no connection is active from the subscriber station, the testing message containing information indicating the test to be carried out, and a message indicative of the results of the test carried out is received from the subscriber station via the radio path.
The invention is based on the idea that it is significantly easier to test the condition of a subscriber station when subscriber stations are equipped with special test units by means of which the subscriber units can independently carry out given test measurements, and transmit information indicative of the results of the test to the operator as a response to a received testing message. Consequently the operator can, whenever desirable, e.g.
daily at a predetermined time of the day, start a test sequence for testing the condition of the subscriber stations in the system. The most significant advantages of the method of the invention are that it offers the operator a chance to monitor the condition of e.g. a given subscriber station without any participation of the user of said subscriber station or even any awareness that his/her subscriber station is being tested, the reliability of the system being significantly improved, and that the operator can control the testing means so that they will carry out a given test on the basis of information included in the test- WO 97/33447 PCTFI97/00151 3 ing message, and hence all tests do not have to be carried out at the same time, but can be done periodically e.g. so that a single subscriber station will be completely tested during one week (that is, e.g. one test/day), which will shorten the time needed for testing a large number of subscriber stations.
The invention further relates to a system to which the method of the invention can be applied. The system of the invention is characterized in that the system comprises a subscriber station with testing means for testing the condition of the subscriber station as a response to a testing message transmitted from the subscriber network element via the radio path, the information in said testing message indicating to the testing means the test to be carried out, and means for transmitting a message indicative of the results of the test to the subscriber network element via the radio path, and that the subscriber network element comprises means for transmitting said testing message at a time specified by the operator, and means for receiving a message indicative of the results of the test from the subscriber station, and for forwarding the information indicative of said results to the operator. Thus the system of the invention provides the operator with a better chance than before to monitor the operation of separate subscriber stations centralized, e.g. from a network management centre.
In a preferred embodiment of the system of the invention, the testing means of the subscriber station comprise means for measuring the signal level of a received signal, and for transmitting a message indicative of the measuring result via the subscriber network element further to the operator.
This embodiment of the invention allows the operator to receive information on the field strength as seen by the subscriber station and to conclude from this information if e.g. problems of a malfunctioning subscriber station are due to a weak field strength, i.e. the fact that the subscriber station is e.g. incorrectly placed. In this case the operator can contact the user of the subscriber station and tell him/her to transfer the subscriber station to another place where the field strength is likely to be better, or alternatively, by reconfiguration, to transfer the subscriber station to an adjacent base station. Furthermore, as the testing message and the message indicative of the results of the test are transmitted on the control channel of the system, execution of the test speeds up as no traffic channel has to be assigned to the subscriber station during the test, but all information relevant to the test can be transmitted on the control channel between the subscriber network element and the subscriber station by 4 b -4utilizing system call frames.
In another preferred embodiment of the invention, signalling between a subscriber station and a subscriber network element is essentially similar to that defined in NMT-900 specifications, the subscriber network element being arranged to use frame la, la', la" or lb defined in NMT-900 specifications point 4.3.2.1 as a testing message, and the subscriber station is arranged to transfer the message indicative of the test results to the subscriber network element by frame 10a or 10Od defined in NMT-900 specifications point 4.3.2.2. This embodiment of the invention provides a chance to apply the method of the invention to the WLL system based on the NMT-900 mobile communication system, the signalling of the subscriber station and the subscriber network element associated with testing a subscriber station being formed such that subscriber stations of the NMT-900 system can also be utilized in the system. This means that although all aspects of the signalling of the subscriber network element are not similar to 15 the signalling defined in the NMT-900 specifications, the differences are, however, insignificant as regards the operation of a conventional NMT-900 mobile station, and consequently do not cause disturbance.
The invention further relates to a subscriber station for applying the method of the invention, and which can be used in the system of the invention. The subscriber 20 station of the invention is characterized in that the terminal equipment comprises testing means for testing the condition of the subscriber station as a response to a testing message transmitted to the subscriber station via the radio path, the information in said testing message indicating to the testing means the test to be performed, and means for transmitting a message indicative of the test results via the radio path to other parts of the 25 system. Thus the subscriber station of the invention allows the operator to monitor its operation via the radio path without the user of the subscriber station having to participate in or be aware of the monitoring.
The preferred embodiments of the method, system and subscriber station of the invention are disclosed in the attached dependent claims 2 to 3, 5 to 7, and 9.
In the following the invention will be described in greater detail by means of a preferred embodiment of the invention with reference to the accompanying drawings, in which Figure 1 shows a block diagram of a first preferred embodiment of [R:\LIBQ]00146.doc:GMM WO 97/33447 PCT/FI97/00151 the system of the invention, and Figures 2A and 2B illustrate signalling frames utilized in the method of the invention.
Figure 1 shows a block diagram of a first preferred embodiment of the radio system of the invention. Figure 1 shows the part of the WLL system to which the method of the invention can be applied. The WLL system shown in Figure 1 is based on the NMT-900 system (Nordisk Mobil Telefon), simplified by irrelevant properties having been omitted. Base stations 5 are similar to parts of the NMT-900 cellular radio system. This means that signalling between a subscriber station 1 and the base stations is quite similar to the signalling between a subscriber station and a base station in the NMT-900 mobile communication system. Consequently, calls to a conventional NMT-900 system mobile station 9 can also be forwarded via the base stations 5 and a subscriber network element 6, provided that the operator has programmed the subscriber network element 6 for forwarding calls regarding said telephone.
The subscriber station 1 shown in Figure 1 consists of a user interface, i.e. a telephone set 2, and terminal equipment 3. The telephone set 2 shown in Figure 1 can be a conventional voice-frequency telephone set connectable to a fixed telephone network. A two-wire line 4, via which signals can be transferred between the terminal equipment and the telephone set connects the telephone set 2 and the terminal equipment 3. The terminal equipment 3 comprises signal processing means for adapting a speech path to a radio channel. Such signal processing means include e.g. a radio part 11 comprising an antenna 8, a radio transmitter and a radio receiver, and a teleadapter 10 for fitting the radio part to a conventional telephone set 2.
The subscriber station 1 uses radio frequency signals to communicate via the antenna 8 with the base station 5 (the Figure shows three base stations BS) via which calls are forwarded to the subscriber network element 6 and further to an exchange 7 in a PSTN network (Public Switched Telephone Network), i.e. a fixed telephone network. In the case of Figure 1, the subscriber network element 6 can be linked to the local exchange of a fixed telephone network via e.g. an open multiplexer interface of type CCITT Q.512 V2 or V5.1 or V5.2 using a 2 Mbit/s PCM system (Pulse Code Modulation).
The subscriber network element 6 shown in Figure 1 is quite similar to the MTX exchange in the NMT-900 system except that properties irrelevant to the WLL system have been omitted, such as operations associated with WO 97133447 PCT/FI97/00151 6 handover not needed in the WLL system.
In accordance with the invention, the terminal equipment 3 of the subscriber station 1 comprises a measuring unit 13 with means for testing the condition of the subscriber station using a plurality of optional tests. Consequently the measuring unit 13 is able to monitor the condition of the subscriber station 1 by measuring e.g. the signal level of a signal received via the radio path. The measuring unit 13 further comprises means for e.g. testing the condition of the user interface 2 by means of current, voltage and insulation resistance measurements performed on the two-wire line 4. By means of these tests the terminal equipment also finds out if a user interface 2 is at all linked to it, or if the user has unplugged the telephone from the terminal equipment 3.
The measuring unit 13 preferably also comprises a memory for recording data regarding disturbances in the operation of the terminal equipment. The data is stored in the memory until a testing message is forwarded to the subscriber station from the subscriber network element 6, leading to release of the data for the use of the operator.
In accordance with the invention, the operator may activate, e.g.
from a network management centre by remote control, a test sequence in which the subscriber network element 6 goes through every system subscriber station one at a time, and performs one or more tests on them. Such a test sequence may start e.g. automatically daily at a given time. The testing time is preferably chosen so that during the testing the system loading level is low (a small number of calls in progress).
Figures 2A and 2B illustrate the signalling frames utilized in the method of the invention and in the system of Figure 1.
To test the condition of the subscriber station 1 of Figure 1, the subscriber network element 6 transmits a testing message S1 via a base station to the subscriber station 1 on a control channel. A frame la, la', la" or lb defined in the NMT-900 specifications point 4.3.2.1 (NMT Doc 900-1, January 29, 1985) is preferably used as the testing message. Figure 2A illustrates frame la (Calling Channel Indication, General). In accordance with this embodiment, variable Z is always assigned the value 0, whereas the test desired is denoted by values of the variables Al to A3.
After performing the desired test, the subscriber station forwards information on the measuring result to the subscriber network element by using message S2, preferably frame 10a or 10d defined in the NMT-900 specifi- WO 97/33447 PCT/FI97/00151 7 cations point 4.3.2.2. Figure 2B illustrates frame 10a (Call acknowledgement from MS on calling channel, and access on access channel). In accordance with this embodiment (and as distinct from the NMT-900 specifications) said frame is transmitted in full. The information indicative of the test results is forwarded via variables Al to A4.
When a testing message S1, in which variable Al has been assigned the value 1, is forwarded to the testing means 13, the measuring unit performs a test to see if a user interface is linked to the terminal equipment and if malfunction has occurred in the subscriber station. After the tests, information on the results is forwarded via the subscriber network element to the operator by message S2, i.e. by transmission of the frame of Figure 2B, variable Al being assigned the value 1, and the bits (A2=bOblb2b3b4b5b6b7b8, A3=bOblb2b3b4b5b6b7b8 and A4=bOblb2b3b4b5b6b7b8) of variables A2 to A4 being coded on the basis of the results e.g. so that in variable A2: bit bO=l user interface linked bit bl=1 error condition 1 in terminal bit b2=1 error condition 2 in terminal bit b8=l error condition 8 in terminal.
Similarly, when a testing message S1, i.e. the frame of Figure 2A, in which variable Al has been assigned the value 2, is forwarded to the testing means 13, the measuring unit 13 measures the signal level of the received signal. The measuring unit 13 forwards the measurement result to the subscriber network element by message S2, where variable A1=2, and variables A2 and A3 are assigned values depicting a measured dBm value in hexadecimals (negative), that is, e.g. -91 dBm 5B (in hexadecimals) and -112 dBm 70 (in hexadecimals).
It will be appreciated that the above description and the accompanying drawings are presented by way of illustration only. It will be understood by those skilled in the art that various modifications and changes may be made without departing from the spirit and scope of the invention disclosed in the appended claims.
Claims (10)
1. A method of testing the condition of a subscriber station in a radio system providing a wireless subscriber interface, wherein a subscriber station is equipped with testing means for execution of tests indicative of the condition of the subscriber station, the method comprising the steps of: transmitting a predetermined testing message via the radio path to the testing means of the subscriber station when no connection is active from the subscriber station, the testing message containing information indicating the test to be carried out, io and receiving a message indicative of the results of the test carried out from the 0 6 subscriber station via the radio path.
2. A method as claimed in claim 1, whereby the testing means comprise 0S-. 15 means for measuring the signal strength of a received signal.
3. A method as claimed in claim 1, whereby the subscriber station consists of terminal equipment having a radio part, and of a user interface linked to the Sterminal equipment by means of a two-wire line, the testing means in the terminal 20 equipment comprising means for testing of the condition of the user interface by means gig• of current, voltage and insulation resistance measurements. OOOOO
4. A radio system providing a wireless subscriber interface and comprising a subscriber network element in a data transmission connection with a local exchange of a public telephone network, a base station and subscriber stations, the subscriber network element and said base station comprising means for transfer of telecommunication signals between the local exchange and the subscriber stations, wherein: IN:\LIBK]O1059:MXL the system comprises a subscriber station with testing means for testing the condition of the subscriber station as a response to a testing message transmitted from the subscriber network element via the radio path, the information in said testing message indicating to the testing means the test to be carried out, and means for transmitting a message indicative of the results of the test to the subscriber network element via the radio path, and the subscriber network element comprises means for transmitting said testing message at a time specified by the operator, and means for receiving a message indicative of the results of the test from the subscriber station, and for forwarding the information indicative of said results to the operator.
5. A system as claimed in claim 4, wherein the testing means of the *0 subscriber station comprise: Oe .0 •means for measuring the signal level of a received signal and/or means for 15 "•testing the condition of the user interface by means of current, voltage and insulation resistance measurements performed on the two-wire line.
6. A system as claimed in claim 4, wherein the subscriber network element is arranged to transmit the testing message to the subscriber station on a system control channel, and that the subscriber station is arranged to forward said message indicative of the results of the test to the subscriber network element on a control channel. S7. A system as claimed in claim 4, wherein signalling between a subscriber station and a subscriber network element is essentially similar to that defined in NMT-900 specifications, the subscriber network element being arranged to use frame la, la', la" or lb defined in NMT-900 specifications point 4.3.2.1 as a testing message, and the subscriber station is arranged to transfer the message indicative of the [N:\LIBKIO1059:MXL test results to the subscriber network element by frame 10a or 10d defined in NMT-900 specifications point 4.3.2.2.
8. A subscriber station in a radio system providing a wireless subscriber interface and consisting of terminal equipment with a radio part, and of a user interface linked to the terminal equipment by means of a two-wire line, wherein the terminal equipment comprises: testing means for testing of the condition of the subscriber station as a response to a testing message transmitted to the subscriber- station via the radio path, the information in said testing message indicating the test to be carried out, and means for transmitting a message indicative of the test results via the radio °path to other parts of the system. r
9. A subscriber station as claimed in claim 8, wherein the testing means 15 comprise means for measuring the signal level of a received signal and/or means for testing the condition of a user interface by means of current, voltage and insulation resistance measurements performed on the two-wire line. .C A method of testing the condition of a subscriber station in a radio 20 system, substantially as described herein with reference to the accompanying drawings.
11. A radio system, substantially as described herein with reference to the accompanying drawings.
12. A subscriber station, substantially as described herein with reference to the accompanying drawings. DATED this Sixth Day of October 1998 Nokia Telecommunications OY RPatent Attorneys for the Applicant SPRUSON FERGUSON [N:\LIBKI01059:MXL
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI961074A FI103167B1 (en) | 1996-03-07 | 1996-03-07 | Method of checking the fitness of a subscriber device |
| FI961074 | 1996-03-07 | ||
| PCT/FI1997/000151 WO1997033447A1 (en) | 1996-03-07 | 1997-03-06 | Method and system for testing the condition of a subscriber station in a radio system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| AU2097797A AU2097797A (en) | 1997-09-22 |
| AU718830B2 true AU718830B2 (en) | 2000-04-20 |
Family
ID=8545603
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU20977/97A Ceased AU718830B2 (en) | 1996-03-07 | 1997-03-06 | Method and system for testing the condition of a subscriber station in a radio system |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP0878107A1 (en) |
| JP (1) | JP2000506337A (en) |
| CN (1) | CN1212817A (en) |
| AU (1) | AU718830B2 (en) |
| BR (1) | BR9707847A (en) |
| CA (1) | CA2248151A1 (en) |
| FI (1) | FI103167B1 (en) |
| WO (1) | WO1997033447A1 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1045601A1 (en) * | 1999-04-14 | 2000-10-18 | Ascom AG | Measuring the service quality in communication networks |
| FR2796787A1 (en) * | 1999-07-21 | 2001-01-26 | Alstom | INFORMATION EXCHANGE SYSTEM BETWEEN A MASTER STATION AND DIFFERENT SLAVE STATIONS CONNECTED BY A RADIO-ELECTRIC INFORMATION TRANSMISSION NETWORK |
| DE10028029A1 (en) * | 2000-06-08 | 2001-12-20 | Acterna Muenchen Gmbh | Text message transmission capability testing method for mobile radio device uses testing device providing test text message transmitted to mobile radio device |
| EP1239688A1 (en) * | 2001-03-08 | 2002-09-11 | Sony International (Europe) GmbH | Mobile telecommunication means comprising means for detecting and reporting errors |
| GB2381159B (en) * | 2001-10-17 | 2004-02-18 | Motorola Inc | Transceivers and method for use in radio communications |
| US7339891B2 (en) * | 2002-01-09 | 2008-03-04 | Mverify Corporation | Method and system for evaluating wireless applications |
| KR102072176B1 (en) * | 2013-08-26 | 2020-01-31 | 에스케이플래닛 주식회사 | Service providing device for transferring push/target message, push/target message transfer system comprising the same, control method thereof and computer readable medium having computer program recorded therefor |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1995009512A1 (en) * | 1993-09-27 | 1995-04-06 | Nokia Telecommunications Oy | Radio system and a subscriber terminal for a radio system |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4449246A (en) * | 1980-05-02 | 1984-05-15 | Harris Corporation | Orderwire communication system |
| IT1252125B (en) * | 1991-10-23 | 1995-06-05 | Sgs Thomson Microelectronics | METHOD AND CIRCUIT DEVICE FOR MEASURING OPERATING PARAMETERS OF AN INTERFACE CIRCUIT AND A USER TELEPHONE LINE CONNECTED TO THEM IN OPERATING CONDITIONS |
| US5603093A (en) * | 1994-12-28 | 1997-02-11 | Ntt Mobile Communications Network, Inc. | Method for monitoring the state of interference by a base station of a mobile radio communication system |
-
1996
- 1996-03-07 FI FI961074A patent/FI103167B1/en active
-
1997
- 1997-03-06 WO PCT/FI1997/000151 patent/WO1997033447A1/en not_active Application Discontinuation
- 1997-03-06 JP JP9531498A patent/JP2000506337A/en active Pending
- 1997-03-06 CA CA002248151A patent/CA2248151A1/en not_active Abandoned
- 1997-03-06 AU AU20977/97A patent/AU718830B2/en not_active Ceased
- 1997-03-06 EP EP97906206A patent/EP0878107A1/en not_active Withdrawn
- 1997-03-06 CN CN 97192829 patent/CN1212817A/en active Pending
- 1997-03-06 BR BR9707847A patent/BR9707847A/en not_active Application Discontinuation
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1995009512A1 (en) * | 1993-09-27 | 1995-04-06 | Nokia Telecommunications Oy | Radio system and a subscriber terminal for a radio system |
Also Published As
| Publication number | Publication date |
|---|---|
| BR9707847A (en) | 1999-07-27 |
| FI103167B (en) | 1999-04-30 |
| EP0878107A1 (en) | 1998-11-18 |
| WO1997033447A1 (en) | 1997-09-12 |
| CN1212817A (en) | 1999-03-31 |
| AU2097797A (en) | 1997-09-22 |
| FI103167B1 (en) | 1999-04-30 |
| FI961074A0 (en) | 1996-03-07 |
| JP2000506337A (en) | 2000-05-23 |
| CA2248151A1 (en) | 1997-09-12 |
| FI961074A (en) | 1997-09-08 |
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Legal Events
| Date | Code | Title | Description |
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| FGA | Letters patent sealed or granted (standard patent) | ||
| MK14 | Patent ceased section 143(a) (annual fees not paid) or expired |