WO1999053709A2

WO1999053709A2 - Procedure and system for utilisation of radio link measurement data

Info

Publication number: WO1999053709A2
Application number: PCT/FI1999/000292
Authority: WO
Inventors: Petri Saarela; Jaakko Rautiainen; Timo Kononen; Esko Luttinen
Original assignee: Nokia Networks Oy
Priority date: 1998-04-08
Filing date: 1999-04-07
Publication date: 1999-10-21
Also published as: FI980808A0; AU3422099A; WO1999053709A3; FI106237B; FI980808A; EP1070433A2

Abstract

Procedure and system for utilisation of radio link measurement data in a telecommunication network comprising a local exchange (LE), an access node (AN) connected to the local exchange, a wireless communication system (20) comprising a base station (BS) and connected to the access node, and a terminal (MS) which communicates with the access node (AN) over the wireless communication system. In the procedure, the quality of the radio link between the terminal and the base station is measured by the terminal in the base-station-to-terminal (downlink) direction and by the base station in the terminal-to-base-station (uplink) direction. According to the invention, the measurement data for the uplink direction measured by the base station are transmitted to the terminal and the measurement data are presented to the user of the terminal, the A-subscriber, in conjunction with installation and/or a monitoring action during use.

Description

PROCEDURE AND SYSTEM FOR UTILISATION OF RADIO LINK MEASUREMENT DATA

The present invention relates to telecommunication. In particular, the present invention relates to a new type of procedure and system for the utilisation of measurement data for downlink and uplink directions in the installation of a wireless system and in the monitoring of its operational condition during use . In a wireless local loop ( LL) , a terminal is connected over a radio link to an access node or a WLL controller. The access node may consist of multiplexers, cross-connection devices and various transmission systems. A WLL system may be based e.g. on a technol- ogy used in mobile communication systems, such as the GSM/DCS1800 technology (GSM, Global System for Mobile Communications; DCS, Digital Cellular System) . GSM is a European digital mobile communication system standardised by ETSI. DCS-1800 is a mobile communication system based on the GSM specification and standardised by ETSI, which aims at a more efficient use of micro- cells and which works in a 1800 MHz frequency range. Other mobile communication technologies may also be used. Between the terminal and the access node there is a base station, which transmits the call signals received from the terminal over a radio channel to the access node and further to the public telephone network and vice versa. The access node or WLL con- troller may be connected to the telephone exchange using e.g. a V5.1 or V5.2 interface.

The serviceability of a WLL terminal is heavily dependent on the quality of the radio link between the terminal and the base station, and it may also be influenced by the condition and quality of the transmission link between the base station and the access node. In current solutions, it is not possible to gather this information in a single point, i.e. in the first place a terminal being installed or already in use, so as to make the information available to the installer or for monitoring during use. For radiotelephonic reasons, it is necessary to be able to determine the best location and orientation for the placement of a WLL terminal or its external antenna on the basis of radio link quality data, by using the strength of the signal sent from the base station to the terminal (downlink) and the signal sent from the terminal to the base station (uplink) . Moreover, it must be possible to check the quality of the radio link even in conjunction with normal use after installation. At present, radio link quality information for the downlink direction is available directly from the terminal as it measures the downlink part of the connection itself. However, for the uplink direction, radio link quality information can only be obtained from measurements carried out by the base station, so it is not available at the place of installation or in conjunction with monitoring during use like the information for the downlink direction.

Since the transmission link between the ter- minal , base station and access node and its condition naturally have an effect on the serviceability of the terminal, optimisation of link quality is of primary importance .

The object of the present invention is to improve the availability of measurement data for purposes of installation and monitoring during use and at the same time to eliminate or at least significantly reduce the drawbacks described above .

A specific object of the present invention is to disclose a new type of procedure and system which provide information for an installer about a radio link when installing a terminal or performing mainte- nance operations on one. A further object of the invention is to disclose a system for improving customer service when the user himself is carrying out monitoring actions during use so that the operator can par- ticipate in the interpreting of indications of radio link quality.

As for the features characteristic of the present invention, reference is made to the claims.

The procedure of the invention relates to a procedure for utilising radio link measurement data in a telecommunication system. The telecommunication system preferably comprises a local exchange, an access node connected to the local exchange, a wireless communication system comprising a base station and con- nected to the access node. Moreover, the telecommunication system comprises a terminal which communicates with the access node over the wireless communication system. In the procedure, the quality of the radio link between the terminal and the base station is measured by the terminal in the base station-to- terminal (downlink) direction and by the base station in the terminal-to-base station (uplink) direction.

The interface between the local exchange and the access node may be implemented using e.g. a V5.1 or V5.2 interface. These interfaces are defined in the ETS 300 324 and ETS 300 347 standard series, respectively.

According to the invention, measurement data measured by the base station from the signal sent by the terminal are transmitted to the terminal, and the measurement data received by the terminal are presented to the user of the terminal, here called the A- subscriber, in conjunction with installation or a monitoring action during use. The measurement data may be transmitted to the terminal e.g. in the form of GSM signalling. In this case, the information could be transferred using cc-layer messages consistent with GSM specification 04.08; reference is made to the specification GSM 04.08 9.3.31 USER INFORMATION. The measurement data received by the terminal could be presented to the subscriber using signal tones or vis- ual signals, e.g. signal lights.

As compared with prior art, the present invention has the advantage that the system makes it easier to find the right place for a terminal to be installed for a subscriber. Moreover, the invention allows the user to verify correct placement of the terminal on the basis of the strengths of signals sent in both directions. In addition, the invention allows communication problems appearing during use to be more easily analysed by both the subscriber and the opera- tor. Furthermore, the subscriber and the operator can simultaneously have a speech connection between them and thus discuss the placement of the terminal .

Further, the invention is a definite improvement with respect to the traditional GSM system (which generally is the basis of WLL solutions) , because in the GSM system there is no definition for transmission of measurement data for the uplink direction to the terminal .

The measurement data can preferably be trans- mitted as signal tones either to the A-subscriber or to the A-subscriber and the B-subscriber in conjunction with installation or a monitoring action during use. The transmission of measurement data to the A- subscriber can be activated by calling a first prede- termined subscriber number, a so-called test number. This initiates a link quality check extending from the subscriber terminal to the local exchange. Correspondingly, the transmission of measurement data to the A- subscriber and the B-subscriber is activated by call- ing a second predetermined subscriber number. At the same time, the quality of the whole link can be checked. When the access node detects that the subscriber's dialling leads to a test number and may already have set up a connection with the local exchange, then the call is cleared and conversion of the radio link measurement data into signal tones and their transmission to the A-subscriber are activated. This is done when the subscriber calls the first predetermined test number. If the subscriber calls the second predetermined test number, then the call is set up in the normal manner to the B-subscriber. When the access node detected that the called number was the second test number, it activated the conversion of measurement data into signal tones and their transmission to the A and B subscribers. The B-subscriber may be e.g. an operator service number, in which case a representative of the operator or an automatic device can listen to the signal tones indicative of link quality over the same voice connection with the customer and thus discuss actions that the customer can take to improve the quality of the link.

In addition, the transmission of the customer's dialling from the terminal to the access node and further to the local exchange can preferably be implemented in two ways. In non-transparent connection setup, the call is started from the terminal in such manner that the entire dialling is transmitted in a message frame between the base station and the terminal. The access node receives the dialling from the message frame and, if it is a number reserved for the purpose of checking link quality and sending measurement data to the A-subscriber, then the measurement data conversion and transmission of the data to the A- subscriber are activated. The call is not connected from the access node to the local exchange. Corre- spondingly, when the called number is the second predetermined test number, a connection to the B- subscriber is set up and the measurement data are con- verted into signal tones, which are sent to the A and B subscribers.

In transparent call setup, the call is started from the terminal so that the dialling is transmitted to the local exchange while the terminal and the access node have a voice connection between them. In this case, the access node interprets the dialling originated from the terminal digit by digit. When the access node detects that the number is a test number reserved for the purpose of checking link quality and transmitting measurement data to the A- subscriber, the access nodes activates the conversion of measurement data into signal tones and their transmission to the A-subscriber. The call is not connected from the access node to the local exchange. If the access node detects that signal tones have to be transmitted to the B-subscriber as well, then a connection with the B-subscriber is set up and the signal tones are transmitted to the B-subscriber, too. The present invention also relates to a system for utilisation of radio link measurement data in a telecommunication network. As for the telecommunication network, we refer to the preferred telecommunication network described above in conjunction with the procedure of the invention. The system of the invention comprises means for measuring the quality of a radio link between a terminal and a base station in the base station-to-terminal direction and means for measuring radio link quality in the terminal-to-base station direction.

According to the invention, the system comprises means for transmitting the measurement data for the uplink direction measured by the base station to the terminal and means for presenting the measurement data to the user of the terminal, the A-subscriber, in conjunction with installation or a monitoring action during use. The means for presenting the measurement data are preferably implemented using a buzzer or a light-emitting diode. Other implementations can also be used.

As for the advantages of the system of the invention, we refer to the advantages of the procedure presented above.

In a preferred embodiment of the system of the invention, the system comprises means for transmitting signal tones to the called party, the B- subscriber, as well. Thus, the B-subscriber, which may be e.g. the operator, gets important information about the quality of the link in the uplink direction.

The system preferably also comprises means for activating a function for the transmission of measurement data to the A-subscriber when the A- subscriber calls a first predetermined subscriber number. Correspondingly, the system comprises means for activating a function for the transmission of measurement data to the A-subscriber and the B-subscriber when the subscriber calls a second predetermined subscriber number.

In a preferred embodiment, the system comprises means for monitoring the measurement data at the B-subscriber ' s subscriber interface and for giving instructions regarding placement of the terminal and other technical matters relating to radiotelephony to the user of the terminal over the telecommunication network. The called party's subscriber interface may also be manned by a physical person who is a represen- tative of the operator. Thus, the operator's representative and the user of the terminal can discuss the positioning of the terminal.

The system of the invention preferably also comprises means for terminating normal call setup when the A-subscriber ' s dialling leads to the first or the second predetermined subscriber number. The system preferably also comprises means for adding the entire dialling information to a message frame and means for transmitting the dialling information to the local exchange while a voice connection exists between the terminal and the access node. The method of transmit- ting the dialling information is selected separately for each case .

In the following, the invention will be described by the aid of a few preferred examples by referring to the attached drawing, wherein Fig. 1 presents a preferred telecommunication system according to the invention; and

Fig. 2 presents a flow diagram representing a preferred embodiment of the present invention.

The system presented in Fig. 1 comprises a local exchange LE and an access node AN connected to it via a V5 interface. A terminal MS communicates with the access node over a wireless communication system 20. In addition, as an example, another terminal, the B-subscriber ' s terminal, indicated by arrow B, is con- nected to the local exchange. Thus, the wireless communication system in this example consists of a base station BS and a terminal MS communicating with it over a radio link. The connection between the terminal and the local exchange is set up transparently so that the operation of the terminal mainly corresponds to the operation of an ordinary telephone connected to a wired telephone network.

The terminal is provided with means 4 for giving signal tones to the subscriber on the basis of radio link quality information obtained from the access node or the base station. When the access node AN knows the measurement results, it can use its own signal tone generator to generate suitable signal tones and transmit them to the terminal. E.g. a quality scale of grades 1-5 could be represented by signal tones 1-5, so the subscriber would hear from the ter- minal a given signal tone sequence corresponding to the quality of the link.

Moreover, the terminal device is provided with means 10 for adding the entire dialling informa- tion to a message frame. In themselves, these means 10 are part of conventional mobile telephone technology and known e.g. from the GSM system.

The base station comprises means 2 for measuring the signals received from the terminal, on the basis of which it is possible to judge the quality of the radio link from the terminal MS to the base station BS . These means 2 can be implemented using the standard base station property defined in GSM standard 05.08. Implemented in the access node are means 3 for transmitting the measurement data to the terminal. The means 3 for transmitting measurement data may also be implemented in the base station. In addition, the access node comprises means 5 for transmitting signal tones to the called party, the B-subscriber. The implementation of means 3 and 5 may be identical with means 4. If the means 3 for transmitting measurement data are disposed in the base station, then the means 5 for transmitting signal tones to the called party are connected to the base station to allow measurement data to be obtained. Moreover, the access node comprises means 6, 7 for monitoring the dialling given by the subscriber. Based on the dialling, if it is detected that the subscriber is calling a first or a second predetermined test number, transmission of measurement data to the A-subscriber, or to the A- subscriber and B-subscriber, is activated. These means 6, 7 can be implemented as suitable program blocks in the access node AN. Using means 9, normal call setup is terminated in the access node AN and the transmission function is activated. In this situation, the call setup procedure is not completed, i.e. the call is not connected over the V5 interface to the local exchange LE. The dialling stops at the access node AN, which is located between the subscriber/base station and the lo- cal exchange. If the subscriber's dialling information is to be transmitted via the voice connection between the terminal MS and the access node AN, then this is implemented using means 11 disposed in the access node. This is implemented as normal call setup. The B-subscriber ' s terminal B connected to the local exchange LE comprises means 8 for monitoring the measurement data and giving instructions to the A- subscriber. The monitoring and the giving of instructions can be implemented as automatic functions, or the function of means 8 can be performed by a physical person over a voice connection with the user of the terminal MS .

Referring to Fig. 2, a simple and advantageous embodiment of the procedure of the present in- vention will now be presented. First, the subscriber enters a dialling, calling the first or the second predetermined subscriber number, block 21. In the access node AN, a check is carried out to establish whether the measurement data are to be transmitted to A or to A and B, block 22. If the call is addressed to a predetermined subscriber number, then the procedure goes on to block 24 and actual call setup to the local exchange is terminated. After that, transmission of measurement data to the A-subscriber ' s terminal MS is activated, block 25. In the access node AN, the measurement data are converted to signal tones and transmitted to the A-subscriber, blocks 26 and 27. When the subscriber hangs up, the transmission of measurement data is stopped. In a corresponding manner, the procedure goes on from block 22 to block 28 if it is detected that the A-subscriber is calling the second predetermined subscriber number. After that, call setup to the B- subscriber is continued, block 28. After the connection has been established, the procedure goes on to block 29 and transmission of measurement data to the A-subscriber and the B-subscriber is activated. Further, the measurement data are converted to signal tones, which are transmitted to both subscribers, blocks 29 and 30. As above, the transmission of measurement data is stopped when the subscriber hangs up. The invention is not restricted to the examples of its embodiments described above, but many variations are possible within the scope of the inventive idea defined by the claims.

Claims

1. Procedure for utilisation of radio link measurement data in a telecommunication network comprising a local exchange (LE) , an access node (AN) connected to the local exchange, a wireless communication system (20) comprising a base station (BS) and connected to the access node, and a terminal (MS) which communicates with the access node (AN) over the wireless communication system, in which procedure the quality of the radio link between the terminal and the base station is measured by the terminal in the base- station-to-terminal (downlink) direction and by the base station in the terminal-to-base-station (uplink) direction, characterised in that the measurement data for the uplink direction measured by the base station are transmitted to the terminal ; and the measurement data are presented to the user of the terminal, the A-subscriber, in conjunction with installation and/or a monitoring action during use.

2. Procedure as defined in claim 1, characterised in that the measurement data are transmitted to the called party, the B-subscriber.

3. Procedure as defined in claim 1 or 2, characterised in that the measurement data are transmitted in the form of signal tones and/or visual signals, such as signal lights.

4. Procedure as defined in any one of claims 1 - 3, characteri sed in that the function for the transmission of measurement data to the A- subscriber is activated by calling a first predetermined subscriber number.

5. Procedure as defined in any one of claims 1 - 3, characteri sed in that the function for the transmission of measurement data to the A- subscriber and the B-subscriber is activated by calling a second predetermined subscriber number.

6. Procedure as defined in any one of claims 1 - 5, characte i sed in that the measurement data are monitored at the called party's subscriber interface and, based on this monitoring, the user of the terminal is given instructions concerning placement of the terminal and other technical matters relating to radiotelephony.

7. Procedure as defined in any one of claims 1 - 6, characterised in that normal call setup is terminated and the transmission function is activated when it is detected that the A-subscriber is dialling a subscriber number intended for activation of a measurement data transmission function.

8. Procedure as defined in any one of claims 1 - 7, characterised in that a call from the terminal to the first or second predetermined subscriber number is started by transmitting the entire dialling information in a message frame sent between the base station and the terminal.

9. Procedure as defined in any one of claims

1 - 7, characteri sed in that a call from the terminal to the first or second predetermined subscriber number is started by transmitting the dialling information while the terminal and the access node have a voice connection with the local exchange.

10. System for utilisation of radio link measurement data in a telecommunication network comprising a local exchange (LE) , an access node (AN) connected to the local exchange, a wireless communica- tion system (20) comprising a base station (BS) and connected to the access node, and a terminal (MS) which communicates with the access node (AN) via the wireless communication system, said system comprising means (1) for measuring the quality of the radio link between the terminal and the base station in the base- station-to-terminal (downlink) direction and means (2) for measuring the quality of the radio link in the termmal-to-base-station (uplink) direction, char acteri sed in that the system comprises means (3) for transmitting the measurement data for the uplink direction measured by the base station to the terminal; and means (4) for presenting the measurement data to the user of the terminal, the A-subscriber, in conjunction with installation and/or a monitoring action during use .

11. System as defined in claim 10, char acteri sed in that the system comprises means (5) for transmitting signal tones to the called party, the B-subscriber.

12. System as defined in claim 10 or 11, characterised in that the system comprises means (6) for activating the transmission of measurement data to the A-subscriber by calling a first predetermined subscriber number.

13. System as defined in any one of claims 10 - 12, characterised in that the system comprises means (7) for activating the transmission of measurement data to the A-subscriber and the B- subscriber by calling a second predetermined subscriber number.

14. System as defined in any one of claims 10

- 13, characterised in that the system comprises means (8) for monitoring the measurement data at the called party's subscriber interface and for giving the user of the terminal instructions concern- ing placement of the terminal and other technical matters relating to radiotelephony, based on the monitoring.

15. System as defined in any one of claims 10 14, characteri sed in that it comprises means (9) for terminating the normal call setup process and activating a transmission function when it is detected in the access node (AN) that the A-subscriber is dialling a subscriber number intended for activation of a measurement data transmission function.

16. System as defined in any one of claims 10

- 15, characteri sed in that the system com- prises means (10) for adding the entire dialling information to a message frame.

17. System as defined in any one of claims 10

- 16, characteri sed in that the system comprises means (11) for transmitting the dialling infor- mation to the local exchange (LE) while a voice connection exists between the terminal (MS) and the access node (AN) .