GB2287157A

GB2287157A - Remote maintenance of a cellular base station

Info

Publication number: GB2287157A
Application number: GB9401948A
Authority: GB
Inventors: Dominic Hanlan; Jukka Kauppinen; Jukka Peltola
Original assignee: Nokia Telecommunications Oy
Current assignee: Nokia Oyj
Priority date: 1994-02-02
Filing date: 1994-02-02
Publication date: 1995-09-06
Anticipated expiration: 2014-02-02
Also published as: WO1995021510A1; GB2287157B; GB9401948D0; AU1541695A

Abstract

A GSM radio telecommunications system has a base transceiver station (BTS) 2 - 12 and a base station controller (BSC) 14 which communicate with each other over an Abis interface by microwave link or fibre optic cable. The BTS has an operations and maintenance unit 2 which may receive instructions from a terminal 8 at the BTS or a terminal 16 at the BSC thereby allowing an engineer to rectify certain faults in the BTS from the BSC. <IMAGE>

Description

Title: TelecomcationsSstems Field of the invention This invention relates to a base transceiver station (BTS) and a base station controller (BSC) for a radio telecommunications system, and is particularly applicable to GSM radio telecommunications systems.

background to the invention A GSM radio telecommunications system includes a number of base transceiver stations which provide a radio link with mobile stations (for example mobile telephones) within the range of the base transceiver stations. A base station controller communicates with the base transceiver stations through what is known as an Abis interface and has a number of functions, including the control of the operation of the base transceiver stations.

Each base transceiver station includes its own operations and maintenance unit, by means of which certain faults in the components of the base transceiver station can be rectified. Some faults can be rectified by the operations and maintenance unit in response to instructions automatically produced by another part of the system, for example the base station controller. However, there are some faults which require the intervention of an engineer who gives instructions to the operations and maintenance unit using a terminal located at the base transceiver station.

This will not normally cause problems during the initial installation and commissioning of the system, since the engineer will be at the site of the BTS when such a problem arises. However, where the problem subsequently arises, it is necessary for the engineer to travel to the BTS site specifically to rectify the problem. This can be both inconvenient and time consuming, and can also have a direct effect on the call traffic capacity of the system.

Summary of the invention According to the invention, there is provided a base transceiver station and an associated base station controller for a radio telecommunications system, the base transceiver station having an operations and maintenance unit which is connected to a man/machine interface having a terminal through which instructions can be given to the operations and maintenance unit, wherein the man/machine interface is so arranged as to allow the terminal to be situated at the base station controller.

Typically, in addition to a terminal, the man/machine interface includes processing circuitry, and associated software, for enabling an engineer to communicate with the operations and maintenance unit through the terminal.

The telecommunication system may be a GSM system, in which case said terminal is preferably connected to the operations and maintenance unit through the Abis interface.

In such a case, the terminal and the operations and maintenance unit are preferably connected via a dedicated channel on the Abis interface. The base transceiver station typically includes a transmission unit for providing a data uplink and a data downlink between the base station controller and various components of the base transceiver station and, in such a case, the operations and maintenance unit is preferably connected to the transmission unit separately from the connection between said components and the transmission unit.

Alternatively, the operations and maintenance unit and said other components may be connected to a common port of the transmission unit.

The terminal may with advantage comprise a keyboard and a visual display unit.

The base transceiver station is preferably one of a plurality of such stations, each having a respective operations and maintenance unit which can receive instructions from the terminal at the base station controller.

Preferably, the operations and maintenance units of the base transceiver stations can communicate with the terminal at the base station controller over a common dedicated channel on the Abis interface. Where that channel provides a 64 kilo-bit data link, up to 32 such operations and maintenance units can communicate -with the terminal without reducing the call traffic capacity of the system.

Since the operations and maintenance units can be instructed using a terminal at the base station controller, the invention enables an engineer to rectify certain problems in any one of the base transceiver stations, without having to travel to the base transceiver station at which the fault has occurred.

Detailed Description The invention will now be described by way of example only, with reference to the accompanying drawings in which: Figure 1 is a block diagram showing a base transceiver station and a base station controller which embody the present invention; Figure 2 is a corresponding diagram of an alternative embodiment of the invention; Figure 3 is a diagrammatic representation of the processing of certain signals at the base transceiver station shown in Figure 1; and Figure 4 is a corresponding diagram for the base transceiver station shown in Figure 2.

iledDescrition With reference to Figure 1, the components of a base transceiver station (BTS) are shown on the left of the broken line A-A, and include an operations and maintenance unit 2 connected to a port 3 of a transmission unit 4 through processing circuitry 6 which is also connected to a terminal 8 having a keyboard and a visual display unit (not shown). The connection of the unit 2 to the unit 4 is over an RS232 interface.

The operations and maintenance unit 2 is also connected to other components in the BTS, represented by the block 10, which are also connected to the unit 4 at a port 12. The BTS, along with a number of other base transceiver stations (not shown), is connected to a base station controller (BSC) 14 via an Abis interface which provides a 2 mega bit multiplexed data link between the base transceiver stations and the BSC 14. The connection between the BTS and BSC can be made through fibre optic cables, or using a microwave link.

A terminal 16, similar to the terminal 8 is connected to the BSC 14.

The man/machine interface (MMI) for the operations and maintenance unit 2 comprises the terminals 8 and 16. The circuitry 6 is operable to enable the engineer to communicate with the operations and maintenance unit 2 by means of either terminal.

With reference to Figure 3, the circuitry 6 is functionally represented by the box 18. Instructions input into the keyboard of the terminal 8 are received along the local MMI connection, represented by the arrow 20. The instructions are converted by the implementation of the man/machine interface software (by the circitry 6) into a format in which it can be understood by the operations and maintenance unit 2, prior to being relayed thereto. Similarly, signals received from the unit 2 by the circuitry 6 are converted into ignals whicb can be displayed on the visual display unit of the terminal 8.

Signals from the unit 2 are also relayed to the transmission unit 4 along the data link represented by the arrow 21) via the circuitry 6 which places them in a format in which the transmission unit 4 can insert the signals into time slots in a 64 kilo bit dedicated channel, represented by the arrow 22, in the two mega bit multiplexed data link provided by the Abis interface (and represented by the arrow 24). This information is then received by the BSC 14 and then converted into a signal which can be displayed on the visual display unit of the terminal 16.

The keyboard for the terminal 16 can be used to provide instructions for the unit 2. Those instructions are fed from the keyboard to the BSC 14, which inserts the instructions into time slots in the dedicated channel 22 for transmission to the unit 4 which extracts those instructions from the channel, relays them along the link 21 to the circuitry 6. The circuitry 6 then converts those signals into a suitable format for the unit 2, prior to being relayed to the latter.

Operations and maintenance instructions generated automatically at other parts of the system can be supplied to the unit 2 along a data link represented by the arrow 26, and signals from the unit 2 can be returned to said other parts of the system along the data link 26, which is also part of the Abis interface.

The arrangement shown in Figure 2 has some components which correspond to those of the BTS and BSC shown in Figure 1, and those components are indicated by the reference numbers of Figure 1 raised by 50.

Thus the BTS, the components of which are situated to the left of the broken line B-B, includes an operations and maintenance unit 52, and various other components 60 connected to a transmission unit 54 which, in turn, communicates with a BSC 64 over the Abis interface.

Both the BTS and the BSC have a terminal referenced 58 and 56 respectively which includes a visual display unit and a keyboard (not shown).

Instead of being connected to separate ports on the unit 54, the unit 52 and other components 60 are connected through circuitry 56 to a common port 80 on the unit 54.

The circuitry 56 is operable to multiplex signals from the units 2 and 60 into a single data stream forming the data uplink to the unit 54, and also to demultiplex the data stream on the data down link from the unit 54 into the data stream for the other components 60 and signals for the unit 52. The circuitry 56 also performs similar MMI functions as the circuitry 6.

With reference to Figure 4, the functions of the circuitry 56 are represented by the boxes 68 and 70. Box 68 represents the same functions as box 18, whilst box 70 represents various base control functions used to perform the multiplexing and demultiplexing functions, and also to convert signals received from the unit 52 into a format in which they can be inserted into the same data stream as the signals from the components 60, and to convert instructions forX the unit 52, received from the unit 54, into a format in which they can be processed by the MMI functions represented by the box 68.

The link between the unit 54 and the BSC over the Abis interface is represented by the arrow 62, and comprises a 64 kilo-bit link over which the component 60 communicates with the BSC. Signals to be exchanged between the terminal 56 and the OMU 52 are inserted in suitable time slots in that link. The arrow 64 represents the connection between the circuitry 56 and the terminal 58.

In the embodiments shown in Figures 2 and 4, instead of using the hard wire technique employed in the embodiment shown in Figures 1 and 3, data is inserted directly into the time slot data stream (between said other components 60 and the unit 54). This requires different operations and maintenance messages (from those used in the other embodiment) to be defined and included into the interface specification. Although the embodiment of Figures 2 and 4 reduces hardware requirements in the BTS, it does not have the advantage of the first embodiment, of minimum diversity of OMU Software in the BTS. By contrast, in the embodiment shown in Figures 1 and 3, the OMU in the BTS would not be aware that it was talking to the BSC via the Abis interface or directly to the MMI terminal.

For both the above embodiments, the BSC can be connected to a plurality of base transceiver stations. Such a central connection can allow for the automation of certain functions, for example the updating of system wide data which could be broadcast to all base transceiver stations connected to a given BSC. The system could also include a general learning facility allowing the operator to define a procedure to be used to instruct all the base transceiver stations, and then to transmit instructions embodying that procedure, either simultaneously or in sequence, to the base transceiver stations.

Libraries of such procedures could be built up and stored on a PC local to the controlling BSC. Such a facility will allow for more rapid and more accurate undating of the base transceiver stations either for new operating conditions or new system parameters.

Although two terminals are shown on each of the two embodiments described, it will be appreciated that each embodiment may have only one terminal connectable to a selected one of the BSC and the BTS.

Claims

1. A base transceiver station and an associated base station controller for a radio telecommunications system, the base transceiver station having an operations and maintenance unit which is connected to a man/machine interface having a terminal through which instructions can be given to the operations and maintenance unit, wherein the man/machine interface is so arranged as to allow the terminal to be situated at the base station controller.

2. A base transceiver station and a base station controller according to claim 1, in which the radio telecommunications system is a GSM system in which the base station controller and the base transceiver station communicate with each other through an Abis interface, wherein said terminal also communicates with said operations and maintenance unit through the Abis interface.

3. A base transceiver station and base station controller according to claim 2, in which the terminal and the operations and maintenance unit communicate via a dedicated channel on the Abis interface.

4. A base transceiver station and base station controller according to any of the preceding claims, in which the base transceiver station includes a transmission unit for providing a data uplink and a data downlink between the base station controller and components of the base transceiver station, wherein the operations and maintenance unit is connected to the transmission unit separately from the connection between said components and the transmission unit.

5. A base transceiver station and base station controller according to any of claims 1 to 3, in which the base transceiver station includes a transmission unit for providing a data uplink and a data downlink between the base station controller and components of the base transceiver station, wherein the operations and maintenance unit and said components are connected to a common port of the transmission unit.

6. A base transceiver station and a base station controller according to any of the preceding claims in which the terminal comprises a keyboard and a visual display unit.

7. A base transceiver station and a base station controller according to any of the preceding claims, in which the base transceiver station is one of a plurality of such stations, each having a respective operations and maintenance unit which can receive instructions from the terminal at the base station controller.

8. A base transceiver station and a base station controller according to claim 7, in which the operations and maintenance units in the base transceiver stations communicate with the base station controller via a common dedicated channel on the Abis interface.

9. A base transceiver station and base station controller substantially as described herein with reference to, and as illustrated in, Figures 1 and 3 of the accompanying drawings.

10. A base transceiver station and base station controller substantially as described herein with reference to, and as illustrated in, Figures 2 and 4 of the accompanying drawings.