JPH09200839A - Small wireless base station - Google Patents

Abstract

(57) Abstract: There is provided a small radio base station capable of relatively easily and economically providing a service area at a remote place without the need to convert a signal from a radio base station into an RF signal. A signal from a wireless base station 1 to a small wireless base station 10 is connected via a dedicated line 13, and therefore does not need to be converted into an RF signal, and the small base station of the wireless base station 1 is not required. Is transmitted to the transceiver 33 of the small radio base station 10 via the dedicated interface 13 and the interface unit 31 from the communication interface unit 29, and the transceiver 33 operates exactly the same as the transceiver 23 in the radio base station 1. It is possible to communicate with a wireless mobile station in a service area located at a remote place.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is installed in a mobile communication system having a radio base station for communicating with a plurality of radio mobile stations by extending to a remote location where radio waves from the radio base station do not reach. A small radio base station that communicates with a station.

[0002]

2. Description of the Related Art In mobile communication, as shown in FIG. 3, a radio base station 1 is generally connected to a control station 5 via a transmission line 3 of 2 Mbps or 1.5 Mbps. The radio base station normally has a capacity capable of transmitting a plurality of carriers, and covers a radius of several hundreds to several kilometers around it as a service area divided into a plurality of sectors, and a plurality of radio mobile stations 7 within this service area. To communicate with.

Further, in order to form a service area away from the radio base station, a signal transmitted from the radio base station is once converted into an optical signal and transmitted to a remote place by an optical cable, and then RF (radio frequency) is re-established. ) When forming a service area by means of returning to a signal or relaying as an RF signal as it is, it is necessary to once convert it to another frequency and transmit it to a remote place. In any case, a device for transmitting the RF signal from the wireless base station to a remote place and converting the RF signal in the meantime is required.

[0004]

In the case where a service area is to be provided in a relatively narrow closed space such as an underground shopping area where radio waves cannot reach from a radio base station, conventionally, a signal transmitted from the base station is transmitted. Once converted to optical signal,
Since it is necessary to transmit the signal to a target remote place via an optical fiber cable and to return it to the RF signal again, there is a problem that the cost is increased due to the need for the RF conversion device and the like, which is particularly low in capacity. It is remarkable in the area.

As another method, it is conceivable to newly provide a radio base station for the service area under the control of the control station. However, if the number of base stations is increased, the control and control of the control station is increased. There is a problem that the number of base stations increases, the load on the control station increases, and the transmission path costs from the control station because the control station has to connect the transmission path although the capacity is small.

[0006] The present invention has been made in view of the above,
The purpose is to make the signal from the radio base station RF
It is an object of the present invention to provide a small radio base station which can relatively easily and economically provide a service area at a remote place without the need to convert it into a signal.

[0007]

To achieve the above object, the present invention according to claim 1 is a radio base station for communicating with a plurality of radio mobile stations by transmitting a plurality of carriers by a plurality of transceivers. In a mobile communication system having the above, the wireless base station is connected to an interface for a small wireless base station provided in place of one or a plurality of the transceivers via a dedicated line, and a signal is relayed through the dedicated line. And an interface unit that performs conversion, and a transceiver that is connected to the interface unit and that functions in the same manner as a transceiver in the wireless base station that extends from the wireless base station via the dedicated line to communicate with the wireless mobile station. The main point is to have a machine.

According to the present invention as set forth in claim 1, the small radio base station is equivalent to one in which the transceiver of the radio base station is extended to a remote place or the like via a dedicated line, and The signal from the base station does not need to be converted into an RF signal and can be transmitted to a remote place, and the upper control station can process the small radio base station as a single radio base station without special control. it can.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of a mobile communication system having a small radio base station according to an embodiment of the present invention. In the figure, the small radio base station 10 is connected to the private line 13
The wireless base station 1 is connected via a transmission line 3 to a control station 5 which performs call connection processing and voice processing. The dedicated line 13 connecting the wireless base station 1 and the small wireless base station 10 is, for example, 64 kb
It is a ps I interface dedicated line, and the dedicated line 13 is not limited to a metallic cable line, and may be configured by an optical cable line, a fixed micro line, or the like.

The radio base station 1 covers the service area 1a under the control of the control station 5, communicates with radio mobile stations existing in the service area 1a, and communicates with the radio base station 1 via the leased line 13. The connected small radio base station 10 covers a closed space such as an underground mall or a subway platform as its service area 10a and communicates with a radio mobile station existing in the service area 10a. The signal from the station 1 to the small radio base station 10 is R
The wireless base station is transmitted without being converted into the F signal, and the control of the small wireless base station does not mean that a new wireless base station is added to the control station 5, but that the wireless base station 1 is partly extended and is loaded. Can be controlled without increasing

Small radio base station 10 and radio base station 1
Is configured in detail as shown in FIG. In the figure, a radio base station 1 is connected to a control station 5 via a transmission line 3, and is connected to an interface unit 21 for performing signal conversion and signal relay with the transmission line, and the interface unit 21, and a baseband Signal processing and demodulation of received RF signals,
A plurality of transmitters / receivers 23, each of which performs processing such as modulation of a transmission signal and performs processing for one carrier, and the plurality of transmitters / receivers 2
3, an RF synthesizing / distributing unit 25 for synthesizing and distributing RF signals of a plurality of carriers, a monitor control unit 27 for monitoring and controlling each transceiver 23 and the interface unit 21, and instead of the position of the transceiver 23. The small base station interface unit 29 is provided and is connected to the small radio base station 10 via the dedicated line 13. In addition,
The RF signal forms a peripheral area of the wireless base station 1 and is transmitted between the wireless mobile station and the wireless base station 1.

Further, the small radio base station 10 has a dedicated line 13
The interface unit 31 connected to the small base station interface unit 29 of the wireless base station 1 via the interface for performing signal conversion and signal relay with the leased line 13, and transmission / reception having the same function as the transceiver 23 of the wireless base station 1. Machine 33.

The small radio base station 10 configured as described above.
In the mobile communication including, since the signal from the wireless base station 1 to the small wireless base station 10 is connected via the dedicated line 13, it is not necessary to convert it into an RF signal, and the wireless base station 1 Small base station interface unit 29
Is transmitted to the transceiver 33 of the small radio base station 10 via the leased line 13 and the interface unit 31. The transceiver 33 operates exactly like the transceiver 23 in the radio base station 1, and is located at a remote location, for example. It is possible to communicate with the wireless mobile station 7 within the service area 10a. Further, in this control, the control station 5 does not need to control the small radio base station 10 as one radio base station, and only the small radio base station 10 needs to be controlled as usual. The load on the station 5 does not increase. The number of small radio base stations 10 installed in the radio base station 1 and the number of transceivers 33 in the small radio base station 10 are 1
It is not limited to one.

[0015]

As described above, according to the present invention,
A small radio base station is equivalent to one in which a transceiver of the radio base station is extended to a remote place through a dedicated line.
Since the signal from the radio base station does not need to be converted into an RF signal and can be transmitted to a remote place, a service area at a remote place can be formed relatively easily and economically, Since the control station can process the small radio base station as one radio base station without special control, it is possible to achieve economy without increasing the load on the control station.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a mobile communication system having a small radio base station according to an embodiment of the present invention.

FIG. 2 is a diagram showing a detailed configuration of a small radio base station and a radio base station used in the mobile communication system shown in FIG.

FIG. 3 is a diagram showing a configuration of a conventional mobile communication system.

[Explanation of symbols]

 1 Radio Base Station 3 Transmission Line 5 Control Station 10 Small Radio Base Station 13 Dedicated Line 23, 33 Transceiver 29 Small Base Station Interface Unit 31 Interface Unit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsutoshi Hirokane 2-10-1 Toranomon, Minato-ku, Tokyo NTT Mobile Communication Network Co., Ltd.

Claims (1)

[Claims] 1. A mobile communication system having a radio base station that transmits a plurality of carriers by a plurality of transceivers to communicate with a plurality of radio mobile stations, wherein one or a plurality of the transceivers are provided in the radio base station. Connected to an interface for a small radio base station provided in place of the wireless LAN via a dedicated line, and relays and converts a signal via the dedicated line; and an interface unit connected to the interface unit to communicate with a wireless mobile station. A small radio base station having a transceiver functioning in the same manner as a transceiver in the radio base station extending from the radio base station via the dedicated line to perform the above.