JP2007221555A - Mobile communication extension system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile communication extension system for providing a mobile communication service in which the restriction of communication speed or the like is small, inside a small-scaled building, such as multiple dwelling house or shopping mall. <P>SOLUTION: The mobile communication extension system is equipped with a subscriber device, disposed for each subscriber of a community reception system and an extension base station connected to cable wiring. The extension base station is equipped with a radio transceiver that is cut out from any one of base station devices constituting a mobile communication network, a transmission interface for mediating signal transmission via a communication line connecting the radio transceiver and a baseband signal processor provided in each of the base station devices, and a first frequency conversion means for converting a radio frequency band, related to the mobile communication system to an intra-system frequency band and vice versa between the radio transceiver and the cable wiring. Each of the subscriber devices is equipped with an antenna for exchanging radio signals with a mobile communication terminal of the subscriber, and a second frequency conversion means for converting the intra-system frequency band to the radio frequency band and vice versa between the cable wiring and the antenna. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a mobile communication expansion system for capturing an area in which radio communication with a base station installed outdoors, such as an underground shopping center or the inside of a building, is difficult, within a mobile communication range.

With the advancement of mobile terminal functionality, the improvement of information communication performance of mobile terminals is progressing. With this, mobile communication systems have higher frequency bands in order to improve the amount of information transmission per unit time. It is getting used.
Since such high-frequency radio waves have a high attenuation rate and low transparency, there are cases where, for example, even in a room of an apartment house, if the radio wave moves away from the window and moves back, it may fall out of the communicable area.

A private mobile communication system has been realized as a technique for solving a region where it is difficult to use an indoor mobile communication system for a large-scale building such as an underground shopping center or a company building.
In a private mobile communication system, a private base station device dedicated to the private ground is installed together with a large number of indoor antennas installed in an underground shopping area, and the indoor mobile terminal and the private base station device are connected via the indoor antenna described above. The wireless communication is relayed to the base station of the mobile communication system by the communication device via a dedicated line, so that it can be used for a mobile communication network by indoor mobile terminals (see Non-Patent Document 1).

On the other hand, a simplified on-site mobile communication system for restaurants and the like has also been proposed.
In a simple indoor mobile communication system, a transceiver transmits and receives signals to and from an indoor mobile terminal via an indoor antenna, and this transceiver communicates with a base station via an outdoor antenna on behalf of the indoor mobile terminal. As a result, the use of a mobile communication network within a small-scale facility has been realized (see Non-Patent Document 2).

  On the other hand, with the expansion of demand for broadband communications and the diversification of television viewer preferences and viewing styles, cable TV networks using optical fiber cables and the like are being laid. There may be a cable network for cable broadcasting services. In particular, large-capacity cable networks that can be shared by residents are becoming common facilities in apartment houses such as condominiums that have been sold in recent years.

By transmitting a mobile terminal signal superimposed on a cable TV network laid in an apartment house such as a condominium, a wireless transmission / reception device similar to the above-described simplified local mobile communication system is used. A technique shared by households has also been proposed (see Patent Documents 1 and 2).
In the indoor mobile communication system using the joint reception system disclosed in Patent Document 1, as shown in FIG. 7, an indoor antenna 41, an antenna branching synthesizer (DIV) 42, a relay trunk 43, and a frequency converter are installed at each subscriber house. The indoor equipment 40 including (F-CONV) 44 is installed, and the signal of the mobile terminal is superimposed on the signal of the joint reception system by the indoor equipment 40 and transmitted to the antenna device 45 through the coaxial cable. Then, the frequency converter 44, the relay trunk 43, and the antenna branching / combining unit 42 provided in the antenna device 45 perform the reverse operation to the indoor equipment 40 described above, and the base station of the mobile communication system via the antenna 46. By connecting wirelessly to 47, the connection of the indoor mobile terminal to the mobile communication network is realized. In FIG. 7, a distributor (H) is provided at each branch of the coaxial cable connected to the common receiving antenna, and the television receiver and the above-described indoor equipment 40 are coaxially connected via this distributor. Connected to cable.

In addition, a technique for reducing the cost of installing a wireless base station in a depopulated area using an existing cable television network has been proposed (see Patent Document 3).
JP 2002-84225 A Japanese Patent Laid-Open No. 2001-292088 JP-A-6-98046 “IMCS: System using IMCS”, “Use Cases for Corporate Services Tab” [online], N.C. Tee. Tee. Docomo Hokkaido, [03/10/20], Internet <URL: http://www.nttdocomo-h.co.jp/houjin/houjin.css> "Simple IMCS", Simple IMCS device configuration section on the product / service tab, [online], DOCOMO Engineering Co., Ltd. [03/10/20], Internet <URL: http // www.nttdocomo.co.jp / goods / imcs / gaiyou.html>

  In the indoor mobile communication system using the simplified indoor mobile communication system described above and the joint reception system disclosed in Patent Document 1, the wireless transmission / reception apparatus provided in these systems is installed outdoors by a communication provider providing mobile communication services. It is treated as one terminal equivalent to a general mobile terminal in the area managed by the base station. And, since the indoor mobile terminals whose signals are relayed by the wireless transmission / reception devices of these systems are located under this wireless transmission / reception device, when viewed from the base station of the mobile communication system, the outdoor mobile terminals Will be treated as a low-level terminal.

Because of this hierarchical relationship, indoor mobile terminals that use an indoor mobile communication system that uses a simplified private mobile communication system or the joint reception system disclosed in Patent Document 1 use the mobile communication system directly outdoors. Compared to a general mobile terminal, it is subject to greater restrictions in terms of connection and the like.
In addition, an antenna for wireless communication with the base station by the wireless transmission / reception apparatus provided in these systems needs to be placed in an area managed by the base station, and in order to guarantee connection stability and the like. In order to apply the system, there are also restrictions on the location conditions of stores and apartment houses, so that the arrangement close to the base station is preferable even in the area.

Furthermore, since the connection with the mobile communication system is a wireless connection, it is inevitable that the line quality fluctuates with time, so that services that can be used by indoor mobile terminals are greatly limited. In particular, it is almost impossible to provide services that require high traffic and services that require high-speed communication.
In addition, the wireless transmission / reception apparatus provided in the indoor mobile communication system using the simplified private mobile communication system and the joint reception system of Patent Document 1 is a process other than the process of relaying a radio signal such as a process for managing an indoor mobile terminal. Since the processing is also borne, the scale of the apparatus increases and the cost also increases.

On the other hand, when viewed from the base station side of the mobile communication system, since this wireless transmission / reception device is treated as a mobile terminal, the indoor mobile terminals relay-connected via this wireless transmission / reception device are individually monitored and controlled. I could not.
On the other hand, in a large-scale private mobile communication system, since the connection between the private base station apparatus and the base station apparatus of the mobile communication system is a connection using a dedicated line, there is no restriction on location conditions. However, since the local base station apparatus is an apparatus having a function comparable to that of the base station apparatus in the mobile communication network, its introduction cost is very high and is not suitable for a small-scale system for an apartment house or the like.

  An object of the present invention is to provide a mobile communication expansion system capable of providing a mobile communication service with less restrictions such as communication speed in a small building such as an apartment house or a shopping street.

A first mobile communication expansion system according to the present invention includes an extended base station including a wireless transmission / reception apparatus, a transmission interface, and first frequency conversion means, a subscriber apparatus including an antenna and second frequency conversion means. It consists of.
The principle of the first mobile communication expansion system according to the present invention is as follows.
Consists of a base station apparatus configured to process baseband signals related to a plurality of wireless transmission / reception apparatuses having functions of independently processing wireless communication for areas corresponding to each area and managing mobile terminals in the area by the baseband signal processing apparatus In a mobile communication expansion system for extending the communication range of a mobile communication network to a facility or building having a cable wiring for a joint reception system including a cable broadcasting service and a cable television service, a subscriber unit It is arranged for each subscriber of the joint reception system. The overhanging base station is connected to the cable wiring. In this overhanging base station, the wireless transmission / reception device is cut out from any of the base station devices constituting the mobile communication network. The transmission interface mediates signal transmission via a communication line that connects between the wireless transmission / reception device and the baseband signal processing device provided in the base station device. The first frequency conversion means is a frequency between a radio transmission / reception device and a cable wiring between a radio frequency band related to the mobile communication system and an in-system frequency band determined in consideration of an empty frequency band in the joint reception system. Convert between each other. In each subscriber unit, the antenna transmits and receives radio signals to and from the subscriber's mobile terminal. The second frequency conversion means mutually performs frequency conversion between the in-system frequency band and the radio frequency band between the cable wiring and the antenna.

The operation of the first mobile communication extension system configured as described above is as follows.
The signal of the radio frequency band processed by the radio transmitting / receiving apparatus of the overhanging base station is converted into the signal of the in-system frequency band by the first frequency conversion means, and is superimposed and transmitted with the signal of the joint reception system by the cable wiring, A subscriber device is reached. In this subscriber unit, the above-mentioned signal in the in-system frequency band is converted into a radio frequency band signal by the second frequency conversion means, and then transmitted through the antenna to reach the subscriber's mobile terminal.

  A radio signal transmitted from a subscriber's mobile terminal is received by an antenna provided in the subscriber unit, and then converted into an upstream signal in the in-system frequency band by the second frequency conversion means and transmitted to the cable wiring. Then, it is superimposed on the signal of the common reception system and transmitted through this cable wiring to reach the overhanging base station. In this way, the uplink signal in the in-system frequency band transmitted from the subscriber unit to the extended base station is converted into a radio frequency band signal by the first frequency conversion means and used for processing of the radio transmission / reception apparatus. . The baseband signal obtained by the processing of the wireless transmission / reception device reaches the baseband signal processing device of the base station device via the transmission interface and the communication line, and the baseband signal processing device uses the baseband signal processing device to Is processed as a signal equivalent to a baseband signal from the wireless transceiver.

  In other words, each subscriber connected to the overhanging base station via the cable wiring of the common reception system is treated as a subscriber in an area managed by the radio transmission / reception apparatus provided in the overhanging base station. Like a subscriber in an outdoor area managed by another wireless transmission / reception device that constitutes a base station device together with the device, a service that requires high-speed communication can be enjoyed without major restrictions.

The second mobile communication expansion system according to the present invention is configured by connecting a plurality of first mobile communication expansion systems via distribution means.
The principle of the second mobile communication expansion system according to the present invention is as follows.
The distribution means converts a communication line connected to a transmission interface provided in each of a plurality of mobile communication expansion systems into a single communication line, and connects to a baseband signal processing device provided in the base station.

The operation of the second mobile communication extension system configured as described above is as follows.
Since the extended base stations installed in a plurality of joint reception systems are connected to the baseband signal processing device as a single wireless transmission / reception device via the distribution means, each area corresponding to these joint reception systems is physically Although it is scattered at distant points, it is treated as one area managed by a single wireless transmission / reception device.

An allocation unit that allocates a transmission capacity of the communication line connected to the baseband signal processing device to each of the plurality of extended base stations, and an allocation unit provided in the second mobile communication expansion system described above; The third mobile communication expansion system can also be configured by including a changing means for changing the transmission capacity assigned to each overhanging base station by the means.
In the third mobile communication extension system configured as described above, the changing means uses each overhang by the allocating means in accordance with the demand (or observed traffic) expected in the joint reception system in which each overhang base station is arranged. By changing the allocation of the transmission capacity to the base station, it is possible to effectively utilize both the transmission capacity of the communication line and the processing capability of the baseband signal processing apparatus.

A fourth mobile communication expansion system according to the present invention comprises an upstream local oscillator and a downstream local oscillator in the first frequency conversion means and the second frequency conversion means of the first mobile communication expansion system described above. Is done.
The principle of the fourth mobile communication expansion system according to the present invention is as follows.
In the first frequency conversion means and the second frequency conversion means provided in the first mobile communication extension system described above, the uplink local oscillator is an uplink that is a reference for frequency conversion related to an uplink signal directed to the base station of the mobile communication system. An upstream conversion signal of a reference frequency is generated. The downlink local oscillator generates a downlink conversion signal having a downlink reference frequency that is a reference for frequency conversion regarding the downlink signal directed to the subscriber of the joint reception system.

The operation of the fourth mobile communication expansion system configured as described above is as follows.
The uplink signal and the downlink signal are frequency-converted based on the uplink reference frequency and the downlink reference frequency corresponding to the uplink local oscillator and the downlink local oscillator provided independently of each other, so the uplink signal and the downlink signal in the radio frequency band Regardless of the arrangement, it is possible to freely determine the arrangement of the upstream signal and the downstream signal sent to the cable wiring of the common reception system in the system frequency band.

Also, a provider that provides a mobile communication system by appropriately determining the oscillation frequencies of the above-described uplink local oscillator and downlink local oscillator according to the radio frequency band used by the mobile communication system to be expanded. Regardless of this, the frequency bands of signals superimposed on the joint reception system in the cable wiring of the joint reception system can be collected.
The fifth mobile communication expansion system according to the present invention is the same as the first mobile communication expansion system described above, and includes a control signal generation unit, a control signal distribution unit, and an adjustment unit.

The principle of the fifth mobile communication expansion system according to the present invention is as follows.
In the first mobile communication expansion system described above, the control signal generation means is a reference frequency related to frequency conversion between the in-system frequency band and the radio frequency band in the second frequency conversion means provided in each subscriber unit. Is generated as a signal in a control frequency band different from the in-system frequency band. The control signal distribution means superimposes the control signal on the signal of the joint reception system and distributes it via the cable wiring. The adjusting means is provided in each subscriber unit, and adjusts the reference frequency of the corresponding second frequency converting means based on the frequency designation information indicated by the control signal in response to reception of the control signal in the control frequency band. To do.

The operation of the fifth mobile communication expansion system configured as described above is as follows.
The control signal generated by the control signal generation unit is superimposed on the signal of the joint reception system by the control signal distribution unit, distributed to each subscriber device via the cable wiring, and adjusted by the adjustment unit for reference frequency adjustment processing. By providing, it is possible to remotely control the reference frequency in the second frequency conversion means provided in each subscriber unit according to the frequency designation information included in this control signal.

That is, the reference frequency of the second frequency conversion means provided in each subscriber device can be set collectively after the installation of each subscriber device, or can be changed as necessary.
Further, the fifth mobile communication expansion system described above is provided in each subscriber unit for monitoring a reference frequency relating to a corresponding second frequency conversion means, and a monitoring control signal indicating a monitoring result. Report means for generating a signal in the frequency band, superimposing it on the signal of the joint reception system and sending it to the cable wiring, and collecting a monitoring control signal sent to the cable wiring, It is also possible to configure a sixth mobile communication expansion system by including monitoring means for collectively monitoring reference frequencies related to the frequency conversion means.

In such a sixth mobile communication extension system, the reference frequency of the frequency conversion function in each subscriber apparatus of the joint reception system can be monitored in a lump from the extended base station or the base station apparatus of the cut-out source.
A seventh mobile communication expansion system according to the present invention includes a reference oscillator and clock distribution means.

The principle of the seventh mobile communication expansion system according to the present invention is as follows.
In the first mobile communication extension system described above, the reference oscillator generates a reference oscillation signal having a predetermined frequency that can be transmitted by being superimposed on an empty frequency band of the joint reception system. The clock distribution unit supplies the reference oscillation signal as a common reference signal to the first frequency conversion unit and the second frequency conversion unit via the cable wiring.

The operation of the seventh mobile communication extension system configured as described above is as follows.
The reference oscillation signal formed by the reference oscillator is supplied to the first frequency conversion means and the second frequency conversion means by the clock distribution means via the cable wiring, and is supplied to the frequency conversion processing by each. Accordingly, the coincidence between the reference frequency related to the frequency conversion performed by the first frequency converting means and the reference frequency related to the frequency conversion performed by the second frequency converting means is related to the frequency accuracy of the reference oscillator generated by the reference oscillator. Guaranteed regardless.

Furthermore, the clock generation circuit provided for the internal processing of the wireless transmission / reception apparatus provided in the extended base station is used as a reference oscillator, and the clock signal generated by the clock generation circuit is supplied by the clock distribution means. It is also possible to distribute to the first frequency conversion means and the second frequency conversion means.
In such a configuration, the high-accuracy clock signal generated by the clock generation circuit originally provided in the wireless transmission / reception apparatus is converted into the first frequency conversion means and the second frequency conversion via the cable wiring of the joint reception system. Supplied to both means.

  In the mobile communication expansion system according to the present invention, one of the radio transmission / reception devices constituting the base station device is cut out to form the above-described overhanging base station, whereby the joint receiving system in which this overhanging base station is installed Can be treated as a mobile terminal staying in one of the areas managed by the base station apparatus that is the cut-out source. This provides, for example, services equivalent to users who can communicate wirelessly with base stations outdoors to mobile terminals of subscribers in apartments such as condominiums and shopping malls and in facilities. can do.

Moreover, regardless of the physical distance between the base station device and the building where the joint reception system is installed, by connecting the base station device and the extended base station using a communication line such as an optical fiber cable, The service area of the mobile communication system can be expanded inside this building.
In addition, a plurality of overhanging base stations are connected to a base station apparatus of a mobile communication system via a distribution means, and signal processing related to a subscriber of a joint reception system in which these overhanging base stations are installed As a result, the performance of the baseband signal processing function provided in the base station apparatus can be fully utilized.

Furthermore, by assigning an appropriate transmission capacity to the transmission path between the baseband signal processing function of the base station apparatus and each extended base station, baseband signal processing is performed according to the number of subscribers of each joint reception system. Capability of functions can be allocated appropriately.
On the other hand, in the extended base station and each subscriber unit, the frequency of the in-system for superimposing transmission with the signal of the joint reception system is applied by performing frequency conversion by applying different reference frequencies to the uplink signal and the downlink signal. The degree of freedom regarding arrangement can be greatly expanded.

In addition, by providing a mechanism for remotely monitoring and controlling the reference frequency related to the second frequency conversion function provided in each subscriber device, for example, each subscriber device can be changed in response to a change in the radio frequency band. Since it can be performed in a lump in the overhanging base station or the base station device that is the cut-out source, system maintenance management can be facilitated.
In addition, by providing a mechanism for guaranteeing the coincidence of the reference frequency related to frequency conversion between the overhanging base station and each subscriber device, the performance condition related to the circuit for generating the signal of the reference frequency can be relaxed. In addition, the cost of the overhanging base station and each subscriber unit can be reduced.

  In particular, when applying a mechanism to supply a clock signal generated by a reference oscillator provided in advance to the radio transmitting / receiving device of the overhanging base station to the frequency conversion function of the overhanging base station and each subscriber unit, the mobile communication expansion Since it is not necessary to prepare a new reference oscillator for the system, the cost can be further reduced.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 1 shows a first embodiment of a mobile communication expansion system according to the present invention.
A master base station apparatus 210 shown in FIG. 1 is one of base station apparatuses that constitute a mobile communication network. A baseband signal is transmitted between radio transmission / reception apparatuses 211 _{1 to} 211 _n−1 and a transmission interface 214 via a bus. It is configured to be connected to the processing device 212 and the control unit 213. Hereinafter, when these wireless transmission / reception devices 211 _{1 to} 211 _n−1 are collectively referred to, they are simply referred to as the wireless transmission / reception device 211.

  The baseband signal processing device 212 and the control unit 213 illustrated in FIG. 1 have processing capabilities necessary for controlling signals related to the n radio transmission / reception devices 211. The n-th wireless transmission / reception device 211 belonging to the master base station device 210 is arranged as the wireless transmission / reception device 221 of the extended base station 220 installed in or close to the building where the joint reception system is installed. The master base station apparatus 210 is connected to the transmission interface 214 inserted into the slot instead of the n-th wireless transmission / reception apparatus 211 via the optical fiber cable.

Here, a general base station apparatus is configured by connecting a plurality of (about 20) radio transmission / reception apparatuses to the above-described baseband signal processing apparatus 212 and control unit 213 by inserting them into slots provided in the chassis. One of these can be extracted and installed in the extended base station 220.
By connecting in this way, one of the n radio transmitting / receiving apparatuses 211 belonging to the master base station apparatus 210 is installed in an apartment house or the like that is physically separated from the master base station apparatus 210. It can be remotely located in the joint reception system. The wireless transmitter / receiver 211 that is remotely arranged as described above, that is, the wireless transmitter / receiver 221 of the extended base station 220, can be seen from the baseband signal processing device 212 provided in the master base station device 210. It is equivalent to the other wireless transmission / reception device 211 housed in. Accordingly, the service areas provided by the wireless transmission / reception devices 221 arranged in the extended base station 220 are the service areas provided by the wireless transmission / reception devices 211 _{1 to} 211 _n−1 housed in the master base station device 210, respectively. It is possible to provide an equivalent service.

  The radio transmission / reception apparatus 221 arranged in the extended base station 220 shown in FIG. 1 is connected to a distributor (indicated by a symbol “H”) provided in the cable wiring of the joint reception system via the frequency converter 223. Yes. Each subscriber house of this joint reception system includes a television (TV) receiver 201 and a subscriber device 230 including a frequency converter 231 and a wireless communication antenna 232. And the TV receiver 201 are connected to the cable wiring described above via a distributor.

  The frequency converters 223 and 231 shown in FIG. 1 perform conversion between the radio frequency band to which the radio transmission / reception device 221 and the antenna 232 are adapted and the in-system frequency band secured in the free frequency band of the joint reception system. . For example, as shown in FIGS. 2 (a) and 2 (b), an uplink channel (indicated by a symbol “U” in FIG. 2) and a downlink channel (indicated by a symbol “D” in FIG. 2) of a mobile communication system using a 2 GHz band. Is converted into a frequency band (for example, 770 MHz to 1 GHz) to which various TV radio waves (VHF, UHF, BS, and CS) are not allocated, and a mobile communication system together with signals related to these TV radio waves Can be transmitted in a superimposed manner.

FIG. 3 shows a detailed configuration of the frequency conversion unit.
In the overhanging base station 220 shown in FIG. 3, a downlink signal coming from the master base station apparatus 210 via the transmission interface 222 is input to the transmission circuit (TX) 225 via the modem 224, and a radio frequency band (for example, 2 GHz band) signal. The signal of this radio frequency band is indicated by a symbol D in the downlink signal channel (FIG. 2B) secured in the above-mentioned system frequency band by the transmission side conversion circuit (T-CONV) 228 of the frequency conversion unit 223. The signal is transmitted to the cable of the common reception system and transmitted together with the signal of the common reception system.

The downlink signal superimposed and transmitted in this way is converted into a radio frequency band signal by the reception side conversion circuit (R-CONV) 234 of the frequency conversion unit 231 provided in the subscriber unit 230, and is transmitted via the antenna 232. Wirelessly transmitted.
On the other hand, the radio signal transmitted from the mobile terminal of the subscriber of the joint reception system is converted into an uplink signal in the radio frequency band by the antenna 232 described above. This uplink signal is further transmitted from an uplink signal channel (indicated by symbol U in FIG. 2B) secured in the intra-system frequency band by the transmission side conversion circuit 233 (T-CONV) of the frequency conversion unit 231. After being converted into a signal, it is sent out to the cable wiring of the joint reception system, and is superimposed and transmitted together with the signal of the joint reception system.

  The uplink signal thus superimposed and transmitted is converted into a radio frequency band signal by the reception side conversion circuit (R-CONV) 229 of the frequency conversion unit 223 provided in the extended base station 220, and the reception circuit (RX) The data is transferred to the transmission interface 222 via the H.226 and the modem 224, and used for processing of the baseband signal processing device 212 provided in the master base station device 210.

  In the frequency converter 223 shown in FIG. 3, the reference oscillator 242 generates a reference signal having a frequency located in the vacant frequency band in the joint reception system, as indicated by reference numeral “OSC” in FIG. This reference signal is used for generating a conversion frequency by the local oscillator (LO) 241 and is also distributed to each subscriber device 230 via the cable wiring of the joint reception system and provided in the frequency conversion unit 231. The local oscillator (LO) 235 provides a conversion frequency generation process.

In this way, the local oscillator 241 provided in the frequency conversion unit 223 and the local oscillator 235 provided in the frequency conversion unit 231 in each subscriber device 230 use the free frequency band of the joint reception system for the reference signal. Thus, it is possible to guarantee the coincidence of the conversion frequencies generated by these local oscillators 241 and 235 by distributing in common.
Further, as shown in FIG. 4, the reference signal from the reference oscillator 243 provided in the control unit 227 of the wireless transmission / reception apparatus 221 is extracted and supplied to the frequency conversion unit 223 of the extended base station 220, and the joint reception system It is also possible to supply the frequency conversion unit 231 of each subscriber device 230 via the cable wiring.

In this way, in the configuration using the reference oscillator 243 originally provided in the wireless transmission / reception device 221, there is no need to newly provide a reference oscillator for the mobile communication expansion system. The cost related to each subscriber device 230 can be reduced.
Further, the local oscillators (LO) 241 and 235 shown in FIG. 4 are respectively composed of a downlink signal local oscillator (LO-D) 244 and an uplink signal local oscillator (LO-U) 245. Frequency conversion is performed independently for each signal.

As a result, as shown in FIGS. 2D and 2E, regardless of the arrangement of the uplink channel and downlink channel in the radio frequency band, the uplink signal channel and downlink signal for the in-system frequency band at appropriate intervals. It is possible to arrange channels.
It is also possible to change the oscillation frequencies of the local oscillators 241 and 235 related to the frequency conversion by these frequency conversion units 223 and 231 after installation.
(Second Embodiment)
FIG. 5 shows a second embodiment of the mobile communication expansion system according to the present invention.

In the frequency conversion unit 223 shown in FIG. 5, the monitoring control unit 246 sets frequency information such as a frequency division ratio in the local oscillator 241 in accordance with an instruction from the control unit 227 of the wireless transmission / reception device 221, and The conversion control information indicating the frequency or the frequency to be obtained is superimposed using a control channel (indicated by the symbol “SV ₁ ” in FIG. 2 (f)) provided in the vacant frequency band of the joint reception system. It is transmitted and distributed to each subscriber device 230.

The control signal distributed using this control channel is passed to the monitor control unit 247 provided in the frequency conversion unit 231 of each subscriber device 230, and the local oscillator 235 is set by the monitor control unit 247. Provided.
In this way, by distributing an appropriate control signal in accordance with an instruction from the control unit 227 of the radio transmission / reception device 221 of the overhanging base station 220 using the free frequency band of the joint reception system, In addition to the frequency converter 223, the frequency converter 231 of each subscriber device 230 can be remotely controlled to set the frequencies of the local oscillators 241 and 235 provided therein.

Thus, for example, even when the vacant area in the joint reception system is changed after the extension base station 220 or each subscriber device 230 is installed, the frequency conversion units 223 and 231 perform the above. By remotely controlling the frequency conversion operation and adjusting the in-system frequency band, it is possible to cope flexibly.
In addition, by realizing such remote control, it is possible to use the subscriber device 230 having the same configuration regardless of the mobile communication system to be expanded into a building or the like where the joint reception system is installed. It becomes. In other words, when the mobile communication system provided by different operators is expanded indoors by applying the present invention, it is possible to share the subscriber apparatus installed in each subscriber house of the joint reception system. it can.

At this time, if the frequency information of the local oscillators 241 and 235 is set so as to be superimposed and transmitted using the same in-system frequency band regardless of the mobile communication system to be expanded, the transmission conversion circuit 228, Design of the H.233 and the receiving conversion circuits 229 and 234 can be simplified.
Of course, the frequency information for the upstream signal and the frequency information for the downstream signal are respectively designated from the control unit 227 described above, and the control signal indicating them is distributed by the monitoring control unit 246, so that the frequency conversion unit 223, It is possible to remotely control the downstream signal oscillator 244 and the upstream signal oscillator 245 that constitute the local oscillators 241 and 235 respectively provided in the H.231.

On the other hand, the monitoring control unit 247 provided in the frequency conversion unit 231 of each subscriber device 230 monitors the oscillation frequency of the corresponding local oscillator 235, and the monitoring result is further provided in the vacant frequency band of the joint reception system described above. The control channel (shown with the symbol “SV ₂ ” in FIG. 2 (f)) is superimposed and transmitted, and collected by the monitoring control unit 246 provided in the frequency conversion unit 223 of the extended base station 220. It is also possible to notify the control unit 227 of the wireless transmission / reception device 221 together with information indicating the frequency of the local oscillator 241 in the frequency conversion unit 223.

In this way, remote monitoring of the frequency converter 231 provided in each subscriber device 230 can be realized.
By realizing such remote monitoring and remote control, the maintenance management work of the mobile communication extension system can be made extremely easy, and the cost required for the maintenance management work can be greatly reduced.

  By the way, it is considered that the traffic related to the subscriber of the collective housing joint reception system as described above is much smaller than the traffic related to one sector managed by each wireless transmission / reception device 211 provided in the master base station device 210. . Therefore, as described above, in the configuration in which the wireless transmission / reception device 221 provided in the extended base station 220 is connected as one of the wireless transmission / reception devices 211 of the master base station device 210, the processing capability of the baseband signal processing device 212 is achieved. A large surplus may occur.

Next, a method for effectively utilizing the enormous processing capacity of the baseband signal processing apparatus 212 provided in the master base station apparatus 210 will be described.
(Third embodiment)
FIG. 6 shows a third embodiment of the mobile communication expansion system according to the present invention.
In the mobile communication extension system shown in FIG. 6, the transmission interface 214 provided in the master base station apparatus 210 is connected to the m joint reception systems via the distributor 215, and the extended base station 220 is installed. It is connected to a transmission interface 222 provided at _{1 to} 220 _m .

For example, the distributor 215 shown in FIG. 6 allows the transmission capacity of the optical fiber transmission line between the distributor 215 and the transmission interface 214 of the master base station apparatus 210 to be the above-described m extended base stations 220 ₁ to 220 ₁ . Evenly allocated to 220 _m . Thereby, in the baseband signal processing apparatus 212 of the master base station apparatus 210, the processing capability allocated to one radio transmission / reception apparatus 211 is transferred to m areas provided by the joint reception system corresponding to these extended base stations. It can be assigned in common to the signal processing involved.

That is, the signal processing related to the subscribers in the area expanded corresponding to a plurality of joint reception systems is collectively performed as if the signal processing related to the area managed by the single wireless transmission / reception device 211 is performed. By using the processing of the band signal processing device 212, the processing capability of the baseband signal processing device 212 can be effectively utilized.
Further, by changing the ratio of the transmission capacity allocated to the transmission between the extended base stations 220 _{1 to} 220 _m by the distributor 215 shown in FIG. 6, it corresponds to the number of subscribers of each joint reception system. It is possible to flexibly cope with a difference in demand for the mobile communication system, and to appropriately allocate the processing capability of the baseband signal processing device 212.

Further, as shown in FIG. 6, the wireless transmission device 221 provided in the extended radio base station 220 connects the antenna 248 (in FIG. 6 showed a case of installing the extended radio base station 220 _1), the extended radio base An area close to the station 220 can be added to an expanded area using the joint reception system to provide a mobile communication service.
For example, by arranging the antenna as described above in a common space such as an entrance lobby of an apartment house, an indoor parking lot, and an elevator, it is possible to incorporate these common spaces into the expanded area.

Regarding the above description, the following items are further disclosed.
(Supplementary note 1) A base having a configuration in which baseband signals related to a plurality of wireless transmission / reception devices having a function of managing wireless communication in an area corresponding to each independently and managing mobile terminals in the area are processed by the baseband signal processing device In a mobile communication expansion system for extending a communicable range of a mobile communication network composed of station devices into a facility or building having a cable wiring for a joint reception system including a cable broadcasting service and a cable television service, It has a subscriber unit arranged for each subscriber of the joint reception system and an extended base station connected to the cable wiring, and the extended base station was cut out from any of the base station devices constituting the mobile communication network. Radio transceiver, radio transceiver and base station In a radio frequency band and a joint reception system related to a mobile communication system between a transmission interface that mediates signal transmission through a communication line connecting between the baseband signal processing apparatus and a wireless transmission / reception apparatus and cable wiring First frequency conversion means for mutually performing frequency conversion between the in-system frequency band determined in consideration of the vacant frequency band, and each subscriber unit transmits a radio signal to the subscriber's mobile terminal. And a second frequency conversion means for mutually performing frequency conversion between the in-system frequency band and the radio frequency band between the antenna and the cable wiring and the antenna. Mobile communication expansion system. (1)
(Supplementary note 2) A plurality of mobile communication expansion systems according to supplementary note 1 and a communication line connected to a transmission interface provided in each of the plurality of mobile communication expansion systems are converted into a single communication line to be provided in the base station. And a distribution means for connecting to the baseband signal processing apparatus. (2)
(Supplementary note 3) Allocation means for allocating the transmission capacity of the communication line connected to the baseband signal processing device to each of the plurality of extended base stations, to the distribution means provided in the mobile communication extension system according to supplementary note 2. And a changing means for changing the transmission capacity assigned by the assigning means to each extended base station.

(Supplementary note 4) In the mobile communication extended system according to supplementary note 1, the first frequency conversion means and the second frequency conversion means have an uplink reference frequency serving as a reference for frequency conversion related to an uplink signal directed to the base station of the mobile communication system. An uplink local oscillator that generates an uplink conversion signal and a downlink local oscillator that generates a downlink conversion signal of a downlink reference frequency that is a reference for frequency conversion related to a downlink signal directed to a subscriber of the joint reception system Mobile communication expansion system. (3)
(Supplementary Note 5) A provider that provides a mobile communication system by appropriately determining the oscillation frequencies of the uplink local oscillator and the downlink local oscillator according to the radio frequency band used by the mobile communication system to be expanded. The mobile communication expansion system according to appendix 4, wherein the frequency bands of the signals superimposed on the common reception system in the cable wiring of the common reception system are collected regardless of whether or not.

(Supplementary note 6) In the mobile communication extended system according to supplementary note 1, a reference frequency related to frequency conversion between the in-system frequency band and the radio frequency band in the second frequency conversion means provided in each subscriber unit is designated. Control signal generating means for generating a control signal representing frequency designation information as a signal in a control frequency band different from the in-system frequency band, and control for superimposing the control signal on the signal of the joint reception system and distributing it via cable wiring A signal distribution unit and a reference frequency of a second frequency conversion unit corresponding to the signal distribution unit and the corresponding second frequency conversion unit based on the frequency designation information indicated by the control signal in response to reception of the control signal in the control frequency band. A mobile communication expansion system comprising adjustment means for adjustment. (4)
(Supplementary note 7) In the mobile communication extended system according to supplementary note 6, a monitoring unit provided in each subscriber unit for monitoring a reference frequency related to a corresponding second frequency conversion unit, and a supervisory control signal indicating a monitoring result are controlled. A reporting means for generating a signal in the frequency band for use and superimposing it on the signal of the joint reception system and sending it to the cable wiring; and collecting a monitoring control signal sent to the cable wiring, A mobile communication expansion system, comprising: monitoring means for collectively monitoring a reference frequency related to the frequency conversion means.

(Supplementary note 8) In the mobile communication extension system according to supplementary note 1, a reference oscillator that generates a reference oscillation signal of a predetermined frequency that can be transmitted while being superimposed on a vacant frequency band of the joint reception system, and a reference oscillation via a cable wiring A mobile communication expansion system, comprising: clock distribution means for supplying a signal as a common reference signal to the first frequency conversion means and the second frequency conversion means. (5)
(Supplementary note 9) The mobile communication expansion system according to supplementary note 8, wherein the reference oscillator is a clock generation circuit provided for internal processing of the wireless transmission / reception apparatus provided in the extended base station.

As described above, according to the mobile communication expansion system according to the present invention, the mobile terminal can be moved to individual subscriber companies in the joint reception system by using the joint reception system such as cable television installed in the apartment house. The service area of the communication system can be expanded, and a service equivalent to an outdoor service area can be provided to subscribers in the expanded area.
In recent years, mobile terminals are not just a means of contact outdoors, but are information terminals with a wide variety of functions represented by the Internet connection function. These various functions can be used indoors as well as outdoors. In view of the fact that there are many, it is extremely meaningful to provide services equivalent to those in outdoor service areas in service areas extended indoors. Therefore, the mobile communication expansion system according to the present invention is very useful not only in the mobile communication service but also in various technical fields related to the mobile communication service, for example, various Internet-related services.

It is a figure which shows 1st Embodiment of the mobile communication expansion system concerning this invention. It is a figure explaining frequency conversion. It is a figure which shows the detailed structure of a frequency conversion part. It is a figure which shows another structural example of a frequency conversion part. It is a figure which shows 2nd Embodiment of the mobile communication expansion system concerning this invention. It is a figure which shows 3rd Embodiment of the mobile communication expansion system concerning this invention. It is a figure which shows the structural example of the conventional indoor mobile communication system.

Explanation of symbols

201 TV receiver 210 master base station apparatus 211 _{1 to} 211 _n−1 , 221 wireless transmission / reception apparatus 212 baseband signal processing apparatus 213 control unit 214, 222 transmission interface 215 distributor 220 overhang base station 223 frequency conversion unit 224 modem 225 transmission Circuit (TX)
226 Receiver circuit (RX)
227 Control unit 232, 248, 41, 46 Antenna 228, 233 Transmission side conversion circuit (T-CONV)
229, 234 Reception side conversion circuit (R-CONV)
230 Subscriber equipment 235, 241 Local oscillator (LO)
242 Reference oscillator 244 Downward signal local oscillator (LO-D)
245 Upward signal local oscillator (LO-U)
246, 247 Monitoring control unit 40 Indoor device 42 Antenna branching / combining unit (DIV)
43 Relay trunk 44 Frequency converter (F-CONV)
45 Antenna device 47 Base station

Claims (5)

From a base station apparatus configured to process a baseband signal related to a plurality of wireless transmission / reception apparatuses having a function of processing wireless communication related to each corresponding area independently and managing mobile terminals in the area by the baseband signal processing apparatus In a mobile communication expansion system for extending a communicable range of a configured mobile communication network to a facility or building having a cable wiring for a joint reception system including a cable broadcasting service and a cable television service,
A subscriber unit arranged for each subscriber of the joint reception system;
An overhanging base station connected to the cable wiring,
The overhang base station is
A wireless transmission / reception device cut out from any of the base station devices constituting the mobile communication network;
A transmission interface that mediates signal transmission via a communication line that connects between the radio transceiver apparatus and a baseband signal processing apparatus provided in the base station apparatus;
Frequency conversion between a radio frequency band related to the mobile communication system and an in-system frequency band determined in consideration of an empty frequency band in the joint reception system is mutually performed between the radio transmission / reception apparatus and the cable wiring. First frequency converting means for performing,
Each subscriber unit is
An antenna for transmitting and receiving radio signals to and from the mobile communication terminal of the subscriber;
A mobile communication expansion system comprising: second frequency conversion means for mutually performing frequency conversion between the in-system frequency band and the radio frequency band between the cable wiring and the antenna. . A plurality of mobile communication expansion systems according to claim 1;
Distribution for converting the communication line connected to the transmission interface provided in each of the plurality of mobile communication expansion systems into a single communication line and connecting to the baseband signal processing device provided in the base station And a mobile communication expansion system. The mobile communication expansion system according to claim 1,
The first frequency converting means and the second frequency converting means are:
An uplink local oscillator that generates an uplink conversion signal of an uplink reference frequency serving as a reference for frequency conversion related to an uplink signal directed to a base station of the mobile communication system;
A mobile communication expansion system comprising: a downlink local oscillator that generates a downlink conversion signal having a downlink reference frequency that is a reference for frequency conversion related to a downlink signal directed to a subscriber of the joint reception system. The mobile communication expansion system according to claim 1,
A control signal representing frequency designation information for designating a reference frequency for frequency conversion between the in-system frequency band and the radio frequency band in the second frequency conversion means provided in each subscriber unit is provided in the system. Control signal generating means for generating a signal in a control frequency band different from the frequency band;
Control signal distribution means for superimposing the control signal on the signal of the joint reception system and distributing via the cable wiring;
The reference frequency of the corresponding second frequency converting means is adjusted based on the frequency designation information indicated by the control signal in response to reception of the control signal in the control frequency band provided in each subscriber unit. And a mobile communication expansion system. The mobile communication expansion system according to claim 1,
A reference oscillator that generates a reference oscillation signal having a predetermined frequency that can be transmitted by being superimposed on an empty frequency band of the joint reception system;
A mobile communication extension, comprising: a clock distribution means for supplying the reference oscillation signal as a common reference signal to the first frequency conversion means and the second frequency conversion means via the cable wiring. system.

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