JP5224974B2 - Mobile radio base station - Google Patents

Description

  The present invention relates to a mobile radio base station configured by mounting a (simple) base station typified by a femtocell in an automobile.

  Conventionally, (simple) base stations represented by femtocells that can be installed in homes and stores are known. “Femtocell” refers to an ultra-compact base station connected to a cellular network via a general subscriber line. By using a femtocell, it is difficult to receive radio waves from existing fixed base stations. You can make your mobile phone available in any location.

  FIG. 11 is an explanatory diagram showing an outline of a base station using femtocells. As shown in FIG. 11, a base station 1 using femtocells is installed in a building 2 where radio waves from existing fixed base stations are difficult to reach, and an IP network 4 via a wired broadband line 3 such as ADSL. To the existing mobile phone network (system) 6 via the IP network 4 and the gateway 5. Thereby, the mobile phone 7 in the femtocell area is connected to the mobile phone network 6 via the IP network 4 and can communicate from the inside of the building 2 where radio waves from the fixed base station are difficult to reach.

As such a base station, for example, “mobile communication system and relay apparatus used in this system” (see Patent Document 1) and “mobile communication system, radio switching method, mobile base station, and portable terminal” (patent Focusing on communication at mobile base stations or mobile relay stations mounted on moving bodies such as trains and automobiles, a system that can perform handover between fixed base stations without disconnecting communication has been proposed. ing.
JP-A-9-84126 JP 2004-32155 A

  However, in a conventional system capable of performing handover between fixed base stations, the case where the reception sensitivity of a wireless broadband line connecting between a mobile base station and a communication infrastructure such as a mobile phone network is deteriorated is considered. Not. For example, when the base station 1 using the femtocell is mounted on a car to be a mobile base station, if the car on which the base station 1 is mounted passes through a tunnel or enters an underground parking lot, the base station 1 1 and the communication infrastructure are expected to be disconnected.

  FIG. 12 is a sequence chart showing the order of communication processing of a mobile terminal via a conventional mobile base station. As shown in FIG. 12, for example, a base station using a femto cell is mounted on an automobile to form a mobile base station 1, this mobile base station 1 and a mobile terminal (mobile phone) 7, and further, a mobile base station 1 and a wireless Each of the broadband base stations 8 communicates so that the mobile terminal 7 and the wireless broadband base station 8 can communicate with each other via the mobile base station 1.

  In such a situation, if the reception sensitivity decreases between the mobile base station 1 and the wireless broadband base station 8 and communication is cut off, the mobile terminal 7 and the mobile base station 1 can communicate with each other. Communication between the mobile base station 1 and the wireless broadband base station 8 becomes impossible. That is, when the wireless broadband line is disconnected during communication via the mobile base station 1 using the mobile terminal 7, the mobile terminal 7 is located within the communication range of the mobile base station 1. Communication is not possible.

In addition, even when a vehicle equipped with the mobile base station 1 cannot supply sufficient power to the mobile base station 1 due to, for example, a battery failure, the mobile base station 1 stops operating and the mobile base station 1 1 is expected to be disconnected from the communication infrastructure.
An object of the present invention is to detect in advance that a connection between a mobile terminal that is communicating via a mobile base station and a communication infrastructure is disconnected, and to connect the mobile base station to the mobile terminal connected to the mobile base station. It is to provide a mobile radio base station that can maintain an environment in which a mobile terminal can communicate by handing over to a fixed base station.

To achieve the above object, a mobile radio base station according to the present invention includes a first radio communication unit that performs radio communication with a base station of a first radio communication system, and a radio communication terminal that uses a second radio communication system. and the second wireless communication unit for wireless communication, before SL based on the reception quality of the first radio communication unit, a wireless communication terminal that wireless communication via said second wireless communication unit, the second wireless communication And a control unit for controlling transmission power of the second radio communication unit in order to perform handover to the base station of the system .
In the present invention, it is preferable that the control unit controls the transmission power of the second wireless communication unit to be lowered when the reception quality of the first wireless communication unit is lowered.

A mobile radio base station according to the present invention includes a first radio communication unit that performs radio communication with a base station of a first radio communication system, and a second radio that performs radio communication with a radio communication terminal using the second radio communication system. a communication unit, before SL based on the reception quality of the first radio communication unit, a wireless communication terminal that wireless communication via said second wireless communication unit, a handover to a base station of the second radio communication system And a control unit that collects base station information of the second radio communication system around the local station and controls the base station information to be transmitted to the radio communication terminal via the second radio communication unit. It is said.
In the present invention, it is preferable that the control unit controls the transmission power of the second wireless communication unit to be lowered when the reception quality of the first wireless communication unit is lowered.

  According to the present invention, the mobile base station is informed in advance that the connection between the mobile terminal communicating with the mobile base station and the communication infrastructure is disconnected, and the mobile terminal connected to the mobile base station By handing over from the base station to the fixed base station, it is possible to maintain an environment in which the mobile terminal can communicate.

The best mode for carrying out the present invention will be described below with reference to the drawings.
(First embodiment)
FIG. 1 is a diagram showing a schematic configuration of a radio communication system including a mobile radio base station according to the first embodiment of the present invention. As shown in FIG. 1, a mobile radio base station (hereinafter also referred to as a mobile base station) 10 of the present invention is a femtocell installed in an engine-driven vehicle (hereinafter referred to as an automobile) 11 such as an automobile or a bus. It consists of a base station using

  The mobile base station 10 is wirelessly connected to a wireless broadband base station 13 of a wireless broadband system (first wireless communication system) via a wireless broadband line 12, and the wireless broadband base station 13 includes an IP (Internet Protocol) network 14 and The mobile phone network (second wireless communication system) 16 is connected to the mobile phone network 16 via the gateway 15. As a result, the radio communication terminal (mobile terminal) 17 in the femtocell area is connected to the mobile phone network (system) 16 via the IP network 14 and is more than the existing fixed base station (base station of the mobile phone network). High-speed communication is possible from the inside of the vehicle 11 using a broadband line having a high communication speed. It is assumed that there is a fixed base station 16 a of the second radio communication system 16 around the mobile base station 10.

  In the wireless communication system shown in FIG. 1, for example, a wireless communication terminal (mobile terminal) 17 uses a code division multiple access (CDMA) system as a mobile telephone network line, and the wireless broadband line 12 has a 3. Wireless communication is performed by an LTE (Long Term Evolution) method, which is a wireless communication method called the 9th generation, or a WiMAX (World wide interoperability for Microwave Access) method. In the embodiment, for example, the wireless communication terminal (portable terminal) 17 and the mobile base station 10 are connected by the CDMA system, and the mobile base station 10 and the wireless broadband base station 13 are connected by the LTE system or WiMAX. Connected in a manner.

  FIG. 2 is a block diagram showing a schematic configuration of the mobile radio base station of FIG. As shown in FIG. 2, the mobile base station 10 includes an antenna 18a and a wireless broadband line communication unit for wirelessly communicating with the wireless broadband base station 13 of the first wireless communication system (wireless broadband system via the wireless broadband line 12). (First wireless communication unit) 18, wireless communication unit (second wireless communication unit) 19 and antenna 19 a for wireless communication with wireless communication terminal 17 using second wireless communication system (mobile phone network) 16 , A control unit (Central Processing Unit: CPU) 20 for controlling operations of the wireless broadband line communication unit 18 and the wireless communication unit 19, a RAM (Random Access Memory) 22, a ROM (Read Only Memory). ) And a 21.

  The CPU 20 performs various controls relating to the mobile base station 10 based on software such as a control program stored in the ROM 21, a program defining various processing procedures, various data stored in the RAM 22, and the like. At that time, the CPU 20 connects the wireless communication terminal 17 wirelessly communicating through the wireless communication unit 19 to the mobile phone network 16 through the wireless broadband line communication unit 18 and the wireless broadband line 12 (see FIG. 1). In addition, the transmission power of the wireless communication unit 19 is controlled based on the reception quality of the wireless broadband line communication unit 18, such as reception sensitivity, CIR (Carrier to Interference power Ratio), and throughput.

When controlling the transmission power of the wireless communication unit 19 by the CPU 20, for example, when the reception quality (reception sensitivity, CIR, throughput, etc.) of the wireless broadband line communication unit 18 decreases, the CPU 20 decreases the transmission power of the wireless communication unit 19. To control.
Next, a procedure when the mobile radio base station 10 mounted on the automobile 11 urges the mobile terminal 17 to hand over or instructs the hand-over as the reception sensitivity or throughput of the wireless broadband line 12 deteriorates. explain.

  FIG. 3 is a flowchart showing a flow of handover processing by the mobile radio base station of FIG. As shown in FIG. 3, first, in the mobile radio base station 10, it is determined whether or not there is a change in the reception sensitivity from the wireless broadband base station 13 (step S101). As a result of the determination, if there is no change in the reception sensitivity (No), the determination in step S101 is repeated. On the other hand, if there is a change in the reception sensitivity (Yes), the mobile radio base station 10 The transmission power for the terminal 17 is controlled (step S102). Then, it returns to step S101 and repeats determination.

  FIG. 4 is a sequence chart showing the order of handover processing by the mobile radio base station of FIG. As shown in FIG. 4, when the mobile radio base station 10 that performs radio communication with the mobile terminal 17 by the CDMA system weakens the transmission power as the reception sensitivity of the wireless broadband base station 13 decreases, the mobile radio base station 10 receives it. Thus, the mobile terminal 17 determines a handover of the mobile phone network 16 to the fixed base station 16a (see FIG. 1).

  The mobile terminal 17 that has determined the handover requests the mobile radio base station 10 to disconnect the radio line and requests the fixed base station 16a to connect. The fixed base station 16 a that has received the connection request from the mobile terminal 17 assigns a channel to the mobile terminal 17. The mobile terminal 17 to which the channel is assigned performs handover for switching the connection from the mobile radio base station 10 to the fixed base station 16a by the assigned channel, and performs radio communication with the fixed base station 16a of the mobile phone network 16. Do.

  That is, when the mobile radio base station 10 detects a change in LTE reception sensitivity or throughput in communication with the wireless broadband network, the mobile radio base station 10 is synchronized with the deterioration in LTE reception sensitivity or throughput. The mobile terminal 17 controls the transmission power to the mobile terminal 17 and searches the mobile terminal 17 that is a CDMA terminal for a CDMA fixed base station that is actively located in the vicinity of the mobile terminal 17 by itself. The mobile phone network 16 as a base station is prompted to perform a handover to the fixed base station 16a.

When the reception quality deteriorates, the mobile radio base station 10 controls the transmission power, and the CPU 20 lowers the transmission power of the radio communication unit 19, that is, the mobile radio base station 10 narrows the communication area, so that the mobile terminal 17 Is handed over to the fixed base station 16a of the mobile phone network 16 being monitored.
If the reception sensitivity or throughput deterioration is recovered before handover after the LTE reception sensitivity or throughput deterioration, the mobile radio base station 10 increases the transmission power. Therefore, the reception sensitivity of the mobile radio base station 10 in the mobile terminal is increased. And the handover is not performed.

  The above description is a case where the mobile terminal 17 and the mobile radio base station 10 are communicating, but the present invention can be applied not only during communication but also during standby (standby). During standby, by using the location registration at the time of standby, when it is likely to disconnect, neighboring base station information is received and the connection destination is determined from the information.

  In this way, in an environment where the mobile terminal 17 possessed by the user in the car 11 is connected to the mobile radio base station 10 mounted on the car 11, the mobile radio base station 10 is wirelessly connected via the wireless broadband line 12. It is detected in advance that communication with the wireless broadband base station 13 of the broadband network becomes impossible, and the mobile terminal 17 is handed over from the mobile radio base station 10 to the fixed base station 16a of the mobile phone network 16 (see FIG. 1). Thus, an environment where the mobile terminal 17 can communicate can be maintained.

  That is, in the mobile base station using the conventional femtocell, if the reception sensitivity of the LTE base station to which the mobile base station is currently connected deteriorates and another LTE base station that is a handover candidate cannot be found, communication is not possible. It was in a state where it was not possible. The CDMA terminal (mobile terminal) is in an environment where communication is possible because it is determined that the mobile base station is within range, but communication is not actually possible. This is because the mobile base station continues to function as a base station even when communication with a communication infrastructure (for example, a wireless broadband network) becomes impossible due to being out of service area. The CDMA terminal that is in the range display cannot communicate.

(Second Embodiment)
FIG. 5 is a block diagram showing a schematic configuration of a mobile radio base station according to the second embodiment of the present invention. As shown in FIG. 5, the mobile radio base station 30 includes a wireless broadband line communication unit 18, a radio communication unit 19, a CPU 20, a RAM 22, a neighboring base station search radio communication unit 31, and a ROM 32. Except for having the station search radio communication unit 31 and the ROM 32 instead of the ROM 21, it has the same configuration and operation as the mobile radio base station 10 according to the first embodiment.

  The neighboring base station search radio communication unit 31 includes an antenna 31a, searches for a base station of a cellular phone network located in the vicinity, and communicates with a neighboring base station based on the search result. In addition to the various function programs in the ROM 21, the ROM 32 stores a neighboring base station search function program for searching for neighboring base stations and an engine stop detection function program for detecting engine stop.

  In the mobile radio base station 30, the CPU 20 collects base station information of a radio communication system using a mobile phone network around the local station (mobile radio base station 30) when the reception quality of the wireless broadband line communication unit 18 decreases. Then, the data is transmitted to the mobile terminal 17 via the wireless communication unit 19 and the transmission power of the wireless communication unit 19 is reduced. That is, the CPU 20 causes the mobile terminal 17 to monitor the fixed base station 16a of the mobile phone network 16 in the vicinity of the own station that the mobile terminal 17 has not monitored.

A procedure when the mobile radio base station 30 mounted on the automobile 11 prompts the portable terminal 17 to perform handover or instructs handover when the LTE reception sensitivity or throughput deterioration is detected will be described.
FIG. 6 is a flowchart showing the flow of handover processing (part 1) by the mobile radio base station of FIG. As shown in FIG. 6, first, in the mobile radio base station 30 using a femtocell, it is determined whether or not the broadband reception sensitivity in the femtocell is smaller than a threshold (reception sensitivity <threshold) (step S201).

If the reception sensitivity is not smaller than the threshold (No) as a result of the determination, the determination in step S201 is repeated. On the other hand, if the reception sensitivity is smaller than the threshold (Yes), the mobile radio base station 30 Fixed base station information is collected (step S202).
After collecting the neighboring fixed base station information, the mobile radio base station 30 sends the collected neighboring fixed base station information to the portable terminal 17 and instructs the portable terminal 17 to perform a handover (step S203). Thereafter, the process ends.

  FIG. 7 is a sequence chart showing the order of the handover process (part 1) by the mobile radio base station of FIG. As shown in FIG. 7, when the mobile radio base station 30 performing radio communication with the mobile terminal 17 by the CDMA system weakens the transmission power as the reception sensitivity decreases, The station 30 collects information related to the fixed base station 16 a of the mobile phone network 16 located in the vicinity of the mobile radio base station 30. After the collection, the mobile radio base station 30 instructs the portable terminal 17 to perform a handover to the fixed base station 16a together with information on the collection result.

  The mobile terminal 17 that has determined the fixed base station 16a as the handover destination based on the information acquired from the mobile radio base station 30 requests the mobile radio base station 30 to disconnect the radio line and selects (determines) the fixed base station. A connection request is made to the base station 16a. The fixed base station 16 a that has received the connection request from the mobile terminal 17 assigns a channel to the mobile terminal 17. The mobile terminal 17 to which the channel is assigned performs wireless communication with the fixed base station 16a of the mobile phone network 16 through the assigned channel.

  As described above, when the mobile radio base station 30 detects deterioration of LTE reception sensitivity or throughput, the mobile radio base station 30 searches for the fixed base station 16a of the cellular phone network 16 that is a neighboring CDMA fixed base station, and is a CDMA terminal. The portable terminal 17 is instructed to transmit the searched information and perform handover to the fixed base station 16a.

  That is, in an environment where the mobile terminal 17 possessed by a user in the car 11 is connected to the mobile radio base station 30 mounted on the car 11, the mobile radio base station 30 is connected to the wireless broadband line 12. Detecting beforehand that communication with the wireless broadband base station 13 of the network becomes impossible, searches for the fixed base station 16a of the nearby mobile phone network 16, and transmits the search information to the mobile terminal 17 to By handing over to the station 16a, even when the mobile terminal 17 is connected to the mobile radio base station 30, it is possible to perform handover smoothly and communicate even if the base station information of the mobile phone network is not acquired. Help maintain the environment.

  The mobile radio base station 30 stops the function of the mobile radio base station 30 even when the engine of the automobile 11 is stopped. Therefore, the mobile radio base station 30 is not limited to the case where the deterioration of LTE reception sensitivity or throughput is detected. And when the state leading to the engine stop is detected, the portable terminal 17 is instructed to be handed over.

(Third embodiment)
Next, when a plurality of portable terminals are connected to the mobile radio base station 30 mounted on the automobile 11, the mobile radio base station 30 detects a deterioration in LTE reception sensitivity or throughput. A procedure for limiting the number of possible portable terminals 17 and prompting the restricted portable terminal 17 to perform handover or instructing handover will be described.

  A plurality of mobile terminals, for example, a first mobile terminal 17a and a second mobile terminal 17b, are connected to the mobile radio base station 30, and the first mobile terminal 17a and the second mobile terminal 17b are respectively connected to the mobile radio base station 30. Communicating with the station 30. The connection priority between the first portable terminal 17a and the second portable terminal 17b is higher for the first portable terminal 17a (for example, a car owner user) and for the second portable terminal 17b (for example, a guest user). Is assumed to be low.

  FIG. 8 is a flowchart showing the flow of the handover process (part 2) by the mobile radio base station of FIG. 5 according to the third embodiment of the present invention. As shown in FIG. 8, first, in the mobile radio base station 30, it is determined whether or not the broadband throughput in the femtocell has decreased (step S301). As a result of the determination, if the throughput has not decreased (No), the determination in step S301 is repeated. On the other hand, if the throughput has decreased (Yes), the mobile radio base station 30 can permit connection. It is determined whether or not the number of terminals, that is, the allowable number of connections is reduced (step S302).

  As a result of the determination in step S302, if the allowable connection number has not decreased (No), the process returns to step S301 to repeat the determination. On the other hand, if the allowable connection number has decreased (Yes), the mobile type Among the mobile terminals connected to the radio base station 30, a mobile terminal to be excluded is determined (step S303). In the determination, the mobile terminal 17b with the lower connection priority is excluded.

  Thereafter, the mobile radio base station 30 collects the fixed base station information of the neighboring mobile phone network 16 (step S304), and after collecting, sends the collected neighboring fixed base station information to the mobile terminal 17b to be excluded. The handover is instructed to the mobile terminal 17b to be excluded (step S305). Then, it returns to step S301 and repeats determination.

  FIG. 9 is a sequence chart showing the order of the handover process (part 2) by the mobile radio base station of FIG. As shown in FIG. 9, the mobile radio base station 30 that performs radio communication by the CDMA system with each of the first mobile terminal 17a and the second mobile terminal 17b is a mobile terminal that can be accommodated as throughput decreases. Limit the number. In restricting the number, for example, the connection priorities of the first mobile terminal 17a and the second mobile terminal 17b are compared, and the mobile terminal 17b having a lower connection priority is excluded.

  After the mobile radio base station 30 decides to exclude the mobile terminal 17b, the mobile radio base station 30 collects information about the fixed base station 16a of the mobile phone network 16 located in the vicinity, and collects the collected information about the fixed base stations in the vicinity. The data is sent to the terminal 17b and the handover is instructed to the mobile terminal 17b to be excluded.

The mobile terminal 17b that has decided to hand over the fixed base station 16a of the mobile phone network 16 located in the vicinity requests the mobile radio base station 30 to disconnect the radio line and connects to the selected fixed base station 16a. Request. The fixed base station 16a that has received the connection request from the portable terminal 17b performs channel allocation to the portable terminal 17b. The mobile terminal 17b to which the channel is assigned performs radio communication with the fixed base station 16a through the assigned channel.
Note that the mobile terminal 17a that has a high connection priority and is not instructed to perform handover continues to connect to the mobile radio base station 30 and continue communication.

  As described above, when the mobile radio base station 30 detects deterioration of LTE reception sensitivity or throughput, the mobile radio base station 30 controls to limit the number of portable terminals 17 that can be accommodated, and at the same time, fixes the neighboring CDMAs. The fixed base station 16a of the mobile phone network 16 that is the base station is searched, information about the fixed base station 16a is notified to the mobile terminal 17b that is the CDMA terminal that is subject to restriction, and the mobile phone that is subject to restriction. The terminal 17b instructs to hand over to the fixed base station 16a actively located nearby.

(Fourth embodiment)
FIG. 10 is an explanatory diagram showing a communication system using a mobile radio base station according to the fourth embodiment of the present invention. As shown in FIG. 10, the mobile radio base station 35 is connected to the wireless broadband line communication unit 18, the radio communication unit 19, the CPU 20, the neighboring base station search radio communication unit 31, the ROM 32, the external interface 36, the RAM 37, and the automobile 11. It has the same car navigation system 11a, and has the same configuration and operation as the mobile radio base station 30 according to the second embodiment, except that it has an external interface 36 and a RAM 37 instead of the RAM 22. ing.

  The external interface 36 is connected to a car navigation system 11a provided in the automobile 11, and the mobile radio base station 35 obtains global positioning system (GPS) information from the car navigation system 11a. be able to. In addition to the storage area of the RAM 22, the RAM 37 has a mobile terminal storage area for storing usage frequency information and registration information regarding the mobile terminal 17.

  As described above, since the mobile radio base station 35 can obtain GPS information from the car navigation system 11a, when the mobile radio base station 35 searches for a base station of a nearby mobile phone network, the GPS Based on the information, information for search may be inquired to the server through the wireless broadband line 12. Further, based on the GPS information, the mobile radio base station 35 may search for a nearby wireless broadband base station.

(Fifth embodiment)
Next, another example of instructing handover will be described.
A case where a handover is instructed for a plurality of CDMA terminals (mobile terminals 17) will be described.
The CPU 20 of the mobile radio base station (10, 30) has a function of determining the order to be handed over according to the priority order of each portable terminal 17, and the storage means (RAM) of the mobile radio base station. In addition, an area for storing pre-registered mobile terminal identification information, connection frequency, and the like is provided. The order of handover is determined based on the information regarding the identification information, connection frequency, etc. of the mobile terminal that gives the highest priority to the mobile terminal currently in communication or has been registered in advance.

For example, as shown in a sequence chart (see FIG. 9) showing the order of handover processing by the mobile radio base station, the priority order of the first mobile terminal 17a is higher than the priority order of the second mobile terminal 17b. The mobile radio base station hands over and eliminates the second portable terminal 17b having a low priority as the throughput decreases.
In addition, when the LTE reception sensitivity or throughput deteriorates and the engine of the automobile 11 stops before the handover is performed, it is determined that the LTE reception sensitivity cannot be recovered due to the movement of the automobile 11, and the mobile radio base The station immediately instructs the portable terminal 17 to perform handover (see FIG. 6).

  As described above, the mobile radio base station (mobile base station) according to the present invention detects a deterioration in the reception sensitivity of the wireless broadband line, a decrease in throughput, an increase in the number of connected units, power supply (engine stoppage, etc.), The following processing is performed.

1. Controls the transmission power of the mobile base station. By reducing the transmission power, the mobile terminal itself is urged to actively perform handover.
2. The mobile base station collects and transmits information on a fixed base station of a nearby mobile phone network to the mobile terminal to instruct a handover.
3. The mobile base station limits the number of mobile terminals that can be accommodated, and instructs the restricted mobile terminals to perform handover to a fixed base station in a nearby mobile phone network.

The mobile base station has the following functions.
1. 2. And 3. In this case, when there are a plurality of portable terminals in the automobile, the mobile base station determines the priority of the portable terminals and considers the order of instructing handover. A function for storing information such as identification information and frequency of use of the mobile terminal so that the mobile base station can determine the priority order.

2. In an environment where the reception sensitivity or throughput of the wireless broadband line connecting the mobile base station and the communication infrastructure is poor, if another wireless broadband base station to be handed over is not found, the mobile base station A function of detecting, judging that recovery of reception sensitivity or throughput due to movement cannot be expected, and instructing a handover to a fixed base station of a cellular phone network.
The mobile base station may be composed of a fixed base station and an in-vehicle module having a wireless broadband communication function. In addition, the mobile base station may have a function of searching for a fixed base station in a nearby mobile phone network, for example, a function of connecting to a network system built in an automobile such as a car navigation system. .

  The mobile radio base station (mobile base station) according to the present invention has the above-described configuration, so that the automobile is connected to the mobile base station installed in the automobile by using the wireless broadband line. An environment in which the mobile terminal can communicate can be maintained by detecting in advance that communication is impossible and handing over the mobile terminal from the mobile base station to the fixed base station of the mobile phone network.

  In the processing system in the mobile radio base station according to the present invention, a storage device is connected to a programmed main control unit (CPU) that performs overall control of the entire system. It has a program that defines the processing procedure and an internal memory for storing required data, and the various means described above are realized by these programs.

  In addition, although this invention was demonstrated by embodiment mentioned above, it is not limited to this embodiment. Therefore, what is implemented as a change aspect without deviating from the meaning of the present invention is also included. For example, the present invention is not limited to a mobile phone, and can be applied to a mobile terminal device other than a mobile phone.

It is explanatory drawing which shows the communication system by the mobile radio | wireless base station which concerns on 1st Embodiment of this invention. It is a block diagram which shows schematic structure of the mobile radio base station of FIG. 2 is a flowchart showing a flow of handover processing by the mobile radio base station of FIG. 1. 3 is a sequence chart showing the order of handover processing by the mobile radio base station of FIG. 1. It is a block diagram which shows schematic structure of the mobile radio | wireless base station which concerns on 2nd Embodiment of this invention. 6 is a flowchart showing a flow of handover processing (part 1) by the mobile radio base station of FIG. 6 is a sequence chart showing the order of handover processing (part 1) by the mobile radio base station of FIG. It is a flowchart which shows the flow of the hand-over process (the 2) by the mobile radio | wireless base station of FIG. 5 based on 3rd Embodiment of this invention. FIG. 9 is a sequence chart showing the order of handover processing (part 2) by the mobile radio base station of FIG. 8. It is explanatory drawing which shows the communication system by the mobile radio | wireless base station which concerns on 4th Embodiment of this invention. It is explanatory drawing which shows the outline | summary of the base station using a femtocell. It is a sequence chart which shows the order of the communication processing of the portable terminal via the conventional mobile base station.

Explanation of symbols

10, 30, 35 Mobile radio base station 11 Car 11a Car navigation system 12 Wireless broadband line 13 Wireless broadband base station 14 IP network 15 Gateway 16 Mobile phone network 16a Fixed base station 17 Mobile terminal 17a First mobile terminal 17b 2nd mobile phone Terminal 18 Wireless broadband line communication unit 18a, 19a, 31a Antenna 19 Wireless communication unit 20 CPU
21,32 ROM
22, 37 RAM
31 Neighboring base station search radio communication part 36 External interface

Claims (4)

A first wireless communication unit that wirelessly communicates with a base station of the first wireless communication system;
A second wireless communication unit that wirelessly communicates with a wireless communication terminal that uses the second wireless communication system;
Before SL based on the reception quality of the first radio communication unit, for a wireless communication terminal that wireless communication via said second wireless communication unit, a handover to a base station of the second radio communication system, wherein And a control unit that controls transmission power of the second radio communication unit.   The mobile radio base station according to claim 1, wherein the control unit controls the transmission power of the second radio communication unit to be lowered when reception quality of the first radio communication unit is lowered. A first wireless communication unit that wirelessly communicates with a base station of the first wireless communication system;
A second wireless communication unit that wirelessly communicates with a wireless communication terminal that uses the second wireless communication system;
Before SL based on the reception quality of the first radio communication unit, for a wireless communication terminal that wireless communication via said second wireless communication unit, a handover to a base station of the second wireless communication system, the self A control unit that collects base station information of the second radio communication system around the station and controls the base station information to be transmitted to the radio communication terminal via the second radio communication unit. Radio base station.   The mobile radio base station according to claim 3, wherein the control unit controls the transmission power of the second radio communication unit to be lowered when the reception quality of the first radio communication unit is lowered.

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