JP4748106B2 - Antenna beam control method, antenna beam control apparatus, and mobile communication system - Google Patents

Description

  The present invention relates to an antenna beam control method, an antenna beam control apparatus, and a mobile communication system, and more particularly, to an antenna beam control method, an antenna beam control apparatus, and a mobile communication system of a radio base station using mobile radio position information.

  In mobile radio systems based on code division multiple access (CDMA), orthogonal codes are assigned to each mobile radio terminal and communication is performed using the same frequency, so communication quality is improved and frequency utilization efficiency is improved. For this purpose, the base station performs communication using the directivity control of the adaptive antenna. In this adaptive antenna, a plurality of antenna elements are regularly arranged, and in reception, different amplitude and phase components obtained through the respective antenna elements are weighted to form a spatial filter, and in transmission, an appropriate amplitude is obtained. -Arbitrary directivity characteristics in antenna radiation are formed by weighting phase components.

  In this CDMA mobile communication system, switching (handoff) of a base station to be connected to a radio line is performed as the mobile radio terminal moves. In this case, before the mobile radio terminal switches communication from the handoff source base station to the handoff destination base station, communication can be performed simultaneously with the two base stations. However, since the base station of the handoff destination does not know the direction of the mobile radio terminal, it is impossible to form a sharp directivity (a beam pattern with a small half-angle value) toward the mobile radio terminal from the beginning. For this reason, since the handoff destination base station takes a method such as starting communication on the downlink for all directions, there is a problem that highly efficient communication cannot be performed from the initial stage of communication.

  Therefore, based on the installation position information of each base station of the handoff and the base station of the handoff and the directivity control information of the uplink of the base station of the handoff, the base station of the handoff There is already a mobile communication system that improves the communication quality of the uplink of the handoff destination base station at the time of handoff activation by determining the initial directivity control parameter of the uplink and forming the initial directivity in advance. It has been proposed (see, for example, Patent Document 1).

  In addition, a cellular phone that can be connected to either a cellular wireless network or a wireless local area network (LAN), a backbone network to which an information server is connected, and a first gateway connected to the backbone network via a first gateway. A mobile phone company base station connected to the first subnet, a second subnet connected to the backbone network via a second gateway, and a radio connected to the second subnet In a wireless communication system equipped with an access point of a LAN operator, when the mobile phone is located outside the communication range of the access point, the access point is controlled by controlling the directivity of the access point so that the mobile phone can communicate with the access point. Connect your mobile phone to a wireless LAN without moving your points It is known also wear a mobile communication system (e.g., see Patent Document 2).

JP 2000-244386 A JP 2005-026857 A

  Here, the mobile communication system can be roughly divided into a cellular radio network and a radio local area network (wireless LAN). The cellular radio network is a CDMA mobile communication system described in Patent Document 1 described above, in which a service area is divided into a plurality of cells, and a radio base station is arranged at the center of each cell. Is connected to the upper station. This mobile radio terminal can move while communicating with the nearest radio base station and further communicating with a partner terminal connected to the public network via a host station, and moves from one cell to another. In this case, the above-described handover is performed and communication is continued.

  On the other hand, a wireless LAN is a system in which a mobile wireless terminal can wirelessly communicate with a wireless LAN base station according to a protocol such as 802.11 of the Institute of Electrical and Electronics Engineers (IEEE). A wireless LAN is more suitable for large-capacity data transmission than a cellular wireless network. When a mobile wireless terminal moves between two different wireless networks such as a cellular wireless network and a wireless LAN, the mobile wireless terminal switches communication between wireless base stations of different wireless networks and continues communication. You need to be able to roam.

  In the mobile communication system described in Patent Document 1, when a mobile radio terminal moves from one cell to another cell in the same cellular radio network, the installation position information of the base station in one cell and the destination cell of another cell Since the base station installation position information is known, the handoff destination base station can estimate the direction of the mobile radio terminal from its own station and control its antenna beam.

  However, when the mobile wireless terminal moves from the cellular wireless network to the wireless LAN, the base station in the wireless LAN cannot obtain the installation location information of the base station of the cellular wireless network of the movement source in advance. The base station cannot estimate the direction of the mobile radio terminal and cannot perform highly efficient communication from the initial stage of communication.

  The mobile communication system described in Patent Document 2 controls the directivity of an access point so that a mobile phone that can be connected to either a cellular wireless network or a wireless LAN can communicate with an access point of a wireless LAN operator. Thus, the mobile phone can be connected to the wireless LAN without moving the access point, and after starting communication with the access point, the wireless LAN base station determines the position of the mobile wireless terminal and directs the antenna beam. There is a problem that the configuration of the wireless LAN base station for determining the frequency is relatively complicated.

  The present invention has been made in view of the above points. When a mobile wireless terminal moves from a cellular wireless network to a wireless LAN, communication efficiency between the wireless LAN base station and the mobile wireless terminal is improved. It is an object of the present invention to provide an antenna beam control method, an antenna beam control apparatus, and a mobile communication system that can realize simplification.

In order to achieve the above object, a first invention is an antenna beam control method for a wireless LAN base station installed in a wireless LAN network, the mobile wireless base station installed in a cellular wireless network, and a mobile wireless A first estimating step for estimating a distance and an azimuth angle from the mobile radio base station to the mobile radio terminal when the terminal is performing radio communication; and each of the wireless LAN base stations installed in the wireless LAN network A first notification step of notifying the installation location information of the mobile radio base station to a database device in which the installation location information is stored in advance, and a wireless LAN base station in which the installation location information is stored in the database device, The database device is installed around the mobile radio base station based on the location information of the mobile radio base station notified in the notification step 1. A second notification step of acquiring the location information of the wireless base station being informed and notifying the mobile radio base station; and a second notification step in which the mobile radio base station has its own location information of the mobile radio base station The second estimation for estimating the distance and azimuth from the mobile radio base station to the radio LAN base station notified in the second notification step using the installation location information of the wireless LAN base station notified in The distance and azimuth angle from the mobile radio base station to the wireless LAN base station estimated in the step, the second estimation step, and the distance and azimuth angle from the mobile radio base station to the mobile radio terminal estimated in the first estimation step. And a third estimation step for estimating a distance and an azimuth angle from the wireless LAN base station to the mobile radio terminal, and a mobile radio terminal whose distance and azimuth angle are estimated in the third estimation step. Characterized in that it comprises a control step of controlling so as to direct the direction of the antenna beam of the wireless LAN base station.

In order to achieve the above object, a second invention is an antenna beam control apparatus for a wireless LAN base station installed in a wireless LAN network, comprising: a mobile wireless base station installed in a cellular wireless network; A first estimation means for estimating a distance and an azimuth angle from the mobile radio base station to the mobile radio terminal when the mobile radio terminal is performing radio communication; and a wireless LAN base station installed in the wireless LAN network A database device in which each installation location information is stored in advance, a first notification means for notifying the database device of the installation location information of the mobile radio base station, and a wireless LAN base in which the installation location information is stored in the database device The mobile radio base station is installed around the mobile radio base station based on the location information of the mobile radio base station notified by the first notification means. A second notifying unit for acquiring the location information of the wireless LAN base station and notifying the mobile radio base station; and the location information of the mobile radio base station and the location of the wireless LAN base station notified by the second notifying unit Second estimation means for estimating the distance and azimuth from the mobile radio base station to the wireless LAN base station notified by the second notification means using the position information, and estimation by the second estimation means Using the distance and azimuth angle from the mobile radio base station to the wireless LAN base station and the distance and azimuth angle from the mobile radio base station to the mobile radio terminal estimated by the first estimating means, Direction of the antenna beam of the wireless LAN base station in the direction of the mobile wireless terminal for which the distance and the azimuth are estimated by the third estimating means; be controlled so as to direct the And having an antenna beam direction control means.

Furthermore, in order to achieve the above object, the third invention is any one of a wireless LAN base station installed in a wireless LAN network by roaming and a mobile wireless base station installed in a cellular wireless network. A mobile communication system comprising a database device that performs wireless communication between the mobile wireless terminal and the wireless LAN base station installed in the wireless LAN network, in which installation position information of each wireless LAN base station is stored in advance .
The database device acquires installation location information of wireless LAN base stations installed around the mobile radio base station based on the notified installation location information of the mobile radio base station and notifies the mobile radio base station It has installation location information notification means,
The mobile radio base station, when wirelessly communicating with the mobile radio terminal, a first estimation means for estimating the distance and azimuth angle from the mobile station to the mobile radio terminal, installation position information of the mobile station, A second method for estimating the distance and azimuth from the own station to the wireless LAN base station notified by the installation position information notification means using the installation position information of the wireless LAN base station notified by the installation position information notification means And the distance and azimuth angle from the local station to the wireless LAN base station estimated by the second estimation means, and the distance and azimuth angle from the local station to the mobile radio terminal estimated by the first estimation means. And a third estimating means for estimating the distance and azimuth from the wireless LAN base station to the mobile wireless terminal and notifying the wireless LAN base station,
Based on the distance and azimuth angle notified from the mobile radio base station, the wireless LAN base station directs the direction of the antenna beam of the local station to the direction of the mobile radio terminal whose distance and azimuth angle are estimated. and having an antenna beam direction control means for controlling the.

  ADVANTAGE OF THE INVENTION According to this invention, while a wireless LAN base station can communicate efficiently with the mobile wireless terminal which was communicating with the mobile wireless base station until now from the initial stage of communication, a wireless LAN base station is a mobile wireless terminal. By obtaining the position information from the mobile radio base station, it is possible to eliminate the function of determining the position by itself and determining the direction in which the antenna beam is directed, and to simplify the configuration.

  Next, the best mode for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 shows a configuration diagram of an embodiment of a mobile communication system according to the present invention. As shown in FIG. 1, the mobile communication system of this embodiment includes a wireless LAN base station 1, a mobile radio base station 3, a mobile radio terminal 5, and a database device 9.

  The wireless LAN base station 1 is one wireless base station in the wireless LAN, and performs wireless communication 11 with the mobile wireless terminal 5 within the communication range 2 of the wireless LAN base station 1. The mobile radio base station 3 is one radio base station in the cellular radio network, and performs radio communication 10 with the mobile radio terminal 5 within the communication range 4 of the mobile radio base station 3.

  In addition, the mobile radio base station 3 communicates the wireless LAN base station position information 7 and the mobile radio base station position information 8 with the database device 9 by wire, and the mobile radio terminal station 1 communicates with the wireless LAN base station 1. Information 6 is communicated by wire. The wireless LAN base station 1 performs wireless communication 11 from the wireless LAN base station 1 to the mobile wireless terminal 5 with the antenna beam directed toward the mobile wireless terminal 5 in accordance with the mobile wireless terminal position information 6. In the database device 9, installation position information of the wireless LAN base station 1 is registered in advance.

  According to the present embodiment, with such a configuration, the wireless LAN base station 1 can direct the antenna beam to the mobile radio terminal 5 before starting communication with the mobile radio terminal 5, and the antenna beam direction during communication. Correction is performed.

  Next, the operation of the present embodiment using the position information of mobile radio, that is, the antenna beam control method of the wireless LAN base station will be described with reference to the configuration diagram of FIG. 1 and the flowchart of FIG. If the mobile radio terminal 5 is located within the communication range 4 of the mobile radio base station 3 but is not located within the communication range 2 of the wireless LAN base station 1, the mobile radio base station 3 Radio communication 10 is performed with the mobile radio terminal 5 to estimate the distance and azimuth from the mobile radio base station 3 to the mobile radio terminal 5 (step S1). This estimation method is well known to those skilled in the art in a mobile communication system with a general mobile radio base station 3 and a mobile radio terminal 5, and since it is not directly related to the present invention, its detailed configuration is omitted. To do.

  Next, the mobile radio base station 3 notifies the database apparatus 9 of the installation position of the mobile radio base station 3 as mobile radio base station position information 8 (step S2). The installation position information of the mobile radio base station 3 is registered in the mobile radio base station 3 itself at the time of installation, or a GPS signal is received by a GPS (Global Positioning System) receiver of the mobile radio base station 3 and publicly known. Get in the way.

  In the database device 9, installation position information of the wireless LAN base station 1 is registered in advance. The database device 9 is installed around the mobile radio base station 3 from among a plurality of installed wireless LAN base stations using the mobile radio base station position information 8 notified from the mobile radio base station 3. The wireless LAN base station 1 is selected (step S3). Subsequently, the database device 9 notifies the mobile radio base station 3 of the installation position information of the selected wireless LAN base station 1 as the wireless LAN base station position information 7 (step S4).

  The mobile radio base station 3 uses the wireless LAN base station position information 7 notified from the database device 9 and the distance and azimuth angle estimation information from the mobile radio base station 3 to the mobile radio terminal 5 estimated in step S1. The distance from the wireless LAN base station 1 to the mobile wireless terminal 5 and the azimuth angle are estimated and notified to the wireless LAN base station 1 as mobile wireless terminal position information 6 (step S5).

  The estimation of the mobile radio terminal location information 6 in step S5 is performed as follows. The mobile radio base station 3 first estimates the distance and azimuth from the mobile radio base station 3 to the wireless LAN base station 1 using the installation location information of the own device and the installation location information of the wireless LAN base station 1. . Then, the distance and azimuth angle from the wireless LAN base station 1 to the mobile radio terminal 5 are estimated using the distance and azimuth information from the mobile radio base station 3 to the mobile radio terminal 5.

  Further, by estimating the information of the antenna height of the mobile radio base station 3 and the antenna height of the radio LAN base station 1 together with the distance and the azimuth angle, the mobile radio base station 1 moves to the mobile radio terminal. It is also possible to estimate the distance up to 5, the azimuth angle, and the depression angle.

  Next, the wireless LAN base station 1 directs the antenna beam toward the mobile wireless terminal 5 whose distance and azimuth are estimated according to the mobile wireless terminal position information 6 notified from the mobile wireless base station 3 (step S6). ). With this operation, the wireless LAN base station 1 can direct the antenna beam toward the mobile radio terminal 5 before starting communication with the mobile radio terminal 5. Thereafter, the wireless communication 11 is started with the mobile wireless terminal 5 when the mobile wireless terminal 5 enters the communication range 2 of the wireless LAN base station 1.

  As described above, according to the present embodiment, before the wireless LAN base station 1 starts communication with the mobile radio terminal 5, the position of the mobile radio terminal 5 can be known and the direction in which the antenna beam is directed can be determined. Thus, highly efficient communication is possible from the initial stage of wireless communication between the wireless LAN base station 1 and the mobile wireless terminal 5.

  Further, according to the present embodiment, after the start of wireless communication between the wireless LAN base station 1 and the mobile wireless terminal 5, the wireless LAN base station 1 obtains the position information of the mobile wireless terminal 5 from the mobile wireless base station 3. Therefore, the function of determining the position of the antenna beam by determining the position by itself is unnecessary, and the configuration of the wireless LAN base station 1 can be simplified.

  Note that by adding a function of notifying the mobile radio terminal 5 of the information estimated by the mobile radio base station 3, the mobile radio terminal 5 transmits an antenna to the radio LAN base station 1 before starting communication with the radio LAN base station 1. It is also possible to direct the beam. Further, during communication between the wireless LAN base station 1 and the mobile wireless terminal 5, this operation is performed to sequentially estimate the distance and azimuth angle from the wireless LAN base station 1 to the mobile wireless terminal 5, so that the wireless LAN base station It is also possible to correct the antenna beam direction of 1 and / or the mobile radio terminal 5.

  The present invention is not limited to the above embodiment. For example, in the above embodiment, a method for performing estimation by the mobile radio base station 3 is described. Thus, the database device 9 can also estimate the distance, azimuth angle, and depression angle from the wireless LAN base station 1 to the mobile wireless terminal 5.

It is a block diagram of one Example of the mobile communication system of this invention. It is a flowchart of one Example of the antenna beam control method of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wireless LAN base station 2 Wireless LAN base station communication range 3 Mobile wireless base station 4 Mobile wireless base station communication range 5 Mobile wireless terminal 6 Mobile wireless terminal location information 7 Wireless LAN base station location information 8 Mobile wireless base station location information 9 Database equipment

Claims (9)

An antenna beam control method for a wireless LAN base station installed in a wireless LAN network,
When the mobile radio base station installed in a cellular radio network and a mobile radio terminal is a wireless communication, a first estimation for estimating the distance and azimuth to the mobile radio terminal from the mobile radio base station Steps,
A first notifying step of notifying the installation position information of the mobile radio base station to a database device in which the installation position information of each of the wireless LAN base stations installed in the wireless LAN network is stored in advance;
Based on the installation location information of the mobile radio base station notified in the first notification step from the wireless LAN base stations whose installation location information is stored in the database device, the database device A second notification step of acquiring installation location information of a wireless LAN base station installed around a mobile radio base station and notifying the mobile radio base station;
The mobile radio base station uses the installation location information of its mobile radio base station and the installation location information of the wireless LAN base station notified in the second notification step from the mobile radio base station. A second estimation step of estimating the distance to the wireless LAN base station and the azimuth angle notified in the notification step of 2,
The distance and azimuth angle from the mobile radio base station to the wireless LAN base station estimated in the second estimation step, and the distance from the mobile radio base station to the mobile radio terminal estimated in the first estimation step And a third estimation step for estimating a distance and an azimuth angle from the wireless LAN base station to the mobile radio terminal using the azimuth angle and the azimuth angle;
And a control step of controlling the direction of the antenna beam of the wireless LAN base station toward the direction of the mobile wireless terminal whose distance and azimuth are estimated in the third estimation step. Antenna beam control method. After the antenna beam is controlled in the control step , communication between the wireless LAN base station and the mobile wireless terminal is started when the mobile wireless terminal enters the communication range of the wireless LAN base station. antenna beam controlling method according to claim 1, characterized in that it comprises a communication starting step. A third notification step of notifying the distance and azimuth from the wireless LAN base station estimated in the third estimation step to said mobile radio terminal to the mobile radio terminal, the distance in the third notification step the mobile radio terminal away and the azimuth is notified, according to claim 1 or, characterized in that the further including a direction of an antenna beam of a mobile radio terminal and a beam direction control step of directing said wireless LAN base station direction 3. The antenna beam control method according to 2. An antenna beam control device for a wireless LAN base station installed in a wireless LAN network,
First estimation for estimating a distance and an azimuth from the mobile radio base station to the mobile radio terminal when the mobile radio base station installed in the cellular radio network and the mobile radio terminal are performing radio communication Means,
A database device in which installation location information of each of the wireless LAN base stations installed in the wireless LAN network is stored in advance;
First notification means for notifying the database device of installation location information of the mobile radio base station;
Based on the installation location information of the mobile radio base station notified by the first notification means from among the wireless LAN base stations whose installation location information is stored in the database device, the mobile radio base station Second notification means for acquiring installation location information of wireless LAN base stations installed in the vicinity and notifying the mobile radio base station;
Using the location information of the mobile radio base station and the location information of the wireless LAN base station notified by the second notification means, the mobile radio base station notified by the second notification means Second estimating means for estimating a distance and an azimuth angle to the wireless LAN base station;
The distance and azimuth angle from the mobile radio base station to the wireless LAN base station estimated by the second estimation means, and the distance from the mobile radio base station to the mobile radio terminal estimated by the first estimation means And a third estimation means for estimating a distance and an azimuth from the wireless LAN base station to the mobile radio terminal using the azimuth and
And a antenna beam direction control means for controlling so as to direct the direction of the antenna beam of said third of said direction of said mobile radio terminal to which the the distance and azimuth angle are estimated by the estimating means the wireless LAN base station An antenna beam control device. Communication between the wireless LAN base station and the mobile wireless terminal from the time when the mobile wireless terminal enters the communication range of the wireless LAN base station after controlling the antenna beam by the antenna beam direction control means 5. The antenna beam control apparatus according to claim 4 , further comprising communication start means for starting the communication. A third notifying means for notifying the distance and azimuth from the wireless LAN base station estimated in the third estimation means to said mobile radio terminal to the mobile radio terminal, the distance in the third notifying means the mobile radio terminal away and the azimuth is notified, or claim 4, characterized by further comprising a beam steering means for directing the direction of the antenna beam of the mobile wireless terminal to the wireless LAN base station direction 5. The antenna beam control device according to 5 . A wireless LAN base station installed in a wireless LAN network by roaming, a mobile wireless base station installed in a cellular wireless network, and a mobile wireless terminal perform wireless communication, and the wireless LAN network A mobile communication system comprising a database device in which the installation position information of each of the wireless LAN base stations installed in the mobile station is stored in advance ,
The database device includes:
Based on the notified installation position information of the mobile radio base station, the installation position for acquiring the installation position information of the wireless LAN base station installed around the mobile radio base station and notifying the mobile radio base station Having information notification means,
The mobile radio base station is
First estimation means for estimating a distance and an azimuth from the mobile station to the mobile radio terminal when wirelessly communicating with the mobile radio terminal;
The wireless LAN base station notified from the own station by the installation position information notifying means using the installation position information of the own station and the installation position information of the wireless LAN base station notified by the installation position information notifying means Second estimation means for estimating the distance and azimuth to
Using the distance and azimuth angle from the local station estimated by the second estimation means to the wireless LAN base station and the distance and azimuth angle estimated from the first estimation means to the mobile radio terminal Te, said wireless from LAN base station estimates the distance and azimuth to the mobile radio terminal and a third estimation means for notifying the wireless LAN base station, the wireless LAN base station,
Based on the distance and azimuth angle notified from the mobile radio base station , control is performed so that the direction of the antenna beam of the local station is directed toward the mobile radio terminal where the distance and azimuth angle are estimated. A mobile communication system comprising antenna beam direction control means. The wireless LAN base station, after controlling the antenna beam by the antenna beam direction control means, between the mobile station and the mobile radio terminal from the time when the mobile radio terminal enters the communication range of the local station 8. The mobile communication system according to claim 7 , further comprising communication start means for starting communication. The mobile radio base station further includes distance and azimuth angle notifying means for notifying the mobile radio terminal of the distance and azimuth angle from the wireless LAN base station to the mobile radio terminal estimated by the third estimation means. And
The mobile radio terminal has beam direction control means for directing the direction of the antenna beam of the mobile terminal toward the direction of the wireless LAN base station based on the distance and the azimuth angle notified by the distance and notification means. The mobile communication system according to claim 8 or 9 .

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