JP2008283508A - Radio communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio communication system for suppressing frequency interference and frequency disturbance between channels to each other even in the case of providing different services to small adjacent areas in a plurality of small areas divided within a target area. <P>SOLUTION: The radio communication system 1 for allocating a plurality of channels divided in each frequency to each radio terminal device 40 to be used in a plurality of small areas divided within the target area 300 electromagnetically screened from the outside to perform communication services is provided with leakage coaxial cables 33a, 33b and 33c provided with an electromagnetic opening part at mutually different positions corresponding to each area; and a radio base station device 2 connected to the leakage coaxial cables 33a, 33b and 33c to allocate channels to small adjacent areas so as to prevent the channels from being continued to each other. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a wireless communication system, and in particular, a plurality of wireless terminal devices provided for each seat in a passenger cabin area of a mobile engine such as a train, a bus, and an aircraft, and a server that distributes video, audio, and information services The present invention relates to a wireless communication system for performing wireless communication.

  In recent years, wireless communication systems such as IEEE802.11a / b / g are becoming widespread. These are called wireless local area network (hereinafter referred to as “LAN”) systems, and have the same functions as Ethernet (registered trademark) used in wired LAN systems. ing.

  The wireless LAN system was originally used as a communication system for portable and portable personal computers, portable wireless terminal devices, etc., but the range of use has been evaluated due to the advantages of having no complicated wiring cables. The technology for applying to a terminal device in which the use position is fixed has been proposed.

  As an example, a technique has been proposed in which a wireless LAN system is installed in an aircraft and content such as video and audio is distributed to a wireless terminal device provided in a passenger seat (see, for example, Patent Document 1).

  In this example, a plurality of wireless access points (hereinafter referred to as “access points”) are installed as radio base station apparatuses. The installation position of each access point is determined so that one access point can cover a plurality of wireless terminal devices. Each access point is connected to a server that stores data for providing content to passengers. In addition, the service area in the aircraft is divided into a plurality of small areas and assigned so that one access point corresponds to one small area. As measures to prevent radio wave interference and interference between small areas, antennas with sharp directivity are placed at each access point, and a specific channel is used for each wireless terminal device in the small area. , Perform time-division communication. Accordingly, content such as VOD (VIDEO On Demand) can be distributed to a plurality of wireless terminal devices through one channel. However, in this method, the propagation path from the access point to the wireless terminal device is limited, and radio waves do not reach when there are obstacles such as shielded partition walls. Accordingly, it is necessary to install a large number of access points in order to reach the necessary quality of radio waves within the required range.

  On the other hand, a technique of using a leaky coaxial cable as an antenna for radio wave radiation is disclosed (for example, see Patent Document 2).

As another example of using a plurality of leaky coaxial cables, a technique for providing a service in a limited narrow area in a building has been proposed (see, for example, Patent Document 3).
JP 2006-33676 A JP-A-1-155730 JP 2005-101861 A

  However, the conventional method in which an access point and each wireless terminal device use one channel in a time-sharing manner has a narrow band per wireless terminal device. For example, even if the communication speed is 20 Mbps per channel, if the number of wireless terminal devices that can be supported by one access point is 20, the wireless terminal device is 1 Mbps per device, which is used for video and audio data distribution. There were quality issues to use. As a countermeasure against this, there is a method of installing a large number of access points, but there has been a problem of frequency interference and interference between adjacent channels. Even when a leaky coaxial cable with sharp directivity is used as an antenna so that radio waves can reach a narrow range, the radio wave ranges overlap in adjacent areas, so interference and interference between adjacent channels are a problem Met.

  The present invention has been made to solve the above-described problem, and even in a case where different services are provided for each small area in a plurality of small areas divided within the target area, between adjacent small areas. An object of the present invention is to provide a high-quality wireless communication system by suppressing frequency interference and frequency interference between channels.

  In order to achieve the above-described object, the wireless communication system of the present invention is used for a plurality of wireless terminal devices used in a plurality of small areas divided in a target area electromagnetically shielded from the outside. A wireless communication system that performs communication services by allocating a plurality of channels divided for each frequency, and a plurality of leaky coaxial cables having electromagnetic openings at different positions corresponding to a plurality of small areas, and The wireless base station apparatus is connected to a plurality of leaky coaxial cables, and has a radio base station apparatus that allocates a channel in which adjacent channels are not continuous to a plurality of leaky coaxial cables in adjacent small areas.

  According to such a configuration, channels that are not continuous with each other can be assigned to adjacent small areas. Therefore, even when different services are provided for each small area, frequency interference and frequency interference between channels can be suppressed in adjacent small areas, and a high-quality and high-functional radio communication system is provided. can do.

  In the wireless communication system of the present invention, the leaky coaxial cable may be provided with a radio wave leaking part that leaks radio waves in a part where the shield is removed as an electromagnetic opening.

  According to such a configuration, the radio wave can be leaked from the radio wave leakage portion provided in the portion where the shield of the leaky coaxial cable is removed, and even if the length of the leaky coaxial cable is long, Attenuation can be suppressed. Further, the frequency and radiation direction of the leaked radio wave can be set by processing and arranging the slot provided in the radio wave leaking part.

  Moreover, you may overlap a small area partially. According to this, it becomes possible to cover all areas of the service area where the communication service needs to be performed among the target areas by a plurality of small areas, eliminating gaps in which service cannot be provided in the service area, and high quality. A wireless communication system can be realized.

  In addition, the radio base station apparatus groups a plurality of channels so that the channels are not continuous in adjacent small areas, and assigns the grouped channel group to each of the plurality of leaky coaxial cables. Also good.

  According to this, even when a plurality of leaky coaxial cables are used for a plurality of small areas, a channel group in which the channels are not continuous is allocated to each of the leaky coaxial cables in adjacent small areas. be able to. Therefore, necessary channels can be effectively used from the channel group. For example, even when one channel cannot be used, it is possible to select another channel from the channel group so that the adjacent channels do not continue to each other.

  Further, when the number of wireless terminal devices that can provide a service on one channel is exceeded, another channel may be added from the channel group assigned to the leaky coaxial cable.

  This further increases the number of wireless terminal devices that can provide services while suppressing frequency interference and frequency interference between channels in adjacent small areas.

  Further, when a channel that cannot be used is generated, another channel may be assigned from the channel group assigned to the leaky coaxial cable.

  According to this, even when a channel that can no longer be used is generated, another channel can be assigned while suppressing frequency interference and frequency interference between adjacent channels in a small adjacent area. Can be provided continuously.

  Alternatively, the plurality of leaky coaxial cables may be installed in parallel to the longitudinal direction of the mobile engine.

  According to this, it is possible to provide a communication service using a plurality of leaky coaxial cables provided in parallel with the longitudinal direction of the mobile engine. For example, the directivity characteristics of a leaky coaxial cable can be effectively used in a communication service in a railway vehicle or an aircraft.

  Further, the opening of the leaky coaxial cable may have a plurality of slots, and the plurality of slots may be arranged symmetrically on both sides of the opening.

  According to such a configuration, even if the target area is a small area divided in the longitudinal direction, radio waves can be efficiently radiated in a direction orthogonal to the longitudinal direction of the mobile engine, and adjacent small areas Since the radiation directions of radio waves do not overlap each other, radio wave interference can be effectively suppressed. Further, it can be disposed at a location close to each wireless terminal device on both sides of the leaky coaxial cable, for example, in the center with respect to the width direction of the mobile engine, and a communication service can be provided in a stable radio wave state.

  Further, the plurality of slots may be provided corresponding to the position of the seat installed in the mobile engine.

  According to this, it is possible to radiate radio waves toward the seat where the wireless terminal device is used, and to efficiently supply radio waves.

  The mobile engine may be a railway vehicle or an aircraft. According to this, the communication service can be used in a moving railway vehicle or in an aircraft, and even if a frequency that cannot be used due to the laws of the country or region in the place of movement occurs. Can be used continuously.

  According to the present invention, even in a case where different services are provided for each small area in a plurality of small areas divided within the target area, frequency interference or frequency interference between channels between adjacent small areas. It is possible to provide a wireless communication system that suppresses the above.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
First, the configuration of the wireless communication system according to Embodiment 1 of the present invention will be described using FIG. FIG. 1 is a block diagram showing a configuration of a wireless communication system 1 in the present embodiment.

  As shown in FIG. 1, the wireless communication system 1 includes small areas A1, A2, A3,... Divided in an electromagnetically shielded area 300 (hereinafter referred to as “target area”). A communication service is performed by allocating a plurality of channels divided by frequency to each wireless terminal device 40 used in An, and corresponds to small areas A1, A2, A3,. Are connected to leaky coaxial cables 33a, 33b, 33c and leaky coaxial cables 33a, 33b, 33c provided with electromagnetic wave leaking portions 20A1, 20A2, 20A3,..., 20An as electromagnetic openings at different positions. The adjacent small area includes a radio base station apparatus 2 that assigns channels that are not continuous to each other to leaky coaxial cables 33a, 33b, and 33c. That.

  As a result, since the channels are not continuous in adjacent small areas, different services are provided for each small area in the small areas A1, A2, A3,. Even in this case, interference between channels and frequency interference can be suppressed in adjacent small areas, and a high-quality and highly functional wireless communication system can be provided.

  The target area 300 electromagnetically shielded from the outside includes, for example, the inside of a mobile engine (railway vehicle, aircraft, bus, etc.) and the inside of a shielded space in a building (office, etc.). This embodiment will be described as an area inside the mobile engine. Each of the small areas A1, A2,..., An includes a place where the wireless terminal device 40 is used or a place where the wireless terminal device 40 is installed, for example, a seat installed in a mobile organization. Separated by position and range.

  Next, a detailed configuration of radio communication system 1 in the present embodiment will be described using FIG. 2 and FIG. FIG. 2 is a block diagram showing the configuration of the radio base station apparatus 2 in the radio communication system 1 of the present embodiment, and FIG. 3 is a structural diagram showing the structure of the leaky coaxial cable in the radio communication system 1.

  First, as shown in FIG. 2, the radio base station apparatus 2 is connected to an external server 10 via an Ethernet (registered trademark) or the like and transmits / receives necessary data to / from the server 10. The server 10 stores data related to the content that is the target of the communication service. For example, the contents include movies, news, shopping information, tourist information, weather information, music, map information, and usable device operation information. In addition, the server 10 is connected to a network outside the mobile institution, and can acquire various data information (content other than the accumulated content).

  The radio base station apparatus 2 includes a switching unit 31, modulation / demodulation units 32a, 32b, and 32c, and a channel management unit 36.

  The switching unit 31 distributes the content acquired from the server 10 to each channel (communication path). The switching unit 31 outputs data to the modulation / demodulation units 32a, 32b, and 32c in order to distribute content to the requested small areas A1, A2,. When the switching unit 31 acquires demodulated data information output from the modems 32 a, 32 b, and 32 c, the switching unit 31 transmits the data information to the server 10.

  The modem unit 32a modulates the received data to a radio frequency for each assigned channel and outputs the modulated data to the leaky coaxial cable 33a. Similarly, the modem unit 32b modulates data and outputs it to the leaky coaxial cable 33b, and the modem unit 32c modulates data and outputs it to the leaky coaxial cable 33c.

  Further, the modem unit 32 a demodulates the radio wave received by the leaky coaxial cable 33 a for each channel, and outputs the demodulated data information to the switching unit 31. Similarly, the modem unit 32b demodulates the radio wave received by the leaky coaxial cable 33b for each channel, and the modem unit 32c demodulates the radio wave received by the leaky coaxial cable 33c for each channel and outputs it to the switching unit 31. To do.

  As the modems 32a, 32b, and 32c, for example, data is distributed / parallel / multiplexed and transmitted by a known digital modulation scheme, for example, an orthogonal frequency division multiplexing scheme. On the contrary, when performing demodulation, the reverse process is performed.

  In addition, various access methods can be used for each wireless terminal device 40 and the server 10 to communicate bidirectionally with each other via the wireless base station device 2. For example, there are frequency division multiple access, time division multiple access, and code division multiple access, and any one method is selected, and access control is performed according to the selected connection method.

  The channel management unit 36 groups a plurality of channels whose channels are not continuous in adjacent small areas, and assigns the grouped channel group to each leaky coaxial cable 33a, 33b, 33c.

  When the number of wireless terminal devices 40 that can be handled by one channel is exceeded, the channel management unit 36 adds another channel from the channel group assigned to one leaky coaxial cable. Thus, for example, if one channel has a bandwidth of 20 Mbps and one communication service can be provided in the 1 Mbps bandwidth, different communication services are provided to 20 wireless terminal devices 40. However, different communication services cannot be provided to the 60 wireless terminal devices 40. In this case, it is possible to provide different communication services to 60 wireless terminal apparatuses 40 by adding another two channels from the channel group assigned to one leaky coaxial cable.

  In addition, when an unusable channel occurs, the channel management unit 36 selects and uses another channel from the assigned channel group.

  In addition, even in the same 5 GHz band, it was also assigned when a frequency (a frequency that cannot be used due to legal regulations) that cannot be used in places where radio waves are used (regions, countries, etc.) Select another channel from the channel group and respond. Thereby, especially when the radio base station apparatus 2 is installed in a mobile engine and the mobile engine moves from place to place, an effect can be exhibited.

  Further, when performing a broadcast communication service such as an emergency guide, the communication service can be performed for 60 wireless terminal devices 40 in a small area with one channel.

  Next, the structure of the leaky coaxial cables 33a, 33b, and 33c will be described with reference to FIG. Since each leaky coaxial cable 33a, 33b, 33c has the same configuration, only the leaky coaxial cable 33a will be described here.

  In the leaky coaxial cable 33a, a central conductor (not shown) for distributing data is covered with an insulator (not shown), and the insulator is covered with an external conductor 24. The outer conductor 24 is shielded by a shield 25, and the shield 25 is further covered with a protective outer covering 26. This prevents radio waves transmitted through the central conductor from leaking. The leaky coaxial cables 33b and 33c have the same configuration.

  The covering portion 23 is cut open as a portion from which the shield 25 is removed as an electromagnetic opening, that is, a radio wave leakage portion 20A1, in some places. For example, a plurality of slots 21 are provided in the radio wave leakage unit 20A1. The slot 21 functions as a transmission / reception antenna and strongly radiates radio waves in the direction of the slot 21. The shape and arrangement of the slot 21 are designed according to the frequency to be used and the radiation direction of the radio wave. Details of the arrangement of the slots 21 will be described later.

  Further, termination resistors 50a, 50b, and 50c for suppressing reflected waves are provided at the termination portions of the leaky coaxial cables 33a, 33b, and 33c, respectively.

  By using the leaky coaxial cables 33a, 33b, and 33c, even if there is an obstacle 200 (for example, a partition wall that shields radio waves) in the target area 300, the leaky coaxial cable 33a is avoided by avoiding the obstacle 200. , 33b, 33c can provide communication services to all of the small areas A1, A2,..., An.

  As described above, in the wireless communication system 1 according to the present embodiment, by assigning channels that are not continuous to each other to adjacent small areas, the small areas A1, A2, ... Even if different communication services are provided to each wireless terminal device 40 used in An, it is possible to suppress frequency interference and frequency interference between channels in adjacent small areas. . Thereby, it is possible to provide a wireless communication system 1 with high quality and high functionality.

  Next, a specific example when the wireless communication system 1 is installed inside the mobile engine 100 will be described with reference to FIG. FIG. 4 is a layout diagram showing a relationship with a service area when the wireless communication system 1 of the present embodiment is installed inside a mobile engine.

  The wireless communication system 1 is installed in, for example, an elongated mobile engine 100 (railway vehicle, bus, aircraft, etc.). Such a mobile engine 100 is electromagnetically shielded by a vehicle body that separates the inside and outside of the mobile engine 100, and further, a work area such as a door between the vehicles, a partition wall, and a kitchen for the cabin crew to prepare for service. One or more obstacles 200 such as (hereinafter, this work area is referred to as “galley”) are provided. The inside of the mobile institution 100, for example, a guest room is a target area 300, and a communication service is provided to each wireless terminal device 40 used in the small areas A1, A2,. . In the present embodiment, the target area 300 in the mobile engine 100 is divided into three areas by the obstacle 200, and a place (for example, a seat) where a wireless terminal device (not shown) is used in each area. ) Are grouped into three small areas A1 to A3, A4 to A6, and A7 to A9. Adjacent small areas have partially overlapping regions (for example, C1, C2, etc. in the small areas A1 to A3 groups).

  Further, in the wireless communication system 1, leaky coaxial cables 33a, 33b, and 33c are arranged corresponding to the three small areas that are grouped. Leaky coaxial cables 33 a, 33 b, and 33 c are respectively disposed in parallel with the longitudinal direction D of the mobile engine 100.

  Moreover, one end of each of the leaky coaxial cables 33a, 33b, and 33c is connected to the modulation / demodulation units 32a, 32b, and 32c of the radio base station device 2, and the terminating resistors 50a, 50b, and 50c are connected to the other ends, respectively. Provided.

  Among these, in the leaky coaxial cable 33a, the radio wave leaking part 20A1 corresponding to the grouped small area A1, the radio wave leaking part 20A4 corresponding to the small area A4, and the radio wave leak corresponding to the small area A7. Each part 20A7 is provided. Similarly, in the leaky coaxial cable 33b, the radio wave leakage portions 20A2, 20A5, 20A8 for the small areas A2, A5, A8, and in the leaky coaxial cable 33c, the radio wave leakage portions 20A3, 20A6, for the small areas A3, A6, A9, 20A9 is provided.

  Thus, the leaky coaxial cable 33a can radiate radio waves from the radio wave leaking portions 20A1, 20A4, and 20A7 in the small areas A1, A4, and A7, respectively. Accordingly, a communication service including various types of content transmitted from the radio base station apparatus 2 to each radio terminal apparatus 40 (not shown) used in the small areas A1, A4, and A7 by the leaky coaxial cable 33a. Can be provided. Similarly, communication services can be provided to each wireless terminal device 40 (not shown) used in the small areas A2, A5, A8, A3, A6, and A9 by the leaky coaxial cables 33b and 33c. .

  As a result, communication service information transmitted from the radio base station apparatus 2 is provided to all radio terminal apparatuses 40 used in the small areas A1, A2,... can do.

  Next, a method for suppressing frequency interference in the above-described region where adjacent small areas partially overlap (for example, C1 and C2 illustrated in FIG. 4) will be described with reference to FIG. FIG. 5 is a diagram illustrating an example of channel arrangement in a frequency band of 5 GHz used in the wireless communication system 1 according to the present embodiment.

  In the wireless communication system 1, when performing communication service by allocating a plurality of channels divided by frequency, in order to suppress frequency interference in adjacent small areas, the channels are continuous in adjacent small areas. A channel that should not be assigned is assigned.

  Accordingly, as shown in FIG. 5, when a plurality of channels are allocated and used, there is almost no region where the transmission frequencies overlap between the channels indicated by the solid lines and between the channels indicated by the broken lines. The quality of communication service can be ensured without interference.

  On the other hand, the area where the transmission frequencies overlap is larger between two adjacent channels indicated by a broken line than one channel indicated by a solid line. Thus, when the region where the transmission frequencies overlap between channels is large, frequency interference is likely to occur, and the quality of the communication service is deteriorated. The same applies to two adjacent channels indicated by a solid line with respect to one channel indicated by a broken line. In a high frequency band used for a wireless LAN, if continuous channels are used in a region where the frequencies intersect, the frequencies interfere with each other and the quality of communication service deteriorates.

  Thus, frequency interference can be suppressed by assigning channels that are not continuous to each other to adjacent small areas.

  Next, the operation of the wireless communication system 1 will be described with reference to FIG. First, in the wireless communication system 1, a usable channel is assigned to leaky coaxial cables 33 a, 33 b, and 33 c among a plurality of channels divided for each frequency. That is, the wireless communication system 1 uses the wireless base station device 2 to group channels that can be used into a plurality of channels. At this time, the radio base station apparatus 2 performs grouping based on a table (hereinafter, this table is referred to as “channel management table 30”) in which channel information allocated so that the channels are not continuous between the groups is recorded. Turn into. Here, “a channel that can be used” is not limited to a channel that is used by another device outside the mobile institution 100 or a channel that can be physically used, but also a national or regional law. It also means that the channel is not regulated by. Details of channel assignment will be described later.

  Next, the wireless communication system 1 assigns the grouped channels to the leaky coaxial cables 33a, 33b, and 33c. Thereby, the radio | wireless communications system 1 can allocate a channel so that a mutual channel may not become continuous with respect to an adjacent small area.

  Next, in the wireless communication system 1, the channel management unit 36 records the grouped channel group information and the information assigned to the leaky coaxial cables 33 a, 33 b, 33 c in the channel management table 30. The channel management table 30 is stored in a memory (not shown). Details of the channel assignment will be described later.

  Next, the wireless communication system 1 selects a channel for providing a communication service from the channel group assigned to the leaky coaxial cables 33a, 33b, 33c according to the channel management table 30 stored in the memory. use.

  When a channel that cannot be used occurs, the wireless communication system 1 selects and uses another channel from the assigned channel group, and can use it in a place (region, country, etc.) where radio waves are used. When a frequency that cannot be generated is generated, another channel is selected from the assigned channel group.

  Note that the channel management unit 36 may update the channel management table 30 when a frequency that cannot be used at the location where the mobile organization 100 has moved is generated. Also, the channel management table 30 may include information on spare channels used for emergency guidance. This further suppresses frequency interference even in an emergency.

  Next, channel assignment in the wireless communication system 1 will be described in detail with reference to FIGS. FIG. 6 is a group configuration diagram illustrating an example in which the channel management unit 36 in the wireless communication system 1 according to the present embodiment assigns a plurality of channels to three groups. FIG. 7 illustrates the channel management unit 36 in the wireless communication system 1. FIG. 8 is a group configuration diagram illustrating an example in which the channel management unit 36 in the wireless communication system 1 allocates a plurality of channels to 5 groups. is there.

  First, a case where a plurality of channels are allocated to three groups will be described with reference to FIG. Here, a case where the number of channels that can be used in the range in which the mobile engine 100 moves is “19” or “23” will be described.

  First, when using the same frequency band of 5 GHz, for example, the number of channels that can be used in 36CH to 52CH is “4”, channels that can be used in 56CH to 64CH and 100CH to 140CH. When the number is “15” and the number of channels that can be used in 149CH to 161CH is “4”, the total number of channels that can be used is “23”. Therefore, the channel management unit 36 selects a channel from the number of available channels “23” and performs grouping. The grouped channel group information is stored as a channel management table 30 in a memory (not shown) in the channel management unit 36.

  As shown in FIG. 6, when the channel management unit 36 assigns groups 1, 2 and 3 as channel groups for providing communication services to the small areas A1 to A3 (FIG. 4), for example, When the number of channels that can be used is “19”, the channel assigned to group 1 is assigned to the 36th channel (hereinafter referred to as this channel) for group 1 and group 2 used in adjacent small area A1 and small area A2. The 36th channel is referred to as “36CH”, the same applies hereinafter), 60CH, 116CH, and 140CH, and the channels assigned to group 2 are 44CH, 100CH, and 124CH. As a result, group 1 and group 2 do not include continuous channels. That is, the channel management unit 36 assigns the group 1 channel group to the leaky coaxial cable 33a and assigns the group 2 channel group to the leaky coaxial cable 33b, so that the small area A2 and the small area A3 are not continuous with each other. A channel is allocated. Similarly, channels assigned to groups 2 and 3 (groups assigned to the leaky coaxial cable 33c) used in the small areas A2 and A3 adjacent to each other are also assigned channels that are not continuous with each other in the adjacent small areas. Yes.

  Next, similarly, the channel management unit 36 also continuously assigns channels assigned to the groups 1 and 2 used in the small area A1 and the small area A2 adjacent to each other even when the number of assignable channels is “23”. Similarly, channels that are not continuous are set for the groups 2 and 3 that are used in the small area A2 and the small area A3 that are adjacent to each other.

  Similarly, FIG. 7 shows a case where the channel manager 36 assigns a plurality of channels to four groups, and FIG. 8 shows a case where the channel manager 36 assigns a plurality of channels to five groups. Yes. The grouped channel groups are assigned to small areas adjacent to each other in order.

  By increasing the number of groups in this way, the channel management unit 36 can allocate channels efficiently. As the channel, a channel that can be used is selected from the same frequency band, for example, a band of 5 GHz or 2.4 GHz.

  In addition, although the case where channels are selected from the same frequency band and grouped has been described, channels of different frequency bands may be used for devices that provide communication services. A description of the case of using channels of different frequency bands will be given later.

  As described above, according to radio communication system 1 in Embodiment 1 of the present invention, channels that are not continuous with each other can be allocated to adjacent small areas. Therefore, even when different services are provided for each of the small areas A1, A2,..., A9, it is possible to suppress frequency interference and frequency interference between channels in adjacent small areas, and high quality. Thus, a highly functional wireless communication system can be provided.

  Further, the radio base station apparatus 2 groups a plurality of channels so that the channels are not continuous in adjacent small areas, and assigns the grouped channel groups to the leaky coaxial cables 33a, 33b, and 33c, respectively. This makes it possible to effectively use the necessary channels from the channel group. For example, when the number of wireless terminal devices 40 that can be handled by one channel is exceeded, another channel can be added from the channel group assigned to the leaky coaxial cable. Thereby, the number of the radio | wireless terminal apparatuses 40 corresponding to a service can be increased, suppressing the frequency interference and frequency interference between channels in an adjacent small area.

  In addition, when a communication service can be used within a moving mobile organization (for example, in a railcar or an aircraft), and a frequency that cannot be used due to the laws of the country or region in which the mobile facility has moved is generated. Even so, it is possible to assign another channel from the channel group assigned to each of the leaky coaxial cables 33a, 33b, and 33c. As a result, even if a channel that cannot be used due to legal regulations occurs, communication services continue using another channel while suppressing frequency interference and frequency interference between channels in adjacent small areas. Can be provided.

  Note that the number of leaky coaxial cables is not limited to three. You may arrange | position the required number of leaky coaxial cables. For example, the number of leaky coaxial cables may be set according to the number of small areas to be divided and the number of wireless terminal devices 40 that provide wireless services.

(Embodiment 2)
Next, radio base station apparatus 3 in radio communication system 1 according to Embodiment 2 of the present invention will be described using FIG. 9 and FIG. FIG. 9 is a block diagram showing a configuration of the radio base station apparatus 3 in the radio communication system 1 of the present embodiment, and FIG. 10 shows frequency bands used in the radio base station apparatus 3 of the radio communication system 1 of the present embodiment. It is a figure which shows the channel allocation example with respect to radio | wireless apparatus 34a, 34b, 34c. Hereinafter, in FIG. 9, the same reference numerals are given to the same components as those of the wireless communication system 1 according to the first embodiment.

  The radio base station apparatus 2 in the first embodiment uses the same frequency band channel. On the other hand, radio base station apparatus 3 according to Embodiment 2 of the present invention is different in that channels in different frequency bands are used. The radio base station apparatus 3 provides a communication service in the mobile organization 100 using both the 5 GHz and 2.4 GHz frequency bands used for the wireless LAN.

  As shown in FIG. 9, the radio base station apparatus 3 includes a switching unit 31, modulation / demodulation units 35a, 35b, and 35c that modulate and demodulate data, and a channel management unit 36 that manages channels. The radio base station apparatus 3 is connected to the server 10.

  The switching unit 31 distributes and collects data when the server 10 and the wireless terminal device 40 transmit and receive data information via the modems 35a, 35b, and 35c.

  Since the modems 35a, 35b, and 35c all have the same configuration, only the modem 35a will be described here.

  The modem unit 35 a includes wireless devices 34 a, 34 b, 34 c and a multiplexing / separating unit 37.

  The multiplexing / demultiplexing unit 37 is capable of bidirectional transmission / reception, multiplexes the outputs from the wireless devices 34a, 34b, and 34c, and outputs them to the leaky coaxial cable 33a. Further, the multiplexing / separating unit 37 separates the radio wave received by the leaky coaxial cable 33a with a splitter or the like, and outputs it at the frequency of each of the wireless devices 34a, 34b, 34c.

  The wireless device 34a modulates and demodulates data according to the channel assigned by the channel manager 36. Similarly, the radio apparatuses 34b and 34c also perform data modulation and demodulation according to the channel assigned by the channel management unit 36. Here, channel assignment to each of the wireless devices 34a, 34b, and 34c will be described later.

  The modulation / demodulation unit 35a is connected to the leaky coaxial cable 33a and radiates radio waves from the radio wave leakage units 20A1, 20A4, 20A7 provided corresponding to the small areas A1, A4, A7, and is used in the small areas A1, A4, A7. Wireless communication service information is provided to a wireless terminal device 40 (not shown).

  Similarly, the modem unit 35b is connected to the leaky coaxial cable 33b and radiates radio waves from the radio wave leaking units 20A2, 20A5, and 20A8 provided corresponding to the small areas A2, A5, and A8, and the modem unit 35c is a leaky coaxial cable. Radio terminal device 40 (not shown) used in each small area by radiating radio waves from radio wave leakage sections 20A3, 20A6, 20A9 connected to 33c and provided corresponding to small areas A3, A6, A9. Provides wireless communication service information.

  Next, the operation of radio base station apparatus 3 in the present embodiment will be described. As shown in FIG. 10, the radio base station apparatus 3 uses a channel of a frequency band of 5 GHz for the radio apparatuses 34a and 34b, and allocates, for example, 36CH and 44CH, respectively. Also, the radio base station apparatus 3 uses a channel in the 2.4 GHz frequency band and allocates 11CH to the radio apparatus 34c. Note that frequency allocation and channel allocation are not limited to this embodiment. Further, frequency allocation and channel allocation may be performed in advance before or after the wireless communication system 1 is installed.

  Thereby, the radio base station apparatus 3 can stably provide a communication service using radio waves of different frequency bands for each small area. For example, since a 2.4 GHz band wireless terminal device is standardly installed in Bluetooth, personal computers, game machines, and the like, these devices may cause frequency interference and may affect the wireless base station device 3. Is expensive. Therefore, a 2.4 GHz frequency band is used for data services such as personal computers, and a 5 GHz frequency band is used for streaming distribution of music (Audio) and movies (Video). Interference can be suppressed and communication services can be provided stably.

  In addition, since the slot 21 provided in the radio wave leakage portions 20A1, 20A2, and 20A3 is 5 GHz and 2.4 GHz and the slot shape and size thereof are different, for example, the radio wave leakage portions 20A1, 20A2, and 20A3 have 5 GHz and 2 A slot having a dedicated shape and size may be provided for each of 4 GHz.

  As described above, according to the radio base station apparatus 3 in the radio communication system 1 according to the second embodiment of the present invention, by providing a communication service to each radio terminal apparatus 40 using radio waves in different frequency bands, Communication services can be stably provided by suppressing frequency interference between the communication system 1 and wireless devices such as general Bluetooth, personal computers, and game devices.

(Embodiment 3)
Next, the radio | wireless communications system 1 in Embodiment 3 of this invention is demonstrated using FIGS. Here, an example in which the wireless communication system 1 is arranged in the mobile engine 100 will be described.

  11 is a side view showing an example of the arrangement of leaky coaxial cables in the radio communication system 1 of the present embodiment, FIG. 12 is a plan view showing an example of arrangement of leaky coaxial cables in the radio communication system 1, and FIG. It is a figure which shows the relationship between the radiation characteristic of the electromagnetic wave radiated | emitted from the leaky coaxial cable in the system 1, and a small area. Hereinafter, the same components as those in the wireless communication system 1 according to Embodiment 1 will be described with the same reference numerals.

  As shown in FIG. 11, the radio base station apparatus 2 and the leaky coaxial cables 33a, 33b, 33c are arranged on the ceiling of the mobile engine 100 and correspond to the radio terminal apparatus 40 installed in the seats in each small area. Each radio wave leaking part 20A1, 20A2, 20A3 is provided nearby. Thereby, a radio wave state can be stabilized.

  Also, as shown in FIG. 12, in the wireless communication system 1 according to the present embodiment, a plurality of chairs (seats) used by the user are included in the small area A1 divided within the target area 300 in the mobile engine 100. Are grouped and set as seat groups SG1, SG2,..., SG6. Here, for example, each wireless terminal device 40 is installed behind each chair.

  Leaky coaxial cables 33a, 33b, and 33c are arranged in parallel to the longitudinal direction D (Y-axis direction) of the mobile engine 100, respectively, and enhance the directivity of radio waves in the direction orthogonal to the cable (X-axis direction). Making it easy.

  Further, the radio wave leaking portion 20A1 is provided at a position corresponding to the small area A1 of the leaky coaxial cable 33a. Further, as shown in FIG. 12, the radio wave leaking portion 20A1 has slots 21A11, 21A12 corresponding to the spacing of the seats. 21A16 are symmetrically arranged on both sides of the leaky coaxial cable 33a. By directing the direction of the slots 21A11, 21A12,..., 21A16 toward the seat groups SG1, SG2,..., SG6, radio waves are radiated strongly in that direction. For the small areas A2 and A3, the radio wave leakage portions 20A2 and 20A3 are arranged in the same configuration.

  Specifically, as shown in FIG. 13, in the slots 21A11, 21A12,..., 21A16, the radio waves are strengthened in the arrangement direction of the seat groups SG1, SG2,. In addition, directional characteristics SD1, SD2,..., SD6 are provided so that the radiation direction does not overlap with other seat groups. As a result, the wireless communication system 1 according to the present embodiment can provide a stable radio wave with reduced frequency interference to the wireless terminal device 40 used in each seat group. Communication services can be provided efficiently. Here, each wireless terminal device 40 is fixedly arranged in each seat.

  Further, the slots 21A11, 21A12,..., 21A16 are provided symmetrically on both sides of the leaky coaxial cable 33a as shown in FIG. It can arrange | position in the vicinity and the distance of each radio | wireless terminal apparatus 40 on both sides of the leaky coaxial cable 33a and the leaky coaxial cable 33a can be shortened. Thereby, an efficient and stable radio wave can be provided to both sides of the leaky coaxial cable 33a.

  Although the leaky coaxial cables 33a, 33b, and 33c are arranged on the ceiling, the present invention is not limited to this. For example, the same effect can be obtained even if the leaky coaxial cables 33a, 33b, 33c are arranged on the floor.

  As described above, according to the wireless communication system 1 according to the third embodiment of the present invention, the leaky coaxial cables 33a, 33b, 33c are arranged parallel to the longitudinal direction D of the mobile engine 100 and orthogonal to the cables. By strengthening the directional characteristics of the radio waves in the direction of the seat groups SG1, SG2,..., SG6, the radio waves become stronger in the arrangement direction of the seat groups SG1, SG2,. Directional characteristics SD1, SD2,..., SD6 that do not overlap with the group are obtained. This solves a problem that occurs when dividing and dividing in parallel with the longitudinal direction (such as a problem that the directivity directions of radio waves radiated from the slots overlap and radio wave interference increases), and the slots 21A11, 21A12, ..., interference of radio waves radiated from 21A16 can be suppressed.

  In addition, although the case where the radio | wireless terminal apparatus 40 was fixed to the seat was demonstrated, it is not limited to this. The wireless terminal device 40 may be detachably installed on the seat. Further, another wireless terminal device brought from outside the mobile engine 100 may be used in the seat. The same effect can be exhibited also by this.

  Moreover, in the radio | wireless communications system 1 of Embodiment 1-3, although the case where the service was provided by multiplexing a plurality of channels on one leaky coaxial cable was described, another leaky coaxial cable is further added. Also good. For example, when transmitting video / audio stream data such as a movie using two leaky coaxial cables, when transmitting packet A, packet B, packet C, and packet D, which are continuous data, Packet A and packet C are transmitted to the leaky coaxial cable, and packet B and packet D are transmitted to the other leaky coaxial cable. That is, packet A, packet B, and packet C packet D are transmitted simultaneously. As described above, by simultaneously transmitting a plurality of data (streams), it becomes possible to transmit, for example, even high-bit-rate image / audio data, and a high-quality service can be provided. The number of leaky coaxial cables is not limited to two, and the number (plurality) necessary for transmitting high bit rate image / audio data may be set.

  Further, the case where the wireless communication system 1 is installed in the mobile engine 100 has been described, but this is a case where a communication service is provided to a plurality of small areas divided inside a space (eg, an office) shielded in a building. However, the same effect can be exhibited.

  The specific configuration of the present invention is not limited to the above-described first to third embodiments, and various changes and modifications can be made without departing from the scope of the invention.

  According to the present invention, it is possible to suppress frequency interference and frequency interference between channels even when providing different services to adjacent small areas in a plurality of small areas divided within the target area. Therefore, it is useful as a radio communication system, a radio base station apparatus, a radio communication method, and the like.

1 is a block diagram showing a configuration of a wireless communication system according to Embodiment 1 of the present invention. A block diagram showing a configuration of a radio base station apparatus in the radio communication system Structural diagram showing the structure of a leaky coaxial cable in the same wireless communication system Arrangement diagram showing the relationship with the service area when the wireless communication system is installed inside the mobile engine The figure which shows the example of arrangement | positioning of the channel in the frequency band of 5 GHz utilized with the radio | wireless communications system Group configuration diagram showing an example of channel assignment by the channel manager in the same wireless communication system Group configuration diagram showing another example of channel assignment of channel manager in the same wireless communication system Group configuration diagram showing another example of channel assignment of channel manager in the same wireless communication system FIG. 3 is a block diagram showing a configuration of a radio base station apparatus in the radio communication system according to the second embodiment of the present invention. The figure which shows the example of the channel allocation with respect to the frequency band and radio | wireless apparatus which are used in the radio | wireless base station apparatus of the radio | wireless communications system Side view showing an arrangement example of a leaky coaxial cable in the wireless communication system according to the third embodiment of the present invention. Top view showing an example of arrangement of leaky coaxial cable in the wireless communication system The figure which shows the relationship between the radiation characteristic of the electromagnetic wave radiated | emitted from the leaky coaxial cable in the same radio | wireless communications system, and a small area

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Radio | wireless communications system 2, 3 Wireless base station apparatus 10 Server 20A1, 20A2, ..., 20An Electric wave leaking part 20A11, 20A12, ..., 20A16, 21 Slot 23 Covering part 24 Outer conductor 25 Shielding body 26 Outer covering 30 Channel management table 31 Switching unit 32a, 32b, 32c, 35a, 35b, 35c Modulating / demodulating unit 33a, 33b, 33c Leaky coaxial cable 34a, 34b, 34c Wireless device 36 Channel management unit 37 Multiplexing / demultiplexing unit 40 Wireless terminal device 50a, 50b, 50c Termination resistance 100 Mobile engine 200 Obstacle 300 Target area A1, A2, ..., An Small area SG1, SG2, ..., SG6 Seat group SD1, SD2, ..., SD6 Directional characteristics

Claims (10)

Wireless that provides communication services by allocating multiple channels divided by frequency to multiple wireless terminal devices used in multiple small areas that have been electromagnetically shielded from the outside A communication system,
A plurality of leaky coaxial cables provided with electromagnetic openings at different positions corresponding to the plurality of small areas;
A radio base station apparatus that is connected to the plurality of leaky coaxial cables and assigns a channel that is not continuous to each other in the adjacent small areas to the plurality of leaky coaxial cables;
A wireless communication system comprising: The radio communication system according to claim 1, wherein the leaky coaxial cable is provided with a radio wave leaking part that leaks radio waves at a part where a shield is removed as the electromagnetic opening. The wireless communication system according to claim 1, wherein the small areas are partially overlapped. The wireless base station device
The plurality of channels are grouped so that the channels are not continuous in the adjacent small area, and the grouped channel group is assigned to each of the plurality of leaky coaxial cables. The wireless communication system according to any one of claims 1 to 3. When the number of the wireless terminal devices capable of providing a service by one channel is exceeded, another channel is added from the channel group assigned to the leaky coaxial cable. The wireless communication system according to claim 4. 5. The wireless communication system according to claim 4, wherein when a channel that cannot be used is generated, another channel is selected from the channel group assigned to the leaky coaxial cable. The radio according to any one of claims 1 to 6, wherein the wireless coaxial cable is installed inside an elongated mobile engine, and the plurality of leaky coaxial cables are arranged in parallel to a longitudinal direction of the mobile engine. Communications system. 8. The wireless communication system according to claim 7, wherein the opening portion of the leaky coaxial cable has a plurality of slots, and the plurality of slots are arranged symmetrically on both sides of the opening portion. The wireless communication system according to claim 8, wherein the plurality of slots are provided corresponding to positions of seats installed in the mobile engine. The wireless communication system according to any one of claims 7 to 9, wherein the mobile engine is a railway vehicle or an aircraft.

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