JP2008228023A - Radio communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio communication system in which interference or disturbance between channels are suppressed and specific contents such as an internal announcement can be quickly transmitted. <P>SOLUTION: A radio communication system comprises a first radio base station device (access point device 30) which assigns one channel to a target area and offers communication services to radio terminal devices 40 included within the target area and a second radio base station device (access point device 20), for each small area, which divides the target area into a plurality of different small areas, assigns channels, other than the channel assigned to the first radio base station device (access point device 30) for each of small areas and offers communication services to the radio terminal devices 40 included in the small areas, wherein the channel assigned to the first radio base station device (access point device 30) is a channel positioned at the end of a plurality of channels partitioned in the order of frequencies. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a wireless communication system for the passenger cabin area of a transportation facility such as an aircraft, and more particularly to a plurality of wireless terminal devices arranged in a passenger seat and a server for distributing video, audio and information services. The present invention relates to a wireless communication system for performing wireless communication with a connected wireless base station device.

  In recent years, wireless communication systems such as IEEE802.11a / b / g are becoming widespread. These are referred to as a wireless local area network system or a wireless LAN system for short, and are communication systems in which the equivalent of Ethernet (registered trademark) used in a wired LAN system is replaced by radio.

  The wireless LAN system was originally assumed to be used in portable and portable personal computers, portable wireless terminal devices, and the like. Thereafter, use in various fields has been widened, and for example, a technique for applying a wireless LAN system to a terminal device whose use position is fixed has been proposed for the purpose of eliminating the complexity of wiring cables and the like.

  As one of such technologies, a technology that uses a wireless LAN system for content distribution services such as video and audio in an aircraft has been proposed (for example, see Patent Document 1). That is, in a plane, a wireless LAN system is arranged as a wireless communication system, and content data is transmitted to a wireless terminal device installed in each passenger seat, thereby providing a content distribution system using the wireless LAN system. As well as forming, complicated wiring cables and the like are reduced.

  As a configuration of such a content distribution system, first, content data corresponding to content to be provided to passengers is stored in a server of the system. Further, a plurality of wireless access points (hereinafter referred to as access points) that are wireless base station devices connected to the server are installed in the aircraft. In addition, a wireless terminal device is installed for each seat, and the position of each access point is set so that one access point covers a plurality of wireless terminal devices.

  At this time, first, the in-flight space is divided into a plurality of small areas, and each access point is assigned to the in-flight so that one access point corresponds to one small area. In addition, the directional antenna of the access point is arranged so as to emit radio waves to other small areas as much as possible without causing interference and interference, and wirelessly using a fixed channel with each wireless terminal device in its own area. Set to communicate. In addition, by configuring one access point and each wireless terminal device in the small area to communicate by dividing the frequency band of the channel in time, a plurality of wireless terminal devices can be used in one channel. Individual content distribution services can be implemented.

  In addition, as channel allocation to each access point, for example, allocation is performed as follows. That is, when there are 8 channels available, for example, the first small area of the in-flight space is assigned to the first channel, and the next small area is assigned to the second channel in order. Further, the ninth small area is returned to the first channel, the first channel is assigned, and the tenth small area is assigned in order, such as the second channel. By performing such channel assignment, it is possible to reuse a finite number of channels in the in-flight space, and to suppress interference and interference between channels.

  By configuring such a wireless LAN system in an aircraft, content data such as video and audio can be sent to a wireless terminal device for each seat without installing a wiring cable such as a wired LAN system. It is possible to suppress the increase in weight due to and to change the layout of the flexible in-flight seat.

In addition, for example, in a wireless communication system used for consumer devices in a home, a technique that enables resource allocation of frequencies and bands so as not to cause interference in a consumer device group has been proposed (for example, Patent Documents). 2).
JP 2006-506899 A JP 2006-254398 A

  However, as in the conventional example of Patent Document 1 described above, one access point arranged in a small area and a plurality of wireless terminal devices in the small area time-divide the frequency band of one allocated channel. In the case of a wireless communication system that communicates with each other, the bandwidth per one wireless terminal device is narrowed along with the delay due to time division, and the response in such a conventional wireless communication system is extremely reduced. For this reason, the conventional wireless communication system is intended to be used for, for example, in-flight announcements for all passengers, PA (Passenger Address) which is cautions and explanations for emergencies, or emergency broadcasts that require immediacy. In such a case, there was a problem that the contents and information were not immediately transmitted to the passengers. That is, when such a content such as a movie or a music program is distributed using such a wireless communication system, although there is a delay at the start of distribution, it is in a delayed state when the program is started. Since delivery is performed continuously, such a delay due to a decrease in response is not a problem. On the other hand, the delivery service for all passengers is highly necessary to be transmitted instantly to all passengers.

  As a means for solving such a problem, it is conceivable that a service for all passengers such as an in-flight announcement uses a communication means corresponding to the entire in-flight. However, in this case, if communication corresponding to the entire area of the aircraft and communication for each small area as described above are mixed, interference and interference between the respective channels will occur unless the communication channel for the entire area and each small area is selected appropriately. There has been a problem that is likely to occur.

  In addition, the above-described conventional example of Patent Document 2 is a system configuration in which arbitration stations representing a plurality of wireless stations communicate with each other using a common channel. What is a system that distributes content using an access point? Because they are different, they are not suitable for content distribution systems on airplanes.

  The present invention has been made to solve the above-described problems, and can suppress interference and interference between channels assigned to each access point, and can immediately transmit specific content such as an in-flight announcement. An object is to provide a wireless communication system.

  In order to achieve the above-described object, a wireless communication system of the present invention is a wireless communication system that performs communication services by assigning a plurality of channels divided for each frequency in a target area. A first wireless base station device that provides communication services to wireless terminal devices included in the target area by assigning to the target area, and a channel other than the channel assigned to the target area by dividing the target area into a plurality of different small areas And a second wireless base station device for each small area that provides communication services to wireless terminal devices included in the small area, and the channels to be allocated to the target area are a plurality of channels divided in order of frequency. The channel is located at the end of the channel.

  Further, the wireless communication system of the present invention has a configuration in which an unused channel is provided between a channel assigned to a target area and an assigned channel for each small area.

  Further, the wireless communication system of the present invention has a configuration in which channels that are not continuous with each other are assigned to adjacent small areas.

  The radio communication system according to the present invention is a radio base station apparatus in which the first radio base station apparatus provides a wide area communication service with a radio terminal apparatus included in the target area as a cover area. A station apparatus is a radio base station apparatus that provides a small area communication service using a radio terminal apparatus included in a small area as a cover area, and the radio terminal apparatus includes a first radio base station apparatus and a second radio base station. It is the structure which communicates with both of apparatuses.

  The wireless communication system of the present invention is a wireless base station device that provides a wide area communication service in which the first wireless base station device covers the first wireless terminal device included in the target area. The radio base station apparatus is a radio base station apparatus that provides a small area communication service that covers the second radio terminal apparatus included in the small area.

  In the radio communication system of the present invention, the second radio base station apparatus divides one allocated channel in correspondence with each radio terminal apparatus in the small area and transmits data, and transmits the first radio base station. The station device is configured to simultaneously transmit data to the wireless terminal device in the target area using one allocated channel.

  Moreover, the radio | wireless communications system of this invention is the structure which made the object area the guest room area in the transport organization electromagnetically shielded from the outside.

  In the wireless communication system of the present invention, the channel assigned to the target area is a channel corresponding to the lowest frequency among a plurality of channels conforming to the IEEE 802.11a standard, which is one of the wireless LAN standards. It is.

  With such a configuration, the communication between the second radio base station apparatus and the radio terminal apparatus for each small area can distribute content that is not immediacy, and the first radio base station apparatus and the target area. The communication with all the wireless terminal devices included in the system enables transmission of in-flight announcements and the like, which are important for immediacy, and business communication for crew members. Also, since the channel used in the first radio base station apparatus is a channel located at the end of a plurality of channels divided in order of frequency, the channel used by the first radio base station apparatus and each second radio base Proximity interference and proximity interference due to the close proximity of the frequency with the channel used by the station apparatus can be suppressed.

  According to the wireless communication system of the present invention, it is possible to provide a wireless communication system that can suppress interference and interference between channels and can immediately transmit specific content such as an in-flight announcement.

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

(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of a radio communication system according to Embodiment 1 of the present invention. In the present embodiment, an example will be described in which the wireless communication system of the present invention is applied to a cabin area in an aircraft that is one of the transportation mechanisms electromagnetically shielded from the outside.

  As shown in FIG. 1, the wireless communication system according to the present embodiment includes a server device 10 that processes content data such as video and audio for distribution and notification, and a plurality of access point devices connected to the server device 10 respectively. 20, one access point device 30 connected to the server device 10, and a plurality of wireless terminal devices 40 that perform wireless communication with the access point device 20 and the access point device 30.

  Further, when all areas to be communicated by the wireless communication system in the aircraft are set as the target area, in the present embodiment, the target area is divided into a plurality of different small areas. That is, the aircraft is divided into such small areas, one access point device 20 is arranged in each small area, and the access point device 20 communicates with a plurality of wireless terminal devices 40 included in the small area. It has a simple structure. FIG. 1 shows an example in which the target area is divided into n small areas from the small area A1 to the small area An. In addition to the arrangement of the access point device 20 for each small area, in this embodiment, the access point device 30 that can communicate with all the wireless terminal devices 40 included in the target area is also arranged. It is a feature.

  With such a basic configuration, the wireless communication system according to the embodiment of the present invention arranges a content such as a movie or a music program desired by a passenger from the server device 10 via the access point device 20 in front of each passenger's seat. And in-flight announcements for all passengers are notified from the server device 10 to the wireless terminal devices 40 via the access point device 30.

  In order to implement such communication services as content distribution and in-flight announcements, in the wireless communication system according to the present embodiment, first, the server device 10 distributes individual content such as programs desired by each passenger. The configuration includes a unicast server device 12, a distribution device 11 that controls connection between the unicast server device 12 and each access point device 20, and a multicast server device 13 that performs in-flight announcements for all passengers at once. is there.

  In the server device 10, the unicast server device 12 distributes individual contents as desired by each passenger to each wireless terminal device 40. That is, the unicast server device 12 is a server for performing so-called unicast for distributing content to a specific partner. In order to perform such processing, the unicast server device 12 holds content data that is video data and audio data such as movie programs and music programs. In addition, since the distribution device 11 distributes the content desired by the passenger to the wireless terminal device 40 corresponding to the passenger, the access point device 20 and the unicast server device 12 in the small area in which the wireless terminal device 40 is included, Is controlled so as to establish communication connection, whereby the content data of each program held in the unicast server device 12 is distributed to each access point device 20.

  Moreover, in the server apparatus 10, the multicast server apparatus 13 implements a simultaneous service for all passengers via all the wireless terminal apparatuses 40 in the target area. That is, the multicast server device 13 is a server for performing so-called multicast for transmitting data to a plurality of partners. Since the multicast server device 13 performs services for a plurality of opponents, that is, all passengers, the multicast server device 13 holds, for example, emergency content to be used before takeoff and content data of the PA, which is an explanation matter, before takeoff, It processes live images outside the aircraft during landing, and real-time audio such as in-flight announcements. Thus, the video and audio data generated by the processing of the multicast server device 13 is transmitted to the access point device 30.

  Each access point device 20 is connected to the distribution device 11 of the server device 10 by a wired cable or the like. The access point device 20 is a wireless base station device provided for wireless connection with the wireless terminal device 40. In the wireless LAN system as described above, a base station called an access point that provides such wireless connection is installed in order to connect the terminal device and the server using wireless. As one form of use of a wireless LAN system, there is a system in which a plurality of terminal devices wirelessly connected to an access point centering on such an access point communicate. In the present embodiment, in each small area centering on the access point device 20, a wireless LAN system in which the access point device 20 and each wireless terminal device 40 in the small area are connected by data is configured. As described above, the wireless communication system according to the present embodiment divides the in-flight space into a plurality of small areas, and each access point is provided so that one access point device 20 corresponds to one small area. The device 20 is assigned in the plane, and a wireless LAN system is configured in each small area. Furthermore, an optimal channel is allocated to each small area in order to suppress interference and failure in such wireless communication between the small areas. The channel assignment will be described in detail below. Further, in order to transmit individual content data to each wireless terminal device 40 in the small area, the access point device 20 divides one channel, for example, in a time division manner, to each wireless terminal device 40. Transmit content data. The wireless terminal device 40 temporarily stores the content data received in a time division manner and reproduces it while sequentially restoring it to video and audio data. The video and audio reproduced by the wireless terminal device 40 are presented to the passenger.

  The access point device 30 is connected to the multicast server device 13 of the server device 10 by a wired cable or the like. The access point device 30 is a wireless base station device provided for wireless connection with all the wireless terminal devices 40 installed in the aircraft. That is, in the present embodiment, a wireless LAN system in which the access point device 30 and each wireless terminal device 40 are data-connected is configured in a target area centered on the access point device 30. In this way, the access point device 30 covers the entire target area, and simultaneously transmits data to all the wireless terminal devices 40 in the target area using one channel as described below. In particular, when the wireless communication system is applied to an aircraft as in the present embodiment, the aircraft is generally covered with a lightweight aluminum alloy, that is, a metal. For this reason, even a radio wave emitted from one access point as in the access point device 30 is the same as radio communication being performed in a shielded room. Therefore, the wireless LAN system centering on the access point device 30 can be constructed.

  As described above, the wireless communication system according to the present embodiment is different from the access point device 30 as the first wireless base station device that provides communication services to the wireless terminal device 40 included in the target area. An access point device 20 is provided as a second radio base station device for each small area that is divided into small areas and provides communication services to the radio terminal devices 40 included in the small area. The access point device 30 is an access point device that provides a wide area communication service with the wireless terminal device 40 included in the target area as a cover area. The access point device 20 includes the wireless terminal device 40 included in the small area. The wireless terminal device 40 communicates with both the access point device 30 and the access point device 20. The wireless terminal device 40 is an access point device that provides a small area communication service as a cover area.

  Next, allocation of channels used by each access point device 20 and access point device 30 will be described. In the present embodiment, an example is given in which channel assignment is set under the following conditions. First, as a first condition, one channel is assigned to the target area in order to avoid communication interference from the access point device 30 to each small area. As a second condition, in order to suppress interference between adjacent channels and frequency adjacent interference, adjacent channels are not allocated between the target area and each small area and between adjacent small areas. The channel allocation set based on such conditions will be described.

  FIG. 2 is a diagram showing an example of channel assignment in the wireless communication system of the present embodiment set based on such conditions. Here, an example is shown in which channels having a predetermined bandwidth and can be used for nine channels as indicated by 01ch to 09ch divided for each frequency.

  In this embodiment, in order to assign a channel from such a plurality of channels to each area, first, in order to satisfy the first condition described above, the access point device 30 covering the target area is set to 09 ch. One channel is assigned as the channel for the entire area. In particular, in this channel assignment, the present embodiment is characterized in that a channel located at the end of a plurality of channels divided in order of frequency, such as 09ch, is assigned as a channel for the entire area. In other words, the channel corresponding to the lowest frequency or the highest frequency is assigned to the access point device 30 among the plurality of channels divided in order of frequency.

  Next, in order to satisfy the second condition described above, as shown in FIG. 2, channel 08 is set as an unused channel, and adjacent channels are not assigned between the target area and each small area. Further, with such a setting, a channel excluding a channel assigned to the target area and its adjacent channel is assigned to each small area. That is, in FIG. 2, a plurality of channels from 01ch to 07ch are assigned to each small area. In place of the assignment shown in FIG. 2, the channel corresponding to the lowest frequency, 01ch, is assigned as the channel for the entire area, 02ch is set as an unused channel, and other channels from 03ch to 09ch are assigned to each small area. It may be configured to be assigned to.

  Next, channel assignment between adjacent small areas under the second condition described above will be described.

  FIG. 3 is a diagram illustrating an example of area division in the aircraft 100 and channel assignment to each area. FIG. 3 shows an example in which 09ch shown in FIG. 2 is assigned to a target area that can communicate with all the wireless terminal devices 40 from the access point device 30 in the aircraft 100. In FIG. 3, the aircraft 100 is divided into small areas centered on 11 access point devices 20 such as small areas A1 to A11, and the seven channels from 01ch to 07ch shown in FIG. An example of assignment to each small area is shown. That is, first, 01ch is assigned to the first small area A1. Next, on the basis of the second condition described above, the adjacent small area A2 is assigned to the 01ch, which is not an adjacent channel, 03ch. Next, 05ch that is not an adjacent channel is assigned to 03ch to the small area A3 adjacent to the small area A2. Further, 07 ch is assigned to the adjacent small area A4, and then 02 ch is assigned to the adjacent small area A5 by returning to the lower channel. As described above, in FIG. 3, channels are allocated in such a manner that the 7 channels from 01ch to 07ch are skipped one by one in order from the small areas A1 to A11, so that the adjacent small areas are adjacent to each other. It is set not to become a channel. Further, by adopting such a channel arrangement between the small areas, a limited number of channels are reused in the aircraft 100, and interference and interference between channels assigned to the small areas are suppressed. Note that the channel arrangement between the small areas shown in FIG. 3 is an example, and other channel arrangements may be used as long as the second condition that the channels between the small areas do not continue is satisfied.

  By the way, as a method of satisfying the first condition described above, for example, a mode in which the channel for the entire area is arranged in the center of the usable channel is conceivable. In this case, the channel for the entire area is satisfied in order to satisfy the second condition. It is necessary to make the channels adjacent to each other unused channels. Specifically, for example, in the case of 05 ch in 01 ch to 09 ch in FIG. 2, the channel for all channels needs to be unused channels for 04 ch and 06 ch in order to satisfy the second condition. On the other hand, by arranging the channel for the entire area at the end in the usable channel as in the present embodiment, only one channel may be set as an unused channel. For this reason, as for the number of channels allocated to each small area, the present embodiment in which the channel for the whole area is arranged at the end can secure one channel more than the mode in which the channel for the whole area is arranged near the center. As a result, in this embodiment, compared with the mode in which the channel for the entire area is arranged near the center, the channel assignment of the small area can be performed more flexibly, and the distance between the small areas that are the same channel is also more distant. can do. For this reason, it is possible to further suppress interference and interference between the same frequencies as compared with the case where the channel for the entire area is a channel near the center.

  FIG. 4 is a diagram showing a specific example of channel assignment for communication by the wireless communication system in the first embodiment of the present invention. Here, an example is shown in which each channel is assigned to a channel defined by IEEE 802.11a. As a frequency band used in the wireless LAN, a 2.4 GHz band or a 5 GHz band is generally used, but FIG. 4 shows an example of channel use in the 5 GHz band based on IEEE802.11a. As shown in FIG. 4, in the current 5 GHz band, in addition to 36, 40, 44 ch, and 48 ch, there are 8 channels for 52, 56, 60 ch, and 64 ch that are DFS (Dynamic Frequency Selection) targets. Channels are assigned. Note that DFS is a function of automatically changing the setting to another channel in order to avoid interference, and such a DFS target channel may be changed. In addition, when using the 5 GHz band for aircraft internal communication as in the present embodiment, for example, in a flight state exceeding 10,000 meters, there is no possibility of interference, so DFS may not be applied. In the case of low altitude flight such as takeoff or landing, DFS may be applied. For this reason, as shown in FIG. 4, among the channels, DFS is not applied and 36 ch having the lowest frequency corresponding to the channel located at the end is assigned to the target area as the channel for the entire area, and 40 ch is not yet assigned. The other 6 channels are assigned to each small area as used channels. When the 5 GHz band is used, such a channel assignment does not cause a change in the channel for the entire area that is also used for emergency broadcasts and the like, so that stable operation can be provided.

  Next, the operation of the wireless communication system according to the present embodiment will be described. First, distribution of contents such as movies and music programs using the access point device 20 is performed as follows. That is, when a passenger requests content distribution of a desired program using, for example, the wireless terminal device 40 installed in front of the seat, request data indicating the request is transmitted from the wireless terminal device 40 to the wireless terminal. The access point device 20 arranged in a small area including the device 40 is notified. Further, the request data is notified to the unicast server device 12 via the access point device 20 and the distribution device 11. The unicast server device 12 analyzes the request data from the wireless terminal device 40 and interprets the identification information of the wireless terminal device 40 corresponding to the passenger and the content data requested by the passenger. Further, the unicast server device 12 sends the requested content data to the wireless terminal device 40 of the read identification information. Based on the identification information of the wireless terminal device 40, the distribution device 11 sends the content data to the access point device 20 in the small area including the wireless terminal device 40 of the identification information. In addition, since such processing is executed in a time division manner for each wireless terminal device 40, individual content data for each passenger is distributed to each wireless terminal device 40. A desired movie or the like can be viewed from the wireless terminal device 40 installed in the front seat.

  Also, for example, before the departure of the aircraft, PA such as cautions and explanation items in emergency for all passengers is performed. In such a case, in the wireless communication system of the present embodiment, PA is implemented using the multicast server device 13 and the access point device 30. That is, first, information indicating the start of communication in the entire target area is notified from the multicast server device 13 via the access point device 30 to all the wireless terminal devices 40 using the channel for the entire area. Then, each wireless terminal device 40 switches to presentation of video and audio by communication with the access point device 30 based on information indicating the start of communication in the entire area. Thereby, the video and audio data of the emergency caution and explanation items from the multicast server device 13 are notified to all the wireless terminal devices 40, and the video and audio are presented to each passenger. At this time, as described above, since communication using the access point device 30 is simultaneous delivery and notification to all passengers, there is no need for processing for distributing individual content data by time division, and all wireless communication is performed. The terminal device 40 can be notified of PA or the like immediately. Further, when the PA for all passengers is completed, each wireless terminal device 40 switches to presentation of video and audio by communication with the access point device 20 in a small area including the wireless terminal device 40.

  As described above, the radio communication system according to the present embodiment is a radio communication system that performs communication services by assigning a plurality of channels divided by frequency in a target area. In this way, the access point device 30 as the first radio base station device that allocates one channel to the target area and provides the communication service to the radio terminal device 40 included in the target area, and the target area as a plurality of different small areas A channel other than the channel assigned to the access point device 30, that is, a channel such as 01ch to 07ch shown in FIG. 2 is assigned to each small area, and communication service is provided to the wireless terminal device 40 included in the small area. As a second radio base station device for each small area And a winding device 20, the channel to be allocated to the access point device 30 is a channel like 09ch in FIG. 2, for example on the edge of the plurality of channels divided in order of frequency.

  Since the wireless communication system of the present embodiment has such a configuration, the contents of movie programs and music programs whose immediacy is not important due to communication between the access point device 20 and the wireless terminal device 40 for each small area. And communication between the access point device 30 and all the wireless terminal devices 40 included in the target area enables transmission of in-flight announcements in which immediacy is important. Further, since the channel used in the access point device 30 is a channel located at the end of a plurality of channels divided in order of frequency, the frequency of the channel used by the access point device 30 and the channel used by each access point device 20 Proximity interference and proximity interference due to the proximity of each other can be suppressed. Therefore, according to the wireless communication system of the present invention, it is possible to provide a wireless communication system that can suppress interference and interference between channels and can immediately transmit specific content such as an in-flight announcement.

(Embodiment 2)
FIG. 5 is a block diagram showing a configuration of a radio communication system according to Embodiment 2 of the present invention. Also in this embodiment, an example will be described in which the wireless communication system of the present invention is applied to a cabin area in an aircraft that is one of the transportation mechanisms electromagnetically shielded from the outside. In addition, in comparison with FIG. 1, the present embodiment further includes a wireless terminal device 50 that is intended for flight attendants and the like, and the server device 10 replaces the multicast server device 13 of FIG. The apparatus 19 is provided with a configuration.

  In the present embodiment, by providing a radio communication system with a configuration as shown in FIG. 5 in the aircraft, a content distribution service and the like are implemented for each passenger via the radio terminal device 40 provided in each seat, Business communication between the server device 19 for crew and the wireless terminal device 50 held by the cabin crew is performed. In FIG. 5, the same reference numerals as those in FIG. 1 denote the same components, and detailed description thereof will be omitted. Also, channel assignment and area division are the same as in the first embodiment, and detailed description thereof is omitted.

  In FIG. 5, a crew member server device 19 included in the server device 10 is a server that processes communication between crew members. The crew server device 19 is connected to the access point device 30 by a wired cable or the like. As described in the first embodiment, the access point device 30 is an access point that covers communication with the wireless terminal device in the target area using the channel for the entire area shown in FIG. In the present embodiment, data connection is made between the access point device 30 and the wireless terminal device 50 as the first wireless terminal device held by the crew in the target area. On the other hand, the unicast server device 12 included in the server device 10 is connected to each wireless terminal device 40 as a second wireless terminal device installed for passengers via the distribution device 11 and each access point device 20 and data connection. Is done. In the present embodiment, each wireless terminal device 40 is data-connected only to the unicast server device 12.

  As described above, the wireless communication system according to the present embodiment is an access point device in which the access point device 30 provides business communication using the wireless terminal device 50 included in the target area as a cover area. Is an access point device that provides a small area communication service with the wireless terminal device 40 included in the small area as a cover area.

  Next, the operation of the wireless communication system according to the present embodiment will be described. First, distribution of content such as a movie or a music program using the access point device 20 is performed in the same manner as in the first embodiment. Thereby, individual content data for each passenger is distributed, and the passenger can view a desired movie or the like from the wireless terminal device 40 installed in the front seat, for example.

  Further, for example, in order to perform meal services for passengers, the cabin crew moves within the target area shown in FIG. At this time, since each flight attendant holds the wireless terminal device 40 that is connected to the access point device 30, for example, the chief flight attendant calls a flight attendant who is moving from the terminal of the crew member server device 19 and information data. Can communicate. At this time, as described above, since communication using the access point device 30 is communication for business for crew members, processing for distributing individual content data by time division is not necessary, and each guest room It is possible to immediately communicate with the radio terminal device 40 of the crew member. Further, since communication using the access point device 30 is performed in the channel assignment shown in FIG. 2 and the area division as shown in FIG. 3, the radio communication system of the present embodiment also provides interference between channels. And interference can be suppressed.

  As described above, the radio communication system according to the present embodiment is a radio communication system that performs communication services by assigning a plurality of channels divided by frequency in a target area. As described above, an access point device 30 as a first radio base station device that allocates one channel to a target area and provides a communication service to the radio terminal device 50 included in the target area, and a plurality of different small areas A channel other than the channel assigned to the access point device 30, that is, a channel such as 01ch to 07ch shown in FIG. 2 is assigned to each small area, and communication service is provided to the wireless terminal device 40 included in the small area. As a second radio base station device for each small area And a winding device 20, the channel to be allocated to the access point device 30 is a channel like 09ch in FIG. 2, for example on the edge of the plurality of channels divided in order of frequency.

  Since the wireless communication system of the present embodiment has such a configuration, the contents of movie programs and music programs whose immediacy is not important due to communication between the access point device 20 and the wireless terminal device 40 for each small area. And communication between the access point device 30 and the wireless terminal device 50 included in the target area enables transmission of business communication between crew members in which immediacy is important. In addition, since the channel used in the access point device 30 is a channel located at the end of a plurality of channels divided in order of frequency, the channel used by the access point device 30 and the channel used by each access point device 20 Proximity interference and proximity interference due to close frequency can be suppressed. Therefore, according to the wireless communication system of the present invention, it is possible to provide a wireless communication system that can suppress interference and interference between channels and can immediately transmit specific content such as an in-flight announcement.

  In the above description, an example is described in which one access point device 30 covers the entire area of the aircraft. However, for example, a work area such as a kitchen in which the cabin crew, which is called a galley, provides services. If it is partitioned by a galley, there is a high possibility that radio waves are blocked by the galley. In such a case, the configuration may be such that the access point device 30 of the same channel is installed for each guest room area partitioned by the galley. On the other hand, if the galley does not block the radio wave, or if the access point device cannot cover the entire area of the aircraft like the access point device 30 in FIG. The configuration may be such that an unused channel is provided and assigned to an access point apparatus that provides the entire area communication service. Further, for example, when two access point devices are arranged as a global communication service, a configuration may be adopted in which the highest frequency is assigned to one and the lowest frequency is assigned to the other. That is, when two access point devices 30A and 30B are installed for the entire area communication service, 09ch shown in FIG. 2 is assigned to the access point device 30A, and 08ch is set as an unused channel. 2 may be configured such that 07ch shown in FIG. 2 is assigned, 06ch is an unused channel, and 01ch to 05ch are assigned to each small area. Further, 09ch shown in FIG. 2 is assigned to the access point device 30A, 08ch is set as an unused channel, and 01ch shown in FIG. 2 is assigned to the access point device 30B, and 02ch is set as an unused channel. The configuration may be such that 07ch is assigned to each small area.

  In the above description, for example, one bandwidth in the vicinity of 5 GHz has been described as being divided into channels as shown in FIG. 4. However, a plurality of bandwidths are allocated, and each bandwidth is assigned to each channel. Needless to say, in the case of a wireless channel classified as follows, it may be handled as follows. That is, for example, in the case of 5 GHz band in the United States in wireless LAN, it is divided into three bandwidths such as 36 ch to 64 ch, 100 ch to 140 ch, 149 ch to 161 ch, and such a channel is assigned to each band. The channel is usable. For such a channel-assigned wireless LAN, the channels located at the ends of a plurality of channels divided in order of frequency may be 64ch, 100ch, 140 and 149ch in addition to 36ch and 161.

  In the above description, an example applied to a cabin area in an aircraft has been described as an example of the wireless communication system of the present invention provided in a transportation facility, but electromagnetically from the outside such as a train or a bus. The radio communication system of the present invention can also be applied to an electromagnetically shielded room.

  The present invention can provide a wireless communication system that can suppress interference and interference between channels and can immediately transmit specific contents such as in-flight announcements. It can be used for a system that provides an information distribution service.

1 is a block diagram showing a configuration of a wireless communication system according to Embodiment 1 of the present invention. The figure which showed an example of the channel allocation of the radio | wireless communications system The figure which showed an example of the division of the area in an airplane, and the allocation of the channel to each area The figure which showed the specific example of the channel allocation of the radio | wireless communications system in Embodiment 1 of this invention. FIG. 3 is a block diagram showing a configuration of a wireless communication system according to Embodiment 2 of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Server apparatus 11 Distribution apparatus 12 Unicast server apparatus 13 Multicast server apparatus 19 Crew server apparatus 20, 30 Access point apparatus 40, 50 Wireless terminal apparatus 100 Aircraft

Claims (8)

In a target area, a wireless communication system that performs communication services by allocating a plurality of channels divided for each frequency,
A first radio base station apparatus that allocates one channel to the target area and provides a communication service to a radio terminal apparatus included in the target area;
For each small area that divides the target area into a plurality of different small areas, assigns a channel other than the channel assigned to the target area for each small area, and provides a communication service to a wireless terminal device included in the small area A second radio base station apparatus,
The radio communication system according to claim 1, wherein the channel assigned to the target area is a channel located at an end of a plurality of channels divided in order of frequency. The wireless communication system according to claim 1, wherein an unused channel is provided between a channel assigned to the target area and an assigned channel for each small area. 3. The wireless communication system according to claim 2, wherein channels adjacent to each other in the adjacent small area are assigned channels that are not continuous with each other. The first radio base station apparatus is a radio base station apparatus that provides a wide area communication service with a radio terminal apparatus included in the target area as a cover area,
The second radio base station apparatus is a radio base station apparatus that provides a small area communication service that covers a radio terminal apparatus included in the small area.
4. The wireless communication system according to claim 1, wherein the wireless terminal device communicates with both the first wireless base station device and the second wireless base station device. 5. . The first radio base station apparatus is a radio base station apparatus that provides a wide area communication service that covers a first radio terminal apparatus included in the target area.
The second radio base station apparatus is a radio base station apparatus that provides a small area communication service that covers a second radio terminal apparatus included in the small area. The wireless communication system according to any one of the above. The second radio base station apparatus divides one allocated channel in association with each radio terminal apparatus in the small area and transmits data, and the first radio base station apparatus is allocated The wireless communication system according to claim 4 or 5, wherein simultaneous data transmission is performed to the wireless terminal device in the target area using one channel. The wireless communication system according to claim 6, wherein the target area is a cabin area in a transportation facility that is electromagnetically shielded from the outside. 8. The channel allocated to the target area is a channel corresponding to the lowest frequency among a plurality of channels conforming to the IEEE 802.11a standard which is one of wireless LAN standards. Wireless communication system.

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