JP2002141857A - System and method for radio communication and portable terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem that an adverse influence is exerted upon a person wearing a pacemaker or the like since the high frequency of comparatively large power is outputted when a portable telephone is used in congestion such as in the train. SOLUTION: A wireless LAN environment is constructed by interposing a repeater station 12 between a base station 11 and a portable terminal 13, communication is performed between the repeater station 12 and the portable terminal 13 in the high frequency of smaller output compared with the case between the base station 11 and the portable terminal 13. Further, inside the wireless LAN environment, communication between the repeater station 12 and the portable terminal 13 is dealt more preferentially compared with communication between the base station 11 and the portable terminal 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication system, a wireless communication method, and a portable terminal, and more particularly, to a portable mobile telephone (hereinafter, simply referred to as a portable telephone) and a PDA (Performance).
The present invention relates to a wireless communication system and a wireless communication method for performing communication between a mobile terminal such as sonal digital assistants) and a base station, and a mobile terminal used in the wireless communication system.

[0002]

2. Description of the Related Art In recent years, with the rapid progress of computerization, portable terminals such as portable telephones and PDAs have become remarkably popular, and portable telephones in particular have become necessities of daily life. This mobile phone is
Because it is necessary to communicate with a remote base station, several hundred meters
It has a relatively large high-frequency output of about W. Also,
For example, when a mobile phone is used in a train, communication is performed with a particularly large high-frequency output because the vehicle body has a shielding effect and a received radio wave tends to be weak.

On the other hand, recently, in consideration of people with medical equipment such as pacemakers, announcements have been made so as to refrain from using mobile phones in crowds such as in trains. As a manner, handling high-output high-frequency waves (radio waves) in person is becoming a problem.

[0004]

However, even if an announcement is made so as to refrain from using a mobile phone, the mobile phone is currently used even in crowded places such as in trains, simply ignoring it. is there. In addition, in many cases, such as in an emergency, it is often necessary to contact a distant outside, and this can be achieved by a mobile terminal such as a mobile phone.

[0005] Also, in crowds such as in trains, speaking through a mobile phone is one of the problems as social manners. From this point of view, it seems that there is no problem when exchanging e-mail using a mobile phone or exchanging data using a portable information terminal such as a PDA because there is no conversation there. However, even when exchanging e-mails and data, there is no difference in that communication between the portable terminal and the base station is performed at a high output high frequency. Therefore, from the viewpoint of consideration for a person with a medical device such as a pacemaker, no problem has been solved at present.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a wireless communication system and a portable communication system capable of performing communication without using a high-output high frequency when crowded in a train or the like. To provide a terminal.

[0007]

SUMMARY OF THE INVENTION A radio communication system according to the present invention performs communication between a base station and a portable terminal with the base station, and uses a first high frequency used for communication with the base station. Also employs a configuration in which a relay station having a low output and capable of communicating with a second high frequency that can be distinguished from the first high frequency is interposed. The mobile terminal has the ability to communicate with the base station, but within the communicable area of the relay station, gives priority to communication with the relay station at the second high frequency of low output, and via the relay station. Communicates with the base station.

[0008] In the wireless communication system having the above-described configuration, the relay station is installed in a moving body such as a train, or in a building such as a hospital or a station. When the mobile terminal is used in a moving body or in a building, the mobile terminal is located within the communicable area of the relay station, that is, in the wireless network environment constructed by the relay station, so that the mobile terminal is used for communication with the base station. Priority is given to communication with the relay station, and communication with the relay station is performed at a relatively low output high frequency. When the mobile terminal exits from a moving object, building, or the like, the mobile terminal is out of the communicable area of the relay station.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

[First Embodiment] FIG. 1 is a conceptual diagram showing a configuration example of a wireless communication system according to a first embodiment of the present invention. As is apparent from FIG. 1, the wireless communication system according to the present embodiment includes a base station 11, a relay station 12 installed in a moving body such as a train, or a building such as a hospital, department store, or station yard, and a mobile phone. And a mobile communication system having a mobile terminal 13 such as a PDA.

The base stations 11 are installed at intervals of about several kilometers in a service providing area. More specifically, the base station is installed so that the geographical area in which one base station is in charge of communication, that is, the area covered by the cell does not overlap as much as possible, and there is no point that is not covered by any base station. The base station 11 includes the relay station 12 and the portable terminal 1.
It has a function of converting call information such as voice transmitted and received between the network 3 and the network and control information into wireless signals and transmitting them, a function of managing and controlling wireless channel resources and terminals in the zone, and the like.

Base station 11, relay station 12, and portable terminal 1
For example, IMT-2000 (next-generation mobile communication) is used as a communication method on the wireless communication line between the mobile communication device 3 and the mobile communication device 3. In addition, since it is necessary to communicate with the remote relay station 12 and the mobile terminal 13, it has a relatively large high-frequency output of several W or more. The assignment of the frequency band will be described later.

Here, the base station 11 and the relay station 12
IMT-2 as a communication system between the mobile terminal 13 and
000 is used as an example, but the present invention is not limited to this, and PDC (Personal Digital
gital Cellular) and GSM (Glob
al System for Mobile Communications).

The relay station 12 includes a base station 11 and a portable terminal 13.
In order to relay data between a local area network and a moving body such as a train or a building such as a hospital,
k) Build the environment. When the relay station 12 is installed in a train, for example, as shown in FIG.
5 and the relay station 12 may be installed, for example, on a ceiling portion of each vehicle to construct a wireless LAN environment. Also, hospitals, department stores,
When installed in a building such as a station yard, an external wireless antenna may be installed on a rooftop, and a wireless LAN environment may be constructed by installing, for example, a relay station 12 on a ceiling or the like for each floor. .

The relay station 12 communicates with the base station 11 and also communicates with the portable terminal 13 located within its own communicable area. The mobile terminal 13 can transmit data at a lower output than the high frequency used for communication with the base station 11, for example, about several tens of mW, and preferably at a higher speed than a conventional mobile phone system. At the same time, communication is performed at a high frequency having a different frequency band from the high frequency used for communication with the base station 11. The assignment of the frequency band will be described later.

Incidentally, when crowded in a train or the like, a plurality of portable terminals 13 may naturally exist in the communicable area for one relay station 12. Therefore, the relay station 12 has a plurality of channels having different frequencies to enable simultaneous communication with a plurality of portable terminals. Then, in order to avoid interference, a configuration is employed in which a search is made for a communicable vacant channel at all times, and when there is no vacant channel, an operation of returning a busy signal to the base station 11 is performed.

The mobile terminal 13 has a function of communicating with the base station 11 and a communication with the relay station 12 when the mobile terminal 13 is located within a communicable area of the relay station 12 with low output radio waves. And a function for performing indirect communication with the base station 11 via the relay station 12 with priority given to direct communication with the base station 11. These functions are realized under the control of a control unit (not shown) configured using a built-in microcomputer or the like.

FIG. 3 shows an example of the configuration of the portable terminal 13. The mobile terminal 13 according to the present example includes a mobile phone function and a PD.
It has the function of A.

In FIG. 3, on the front face of the terminal body 21,
A display unit 22 made of liquid crystal or the like having a size of several cm square or more is provided, and control buttons 23 are arranged below the display unit 22. A part of the display unit 22 is a pressure-sensitive unit 24 for inputting characters by handwriting with an electronic pen or the like. The pressure sensing unit 24 is configured by a known means such as a resistance film. A jog dial 25 for selecting various functions is provided on a side surface of the terminal body 21.

In the terminal body 21, a relatively large-output long-distance wireless interface 26 used for communication with the base station 11 and a communication between the relay station 12 and the relay station 12 are used. A relatively small output short-range wireless interface 27
And built-in. Further, the mobile terminal 13 according to the present embodiment has a configuration in which voice input / output is performed by a voice input / output device provided separately from the terminal body 21.

As shown in FIG. 4, a voice input / output device separate from the terminal main body 21 is connected to the terminal main body 2 via a weak radio line.
Two devices are considered: a rod-shaped input / output device (hereinafter referred to as a voice stick) 28 connected to the device 1 and a headset 29 connected to the terminal body 21 via a wired line. A configuration in which both the voice stick 28 and the headset 29 are provided may be adopted, or a configuration in which one of them is provided may be adopted.

In the case of adopting a configuration having both the voice stick 28 and the headset 29, for example, the wired side, that is, the headset 29 is prioritized, and the plug of the wired line is used.
When (not shown) is attached to the terminal body 21, the wireless interface (IF) is normally disabled.
However, the present invention is not limited to this, and a mode for operating both of them at the same time may be prepared, or a mode for giving priority to the wireless side, that is, the voice stick 28 may be prepared.

Terminal body 21 and voice stick 28
In the wireless line between the relay station 12 and the mobile terminal 13, a high-frequency power which is weaker than that used for communication between the relay station 12 and the mobile terminal 13, that is, a weak radio wave (for example, about several mW) is used. The terminal main body 21 also has a built-in wireless interface 30 for weak radio waves used for communication with the voice stick 28. As the wireless interface 30 for a weak radio wave, Bluetooth
h or a known interface such as a cordless telephone interface.

Incidentally, in crowded places such as in a train, it is naturally possible that a plurality of portable terminals 13 simultaneously communicate within the communicable area of one relay station 12. At this time, if a configuration is adopted in which each of the plurality of mobile terminals 13 is connected to the voice stick 28 by a wireless line, the frequency that can be used for the wireless line within one communicable area is limited. Interference occurs.

Therefore, the wireless interface 30 for the weak radio wave is transmitted to the relay station 1 without causing interference with the voice stick 28 of another portable terminal.
2 has a plurality of channels having different frequencies to enable simultaneous communication. Then, in order to avoid interference, a search is always made for an available vacant channel, and if no vacant channel exists, the busy signal is transmitted to the relay station 1.
In this configuration, an operation of returning a response to the base station 11 via the communication line 2 is performed.

The voice stick 28 includes a microphone and a speaker (both not shown) and a wireless interface (not shown) for communicating with a weak radio wave wireless interface 30 in the terminal body 21. Of course, as shown in FIG. 5, an input button 31 and a display unit 32 for confirming input data from the button 31 are provided on the front side, and a breast pocket of clothes is provided on the back side. Is provided with a clip 33 for fixing the clip.

The current mobile phone is large and heavy for putting it in a pocket such as a chest of clothes, and if it is put in a bag or a shoulder bag, it will not be possible to respond quickly when receiving. On the other hand, Voice Stick 2
8 is small and lightweight, so that it can be easily inserted into a pocket such as a chest of clothes, and even if the terminal body 21 is put in a bag or a shoulder bag, the voice stick 28 can be used. Since transmission and reception can be easily performed, the portable terminal 13 can be carried around smartly in design.

The voice stick 28 has a built-in rechargeable battery. When the voice stick 28 is attached to the terminal body 21, power is supplied from the battery in the terminal body 21 to the voice stick 28 as necessary, and if necessary, the power is supplied to the voice stick 28 in the terminal body 21. The battery of the voice stick 28 is charged by the battery.

The terminal body 21 of the portable terminal 12 and the voice
In the situation where the voice stick 28 is operating in relation to the stick 28, when the number of the communication destination is input on the terminal main body 21 side, this is displayed on the display section 22 of the terminal main body 21 side and the wireless IF is connected. The voice is also transmitted to the voice stick 28 via the voice stick 28 and is also displayed on the display unit 32 on the voice stick 28 side. Conversely, voice
When a contact number is input on the stick 28 side, the number is displayed on the display unit 32 of the voice stick 28 and transmitted to the terminal body 21 via the wireless IF, and is displayed on the display unit 22 of the terminal body 21 side. Is also displayed.

Here, communication between the base station 11, the relay station 12, and the portable terminal 13, the relay station 12 and the portable terminal 13
Different frequency bands are assigned as high frequency (radio wave) bands used for communication between the mobile terminal 13 and the voice stick 28 (FDM; Fr).
equency Division Multiplex). As a result, it is possible to independently set a wireless line in each communication system.

As an example, in the case where IMT-2000 is used as the communication system of the mobile phone system, as shown in FIG. 6, the base station 11, the relay station 12, and the mobile terminal 1
2.0 GHz is allocated to a relatively high-output radio wave used for communication with the wireless interface 26 of the third station, and the comparison is performed for communication between the relay station 12 and the wireless interface 27 of the portable terminal 13. 5.2 for very low power radio waves
GHz is allocated, and 2.4 GHz is allocated to a weak radio wave used for communication between the wireless interface 30 of the portable terminal 13 and the voice stick 28.

As shown in FIG. 7, the time using one radio frequency is divided on the time axis to provide a time slot (time frame) in the transition of time, and communication is performed in different time slots. At a specific timing, TDMA (Time Divisi) for performing communication (signal transmission) only on a specific wireless line.
on Multiple Access). As shown in the figure, when the mobile terminal 13 switches between communication with the relay station 12 and communication with the voice stick 28, the magnitude of the high-frequency power is also controlled.

As described above, in the mobile communication system according to the present embodiment, the portable terminal 13 is a voice stick 28 separate from the terminal body 21 as a voice input / output device.
, And communication between them is performed by a wireless line, so that three wireless interfaces are provided in the terminal body 21, that is, a long-range wireless interface 26 having a relatively large output and a wireless interface 26 having a relatively small output. Short range wireless interface 27
And a radio interface 30 for weak radio waves.

The three wireless interfaces 26 and 2
Reference numerals 7 and 30 respectively denote the FDM method shown in FIG.
Since a frequency band is assigned to each high frequency, it is necessary to selectively receive radio waves in each frequency band.
To do so, generally three wireless interfaces 2
Configurations 6, 7, 30 each having a demodulation function corresponding to a specific communication wave can be considered.

As another configuration, a so-called software receiver which can transmit and receive radio waves of various communication systems with one common hardware device by using a signal processing software program stored therein can be considered. This software receiver, as shown in FIG.
1, a configuration including a broadband receiving unit 42, a D / A converter 43, and a digital signal processing circuit (DSP) 44.

The broadband receiving section 42 receives at least 2.0 GHz, 2.4 GHz, and 5.2 GHz through the antenna 41.
After receiving a wideband radio wave (RF signal) including z, performing signal amplification and band limitation processing, the RF signal
Convert to a signal and output. The D / A converter 43 converts an analog signal output from the broadband receiver 42 into a digital signal and supplies the digital signal to a digital signal processing circuit 44.

The digital signal processing circuit 44 has a memory (not shown) for storing a software program for signal processing. Based on the software program stored in this memory, various modulation formats and various protocols are stored. And demodulation processing of the communication wave. The software program for signal processing can be rewritten from outside, that is, downloaded.

As described above, the relatively high-power long-distance wireless interface 26, the relatively low-power short-distance wireless interface 27, and the weak radio wave wireless interface 30 are realized by one software receiver. By doing so, there is an advantage that it is possible to cope with an arbitrary communication system, and it is possible to easily cope with a need to change functions or improve performance by rewriting a software program for signal processing.

In the portable terminal 13, the terminal body 2
When adopting a configuration in which only a wired line is used without using a wireless line as a line between 1 and the audio input / output device,
Since the radio interface 30 for weak radio waves is not required, one software receiver includes two radio interfaces, a long-range radio interface 26 having a relatively large output and a short-range radio interface 27 having a relatively small output. What is necessary is just to make it have a function.

In the PDA shown in the example, if the long-distance wireless interface 26 and the short-distance wireless interface 27 are not used at the same time, the broadband receiving section 42, the D / A converter 43, The digital signal processing circuit 44 can be shared, and hardware can be shared by switching software.

Next, in the wireless communication system according to the first embodiment having the above configuration, that is, in the mobile communication system, a communication operation performed between the base station 11 and the relay station 12 and the portable terminal 13 will be described with reference to FIG. This will be described with reference to a flowchart. The communication operation in the mobile terminal 13 described below is executed under the control of a microcomputer built in the terminal main body 21.

In the standby state, first, it is determined whether or not the short-range wireless interface (IF) 27 is communicable, that is, whether or not it is located within the communicable area of the relay station 12 (step S11). Here, the position within the communicable area of the relay station 12 means that the relay station 12 is installed for each vehicle and gets on a train on which a wireless LAN environment is constructed, or that the relay station 12 is installed for each floor. Installed wireless L
For example, when the user enters a building where an AN environment is constructed.

Then, in the communicable area of the relay station 12,
That is, when entering the wireless LAN environment, the short-range wireless interface 27 receives a radio wave with a relatively small high-frequency output from the relay station 12. At this time, a radio wave of a relatively large high-frequency output transmitted from the base station 12 may arrive in the train or the building even though the power is reduced, and the radio wave for long distance 26 may receive the radio wave.

However, in step S11, it is determined only whether the short-range wireless interface 27 can communicate. That is, in the communicable area of the relay station 12, communication with the relay station 12 is prioritized over communication with the base station 11. If it is determined that the short-range wireless interface 27 can communicate, it is determined whether the mobile terminal 13 is used as a mobile phone (step S12).

The determination as to whether or not the portable telephone is used can be made based on a button operation by the user. If it is used as a mobile phone, it shifts to the telephone communication mode (step S13). Specific processing in the telephone communication mode will be described later. If it is not used as a mobile phone, it shifts to the data communication mode (step S14) because it is used as a PDA.

On the other hand, if it is determined in step S11 that the short-range wireless interface 27 cannot communicate, it is determined whether the long-range wireless interface 26 can communicate (step S15). . Whether or not the long-distance wireless interface 26 can communicate can be determined based on the intensity of the radio wave received by the long-distance wireless interface 26.

If it is determined that the long-distance wireless interface 26 cannot communicate, the display unit 2 of the terminal body 21
2 and / or display part 3 of voice stick 28
1 is displayed (step S16), and the process returns to the standby state.

On the other hand, when it is determined that the long-distance wireless interface 26 can communicate, it is determined whether the portable terminal 13 is used as a portable telephone (step S1).
7). If it is used as a mobile phone, the mode shifts to the phone communication mode (step S18). If it is not used as a mobile phone, it shifts to the data communication mode (step S19) because it is used as a PDA.

Next, the processing procedure in the telephone communication mode in step S13 will be described with reference to the flowchart in FIG.

When the telephone communication mode is entered, an empty channel of the weak radio wave radio interface 30 is searched (step S21), and it is determined whether or not there is an empty channel (step S22). Here, the search for an empty channel is performed in order to avoid interference when another person is talking using the voice stick 28 in the communicable area of the same relay station 12. is there. If there is no empty channel, since communication is impossible, a busy signal is returned to the base station 11 via the relay station 12 (step S23), and thereafter, the process returns to step S21.

On the other hand, if it is determined that there is an empty channel, a communication line with the voice stick 28 is set (step S24), and the weak radio wave radio interface 3 is set.
0, transmission and reception (communication) of call information such as voice and control information with the voice stick 28 (step S).
25). As described above, a series of processes in the telephone communication mode in step S13 ends.

As described above, in the wireless communication system according to the first embodiment, the base station 11 and the mobile terminal 1
The wireless LAN environment is constructed by interposing a relay station 12 between the relay station 3 and the mobile station 13, and a high-frequency power having a lower output is provided between the relay station 12 and the mobile terminal 13 than between the base station 11 and the mobile terminal 13. Communication in the wireless LAN environment, and the mobile terminal 13 gives priority to communication with the relay station 12 over communication with the base station 11, so that wireless L
In the AN environment, communication is always performed at a relatively low output high frequency, so that conversation and data transmission / reception can be performed without using a high output high frequency in a crowd such as in a train.

Thus, a wireless LAN environment such as a train, a station yard, or a department store is constructed, and in the wireless LAN environment, the mobile terminal 13 according to the present invention is used to send and receive e-mails using the mobile phone function. Or P
Even if various data is transmitted and received by the DA function, it does not adversely affect a person who has a pacemaker, so that the portable terminal 13 can be used even in a train. In addition, since the relatively low-output high frequency used in the wireless LAN environment can realize a higher data transmission speed than the communication with the base station 11, various data such as image data can be realized in the wireless LAN environment. High-speed transfer becomes possible.

The voice stick 2 shown in FIG.
By using a high-sensitivity microphone as the microphone used in the headset 8 or the headset 29, conversation in a low voice is also possible. Similarly, the mobile terminal 13 can be used as a mobile phone even in a train or the like. .

In the wireless communication system according to the present embodiment, for example, when a wireless LAN environment in a train is constructed, a case where the mobile terminal 13 is used as a mobile phone or a PDA in the environment has been described as an example. However, in addition, it is also possible to arrange a server in the train and provide various information such as music and news to each portable terminal from the server.

[Second Embodiment] FIG. 11 shows a second embodiment of the present invention.
1 is a conceptual diagram illustrating a configuration example of a wireless communication system according to an embodiment. The wireless communication system according to the present embodiment is configured as shown in FIG.
As is clear from FIG. 1, the mobile phone has a configuration including a base station 51 of a mobile phone, a relay station 52 arranged near a large screen (large video device) 54, and a mobile terminal 53 such as a mobile phone or a PDA. . Here, the large screen 54 is
In either case, it may be provided inside the building or outside the building, and in any case, it is connected to the center via a network and the video information supplied from the center is projected.

The relay station 52 establishes a wireless LAN environment around the front of the large screen 54, communicates with the base station 51 as in the case of the first embodiment, and locates in the wireless LAN environment. Between the mobile terminal 53 and the mobile terminal 53, the output of which is lower than the high frequency used for communication with the base station 51, for example, about several tens of mW, and can preferably perform high-speed data transmission as compared with a conventional mobile phone system. With
Communication is performed at a high frequency having a different frequency band from the high frequency used for communication with the base station 51.

The specific configuration of relay station 52 is the same as in the first embodiment, and a description thereof will not be repeated. The relay station 42 further has a function of connecting to a center via a network and distributing information such as music supplied from the center to the wireless LAN environment as in the case of the large screen 54.

The configuration of the portable terminal 53 is basically the same as that of the first embodiment. That is, the mobile terminal 53 includes the terminal main body 21 and a voice input / output device (the voice stick 28 and / or the headset 29) separate from the main body 21 as is apparent from FIG. At least a relatively large-output wireless interface for long distance 26 and a relatively small output for short-range wireless interface 27 (see FIG. 3) are built therein.

In the case of the first embodiment, the voice stick 28 and / or the headset 29 are provided as the audio input / output device. The headset 29 is considered essential as an input / output device.

In the wireless communication system according to the second embodiment having the above-described configuration, the mobile phone according to the present invention is provided in front of a large screen 55 connected to the center by a network, that is, in a high-speed wireless LAN environment constructed by the relay station 52. With the gathering of the people with the terminals 53, these people share the image projected on the large screen 55 as common information and also share the mobile terminal 53 according to personal interest.
Information can be obtained and exchanged through the Internet.

At this time, when acquiring and exchanging information, communication with the relay station 52 via the short-range wireless interface 27 of the portable terminal 53 (see FIG. 3) is performed at a relatively low-output high frequency. It is done fast. Also, among the people gathered in front of the large screen 55, there are those who want to use a mobile phone. In this case, since the relay station 52 can communicate with the external mobile phone base station 51 directly or via a network, the mobile terminal 53 can also communicate with the external mobile phone through the relay station 52. At this time, the first
As in the case of the embodiment, communication with the relay station 52 has priority over communication with the base station 51 in a wireless LAN environment.

As described above, in the wireless communication system according to the second embodiment, the wireless LAN environment is constructed by the relay station 52 in front of the large screen 54, and the , Base station 51
The mobile terminal 53 communicates with the mobile terminal 53 at a lower frequency than the mobile terminal 53, and in a wireless LAN environment, the mobile terminal 53 gives priority to communication with the relay station 52 over communication with the base station 51. With this configuration, communication is performed at a relatively low output high frequency in a wireless LAN environment, so that conversations and data transmission / reception can be performed without using a high output high frequency including a crowd at a concert hall or the like.

Further, by receiving the supply of information from the relay station 52 through the portable terminal 53, it is possible to share the video projected on the large screen 55 as common information, obtain information according to personal interests, Exchange can take place. In addition, since the frequency band of the relatively low-output high frequency used in the wireless LAN environment is wide, the base station 51
Since a higher data transmission speed can be realized as compared with communication with the wireless LAN, various data such as image data can be transferred at a high speed in a wireless LAN environment.

Further, when the large screen 54 is installed in an outdoor concert venue, information such as music is supplied to the audience only from the relay station 52 through the portable terminal 53, so that countermeasures against problems such as noise can be solved. Also. If necessary, a camera 55 may be provided near the large screen 54, and the image taken by the camera 55 may be displayed on the large screen 54.

In each of the above embodiments, different frequency bands are assigned to communications between the base station and the relay station and the portable terminal, and communications between the relay station and the portable terminal. Although the terminal side distinguishes between reception of a radio wave from the base station and reception of a radio wave from the relay station, the present invention is not limited to this, and the point is that reception of radio waves from the base station and reception from the relay station are important. Any configuration can be used as long as it can distinguish reception of radio waves.

More specifically, the same frequency band is assigned to communication between the base station and the relay station and the portable terminal, and to communication between the relay station and the portable terminal, respectively.
As shown in (2), even if the codes used for frequency spreading are selected so as not to interfere with each other (codes 1 and 2) and decoded with the code of the used channel, reception of radio waves from the base station and radio waves from Can be identified.

Further, in each of the above embodiments, the relatively low-output high frequency used for communication between the portable terminal and the relay station increases the communication between the portable terminal and the base station (equivalent to the conventional portable telephone system). ), The transmission speed is higher than the relatively high-output high-frequency wave. However, it goes without saying that the transmission speed may be the same.

[0069]

As described above, according to the present invention,
A wireless network environment is constructed by interposing a relay station between the base station and the mobile terminal. In this wireless network environment, communication is prioritized by low-output high-frequency with the relay station over high-output high-frequency communication with the base station. Communication, communication is always performed at low output and high frequency in a wireless network environment, so that conversations and data transmission and reception can be performed without using high output high frequency including people in trains. Become.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating a configuration example of a wireless communication system according to a first embodiment of the present invention.

FIG. 2 is a schematic perspective view showing a train on which a wireless LAN environment is constructed.

FIG. 3 is a front view illustrating an example of a configuration of a mobile terminal.

FIG. 4 is a diagram illustrating a relationship between a terminal body and a voice stick or a headset in the portable terminal.

FIG. 5 is a front view (A) and a side view (B) showing an example of the configuration of a voice stick.

FIG. 6 is a conceptual diagram illustrating an FDM method.

FIG. 7 is a conceptual diagram illustrating a TDM scheme.

FIG. 8 is a block diagram illustrating an example of a configuration of a software receiver.

FIG. 9 is a flowchart illustrating a procedure of a communication operation performed between the base station, the relay station, and the mobile terminal.

FIG. 10 is a flowchart showing a processing procedure in a telephone communication mode.

FIG. 11 is a conceptual diagram illustrating a configuration example of a wireless communication system according to a second embodiment of the present invention.

FIG. 12 is a conceptual diagram illustrating a CDM method.

[Explanation of symbols]

11, 51 ... base station, 12, 52 ... relay station, 13, 53
... portable terminal, 21 ... terminal body, 22, 32 ... display unit, 2
4: Pressure sensing part, 26: Wireless interface for long distance, 27
… Wireless interface for short distance, 28… Voice stick, 29… Headset, 30… Wireless interface for weak radio wave

Continued on the front page F term (reference) 5K023 AA07 AA08 EE01 EE03 EE17 5K027 AA11 AA12 CC08 KK03 5K067 AA03 AA06 BB04 EE02 EE06 EE10 EE61 FF23 GG06 GG08 GG11 HH05 5K072 AA05 BB03 BB03 BB03 BB03 BB03 BB03

Claims (19)

[Claims] 1. A relay station for communicating between a base station and the base station; and a relay station for communicating with the base station and communicating with the base station within a communicable area of the relay station. 1st used in
And a portable terminal that communicates with the relay station preferentially at a second high frequency that is lower than the high frequency and is distinguishable from the first high frequency. 2. The frequency band of the first high frequency wave and the second high frequency wave are different from each other.
A wireless communication system as described. 3. The system according to claim 1, wherein the first high frequency and the second high frequency have the same frequency band and are selected so that codes used for frequency spreading do not interfere with each other. Wireless communication system. 4. The wireless communication system according to claim 1, wherein the second high frequency has a higher transmission rate than the first high frequency. 5. A relay station for communicating with a base station, wherein the output power of the relay station is reduced to a second high frequency lower than the first high frequency used for communication with the base station and distinguishable from the first high frequency. A wireless network environment in which communication is performed by a portable terminal in the wireless network environment, wherein communication with the relay station is performed with priority over communication with the base station. Wireless communication method. 6. The frequency band of the first high frequency wave and the frequency band of the second high frequency wave are different from each other.
The wireless communication method as described. 7. The system according to claim 5, wherein the first high frequency and the second high frequency have the same frequency band and are selected so that codes used for frequency spreading do not interfere with each other. Wireless communication method. 8. The wireless communication method according to claim 5, wherein the second high frequency has a higher transmission rate than the first high frequency. 9. A portable terminal used in a wireless communication system including a base station and a relay station communicating with the base station, the first terminal being used for communicating with the base station. For communicating with the relay station at a second high frequency which is lower in output than a first high frequency used for communication with the base station and which can be distinguished from the first high frequency. A second wireless interface, and control means for giving priority to communication via the second wireless interface over communication via the first wireless interface within a communicable area of the relay station. A mobile terminal comprising: 10. The portable terminal according to claim 9, wherein the first high frequency and the second high frequency have different frequency bands. 11. The apparatus according to claim 9, wherein the first high frequency and the second high frequency have the same frequency band and are selected so that codes used for frequency spreading do not interfere with each other. Mobile terminal. 12. The system according to claim 9, wherein the second high frequency has a higher transmission rate than the first high frequency.
The mentioned mobile terminal. 13. The portable terminal according to claim 9, wherein said first and second wireless interfaces are constituted by one software receiver. 14. The portable terminal according to claim 9, wherein the portable terminal has a voice input / output device separate from a terminal main body containing the first and second wireless interfaces. 15. The portable terminal according to claim 14, wherein the voice input / output device is connected to the terminal main body via a wired line. 16. The portable terminal according to claim 14, wherein the voice input / output device is connected to the terminal body via a wireless line. 17. The terminal main body includes a third wireless interface for communicating with the audio input / output device at a third high frequency having a lower output than the second high frequency. 17. The mobile terminal according to claim 16, wherein 18. The mobile terminal according to claim 17, wherein said first, second and third wireless interfaces are constituted by one software receiver. 19. Both the terminal body and the voice input / output device have an input unit and a display unit, and input information from one of the input units is displayed on one of the display units, and the other is displayed on the other. The portable terminal according to claim 14, wherein the portable terminal is also displayed on a display unit.