JP2003264871A - Mobile communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile communication system in which efficient direct communication is surely realized between mobile station apparatus without increasing a load of a control station apparatus with high quality, a frequency utilization efficiency is enhanced and the service is improved by solving a problem of a conventional mobile communication system wherein the load of the control station apparatus is great for the direct communication between the mobile station apparatus placed at a short range. <P>SOLUTION: The mobile station apparatus 1a of a transmission source tries to perform direct communication with the mobile station apparatus 1b of a destination while stepwise increasing transmission power in response to an instruction from the control station apparatus 3, makes a channel assignment request for direct communication to the control station apparatus 3 when the direct communication is available, the control station apparatus 3 assigns a channel for the direct communication, and the mobile station apparatuses make direct communication by using the channel for direct communication assigned by the control station apparatus 3 with direct communication power determined by transmission power at which the direct communication has been made in the mobile communication system. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cellular system and the like.
For mobile communication systems, especially increase the load on control station equipment
Direct communication service between mobile station devices
The present invention relates to a mobile communication system that can be realized. [0002] A mobile communication system represented by a conventional cellular system is known.
Communication system (hereinafter referred to as cellular system)
This will be described with reference to FIG. FIG. 10 shows a conventional cellular phone.
FIG. 3 is an explanatory diagram for explaining an outline of a communication system of a stem. Conventional
In one cellular system, one radio base station device 2 is under jurisdiction.
Area is divided into units called cells, and multiple cells
Cell that provides a mobile communication system for a wide area
La System is the mainstream. [0003] Communication methods include mobile phones, PHS, and portable information.
Transfer of terminals (Personal Digital Assistants: PDA)
Regardless of the position or communication distance of the mobile station 1 ', the radio base station
Device 2, a control station device which is a higher-level device of wireless base station device 2
3 ′, the radio to which the mobile station device 1 of the communication partner belongs
Transmission from the base station apparatus 2 to the mobile station apparatus 1 'of the communication partner
Is taken. Keys used by the calling and called parties
For channels, it is based on the channel allocation algorithm.
The optimal channel is assigned dynamically,
As mentioned above, even if the communication partner is very
Even if you are in the vicinity, be sure to use the wireless base station device 2 and the control station
It was unified by the method via the device 3 '. [0004] However, further mobile phones and non-sound
As demand for voice communication data increases, cellular systems
Communication within the same cell or short-range communication between neighboring cells
Considering the increase, conventional cellular system technology
Operation is very inefficient from the viewpoint of frequency utilization efficiency.
There is a need for a new communication method. [0005] With regard to short-distance communication demand, subscribers (fixed
Constant) The communication frequency is the communication distance
Is inversely proportional to the number of lines,
The demand for short-distance calls will increase with the increase in
Can be considered enough. On the other hand, non-voice communication data demand
Also, mobile stations such as mobile phones
Network competition games, etc. between neighboring mobile phones
It could be done. In consideration of these, a mobile station apparatus for performing communication
When the distance between 1 'is short, without going through a network
Need for technology for direct communication (call) between mobile station devices 1 '
For example, Japanese Unexamined Patent Application Publication No.
2001-238264 "Mobile communication system and its
Direct call method used by the applicant ”(Applicant: NEC Engineer
Alling Co., inventor: proposed by Shinji Yamasumi
I have. In this conventional technology, a radio base station management station makes a direct call.
Determine the position of the desired mobile radio station and the mobile radio station of the communication partner.
Search and estimate distance, estimate electric field strength and make direct calls
If it is determined that it is possible, both mobile radio stations
Direct communication with notification of designation, radio frequency, connection code, etc.
Mobile communication system for performing communication in mode
This is a direct call method used for
To reduce the workload and reduce the burden of charging users.
You can do it. [0007] However, Japanese Unexamined Patent Application Publication No.
In the mobile communication system of 001-238264,
The line base station management station estimates the distance between terminals and estimates the electric field strength.
To determine whether it is possible to make a call directly.
Configurations for field strength estimation increase, and direct call is desired
If the number of mobile radio stations
There was a problem that it increased. Further, Japanese Patent Application Laid-Open No. 2001-238264 discloses
In mobile communication systems, the results of distance estimation and field strength estimation
To determine whether communication is possible directly from the
Therefore, a situation different from the estimation result may occur, and
Service degradation due to poor communication quality, etc.
There was a problem that was feared. The present invention has been made in view of the above circumstances.
Direct communication service between mobile station devices located at short distances.
Service without increasing the load on the control station equipment.
High quality with high reliability, and
To improve spectrum utilization efficiency and service.
With the aim of providing a mobile communication system that can
I do. Means for Solving the Problems The problems of the above conventional example are solved.
The present invention for determining, in a mobile communication system,
There is no communication between the mobile station device and the mobile station device in the cell under its jurisdiction.
Wireless base station device for performing line communication and multiple wireless base station devices
And a control station device that controls connection of the mobile station device.
A mobile communication system having
When receiving a call request from the source mobile station device,
If the mobile station device is in a cell under its jurisdiction,
Instructions to attempt direct communication between the
Output to mobile station, for direct communication from source mobile station
Channel request for direct communication,
Mobile station device that is the control station device to which the
However, according to the instruction from the control station device,
Try direct communication with the destination mobile station while increasing
If direct communication is possible,
Requests channel assignment for communication and enables direct communication
Direct communication power determined using the transmission power when
Channel for direct communication assigned by control station equipment by force
Because it is a mobile station device that communicates directly using
Whether direct communication between mobile station devices located in a short distance
Confirmation by direct transmission and reception between mobile station devices
To increase the load on the control station equipment by direct communication service
, And can be realized efficiently and with high quality. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings.
This will be described with reference to FIG. Note that the functions described below are implemented.
What means is a means that can realize the function
May be simple circuits or devices,
All can be realized by software. Change
Alternatively, the function realizing means may be realized by a plurality of circuits.
In other words, multiple function realizing means may be realized by a single circuit.
No. The mobile communication system according to the present invention provides
Station device accepts a call request from the originating mobile station device
Sometimes, the destination mobile station device is in a cell under its jurisdiction
Attempt direct communication between the source and destination mobile station devices
Is output to each mobile station, and the source mobile station
However, according to the instruction from the control station device,
Try direct communication with the destination mobile station while increasing
If direct communication is possible,
Makes a communication channel assignment request, and the control station
Channels for direct communication are allocated, and mobile
Determined using the transmission power when communication was possible
Direct communication assigned by the control station equipment with direct communication power
Because it communicates directly using the dedicated channel
Move the possibility of direct communication between mobile station devices located far away
By confirming by direct transmission and reception between station devices,
To increase the load on the control station equipment for direct communication services
And can be realized efficiently, with high quality. First, a mobile communication system according to the present invention will be described.
The device configuration and the schematic operation will be described with reference to FIG. Figure
1 is a device configuration diagram of a mobile communication system according to the present invention.
is there. Note that the same configuration as in FIG.
The description is given with the same reference numeral. The mobile communication system according to the present invention
As in the prior art, the stem is connected to the mobile station device 1 and the air jurisdiction.
The mobile station device 1 in the rear (cell) and the radio channel
Wireless base station device which is a relay device for transmitting and receiving data
(Base Transceiver Station: BTS) 2 and multiple
Host device connected to the wireless base station device 2 via a dedicated wired transmission path
From the control station device 3 that controls network connection with the device
It is configured. The mobile communication system according to the present invention comprises:
A mobile station device 1 which is a conventional communication method is a radio base station device 2
And a method of communicating with each other via the control station device 3.
In consideration of the distance to the communication partner,
If the distance is shorter than the distance in the control, the control station device 3 determines
The mobile station devices 1 communicate with each other using the
The communication is performed directly without going through a network. [0015] In particular, direct communication is a feature of the present invention.
The first step is to determine whether or not
To determine whether there is a possibility of a direct call in the control station device 3.
Judgment and if there is no possibility, use the same communication method as before.
Communication, and if there is a possibility, as a second step,
Direct communication between both mobile station devices 1 trying to communicate
To determine if it is possible and communicate directly if possible.
If it is not possible, perform communication using the conventional communication method.
It has become. Here, the control station apparatus 3 in the first step
To determine the possibility of direct call
Cell to which the two mobile station devices 1 belong (the serving cell).
) Are both connected to the control station device 3.
Direct call when the cell is under the control of the wireless base station device 2
Take the method to judge that there is a possibility. Specifically, for example, as shown in FIG.
When a call request is made from a mobile station device 1a,
A control station device that has accepted a call request via the local station device 2a
3 searches for the location registration information, and the mobile station as the communication partner
Radio base station device in which device 1 is connected to control station device 3
2 under the jurisdiction of the control station device 3.
Check whether or not. That is, the control station device 3 communicates with the communication partner (destination).
The cell to which the mobile station device 1 (call destination) belongs is, for example, a mobile station.
Same as cell A to which mobile station apparatus 1a belongs, as in apparatus 1b.
Or the mobile station device 1c, for example.
In the cell A to which the mobile station device 1a belongs and the neighboring cell B
In some cases, the jurisdiction of one control station device 3
It is determined that there is a possibility of a direct call,
In order to proceed to the steps, for both mobile station devices 1,
Send instructions to try a direct call. Further, both mobile station devices 1 in the second step
The method of determining whether direct communication is possible by
Transmission power smaller than the transmission power used for transmission with the device 2
Calling request for direct communication (direct communication calling request) on the calling side
From the mobile station device 1a to the other party, and if there is a response,
This is a method for determining that direct communication is possible. Then, the two mobile station devices 1 use each other.
If it is determined that direct calls are possible
First, the control station device 3 determines the transmission power and channel allocation for direct communication.
Is notified to both mobile station devices 1 and both mobile station devices are notified.
Direct call using the relevant channel between the devices 1 (open in the figure
Arrow). If the exchange between the two mobile station devices 1 is
Therefore, if it is confirmed that direct calling is not possible,
Your station device 3 is used for a normal call through the radio base station device 2.
Channel allocation is determined and transmitted to both mobile station devices 1.
Communication between both mobile station devices 1 using the channel.
To make a telephone call (black arrow in the figure)
Has become. Next, a mobile communication system according to the present invention will be described.
The following describes each device. First, the mobile station device 1
An outline of the configuration will be described with reference to FIG. FIG.
1 is a block diagram showing the internal configuration of the mobile station device 1 of the present invention.
It is. The mobile station device 1 according to the present invention, as shown in FIG.
An antenna 18 for transmitting and receiving wireless signals;
Transmission / reception unit that performs bidirectional conversion with the
Is the TRX section) 11, error correction, framing, and data conversion.
Baseband processing that performs baseband signal processing such as demodulation
Processing unit 12, an audio processing unit 13 for processing an audio signal,
A display unit 14 for displaying various data;
Which input unit 15 is used for various inputs,
Storage unit 16 for storing data such as
Interface section 17 for performing protocol conversion, etc., and each section
And a central processing unit 10 for controlling
You. The mobile station device 1 of the present invention is
Communication via the wireless base station device 2 by a similar communication method
In addition to the operation of performing
According to the instruction from the device 3, direct communication is attempted, and if possible,
Perform communication (call) with another mobile station device 1 by close communication
Things. It should be noted that the direct communication control which is a characteristic part of the present invention is performed.
Control is performed until communication (call) performed by the central processing unit 11.
This is realized by a control program that performs connection control. Ma
In addition, wireless channels for direct communication
As in the case of the communication method of
By the control station device 3 that communicates with the wireless channel
Medium control method. Specifically, the mobile station device 1 of the present invention
As a channel for wireless communication with a normal wireless base station device 2.
Channel (usually called a communication standby channel)
And test whether direct call, which is a feature of the present invention, is possible.
Can accept direct call request
Channel call request channel and direct communication channel assignment
Standby channel for receiving application information (direct communication
Standby channel) and assigned by the control station device 3.
Channel for direct communication (direct communication channel)
have. Then, the conventional location registration is performed.
Therefore, the outgoing (calling) side control is as usual
After sending the request, test whether direct communication is possible with the call request response.
If there is an instruction to watch (direct communication try instruction),
Processing to determine whether direct communication is possible (direct communication determination processing)
Do). The direct communication determination process is a process of determining
Directly with a transmission power smaller than the transmission power used for transmission with
Determine if there is a communication partner within the communication range
This is the process that Specifically, a direct communication call request is
At time intervals, transmit power is increased step by step (transmission
From the mobile station device 1 of the communication partner receiving the
This is a process for confirming a direct communication call response. Here, the time for transmitting the direct communication call request
Increase the interval, the initial setting of the transmission power and the transmission power
The amount of increase and the upper limit are assumed to be preset.
I do. The sequence number is sent every time a direct communication call request is sent.
No. is set for direct communication call request and response.
And the sequence number.
Direct communication call response from the mobile station device 1 of the communication partner at the time of
Check if there was. And the preset upper limit
Increase the transmission power up to send a direct communication call request
Also, if there is no response from the mobile station device 1 of the communication partner,
Judgment that there is no communication partner in the area where direct communication is possible
You. Here, the upper limit value of the transmission power is the cell
If it is located at the center of the cell from the mobile station device 1 at the end
The signal transmitted to the assumed base station 2 is correctly received.
There is a method of setting a fixed value using the smallest possible power value. This
This is better than direct communication over the distance between terminals that is greater than the cell radius.
Communicates with the wireless base station device 2 in the center of the cell
This is because the transmission power can be reduced by performing. On this
With the mobile station device 1 of the communication partner with the transmission power before reaching the limit value.
If you can communicate directly, the transmission power will be higher than in the conventional method.
It can be reduced. The upper limit is set to the above-described cell.
In addition to the transmit power that can be communicated over the radius,
A value based on the transmission power to the base station apparatus 2 is also used.
There is also a possible method. For example, the last outgoing call request
The upper limit value is twice the transmission power at the time of transmission. This allows
The wireless base station device 2 is closer than the communication partner mobile station device 1
If there is a location, a direct communication call request
Not received by the mobile station device 1 and no direct communication call response is returned
Will be. Then, direct communication with the mobile station device 1 of the communication partner is performed.
If it is determined that communication is possible,
The direct communication channel containing the sequence number for which the
The control station device 3 transmits a
Direct communication channel information and direct communication
Direct communication including transmission power (called direct communication power) at the time of communication
Receives a communication channel assignment response and indicates that the call is direct.
Displays the specified direct communication channel
Direct communication (call) using the direct communication power
is there. Further, the mobile station apparatus 1 of the present invention
The call side control is performed in accordance with an instruction from the control station device 3.
The normal communication standby channel and the direct communication call request channel
And direct communication on the direct communication call request channel
When a call request is received, a direct communication call response is returned and control is performed.
Receiving a communication channel assignment response directly from the station device 3
And the calling side moves with the specified channel and direct communication power
It performs direct communication with the station device 1. Further, the mobile station apparatus 1 of the present invention
Set the communication standby channel directly from device 3 to the normal communication standby channel
When instructed to return to or when the call ends directly
Returns to the normal communication standby channel and returns to the normal standby
State. Call origination processing in the mobile station apparatus 1 of the present invention
A specific example of the flow will be described with reference to FIG. FIG.
Is a flowchart of a calling process in the mobile station device 1 of the present invention.
It is a chart. In the mobile station device 1 of the present invention, when making a call
First, a call request is transmitted to the radio base station apparatus 2.
(100), receives a call request response from the wireless base station device 2
(102), the received call request response
It is determined whether the instruction is an instruction (104), and a direct communication try instruction is issued.
If not (No), it means that the communication partner is not near
The communication control via the conventional network
Normal communication is performed (106). On the other hand, in process 104, the received call
When the request response is a direct communication try instruction (Yes)
The initial sequence number as a direct communication determination process.
(110), and set the transmission power to an initial value (11).
2) Send a direct communication call request (114) and perform direct communication
It is determined whether a call response has been received (116).
If not (No), it is determined whether the transmission power has reached the upper limit.
(120), if not reached (No),
The transmission number is incremented by one (122).
The number of steps is increased (124), and the process returns to step 114 to reduce the transmission power.
In the increased state, transmission and reception of direct communication call requests
Return. In processing 120, the upper limit of the transmission power
If the value has been reached (Yes), direct communication is not possible
Therefore, communication via the conventional network
Returning to the communication control, normal communication is performed (140). Specifically
Sends a standby channel change request from the wireless base station apparatus 2
Receive, shift to normal standby channel, normal standby
Channel from the wireless base station device 2 by using the connection channel
Information notification and receive normal
Performs communication via a network. On the other hand, in process 116, a direct communication call is made.
If a response is received (Yes), direct communication is possible.
That's why I switched to a direct communication standby channel.
(130), the direct communication channel assignment request is sent to the radio base station
(132) and sends the direct communication channel assignment response
Receiving (134), displaying that direct communication is in progress
From the direct communication channel assignment response
Switch to direct communication channel according to communication channel information
The direct communication included in the direct communication channel assignment response
Direct communication is performed by power (136).
When performing direct communication, it indicates that direct communication is in progress.
Displayed on the display. Next, the internal configuration of the radio base station apparatus 2 will be described.
This will be described with reference to FIG. FIG. 4 shows a wireless base according to the present invention.
FIG. 3 is a block diagram illustrating an internal configuration of the station device 2. Of the present invention
The radio base station apparatus 2 transmits a radio signal as shown in FIG.
An antenna 27 for receiving, a radio signal to be transmitted and reception
Amplifying section (AMP section in the figure) for amplifying the converted radio signal 26
Performs bidirectional conversion between radio signals and baseband signals.
Transmitting / receiving unit (TRX unit in the figure) 25, error correction, frame
And baseband signal processing such as data modulation and demodulation.
Connection between the baseband processing unit 24 and the control station 3
A wired transmission path 21 for performing connection, a baseband processing unit 24,
Performs wireless-ATM data conversion with the wired transmission path 21.
ATM switch (ATM-SW in the figure) 28 and call processing
A call processing control unit 22 for controlling the
A maintenance monitoring control unit 23 is provided. The radio base station apparatus 2 of the present invention is
A control station that is exactly the same as the base station device 2 and is a higher-level device.
It is connected to the device 3 by a dedicated wired line and has jurisdiction.
Performs wireless communication with the mobile station device 1 in the area (cell).
Operates as a relay station between the mobile station apparatus 1 and the control station apparatus 3.
Is what you do. Next, the internal configuration of the control station device 3 will be described.
This will be described with reference to FIG. FIG. 5 shows the control station device 3 of the present invention.
FIG. 2 is a block diagram showing an internal configuration of the device. Control station of the present invention
The device 3 includes a main control unit 31, a signal termination card unit 32,
Diversity handover processing and wireless layer MAC layer multiplexing
Diversity handover trunk car that performs separation processing
/ Mac demultiplexing card (DHT / M-MU in the figure)
X) A card that synchronizes the unit 33 with the radio frame.
Clock synchronizer 34, and the connection between each card and a wired line.
A transmission line interface unit 35 for
A wired (ATM) line interface with the base station 2
Each of the wired transmission path 36 and the ATM cells from the wireless base station 2
ATM- which performs header conversion etc. for branching to a card
And a SW unit 37. Then, the control station device 3 of the present invention
It is connected to the base station device 2 via a dedicated wired transmission line,
Signals from the radio base station apparatus 2 that have been
Distribution processing control to the line base station apparatus 2, outgoing / incoming connection control, termination
Control operation of the present invention
As a characteristic part of the device 3, in connection control of outgoing and incoming calls,
In the case of connection between mobile station devices 1 located in a cell under its control
Is a direct communication promotion process that promotes direct communication.
is there. In addition, connection control of outgoing / incoming, which is a characteristic part of the present invention.
Performs connection control for outgoing / incoming calls executed by the main control unit 31
This is realized by a control program. More specifically, the direct communication promotion processing is an arbitrary transfer.
In response to a calling (calling) request from the mobile station device 1, a communication partner
Is a radio base station connected to the same control station device 3 as the originating side
If it is in the cell under the jurisdiction of the device 2 (that is, the same location registration
Possibility of direct calls in the rear or paging area)
Is judged to be possible, and whether direct communication is possible
And, if possible, direct communication.
You. Here, the connection in the control station device 3 of the present invention will be described.
A specific example of the flow of the connection control process will be described with reference to FIG.
I do. FIG. 6 shows connection control in the control station device 3 of the present invention.
It is a flowchart figure of a process. Control station device 3 of the present invention
First, the connection control process is performed via the wireless base station device 2
Upon receiving a call request from the originating mobile station device 1a (20)
0), the mobile station device of the communication partner (called side) based on the location registration information
1b is confirmed (202), and the mobile station device 1 on the receiving side is checked.
It is determined whether or not b is under the jurisdiction (204).
In the case of (No), both mobile station apparatuses 1a and 1b are close to each other.
There is no possibility of direct calls,
Normal communication connection by connection control via the network of
Processing is performed (210). On the other hand, in process 204, the movement of the receiving side
If the station device 1b is under the jurisdiction (Yes), the receiving side
Communication with the standby channel directly to the mobile station device 1b
Change standby channel to switch to standby channel
Send a change request (220), and reply to a standby channel change
(222), and directly communicates with the originating mobile station device 1a.
Sends a call request response of the communication try instruction (224), and
The process starts (226). Then, a direct message from the originating mobile station device 1a is sent.
It is determined whether a connection channel assignment request has been received (22).
8) If received (Yes), direct communication is possible
Therefore, it is included in the direct communication channel assignment request.
The transmission power is associated with the sequence number and the direct communication channel is
(230), and determines the determined transmission power.
Direct communication channel assignment including direct communication channel information
The response is transmitted to both the mobile station device 1a and the mobile station device 1b.
(232), and terminates the connection control process.
You. The control station device 3 has a sequence number
Is provided in advance with a table that can determine the transmission power from
Sequence number included in direct communication channel assignment request
The communication power and the assigned channel directly based on the
It has become so. On the other hand, in process 228, the direct communication channel
If the channel assignment request is not received (No), the timer
Determine if the timeout has been reached after reaching the preset time.
(240), and if the timeout has not occurred (N
In o), it is necessary to return to step 228 and directly assign a communication channel.
Wait for the request to be received. Note that the time-out period is
The transmission interval for the direct communication call request and the transmission power
The number of transmissions until the upper limit is reached by gradually increasing the force
Timer value determined from a number. In process 240, a timeout occurs.
If yes (Yes), direct communication is not possible
Therefore, both the mobile station device 1a and the mobile station device 1b
Return standby channel to normal standby channel
A standby channel change request to be transmitted (242);
Perform normal communication via the conventional network
Normal connection control is performed (244). Next, in the mobile communication system of the present invention,
An example of the operation at the start of communication will be described with reference to FIGS.
I will tell. FIG. 7 shows a mobile communication system according to the present invention.
Sequence indicating the connection control sequence when direct communication is possible
FIG. 8 is a diagram showing a mobile communication system according to the present invention.
Sequence indicating the connection control sequence when direct communication is not possible.
FIG. The communication between the mobile station device 1 and the control station device 3 is performed.
The communication is basically performed via the wireless base station device 2,
It is omitted in the description. In the mobile communication system of the present invention,
Of the mobile station device (mobile phone in the figure) 1 owned by the user
During the standby state after the power is turned on, as shown in FIG.
Broadcast information transmitted from the wireless base station device 2
The mobile station apparatuses 1a and 1b receive the broadcast information channel and
In the state where the presence notification is being transmitted to the base station device 2
The location notification is transmitted from the wireless base station apparatus 2 to the control station apparatus 3.
The mobile station devices 1a, 1
The position of b is the identifier of the wireless base station device 2 of the serving cell.
It is managed as registration information. Then, the transmission from the mobile station device 1a of the transmission source is performed.
The call request is controlled by a dedicated wired line via the wireless base station device 2.
It is transmitted to the control station apparatus 3 and the control station apparatus 3
Location registration information of the mobile station device 1b
If the device 1b is in the cell under its jurisdiction,
Incoming calls to promote direct communication as
A standby channel change request is transmitted to the previous mobile station device 1b.
In the mobile station device 1b, the standby channel is
Direct communication call that can accept a close communication call request
Changed to the request channel and the standby channel change response
It is returned to the control station device 3 and further transmitted from the mobile station device 1a.
Sends a call request response with a try instruction to attempt direct communication.
The timer is started in the control station device 3.
You. In response to a call request of a try instruction to attempt direct communication
When the answer is received by the mobile station device 1a,
The sequence number is incremented as a direct communication judgment process.
While increasing the transmit power step by step
A close communication call request is transmitted. At this time, the destination mobile station
When the direct communication call request is received by the device 1b,
The call communication response is returned, and the mobile station device 1a communicates directly.
Sends a direct communication call request when a call response is received
Is stopped, and both mobile station devices 1a and 1b control station devices are stopped.
Communication standby so that the response from 3 can be received.
Direct communication channel containing sequence numbers
The assignment request is transmitted to the control station device 3. Control receiving direct communication channel assignment request
In the station device 3, the system included in the direct communication channel assignment request is
The transmission power is associated with the
Channel allocation is determined, and transmission power and direct communication channels are determined.
Direct communication channel assignment response including channel assignment information
Is transmitted to both the mobile station device 1a and the mobile station device 1b,
In both the mobile station device 1a and the mobile station device 1b,
Communication is displayed, and the assigned direct communication
Switch to the user information (voice / packet data).
Is directly communicated. On the other hand, although direct communication was promoted and tried,
FIG. 8 shows a connection control sequence when the connection is possible.
As described above, the mobile station device 1a of the transmission source changes from the standby state.
A call request is transmitted and the control station device 3
It is confirmed that the device 1 is in the cell under its jurisdiction and the source
Of a try instruction to attempt direct communication to the mobile station device 1a
The request response is sent, the timer is started, and the mobile station
Transmission of direct communication call request from device 1a to mobile station device 1b
Is the same up to the point where Here, although the transmission power is increased step by step,
Sends a direct communication call request from the originating mobile station device 1a
Is not received when the mobile station device 1b is far away,
Since the direct communication call response is not returned, the mobile station device 1a
In this case, the transmission power reaches the upper limit and direct communication is not possible.
Transfer to the communication standby channel
You. At this time, in the control station device 3, the timer is started.
Direct communication channel within specified time from start
Timed out because the allocation request could not be received and
Communication is determined to be impossible, and the standby channel change request
It is transmitted to both the mobile station devices 1a and 1b,
The standby channel is the normal standby channel in the mobile station device 1.
The control station device 3 changes the channel for normal communication.
Is assigned and notified.
User information via the line base station apparatus 2 and the control station apparatus 3
(Voice / packet data) is to be communicated
You. In the above description, the transmission power for direct communication
(Direct communication power) for direct communication between mobile station devices 1
Sending when it is possible to exchange a call request / response
Direct communication power is determined based on communication power
However, when the mobile station device 1 performs direct communication,
Monitors the received electric field strength of the transmitted signal, etc.
If the degree becomes strong, request the other side to reduce the transmission power.
And the mobile station device 1 that has received the
It may be reduced by one step. On the other hand,
If the field strength becomes weaker, the transmission power increases to the other party.
The mobile station device 1 that has transmitted the request and received the
The force may be increased by one step. Also, transmission power control according to the reception electric field strength
As another method, the mobile station device 1 performs direct communication.
Between the time slots of the wireless base station device 2
Between the broadcast information and the location information
The mobile station device 1 and the radio base station device
2 can transmit and receive control information for power control
To maintain the state. Then, direct communication is performed by the mobile station apparatus 1a as the transmission source.
Monitors the received field strength during a call, and checks for changes in the received field strength.
Sequence numbers and manage them periodically or
When the received electric field strength changes, the mobile station device 1a of the transmission source
Is updated to the control station device 3 through the wireless base station device 2
Request for direct communication channel assignment including the sequence number
To the sequence number updated by the control station device 3.
Determine the corresponding direct communication power and set the
The specified direct communication channel assignment response is sent to both mobile stations.
Transmit to the devices 1a and 1b, and both mobile station devices 1a and 1b
May be used to directly change the communication power. When performing the above control, the direct communication channel
The transmission of the file allocation request also matches the time slot of the direct communication.
It will be done using time. Also, all mobile station devices
1 is a report from the radio base station apparatus 2 between time slots.
The wireless base station apparatus 2 directly receives the knowledge information.
Broadcast information is sent to the mobile station device 1 during communication for a plurality of times.
Must be able to transmit in the slot
No. Next, in the mobile communication system of the present invention,
Call control system at the end of communication when direct communication is performed.
The sequence will be described with reference to FIG. FIG.
Termination at the end of direct communication in Ming mobile communication system
It is a sequence diagram showing a control sequence. Mobile station equipment
In 1a and 1b, the mobile station device 1 which is a communication partner of each other
A direct communication termination request is sent to the
Is returned, and the mobile station device 1 terminates the call.
Thereafter, both the mobile station devices 1a and 1b
Is transmitted directly to the control station 3 and transmitted to the control station 3.
It is. The control station device 3 receives the direct communication completion notification.
, A direct communication completion response is sent via the wireless base station device 2.
Transmitted to each mobile station device 1a, 1b to establish a call end.
However, in each of the mobile station devices 1a and 1b, a standby channel
Returns to the always-on standby channel and transitions to the standby state.
You. At this time, the mobile station apparatus 1
The direct communication completion notification sent includes the direct communication time and
By including the data amount, the control station device 3
The billing calculation can also be performed based on the information. According to the mobile communication system of the present invention,
If the correspondent is in a cell under the control of the same control station device 3,
In this case, considering the distance to the communication partner, the radio base station apparatus 2
If the distance is shorter than the distance to
The mobile station devices 1 use
Via the network of the line base station apparatus 2 and the control station apparatus 3
Demand is expected to increase in the future because direct communication is performed without
Traditional short-range communication and non-voice data communication
In addition to the communication method via the network,
By adding communication, limited frequency
To make effective use of several resources and improve spectral efficiency
There is an effect that can be. In addition, a new device is required for a telecommunications carrier.
Direct calls without the need for additional calls
When the number of opportunities for performing is increased, the radio base station apparatus 2 or the control station
Reduce load on device 3 and efficiently allocate wireless channels
Is cheaper than conventional communication methods
It is also possible to provide services at reasonable rates.
You. In the mobile communication system of the present invention,
The mobile station device 1 determines whether or not direct communication is actually possible.
Japanese Patent Application Laid-Open No.
No. 01-238264, the mobile station is controlled by the control station device 3.
Is it possible based on the estimation result of the distance between the devices 1 and the electric field strength
Compared to judging whether or not there are obstacles and weather
Whether it is possible to include the transmission path conditions (communication conditions) that change from time to time
Mobile communication system.
Has the effect of improving the reliability as well. Also, whether direct communication is actually possible or not
Is confirmed by exchanging data between the mobile station devices 1.
Therefore, a set of mobile station devices 1 that have a possibility of direct communication
Even if it increases, as in JP-A-2001-238264,
The load on the control station device 3 does not increase, and the configuration of the device is
Without the need to expand
This has the effect of maintaining the stability in all cases. Further, according to the mobile communication system of the present invention,
Mobile station equipment to determine whether direct communication is actually
Send when confirming by exchanging data between 1
Increasing the power step by step and determining that transmission and reception are possible
Since subsequent direct communication is performed with the minimum transmission power
In comparison with the conventional method of performing wireless communication with the wireless base station device 2 in practice
Can also reduce the transmission power, and the mobile station device 1
This has the effect of reducing power consumption. Also, the received electric field strength is monitored during the direct communication process.
And adjust the transmission power according to the strength of the received electric field.
If control is performed to raise or lower the floor, transmission power can be further increased.
Can be changed efficiently and reduced as a whole,
There is an effect that power consumption in the mobile station device 1 can be reduced. Also, it depends on the ratio of direct communication.
However, direct communication reduces mobile phone transmission power.
This can reduce interference waves, and
Rate and increase user capacity per cell
To improve services as a mobile communication system.
There is an effect that can be. Also, for example, a station close to the radio base station apparatus 2
Mobile station device 1a and mobile station device 1b
When the mobile station device 1c is located far from the station device 2,
Direct communication between the mobile station device 1a and the mobile station device 1c.
When performing, the mobile station device 1a moves downward with respect to the mobile station device 1c.
When transmission is performed using the bandwidth,
To prevent reception from line base station device 2 from being disturbed
Can be. Further, according to the mobile communication system of the present invention,
For example, the control for determining whether direct communication is possible
Although performed between the devices 1, the direct communication channel and the power
Centralized control of decision, notification and end-of-call confirmation by the control station device 3
Therefore, power control harmonized with the conventional method becomes possible
In addition, it is possible for the control station device 3 to directly manage the communication time and the like.
Can be charged for direct communication.
There is an effect that the service can be commercialized. Further, whether the user uses the mobile station device 1
In short, the mobile station device 1 (mobile phone
There is no change in the operating procedure of
Direct communication is automatically performed, which is no different from conventional calling methods.
Service as an easy-to-use service.
There is an effect that it is easy to insert. Further, according to the mobile communication system of the present invention,
For example, it is possible to determine whether direct communication between mobile station devices 1 is possible.
Mobile station device 1 on the receiving side
If the mobile station device does not have the function of
No response is returned to the direct communication call request from the caller
However, in the mobile station device 1 on the transmission side, the transmission power reaches the upper limit value.
And the control station device 3 times out and directly
It is determined that communication is not possible, and the normal communication connection
Without any special equipment or processing.
Also supports the conventional mobile station device and the direct communication function of the present invention.
Environment that can be used together with a mobile station device 1
Therefore, temporary service as a mobile communication system
New services can be introduced without causing confusion
There is fruit. According to the present invention, the control station apparatus is capable of transmitting
When a call request is received from another mobile station device, the destination
If the mobile station is in a cell under its jurisdiction,
Instruct each mobile station to try direct communication between the
Output to the device, and the originating mobile station device
Follow the instructions in
Attempt direct communication with the previous mobile station
If there is, the control station device allocates a channel for direct communication.
Request, and the control station device establishes a direct communication channel.
Assignment, when direct communication between mobile station devices is possible
The control station uses the direct communication power determined using the
Using the channel for direct communication allocated from the device
Since it is a mobile communication system that performs direct communication,
Direct communication service between mobile station devices located at a distance
Efficiently without increasing the load on the control station device,
High quality and reliable realization, and the overall mobile communication system
To improve frequency utilization efficiency and service
There is an effect that can be.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a device configuration diagram of a mobile communication system according to the present invention. FIG. 2 is a block diagram showing an internal configuration of a mobile station device according to the present invention. FIG. 3 is a flowchart of a calling process in the mobile station device of the present invention. FIG. 4 is a block diagram illustrating an internal configuration of a wireless base station device according to the present invention. FIG. 5 is a block diagram showing an internal configuration of a control station device of the present invention. FIG. 6 is a flowchart of a connection control process in the control station device of the present invention. FIG. 7 is a sequence diagram showing a connection control sequence when direct communication is possible in the mobile communication system of the present invention. FIG. 8 is a sequence diagram showing a connection control sequence when direct communication is not possible in the mobile communication system of the present invention. FIG. 9 is a sequence diagram showing a call termination control sequence at the end of direct communication in the mobile communication system of the present invention. FIG. 10 is an explanatory diagram illustrating an outline of a communication system of a conventional cellular system. [Explanation of Reference Codes] 1, 1 ': mobile station apparatus, 2: radio base station apparatus, 3,
3 ': control station device, 10: central processing unit, 11: transmitting / receiving unit, 12: baseband processing unit, 13: voice processing unit, 14: display unit, 15: input unit, 16: storage unit, 17: interface unit , 18 ... antenna,
DESCRIPTION OF SYMBOLS 21 ... Wire transmission line 22 ... Call processing control part 23 ... Maintenance monitoring control part 24 ... Baseband processing part 25 ...
Transmitter / receiver unit, 26 amplifying unit, 27 antenna, 28 ...
ATM switch, 31: Main control unit, 32: Signal termination card unit, 33: Diversity handover trunk car / Mac demultiplexing card, 34: Clock synchronization unit, 35: Transmission line interface unit, 36: Wire transmission line, 37: ATM -SW section

Claims (1)

Claims: 1. A mobile station device, a radio base station device that performs radio communication with the mobile station device in a cell under its jurisdiction, and a plurality of the radio base station devices, A mobile communication system having a control station device that performs connection control of the mobile station device, wherein the control station device receives a call request from a source mobile station device, When in the cell under its jurisdiction, outputs an instruction to attempt direct communication between the source and destination mobile station devices to each of the mobile station devices, and a channel for direct communication from the source mobile station device. When there is an assignment request, the control station device assigns a channel for direct communication, wherein the source mobile station device moves the destination while gradually increasing transmission power according to an instruction from the control station device. Try direct communication with Only, when direct communication was possible, a channel assignment request for direct communication was made to the control station apparatus, and the direct communication power determined using the transmission power when direct communication was possible was used. A mobile communication system, which is a mobile station device that performs direct communication using a direct communication channel allocated by a control station device.