JP4186060B2 - Wireless LAN system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention uses a wireless LAN (Local Area Network).UseThe present invention relates to a wireless LAN system that transmits information including streaming information such as audio information and video information.
[0002]
[Prior art]
Wireless LAN systems that transmit information including streaming information such as audio information and video information between a server and a plurality of terminals using a wireless LAN are provided. Here, the streaming information is information that is reproduced at the same time while reading the information, and has so-called real-time characteristics.
[0003]
In this type of wireless LAN system, it is important to maintain the quality of service (QoS) of streaming information, and conventionally, measures have been considered.
[0004]
For example, in Patent Document 1 (Japanese Patent Laid-Open No. 2002-198975), a frame error rate (FER) of transmission data is determined for each wireless link of a wireless LAN, and the frame error rate of the determination result is determined in advance. When the threshold value is exceeded, it is described that the quality of service is maintained by changing the channel frequency and switching to another radio link.
[0005]
[Patent Document 1]
JP 2002-198975 A.
[0006]
[Problems to be solved by the invention]
By the way, as the wireless LAN, for example, an IEEE (The Institute of Electrical and Electronics Engineers, Inc.) 802.11 standard is becoming widespread.
[0007]
In the case of the wireless LAN of the IEEE 802.11 standard, there is one connection between a wireless LAN access point device (hereinafter simply referred to as an access point device) and a wireless LAN terminal side station device (hereinafter simply referred to as a station device). Frequency is used. The CSMA / CA (Carrier Sense Multiple Access With Collision Avoidance Method) system avoids collision and enables simultaneous communication between a plurality of station devices and access point devices. ing.
[0008]
In this case, the allowable transmission band as a whole of one or more wireless links (wireless transmission paths) formed in the wireless LAN formed between the access point device and the plurality of station devices is determined. When transmitting and receiving streaming information such as telephone audio and video information using this wireless LAN, when attempting to transmit and receive data exceeding the allowable transmission band of the wireless LAN, so-called packet discard occurs, and transmission information When is audio information or video information, sound quality and image quality are impaired.
[0009]
Therefore, in general, a transmission device for wireless LAN is designed not to exceed the allowable transmission band of the wireless LAN,
(1) In a wireless LAN, the transmission band changes because the transmission speed is changed depending on the transmission distance, the presence or absence of an obstacle, and the like.
[0010]
(2) When a plurality of transmission paths (wireless links) are set for one wireless LAN access point device, the terminal side cannot recognize that another terminal is connected to the access point device.
For this reason, a transmission path having an amount of transmission exceeding the allowable transmission band is set, thereby inhibiting the transmission quality of individual transmission information.
[0011]
In the technique of Patent Document 1 described above, the transmission quality of transmission information is ensured by switching the channel frequency, and therefore only one channel is used as between the access point apparatus and the station apparatus. Is not applicable.
[0012]
For this reason, conventionally, even when the entire wireless LAN line is congested, if a collision can be avoided by the above-described collision avoidance method, a new wireless transmission path is formed and transmission information is transmitted. It was difficult to maintain the transmission quality. When the transmission information is streaming information such as audio information and video information, there is a great demand for maintaining this quality.
[0013]
In view of the above points, an object of the present invention is to provide a wireless LAN system capable of preventing deterioration in transmission quality of streaming information such as audio information and video information.
[0016]
[Means for Solving the Problems]
In order to solve the above problems, in the invention of claim 1,
  A wireless LAN (Local Area Network) access point device, and one or a plurality of wireless LAN terminal side station devices connected to the access point device through a wireless LAN, are configured through the wireless LAN. In a wireless LAN system in which streaming information is included in transmitted information,
  The access point device is
  Connected to the server device,
  Computing means for computing the required transmission bandwidth required by the streaming information transmitted and received through the wireless LAN;
  Discriminating means for discriminating whether or not the necessary transmission band obtained by the calculating means exceeds a predetermined threshold value in consideration of the quality of the streaming information;
  A control signal sending means for sending control information indicating that the required transmission band exceeds the threshold to the server device when the determining means determines that the required transmission band exceeds the threshold;
  With
  The server device
  Communication path addition prohibiting means for prohibiting addition of an information communication path in the wireless LAN when receiving control information indicating that the necessary transmission band exceeds the threshold value
  It is characterized by that.
[0017]
[Action]
  Of the above configurationThis inventionIn, the access point device analyzes the information signal passing through itself and calculates and obtains the necessary transmission band required for the streaming information transmitted through the wireless LAN. Next, it is determined whether or not the required transmission band thus obtained exceeds a predetermined threshold in consideration of the quality of streaming information. If it is determined that the required transmission band has been exceeded, a new one is added to the wireless LAN by the communication path addition prohibiting means. Addition of information communication path is prohibited.
[0018]
For this reason, the necessary transmission band of the streaming information transmitted through the wireless LAN can be within the transmission band capable of maintaining the quality of the streaming information, and the deterioration of the quality of the streaming information transmitted through the wireless LAN is prevented. be able to.
[0019]
  Channel addition prohibition meansIsServer device connected to the access pointIn placeCan be provided.
[0020]
  And the communication path addition prohibition means is claimed2As described above, and means for sending a wireless LAN unusable notification to the new information senderDoThis can be realized by letting the new information transmission side give up forming a transmission path.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a wireless LAN system according to the present invention will be described below with reference to the drawings.
[0022]
FIG. 1 is a block diagram showing an example of the overall configuration of the wireless LAN system of this embodiment. This embodiment is an example of a telephone communication system using a wireless LAN. The wireless LAN in this example is compliant with the IEEE 802.11 standard, and call voice information and call control information are packetized and transmitted.
[0023]
In FIG. 1, reference numeral 10 denotes a wireless LAN access point device (hereinafter simply referred to as an access point device), which is connected to the server device 12 through a wired LAN 11. In the case of the telephone communication system of this example, the server apparatus 12 serves as a telephone communication relay / switching apparatus (for example, corresponding to the main apparatus of the button telephone apparatus). In FIG. 2, the network is also connected to a public switched telephone network (PSTN) 14.
[0024]
The access point device 10 is provided with one or a plurality of wireless LAN terminal side station devices (hereinafter simply referred to as station devices) 21, 22,..., 2n (n is an integer of 1 or more). Are connected by wireless links. A wireless link formed between the access point device 10 and the station devices 21, 22,..., 2n constitutes a wireless LAN 15.
[0025]
In this example, packet telephones 31, 32,..., 3n as examples of communication terminals are connected to the station devices 21, 22,.
[0026]
The server device 12 manages address information on the wireless LAN 15 for packet telephones 31, 32,..., 3n connected to the wireless LAN 15 via station devices 21, 22,. .
[0027]
Then, the server device 12 uses this managed address information, and in this embodiment, any one of the packet telephones 31, 32,..., 3n and the packet telephones 31, 32,. ..., So-called extension calls can be made with the other packet telephones of 3n through the wireless LAN 15 and the server device 12.
[0028]
Incoming calls coming from the other party through the external network 14 are delivered to the server device 12 through the gateway 13. The server device 12 analyzes the information of the incoming call, and when the information specifying the specific packet telephone among the packet telephones 31, 32,..., 3n is included, it is addressed to the packet telephone. In other cases, the incoming call information is packetized to all packet telephones and sent to the station devices 21, 22,..., 2n through the access point device 10 and the wireless LAN 15.
[0029]
The station devices 21, 22,..., 2n transfer the incoming call to the packet telephones 31, 32,. The packet telephones 31, 32,..., 3n notify the user of the incoming call by, for example, ringing a bell. When one of the packet telephones 31, 32,..., 3n responds to this incoming call, the response message is transmitted from the packet telephone that has made the response to the access point apparatus 10 through the station apparatus and through the wireless LAN 15. The
[0030]
The access point device 10 sends a response to the external network 14 through the gateway 13 and notifies the other party. As a result, a call path through the wireless LAN 15 is formed, and voice packets are transmitted through the wireless LAN 15 to make a call.
[0031]
When one of the packet telephones 31, 32,..., 3n performs a call origination operation, the call destination is received via a route opposite to the above, and the call destination is answered. For example, a communication path through the wireless LAN 15 is formed, and voice packets are transmitted through the wireless LAN 15 to make a call.
[0032]
In this case, in this embodiment, the access point device 10 analyzes the communication packet to determine the communication congestion status in the wireless LAN 15, and if the communication is increased further, the quality of the call voice as streaming information cannot be maintained. , 2n is transmitted as control information to the station apparatuses 21, 22,..., 2n through the wireless LAN 15.
[0033]
A station device that is not communicating for a call through the wireless LAN 15 receives this control information and transfers the control information to the packet telephone to which it is connected.
[0034]
The packet telephone set that has received the control information recognizes the prohibition of the formation of an additional transmission path due to communication congestion of the wireless LAN 15, and performs an operation for that purpose. That is, in this embodiment, a communication path addition prohibition unit is provided in the packet telephone.
[0035]
In this example, this communication path addition prohibition means, when receiving a call request from the user when receiving notification of communication congestion of the wireless LAN 15, sends a busy tone to the user through the handset of the packet telephone, for example, Functional means for notifying that the LAN 15 is unusable due to congestion is included.
[0036]
In addition, the communication path addition prohibition means, when receiving a notification of communication congestion of the wireless LAN 15, when an incoming call is received by the packet telephone, the packet telephone cannot be used for the incoming call due to the congestion of the wireless LAN 15. It includes a function of sending information indicating the fact to the station device. The station device sends information indicating that the wireless LAN 15 cannot be used due to congestion to the server device 12 via the wireless LAN 15 and the access point device 10.
[0037]
Then, the server device 12 that has received information indicating that the wireless LAN 15 cannot be used due to congestion, sends the incoming call to the other party (packet telephone in the case of an internal incoming call, gateway in the case of an external incoming call, and The other party through the external network is notified that the incoming call due to congestion is impossible.
[0038]
As described above, the wireless link is added while the wireless LAN 15 is congested to prevent the quality of the voice of the call currently being communicated from being deteriorated, and a new call path with a poor call quality is newly added. Can also be prevented.
[0039]
<Hardware Configuration of Access Point Device 10>
FIG. 2 is a block diagram illustrating a hardware configuration example of the access point device 10.
[0040]
The access point device 10 in this example includes a control unit 101 made of, for example, a microcomputer, a wired LAN interface (in the figure, the interface is described as I / F; the same applies hereinafter) 102, a transmission processing circuit 103, and a reception process. The circuit 104, the transmission amplifier 105, the reception amplifier 106, the antenna distribution circuit 107, the transmission antenna 108, and the reception antenna 109 are configured.
[0041]
In this example, the wired LAN interface 102 is connected to the server device 12 through the wired LAN 11. The transmission antenna 108 and the reception antenna 109 are for transmitting and receiving packets through the wireless LAN 15.
[0042]
In the access point device 10, the transmission packet from the server device 12 obtained through the wired LAN interface 102 is transmitted via the transmission processing circuit 103 and the amplifier 105 and the antenna distribution circuit 107 in accordance with the control of the control unit 101. The signal is supplied to the antenna 108 and wirelessly transmitted to the station device.
[0043]
A packet from the station apparatus received through the reception antenna 109 is supplied to the reception processing circuit 104 through the antenna distribution circuit 107 and the amplifier 106. The packet from the reception processing circuit 104 is supplied to the control unit 101.
[0044]
The control unit 101 analyzes the received packet, and when it is a voice information packet or a call control packet, sends it to the server device 12 through the wired LAN interface 102 and the wired LAN 11.
[0045]
The server device 12 analyzes the call control packet when the received packet is a call control packet, and sends the packet to the external network 14 through the gateway 13 when the packet is transmitted to the outside. As a result of the analysis, if it is a call control packet for an extension call, it is sent to the access point device 10 through the wired LAN 11.
[0046]
The access point apparatus 10 receives this via the wired LAN interface 102, supplies it to the transmission antenna 108 via the transmission processing circuit 103 and the amplifier 105 and the antenna distribution circuit 107, and wirelessly transmits it to the station apparatus.
[0047]
The control unit 101 has functions as shown in the functional blocks of FIG. 2 as functions realized by software using a microcomputer.
[0048]
As described above, a voice packet and a control packet of a message for call control are transmitted to the wireless LAN 15, and the access point device 10 identifies the type of the packet from the packet header information. It has a function. That is, the control unit 101 of the access point device 10 determines the type of packet whether the packet passing through the access point device 10 is a packet that transmits voice information or a packet that transmits control information or other information. The packet identification means 111 for identifying from the packet header information is provided.
[0049]
Then, the information of the voice packet among the packets identified by the packet identifying unit 111 is sent to the necessary transmission band calculating unit 112. The necessary transmission band calculation means 112 calculates and determines a transmission band required by the voice information by the number of voice packets, the voice packet length, and the transmission rate every unit time consisting of a predetermined fixed time. That is, for a voice packet that has been transmitted / received through the wireless LAN 15 and passed through the access point device 10 during a unit time, the required transmission band for the voice information is obtained from the number of packets, the packet length, and the transmission rate.
[0050]
In this case, when the voice packet is transmitted by unicast, the access point device 10 determines the voice packet according to the distance of the other terminal (packet telephone through the station device). The distance from the counterpart terminal can be calculated, for example, from the received electric field strength. In the case of multicast audio, the access point device 10 calculates the minimum audio transmission rate.
[0051]
The necessary transmission band information for the voice information being communicated obtained by the necessary transmission band calculation means 112 is supplied to the wireless LAN state determination means 113. The wireless LAN state determination unit 113 is configured with a preset threshold value including an allowable transmission band for voice information that cannot maintain the quality of voice information when communication is further increased, and a necessary transmission band calculation unit 112. Compare with the required transmission bandwidth.
[0052]
Then, the determination result of the wireless LAN state determination unit 113 is supplied to the wireless LAN state signal transmission unit 114. When the comparison result in the wireless LAN state determination unit 113 indicates that the required transmission band is smaller than the threshold, the wireless LAN state signal transmission unit 114 can perform normal operation. As the status signal, control information indicating “normal operation” is transmitted to the wireless LAN 15.
[0053]
The wireless LAN status signal sending means 114, when the comparison result in the wireless LAN status judgment means 113 indicates that the necessary transmission band exceeds the threshold value, allows the wireless LAN 15 to have more wireless transmission paths. If it is increased, it is determined that the quality of the voice information cannot be maintained, and control information indicating “pass busy” indicating that the wireless LAN 15 cannot be used due to congestion is transmitted to the wireless LAN 15 as a status signal of the wireless LAN 15.
[0054]
<Hardware configuration of station device>
Each of the station devices 21, 22,..., 2 n basically has the same configuration as that of the access point device 10. FIG. 3 shows a block diagram of a configuration example of the station apparatus.
[0055]
That is, each of the station devices includes, for example, a control unit 201 formed of a microcomputer, a terminal interface 202, a transmission processing circuit 203, a reception processing circuit 204, a transmission amplifier 205, a reception amplifier 206, and an antenna distribution circuit. 207, a transmission antenna 208, and a reception antenna 209.
[0056]
In this example, the terminal interface 202 is connected to each packet telephone. The transmission antenna 208 and the reception antenna 209 are for transmitting and receiving packets through the wireless LAN 15.
[0057]
Each of the station devices transmits a packet of a call setting message from the packet telephone and a packet of voice communication information to the access point device 10 through the transmission antenna 208. Also, the received packet from the access point device 10 is sent to the packet telephone through the terminal interface 202.
[0058]
<Example of hardware configuration of packet phone>
The packet telephones 31, 32,..., 3n have the same hardware configuration. FIG. 4 shows a hardware configuration example of one packet telephone. As shown in FIG. 4, the packet telephone of this embodiment includes a terminal body 300 and a handset HS. Although not shown, the handset HS includes a microphone that constitutes a transmitter, a transmission amplifier, a speaker that constitutes a receiver, and a reception amplifier.
[0059]
The terminal main body 300 is configured by a computer. A ROM (Read Only Memory) 312, a RAM (Random Access Memory) 313, and a display controller are connected to a CPU (Central Processing Unit) 310 via a system bus 311. 314, an operation input interface 316, a station interface 318, a packet decomposition / generation unit 319, and an audio data input / output interface 320 are connected.
[0060]
A display 315 is connected to the display controller 314, and a display according to the control of the CPU 310 is performed on the display screen of the display 315.
[0061]
The operation input interface 316 is connected to an operation input unit 317 including numeric keys, cursor keys, and other operation keys. The CPU 310 recognizes which input key the user has operated through the operation input unit 317 via the operation input interface 316, and executes processing corresponding to the key input operation according to the program of the ROM 312 based on the recognition result. To do.
[0062]
The ROM 312 stores a program for executing a processing sequence at the time of transmission or reception according to a status signal of the wireless LAN 15, a program for executing other processing, and the like. In this example, the communication path addition prohibiting means is configured as one of the software programs.
[0063]
The RAM 313 is mainly used as a work area when the program of the ROM 312 is executed by the CPU 310.
[0064]
The station interface 318 is connected to the station device, and has a function of capturing packetized data transmitted through the station device and transmitting the packetized data to the LAN 31A.
[0065]
The packet disassembly / generation unit 319 disassembles the packetized data received by the interface 318 to obtain control data and audio data, and generates packetized data that is packetized from the control data and audio data to be transmitted and transmitted. It has a function. The packet decomposition / generation unit 319 includes a buffer memory for decomposing and generating packetized data.
[0066]
The packet decomposition processing function and the generation processing function of the packet decomposition / generation unit 319 can also be realized as software by the CPU 310 and the ROM 312.
[0067]
The audio data input / output interface 320 converts audio data obtained by packet decomposition into an analog audio signal and supplies the analog audio signal to the handset HS, and converts an analog audio signal input from the handset HS into a digital signal and takes it in. It has a function.
[0068]
<Processing of access point device>
Each time a packet transmitted through the wireless LAN 15 passes through the access point apparatus 10, the access point apparatus 10 performs packet statistical processing. FIG. 5 is a flowchart for the processing.
[0069]
That is, the control unit 101 of the access point apparatus 10 determines whether or not a packet transmitted through the wireless LAN 15 has passed (step S1), and executes other processing when it has not determined that a packet has passed (step S1). S2). If it is determined in step S1 that a packet transmitted through the wireless LAN 15 has passed, it is determined whether the packet is a voice packet or not (step S3).
[0070]
And it isolate | separates into a voice packet and another packet, The information of those packets is accumulate | stored (step S4). After step S4, the process returns to step S1 to repeat the above operation.
[0071]
Then, the access point device 10 starts the processing routine of FIG. 6 for every unit time consisting of the predetermined time described above, and calculates the necessary transmission band for the voice information transmitted through the wireless LAN 15. Ask.
[0072]
That is, first, the control unit 101 of the access point device 10 needs the voice information of the voice packets accumulated during the unit time using the number of packets, the packet length, and the transmission speed of each packet. A transmission band (necessary transmission band) to be calculated is calculated (step S11).
[0073]
Next, it is determined whether or not the calculated required transmission band exceeds a threshold value that is set in advance and that is composed of an allowable transmission band for voice information that cannot maintain the quality of voice information when communication is further increased ( Step S12).
[0074]
If it is determined in step S12 that the required transmission bandwidth thus obtained does not exceed the threshold value, “normal operation” indicating that a wireless communication path can be added as a state information signal (control packet) of the wireless LAN 15. Are transmitted to the station devices 21, 22,..., 2n through the wireless LAN 15 (step S13).
[0075]
Further, when it is determined in step S12 that the required transmission bandwidth thus obtained exceeds the threshold, “path busy” indicating prohibition of addition of a wireless communication path is indicated as a state information signal (control packet) of the wireless LAN 15. , 2n are transmitted to the station devices 21, 22,..., 2n through the wireless LAN 15 (step S14).
[0076]
The state information signal sent from the access point device 10 in steps S13 and S14 is transferred to the connected packet telephones through the station device that is not communicating through the wireless LAN 15.
[0077]
When the transmission of the status information signal is completed, the control unit 101 of the access point apparatus 10 discards the statistical information of the packets accumulated so far (step S15), and exits the processing routine of FIG.
[0078]
<Processing operation of packet phone>
The operation of the packet telephone when receiving the state information signal of the wireless LAN 15 will be described with reference to the flowcharts of FIGS.
[0079]
That is, the CPU 310 of the packet telephone determines whether or not a status information signal packet has been received (step S21). When it is determined that the packet has not been received, other processing is performed (step S22). If it is determined in step S21 that the status information signal packet has been received, the CPU 310 analyzes the received status information signal (step S23), and determines whether it is “normal operation” or “pass busy”. (Step S24).
[0080]
If it is determined in step S24 that the operation is “normal operation”, the CPU 301 writes “normal operation” in the state information storage area of the wireless LAN 15 of the RAM 313, for example (step S25). If it is determined in step S24 that “pass busy”, the CPU 310 writes “pass busy” in the state information storage area of the wireless LAN 15 in the RAM 313 (step S26). And after step S25 or step S26, it returns to step S21 and repeats the above-mentioned operation | movement.
[0081]
Next, processing when an incoming (incoming) call is received by the packet telephone will be described with reference to the flowchart of FIG.
[0082]
The CPU 310 of the packet telephone determines whether there is an incoming call (step S31), and if not, performs other processing (step S32).
[0083]
When determining that there is an incoming call, the CPU 310 refers to the status information signal area in the RAM 313 (step S33), and determines whether the state of the wireless LAN 15 is pass busy (step S34).
[0084]
When the status information signal area of the RAM 313 is “normal operation” and it is determined that the path is not busy, the CPU 310 makes a ringing ring at the packet telephone (step S35) and shifts to a normal incoming call processing routine. .
[0085]
If it is determined in step S34 that the state of the wireless LAN 15 is path busy, the CPU 310 sends “busy” information indicating that the wireless LAN 15 is unusable due to congestion through the station device and the access point device 10. Return to the server device 12 (step S36). Then, this processing routine ends.
[0086]
As described above, when the state information of the wireless LAN 15 is in the “pass busy” state, the server device 12 receives the “busy” information from the packet telephone. When the server device 12 receives this “busy” information, the server device 12 notifies the fact to the outgoing packet telephone in the case of an extension call. Upon receiving this notification, the outgoing packet telephone makes the user listen to a busy sound, for example. Then, since the user who made the call recognizes that the call is not possible and stops the call, a new wireless communication path is not formed in the wireless LAN 15, and the quality of the voice information being transmitted is maintained. The
[0087]
Next, processing in the case where a packet telephone has made a call (calling) will be described with reference to the flowchart of FIG.
[0088]
First, the CPU 310 of the packet telephone determines whether or not there has been an outgoing operation by the user (step S41). When it is determined that the user has not made a call operation, other processing is performed (step S42).
[0089]
If it is determined in step S41 that the user has made a call operation, the CPU 310 refers to the status information signal area in the RAM 313 (step S43), and determines whether the state of the wireless LAN 15 is pass busy (step S44).
[0090]
When it is determined that the status information signal area of the RAM 313 is “normal operation” and is not pass busy, the CPU 310 shifts to a normal call processing routine in the packet telephone.
[0091]
If it is determined in step S44 that the state of the wireless LAN 15 is pass busy, the CPU 310 sends the busy LAN handset HS indicating that the wireless LAN 15 cannot be used due to congestion (step S36). Then, this processing routine ends.
[0092]
As described above, when the state information of the wireless LAN 15 is in the “pass busy” state, the user who performed the call operation stops the transmission by listening to the busy sound from the handset HS handset. A new wireless communication path is not formed in the wireless LAN 15, and the quality of audio information being transmitted is maintained.
[0093]
An operation sequence in the above wireless LAN system is shown in FIG. That is, the access point device 10 sends the state information of the wireless LAN 15 to the packet telephone through the station device at regular intervals. While the wireless LAN 15 is in the “normal operation” state, the packet telephone can receive incoming calls and can make outgoing calls.
[0094]
However, when the access point device 10 detects “pass busy” as the state of the wireless LAN 15, “pass busy” is sent as state information to the packet telephone through the station device. For this reason, when there is an incoming call to the packet telephone, the packet telephone returns “busy” to the incoming call, does not respond to the incoming call, and the formation of a new wireless communication path is prohibited.
[0095]
If the call operation is a packet telephone in the “pass busy” state, busy is notified to the calling user, and the formation of a new wireless communication path is prohibited.
[0096]
[Other Embodiments]
The above embodiment is a case where the communication path addition prohibiting means is provided in the packet telephone, but the communication path addition prohibiting means can also be provided in the station device, for example, by its software.
[0097]
In this case, as shown in FIG. 11, the state information signal of the wireless LAN 15 from the access point device 10 may be sent to the station devices 21, 22,..., 2n, and the station devices 21, 22,. .., 2n need not have a function of transferring the state information signal of the wireless LAN 15 to the packet telephones 31, 32,.
[0098]
In the case of the example of FIG. 11, in the “pass busy” state, when an incoming call arrives at the packet telephone, the incoming call does not reach the packet telephone, and the station apparatus returns busy for the incoming call. In addition, when a call is made from the packet telephone, the station device returns a busy to the packet telephone, and the packet telephone receiving the call sends a busy sound to the user.
[0099]
Further, the communication path addition prohibiting means may be provided in the server device 12 instead of the packet telephone or the station device. In that case, as shown in FIG. 12, the state information signal of the wireless LAN 15 from the access point device 10 is sent to the server device 12.
[0100]
In the case of the example of FIG. 12, in the “pass busy” state, the server device 12 returns busy for incoming calls, and when there is a call from a packet telephone, the server device 12 returns a busy to the packet telephone via the access point device 10 and the station apparatus, and the packet telephone that receives this returns a busy sound to the user.
[0101]
Moreover, although the above embodiment is an example at the time of applying a wireless LAN system to a telephone system, it cannot be overemphasized that it is not restricted to this.
[0102]
That is, the present invention can also be applied to a wireless LAN system that packetizes AV (Audio Visual (audio information and video information)) information as shown in FIG.
[0103]
That is, also in FIG. 13, the access point device 10 and the station devices 21, 22,. Then, the AV server device 120 is connected to the access point device 10 through the LAN 11.
[0104]
The station devices 21, 22,..., 2n are connected to AV transmission devices 41, 42,.
[0105]
In the system of FIG. 13, AV transmission devices 41, 42,..., 4 n download AV information from server device 120 and upload AV information to server device 120. Also, AV information is transferred from one of the AV power transmission devices 41, 42,..., 4n to the other via the server device 120.
[0106]
Also in the case of the system of FIG. 13, by configuring the access point device 10 to detect the path busy state of the wireless LAN 15, the same processing operation as described above can be performed, and the same operation as in the above embodiment is performed. The effect is obtained.
[0107]
[Other variations]
In the above-described embodiment, the station device has a configuration of an adapter that is separate from the terminal device. However, the configuration of the adapter is not limited to a configuration that is connected to the terminal device with a cable. . For example, the station device may have a card type configuration, and the terminal device and the station device may be connected by inserting the card into the terminal device.
[0108]
The station device may be built in the terminal device.
[0109]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a wireless LAN system that can prevent deterioration in transmission quality of streaming information such as audio information and video information.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of a wireless LAN system according to the present invention.
FIG. 2 is a block diagram showing a configuration example of an access point device used in an embodiment of a wireless LAN system according to the present invention.
FIG. 3 is a block diagram showing a configuration example of a station apparatus used in an embodiment of a wireless LAN system according to the present invention.
FIG. 4 is a block diagram showing a configuration example of a packet telephone used in an embodiment of a wireless LAN system according to the present invention.
FIG. 5 is a flowchart for explaining processing in the embodiment of the wireless LAN system according to the present invention;
FIG. 6 is a flowchart for explaining processing in the embodiment of the wireless LAN system according to the present invention;
FIG. 7 is a flowchart for explaining processing in the embodiment of the wireless LAN system according to the present invention;
FIG. 8 is a flowchart for explaining processing at the time of an incoming call in the embodiment of the wireless LAN system according to the present invention;
FIG. 9 is a flowchart for explaining processing at the time of calling in the embodiment of the wireless LAN system according to the present invention;
FIG. 10 is a processing sequence diagram for explaining a processing operation in the embodiment of the wireless LAN system according to the present invention.
FIG. 11 is a processing sequence diagram for explaining a processing operation in another embodiment of the wireless LAN system according to the present invention.
FIG. 12 is a processing sequence diagram for explaining a processing operation in another embodiment of the wireless LAN system according to the present invention.
FIG. 13 is a configuration diagram of another embodiment of a wireless LAN system according to the present invention.
[Explanation of symbols]
10 Access point device
12 Server device
21, 22, ..., 2n Station device
31, 32, ..., 3n Packet telephone

Claims (3)

A wireless LAN (Local Area Network) access point device, and one or a plurality of wireless LAN terminal side station devices connected to the access point device through a wireless LAN, are configured through the wireless LAN. In a wireless LAN system in which streaming information is included in transmitted information,
The access point device is
Connected to the server device,
Computing means for computing the required transmission bandwidth required by the streaming information transmitted and received through the wireless LAN;
Discriminating means for discriminating whether or not the necessary transmission bandwidth obtained by the computing means exceeds a predetermined threshold value in consideration of the quality of the streaming information;
A control signal sending means for sending control information indicating that the required transmission band exceeds the threshold to the server device when the determining means determines that the required transmission band exceeds the threshold;
With
The server device
A wireless LAN system, comprising: communication path addition prohibiting means for prohibiting addition of an information communication path in the wireless LAN when receiving control information indicating that the necessary transmission band exceeds the threshold. The wireless LAN system according to claim 1 ,
The communication path addition prohibition means is
While the control information recognizes that the required transmission band exceeds the threshold, information transmission as an addition of an information communication path in the wireless LAN is prohibited and a transmission request from the terminal-side station device When the wireless LAN system is received, the wireless LAN system comprises means for sending a wireless LAN unusable notification to the terminal station device side. In the wireless LAN system according to any one of claims 1 to 2,
The calculation means calculates a necessary transmission band required by the streaming information transmitted within the predetermined period at a predetermined period,
The determining means determines whether or not the required transmission bandwidth obtained by the calculating means exceeds a predetermined threshold in consideration of the quality of the streaming information at the fixed period,
The wireless LAN system, wherein the control information sending means sends control information indicating a result of discrimination by the discrimination means to the server device at the fixed period.

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