JP2008236108A - Control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To connect radio devices to an electric supply hub as many as possible, while maintaining safe operation of a communication system. <P>SOLUTION: A LAN-IF portion 50 assigns channels in a wireless network to connect a plurality of radio devices for performing communications with a terminal device, respectively, via an electric supply hub. In addition, a network IF portion 54 connects a network 14. A processing portion 52 connects a channel for the wireless network at each of the plurality of radio devices to a channel in a communication network. The processing portion 52 acquires power consumption at the plurality of radio devices based on the allocation condition of channels in the plurality of radio devices. Moreover, the processing portion 52 compares the acquired power consumption with a threshold according to power which can be supplied to the plurality of radio devices from electric supply hub to control operation of the plurality of radio devices. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a control technique, and more particularly to a control device that connects a plurality of wireless devices.

A wireless communication system such as a second generation cordless telephone system is composed of a base station device and a terminal device. In such a wireless communication system, it is desired to expand the service area and effectively use the frequency. Therefore, a service area provided by one base station apparatus is reduced to some extent, and a plurality of base station apparatuses that repeatedly use the frequency are arranged (see, for example, Patent Document 1).
JP 9-163432 A

  The base station apparatus of the second generation cordless telephone system has a function of transmitting / receiving data to / from the terminal apparatus (hereinafter referred to as “transmission / reception function”). Furthermore, the base station apparatus is also connected to a communication network, and has a function (hereinafter referred to as “call control function”) for connecting a slot assigned to a terminal apparatus and a channel in the communication network. That is, the base station device defines a frame composed of a plurality of slots, and realizes communication with the terminal device by assigning a predetermined slot to the terminal device. Further, data is relayed between the terminal device and the communication network. The call control function includes setting of a secret key. In recent years, for the purpose of simplifying the configuration of a base station apparatus and the like, it has been proposed to separate such functions of the base station apparatus into a plurality of apparatuses.

  That is, the base station apparatus is separated into a radio apparatus and a control apparatus. Here, the transmission / reception function of the base station apparatus is mounted on the radio apparatus, and the call control function of the base station apparatus is mounted on the control apparatus. The wireless device and the control device are connected by a wired cable such as a LAN cable, but the configuration of the entire system can be simplified by connecting a plurality of wireless devices to one control device. At that time, the control device executes call control for a plurality of wireless devices. On the other hand, there is a PoE (Power over Ethernet) as a technique for supplying power using a cable used for Ethernet (registered trademark) wiring. Such PoE is applicable to the above-described wireless device and control device. That is, one end of the power supply hub is connected to the control device via the cable, and the other end of the power supply hub is connected to the wireless device via the cable. In such a configuration, the power supply hub supplies power to the wireless device.

  The maximum supply power of the power supply hub is defined as a predetermined value. The power consumption of the wireless device varies depending on the slot allocation status. In order to operate the communication system safely, the number of wireless devices connected to the power supply hub should be determined based on the maximum power consumption of the wireless devices. However, when such a determination is made, the number of wireless devices tends to decrease. When the power supply hub includes more connection terminals than the number of wireless devices, some of the connection terminals are not connected to the wireless device, and the connection terminals are wasted. Further, in order to expand the service area at a low cost, it is desirable that as many wireless devices as possible be connected to the power supply hub.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a control technique for connecting many wireless devices to a power supply hub while maintaining a safe operation of a communication system.

  In order to solve the above-described problem, a control device according to an aspect of the present invention connects a plurality of wireless devices each performing communication with a terminal device to one end via a power supply hub by assigning a channel in a wireless network. A communication unit that connects the communication network to the other end and connects a channel of the wireless network in each of the plurality of wireless devices and a channel in the communication network; and a plurality of wireless devices via the communication unit Comparing the means to acquire power consumption of multiple wireless devices based on channel allocation status, and the acquired power consumption and the threshold according to the power that can be supplied from the power supply hub to multiple wireless devices And a control unit including means for controlling operations of the plurality of wireless devices.

  A “channel” generally indicates a wireless communication path set for communication between two wireless devices. Specifically, the frequency division multiple access (FDMA) indicates a specific frequency band, the time division multiple access (TDMA) indicates a specific time slot or slot, and the case of CDMA (code division multiple access). Refers to a specific code sequence. Here, any of these may be used.

  According to this aspect, since the operation of a plurality of wireless devices is controlled according to the comparison result between the power consumption and the threshold value, the safe operation of the communication system is maintained so that the power consumption does not exceed the power that can be supplied. However, many wireless devices can be connected to the power supply hub.

  When the acquired power consumption increases, the control unit may limit the operations for the plurality of wireless devices. In this case, when the acquired power consumption increases, the operation for a plurality of wireless devices is restricted, so that the power consumption can be suppressed.

  Each of the plurality of wireless devices connected to the communication unit via the power feeding hub supports a plurality of types of modulation schemes, and when the acquired power consumption increases, the control unit The use of a modulation scheme having a small modulation multi-level number may be instructed. In this case, when the acquired power consumption increases, a modulation scheme with a small modulation multi-level number is used, so that power consumption can be suppressed.

  Each of the plurality of wireless devices connected to the communication unit via the power supply hub can execute transmission power control. When the acquired power consumption increases, the control unit transmits transmission power to the plurality of wireless devices. May be instructed to lower In this case, when the acquired power consumption increases, the transmission power is reduced, so that the power consumption can be suppressed.

  It should be noted that any combination of the above-described constituent elements and a conversion of the expression of the present invention between a method, an apparatus, a system, a recording medium, a computer program, etc. are also effective as an aspect of the present invention.

  According to the present invention, it is possible to connect many wireless devices to the power supply hub while maintaining the safe operation of the communication system.

  Before describing the present invention in detail, an outline will be described. Embodiments of the present invention relate to a communication system in which the functions of a base station apparatus are separated into a radio apparatus and a control apparatus. As described above, the wireless device communicates with the terminal device via the wireless network. Further, the control device communicates with the wireless device via the wired network at one end, and connects the communication network at the other end to execute connection between the channel of the wireless network and the channel of the communication network. Furthermore, a power supply hub is connected between the control device and the plurality of wireless devices, and the power supply hub supplies power to the plurality of wireless devices. Note that the power consumption of the wireless device varies depending on the channel assignment status of the wireless device.

  In the embodiment, it is assumed that the number of wireless devices connected to the power supply hub is such that power cannot be supplied by the power supply hub when each wireless device requires the maximum power consumption. That is, the entire service area is expanded by connecting many wireless devices. On the other hand, each wireless device periodically reports the channel assignment status to the control device. The control device estimates the power consumption in the plurality of wireless devices based on the channel allocation status, and restricts the operation in the plurality of wireless devices when the estimated power consumption increases. For example, when the wireless device supports a plurality of types of modulation schemes, the control device instructs the use of a modulation scheme with a small number of modulation multi-levels, or instructs not to accept new outgoing calls and incoming calls. . Such a restriction suppresses power consumption in a plurality of wireless devices and maintains the stability of the communication system.

  FIG. 1 shows a configuration of a communication system 100 according to an embodiment of the present invention. The communication system 100 includes a terminal device 10, a base station system 20, and a network 14. The base station system 20 includes a first wireless device 22a, a second wireless device 22b, a third wireless device 22c, a fourth wireless device 22d, and a single LAN cable 26, collectively referred to as a wireless device 22. A LAN cable 26 a, a second single LAN cable 26 b, a third single LAN cable 26 c, a fourth single LAN cable 26 d, a power supply hub 16, a common LAN cable 28, and a control device 24 are included.

  The wireless device 22 executes communication with the terminal device 10 by assigning a channel in the wireless network. That is, the wireless device 22 has a transmission / reception function for transmitting / receiving data to / from the terminal device 10. Therefore, the wireless device 22 has an amplification function, a frequency conversion function, a modulation / demodulation function, an error correction function, a retransmission function, and the like. In the case of the second generation cordless telephone system, the channel may be a slot. The wireless device 22 defines a frame composed of a plurality of channels. Here, it is assumed that the frame configuration is the same as the frame configuration in the second generation cordless telephone system. However, the wireless device 22 does not have a call control function. Here, the call control function corresponds to connecting a channel assigned to the terminal device 10 and a channel in the network 14. For the sake of clarity, four wireless devices 22 are shown in FIG. However, four or more wireless devices 22 may be included, for example, 16 wireless devices 22 are included.

  The power supply hub 16 has one end connected to the wireless device 22 via a single LAN cable 26 and the other end connected to the control device 24 via a common LAN cable 28. The power supply hub 16 relays data between the wireless device 22 and the control device 24. The power supply hub 16 supplies power to the wireless device 22. For example, the power supply hub 16 corresponds to PoE power supply conforming to the IEEE 802.3af standard. Here, the radio apparatus 22 supports a plurality of types of modulation schemes, and the power consumption in the radio apparatus 22 varies depending on the channel allocation status in the radio apparatus 22 and the modulation scheme used. . It is assumed that the maximum power that can be supplied by the power supply hub 16 is smaller than the sum of the maximum power consumption in each wireless device 22. For example, it is assumed that the maximum power that can be supplied by the power supply hub 16 is 100 W. The sum of the maximum power consumption in each wireless device 22 will be described later.

  The control device 24 is connected to the wireless device 22 at one end via the power supply hub 16 via the common LAN cable 28 and connected to the network 14 at the other end. With such a configuration, the control device 24 communicates with a plurality of wireless devices 22. The control device 24 connects the channel in the wireless device 22 and the channel in the network 14 by a call control function. In addition, control is performed on the plurality of wireless devices 22 such that the total power consumption of each of the plurality of wireless devices 22 is smaller than the power that can be supplied by the power supply hub 16. Although details of the contents of the control will be described later, in order to execute the control, the control device 24 receives information on the channel assignment status and the modulation method from the plurality of wireless devices 22.

  The network 14 connects the control device 24. The network 14 includes an exchange (not shown) and controls the communication path. The network 14 may be connected to another communication system 100. The channels in the network 14 include a D channel and a B channel.

  FIG. 2 is a sequence diagram showing a procedure for starting a call by the communication system 100. The first radio apparatus 22a transmits a control signal to the terminal apparatus 10 (S200). The terminal device 10 establishes timing synchronization with the first wireless device 22a based on the control signal (S202). The terminal device 10 transmits a link channel establishment request to the first wireless device 22a (S204). The first radio apparatus 22a transmits a link channel assignment to the terminal apparatus 10 (S206). The first radio apparatus 22a transmits TCH activation completion to the control apparatus 24 (S207). The terminal device 10 transmits the CC call setting to the first wireless device 22a (S208). The first wireless device 22a transmits the call setting to the control device 24 (S209). In addition, the control device 24 transmits call setting acceptance to the first wireless device 22a (S211). The first radio apparatus 22a transmits a CC call setting acceptance to the terminal apparatus 10 (S212). The terminal device 10 transmits an RT definition information request to the first wireless device 22a (S213). The first wireless device 22a transmits an RT definition information response to the terminal device 10 (S214).

  The terminal device 10 transmits an RT function request to the first wireless device 22a (S216). The first wireless device 22a transmits an RT function request response to the terminal device 10 (S218). The terminal device 10 transmits the RT secret key setting to the first wireless device 22a (S220). The terminal device 10 transmits an MM function request to the first wireless device 22a (S222). The first radio apparatus 22a transmits an MM function request response to the terminal apparatus 10 (S224). The first wireless device 22a transmits an authentication start to the control device 24 (S226). The control device 24 transmits an authentication request to the first wireless device 22a (S228). The first wireless device 22a transmits an authentication request to the terminal device 10 (S230). The terminal device 10 transmits an authentication response to the first wireless device 22a (S232). The first wireless device 22a transmits an authentication response to the control device 24 (S234).

  The control device 24 transmits the call setting to the network 14 (S236). The network 14 transmits a call setting acceptance to the control device 24 (S238). Through the above processing, the channel in the first radio apparatus 22a and the channel in the network 14 are connected. The network 14 transmits a call to the control device 24 (S240). The control device 24 transmits a call to the first wireless device 22a (S242). The first radio apparatus 22a transmits a CC call to the terminal apparatus 10 (S244). The network 14 transmits a response to the control device 24 (S246). The control device 24 transmits a response to the first wireless device 22a (S248). The first radio apparatus 22a transmits a CC response to the terminal apparatus 10 (S250). The control device 24 transmits a response confirmation to the network 14 (S252). The terminal device 10 and the network 14 execute a call (S254).

  In a general communication system, a base station device (not shown) has both a transmission / reception function and a call control function. Therefore, in FIG. 2, the process between the first radio apparatus 22a and the control apparatus 24, for example, step 226 or the like, is performed inside the base station apparatus. On the other hand, in the communication system 100 of FIG. 1, the wireless device 22 has a transmission / reception function, and the control device 24 has a call control function. With such a configuration, the wireless device 22 has a simpler configuration than the base station device. Further, by connecting the plurality of radio apparatuses 22 and the control apparatus 24, the base station system 20 has a configuration easier than that of the plurality of base station apparatuses.

  FIG. 3 shows the configuration of the first radio apparatus 22a. The first radio apparatus 22a includes an RF unit 30, a modulation unit 32, a demodulation unit 34, a processing unit 36, a LAN-IF unit 38, and a control unit 44. The wireless devices 22 other than the first wireless device 22a have the same function.

  As a function for reception in the transmission / reception function, the RF unit 30 receives a signal from the terminal device 10 (not shown) via the wireless network, and performs frequency conversion on the received signal. The demodulator 34 demodulates the frequency-converted signal. The processing unit 36 outputs the demodulated signal to the LAN-IF unit 38. On the other hand, the processing unit 36 receives a signal from the LAN-IF unit 38 as a function for transmission in the transmission / reception function. The modulation unit 32 modulates the received signal. The RF unit 30 performs frequency conversion on the modulated signal. The RF unit 30 transmits the frequency-converted signal to a terminal device 10 (not shown) via a wireless network.

  As described above, the first radio apparatus 22a can communicate with a plurality of terminal apparatuses 10. Channels are assigned to the plurality of terminal devices 10 by the processing unit 36. Here, the channel corresponds to a channel in the wireless network. The modulation unit 32 and the demodulation unit 34 correspond to a plurality of types of modulation schemes. Here, it is assumed that the plurality of types of modulation schemes are QPSK, 16QAM, and 64QAM. The modulation method is selected by the processing unit 36, but since a known technique may be used, description thereof is omitted here.

  Further, the power consumption of the first radio apparatus 22a varies depending on the modulation scheme and the channel allocation status. For example, the power consumption when assigning a channel to one terminal apparatus 10 using QPSK is “0.4 W”, but when the modulation method is 16 QAM and 64 QAM, the power consumption is “0.6 W”, “0.8W”. On the other hand, when allocating channels to 16 terminal apparatuses 10, the power consumption when the modulation scheme is QPSK, 16QAM, or 64QAM is “6.4W”, “9.6W”, or “12.8W”. In FIG. 1, four wireless devices 22 are shown. However, when 16 wireless devices 22 are connected to the power supply hub 16, the power consumption is about 16 times the above value. As a result, there may occur a case where the maximum power “100 W” that can be supplied by the power supply hub 16 is exceeded.

  The processing unit 36 periodically transmits to the control device 24 information regarding the channel allocation status, that is, how many terminal devices 10 the channel is allocated to and the modulation scheme, via the LAN-IF unit 38. For example, the processing unit 36 transmits these pieces of information at 100 msec intervals. The LAN-IF unit 38 is connected to the control device 24 (not shown) via the first single LAN cable 26a. The control unit 44 controls the timing of the entire apparatus.

  This configuration can be realized in terms of hardware by a CPU, memory, or other LSI of any computer, and in terms of software, it is realized by a program having a communication function loaded in the memory. Describes functional blocks realized by collaboration. Accordingly, those skilled in the art will understand that these functional blocks can be realized in various forms by hardware only, software only, or a combination thereof.

  FIG. 4 shows the configuration of the control device 24. The control device 24 includes a LAN-IF unit 50, a processing unit 52, a network IF unit 54, a storage unit 56, and a control unit 60. The LAN-IF unit 50 is connected to a wireless device 22 (not shown) via the common LAN cable 28 and the power supply hub 16 (not shown). The network IF unit 54 is connected to the network 14.

  The processing unit 52 connects a channel for the terminal device 10 (not shown) and a channel in the network 14 (not shown). With such a connection, the processing unit 52 executes control of switching of communication targets. That is, when the network IF unit 54 receives a signal from the network 14, the processing unit 52 outputs a signal to a predetermined wireless device 22 according to the destination included in the signal. The storage unit 56 records the channel allocation result in the processing unit 52. When executing the above processing, the processing unit 52 communicates with the wireless device 22 via the LAN-IF unit 50.

  The processing unit 52 periodically receives information on channel assignment status and modulation scheme from each of the plurality of wireless devices 22 via the LAN-IF unit 50. As described above, for example, information is received at 100 msec intervals. The processing unit 52 estimates power consumption in the plurality of wireless devices 22 based on the received information. For example, the storage unit 56 stores in advance a table in which information contents and power consumption are associated with each other, and the processing unit 52 refers to the table to calculate power consumption corresponding to each received information. get. It is assumed that the table is created based on experimental results and simulation results. Further, the processing unit 52 derives power consumption in the plurality of wireless devices 22 by integrating power consumption corresponding to each of the plurality of wireless devices 22.

  In addition, the storage unit 56 stores a threshold value corresponding to the power that can be supplied from the power supply hub 16 to the plurality of wireless devices 22. As described above, the power that can be supplied from the power supply hub 16 to the plurality of wireless devices 22 is 100 W, and the threshold value 1 and the threshold value 2 corresponding to this are stored. Further, the threshold value 1 corresponds to “80 W”, and the threshold value 2 corresponds to “95 W”. The processing unit 52 controls the operations of the plurality of wireless devices 22 by comparing the derived power consumption with the threshold values 1 and 2 stored in the storage unit 56. When the power consumption becomes larger than the threshold value 1, the processing unit 52 instructs the plurality of radio apparatuses 22 to use a modulation scheme with a small modulation multi-level number.

  Here, the modulation scheme having a small modulation multi-level number corresponds to QPSK. Further, when the power consumption becomes larger than the threshold value 2, the processing unit 52 instructs the plurality of wireless devices 22 not to accept new outgoing calls and incoming calls. Here, the instruction is output to the wireless device 22 via the LAN-IF unit 50. The control unit 60 controls the timing of the entire apparatus.

  The operation of the communication system 100 configured as above will be described. FIG. 5 is a flowchart showing a control procedure of the wireless device 22 by the control device 24. The processing unit 52 acquires the channel assignment status and modulation scheme in the wireless device 22 via the LAN-IF unit 50 (S10), and estimates power consumption (S12). If the power consumption is larger than the threshold value 1 (Y in S14), the processing unit 52 restricts the modulation method to QPSK (S16). If the power consumption is greater than the threshold value 2 (Y in S18), the processing unit 52 restricts outgoing calls and incoming calls (S20). On the other hand, if the power consumption is not greater than the threshold value 1 (N in S14), the processing unit 52 does not limit the wireless device 22 (S24). If the power consumption is not greater than the threshold value 2 (N in S18), the processing unit 52 does not limit outgoing calls and incoming calls (S22).

  According to the embodiment of the present invention, since the operations of the plurality of wireless devices are controlled according to the comparison result between the power consumption and the threshold value, the power consumption can be made smaller than the power that can be supplied. Further, since the power consumption is smaller than the power that can be supplied, the safe operation of the communication system can be maintained. In addition, since the power consumption is smaller than the power that can be supplied, a large number of wireless devices can be connected to the power supply hub. In addition, since many wireless devices can be connected to the power supply hub, the service area can be expanded. Moreover, since many radio | wireless apparatuses can be connected to an electric power feeding hub, the increase in cost can be suppressed. Further, when the acquired power consumption increases, outgoing and incoming calls in a plurality of wireless devices are restricted, so that power consumption can be suppressed. Further, when the acquired power consumption increases, a modulation scheme with a small modulation multi-level number is used, so that power consumption can be suppressed.

  In the above, this invention was demonstrated based on the Example. This embodiment is an exemplification, and it will be understood by those skilled in the art that various modifications can be made to the combination of each component and each processing process, and such modifications are also within the scope of the present invention. .

  In the embodiment of the present invention, the wireless device 22 transmits information on the channel allocation status and modulation scheme to the control device 24, and the control device 24 derives power consumption from these information. However, the present invention is not limited to this. For example, the wireless device 22 may derive power consumption from the channel allocation status and the modulation scheme, and transmit the derived power consumption to the control device 24. At that time, the control device 24 derives the power consumption in the plurality of wireless devices 22 by integrating the power consumption from each of the plurality of wireless devices 22. According to this modification, the process of the control device 24 can be simplified.

  In the embodiment of the present invention, the wireless device 22 transmits information on the channel allocation status and modulation scheme to the control device 24, and the control device 24 derives power consumption from these information. However, the present invention is not limited to this. For example, the control device 24 may estimate the power consumption from the connection status in the processing unit 52. According to this modification, traffic between the wireless device 22 and the control device 24 can be reduced.

  In the embodiment of the present invention, the processing unit 52 executes restriction on the modulation method, restriction on outgoing calls and incoming calls as control for the plurality of radio apparatuses 22. However, the present invention is not limited to this. For example, the processing unit 52 may execute only one of these. Moreover, you may perform restrictions other than these. According to this modification, the degree of freedom of the configuration of the base station system 20 can be improved.

  In the embodiment of the present invention, when the power consumption increases, the control device 24 instructs the plurality of wireless devices 22 to change the modulation method. However, the present invention is not limited thereto. For example, each of the plurality of wireless devices 22 connected to the LAN-IF unit 50 via the common LAN cable 28 can execute transmission power control, and the control device 24 can acquire the acquired power consumption. May increase, a plurality of wireless devices 22 may be instructed to reduce transmission power. According to this modification, when the acquired power consumption increases, the transmission power is reduced, so that the power consumption can be suppressed.

It is a figure which shows the structure of the communication system which concerns on the Example of this invention. It is a sequence diagram which shows the procedure of the telephone call start by the communication system of FIG. It is a figure which shows the structure of the 1st radio | wireless apparatus of FIG. It is a figure which shows the structure of the control apparatus of FIG. 5 is a flowchart showing a control procedure of a wireless device by the control device of FIG.

Explanation of symbols

  10 terminal devices, 14 networks, 16 power supply hubs, 20 base station systems, 22 wireless devices, 24 control devices, 26 single LAN cables, 28 common LAN cables, 30 RF units, 32 modulation units, 34 demodulation units, 36 processing units, 38 LAN-IF unit, 44 control unit, 50 LAN-IF unit, 52 processing unit, 54 network IF unit, 56 storage unit, 60 control unit, 100 communication system.

Claims (4)

By allocating channels in a wireless network, a plurality of wireless devices that respectively perform communication with a terminal device are connected to one end via a power supply hub, while a communication network is connected to the other end, and each of the plurality of wireless devices A communication unit for connecting a channel of the wireless network in the network and a channel of the communication network;
Means for acquiring power consumption in a plurality of wireless devices based on channel assignment status in the plurality of wireless devices, the acquired power consumption, and supplying from the power supply hub to the plurality of wireless devices via the communication unit A control unit including means for controlling operations of a plurality of wireless devices by comparing a threshold value according to possible power;
A control device comprising:   The control device according to claim 1, wherein when the acquired power consumption increases, the control unit restricts operations for a plurality of wireless devices. Each of a plurality of wireless devices connected to the communication unit via a power feeding hub supports a plurality of types of modulation schemes,
3. The control device according to claim 1, wherein when the acquired power consumption increases, the control unit instructs a plurality of wireless devices to use a modulation scheme having a small modulation multi-value number. 4. Each of a plurality of wireless devices connected to the communication unit via a power supply hub can execute transmission power control,
4. The control device according to claim 1, wherein when the acquired power consumption increases, the control unit instructs a plurality of wireless devices to reduce transmission power. 5.

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