JP5598980B2 - System and method for preventing interference between wireless communication networks - Google Patents

Description

  The present invention relates to a system and a method for preventing interference between radio communication networks, which are preferable when a plurality of radio communication networks coexist in the same space without interfering with each other.

  In recent years, the number of wireless communication system subscriptions has increased, and sophistication and diversification of services have progressed. At this time, when a plurality of wireless communication networks coexist in the same communication space and in the same frequency band, communication interference occurs.

  FIG. 4 shows an example in which communication interference occurs between such wireless communication networks. In this system 60, two wireless communication networks 40 and 50 coexist in the same space. The wireless communication network 40 includes a first network controller (NC) 41 and wireless terminals DEV1 and DEV2.

  The wireless terminals DEV1 and DEV2 are composed of, for example, notebook personal computers (notebook PCs), various portable information terminals such as mobile phones. Further, the first NC 41 may have the same configuration as the wireless terminals DEV1 and DEV2 described above. The first NC 41 is a device for controlling the entire communication within the wireless communication network 40. Further, even when packet communication is performed between the wireless terminal DEV1 and the wireless terminal DEV2, it may be executed via the first NC 41. In this sense, the first NC 41 serves as a base station. Will also bear. The wireless communication network 50 is provided with a second network controller (NC) 42 for controlling the entire communication in the network. The functions implemented in the second NC 42 are the same as those of the first NC 41 described above. The wireless communication network 50 also includes a wireless terminal (not shown) that can communicate with the second NC 42.

  Consider a case where data is transmitted from the wireless terminal DEV2 to the wireless terminal DEV1. A coherent range exists around the wireless terminal DEV1 that is a data transmission destination. When signals are transmitted / received by another wireless communication network 50 within a coherent range centered on the wireless terminal DEV1, communication interference occurs between the wireless communication networks 40 and 50. In the example of FIG. 4, interference occurs when there is a wireless terminal (not shown) constituting the wireless communication network 50 in an overlapping portion of the coherent range centered on the wireless terminal DEV1 and the communication range of the wireless communication network 50. It will occur.

  For this reason, a method for preventing interference between wireless communication networks that can coexist with a communication space without interfering with each other among a plurality of wireless communication networks has been demanded.

  For example, in a method of coexisting communication space by time-sharing between a plurality of wireless communication networks, a time frame composed of a plurality of time slots is divided into several time slot groups, and the divided time slot groups are respectively assigned to each system. Assign to.

  Further, in the method of coexisting communication space by dividing the frequency among a plurality of wireless communication networks, a certain frequency band is divided into two or more partial frequency bands, and the divided partial frequency bands are assigned to the respective systems.

  As conventional coexistence methods between wireless communication networks, for example, methods disclosed in Patent Documents 1 and 2 have been proposed.

US Pat. No. 5,732,076 US Patent Application 2008/247445

  However, there has been a demand for a system that can simplify the processing flow for preventing interference more than the frequency dividing method or the time dividing method described above.

  Therefore, the present invention has been devised in view of the above-mentioned problems, and the object of the present invention is between wireless communication networks for allowing a plurality of wireless communication networks to coexist without interfering with each other in the same space. In the interference prevention system and method, it is providing the interference prevention system and method between the radio | wireless communication networks which can simplify the process flow for interference prevention more.

The interference prevention system between wireless communication networks according to claim 1, wherein a first wireless communication network and a second wireless communication network each having a wireless terminal and a communication control device are present in the case where the first wireless communication network and the second wireless communication network exist in the same space. In the interference prevention system between the wireless communication networks, the wireless terminal A sends a first request signal indicating that the periphery of the wireless terminal B as the communication destination should be an interference free zone in the first wireless communication network. The first communication control apparatus that has transmitted to the communication control apparatus and received the request signal has a threshold value (hereinafter referred to as a coherence level) that is determined to cause communication interference in the wireless terminal B. To the second communication control device in the second wireless communication network, and the second communication control device For line terminal, the maximum value of the transmission level of the wireless terminal a wireless terminal (hereinafter, referred to as the maximum communication level.) Is calculated, the calculated maximum communication level exceeds the coherence level transmitted from the first communication controller Is characterized in that the communication level is lowered or the communication is stopped.

According to a second aspect of the present invention, there is provided a system for preventing interference between wireless communication networks according to the first aspect of the present invention, wherein the first communication control device that has received the request signal uses the second wireless device to obtain the position information of the wireless terminal B. The second communication control device identifies the coherence range of the wireless terminal B based on the location information of the wireless terminal B, and transmits the second wireless communication to the second communication control device in the communication network. Each position information is acquired from each wireless terminal in the network, it is determined whether or not the acquired position information falls within the identified coherence range, and it is determined that the position information falls within the coherence range and is calculated. For a wireless terminal whose maximum communication level exceeds the coherence level transmitted from the first communication control device, control is performed to lower the communication level or stop communication .

The interference prevention system between wireless communication networks according to claim 3 is the invention according to claim 2 , wherein the second communication control device acquires position information of a wireless terminal in the second wireless communication network. If the wireless terminal cannot acquire the position information, it is assumed that it is the closest position to the wireless terminal B among the possible positions of the wireless terminal, and whether or not it falls within the identified coherence range. It is characterized by distinguishing.

According to a fourth aspect of the present invention, there is provided a method for preventing interference between wireless communication networks, in which a first wireless communication network and a second wireless communication network each having a wireless terminal and a communication control device exist in the same space. In the method for preventing interference between wireless communication networks, a request signal indicating that the wireless terminal A should set an interference free zone around a wireless terminal B as a communication destination in the first wireless communication network is a first signal. A threshold value (hereinafter referred to as a coherence level) that is determined to cause communication interference in the wireless terminal B by the first communication control apparatus that has transmitted to the communication control apparatus and received the request signal is referred to as the second interference level. To the second communication control device in the second wireless communication network, and the second communication control device transmits each of the items in the second wireless communication network. The maximum value of the transmission level of each wireless terminal for the terminal (hereinafter, referred to as the maximum communication level.) Is calculated, the wireless terminal the calculated maximum communication level exceeds the coherence level transmitted from the first communication control unit The communication level is lowered or the communication is stopped.

According to a fifth aspect of the present invention, there is provided a method for preventing interference between wireless communication networks according to the fourth aspect of the present invention, wherein the position information of the wireless terminal B is obtained from the second wireless communication by the first communication control device that has received the request signal. The second communication control device transmits the second communication control device, and the second communication control device identifies the coherence range of the wireless terminal B based on the position information of the wireless terminal B, and the second wireless communication Each position information is acquired from each wireless terminal in the network, it is determined whether or not the acquired position information falls within the identified coherence range, and it is determined that the position information falls within the coherence range and is calculated. for a wireless terminal maximum communication levels exceeding coherence level transmitted from the first communication control device, to and performs control to stop or communications lowering the communication level .

According to a sixth aspect of the present invention, there is provided a method for preventing interference between wireless communication networks according to the fifth aspect of the invention, wherein the second communication control device acquires position information of wireless terminals in the second wireless communication network. If the wireless terminal cannot acquire the position information, it is assumed that it is the closest position to the wireless terminal B among the possible positions of the wireless terminal, and whether or not it falls within the identified coherence range. It is characterized by distinguishing.

  According to the present invention having the above-described configuration, a plurality of wireless communication networks can coexist in the same space without interfering with each other, and can be realized with an extremely simple processing flow, thereby reducing the load on the system. Is possible.

It is a figure which shows the structural example of the interference prevention system between the radio | wireless communication networks to which this invention is applied. It is a flowchart which shows the operation example of the interference prevention system between the radio | wireless communication networks to which this invention is applied. It is a figure which shows the operation example when 2nd NC cannot acquire the positional information on all the radio | wireless terminals. It is a figure for demonstrating the problem of a prior art.

  Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 shows a configuration example of an interference prevention system 10 between wireless communication networks to which the present invention is applied. The interference prevention system 10 includes two wireless communication networks 20 and 30. The wireless communication network 20 includes a plurality of wireless terminals DEV1, DEV2,... And a first network controller (NC) 21 that controls the entire network. The wireless communication network 30 includes a plurality of wireless terminals DEV3, DEV4, DEV5, DEV6,... And a second network controller (NC) 31 that controls the entire network.

  The wireless terminals DEV1 and DEV2 are configured by, for example, notebook personal computers (notebook PCs), various portable information terminals such as mobile phones and the like. The wireless terminals DEV 1 and 2 can perform wireless packet communication with the first NC 21, and further wireless packet communication with the wireless terminals DEV 2 and 1 as other devices via the first NC 21. I do. The wireless terminals DEV1 and DEV2 can identify their own positions in the respective wireless communication networks 20 and transmit them to the first NC 21 as position information. For this position identification, for example, a beam forming technique may be used. In the example of FIG. 1, a case where two wireless terminals DEV1 and DEV2 exist in the wireless communication network 20 is described as an example. However, the present invention is not limited to this, and one or more wireless terminals are provided. As long as it has a terminal DEV, it may be composed of any number.

  Similarly, the first NC 21 may have the same configuration as the wireless terminals DEV1 and DEV2 described above. The first NC 21 serves as a central control unit of the wireless communication network 20. And this 1st NC21 performs a processing operation with respect to each component contained in the radio | wireless communication network 20 based on the various information transmitted from radio | wireless terminal DEV1,2. The first NC 21 may also serve as a relay station or a base station for wireless communication with the wireless terminals DEV1 and DEV2. The first NC 21 can also acquire the position information of the wireless terminals DEV 1 and 2. As a result, the first NC 21 can identify the position of the wireless terminals DEV 1 and 2 based on the acquired position information. It becomes possible. The first NC 21 can also identify the communication levels of the wireless terminals DEV1 and DEV2. Note that the first NC 21 may identify the positions of the wireless terminals DEV1 and DEV2 via the power levels of the wireless terminals DEV1 and DEV2.

  The wireless terminals DEV3 to DEV6 are configured with, for example, notebook personal computers (notebook PCs), various portable information terminals such as mobile phones and the like. The wireless terminal DEV3-6 can perform wireless packet communication with the second NC31, and further, wireless packet communication with the wireless terminals 6-3 as other devices via the first NC31. I do. The wireless terminals DEV3 to DEV6 can identify their own positions in the respective wireless communication networks 30 and transmit them to the second NC 31 as position information. For this position identification, for example, a beam forming technique may be used. In the example of FIG. 1, the case where two wireless terminals DEV3 to 6 exist in the wireless communication network 30 is described as an example, but the present invention is not limited to this, and one or more wireless terminals are provided. As long as it has a terminal DEV, it may be composed of any number.

  Similarly, the second NC 31 may have the same configuration as the wireless terminals DEV3 to DEV6 described above. The second NC 31 plays a role as a central control unit of the radio communication network 20. And this 2nd NC31 performs a processing operation with respect to each component contained in the radio | wireless communication network 30 based on the various information transmitted from radio | wireless terminal DEV3-6. The second NC 31 may also serve as a relay station or a base station for wireless communication with the wireless terminals DEV3 to DEV6. The second NC 31 can also acquire the position information of the wireless terminals DEV3 to 6, and as a result, the first NC21 can identify the positions of the wireless terminals DEV3 to 6 based on the acquired position information. It becomes possible. The second NC 31 can also identify the communication levels of the wireless terminals DEV3 to DEV6. Note that the first NC 21 may identify the positions of the wireless terminals DEV3 to DEV6 via the power levels of the wireless terminals DEV3 to DEV6.

  The two wireless communication networks 20 and 30 are systems installed in the same or close spaces. These two wireless communication networks 20 and 30 may perform wireless communication between the respective NC 21 and the wireless terminals DEV 1 and 2 and between the NC 31 and the wireless terminals DEV 3 to 6 in mutually overlapping frequency bands. . Further, the two wireless communication networks 20 and 30 may have overlapping communication ranges as shown in FIG. Further, these two wireless communication networks 20 and 30 may perform communication using the same communication method, or may perform communication based on different communication methods. However, it is assumed that the wireless communication networks 20 and 30 are capable of decoding at least information and data transmitted and received between the wireless communication networks 20 and 30 even when communication is performed based on different communication methods. It is said.

  The wireless communication networks 20 and 30 may transmit and receive data via, for example, a public communication network (not shown). At this time, the first NC 21 and the second NC 31 are connected to a public communication network (not shown). Also, the first NC 21 and the second NC 31 can easily find each other's presence via the public communication network (not shown). A public communication network (not shown) also has a database storing each IP address, and the first NC 21 and the second NC 31 can inquire each other's IP address from the database.

  Next, the operation of the interference prevention system 10 between wireless communication networks to which the present invention is applied will be described with reference to FIG. 2, taking as an example the case where data transmission is performed from the wireless terminal DEV2 to the wireless terminal DEV1. In the following example, it is assumed that the wireless terminals DEV1 to DEV6 cannot control the communication level themselves, but can control the communication level under the control of the first NC21 and the second NC31. Further, it is assumed that neither of the wireless terminals DEV3 and DEV4 can transmit accurate position information to the second NC31.

  First, in step S11, the first interference free request signal is transmitted from the wireless terminal DEV2 to the first NC21. The first interference-free request signal is a signal requesting that the area around the wireless terminal DEV1 to which data is communicated be an area free of interference for a certain period of time. Next, the first NC 21 that has received the first interference-free request signal from the wireless terminal DEV2 reads the first interference-free request signal and determines that the communication destination is the wireless terminal DEV1. Then, when the wireless terminal DEV1 actually performs communication, a threshold at which communication interference occurs with the wireless communication network 30 is identified. The threshold value at which the identified communication interference occurs is hereinafter referred to as a coherence level. Further, the first NC 21 may also acquire information such as position information and communication time of the wireless terminal DEV1 as necessary. Further, the first NC 21 is based on the position information and the coherence level in the radio terminal DEV1, and is a range that should be set as an interference free zone when actually communicating with the radio terminal DEV1 (hereinafter, coherence range). May be calculated.

  Next, the process proceeds to step S12, and the first NC 21 transmits a second interference-free request signal to the second NC 31. This second interference-free request signal includes information on the radio terminal DEV1 including the above-described coherence level. The information regarding the wireless terminal DEV1 may include position information, communication time, and information regarding the coherent range described above.

  The second NC 31 that has received the second interference-free request signal can recognize that the periphery of the wireless terminal DEV1 should be in an interference-free zone where no interference occurs by reading the content of the signal. Become.

  Next, the process proceeds to step S13, and the second NC 31 acquires information from each of the wireless terminals DEV3 to DEV6. This information includes the maximum communication level of the wireless terminals DEV3 to DEV6. This maximum communication level means the maximum level among communication levels (including communication voltages) with which the wireless terminals DEV3 to DEV6 can communicate. Further, information acquired from the wireless terminals DEV3 to DEV6 may include location information of each of the wireless terminals DEV3 to DEV6.

  Next, the process proceeds to step S14, and the second NC 31 performs arithmetic processing. In this calculation process, it is determined whether or not the maximum communication level of the wireless terminals DEV3 to DEV6 exceeds the coherence level transmitted from the first NC21. As a result of this determination, if there is at least one wireless terminal DEV3 to DEV6 whose maximum communication level exceeds the coherence level, the process proceeds to step S17. On the other hand, if there is no wireless terminal DEV3 to DEV6 whose maximum communication level exceeds the coherence level, the process does not proceed to step S17.

  In step S14, the determination may be made based on the position information of each of the wireless terminals DEV3 to DEV6. At this time, the second NC 31 has already acquired the position information and coherence range of the wireless terminal DEV1 via the interference-free request signal described above. For this reason, the second NC 31 is in a state where it can know the current position of the wireless terminal DEV1 and its coherence range. The second NC 31 determines whether or not the wireless terminals DEV3 to DEV6 are actually included in the coherent range of the wireless terminal DEV1. As a result, when any one of the wireless terminals DEV3 to DEV6 is included in the coherent range of the wireless terminal DEV1, the maximum communication level described above for the included wireless terminal DEV is the coherent. You may make it determine whether it exceeds a level. For example, in the case of the example in FIG. 1, it is determined that only the wireless terminal DEV3 is in the coherent range. In this case, only the wireless terminal DEV3 determines whether or not the above-described maximum communication level exceeds the coherence level. For the other wireless terminals DEV4 to DEV6, whether or not the maximum communication level exceeds the coherence level. Such a determination may not be performed.

  Thereafter, the process proceeds to step S15, and a signal indicating approval of communication start is transmitted from the second NC 31 to the first NC 21. In step S16, the second NC 31 transmits a signal indicating approval of the communication start to the wireless terminal DEV2. The wireless terminal DEV2 can identify that communication with the wireless terminal DEV1 is permitted by receiving the signal.

  When the process proceeds to step S17, the second NC 31 issues an interference-free command to the radio terminal DEV3 whose maximum communication level exceeds the coherence level. This interference-free command is a command that should be a so-called interference-free zone in which communication interference does not actually occur in the coherent range of the communication destination wireless terminal DEV1. The wireless terminal DEV3 that has received this interference free command lowers its communication level or stops communication. That is, the communication level of the wireless terminal DEV3 is lowered or communication is stopped by the second NC31. As a result, the interference range of the wireless terminal DEV1 can be set to an interference free zone where no interference occurs by reducing the communication level of the wireless terminal DEV3 or stopping the communication.

  For this reason, the wireless terminal DEV2 can communicate with the wireless terminal DEV1 without causing communication interference with the wireless communication network 30.

  Thus, in the interference prevention system 10 between the radio communication networks to which the present invention is applied, the request signal indicating that the radio terminal DEV2 should set the periphery of the communication destination radio terminal DEV1 as an interference free zone in the radio communication network 20. Is transmitted to the first NC 21, the coherence level of the wireless terminal DEV 1 is transmitted to the second NC 31 in the wireless communication network 30 by the first NC 21 that has received the request signal, and the wireless communication network 30 is transmitted by the second NC 31. The maximum communication level is calculated for each wireless terminal DEV, and for the wireless terminal DEV whose calculated maximum communication level exceeds the coherence level transmitted from the first NC 21, the communication level is lowered or the communication is stopped. . Thus, according to the present invention, a plurality of wireless communication networks 20 and 30 can coexist in the same space without interfering with each other, and can be realized with an extremely simple processing flow, thereby reducing the load on the system. It becomes possible.

  The present invention is not limited to the embodiment described above. For example, as shown in FIG. 3, when the second NC 31 cannot acquire the position information for the wireless terminals DEV5 and 6, the wireless terminals DEV5 and 6 that cannot acquire the position information can be taken. Of the positions, the position closest to the wireless terminal DEV1 may be assumed. In the example of FIG. 3, even if the wireless terminal DEV5 is in a position surrounded by a dotted line, the worst case is assumed and it is assumed that the wireless terminal DEV5 is closest to the wireless terminal DEV1 and is surrounded by a solid line. Further, even if the wireless terminal DEV6 is located at a position surrounded by a dotted line, the worst case is assumed and it is assumed that the wireless terminal DEV6 is located closest to the wireless terminal DEV1 and surrounded by a solid line.

  As a result, the coherence range of the wireless terminal DEV1 does not include the wireless terminal DEV5 but includes the wireless terminal DEV6. As a result, for the wireless terminal DEV6, the above-described interference-free command is transmitted from the second NC 31, and the communication level is lowered or the communication is stopped. In this way, it is possible to determine whether or not the wireless terminal DEV from which the second NC 31 cannot acquire position information is also in the coherent range.

10 Interference prevention system 20, 30 Wireless communication network 21 First NC
31 2nd NC
DEV wireless terminal

Claims (6)

In an interference prevention system between wireless communication networks for preventing mutual communication interference when a first wireless communication network and a second wireless communication network each having a wireless terminal and a communication control device exist in the same space,
In the first wireless communication network, the wireless terminal A transmits a request signal to the first communication control device that the area around the wireless terminal B that is the communication destination should be an interference free zone,
The first communication control apparatus that has received the request signal sets a threshold value (hereinafter referred to as a coherence level) at which the radio terminal B determines that communication interference has occurred in the second radio communication network. 2 to the communication control device,
The second communication control apparatus calculates the maximum value of the transmission level of each wireless terminal (hereinafter referred to as the maximum communication level ) for each wireless terminal in the second wireless communication network, and calculates the calculated maximum communication level. For a wireless terminal exceeding the coherence level transmitted from the first communication control device, the communication level is lowered or the communication is stopped. The first communication control device that has received the request signal transmits the position information of the wireless terminal B to the second communication control device in the second wireless communication network,
The second communication control device identifies a coherent range of the wireless terminal B based on the position information of the wireless terminal B, and acquires the position information from each wireless terminal in the second wireless communication network. And determining whether or not the acquired position information is within the identified coherence range,
Control that lowers the communication level or stops communication for a wireless terminal that is determined to fall within the coherent range and whose calculated maximum communication level exceeds the coherent level transmitted from the first communication control device interference prevention system between the wireless communication network of claim 1, wherein the performing. When the second communication control device cannot acquire the position information of the wireless terminal in the second wireless communication network, the position of the wireless terminal that cannot acquire the position information is 3. The interference prevention system between wireless communication networks according to claim 2, wherein it is determined whether or not the wireless terminal B falls within the identified coherence range on the assumption that the position is closest to the wireless terminal B. 4. In the interference prevention method between wireless communication networks for preventing mutual communication interference when a first wireless communication network and a second wireless communication network each having a wireless terminal and a communication control device exist in the same space,
In the first wireless communication network, the wireless terminal A transmits a request signal to the first communication control device that the area around the wireless terminal B that is the communication destination should be an interference free zone,
A threshold value (hereinafter referred to as a coherence level) that is determined by the first communication control apparatus that has received the request signal that communication interference has occurred in the wireless terminal B is referred to as a second threshold in the second wireless communication network. To the communication control device of
The second communication control apparatus calculates the maximum value of the transmission level of each wireless terminal (hereinafter referred to as the maximum communication level ) for each wireless terminal in the second wireless communication network, and the calculated maximum communication level is An interference prevention method between wireless communication networks, characterized in that, for wireless terminals exceeding the coherence level transmitted from the first communication control device, the communication level is lowered or communication is stopped. The first communication control device that has received the request signal transmits the location information of the wireless terminal B to the second communication control device in the second wireless communication network,
Based on the position information of the wireless terminal B, the coherent range of the wireless terminal B is identified by the second communication control device, and the position information is acquired from each wireless terminal in the second wireless communication network. Then, it is determined whether or not the acquired position information falls within the identified coherence range, and is determined to be within the coherence range, and the calculated maximum communication level is transmitted from the first communication control device. 5. The method of preventing interference between wireless communication networks according to claim 4, wherein control is performed to lower the communication level or stop communication for a wireless terminal that exceeds the allowed interference level . If the position information of the wireless terminal in the second wireless communication network cannot be acquired by the second communication control device, among the possible positions of the wireless terminal that cannot acquire the position information 6. The method of preventing interference between wireless communication networks according to claim 5, wherein it is determined whether or not the wireless terminal B falls within the identified coherence range on the assumption that the position is closest to the wireless terminal B.

Images