JP2010278670A - Cell site design device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a cell site design device capable of efficiently deciding the installation positions of base stations by accurately calculating RSSI. <P>SOLUTION: The cell site design device 1 includes a reception power measurement I/F section 2 for acquiring reception power information, namely, a reception power measurement result from a radio device under utilization, each time the positional information of own device is inputted from the outside; a communication quality determining section 3 for calculating the RSSI, based on the reception power information, correcting the calculated RSSI by a method corresponding to the radio device under utilization to generate the RSSI after correction, and relating the calculated RSSI to the position information for storing in a storage section 8; and a determined result output I/F section 4 for generating a communication quality determination result, in areas indicating a communication-enabled area and an communication-disabled area within a station target area, based on the RSSI and position information stored in the storage section 8 and map information of the station target area, for the in-area reception of instruction from a user. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a station placement design apparatus that determines an arrangement (placement) when installing a base station of a wireless LAN.

  In conventional wireless LAN base station installation (station placement), the temporary position of the placement station is first determined, the base station is placed at each temporary determination position, and then the RSSI (Received Signal Strength Indicator) value is measured. The final positioning of the base station was performed according to the measurement result (for example, see Non-Patent Documents 1 and 2 below).

  Here, in the following Non-Patent Document 3 in which the wireless LAN standard is described, in the case of 2.4 GHz band direct spreading, the received RF power in the direct spreading PHY is measured, and the RSSI is used using this result. It is stipulated to obtain a value. However, the specific measurement method of the RSSI value is not specified in Non-Patent Document 3, and although the RSSI value level is specified in 8 bits, the RSSI value around 1 bit is also specified. It has not been.

  In addition, Non-Patent Document 3 specifies that the power of the PLCP preamble is measured in the case of OFDM (Orthogonal Frequency Division Multiplexing) in the 5 GHz band, and its value is in the range of 0 to RSSI Maximum. The value of RSSI Maximum is not specified.

“AirMagnet Survey Pro / Standard 6.0 802.11a / b / g wireless LAN site survey dedicated tool”, 2009, Internet <http://www.toyo.co.jp/airmagnet/d_airmagnet_sv.html> “Ekahau Site Survey”, 2009, Internet <http://www.marubeni-sys.com/network/ekahau/ess-lan.html> “IEEE Std 802.11.-2007, Part 11 Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications”

  When determining the installation position of a wireless LAN base station based on the non-patent document 3 using the above device (the device described in the non-patent document 1 or 2), the base station is temporarily installed, The device collects the RSSI measurement results by the general-purpose wireless LAN device (terminal station), and determines the final installation position of the base station based on the collected RSSI. However, as described above, since the uncertain part is included in the standard, the vendor of each wireless LAN device (terminal station) decides the RSSI measurement method independently, and the RSSI value per 1 bit is different for each vendor. Therefore, when RSSI measurement results are collected using a device other than the specific wireless LAN device assumed in advance, it is necessary to perform some device-specific correction on the acquired RSSI measurement value. For example, when the wireless LAN device to be used outputs an RSSI value higher than the RSSI measurement result by the assumed device, if the final installation position is determined using the output RSSI value as it is, a specific location Thus, sufficient communication quality cannot be obtained. On the other hand, when the wireless LAN device to be used outputs an RSSI value lower than the RSSI measurement result by the assumed device, if the final installation position is determined using the output RSSI value as it is, it is more than necessary. A large number of base stations will be installed, and efficient placement will not be possible.

  In addition, when voice data is passed over a wireless LAN, real-time performance is required, so even if the RSSI value is satisfied, the quality may deteriorate with the execution of the handover.

  The present invention has been made in view of the above, and is a case of performing placement (determining the installation position of a base station) using a wireless LAN device that measures RSSI by a method that is not assumed in advance. However, the desired communication quality can be obtained at an arbitrary position in the area where the base station is installed, and the base station is not installed more densely than necessary. It is an object of the present invention to provide a station design apparatus that can calculate with high accuracy and can efficiently determine the installation position of a base station.

  In order to solve the above-described problems and achieve the object, the present invention uses a reception power measurement result of a wireless signal in any one of a plurality of usable wireless devices, and a wireless LAN base. This is a station design device that generates an in-area communication quality judgment result to be referred to when determining the station installation position, and receives the received power from the wireless device being used each time the position information of the own device is input from the outside. Received power information acquisition means for acquiring received power information as a measurement result, calculate RSSI based on the received power information, and further correct the calculated RSSI by a method according to the wireless device being used. Communication quality information generating means for generating a corrected RSSI and storing it in the storage unit in association with the location information, and when receiving an instruction from the user, the RSSI and the RSSI stored in the storage unit An area determination means for generating an in-area communication quality determination result indicating a communicable area and an incommunicable area in the placement target area based on the position information and the map information of the placement target area. It is characterized by.

  According to the present invention, the station placement design apparatus obtains the received power information measured by the radio apparatus, calculates the RSSI value, and corrects this by a different method for each radio apparatus to generate a corrected RSSI value. In addition, when an instruction is received from the user, an in-area communication quality determination result is generated based on the stored RSSI value after correction and the position information. Therefore, it is possible to improve the RSSI calculation accuracy when a wireless LAN device that measures RSSI by a method that is not assumed in advance is used as the wireless device. As a result, the user can obtain desired communication quality at an arbitrary position in the installation target area where the base station is installed, and the base station is not installed more densely than necessary. The effect is that the installation position of a typical base station can be determined.

FIG. 1 is a diagram showing a configuration example of a first embodiment of a station placement design apparatus according to the present invention. FIG. 2 is a diagram showing another configuration example of the station location design apparatus according to the present invention. FIG. 3 is a flowchart illustrating an operation example of the communication quality determination unit.

  Hereinafter, an embodiment of a station placement design apparatus according to the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration example of a first embodiment of a station placement design apparatus according to the present invention. 1 includes a received power measurement I / F (interface) unit 2, a communication quality determination unit 3, a determination result output I / F unit 4, a measurement position input I / F unit 5, a parameter input. An I / F unit 6, a map information input I / F unit 7, and a storage unit 8, and the user determines the installation position of the base station using the reception power measurement result of the radio signal measured by the external radio device 100. Information to be referred to when making a decision is generated.

  In the in-station design device 1, the received power measurement I / F unit 2 (corresponding to the received power information acquisition unit) provides a function of connecting to a wireless device 100 such as an external wireless LAN, and the wireless power measured by the wireless device 100. The received power of the signal is acquired at a predetermined timing. Although FIG. 1 shows a configuration example in which the wireless device 100 is placed outside the station placement design apparatus, a configuration in which the radio apparatus 100 is placed in the station placement design apparatus as shown in FIG. Regardless of which configuration is adopted, the operation of each component of the station placement design apparatus is the same.

  1, the interface (I / F) with the wireless device 100 is USB, SDIO, PCI, PCICIA, etc., and the H / W ( Hardware) Adopt a configuration according to the shape. When a plurality of I / Fs are provided, the received power is acquired via the I / F to which the wireless device 100 is connected.

  The communication quality determination unit 3 (corresponding to the communication quality information generation unit) receives the reception power measurement result and the parameter input I / F unit 6 in the wireless device 100 received via the reception power measurement I / F unit 2 from the outside. Based on the parameters held in the storage unit 8, the communication quality is calculated.

  In addition, this Embodiment demonstrates the example in case the communication quality determination part 3 calculates RSSI as communication quality. A case where communication quality other than RSSI is calculated will be described in Embodiment 2.

  The determination result output I / F unit 4 (corresponding to the area determination unit) stores the output from the communication quality determination unit 3 (the calculated RSSI value and the like will be described in detail later) in response to a request from the user. And the information received from the outside via the measurement position input I / F unit 5, the parameter input I / F unit 6 or the map information input I / F unit 7 (details will be described later) Based on the above, an in-area communication quality determination result (details will be described later), which is reference data when determining the installation position of the base station in the installation target area, is generated and output.

  The measurement position input I / F unit 5 provides an interface for acquiring position information from the outside by allowing the user to input position information, for example. When the position information is acquired, the position information is stored in the storage unit 8 after being associated with the determination result (calculated RSSI value) in the communication quality determination unit 3 at that time. As an example of the interface, a configuration in which position information is input using a mouse or a touch pen that inputs to a liquid crystal screen is conceivable. In addition, the position information is periodically acquired using a GPS (Global Positioning System) or the like, and the position information is stored in the storage unit 8 in association with the determination result in the communication quality determination unit 3 every time the position information is acquired. May be adopted.

  The parameter input I / F unit 6 provides an interface for inputting predetermined initial parameters, and the input information (initial parameters) is stored in the storage unit 8. The initial parameter is information that instructs the operation of the station placement design apparatus. Examples of the interface include a configuration in which a keyboard or the like is connected to input a specified value, or a configuration in which a serial cable interface such as RS233C is provided and input from a PC connected via the interface. Specific examples of input information (initial parameters) include parameters such as meter distance information on the map, wireless delay and packet loss rate used in the communication quality determination unit 3, and the base station area range (communication range). There is a setting of information used for determination (designation of whether to perform determination using an RSSI value or a voice quality value).

  The map information input I / F unit 7 provides an interface for inputting map information, acquires layout information of the area to be measured (placement target area), map information, and the like as input information and stores them in the storage unit 8. To do. Examples of interfaces include a scanner and a map capture format in a file format, map information that has been converted to an image format file such as jpeg, and map information that has been converted to a text file such as xls from a PC Configuration is conceivable.

  The storage unit 8 is realized by, for example, a memory or an HDD, and stores information received from each unit in the station location design apparatus 1.

  Next, an operation example of the station placement design apparatus 1 according to the present embodiment will be described. The reception power measurement I / F unit 2 acquires information on the reception power of the radio signal measured by the radio apparatus 100 periodically or when receiving an instruction from the user. In addition, when the received power measurement I / F unit 2 acquires the received power information, it passes it to the communication quality determination unit 3. The received power measurement I / F unit 2 refers to parameters stored in the storage unit 8 (various parameters included in the initial parameters received by the parameter input I / F unit 6 from the outside) when performing this operation. Then, the operation according to the parameter value is executed. For example, a parameter indicating an operation mode indicating whether reception power information is acquired periodically or when an instruction is received from a user, a parameter indicating an acquisition operation execution cycle when reception power information is periodically acquired, etc. Execute the operation according to

  Upon receiving the received power information from the received power measurement I / F unit 2, the communication quality determination unit 3 calculates an RSSI value based on the received power information and a parameter (initial parameter) stored in the storage unit 8. . The calculation result is stored in the storage unit 8 together with information on the measurement position input via the measurement position input I / F unit 5. If the same measurement position information as the measurement position information to be stored has been stored in the storage unit 8 in association with the RSSI value, an operation designated in advance is executed. For example, replace previously stored information with newly calculated information, calculate an average value of previously stored information (previously calculated information) and newly calculated information, and replace it with Perform operations such as

  When the determination result output I / F unit 4 receives an instruction to output the determination result from the user, the determination result output I / F unit 4 is connected to the area based on the measurement position information stored in the storage unit 8, the RSSI value associated therewith, and the map information. Generate and output a communication quality determination result. Specifically, each position on the map indicated by the map information of the determination target area (placement target area) (each position corresponding to each stored measurement position information) is stored in association with each position. Plotting based on the RSSI value being performed is performed, map information indicating communication quality (RSSI value) at each position in the determination target area is generated, and this is output as an intra-area communication quality determination result.

  Here, in the station placement design apparatus 1 according to the present embodiment, a threshold value (first value) for determining whether or not communication requiring low real-time performance (such as voice) (low delay communication) can be realized based on the RSSI value. And a threshold value (second threshold value) for determining whether or not communication that does not require real-time performance is feasible based on the RSSI value (second threshold value) is determined in advance. And stored in the storage unit 8 or the like. Note that a relationship of “second threshold value <first threshold value” is established, and these threshold values correspond to the RSSI values for determining the area range of the base station described above. When the determination result output I / F unit 4 plots the RSSI value on the map of the determination target area, the place where the RSSI value reaches the first threshold value (referred to as a voice communication possible area for convenience). ), A place where the RSSI value (or communication quality information) is between the second threshold value and the first threshold value (referred to as a non-voice communication possible area), and other places (a communication impossible area and And plot them in different ways. That is, the determination result output I / F unit 4 plots each of the three areas divided according to the RSSI value using, for example, different colors, and outputs the result as an intra-area communication quality determination result.

  Select whether to interpolate between plots by changing the setting of a specific parameter in the initial parameter so that the plot can be displayed as a dot or a line. A possible configuration may be used. As an interpolation method, for example, free space attenuation (square law) is used. In addition, if there are obstacles (shields) such as walls and desks in the judgment target area, information such as the position and size is obtained in advance (input by the user), and attenuation is taken into account Then, interpolation may be performed.

  The determination result output I / F unit 4 performs output by paper using a printer, output by a file such as jpe or xls, output (display) to a display panel, etc., when outputting the communication quality determination result in the area. .

  Note that the station placement design apparatus 1 of the present embodiment shown in FIG. 1 and FIG. 2 is either a hardware measuring device, software on a PC, or software linked to hardware added to a PC. It may be realized with.

  It continues and the calculation method of RSSI in the communication quality determination part 3 is demonstrated. When the communication quality determination unit 3 is configured to calculate the RSSI value as the communication quality, the station location design device 1 sets the RSSI correction value and the wireless LAN for each of a plurality of wireless LAN terminals connectable as the wireless device 100. The terminal name of the terminal is acquired via the parameter input I / F unit 6 and stored in the storage unit 8. The RSSI correction value is calculated in advance based on, for example, each RSSI value measured in the same environment (same position) using all connectable wireless LAN terminals as the wireless device 100. Based on the difference between the RSSI calculation result when one of the connectable wireless LAN terminals is used as a reference terminal and this reference terminal is used and the RSSI value when a wireless LAN terminal other than the reference terminal is used What is necessary is just to calculate the RSSI correction value of each wireless LAN terminal.

  Then, when calculating the RSSI value, the communication quality determination unit 3 calculates the RSSI value using the received power information received from the received power measurement I / F unit 2, and then connects the RSSI value as the wireless device 100. It corrects using the correction value corresponding to the wireless LAN terminal currently performed, and outputs it as a final RSSI value (RSSI value after correction). Hereinafter, the calculation operation of the RSSI value will be described in more detail with reference to FIG. FIG. 3 is a flowchart illustrating an operation example of the communication quality determination unit 3. For convenience, processing in parts other than the communication quality determination unit 3 is also shown.

  When the measurement position input I / F unit 5 detects that the measurement position information has been input (step S10), the communication quality determination unit 3 is instructed to measure the communication quality, and the received communication. The quality determination unit 3 calculates an RSSI value based on the received power information received from the received power measurement I / F unit 2 and obtains basic information of the wireless LAN terminal connected as the wireless device 100 from the storage unit 8. (Step S11). The basic information includes a terminal name, a correction value used when correcting RSSI, and the like.

  And the communication quality determination part 3 judges whether RSSI value needs to be corrected based on the basic information acquired at step S11 (step S12), and when correction is required (step S12, Yes). The RSSI correction process is executed using the RSSI correction value included in the basic information acquired in step S11 (step S13). On the other hand, when the correction is unnecessary (No at Step S12), the process proceeds to Step S14. Whether the RSSI value needs to be corrected is determined, for example, based on the terminal name whether the wireless LAN terminal connected as the wireless device 100 is a reference terminal that does not need correction processing. Not implemented (determining that correction processing is unnecessary).

  Furthermore, the communication quality determination unit 3 determines whether or not it is necessary to perform the voice quality conversion process (step S14). If necessary (step S14, Yes), the RSSI obtained by executing step S12. Value or the corrected RSSI value obtained by executing Step S13 is converted into voice quality information (Step S16), and the obtained voice quality information is output in association with the measurement position information obtained in Step S10, that is, Store in the storage unit 8 (step S17). On the other hand, if it is not necessary to perform the voice quality conversion process (No in step S14), the RSSI value obtained by executing step S12 or the corrected RSSI value obtained by executing step S13 is used as the above step S10. And stored in the storage unit 8 in association with the measurement position information acquired in step S15. Whether or not the voice quality conversion process needs to be performed is determined according to the instructions from the user, and if the voice quality conversion process is set to be performed on the menu screen for operation specification, etc. Judge that it is necessary. Details of the voice quality conversion process performed in step S16 will be described in the second embodiment.

  As described above, the station designing apparatus according to the present embodiment obtains information on the received power of the radio signal transmitted from the base station measured by the radio device, and calculates the RSSI value using the obtained received power information. Then, this is corrected by a different method for each wireless device (corrected using different correction values) to generate a corrected RSSI value. Further, the RSSI value after correction is stored in association with the position information of the device itself, and each position in the placement target area is sounded based on the stored RSSI value and position information after correction. It was decided to belong to any of the communicable area, non-voice communicable area and incommunicable area. Thereby, the calculation precision of the RSSI value used for the determination of an area can be improved. As a result, even when a wireless LAN device (a wireless LAN terminal other than the reference terminal) that measures an RSSI value by a method that is not assumed in advance is used as a wireless device, the user can install a base station. It is possible to obtain a desired communication quality at an arbitrary position in the target area and to determine an efficient base station installation position without installing base stations more densely than necessary.

  Note that a wireless LAN that can be connected as the wireless device 100 is also assumed in the case where the installation position of a base station is determined for the purpose of mainly providing a communication (low-delay communication) service that requires real-time performance such as voice. Of the terminals, the wireless LAN terminal with the lowest measurement result of the RSSI value under the same conditions (same environment) may be used as the reference terminal for correction. In other words, a configuration is adopted in which the user can select whether the station design is intended to provide a low-delay communication service, and the communication quality (RSSI value) is corrected by a method according to the selection result by the user. May be. The wireless LAN terminal having the lowest RSSI value measurement result under the same condition is corrected as a reference terminal because the wireless LAN terminal determines that the communication quality has deteriorated from the RSSI value measurement result and performs handover. This is to suppress the frequency of execution, and this can prevent the quality of voice communication from deteriorating with the execution of the handover.

Embodiment 2. FIG.
Next, in the station location design apparatus 1 described in the first embodiment, the operation in which the communication quality determination unit 3 converts the RSSI value into voice quality information, that is, the operation executed in step S16 in FIG. 3 will be described.

  When the communication quality determination unit 3 executes a process of converting the RSSI value into voice quality information (voice quality conversion process), the station location design apparatus 1 uses the document “ITU-T Rec. G107 E-model” <http: / The parameters specified in /www.itu.int/ITU-T/studygroups/com12/emodelv1/tut.htm> are acquired via the parameter input I / F unit 6 and stored in the storage unit 8 as initial parameters. deep. Hereinafter, the voice quality conversion process will be described.

When the voice quality conversion process is executed, the communication quality determination unit 3 uses the R-value defined in the above document based on the E-modl calculation formula shown by the following formula in step S16 shown in FIG. calculate. And R value is output as audio | voice quality (equivalent to the process of step S17 linked | related with measurement position information and stored in the memory | storage part 8).
R = Ro-Is-Id-Ie, eff + A

  Here, “Ro” is the total quality calculated considering only degradation due to line noise, transmitter and receiver indoor noise, subscriber line noise, etc., and “Is” is OLR, side noise. And qdu (note that qdu is a quantization distortion unit of PCM coding including ADPCM), and “Id” is a degradation due to a transmitter echo, a receiver echo, and a delay time. “Ie, eff” is a degradation due to low bit rate encoding, packet loss, and the like. “A” indicates a complementary value for convenience such as mobile communication. These are composed of 23 parameters. Of these, parameters related to radio are “Ta” (end-to-end one-way delay time, unit is msec) and “Ppl” (packet loss rate, unit is %). Therefore, the communication quality determination unit 3 performs the following correction using these two parameters. However, radio is considered for the packet loss rate and the end-to-end one-way delay time. That is, the packet loss rate is a packet loss rate in the wireless section, and an actual measurement value or a simulation value calculated by another system is input as the packet loss rate. Alternatively, the packet length defined as the received power is input via the parameter input I / F unit 6 and the communication quality determination unit 3 calculates the packet loss rate. For example, since the non-patent document 3 describes the received power at a value of PER = 10% at the time of 1000 byte length data transmission, the packet loss rate (PER) is calculated using this.

  In addition, the end-to-end one-way delay time applies only the radio delay, and the sum of the transmission delay at the time of maximum capacity, the transmission timing waiting time (binary backoff time), the retransmission time due to packet collision, etc. is obtained. It should be noted that the end-to-end one-way delay time is input from the parameter input I / F unit 6 as it is and is stored in the storage unit 8 as measured values or simulation values calculated by other systems. Alternatively, the above-described transmission delay, transmission timing waiting time, retransmission time due to packet collision, maximum number of radio apparatuses accommodated in the base station, etc. are input from the parameter input I / F unit 6 and stored in the storage unit 8, and the values are stored. The communication quality determination unit 3 uses the calculation.

  Note that the end-to-end one-way delay time is considered only for radio, but when there is much communication with a specific base, it may be calculated in consideration of a wired delay between the specific bases. In this embodiment, the R value is calculated, but it may be converted into a MOS (Mean Opinion Score) value and output. In this case, Annex. Follow the description in B.

  The operation of the measurement result output I / F unit 4 according to the present embodiment (the operation when the communication quality determination unit 3 executes the voice quality conversion process) is that the information to be used is the voice quality and measurement from the RSSI value and the measurement position information. Except for the point that the position information is changed, the second embodiment is the same as the first embodiment.

  Thus, in addition to the functions of the station placement design apparatus of the first embodiment, the station placement design apparatus of the present embodiment uses the RSSI value obtained by the procedure shown in the first embodiment as voice quality information. Executing the conversion process, and determining, based on the voice quality information, which area in the placement target area belongs to the voice communication available area, the non-voice communication available area, and the communication disabled area. did. As a result, a station placement design that evaluates not by the RSSI value but by voice quality is realized, and an effect of facilitating the station placement design in an easy-to-understand manner can be expected even for a user who does not know the radio.

  As described above, the station placement design apparatus according to the present invention is useful when generating an in-area communication quality determination result that is information to be referred to when determining a base station installation position of a wireless LAN. This is suitable for a station design apparatus capable of determining an area based on voice quality in addition to the use of.

DESCRIPTION OF SYMBOLS 1 Station location design apparatus 2 Received power measurement I / F part 3 Communication quality judgment part 4 Judgment result output I / F part 5 Measurement position input I / F part 6 Parameter input I / F part 7 Map information input I / F part 8 Storage unit 100 Wireless device

Claims (6)

Generates in-area communication quality judgment results to be used when determining the location of a wireless LAN base station using the reception power measurement results of radio signals in any one of a plurality of available radio devices A station location design device,
Received power information acquisition means for acquiring received power information that is a received power measurement result from a wireless device that is used every time position information of the own device is input from the outside,
An RSSI is calculated based on the received power information, and the calculated RSSI is corrected by a method according to a wireless device used to generate a corrected RSSI, which is associated with the position information in the storage unit. Means for generating communication quality information to be stored;
When receiving an instruction from the user, based on the RSSI and the position information stored in the storage unit and the map information of the station target area, the communicable area and the incommunicable area in the target station area An area determination means for generating an in-area communication quality determination result indicating:
A station location design apparatus comprising:   When the wireless device being used is a reference terminal that is determined in advance, the communication quality information generation means associates with the position information without executing correction processing for the calculated RSSI in the storage unit. The station placement design apparatus according to claim 1, wherein the station placement design apparatus is stored. Generates in-area communication quality judgment results to be used when determining the location of a wireless LAN base station using the reception power measurement results of radio signals in any one of a plurality of available radio devices A station location design device,
Received power information acquisition means for acquiring received power information that is a received power measurement result from a wireless device that is used every time position information of the own device is input from the outside,
Communication quality information generating means for calculating voice quality based on the received power information and storing the voice quality in association with the position information;
When an instruction is received from the user, communication with the communicable area in the installation target area is impossible based on the voice quality and position information stored in the storage unit and the map information of the installation target area Area determination means for generating an in-area communication quality determination result indicating an area;
A station location design apparatus comprising:   4. The station placement design apparatus according to claim 3, wherein the communication quality information generating unit first calculates RSSI based on the received power information, and calculates voice quality based on the calculated RSSI.   The communication quality information generating unit further corrects the calculated RSSI by a method according to a wireless device being used, and calculates voice quality using the obtained RSSI after correction. Item 5. The station design apparatus according to Item 4.   The area determination means classifies each position in the communicable area into two positions that allow realization of communication that requires real-time performance, and a position where realization is impossible, and intra-area communication including the classification result The station placement design apparatus according to any one of claims 1 to 5, wherein a quality determination result is generated.

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