JP3632912B2 - Wireless LAN base station position determining method, wireless component and program used for implementing the method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wireless LAN (Local Area Network) wireless base station position determination method, and more particularly, to a method for optimizing an antenna installation location of a wireless base station.
[0002]
[Prior art]
In the local wireless LAN system, the installation location of the wireless base station and the wireless mobile terminal is very important for efficient wireless communication. In other words, on-site fixtures, partitions, human bodies, etc. block the radio wave arrival path and radio waves cannot reach the base station, and also due to fading that occurs when delayed waves such as reflected waves and diffracted waves from objects interfere with signal waves There is a problem that the communication quality deteriorates and the signal error rate increases. This tends to be stronger as the frequency becomes higher and wider.
[0003]
In order to solve this problem, there is a technique for simulating a campus environment on a computer. According to this technology, it is possible to predict the radio wave propagation characteristics in the campus in advance by incorporating the position of the object in the campus, the reflection characteristics of the wall surface, the antenna characteristics, and the like. From this radio wave propagation characteristic, if a point with a good transmission / reception state is selected, an optimal base station installation location can be determined.
Conventionally, a technique described in Japanese Patent Application Laid-Open No. 5-75319 is known as a technique related to installation of a base station antenna.
Japanese Patent Application Laid-Open No. 5-75319 relates to a test of a transmission / reception function of a radio base station apparatus. A test antenna composed of at least one minute antenna is provided inside the base station antenna configuration of the radio base station. In addition, by providing a pass-type resistance attenuator between the test antenna and the test apparatus, deterioration of impedance characteristics due to the use of the minute antenna is suppressed. As a result, it is possible to incorporate the test antenna device and economically measure the propagation loss without increasing the size of the base station antenna device.
[0004]
[Problems to be solved by the invention]
In-house wireless LAN systems are used not only at large scales such as offices and factories, but also at home and other individual levels.
However, the above-described conventional radio wave propagation simulation is mainly intended for commercial use and is expensive to purchase at home. In addition, since the conventional radio wave propagation simulation calculates the presence of reflected waves, it is necessary to input all floor plan information such as the position of the object and the material of the wall surface.
Also, the reception state is not always good even if the location is predicted to be optimal in the conventional radio wave propagation simulation. In the actual environment, unpredictable environmental changes such as movement of people occur. In addition, the simulation and the actual environment do not always match, such as a change in the transmission power of the antenna and a mismatch between the base station installation direction and the radio wave polarization direction. Also, if the base station antenna has to be moved for some reason from the location optimized in the simulation, the above operation must be repeated.
[0005]
On the other hand, the technique described in Japanese Patent Laid-Open No. 5-75319 requires power supply to the base station antenna device and the test antenna device. For this reason, wiring is required for installation, and when it becomes necessary to move the base station while searching for an optimal base station installation location, there is a problem that wiring of the power supply must be newly re-executed.
[0006]
The present invention has been made to solve such a problem, and an object of the present invention is to determine where the wireless mobile terminal can be optimally communicated without the need for external power supply. It is an object to provide a wireless LAN base station determination method capable of easily evaluating in an environment and determining an appropriate position of a wireless base station, a wireless component used in the implementation of the method, and a computer program.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a method of the present invention is a method for determining an appropriate position of a wireless base station in a wireless LAN using a wireless component with a built-in battery capable of transmitting and receiving data in the same wireless frequency band as the wireless base station. The radio mobile terminal transmits a question signal in the radio frequency band in a state where the radio mobile terminal is placed at a desired position within the movement range and the radio component is placed at a candidate position of the radio base station. Then, the presence / absence of a response signal from the wireless component to the interrogation signal is monitored, and it is determined whether the candidate position is an appropriate position of the wireless base station according to the content of the response.
Further, as the interrogation signal, an interrogation signal including identification information unique to the radio mobile terminal is transmitted, and as the response signal, the radio mobile terminal that transmitted the interrogation signal, the identification information of the radio component itself, the received interrogation signal A response signal including a reception level is returned.
[0008]
A wireless component with a built-in battery that is used to determine the appropriate position of a wireless base station in a wireless LAN, and is transmitted from a desired position within the movement range of the wireless mobile terminal in the same wireless frequency band as the wireless base station. And a response signal including a reception level of the received inquiry signal and the received identification information of the wireless mobile terminal in the radio frequency band.
[0009]
A program that operates in a mobile radio terminal to determine an appropriate position of a radio base station in a wireless LAN using a battery built-in radio component that can transmit and receive data in the same radio frequency band as the radio base station. , Transmitting the interrogation signal to the radio component placed at the candidate position of the radio base station in the radio frequency band, monitoring the response signal from the radio component to the interrogation signal, and depending on the content of the response, the candidate It includes a process of evaluating whether the position is an appropriate position of the radio base station.
The mobile terminal device of the present invention is a device that determines an appropriate position of a wireless base station in a wireless LAN using a battery built-in wireless component capable of transmitting and receiving data in the same radio frequency band as the wireless base station, Identification information of the wireless mobile terminal that transmits the interrogation signal in the radio frequency band with the radio component placed at the candidate position of the radio base station and transmits the interrogation signal from the radio component for the interrogation signal, the radio component itself It is characterized by comprising a display means for receiving a response signal including the identification information and the reception level of the received question signal and displaying the content of the response.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment for carrying out the present invention will be specifically described with reference to the drawings.
FIG. 1 is a conceptual diagram showing an embodiment of the present invention. The present invention includes a wireless LAN base station 11, a wireless tag (wireless component) 12 in which at least one wireless LAN base station 11 is to be installed, and a plurality of wireless LAN terminals (wireless mobile terminals). ) 13 and an antenna device 14 for the wireless LAN terminal 13 to perform wireless LAN communication.
It is assumed that the wireless LAN terminals 13 are not connected so as to be able to communicate by wire, and the base station 11 is in a state before being wired and is not supplied with power from the outside.
[0011]
The wireless tag 12 can transmit and receive radio waves in the same frequency band as the wireless LAN. The wireless tag 12 has a built-in battery and does not require external power supply. It is assumed that the wireless tag 12 functions equally whether used alone or incorporated in the wireless LAN base station 11.
A tag ID is recorded in advance in the LSI memory of the wireless tag 12. Each wireless LAN terminal 13 uses an ID recorded in the antenna device 14 as a terminal ID. It is assumed that each ID is unique identification information and cannot be changed.
[0012]
FIG. 2 is a diagram for explaining the operation of the present invention under the configuration of FIG. The wireless tag 12 includes a radio wave transmitting / receiving antenna device 121 and an arithmetic processing device 122, and the arithmetic processing device 122 has a signal transmission / reception processing 123.
The wireless LAN terminal 13 includes a radio transmission / reception antenna device 131 and an arithmetic processing device 132, and the arithmetic processing device 132 has a signal transmission / reception processing 133 and a terminal position evaluation program 134.
The interrogation signal 210 can be transmitted from the radio wave transmission / reception antenna device 131 of the wireless LAN terminal 13, and the response signal 211 can be transmitted from the radio wave transmission / reception antenna device 121 of the wireless tag 12. These signals 210 and 211 use the same frequency band as the frequency used in the wireless LAN.
[0013]
Next, the procedure for evaluating the installation location will be described with reference to FIG.
First, as a preparation for evaluating the installation location, the wireless tag 12 alone or the wireless LAN base station 11 incorporating the wireless tag 12 is placed at a planned installation location (candidate position). Further, the wireless LAN terminal 13 is placed at a planned installation location within the moving range. The wireless tag unit 12 and the wireless LAN base station 11 incorporating the wireless tag 12 are not wired with a power supply, and can be freely moved. Thereby, it is possible to perform evaluation at various points while freely moving the wireless tag 12 and the wireless LAN terminal 13.
With the wireless tag unit 12 and the wireless LAN base station 11 incorporating the wireless tag 12 placed at the candidate position and the wireless LAN terminal placed at the planned installation location, the arithmetic processing units 132 and 122 are activated, and signal transmission / reception is performed. The process 133, the terminal position evaluation program 134, and the signal transmission / reception process 123 are executed.
[0014]
Then, the signal transmission / reception processing 133 of the wireless LAN terminal 13 transmits the interrogation signal 210 on the frequency band used in the wireless LAN uplink. The wireless tag 12 that has received the interrogation signal 210 generates a response signal 211 corresponding to the interrogation signal 210 in the signal transmission / reception process 123 and transmits it on a frequency band used in the downlink of the wireless LAN.
The wireless LAN terminal 13 that has received the response signal 211 evaluates the communication state based on the content of the response signal 211 and the transmission / reception state. If the response signal 211 cannot be received due to the environment in which the wireless tag 12 is placed, the current position of the wireless tag 12 is evaluated as an inappropriate installation position based on the result that the response signal 211 cannot be received for a certain period of time.
[0015]
Next, the contents of each signal will be described.
FIG. 3 shows an example of the contents of the question signal 210 and the response signal 211. 4A shows the contents of the question signal 210, and FIG. The interrogation signal 210 shown in (a) includes a synchronization signal for synchronizing communication, a terminal identification ID for identifying the wireless LAN terminal 13 that transmitted the interrogation signal, and error correction for detecting and correcting the above-described information error. A sign is included.
The response signal 211 shown in (b) includes a synchronization signal for synchronizing communication, a terminal identification ID for identifying the wireless LAN terminal 13 that transmitted the inquiry signal 210, and the wireless tag 12 that transmitted the response signal 211. A wireless tag identification ID to be identified, a reception level of a radio wave received by the wireless tag 12, an error correction code for detecting and correcting the above-described information error, and a BER (signal error rate) determination code are included. The same BER determination code is recorded in the wireless tag 12 and the wireless LAN terminal 13 in advance, and is transmitted from the wireless tag 12 and compared with the code recorded in the wireless LAN terminal 13 to obtain a communication code. Error rate can be measured.
[0016]
Next, the signal transmission / reception process 123 of the wireless tag 12 will be described.
FIG. 4 is a flowchart showing the operation of the wireless tag 12. The wireless tag 12 is always in a state where it can monitor and receive radio waves. When a synchronization signal of the inquiry signal 210 is received from the wireless LAN terminal 13 (step 41), the subsequent terminal identification ID is read. Next, the process proceeds to creation of the response signal 211. The terminal identification ID recorded in the question signal 210, the wireless tag identification ID for identifying the wireless tag 12, the radio wave reception level at the wireless tag 12, the error correction code, and the BER determination recorded in the wireless tag 12 in advance. A code is added as information of the response signal 211 (step 42).
[0017]
Next, the response signal 211 created in step 42 is transmitted, but the wireless tag 12 and the wireless LAN terminal 13 that receives the signal are not always at the same distance, so the transmission level is adjusted. . Specifically, when the reception level of the interrogation signal 210 is low, the transmission level of the response signal 211 is increased so that the wireless LAN terminal 13 can easily receive it (step 43). In this step 43, it is assumed that the actual wireless LAN base station 11 has the same function and there is no deficiency in the BER measurement.
Next, the response signal 211 is transmitted over a predetermined time at the transmission level determined in step 43 (step 44), and the transmission is terminated after the predetermined time has elapsed.
[0018]
Next, the terminal position evaluation program 134 will be described.
FIG. 5 is a flowchart showing an outline of the terminal position evaluation program 134.
The terminal location evaluation program 134 includes a signal transmission / reception process 123. First, the user temporarily installs at least one wireless tag 12 at a place where the base station 11 is planned to be installed. Next, a plurality of wireless LAN terminals 13 to be used are placed at locations where installation is planned. It is assumed that the same program 134 is built in each wireless LAN terminal 13. The wireless tag 12 to be evaluated is selected from each wireless LAN terminal 13 (step 51). A plurality of wireless tags 12 may be selected. The wireless tag identification ID of the wireless tag 12 whose position is evaluated from the selected wireless tag group is set (step 52). Evaluation processing by the signal transmission / reception processing 133 and the terminal position evaluation program 134 is performed on the wireless tag identification ID (step 53).
[0019]
If there is a block or movement of a person at the time of signal transmission / reception, the transmission state cannot be determined by only transmission / reception once. Therefore, here, signal transmission / reception processing 133 and terminal position evaluation processing are repeatedly evaluated several times. . The number of times these processes have been performed is counted, and it is determined whether a preset number of rules has been reached (step 54). If it is less than the specified number of times, a series of processing is repeated. If the prescribed number of times is satisfied, it is determined whether all wireless tags 12 have been evaluated (step 55). If not, the process returns to step 52, and the wireless tag identification ID of the next wireless tag is set. After all the wireless tags 12 have been evaluated, the data is stored (step 56) and displayed on the display unit of the wireless LAN terminal 134 (step 57).
[0020]
As described above, it is possible to collect information related to transmission / reception states with the plurality of wireless tags 12 at the planned installation location of the wireless LAN terminal 13, and by extracting the wireless tag 12 optimal for communication from the information, the wireless tag 12 is extracted. Can be determined as an appropriate installation position of the base station 11.
Although an example in which a plurality of wireless LAN terminals 13 and wireless tags 12 are used has been described, for example, in a home wireless LAN, one wireless LAN terminal and one wireless tag are used, and similar question signals and response signals are used. By exchanging these, the appropriate position of the wireless tag 12 can be determined.
[0021]
Next, the signal transmission / reception process 133 of the wireless LAN terminal 13 will be described with reference to FIG.
The signal transmission / reception processing 133 of the wireless LAN terminal 13 records the radio wave transmission level and transmission time of the interrogation signal 210 to be transmitted (steps 61 and 62), adds the terminal identification ID to the interrogation signal 210 and transmits the interrogation signal 210 (step). 63). Since a timer is used to perform a reception operation for a certain period of time, it is initialized (step 64) and a reception operation is performed (step 65). Thereafter, it is determined whether or not the response signal 211 has been received (step 66). In the reception operation (step 65), the frequency of the response signal 211 is monitored, but if the synchronization signal cannot be extracted due to interference or the like, it is determined as “no reception”. If not received, the timer is updated (step 68), and it is determined from the timer value whether a fixed time has elapsed from the transmission time (step 69). If the predetermined time has elapsed, it is determined that the environment is incapable of transmitting / receiving radio waves (step 610), and the process is terminated.
If not, the process returns to the receiving operation 65.
[0022]
When it is determined that the response signal 211 has been received in the reception operation (step 65), the terminal identification ID is read from the response signal 211, and it is determined whether the terminal identification ID matches the identification ID of the own terminal (step 67). . If the terminal ID is another terminal ID, the process proceeds to the timer update operation (step 68). If the terminal IDs match, it is determined that the terminal ID is received (step 611), and the process is terminated.
By including the terminal identification ID in the question signal 210, the plurality of wireless LAN terminals 13 can simultaneously determine the communication state with the wireless tag 12.
[0023]
Next, processing of the terminal position evaluation program 134 will be described.
FIG. 7 is a flowchart showing the operation of the terminal position evaluation program 134.
First, signal transmission / reception processing is performed to determine whether or not a response signal 211 to the inquiry signal 210 transmitted from the terminal itself is received (step 71). If it is determined that the response signal 211 is received, the response signal 211 is recorded. The reception level and the reception time are recorded (steps 72 and 73). A radio wave attenuation rate is calculated from the transmission level recorded in step 61 of FIG. 6 and the reception level recorded in step 72 (step 74). Further, the transmission time between the wireless LAN terminal 13 and the wireless tag 12 is calculated from the transmission time recorded in step 62 and the reception time recorded in step 73 (step 75). Next, the BER is calculated by comparing the recorded BER determination code with the BER determination code included in the response signal 211 (step 76). Next, the wireless tag identification ID recorded in the response signal 211 and the attenuation rate, transmission time, and BER recorded in steps 74, 75, and 76 are recorded (step 77).
On the other hand, if it is determined in step 71 that reception is not possible, information indicating that reception is not possible is recorded (step 78).
[0024]
FIG. 8 shows an example of the structure of a record for recording evaluation data.
Here, for each wireless tag ID (1, 2,...), The attenuation rate, transmission time, and BER corresponding to the RFID tag ID (1, 2,. For data that cannot be received, information indicating that reception was not possible is written.
With the above processing, it becomes possible to evaluate the communication state of the place where the wireless LAN terminal 13 is installed in the environment equivalent to the wireless LAN system from the state before wiring.
[0025]
FIG. 9 shows a screen display example of the organized data. When a plurality of wireless tags 12 are arranged, the data is displayed so that the data can be divided and evaluated according to the wireless tag identification ID described in the response signal 211. In this display example, attenuation, transmission time, and average of BER are displayed. In the column of the wireless tag 12 that could not be received, a message to that effect (impossible to transmit / receive) is displayed.
Note that data stored in an external storage medium can be called up, and data measured at a plurality of points can be compared and examined. As a result, the user can also determine radio wave interference from a plurality of wireless LAN base stations.
[0026]
Therefore, for example, in the room shown in FIG. 10, if the wireless LAN terminal is scheduled to be used at the locations indicated by A and B, the wireless tag 12 is temporarily installed at the location indicated by P1, and the wireless LAN at the location A is indicated. The communication state with the terminal 13 is evaluated. Thereafter, the wireless LAN terminal 13 is placed at the point B, and the communication state is evaluated with the wireless tag 12 at the point P1. When the communication state is good at both the points A and B, a regular wireless LAN base station may be installed only at the point P1. However, if the communication state at point B is not good due to an obstacle such as the wall 101, a new position P2 at which communication with the point B can be satisfactorily selected is selected as a candidate site for the base station. Here, the communication state is evaluated again, and if it is good, a base station is also installed at point P2.
Therefore, it is only necessary to additionally purchase a base station when there is a terminal position where the communication state is not good, so that it is possible to suppress a wasteful economic burden.
[0027]
As described above, according to the present embodiment, a single wireless tag or a wireless tag built in the wireless LAN base station is provided with processing capability in order to evaluate the location of the wireless LAN base station and wireless LAN terminal. Thus, the wireless LAN base station can be moved freely, and in the environment equivalent to the actual state from before the wiring, a plurality of wireless LAN base stations, attenuation rates at transmission planned locations of wireless LAN terminals, transmission time, Communication state evaluation such as BER measurement is possible.
Also, it is possible to evaluate assuming that a plurality of wireless LAN base stations are installed, and evaluate how much radio wave interference is occurring at the position where the wireless LAN terminal is installed. It is possible. While looking at this evaluation, the wireless LAN base station or the wireless LAN terminal can be moved to find an optimum point for communication.
In addition, since data is held for each evaluation location, it is possible to simultaneously compare evaluations at a plurality of points, which is useful for improving the efficiency when considering the installation location.
[0028]
The wireless tag 12 can be provided as a wireless component that performs the operation shown in the flowchart of FIG. Further, the signal transmission / reception processing 133 and the terminal position evaluation program 134 can be provided as a computer program for performing the processing shown in the flowcharts of FIGS.
In the above description, the case where the position of the base station is selected while changing the position of the wireless tag has been described. However, when the base station is already fixed, the base station is normally connected to the fixed base station. Needless to say, the present invention can also be applied to the selection of the position of a mobile terminal capable of communication, and further to the evaluation of the communication state between an existing wireless base station and an existing wireless LAN terminal.
In addition, the case where the radio base station main body and the antenna are separated is applied when the position of the antenna is selected.
The contents evaluated by the terminal position evaluation program 134 may be only the presence / absence of a response signal to / from the wireless tag 12, and other than this, data such as an attenuation factor is obtained according to the required evaluation accuracy. Can be.
[0029]
【The invention's effect】
As described above, according to the present invention, it is possible to easily evaluate in an actual environment whether there is no need to supply power from the outside and where the wireless mobile terminal is located so that optimum communication can be performed. An appropriate location of the base station can be determined.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a wireless LAN system according to an embodiment of the present invention.
FIG. 2 is a configuration diagram showing operations of a wireless tag and a wireless LAN terminal.
FIG. 3 is a diagram illustrating an example of contents of a question signal and a response signal.
FIG. 4 is a flowchart showing an outline of a procedure of signal transmission / reception processing by a wireless tag.
FIG. 5 is a flowchart showing an outline of terminal position evaluation processing by a wireless LAN terminal.
FIG. 6 is a flowchart showing an outline of a procedure of signal transmission / reception processing by a wireless LAN terminal.
FIG. 7 is a flowchart showing a procedure of terminal position evaluation processing by a wireless LAN terminal.
FIG. 8 is a diagram illustrating a configuration example of a record for recording terminal position evaluation data.
FIG. 9 is a diagram showing an example of a screen showing a terminal position evaluation result.
FIG. 10 is a diagram illustrating an example of a room layout in which a wireless LAN base station is to be set.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Wireless LAN base station, 12 ... Wireless tag, 13 ... Wireless LAN terminal, 14 ... Wireless LAN antenna apparatus, 123 ... Signal transmission / reception process, 133 ... Signal transmission / reception process, 134 ... Terminal position evaluation program

Claims (5)

A method for determining an appropriate position of a wireless base station in a wireless LAN using a battery built-in wireless component capable of transmitting and receiving data in the same wireless frequency band as the wireless base station,
An interrogation signal is transmitted in the radio frequency band from the radio mobile terminal in a state where the radio mobile terminal is placed at a desired position within the movement range and the radio component is placed at a candidate position of the radio base station. Base station position determination of a wireless LAN characterized by monitoring the presence or absence of a response signal from the wireless component to a signal and determining whether the candidate position is an appropriate position of the wireless base station according to the content of the response Method. Transmitting an interrogation signal including identification information specific to a radio mobile terminal as the interrogation signal, identification information of the radio mobile terminal transmitting the interrogation signal as the response signal, identification information of the radio component itself, and reception level of the interrogation signal received A base station position determination method for wireless LAN according to claim 1, wherein a response signal including A wireless component with a built-in battery used to determine the appropriate position of a wireless base station in a wireless LAN,
A response including an inquiry signal transmitted in the same radio frequency band as that of the radio base station from a desired position within the movement range of the radio mobile terminal, and a response including the received level of the received interrogation signal and the received identification information of the radio mobile terminal A wireless component comprising means for returning a signal in the radio frequency band. A program that operates in a mobile radio terminal to determine an appropriate position of a radio base station in a wireless LAN using a battery built-in radio component that can transmit and receive data in the same radio frequency band as the radio base station,
Transmitting the interrogation signal to the radio component placed at the radio base station candidate position in the radio frequency band, monitoring the response signal from the radio component to the interrogation signal, and depending on the content of the response, the candidate position A computer-executable program comprising a process for evaluating whether or not is an appropriate position of a radio base station. An apparatus for determining an appropriate position of a wireless base station in a wireless LAN using a battery built-in wireless component capable of transmitting and receiving data in the same wireless frequency band as the wireless base station,
Identification information of the wireless mobile terminal that transmits the interrogation signal in the radio frequency band with the radio component placed at the candidate position of the radio base station and transmits the interrogation signal from the radio component for the interrogation signal, the radio component itself A wireless mobile terminal device comprising: display means for receiving a response signal including the identification information and the reception level of the received question signal and displaying the content of the response.

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