JP2007081457A - Radio station device and terminal for adjustment thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio station device capable of improving security by preventing leakage of radio waves to the outside of a radio communication area, regardless of the shape of the radio communication area, and to provide a terminal for adjustment thereof. <P>SOLUTION: The radio station device 1 is provided with a data-holding section 13 for holding data for determining the directivity and amplitude of a signal to be transmitted from an adaptive antenna 11; and an antenna control section 12 for controlling the directivity and amplitude of a signal to be transmitted from the adaptive antenna, in accordance with the data from the data holding section, thereby adjusting the radio communication area. The terminal 2 for adjustment is provided with a reception power detecting section 22 for detecting the strength of the signal received from the radio station device and outputting it as reception power; an input section 26 for inputting the transmission rate of data; and a data operating section 24 for calculating the data for determining the directivity and amplitude of the signal to be transmitted from the adaptive antenna, based on the reception power and the transmission rate. The terminal 2 transmits the data, calculated in the data operating section, to the radio station device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wireless station apparatus used as a wireless LAN access point in a wireless LAN (Local Area Network) system and an adjustment terminal thereof, and more particularly to a technique for limiting a wireless communication area.

  Conventionally, a wireless LAN system that transmits and receives data by wireless communication is known. In such a wireless LAN system, a terminal in a range where radio waves from a wireless station device used as a wireless LAN access point can reach other terminals or the wireless station device via the wireless LAN access point When connected to the Internet, the Internet can be accessed.

  In such a wireless LAN system, since communication between a wireless station apparatus used as a wireless LAN access point and a terminal is performed wirelessly, it is inevitable that communication contents leak to the outside. Thus, security is ensured by encrypting data communication between the radio station apparatus and the terminal.

  As a technique related to a wireless LAN using an adaptive antenna, Patent Document 1 discloses a wireless network control method capable of increasing the amount of communication information by suppressing co-channel interference, increasing the number of communications that can be simultaneously communicated, and increasing the amount of communication information. And a control device. In the technique disclosed in Patent Document 1, in a wireless network in which packet communication is performed between wireless stations, a neighbor including a measurement value of a signal-to-interference noise ratio when each adjacent wireless station receives a signal from the own station. Based on the signal from the radio station, the SINR (signal power to interference noise power ratio) seen from each adjacent radio station for each azimuth angle in the horizontal plane centered on the own station is obtained, and the maximum SINR is determined for each adjacent radio station. Is selected as an affinity with each adjacent wireless station, an adjacent link state table including the affinity and the corresponding azimuth angle is generated, and wireless communication is performed with the adjacent adjacent wireless station based on this. In addition, a communication table including the azimuth angle of each adjacent radio station that is in radio communication with another radio station is generated, and based on this, the azimuth angle of the adjacent radio station that is in radio communication with another radio station is generated. The radio signal is transmitted using an exclusive radiation pattern that directs the null point.

  As a technique related to a wireless communication system using an adaptive antenna, Patent Document 2 discloses an array antenna having a plurality of antenna elements, a smart antenna unit that controls the directivity of the array antenna, and a first antenna connected to the smart antenna unit. 1 radio base station and a control device detachably connected to the smart antenna unit. The control device has a weight information control unit that generates weight information for controlling the directivity of the plurality of antenna elements. The smart antenna unit includes a weight information storage unit that stores weight information, and a beam forming unit that forms directivity patterns of a plurality of antenna elements based on the weight information.

According to Patent Literature 2, weight information of a plurality of antenna elements is generated by a detachable control device based on received power at a smart antenna unit. For this reason, interference between radio base stations can be suppressed.
Japanese Patent Laid-Open No. 2003-115851 JP 2003-224502 A

  As described above, security in a conventional wireless LAN system is ensured by encrypting data communication, and the encryption method used for encryption is very difficult to decipher. However, there is no guarantee that encryption will not be decrypted in the future, and there is a problem that communication by encryption cannot be said to be absolutely safe.

  In addition, in a conventional wireless LAN system, a method of preventing leakage of radio waves outside the wireless communication area by changing the intensity of radio waves in stages is also considered. However, in this method, radio waves from the wireless LAN access point are transmitted with uniform intensity in all directions. Therefore, depending on the shape of the wireless communication area formed by the wireless LAN system, the intensity of the radio waves may be prevented in order to prevent radio wave leakage. If you decrease, the position where radio waves do not reach appears, and conversely, if the radio wave intensity is increased so that radio waves reach all positions, the radio waves used for wireless communication leak and are intercepted by a third party. There is a problem.

  An object of the present invention is to provide a radio station apparatus and an adjustment terminal for the radio station apparatus that can prevent radio waves from leaking outside the radio communication area and improve security regardless of the shape of the radio communication area.

  In order to solve the above-mentioned problem, a radio station apparatus according to a first invention includes an adaptive antenna, a data holding unit that holds data for determining a directivity direction and an amplitude of a signal transmitted from the adaptive antenna, and a data holding unit And an antenna control unit that adjusts the radio communication area by controlling the direction and amplitude of the signal transmitted from the adaptive antenna according to the data.

  A radio station apparatus according to a second aspect of the invention is the radio station apparatus according to the first aspect of the invention, wherein data for determining the directivity direction and amplitude held in the data holding unit from an adjustment terminal via a radio line is provided. It is further characterized by further comprising a receiving unit for receiving

  A radio station apparatus according to a third aspect of the invention is the radio station apparatus according to the first aspect of the invention, which is received by the adjustment terminal from the adjustment terminal via a transmission unit that transmits a radio signal and a radio line. A receiving unit that receives information related to the strength of the radio signal, and a data calculation unit that calculates data for determining a directivity direction and an amplitude of a signal transmitted from the adaptive antenna based on the information received by the receiving unit. It is further provided with the feature.

  The adjustment terminal according to the fourth aspect of the invention receives a received power detection unit that detects the intensity of a signal received from a radio station apparatus and outputs the received power, and a transmission rate of data to be transmitted / received by the radio station apparatus Data for determining the directing direction and amplitude of the signal transmitted from the adaptive antenna of the radio station apparatus based on the input unit to be received, the received power output from the received power detection unit, and the transmission rate input from the input unit It is characterized by comprising a data calculation unit and a transmission unit for transmitting data calculated by the data calculation unit to the radio station apparatus.

  According to the radio station apparatus of the first invention, the radio communication area is adjusted by controlling the directivity direction and the amplitude of the signal transmitted from the adaptive antenna according to the data from the data holding unit. By holding this data, it is possible to prevent radio waves from leaking outside the wireless communication area, and as a result, security can be improved.

  According to the radio station apparatus of the second invention, the receiving unit receives the data for determining the directivity direction and the amplitude held in the data holding unit from the adjustment terminal via the radio line. Thus, the wireless communication area can be adjusted by controlling the directivity direction and amplitude of the signal transmitted from the adaptive antenna.

  According to the radio station apparatus of the third invention, the transmission unit transmits a radio signal to the adjustment terminal, and the reception unit receives the radio signal received from the adjustment terminal via the radio line by the adjustment terminal. When the information related to the strength is received, the data calculation unit calculates the data for determining the directing direction and the amplitude of the signal transmitted from the adaptive antenna based on the information received by the receiving unit. Therefore, the adaptive antenna according to the calculated data The wireless communication area can be adjusted by controlling the directivity direction and amplitude of the signal transmitted from.

  Further, according to the adjustment terminal according to the fourth invention, the arrival state of the radio wave at a plurality of positions in the wireless communication area is measured, and the wireless communication area is adjusted based on the measurement result and the input transmission rate. To the wireless station device. Therefore, since the radio station apparatus can adjust the radio communication area by controlling the directivity direction and amplitude of the signal transmitted from the adaptive antenna, it is possible to limit the radio communication area where radio waves reach. As a result, radio waves can be prevented from leaking outside the wireless communication area, and security can be improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram illustrating a configuration of a wireless LAN system to which a wireless station apparatus (hereinafter referred to as “wireless LAN access point”) and an adjustment terminal according to Embodiment 1 of the present invention are applied. This wireless LAN system includes a wireless LAN access point 1, an adjustment terminal 2 and a plurality of terminals 3 ₁ to ₃ 3 existing in the wireless communication area A1.

  In FIG. 1, for convenience, the number of terminals is three, but the number of terminals constituting this wireless LAN system is arbitrary. The wireless communication area A1 indicates a range before the adjustment is made, and is a substantially circular shape centered on the wireless LAN access point 1.

The wireless LAN access point 1 performs wireless data transmission / reception between the adjustment terminal 2 and the terminals 3 _{1 to} 3 ₃ . The wireless LAN access point 1 is configured to be able to send and receive data to and from the network 5 via the modem 4. Details of the wireless LAN access point 1 will be described later.

  The adjustment terminal 2 determines the directivity direction and amplitude of the signal transmitted from the adaptive antenna 11 (to be described later) of the wireless LAN access point 1 based on the strength of the radio wave (signal) from the wireless LAN access point 1 and the input transmission speed. Data to be calculated is sent to the wireless LAN access point 1. Details of the adjustment terminal 2 will be described later.

Each terminal 3 ₁ to 3 _3, for example, a personal computer, which is composed of such as PDA (Personal Digital Assistance), via a wireless LAN access point 1 to access another terminal or network 5.

  Next, details of the wireless LAN access point 1 will be described. FIG. 2 is a block diagram showing the configuration of the wireless LAN access point 1 according to the first embodiment of the present invention. The wireless LAN access point 1 includes an adaptive antenna 11, an antenna control unit 12, a data holding unit 13, and a wireless LAN unit 14.

  The adaptive antenna 11 includes a plurality of antenna elements, and is configured so that the amplitude and phase of excitation of each antenna element can be controlled independently. The adaptive antenna 11 can freely change the phase. By changing the phase, the directivity, that is, the direction in which the radio wave can be best received or the null (even if the radio wave arrives) without moving the antenna element itself. The direction in which no reception is possible can be changed. The adaptive antenna 11 generates a radio wave according to a transmission signal sent from the antenna control unit 12 and transmits it in the air, receives a radio wave from the air, converts it into an electric signal, and receives the radio signal as an antenna signal. Send to. The adaptive antenna 11 has functions of a transmission unit and a reception unit that transmit and receive radio signals.

  The antenna control unit 12 generates a transmission signal in which the directing direction and amplitude of the signal transmitted from the wireless LAN unit 14 are controlled according to the phase / power data transmitted from the data holding unit 13, and sends the transmission signal to the adaptive antenna 11. . Further, the antenna control unit 12 sends the reception signal sent from the adaptive antenna 11 to the wireless LAN unit 14.

  The data holding unit 13 holds phase / power data for adjusting the directivity direction and amplitude of the radio wave transmitted from the adaptive antenna 11. The phase / power data held in the data holding unit 13 is transmitted from the adjustment terminal 2 by radio. Therefore, the adaptive antenna 11 receives the phase / power data held in the data holding unit 13 transmitted from the adjustment terminal 2 by radio.

  The wireless LAN unit 14 controls the entire wireless LAN access point 1. For example, the wireless LAN unit 14 sends a reception signal sent from the adaptive antenna 11 via the antenna control unit 12 to another device (not shown), and performs antenna control on a signal sent from the other device. Send to part 12. In addition, when the received signal transmitted from the adaptive antenna 11 via the antenna control unit 12 is the phase / power data transmitted from the adjustment terminal 2, the wireless LAN unit 14 determines the phase / power. Data is stored in the data holding unit 13.

  Next, details of the adjustment terminal 2 will be described. FIG. 3 is a block diagram illustrating the configuration of the adjustment terminal 2 according to the first embodiment of the present invention. The adjustment terminal 2 includes an antenna 21, a received power detection unit 22, a wireless LAN unit 23, a data calculation unit 24, a display unit 25, and an input unit 26.

  The antenna 21 receives the radio wave transmitted from the wireless LAN access point 1 and converts it into an electrical signal, sends it as a received signal to the received power detection unit 22, and according to the transmission signal sent from the received power detection unit 22 Generate radio waves and send them in the air. Note that an adaptive antenna need not be used as the antenna 21, and a normal antenna having one antenna element can be used.

  The received power detection unit 22 detects the intensity of the radio wave (signal) sent from the wireless LAN access point 1 based on the received signal sent from the antenna 21 and sends it to the data calculation unit 24 as received power. The reception power detection unit 22 passes the reception signal sent from the antenna 21 and sends it to the wireless LAN unit 23. Further, the reception power detection unit 22 transmits the signal transmitted from the wireless LAN unit 23 to the antenna 21 as a transmission signal.

  The wireless LAN unit 23 controls the entire adjustment terminal 2. For example, the wireless LAN unit 23 sends the reception signal sent from the reception power detection unit 22 to the data calculation unit 24 and sends the phase / power data sent from the data calculation unit 24 to the reception power detection unit 22. .

  The data calculation unit 24 is based on the received power transmitted from the received power detection unit 22 and the adaptive antenna 11 necessary for adjusting the direction and amplitude of the radio wave transmitted from the adaptive antenna 11 of the wireless LAN access point 1. The phase and power are calculated and sent to the wireless LAN unit 23 as phase / power data.

  The data calculation unit 24 also displays display data for displaying the directivity direction and amplitude of the radio wave to be transmitted from the adaptive antenna 11 of the wireless LAN access point 1 based on the phase / power data obtained by the calculation, Display data for displaying various messages is generated and sent to the display unit 25. Further, the data calculation unit 24 performs processing of data input from the input unit 26.

  The display unit 25 displays the directivity direction and amplitude of radio waves to be transmitted from the adaptive antenna 11 of the wireless LAN access point 1 and various messages based on the display data sent from the data calculation unit 24. The input unit 26 receives input from the user and sends it to the data calculation unit 24.

  Next, the operation of the wireless LAN system configured as described above will be described with reference to the flowchart shown in FIG.

  First, the operating conditions of the wireless LAN are input in the adjustment terminal 2 (step S11). That is, using the input unit 26, the size of the operation area for wireless communication and the installation position of the wireless LAN access point 1 are input. For example, as shown in FIG. 5, a rectangle 10 representing a wall of a room is input as an operation area, and one point in the rectangle 10 (in the example shown in FIG. Position) is entered. The area surrounded by the set points P <b> 1 to P <b> 7 in the rectangle 10 becomes the operation area 9. In step S <b> 11, the size of the wireless communication operation area and the installation position of the wireless LAN access point 1 input from the input unit 26 are sent to the data calculation unit 24.

  Next, a setting point for measuring the received power of the radio wave received from the wireless LAN access point 1 is input (step S12). FIG. 5 shows an example in which seven setting points P1 to P7 are input. Thereafter, the adjustment terminal 2 is moved to one of the previously set setting points, for example, a location corresponding to P1 (step S13). Next, the received power of the radio wave received from the wireless LAN access point 1 is measured (step S14). That is, the reception power detection unit 22 detects the intensity of the radio wave transmitted from the wireless LAN access point 1 and sends it to the data calculation unit 24 as reception power. The received power measured in step S14 is sent to the data calculation unit 24.

  When the measurement of the received power is completed, the transmission rate that can be used at the location (position P1) is displayed on the screen of the display unit 25 of the adjustment terminal 2 (step S15). The user selects a transmission rate to be used from the transmission rates displayed on the screen of the display unit 25, and inputs it using the input unit 26 (step S16). At this time, the displayed minimum transmission speed is the limit that radio waves reach, and it is preferable to select the minimum transmission speed in order not to leak the radio waves to the outside. In step S <b> 16, the transmission rate input from the input unit 26 is sent to the data calculation unit 24.

  Next, it is checked whether or not the measurement of the reception power for all the setting points has been completed (step S17). If it is determined in step S17 that the process has not been completed, the sequence returns to step S13, and processing for the next set point (measurement of received power and input of transmission rate) is performed.

  On the other hand, if it is determined in step S17 that the measurement of received power for all the set points has been completed, calculation of phase / power data is then performed (step S18). That is, the data calculation unit 24 calculates phase / power data for setting the directivity direction and amplitude of the adaptive antenna 11 of the adjustment terminal 2 based on the reception power and transmission rate at each setting point.

  Next, the phase / power data calculated in step S18 is transmitted to the wireless LAN access point 1 (step S19). That is, the phase / power data generated by the data calculation unit 24 is transmitted from the antenna 21 to the wireless LAN access point 1 by radio waves via the wireless LAN unit 23 and the reception power detection unit 22.

  In the wireless LAN access point 1, a reception signal output from the adaptive antenna 11 that has received the radio wave from the adjustment terminal 2 is sent to the wireless LAN unit 14. When the wireless LAN unit 14 determines that the received data is phase / power data, the wireless LAN unit 14 stores the phase / power data in the data holding unit 13.

  Thereafter, the antenna control unit 12 of the wireless LAN access point 1 generates a transmission signal in which the directivity direction and amplitude of the adaptive antenna 11 are controlled according to the phase / power data transmitted from the data holding unit 13, and the adaptive antenna 11 Send from. Thereby, the wireless communication area A2 as shown by the broken line in FIG. 1 is set, and leakage of the radio wave outside the wireless communication area A2 can be prevented.

As described above, according to the wireless LAN system according to the first embodiment of the present invention, the received power at the position where the terminals 3 _{1 to} 3 ₃ actually exist is measured, and the directivity of the radio wave transmitted from the adaptive antenna 11 is measured. Since the direction and amplitude are adjusted, a desired wireless communication area can be configured. Therefore, compared with the conventional wireless LAN system, the leakage of wireless radio waves outside the wireless communication area is reduced, so that interception by a third party can be prevented and security can be improved.

  In the wireless LAN system according to the first embodiment described above, the adjustment terminal 2 is configured to calculate the phase / power data, but the phase / power data is calculated at the wireless LAN access point 1. It can also be configured. In this case, the adjustment terminal 2 wirelessly inputs the operation conditions (the size of the wireless communication operation area and the installation position of the wireless LAN access point 1), the set point, the received power, and the transmission speed, which are input by the input unit 26. Transmit to the wireless LAN access point 1.

  That is, at the wireless LAN access point 1, the adaptive antenna 11 transmits a radio signal to the adjustment terminal 2, and the adaptive antenna 11 receives the intensity of the radio signal received from the adjustment terminal 2 by the adjustment terminal 2 via the radio line. Is received, the data calculation unit in the wireless LAN access point 1 calculates data for determining the direction and amplitude of the signal transmitted from the adaptive antenna 11 based on the received information. The wireless communication area can be adjusted by controlling the directivity direction and amplitude of the signal transmitted from the adaptive antenna 11 according to the data.

  In the wireless LAN system according to the first embodiment described above, the operation area is assumed to be in a room. However, the wireless LAN system can be applied even outdoors. In this case, it is conceivable that other radio waves are mixed with the received radio wave when the received power is measured at the adjustment terminal 2. However, the wireless LAN access point 1 transmits a radio wave including a predetermined ID, and the adjustment terminal 2 can avoid the inconvenience described above by configuring the reception power to be calculated only when a radio wave including the ID is received.

  The present invention can be used for a wireless LAN system and a wireless LAN access point.

1 is a diagram illustrating a configuration of a wireless LAN system to which a wireless station device (wireless LAN access point) and an adjustment terminal according to Embodiment 1 of the present invention are applied. It is a block diagram which shows the structure of the radio station apparatus (wireless LAN access point) which concerns on Example 1 of this invention. It is a block diagram which shows the structure of the terminal for adjustment which concerns on Example 1 of this invention. It is a flowchart which shows operation | movement of the wireless LAN system to which the wireless station apparatus (wireless LAN access point) and adjustment terminal which concern on Example 1 of this invention were applied. It is a figure for demonstrating operation | movement in the wireless LAN system to which the wireless station apparatus (wireless LAN access point) and adjustment terminal which concern on Example 1 of this invention were applied.

Explanation of symbols

1 Wireless station device (wireless LAN access point)
2 Adjustment terminal 3 _{1 to} 3 ₃ Terminal 11 Adaptive antenna 12 Antenna control unit 13 Data holding unit 14 Wireless LAN unit 21 Antenna 22 Received power detection unit 23 Wireless LAN unit 24 Data operation unit 25 Display unit 26 Input unit

Claims (4)

An adaptive antenna,
A data holding unit for holding data for determining a directivity direction and an amplitude of a signal transmitted from the adaptive antenna;
An antenna control unit that adjusts a wireless communication area by controlling a directivity direction and an amplitude of a signal transmitted from the adaptive antenna according to data from the data holding unit;
A radio station apparatus comprising:   The radio station apparatus according to claim 1, further comprising: a receiving unit that receives data for determining the directivity direction and amplitude held in the data holding unit from an adjustment terminal via a wireless line. A transmitter that transmits a radio signal;
A receiving unit that receives information on the strength of the radio signal received by the adjustment terminal from the adjustment terminal via a wireless line;
Based on the information received by the receiving unit, a data calculating unit that calculates data for determining the directing direction and amplitude of the signal transmitted from the adaptive antenna;
The radio station apparatus according to claim 1, further comprising: A received power detector that detects the intensity of the signal received from the radio station device and outputs the received power; and
An input unit for inputting a transmission rate of data to be transmitted and received by the radio station device;
Data calculation for calculating data for determining the directivity direction and amplitude of the signal transmitted from the adaptive antenna of the radio station apparatus based on the received power output from the received power detector and the transmission rate input from the input unit And
A transmission unit for transmitting data calculated by the data calculation unit to the radio station device;
An adjustment terminal comprising:

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