JP2014068134A - Radio communication terminal, radio communication device, radio communication system, and frequency band switching method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication device that can prevent long time interruption of communication when a frequency band used in communication is automatically switched.SOLUTION: When a control unit of a radio communication terminal 2000 has determined that communication quality has been deteriorated during communication at a first frequency band, it outputs a request signal for requesting switching to a second frequency band to a radio communication device 1000. Then, when the request signal has been received, a switching preparation unit of the radio communication device 1000 calculates certain clock time, and outputs a signal corresponding to the calculated clock time to a switching execution unit of the radio communication device 1000 and the control unit of the radio communication terminal 2000. When the clock time indicated by the signal corresponding to the clock time passed, the switching execution unit of the radio communication device 1000 switches the frequency band used in communication to the second frequency. When the clock time indicated by the signal corresponding to the clock time passed, the control unit of the radio communication terminal 2000 also switches the frequency band used in communication to the second frequency band.

Description

  The present invention relates to a radio communication terminal, a radio communication device, a radio communication system, and a frequency band switching method, and in particular, a radio communication terminal, a radio communication device, a radio communication system, and a frequency that switch frequency bands so that communication is not interrupted for a long time. It relates to a band switching method.

  In general, in a wireless LAN (Local Area Network), it is known that a terminal and an access point (hereinafter referred to as “AP”) communicate in a 2.4 GHz band or a 5 GHz band. However, when there is an electronic device near the terminal and the AP, the communication may be interrupted by radio waves emitted from the electronic device. For example, the microwave oven generally uses the 2.4 GHz band, but if the microwave oven is nearby, the terminal and the AP that are communicating in the same frequency band are disturbed by the leaked radio waves from the microwave oven. End up.

  FIG. 1 is a diagram illustrating an example in which communication between a terminal and an AP is interrupted by radio waves from an electronic device. The part delimited by the square is each room in the building. As shown in FIG. 1, AP1 and AP2 are installed on the second floor of the building. In addition, AP3 is installed on the first floor of the building, and electronic devices using radio waves in the 2.4 GHz band are also installed. In the room on the lower right of the first floor, a mobile terminal is used, and the mobile terminal communicates with AP3 in the 2.4 GHz band. Then, it is assumed that the electronic device operates when the mobile terminal moves to the room on the upper left of the second floor and communicates with AP1 in the 2.4 GHz band. At this time, the mobile terminal receives radio waves from the electronic device and is hindered from communicating with AP1. If the disturbing radio wave is strong, communication will be interrupted.

  As described above, Patent Document 1 discloses a technique for allowing a terminal and an AP to continue communication even when an electronic device is operated and a jamming wave is generated.

  The wireless communication device of Patent Document 1 operates as a base terminal corresponding to an AP or a portable terminal facing the AP, and constitutes a wireless LAN system. The wireless communication device of Patent Document 1 that is a base terminal and the wireless communication device of Patent Document 1 that is a portable terminal detect a radio wave that becomes a disturbance due to the use of a microwave oven or the like. Then, the wireless communication device of Patent Document 1 that is a base terminal and the wireless communication device of Patent Document 1 that is a portable terminal sequentially switch between the 2.4 GHz band and the 5 GHz band to transmit and receive certain data. Next, the wireless communication device of Patent Document 1 that is a base terminal and the wireless communication device of Patent Document 1 that is a portable terminal automatically select the frequency band with the least interference from the bit error rate of the received data after demodulation. To perform wireless communication in the selected frequency band.

  With the configuration and operation described above, the wireless communication device of Patent Document 1 automatically switches the frequency band for communication to the frequency band with the smallest interference even when an interference radio wave occurs. Communication with the wireless communication device can be continued.

JP 2002-33714 A

  However, the wireless communication device of Patent Document 1 automatically switches the frequency band for communication, but there is a problem that communication is interrupted for a long time when switching. This is because, even if the wireless communication device of Patent Document 1 switches the frequency band, the wireless communication device of Patent Document 1 that faces the wireless communication device does not always switch the frequency band. If the frequency bands of both the wireless communication device of Patent Document 1 and the wireless communication device of Patent Document 1 facing each other are not switched, communication is interrupted during that time.

  An object of the present invention is to provide a wireless communication terminal, a wireless communication apparatus, a wireless communication system, and a frequency band switching method that solve the above-described problems.

  In order to achieve the above object, a wireless communication terminal of the present invention is a wireless communication terminal capable of switching a frequency band for communicating with a facing wireless communication apparatus from a first frequency band to a second frequency band. A controller that outputs a request signal for requesting the wireless communication device to switch to the second frequency band when it is determined that communication quality has deteriorated during communication in the first frequency band; A frequency band switching unit that switches the first frequency band for performing communication to the second frequency band when the time has elapsed when a signal corresponding to the time is input.

  In order to achieve the above object, a wireless communication apparatus of the present invention is a wireless communication apparatus capable of switching a frequency band for communicating with a facing wireless communication terminal from a first frequency band to a second frequency band. When receiving a request signal for requesting switching to the second frequency band from the wireless communication terminal, a switching preparation unit that calculates a certain time and outputs a signal corresponding to the calculated time; A switching execution unit that switches the first frequency band for performing communication to the second frequency band when the time elapses.

  In order to achieve the above object, a wireless communication system of the present invention is a wireless communication system in which a wireless communication terminal and a wireless communication apparatus communicate with each other, and the wireless communication terminal communicates with a facing wireless communication apparatus. A wireless communication terminal capable of switching a band from a first frequency band to a second frequency band, and determining that communication quality has deteriorated during communication in the first frequency band, the wireless communication terminal When a control unit that outputs a request signal for requesting switching to the second frequency band and a signal corresponding to time are input to the device, communication is performed when the time has elapsed. A frequency band switching unit that switches a frequency band to the second frequency band, and the wireless communication device changes a frequency band for communicating with a facing wireless communication terminal from a first frequency band to a second frequency band. Switch to A wireless communication device capable of receiving a request signal for requesting switching to the second frequency band from the wireless communication terminal, calculating a certain time, and outputting a signal corresponding to the calculated time A switching preparation unit for outputting, and a switching execution unit for switching the first frequency band for performing communication to the second frequency band when the time has elapsed.

  In order to achieve the above object, a frequency band switching method of the present invention is a frequency band switching method for switching a frequency band for communication between a radio communication terminal and a radio communication device from a first frequency band to a second frequency band. When the wireless communication terminal determines that communication quality has deteriorated during communication in the first frequency band, the wireless communication terminal requests the wireless communication apparatus to switch to the second frequency band. When the wireless communication device receives the request signal, the wireless communication device calculates a certain time, outputs a signal corresponding to the calculated time, and performs communication when the time has elapsed. When the wireless communication terminal receives a signal corresponding to the time, the wireless communication terminal changes the first frequency band for communication when the time has elapsed to the second frequency band. Cut to frequency band Obtain.

  According to the present invention, the wireless communication device can prevent the communication from being interrupted for a long time when the frequency band for communication is automatically switched.

It is the figure which showed the example with which a terminal and AP are interrupted by the electromagnetic wave from an electronic device. It is a figure which shows the structural example of the radio | wireless communications system in the 1st Embodiment of this invention. It is a figure which shows the structural example of the radio | wireless communication apparatus in the 1st Embodiment of this invention. It is a figure which shows the structural example of the radio | wireless communication terminal in the 1st Embodiment of this invention. It is a figure for demonstrating operation | movement when the AP of the radio | wireless communication terminal in the 1st Embodiment of this invention is not detected. It is a figure for demonstrating the operation | movement (the process A part of FIG. 5) when not detecting AP of the radio | wireless communication terminal in the 1st Embodiment of this invention. It is a figure for demonstrating operation | movement when the corresponding | compatible frequency band confirmation signal of the radio | wireless communication apparatus in the 1st Embodiment of this invention is received. It is a figure for demonstrating operation | movement when the frequency band switch request signal of the radio | wireless communication apparatus in the 1st Embodiment of this invention is received. It is a figure for demonstrating operation | movement when detecting AP of the radio | wireless communication terminal in the 1st Embodiment of this invention. It is a figure for demonstrating operation | movement (operation | movement of the process C part of FIG. 8) when detecting AP of the radio | wireless communication terminal in the 1st Embodiment of this invention. It is a figure which shows the structural example of the radio | wireless communication terminal in the 2nd Embodiment of this invention. It is a specific example of MAP information used by the wireless communication terminal according to the second embodiment of the present invention. It is a figure for demonstrating operation | movement when the AP of the radio | wireless communication terminal in the 2nd Embodiment of this invention is not detected. It is a figure for demonstrating operation | movement when detecting AP of the radio | wireless communication terminal in the 2nd Embodiment of this invention. It is a figure for demonstrating operation | movement (operation | movement of the process E part of FIG. 13) when detecting AP of the radio | wireless communication terminal in the 2nd Embodiment of this invention. It is a specific example of AP information group with position information in the 2nd embodiment of the present invention. It is a figure which shows the structural example of the radio | wireless communications system in the 3rd Embodiment of this invention.

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

[First Embodiment]
[Description of configuration]
FIG. 2 is a diagram illustrating a configuration example of a wireless communication system according to the first embodiment of the present invention. FIG. 3 is a diagram illustrating a configuration example of the wireless communication apparatus according to the first embodiment of the present invention. Furthermore, FIG. 4 is a diagram illustrating a configuration example of a wireless communication terminal according to the first embodiment of the present invention.

(1) Configuration of Radio Communication System in First Embodiment of the Invention First, the radio communication system in the first embodiment includes a radio communication device 10 and a radio communication terminal 20 as shown in FIG. Composed. The wireless communication device 10 and the wireless communication terminal 20 are connected wirelessly.

(2) Configuration and Function of Wireless Communication Device 10 The wireless communication device 10 is a wireless LAN access point (hereinafter referred to as “AP”), and as shown in FIG. 3, a communication function unit 100 and a switching preparation unit. 101 and a switching execution unit 102. The communication function unit 100, the switching preparation unit 101, and the switching execution unit 102 are connected to each other.

  The communication function unit 100 can be realized using an electronic circuit or an FPGA (Field-Programmable Gate Array). The communication function unit 100 includes a memory such as a ROM (Read Only Memory). Further, the switching preparation unit 101 and the switching execution unit 102 can be realized using an electronic circuit, an FPGA, a DSP (Digital Signal Processor), a CPU (Central Processing Unit), or the like.

  The communication function unit 100 has a general wireless communication function. Moreover, the communication function part 100 respond | corresponds to one or both of 2.4 GHz band, 5 GHz band as a frequency band which performs communication. Whether the communication function unit 100 corresponds to one of the 2.4 GHz band, the 5 GHz band, or both is determined by the manufacturer of the wireless communication device 10 as in the case of a general AP. The communication function unit 100 stores information indicating a corresponding frequency band (hereinafter referred to as “corresponding frequency band information”) in a memory such as a ROM (Read Only Memory) provided by the manufacturer or user of the wireless communication device 10. Set and hold. Further, when a signal for confirming what the frequency band to which the communication function unit 100 corresponds (hereinafter referred to as “corresponding frequency band confirmation signal”) is input, the communication function unit 100 acquires the corresponding frequency band information held by itself, The corresponding frequency band information is output as a radio signal. In addition, when a signal requesting change of a frequency band for communication (hereinafter, referred to as “frequency band switching request signal”) is input, the communication function unit 100 outputs the input frequency band switching request signal, Acquires corresponding frequency band information held by itself. The communication function unit 100 confirms whether or not it corresponds to both the 2.4 GHz band and the 5 GHz band from the acquired corresponding frequency band information. When the communication function unit 100 is compatible with both the 2.4 GHz band and the 5 GHz band, the communication function unit 100 indicates that the communication function unit 100 supports both the 2.4 GHz band and the 5 GHz band (hereinafter referred to as “both frequency band compatible signals”). Is output. In addition, the communication function unit 100 recognizes, using a known function, whether the communication is performed in the 2.4 GHz band or the 5 GHz band after the communication is started, and a signal indicating the recognized frequency band (hereinafter “use”). Frequency band compatible signal ”). Further, the communication function unit 100 grasps, with a known function, whether a packet is being transmitted at predetermined intervals during communication, and a signal (hereinafter referred to as “a packet transmission”) indicating whether the packet is being transmitted or not. "Transmission status confirmation signal"). Further, when a signal indicating a frequency band is input, the communication function unit 100 switches the frequency band for communication to the frequency indicated by the signal. The predetermined period is set in the communication function unit 100 by the user of the wireless communication apparatus 10 of the present embodiment.

  When the frequency band switching request signal, the both frequency band compatible signal, and the used frequency band compatible signal are input, the switching preparation unit 101 determines the frequency band used for communication from the used frequency band compatible signal. Check. Furthermore, the switching preparation unit 101 determines whether or not communication is possible by changing the frequency band used for communication to another frequency band based on whether or not a predetermined condition is satisfied. Specifically, the switching preparation unit 101 measures a noise amount in a frequency band used for communication and a noise amount in another frequency band by a known technique, and the noise amount in another frequency band is determined. When it is smaller than the noise amount in the frequency band used for communication, it is determined that the frequency band can be changed to another frequency band. When switching preparation unit 101 determines that communication is possible after changing to another frequency band, switching preparation unit 101 outputs a response signal indicating that communication is possible even when switching to another frequency band. Furthermore, when the switching preparation unit 101 outputs a response signal indicating that communication is possible even when switching to another frequency band, the switching preparation unit 101 calculates a certain time and also outputs a signal indicating the calculated certain time. Specifically, the switching preparation unit 101 has a time function, and calculates the time when a predetermined time has elapsed from the time when the frequency band switching request signal is received as a constant time. The predetermined time is set in the switching preparation unit 101 by the user of the wireless communication apparatus 10 of the present embodiment. Note that the switching preparation unit 101 calculates a certain time after recognizing that the communication function unit 100 is not transmitting a packet from the input transmission state confirmation signal. When switching preparation unit 101 determines that communication is not possible after changing to another frequency band, switching preparation unit 101 outputs a response signal indicating that switching is not possible.

  When a signal indicating a certain time is input, the switching execution unit 102 outputs a signal indicating a frequency band different from the frequency band used for communication (hereinafter referred to as a “switching frequency band signal”) when a certain time has elapsed. Output.

(3) Configuration and Function of Wireless Communication Terminal 20 The wireless communication terminal 20 is a terminal compatible with a wireless LAN.

  As shown in FIG. 4, the wireless communication terminal 20 includes an antenna 201, a distribution unit 202, a 2.4 GHz wireless unit 203, a 5 GHz wireless unit 204, a modem unit 205, and a reception level measuring unit 206. . Furthermore, the wireless communication terminal 20 includes a reception quality measurement unit 207, a control unit 208, an AP detection unit 209, a frequency band switching unit 210, and an AP information storage unit 211.

  As shown in FIG. 4, the distribution unit 202 is connected to the antenna 201, the 2.4 GHz radio unit 203, and the 5 GHz radio unit 204. Further, the modem unit 205 is connected to the 2.4 GHz radio unit 203, the 5 GHz radio unit 204, the reception level measuring unit 206, and the frequency band switching unit 210. Furthermore, the reception level measurement unit 206 is connected to the reception quality measurement unit 207, and the frequency band switching unit 210 is connected to the 2.4 GHz radio unit 203 and the 5 GHz radio unit 204. The control unit 208 is connected to the modulation / demodulation unit 205, the reception quality measurement unit 207, the AP detection unit 209, the frequency band switching unit 210, and the AP information storage unit 211.

  The 2.4 GHz radio unit 203, the 5 GHz radio unit 204, and the modulation / demodulation unit 205 can be realized using an electronic circuit or an FPGA (Field-Programmable Gate Array). The reception level measurement unit 206, the reception quality measurement unit 207, the control unit 208, the AP detection unit 209, and the frequency band switching unit 210 may be realized using a DSP, a CPU, or the like in addition to the electronic circuit and the FPGA. The AP information storage unit 211 is realized by a memory such as a RAM (Random Access Memory). Distribution unit 202 is realized by a duplexer or a duplexer.

  The antenna 201 is an antenna corresponding to a general wireless LAN. That is, the antenna 201 emits an input high-frequency signal as a radio wave used in a general wireless LAN (hereinafter referred to as a “wireless LAN radio wave”). The antenna 201 outputs the input wireless LAN radio wave as a high-frequency signal.

  When a high frequency signal is input, the distribution unit 202 divides the high frequency signal into a 2.4 GHz band and a 5 GHz band and outputs each. In addition, when a high frequency signal in the 2.4 GHz band and the 5 GHz band is input, the distribution unit 202 outputs them.

  When a 2.4 GHz band high-frequency signal is input, the 2.4 GHz wireless unit 203 performs filtering, amplification, and the like, converts the signal into an intermediate frequency signal, and outputs the signal. When the intermediate frequency signal is input, the 2.4 GHz radio unit 203 performs filtering, amplification, and the like, converts the signal to a 2.4 GHz band high frequency signal, and outputs the signal. The 2.4 GHz radio unit 203 executes the above-described function when a signal for requesting operation start (described later in the function description of the control unit 208) is input. The 2.4 GHz radio unit 203 stops the above-described function when a signal for requesting operation stop (described later in the function description of the control unit 208) is input.

  When a 5 GHz band high frequency signal is input, the 5 GHz radio unit 204 performs filtering, amplification, etc., converts the signal into an intermediate frequency signal, and outputs the intermediate frequency signal. When the modulated intermediate frequency signal is input, the 5 GHz radio unit 204 performs filtering, amplification, and the like, converts the signal into a 5 GHz band high frequency signal, and outputs the signal. The 5 GHz radio unit 204 executes the above-described function when a signal for requesting operation start (described later in the function description of the control unit 208) is input. In addition, when a signal for requesting operation stop (described later in the function description of the control unit 208) is input, the 5 GHz radio unit 204 stops the above-described function.

  The modem unit 205 demodulates the input intermediate frequency signal, converts it into a baseband signal, and outputs the baseband signal. When the baseband signal is input, the modem unit 205 modulates and outputs it. Further, when a signal instructing the input / output destination is input, the modem unit 205 switches the input / output destination in accordance with the signal.

  The reception level measurement unit 206 measures the signal level of the input baseband signal (hereinafter referred to as “reception level”), and outputs the measured reception level together with the input baseband signal.

  Reception quality measuring section 207 measures a value corresponding to the communication quality of the input baseband signal. The value corresponding to the measured communication quality may be an error rate of the baseband signal, that is, BLER (Block Error Rate). The reception quality measurement unit 207 outputs values corresponding to the baseband signal, the reception level, and the communication quality.

  The control unit 208 holds a value indicating whether the AP detection unit 209 has detected an AP (hereinafter referred to as “AP detection presence / absence value”). When activated, the control unit 208 sets the AP detection presence / absence value to a value indicating that the AP detection unit 209 has not detected the AP. Furthermore, if the AP detection presence / absence value is a value indicating that the AP is not detected, the control unit 208 outputs a signal instructing to detect the AP. In addition, when a signal indicating AP detection is input after outputting a signal instructing AP detection, the control unit 208 sets the AP detection presence / absence value to a value indicating that the AP is detected. change. Further, the control unit 208 outputs a signal indicating the 2.4 GHz band, and as a result, when communication is performed in the 2.4 GHz band, a signal for confirming what the frequency band corresponding to the detected AP is, That is, the corresponding frequency band confirmation signal is converted into a baseband signal by a known technique and output. If the control unit 208 receives the corresponding frequency band information described above as a result of outputting the corresponding frequency band confirmation signal, the control unit 208 determines whether the detected AP corresponds to the 2.4 GHz band from the corresponding frequency band information. It is detected whether it corresponds to a belt or both. The control unit 208 outputs a signal indicating the 5 GHz band when the corresponding frequency band information cannot be received in the 2.4 GHz band after a predetermined time has elapsed. As a result of outputting a signal indicating the 5 GHz band, the control unit 208 outputs a corresponding frequency band confirmation signal again when communication is possible in the 5 GHz band. As a result, if the control unit 208 receives the corresponding frequency band information, the control unit 208 corresponds to whether the detected AP corresponds to the 2.4 GHz band, the 5 GHz band, or both from the corresponding frequency band information. Is detected. After detecting whether the detected AP corresponds to the 2.4 GHz band, the 5 GHz band, or both, the control unit 208 outputs a signal instructing to stop detecting the AP. Output. When the detected AP corresponds to both the 2.4 GHz band and the 5 GHz band, the control unit 208 has an input reception level greater than a predetermined level and a value corresponding to the input communication quality is a predetermined value. If smaller than, communication is performed in the frequency band in which the corresponding frequency band information is received. In addition, the control unit 208 stores a frequency band for performing communication. Note that the predetermined level and the predetermined value described above are set in the control unit 208 by the user of the wireless communication terminal 20 of the present embodiment. The control unit 208 should switch to a frequency band different from the frequency band from which the corresponding frequency band information is received when the input reception level is equal to or lower than the predetermined level or the value corresponding to the communication quality is equal to or higher than the predetermined value. Judge. The control unit 208 that has determined to switch to another frequency band is a signal that requests to change the frequency band for communication (frequency band that has received the corresponding frequency band information) to another frequency band, that is, the frequency band. The switching request signal is output as a baseband signal. As a result of outputting the frequency band switching request signal, the control unit 208 receives a response signal indicating whether or not communication is possible even when the frequency band for communication is switched to another frequency band and a signal indicating the time. . The control unit 208 checks whether the response signal is a signal indicating that communication is possible even after switching to another frequency band. When the response signal is a signal that can be communicated even when switched to another frequency band, the control unit 208 outputs a signal indicating the input time and a signal indicating another frequency band. In addition, after storing the frequency band for communication, the control unit 208 identifies the identifier corresponding to the detected AP (hereinafter referred to as “AP identification information”), the frequency band for communication, and AP information that associates the corresponding frequency band information. The group is stored in the AP information storage unit 211. Furthermore, after storing information such as AP identification information in the AP information storage unit 211, the control unit 208 checks whether the AP detection presence / absence value is a value indicating that an AP is detected. Further, if the AP detection presence / absence value is a value indicating that an AP is detected, the control unit 208 outputs a signal instructing AP detection. When a signal indicating AP detection is not input for a predetermined time, control unit 208 sets the AP detection presence / absence value to a value indicating that AP is not detected, and a signal for instructing to stop detecting AP Is output. The predetermined time is set in the control unit 208 by the user of the wireless communication terminal 20 of the present embodiment. The predetermined time is longer than the predetermined period. When a signal indicating AP detection is input, the control unit 208 acquires the AP information group stored in the AP information storage unit 211. Then, the control unit 208 obtains the corresponding frequency band information related to the AP identification information of the detected AP from the AP information group, and whether the AP detected from the corresponding frequency band information corresponds to both the 2.4 GHz band and the 5 GHz band. Confirm. When the detected AP corresponds to both the 2.4 GHz band and the 5 GHz band, the control unit 208 determines whether to switch to another frequency band again, and when switching, outputs the corresponding frequency band confirmation signal again. As a result, the corresponding frequency band confirmation information is obtained. The control unit 208 that has obtained the corresponding frequency band confirmation information associates the AP identification information, the frequency band communicated at that time, and the corresponding frequency band confirmation information, and stores them again in the AP information storage unit 211.

  When a signal instructing AP detection is input to the AP detection unit 209, the AP detection unit 209 detects the presence of the wireless communication apparatus 10 that can communicate with a known technique, that is, the AP (hereinafter referred to as "AP detection") To do. When detecting an AP, the AP detection unit 209 outputs a signal indicating AP detection and an identifier corresponding to the detected AP, that is, AP identification information. The AP detection unit 209 receives the signal instructing to stop detecting the AP, and the AP detection unit 209 stops the operation of detecting the AP.

  The frequency band switching unit 210 has a clock function. When the signal indicating the frequency and the signal indicating the time are input, the frequency band is recognized from the signal indicating the frequency band, and the time is recognized from the signal indicating the time. When the recognized time comes, the frequency band switching unit 210 performs control so that the frequency band with which the wireless communication apparatus 10 communicates is switched to the recognized frequency band. Specifically, when the recognized frequency band is the 2.4 GHz band, the frequency band switching unit 210 outputs a signal requesting operation start to the 2.4 GHz radio unit 203 at the recognized time, Then, a signal for requesting the operation stop is output to the radio unit 204 for 5 GHz. Further, the frequency band switching unit 210 outputs a signal having the 2.4 GHz radio unit 203 as an input / output destination to the modem unit 205. In addition, when the recognized frequency band is the 5 GHz band, the frequency band switching unit 210 outputs a signal requesting operation start to the radio unit 204 for 5 GHz at the recognized time, and outputs a signal requesting operation stop to 2 To 4 GHz radio unit 203. Further, the frequency band switching unit 210 outputs a signal that uses the 5 GHz radio unit 204 as an input / output to the modem unit 205. Note that when only a signal indicating a frequency is input, the frequency band switching unit 210 recognizes the frequency band from the signal indicating the frequency band. Further, the frequency band switching unit 210 performs control to switch to the recognized frequency band as described above when a predetermined time has elapsed from the time when the signal indicating the frequency is input. The predetermined time is set in the frequency band switching unit 210 by the user of the wireless communication terminal 20 of the present embodiment.

  The AP information storage unit 211 is a memory such as a RAM (Random Access Memory).

[Description of operation]
FIG. 5 is a diagram for explaining an operation when the AP of the wireless communication terminal is not detected in the first embodiment of the present invention. FIG. 6 is a diagram for explaining an operation (processing A part in FIG. 5) when the AP of the wireless communication terminal is not detected in the first embodiment of the present invention. Furthermore, FIG. 7A is a diagram for explaining an operation when a corresponding frequency band confirmation signal is received by the wireless communication device according to the first embodiment of the present invention. FIG. 7B is a diagram for explaining an operation when the radio communication device according to the first embodiment of the present invention receives a frequency band switching request signal. The operations of the wireless communication device 10 and the wireless communication terminal 20 will be described with reference to FIGS. The wireless communication terminal 20 operates differently when no AP is detected and when an AP is detected. Further, the wireless communication terminal 20 performs a frequency band setting operation and a transmission / reception operation among the operation when the AP is not detected and the operation when the AP is detected. Regarding the operation of the wireless communication terminal 20, after explaining the frequency band setting operation and transmission / reception operation, the operation when the AP of the wireless communication terminal 20 is not detected and the operation when the AP is detected explain.

(1) Frequency Band Setting Operation of Radio Communication Terminal 20 First, the frequency band setting operation of the radio communication terminal 20 will be described. In the frequency band setting operation, the frequency band for communication is set in each functional unit (that is, the frequency band switching unit 210, the 2.4 GHz radio unit 203, the 5 GHz radio unit 204, and the modem unit 205). It is an operation and is performed as follows.

  First, when the signal indicating the frequency band and the signal indicating the time are input from the control unit 208, the frequency band switching unit 210 of the wireless communication terminal 20 changes the frequency band from the signal indicating the frequency band and the signal indicating the time. Recognize time. In addition, when only the signal indicating the frequency band is input, the frequency band switching unit 210 of the wireless communication terminal 20 recognizes the frequency band from the signal indicating the frequency band, and further receives the signal indicating the frequency. The time when a predetermined time has elapsed from the time is recognized. When the recognized frequency band is the 2.4 GHz band, the frequency band switching unit 210 outputs a signal requesting operation start to the 2.4 GHz radio unit 203 at the recognized time, and stops the operation. The requested signal is output to the 5 GHz radio unit 204. The 2.4 GHz radio unit 203 operates its function when a signal requesting operation start is input. That is, the 2.4 GHz radio unit 203 converts the high frequency signal input from the distribution unit 202 into an intermediate frequency signal and outputs the intermediate frequency signal to the modem unit 205. The 2.4 GHz radio unit 203 converts the intermediate frequency signal input from the modulation / demodulation unit 205 into a high frequency signal and outputs the high frequency signal to the distribution unit 202. The 5 GHz radio unit 204 stops its function when a signal for requesting operation stop is input. Further, when the recognized time comes, the frequency band switching unit 210 outputs a signal instructing the modem unit 205 to use the 2.4 GHz radio unit 203 as an input / output destination. When a signal instructing that the 2.4 GHz radio unit 203 is the input / output destination is input, the modem unit 205 demodulates the intermediate frequency signal input from the 2.4 GHz radio unit 203 to generate a baseband signal. And output to the reception level measuring unit 206. Further, the modem unit 205 modulates the baseband signal input from the control unit 208 and outputs the modulated baseband signal to the 2.4 GHz radio unit 203.

  The operation of each functional unit when the above-described signal indicating the 2.4 GHz band is input is hereinafter referred to as “operation for setting the 2.4 GHz band”.

  In addition, when the recognized frequency band is the 5 GHz band, the frequency band switching unit 210 outputs a signal for requesting the operation start to the 5 GHz radio unit 204 and requests the operation stop when the recognized time comes. The signal is output to the 2.4 GHz radio unit 203. When a signal requesting to start operation is input, the 5 GHz radio unit 204 operates its function. That is, the 5 GHz radio unit 204 converts the high frequency signal input from the distribution unit 202 into an intermediate frequency signal and outputs the intermediate frequency signal to the modem unit 205. The 5 GHz radio unit 204 converts the intermediate frequency signal input from the modem unit 205 into a high frequency signal and outputs the high frequency signal to the distribution unit 202. The 2.4 GHz radio unit 203 stops its function when a signal for requesting operation stop is input. Furthermore, when the recognized time comes, the frequency band switching unit 210 outputs a signal instructing the modem unit 205 to use the 5 GHz radio unit 204 as an input / output destination. The modem unit 205 demodulates the intermediate frequency signal input from the 5 GHz radio unit 204 and converts it into a baseband signal when a signal instructing the 5 GHz radio unit 204 to be input / output is input. Output to the reception level measuring unit 206. Further, the modem unit 205 modulates the baseband signal input from the control unit 208 and outputs the modulated baseband signal to the 5 GHz radio unit 204.

  The operation of each functional unit when the above-described signal indicating the 5 GHz band is input is hereinafter referred to as “operation for setting the 5 GHz band”.

(2) Transmission Operation of Radio Communication Terminal 20 After the above-described frequency band setting operation is performed, the radio communication terminal 20 performs a transmission operation. The transmission operation is an operation in which the control unit 208 of the wireless communication terminal 20 outputs packet data or a control signal to be transmitted as a radio wave and is performed as follows.

  First, the control unit 208 converts packet data or a control signal to be transmitted into a baseband signal using a known technique, and outputs the baseband signal to the modem unit 205. The modem unit 205 modulates the input baseband signal to generate an intermediate frequency signal. At this time, if the above-described “operation for setting the 2.4 GHz band” is performed, the modem unit 205 outputs the intermediate frequency signal to the 2.4 GHz radio unit 203. When the intermediate frequency signal is input, the 2.4 GHz radio unit 203 performs filtering, amplification, and the like, converts the signal to a 2.4 GHz band high frequency signal, and outputs the high frequency signal to the distribution unit 202. When a high frequency signal is input, the distribution unit 202 generates radio waves via the antenna 201 and emits the radio waves toward the wireless communication device 10.

  The operation of each functional unit when transmitting in the 2.4 GHz band described above is hereinafter referred to as “2.4 GHz band transmission operation”.

  When the intermediate frequency signal is generated, the modem unit 205 outputs the intermediate frequency signal to the 5 GHz radio unit 204 if the above-described “operation for setting the 5 GHz band” is performed. When the intermediate frequency signal is input, the 5 GHz radio unit 204 performs filtering, amplification, and the like, converts the signal to a 5 GHz band high frequency signal, and outputs the signal to the distribution unit 202. When a high frequency signal is input, the distribution unit 202 generates radio waves via the antenna 201 and emits the radio waves toward the wireless communication device 10.

  The operation of each functional unit when transmitting in the above-mentioned 5 GHz band is hereinafter referred to as “5 GHz band transmission operation”.

(3) Reception Operation of Radio Communication Terminal 20 After the communication frequency band is set, the radio communication terminal 20 performs the following reception operation.

  First, the antenna 201 converts the received radio wave into a high frequency signal and outputs it to the distribution unit 202. Next, when the high frequency signal is input, the distribution unit 202 divides the high frequency signal into the 2.4 GHz band and the 5 GHz band, and outputs them to the 2.4 GHz radio unit 203 and the 5 GHz radio unit 204, respectively.

  At this time, if the “operation for setting the 2.4 GHz band” is performed, the 2.4 GHz radio unit 203 performs filtering, amplification, and the like on the input 2.4 GHz band high-frequency signal. , Converted to an intermediate frequency signal and output to the modem unit 205. Next, when the intermediate frequency signal is input from the 2.4 GHz radio unit 203, the modem unit 205 demodulates and converts the intermediate frequency signal into a baseband signal, and outputs the baseband signal to the reception level measurement unit 206.

  If the above-described “operation for setting the 5 GHz band” is performed, the 5 GHz radio unit 204 performs filtering, amplification, and the like on the input high frequency signal in the 5 GHz band to convert it to an intermediate frequency signal. And output to the modem unit 205. Next, when the intermediate frequency signal is input from the 5 GHz radio unit 204, the modem unit 205 demodulates and converts it into a baseband signal and outputs it to the reception level measuring unit 206.

Next, when the baseband signal is input from the modem unit 205, the reception level measurement unit 206 measures the signal level, that is, the reception level, and receives the measured reception level and the input baseband signal as reception quality. Output to the measurement unit 207.
Next, when the reception level and the baseband signal are input, the reception quality measuring unit 207 measures a value corresponding to the communication quality of the baseband signal. The value corresponding to the communication quality described above may be BLER. Reception quality measurement section 207 outputs values corresponding to the baseband signal, reception level, and communication quality to control section 208.

(4) Operation when the AP of the wireless communication terminal 20 is not detected The wireless communication terminal 20 performs the following operation when the AP is not detected. Specifically, the control unit 208 of the wireless communication terminal 20 confirms the AP detection presence / absence value held by itself, and if the value indicates that the AP detection unit 209 has not detected the AP, Perform the action. When the wireless communication terminal 20 is activated, the AP detection presence / absence value is set to a value indicating that no AP is detected, and thus the following operation is performed.

  First, when the control unit 208 of the wireless communication terminal 20 outputs a signal instructing AP detection to the AP detection unit 209, the AP detection unit 209 causes the AP detection unit 209 to perform every predetermined period as illustrated in FIG. 5. The AP is detected by a known method (S300). The predetermined period is set in the AP detection unit 209 by the user of the wireless communication terminal 20 of the present embodiment.

  Next, when the AP can be detected (in the case of YES in S300), the wireless communication terminal 20 determines whether the detected AP corresponds to the 2.4 GHz band, the 5 GHz band, or both. Is inquired of the AP (S301).

  Specifically, when AP is detected, AP detection section 209 outputs a signal indicating AP detection and an identifier corresponding to the detected AP, that is, AP identification information, to control section 208. The control unit 208 to which a signal indicating AP detection is input changes the AP detection presence / absence value held by itself to a value indicating that an AP is detected. Further, the control unit 208 outputs a signal indicating the 2.4 GHz band to the frequency band switching unit 210. The frequency band switching unit 210 to which a signal indicating the 2.4 GHz band is input performs the above-described “frequency band setting operation” using the 2.4 GHz radio unit 203 or the like, and the radio communication terminal 20 performs the 2.4 GHz band. It will be in the state which can communicate now. Next, the control unit 208 converts a signal that the AP requests to notify what the corresponding frequency band is, that is, the corresponding frequency band confirmation signal into a baseband signal using a known technique, and outputs the baseband signal to the modulation / demodulation unit 205. . The modem unit 205 performs the above-described “2.4 GHz band transmission operation” and outputs a corresponding frequency band confirmation signal to the AP in the 2.4 GHz band. Next, as described in “(5) Operation of the wireless communication device 10” described later, when the AP, that is, the wireless communication device 10 receives the corresponding frequency band confirmation signal, the AP corresponds to what frequency band. Information indicating whether the information is present, that is, the corresponding frequency band information is returned. Next, when the control unit 208 receives the corresponding frequency band information by the above-described “reception operation”, whether the detected AP corresponds to the 2.4 GHz band or the 5 GHz band from the corresponding frequency band information, or Detect if both are supported. In addition, since the opposing wireless communication device 10 may not be compatible with the 2.4 GHz band, the control unit 208 outputs a signal indicating the 5 GHz band when the corresponding frequency band information cannot be received after a predetermined time has elapsed. Output to the frequency band switching unit 210. The frequency band switching unit 210 to which a signal indicating the 5 GHz band is input performs the above-described “frequency band setting operation” using the 5 GHz radio unit 204 and the like, and the wireless communication terminal 20 can perform communication in the 5 GHz band. Become. Next, the control unit 208 converts the corresponding frequency band confirmation signal into a baseband signal using a known technique, and outputs the baseband signal to the modem unit 205. The modem unit 205 performs the above-described “5 GHz band transmission operation” and outputs a corresponding frequency band confirmation signal to the AP in the 5 GHz band. Next, when the control unit 208 receives the corresponding frequency band information by the above-described “reception operation”, whether the detected AP corresponds to the 2.4 GHz band or the 5 GHz band from the corresponding frequency band information, or Detect if both are supported. Here, the control unit 208 stores the frequency band in which the corresponding frequency band information is received. Next, the control unit 208 outputs a signal instructing to stop AP detection to the AP detection unit 209, and the AP detection unit 209 that has received the signal stops the operation of AP detection.

  Next, when the AP cannot be detected (No in S300), the wireless communication terminal 20 waits for the next cycle for detecting the AP. Specifically, the AP detection unit 209 waits for the next predetermined cycle for detecting the AP.

  Next, when the control unit 208 of the wireless communication terminal 20 detects that the AP corresponds to both the 2.4 GHz band and the 5 GHz band (YES in S301), the frequency band in which communication is performed in S301 is 2. .4 GHz band is confirmed (S302).

  Specifically, the control unit 208 stores the frequency band in which the corresponding frequency band information could be received in S301, but checks whether the frequency band is a 2.4 GHz band.

  Next, when the communication frequency band is the 2.4 GHz band (YES in S302), the control unit 208 of the wireless communication terminal 20 determines the reception level most recently acquired by the “reception operation” described above. The value corresponding to the communication quality is confirmed (S303).

  Specifically, the control unit 208 of the wireless communication terminal 20 has a reception level acquired from the reception level measurement unit 206 greater than a predetermined level, and a value corresponding to the communication quality acquired from the reception quality measurement unit 207 is predetermined. Check if the value is smaller than.

  Next, when the reception level is greater than a predetermined level (YES in S304) and the value corresponding to the communication quality, that is, the error rate of the received signal is smaller than the predetermined value (YES in S305). In the case of (2), communication is continuously performed in the 2.4 GHz band (S306). Specifically, the control unit 208 only stores that the frequency band for communication is the 2.4 GHz band.

  Next, the control unit 208 of the wireless communication terminal 20 stores at least AP identification information (obtained in S301), a frequency band for communication (stored in S301), and corresponding frequency band information (S301) in the AP information storage unit 211. Stored in association with each other (S307).

  Here, an example of the AP information group stored in the AP information storage unit 211 is described in the balloon portion of FIG. FIG. 4 shows a case where the AP identification information is an ESSID (Extended Service Set Identifier). The control unit 208 stores a frequency band for communication as communication frequency band information.

  In addition, when the reception level is equal to or lower than the predetermined level (No in S304) or the value corresponding to the communication quality is equal to or higher than the predetermined value (No in S305), the control unit 208 causes the interference wave to exceed the predetermined amount. Is generated and it is determined that the frequency band should be switched to another frequency band, and the following steps S309 to S312 are performed. As a result, the control unit 208 switches the frequency band for communication from the 2.4 GHz band to the 5 GHz band.

  First, the control unit 208 requests the AP to change the communication frequency band to the 5 GHz band (S309).

  Specifically, the control unit 208 converts a signal requesting to change the currently used frequency band to another frequency band, that is, a frequency band switching request signal to a baseband signal, and converts the signal to the modem unit 205. Output. Next, the modem unit 205 or the like outputs the input baseband signal (frequency band switching request signal) to the facing wireless communication apparatus 10 by the above-mentioned “2.4 GHz band transmission operation”.

  Next, as described in “(5) Operation of the wireless communication device 10” described later, when the wireless communication device 10 receives the frequency band switching request signal, the wireless communication device 10 switches the frequency band for communication to another frequency band. Also returns a response signal indicating whether communication is possible. Furthermore, if the wireless communication apparatus 10 can communicate by switching the current frequency band to another frequency band, the wireless communication apparatus 10 also returns a signal indicating the time. The control unit 208 of the wireless communication device 20 receives a response signal from the wireless communication device 10 and a signal indicating time by the above-described “reception operation”.

  Next, the control unit 208 confirms whether or not the received response signal is a signal indicating that communication is possible even after switching to another frequency band (S310).

  Next, when the response signal is a signal indicating that communication is possible even when the response signal is switched to another frequency band (YES in S310), the control unit 208 performs the above-described “operation for setting the 5 GHz band”. Communication is performed in another frequency band (5 GHz band) (S311).

Specifically, the control unit 208, as a signal indicating the frequency band, a signal indicating the 5 GHz band,
The received signal indicating the time is output to the frequency band switching unit 210. As a result, the above-described “operation for setting the 5 GHz band” is performed, and the wireless communication terminal 20 switches the frequency band for communication from the 2.4 GHz band to the 5 GHz band at the time recognized from the signal indicating the time. The control unit 208 stores that the frequency band for communication is the 5 GHz band.

  Although described in “(5) Operation of wireless communication device 10” described later, the wireless communication device 10 also switches the frequency band to the 5 GHz band at the time recognized from the signal indicating the time. As a result, the wireless communication device 10 and the wireless communication terminal 20 can be switched to the 5 GHz band at the same timing.

  Next, the control unit 208 of the wireless communication terminal 20 stores at least AP identification information (detected in S301), a frequency band for communication (stored in S311), and corresponding frequency band information (S301) in the AP information storage unit 211. And acquired as an AP information group (S312). Note that the control unit 208 stores a frequency band for communication as communication frequency band information.

  Next, when the response signal is a signal indicating that switching to another frequency band is not possible (No in S310), the control unit 208 performs the above-described S306 and S307 and continues the frequency band. Communication is performed at (2.4 GHz band). And the control part 208 memorize | stores that the frequency band which communicates is a 2.4 GHz band.

  In addition, when the AP does not support both the 2.4 GHz band and the 5 GHz band (in the case of No in S301), the control unit 208 of the wireless communication terminal 20 performs communication in the frequency band supported by the AP (S308). .

  Furthermore, when the frequency band with which communication is performed is not the 2.4 GHz band (No in S302), the control unit 208 performs the following S400 to S408 to determine the frequency band with which communication is performed.

  First, as shown in FIG. 6, the control unit 208 has a value corresponding to communication quality and a reception level acquired in S303 described above, and the reception level is greater than a predetermined level and the value corresponding to communication quality is It is confirmed whether it is smaller than a predetermined value (S400).

  Next, the control unit 208 of the wireless communication terminal 20 determines that the reception level is greater than the predetermined level (YES in S401) and the value corresponding to the communication quality is smaller than the predetermined value (YES in S402). ), Communication is continuously performed in the 5 GHz band (S403). Specifically, the control unit 208 only stores that the frequency band for communication is the 5 GHz band.

  Next, the control unit 208 of the wireless communication terminal 20 stores at least AP identification information (detected in S301), a frequency band for communication (stored in S403), and corresponding frequency band information (S301) in the AP information storage unit 211. Stored in association with each other (S404). Note that the control unit 208 stores a frequency band for communication as communication frequency band information.

  In addition, when the reception level is equal to or lower than a predetermined level (in the case of No in S401), or the value corresponding to the communication quality is equal to or higher than the predetermined value (in the case of No in S402), the control unit 208 Is determined, and it is determined that the frequency band should be switched to another frequency band, and the following steps S405 to S408 are performed. As a result, the control unit 208 switches the frequency band for communication from the 5 GHz band to the 2.4 GHz band.

  First, the control unit 208 requests the AP to change the communication frequency band to the 2.4 GHz band (S405).

  Specifically, the control unit 208 converts the frequency band switching request signal into a baseband signal and outputs the baseband signal to the modem unit 205. Next, the modem unit 205 or the like outputs the input baseband signal (frequency band switching request signal) to the facing wireless communication apparatus 10 by the above-described “5 GHz band transmission operation”.

  Next, as described in “(5) Operation of the wireless communication device 10” described later, when the wireless communication device 10 receives the frequency band switching request signal, the wireless communication device 10 switches the frequency band for communication to another frequency band. Also returns a response signal indicating whether communication is possible. Further, when the current frequency band can be switched to another frequency band, the wireless communication device 10 also returns a signal indicating the time. The control unit 208 of the wireless communication device 20 receives a response signal from the wireless communication device 10 and a signal indicating time by the above-described “reception operation”.

  Next, the control unit 208 checks whether or not the received response signal is a response signal indicating that communication is possible even after switching to another frequency band (S406).

  Next, when the response signal is a response signal indicating that communication is possible even if the response signal is switched to another frequency band (YES in S406), the control unit 208 sets the “2.4 GHz band described above. To perform communication "in another frequency band (2.4 GHz band) (S407).

  Specifically, the control unit 208 outputs a signal indicating the 2.4 GHz band and a received signal indicating the time to the frequency band switching unit 210 as signals indicating the frequency band. As a result, the above-described “operation for setting the 2.4 GHz band” is performed, and the wireless communication terminal 20 performs communication from the current frequency band of 5 GHz band to the 2.4 GHz band at the time of the signal indicating the time. Switch the frequency band to be performed. The control unit 208 stores that the frequency band for communication is the 2.4 GHz band.

  Next, the control unit 208 of the wireless communication terminal 20 stores at least AP identification information (detected in S301), a frequency band for communication (stored in S407), and corresponding frequency band information (S301) in the AP information storage unit 211. And acquired as an AP information group (S408). Note that the control unit 208 stores a frequency band for communication as communication frequency band information.

  Next, when the response signal is a signal indicating that switching to another frequency band is impossible (No in S406), the control unit 208 performs the above-described S403 and S404, and has been communicating so far. Communication in the selected frequency band (5 GHz band). And the control part 208 memorize | stores that the frequency band which communicates is a 5 GHz band.

  The operation when the AP of the wireless communication terminal 20 is detected for the first time has been described above.

(5) Operation of Wireless Communication Device 10 Next, the operation of the wireless communication device 10 will be described with reference to FIGS. 7A and 7B.

  First, as shown in FIG. 7A, the communication function unit 100 of the wireless communication device 10 confirms whether a corresponding frequency band confirmation signal (described above in S301) is received from the wireless communication terminal 20 at predetermined intervals (S500). ).

  The predetermined period is set in the communication function unit 100 by the user of the wireless communication apparatus 10 of the present embodiment.

  Next, when the communication function unit 100 receives the corresponding frequency band confirmation signal from the wireless communication terminal 20 (Yes in S500), the communication function unit 100 acquires the corresponding frequency band information held by itself and transmits the corresponding frequency band information to the radio signal. And output to the wireless communication terminal 20 (S501). At this time, the communication function unit 100 outputs the input corresponding frequency band confirmation signal to the switching preparation unit 101.

  Next, if the communication function unit 100 has not received the corresponding frequency band confirmation signal from the wireless communication terminal 20 (No in S500), the communication function unit 100 waits for a predetermined period to be confirmed next.

  Next, as shown in FIG. 7B, the communication function unit 100 checks whether a frequency band switching request signal (described above in S301) has been received from the wireless communication terminal 20 at predetermined intervals (S502). The predetermined period is set in the communication function unit 100 by the user of the wireless communication apparatus 10 of the present embodiment.

  Next, when the communication function unit 100 receives the frequency band switching request signal from the wireless communication terminal 20 (Yes in S502), the communication function unit 100 acquires the corresponding frequency band information held by itself, It is confirmed whether it corresponds to both 5 GHz bands (S503).

  Next, when the communication function unit 100 corresponds to both frequency bands of 2.4 GHz band and 5 GHz band (Yes in S503), the signal indicating that it corresponds to both frequency bands, that is, both frequency bands are supported. A signal is generated, and this signal is output to the switching preparation unit 101 (S504).

  Next, the communication function unit 100 recognizes the currently used frequency band in the 2.4 GHz band and the 5 GHz band with a known function, and switches the signal representing the recognized frequency band, that is, the signal corresponding to the used frequency band. Output to the preparation unit 101. Further, the communication function unit 100 also outputs the input frequency band switching request signal to the switching preparation unit 101.

  Next, when the frequency band switching request signal, the signals corresponding to both frequency bands, and the use frequency band compatible signal are input, the switching preparation unit 101 sets the frequency band currently used for communication from the use frequency band compatible signal to 2. It is confirmed whether it is a 4 GHz band (S505).

  Next, when the frequency band for communication is the 2.4 GHz band (Yes in S505), the switching preparation unit 101 changes the frequency band (2.4 GHz band) to another frequency band (5 GHz band). It is determined whether or not communication is possible even after the change (S506).

  Specifically, the switching preparation unit 101 measures a noise amount in a frequency band (2.4 GHz band) in which communication is currently performed and a noise amount in another frequency band (5 GHz band) by a known technique. Next, the switching preparation unit 101 determines that the noise amount in a predetermined condition, that is, in another frequency band (5 GHz band) is smaller than the noise amount in the frequency band (2.4 GHz band) in which communication is currently performed. When it is satisfied, it is determined that communication is possible even if the frequency band is changed to another frequency band (5 GHz band).

  Next, when the switching preparation unit 101 determines that communication is possible even when the frequency band is changed to another frequency band (5 GHz band) (Yes in S506), the switching preparation unit 101 recognizes whether the communication function unit 100 is transmitting a packet (S507). ).

  Specifically, the communication function unit 100 recognizes whether a packet is being transmitted at a predetermined cycle by a known function, and is a signal indicating that a packet is being transmitted or is not being transmitted. A state confirmation signal is output to the switching preparation unit 101. The switching preparation unit 101 recognizes whether a packet is being transmitted from the transmission state confirmation signal input from the communication function unit 100.

  Next, when the switching preparation unit 101 recognizes that the communication function unit 100 is transmitting a packet (Yes in S507), the signal indicating that the transmission status confirmation signal input from the communication function unit 100 is not transmitting a packet. As soon as it becomes, the following frequency band switching process is performed (S508).

  First, the switching preparation unit 101 outputs to the communication function unit 100 a response signal indicating that communication is possible even when switching to another frequency band (5 GHz band). Furthermore, the switching preparation unit 101 calculates a time when a predetermined time has elapsed from the time when the frequency band switching request signal is received, and sets the time as a fixed time. Alternatively, the switching preparation unit 101 may calculate a time when a predetermined time has elapsed from the time when the response signal is output, and set the time as a fixed time. The switching preparation unit 101 outputs a signal indicating the calculated fixed time to the communication function unit 100, and then the communication function unit 100 sends the input response signal and the signal indicating the time to the wireless communication terminal 20. Output. For the predetermined time described above, after the switching preparation unit 101 receives the frequency band switching request signal, a signal indicating the time arrives at the radio communication terminal 20 and is input to the frequency band switching unit 210 of the signal radio communication terminal 20. This is a longer time than The signal indicating the time is input to the frequency band switching unit 210 of the wireless communication terminal 20 as described above in S311 and S407. Here, the time from when the switching preparation unit 101 receives the frequency band switching request signal to when the signal indicating the time is input to the frequency band switching unit 210 of the wireless communication terminal 20 is hereinafter referred to as “preparation time”. The user of the wireless communication apparatus 10 according to the present embodiment can actually obtain the preparation time and set it in the switching preparation unit 101 as a predetermined time. Next, the switching preparation unit 101 outputs a response signal indicating that communication is possible even after switching to another frequency band (5 GHz band), and then a switching frequency that is a signal indicating another frequency band (5 GHz band). A band signal and a signal indicating a certain time are output to the switching execution unit 102. Further, when a switching frequency band signal and a signal indicating a certain time are input from the switching preparation unit 101, the switching execution unit 102 sends the switching frequency band signal to the communication function unit 100 when the time indicated by the signal has elapsed. Output. As soon as the switching frequency band signal is input from the switching execution unit 102, the communication function unit 100 switches to the frequency band (5 GHz band) indicated by the switching frequency band signal and performs wireless communication.

  Next, when the communication function unit 100 recognizes that the packet is not being transmitted (No in S507), the switching preparation unit 101 performs the same process as the frequency band switching process performed in S508 described above (S509).

  Next, when the frequency band for performing communication is not the 2.4 GHz band (No in S505), the switching preparation unit 101 sets the frequency band for performing communication (5 GHz band) to another frequency band (2. It is determined whether or not communication is possible by changing to 4 GHz band (S511).

  Specifically, the switching preparation unit 101 satisfies the predetermined condition, that is, the noise amount in another frequency band (2.4 GHz band) is the noise amount in the frequency band (5 GHz band) in which communication is currently performed. If it is smaller than that, it is determined that communication is possible.

  Next, when the switching preparation unit 101 determines that communication is possible even if the frequency band is changed to another frequency band (2.4 GHz band) (Yes in S511), the switching preparation unit 101 performs the above-described processing of S507 to S509 and performs communication. Switch the frequency band to be performed to the frequency band (5 GHz band).

  Next, when the switching preparation unit 101 determines that communication is not possible by changing to another frequency band (2.4 GHz band) (No in S511), a response signal indicating that switching cannot be performed is a communication function. Output to the unit 100. Then, the communication function unit 100, to which the response signal indicating that switching to the frequency band is impossible is input, notifies the wireless communication terminal 20 of the response signal (S510).

  Next, the communication function unit 100 also indicates that it is not possible to switch to the frequency band, similarly to S510, even when it does not support both the 2.4 GHz band and the 5 GHz band (in the case of No in S503). The response signal is notified to the wireless communication terminal 20.

  The operation when the wireless communication device 10 has not detected the AP has been described above.

(6) Operation when Detecting AP of Wireless Communication Terminal 20 FIG. 8 is a diagram for explaining the operation when detecting the AP of the wireless communication terminal in the first embodiment of the present invention. It is. FIG. 9 is a diagram for explaining the operation when the AP of the wireless communication terminal according to the first embodiment of the present invention is detected (the operation of the process C portion in FIG. 8). Hereinafter, an operation when an AP is detected will be described with reference to FIGS.

  First, the control unit 208 of the wireless communication terminal 20 checks the AP detection presence / absence value held by itself, and if it is a value indicating that an AP is detected, as shown in FIG. It is determined whether the frequency band for communication is the 2.4 GHz band (S600).

  Since the control unit 208 stores the frequency band for communication in the above-described S306 and the like, the control unit 208 can perform the determination in S600.

  Next, when the frequency band for communication is the 2.4 GHz band (Yes in S600), the control unit 208 detects a signal instructing AP detection as in the case of S300 described above. The AP detection unit 209 detects the AP (S601).

  Next, when the AP detection unit 209 detects an AP (Yes in S601), the control unit 208 acquires an AP information group stored in the AP information storage unit 211, and the detected AP is 2. It is confirmed whether it corresponds to both the 4 GHz band and the 5 GHz band (S602).

  Specifically, when AP is detected, AP detection section 209 outputs a signal indicating AP detection and AP identification information to control section 208. Also, the control unit 208 acquires an AP information group stored in the AP information storage unit 211. Next, the control unit 208 acquires corresponding frequency band information corresponding to the input AP identification information from the AP information group. Then, the control unit 208 confirms from the acquired corresponding frequency band information whether the detected AP corresponds to both the 2.4 GHz band and the 5 GHz band.

  Next, when the AP cannot be detected (No in S601), the AP detection unit 209 waits for the next cycle for detecting the AP. When the control unit 208 does not receive a signal indicating AP detection from the AP detection unit 209 for a predetermined time, the control unit 208 sets the AP detection presence / absence value as a value indicating that no AP is detected, and stops detecting the AP. A signal instructing this is output to the AP detection unit 209. Further, the control unit 208 returns to the operation of S300 described above.

  Next, when the AP corresponds to both the 2.4 GHz band and the 5 GHz band (in the case of YES in S602), the control unit 208 described above “(4) When the AP of the wireless communication terminal 20 is not detected” The above-described S303 to S306 and S309 to S311 are performed in the same procedure as the “operation”.

  Next, the control unit 208 that has performed S311 associates the AP identification information acquired in S602, the frequency band for communication confirmed in S600, and the corresponding frequency band information acquired in S602, and stores AP information as an AP information group. The data is stored in the unit 211 (S603).

  Note that the control unit 208 stores the frequency band for performing the communication confirmed in S600 as communication frequency band information. When the same AP identification information as the AP identification information to be stored has already been stored in the AP information storage unit 211, the control unit 208 can correspond to the corresponding frequency band information and communication frequency band information associated with the AP identification information. Is updated with the information to be stored.

  Next, when it is confirmed that the AP does not support both the 2.4 GHz band and the 5 GHz band (in the case of No in S602), the control unit 208 of the wireless communication terminal 20 currently uses the frequency band 2. Communication is continuously performed in the 4 GHz band (S604).

Next, when the frequency band for communication is not the 2.4 GHz band (in the case of No in S600), the control unit 208 currently sets the frequency band for communication to the 5 GHz band as shown in FIG. (S605)
Next, as in S300 described above, the control unit 208 outputs a signal instructing AP detection to the AP detection unit 209, and the AP detection unit 209 detects the AP (S606).

  Next, when the AP detection unit 209 detects an AP (Yes in S606), the control unit 208 acquires the AP information group stored in the AP information storage unit 211, and the detected AP is 2.4 GHz. It is confirmed whether it corresponds to both the band and the 5 GHz band (S607).

  Specifically, when AP is detected, AP detection section 209 outputs a signal indicating AP detection and AP identification information to control section 208. Next, the control unit 208 acquires corresponding frequency band information corresponding to the input AP identification information from the AP information group. Then, the control unit 208 confirms from the acquired corresponding frequency band information whether the detected AP corresponds to both the 2.4 GHz band and the 5 GHz band.

  Next, when the AP cannot be detected (No in S606), the AP detection unit 209 waits for the next cycle for detecting the AP. When the control unit 208 does not receive a signal indicating AP detection from the AP detection unit 209 for a predetermined time, the control unit 208 sets the AP detection presence / absence value as a value indicating that no AP is detected, and stops detecting the AP. A signal instructing this is output to the AP detection unit 209. Further, the control unit 208 returns to the operation of S300 described above.

  Next, when the AP corresponds to both the 2.4 GHz band and the 5 GHz band (in the case of YES in S606), the control unit 208 described above “(4) When the AP of the wireless communication terminal 20 is not detected” The above-described S401 to S403 and S405 to S407 are performed in the same procedure as the “operation”.

  Next, the control unit 208 that implemented S407 associates the AP identification information acquired in S606, the frequency band switched in S407, and the corresponding frequency band information acquired in S607, and stores them in the AP information storage unit 211 as an AP information group. Store (S609).

  Note that the control unit 208 stores the frequency band switched in S407 as communication frequency band information. When the same AP identification information as the AP identification information to be stored has already been stored in the AP information storage unit 211, the control unit 208 can correspond to the corresponding frequency band information and communication frequency band information associated with the AP identification information. Is updated with the information to be stored.

  Next, when it is confirmed that the AP does not support both the 2.4 GHz band and the 5 GHz band (in the case of No in S607), the control unit 208 of the wireless communication terminal 20 currently uses the frequency band 5 GHz band in which communication is performed. Then, communication is continued (S608).

  Next, when the processing of any of S604, S306, S603, S608, S403, and S609 described above is completed, the control unit 208 returns to S600 described above.

[Description of effects]
According to the present embodiment, the wireless communication device 10 and the wireless communication terminal 20 that are wireless communication devices can prevent communication from being interrupted for a long time when the frequency band for communication is automatically switched. it can. The reason is that the radio communication device 10 and the radio communication terminal 20 switch the frequency band at the same time with matching timing.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. In the first embodiment, when a wireless communication terminal has not detected an AP, the wireless communication terminal measures a reception level and obtains a frequency band for communication. In the second embodiment, the wireless communication terminal Finds a frequency band for communication using position information indicating its own position.

[Description of configuration]
FIG. 10 is a diagram illustrating a configuration example of a wireless communication terminal according to the second embodiment of the present invention. FIG. 11 is a specific example of MAP information used by the wireless communication terminal according to the second embodiment of the present invention.

  As illustrated in FIG. 10, the wireless communication terminal 70 according to the second embodiment includes a control unit 708 and an AP information storage unit 711 instead of the control unit 208 and the AP information storage unit 211. Furthermore, the wireless communication terminal 70 in the second embodiment also includes a GPS (Global Positioning System) antenna 712, a GPS wireless unit 713, a GPS demodulation unit 714, and a position information determination unit 715.

  The GPS wireless unit 713 is connected to the GPS antenna 712 and the GPS demodulation unit 714, and the GPS demodulation unit 714 is connected to the position information determination unit 715. The control unit 708 is connected to the AP information storage unit 711 and the position information determination unit 715.

  The GPS wireless unit 713, the GPS demodulation unit 714, and the position information determination unit 715 can be realized using an electronic circuit or an FPGA. The control unit 708 can be realized using a DSP, a CPU, or the like in addition to the electronic circuit and the FPGA. The AP information storage unit 711 is realized by a memory such as a RAM.

(1) Functions of Functional Units Constructing Wireless Communication Terminal 70 The functions of the functional units constituting the wireless communication terminal 70 will be described below.

  The GPS antenna 712 receives a radio wave transmitted from a GPS satellite at a predetermined cycle, converts it to a high frequency signal, and outputs it. The predetermined period is set in the GPS antenna 712 by the user of the wireless communication terminal 70 of the present embodiment.

  The GPS wireless unit 713 amplifies the input high-frequency signal, down-converts it to an intermediate frequency signal, performs A / D conversion, and outputs it as a digital signal.

  When the digital signal is input, the GPS demodulator 714 performs code demodulation and outputs a navigation message obtained as a result.

  When the navigation message is input, the position information determination unit 715 calculates the position of the wireless communication terminal 70 by a known method. When a signal requesting the position information of the wireless communication terminal 70 is input, the position information determination unit 715 outputs information (hereinafter referred to as “position information”) that represents the position of the wireless communication terminal 70 calculated most recently.

  When a signal indicating AP detection and AP identification information are input, the control unit 708 outputs a signal requesting position information of the wireless communication terminal 70. When the position information of the wireless communication terminal 70 is input, the control unit 708 confirms the MAP information and obtains a frequency band to be preferentially communicated. As shown in FIG. 11, the MAP information is a table in which a communication area is associated with a frequency band in which communication is possible. The MAP information is set in the control unit 708 by the user of the wireless communication terminal 70 of this embodiment before the control unit 708 is activated. The control unit 708 finds a communication area including the position indicated by the position information from the communication areas described in the MAP information, and sets a frequency band associated with the area as a frequency band to be preferentially communicated. If the frequency band to be preferentially communicated is the 2.4 GHz band, the control unit 708 performs communication in the 2.4 GHz band and outputs a signal requesting location information of the wireless communication terminal 70. If the frequency band to be preferentially communicated is not the 2.4 GHz band, the control unit 708 performs communication in the 5 GHz band and outputs a signal requesting location information of the wireless communication terminal 70. In addition, the control unit 708 stores a frequency band for communication. Further, when the position information of the wireless communication terminal 70 is input, the control unit 708 receives at least the input position information, AP identification information, a frequency band for communication, and a corresponding frequency in the AP information storage unit 711. Stores the band information in association with each other. Further, when the communication frequency band is switched, the control unit 708 stores the position information, the AP identification information, the frequency band for performing communication after switching, and the corresponding frequency band information in the AP information storage unit 711 in association with each other. To do. At this time, the control unit 708 stores a frequency band for communication as communication frequency band information. Further, the control unit 708 updates the MAP information when the frequency band for communication is switched. The updating method will be described in detail in the description of the operation described later.

  The AP information storage unit 711 is a memory such as a RAM (Random Access Memory).

  Since configurations and functions other than those described above are the same as those of the wireless communication terminal according to the first embodiment, the same reference numerals are given and description thereof is omitted.

[Description of operation]
The radio communication terminal according to the second embodiment determines a frequency band for communication by using position information and MAP information. The operation of the radio communication terminal in the second embodiment will be described below. The operation of the wireless communication terminal in the second embodiment is divided into three operations: a position grasping operation, an operation when no AP is detected, and an operation when an AP is detected.

(1) Position grasping operation of wireless communication terminal 70 First, the wireless communication terminal 70 calculates information indicating its own position (hereinafter referred to as “position information”). Specifically, the GPS antenna 712 receives radio waves transmitted from GPS satellites at a predetermined cycle, and outputs the radio waves to the GPS radio unit 713 as a high frequency signal. When a high-frequency signal is input, the GPS wireless unit 713 amplifies it, down-converts it to an intermediate frequency signal, performs A / D conversion, and outputs it to the GPS demodulation unit 714 as a digital signal. When a digital signal is input, the GPS demodulation unit 714 performs code demodulation and outputs a navigation message obtained as a result to the position information determination unit 715. When the navigation message is input, the position information determination unit 715 calculates the position of the wireless communication terminal 70 by a known method. When the position information determination unit 715 receives a signal requesting position information from the control unit 708, the position information determination unit 715 outputs the most recently calculated position information of the wireless communication terminal 70 to the control unit 708.

(2) Operation when wireless communication terminal 70 does not detect AP FIG. 12 is a diagram for explaining the operation when wireless communication terminal AP is not detected in the second embodiment of the present invention. It is. The operation when the AP of the wireless communication terminal 70 is not detected will be described using FIG.

  First, the control unit 708 of the wireless communication terminal 70 confirms the AP detection presence / absence value held by itself, and performs the following operation if the value indicates that the AP detection unit 209 has not detected an AP. .

  First, as shown in FIG. 12, the wireless communication terminal 70 outputs a signal instructing AP detection to the AP detection unit 209, and the AP detection unit 209 that has received the signal detects AP detection. This is performed by a known method (S800). S800 is the same operation as S300 described above.

  Next, when the AP can be detected (YES in S800), the wireless communication terminal 70 obtains a frequency band to be preferentially communicated from the position information and the MAP information of the wireless communication terminal 70 (S801).

  Specifically, first, when detecting an AP, the AP detection unit 209 of the wireless communication terminal 70 outputs a signal indicating AP detection and an identifier corresponding to the detected AP, that is, AP identification information, to the control unit 708. To do. Next, when a signal indicating AP detection and AP identification information are input, control unit 708 outputs a signal requesting position information of wireless communication terminal 70 to position information determination unit 715. The position information determination unit 715 outputs the most recently calculated position information of the wireless communication terminal 70 to the control unit 708. When the position information of the wireless communication terminal 70 is input, the control unit 708 finds a communication area including the position indicated by the position information from the communication areas described in the MAP information, and can perform communication associated with the area. This frequency band is a frequency band to be preferentially communicated. For example, it is assumed that the control unit 708 has the MAP information shown in FIG. 11 set, and the position information determination unit 715 receives 15 degrees 1 minute east longitude and 15 degrees 1 north latitude as the position information. In this case, the control unit 708 includes, in the communication area described in the MAP information, the communication area including the position of the input position information is 15 degrees 1 minute east longitude / 15 degrees 1 minute north latitude to 15 degrees 1 minute east longitude / The area is 15 degrees and 2 minutes north latitude. The control unit 708 sets the communicable frequency band 2.4 GHz band associated with this area as a frequency band to be preferentially communicated.

  Next, the wireless communication terminal 70 inquires of the AP whether the AP detected in S800 corresponds to the 2.4 GHz band, the 5 GHz band, or both (S802). The specific operation of S802 is the same as the operation of S301 described above.

  Next, the control unit 708 of the wireless communication terminal 70 determines whether the frequency band to be preferentially communicated (obtained in S801) is the 2.4 GHz band (S803).

  Next, when the frequency band to be preferentially communicated is the 2.4 GHz band (in the case of YES in S803), the wireless communication terminal 70 performs communication in the 2.4 GHz band and obtains position information of the wireless communication terminal 70. Obtain (S804).

  Specifically, the control unit 708 outputs a signal requesting the position information of the wireless communication terminal 70 to the position information determination unit 715. The position information determination unit 715 to which a signal requesting the position information of the wireless communication terminal 70 is input outputs the position information of the wireless communication terminal 70 calculated most recently to the control unit 708. As a result, the control unit 708 acquires the position information of the wireless communication terminal 70. In addition, the control unit 708 stores that the frequency band for communication is the 2.4 GHz band.

  Next, the control unit 708 acquires at least the position information acquired in S804, the AP identification information acquired in S801, the frequency band for communication (2.4 GHz band), and the information acquired in S802 in the AP information storage unit 711. The corresponding frequency band information is stored in association with each other (S805). The control unit 708 stores a frequency band for communication as communication frequency band information.

  Next, when the frequency band to be preferentially communicated is not the 2.4 GHz band (in the case of No in S803), the wireless communication terminal 70 performs communication in the 5 GHz band and grasps the position of the wireless communication terminal 70 ( S807).

  Specifically, the control unit 708 outputs a signal requesting the position information of the wireless communication terminal 70 to the position information determination unit 715. The position information determination unit 715 to which a signal requesting the position information of the wireless communication terminal 70 is input outputs the position information of the wireless communication terminal 70 calculated most recently to the control unit 708. As a result, the control unit 708 acquires the position information of the wireless communication terminal 70. In addition, the control unit 708 stores that the frequency band for communication is the 5 GHz band.

  Next, the control unit 708 stores in the AP information storage unit 711 at least the position information grasped in S807, the AP identification information acquired in S801, the frequency band (5 GHz band) for communication, and the correspondence acquired in S802. The frequency band information is stored in association with each other (S808). The control unit 708 stores a frequency band for communication as communication frequency band information.

  Here, the information group in which the location information, the AP identification information, the frequency band in which communication is performed, that is, the communication frequency band information, and the corresponding frequency band information, stored in the AP information storage unit 711, are as follows: It is referred to as “AP information group with position information”.

  The operation when the AP of the wireless communication terminal 70 is not detected has been described above.

(3) Operation when Detecting AP of Wireless Communication Terminal 70 FIG. 13 is a diagram for explaining the operation when detecting the AP of the wireless communication terminal in the second embodiment of the present invention. It is. Further, FIG. 14 is a diagram for explaining an operation (operation of processing E part in FIG. 13) when detecting an AP of the wireless communication terminal in the second embodiment of the present invention. The operation when an AP is detected will be described with reference to FIGS.

  First, as illustrated in FIG. 13, the wireless communication terminal 70 performs the above-described S600 and determines whether the frequency band in which communication is performed is the 2.4 GHz band.

  Next, when the communication frequency band is the 2.4 GHz band (Yes in S600), the wireless communication terminal 70 performs the above-described S601, and the detected AP is in the 2.4 GHz band or the 5 GHz band. It is confirmed whether it corresponds to both (S1000).

  Specifically, when AP is detected, AP detection section 209 outputs a signal indicating AP detection and AP identification information to control section 708. Next, the control unit 708 acquires the AP information group with position information from the AP information storage unit 711. Further, the control unit 708 acquires corresponding frequency band information corresponding to the input AP identification information from the AP information group. The control unit 708 confirms from the corresponding frequency band information whether the detected AP corresponds to both the 2.4 GHz band and the 5 GHz band.

  Next, when the AP corresponds to both the 2.4 GHz band and the 5 GHz band (Yes in S1000), the above-described “operation when the AP of the wireless communication terminal 20 is not detected” The above-described steps S303 to S306 and S309 to S311 are performed in the same procedure.

  Next, when the AP does not support both the 2.4 GHz band and the 5 GHz band (No in S1000), the wireless communication terminal 70 performs the above-described S604 and performs communication in the 2.4 GHz band. .

  Next, the wireless communication terminal 70 performs the above-described S311 and updates the AP information group with position information and the MAP information when the frequency band for communication is changed to another frequency band (S1001).

  Specifically, when the control unit 708 performs S311 and switches the frequency band for communication to another frequency band, the control unit 708 outputs a signal requesting the position information of the wireless communication terminal 70 to the position information determination unit 715, and The position information of the wireless communication terminal 70 is acquired from the information determination unit 715. The control unit 708 associates the acquired location information, the AP identification information acquired in S1000, the frequency band switched in S311 and the corresponding frequency band information acquired in S1000 with the AP information storage unit 711, and stores the location information. Stored as an attached AP information group. At this time, the control unit 708 stores the frequency band switched in S311 as communication frequency band information. When the same AP identification information as the stored AP identification information has already been stored in the AP information storage unit 711, the control unit 708 updates the information associated with the AP identification information with the stored information. . Furthermore, the control unit 708 updates the MAP information as follows. FIG. 15 is a specific example of the AP information group with position information in the second exemplary embodiment of the present invention.

  (I) First, the control unit 708 acquires an AP information group with position information stored in the AP information storage unit 711. For example, the control unit 708 proceeds with the description assuming that the AP information group with position information in FIG. 15 has been acquired.

  (II) Next, the control unit 708 finds a combination of position information having the same communication frequency band information within a predetermined distance among the position information described in the AP information group with position information. The predetermined distance is set in the control unit 708 by the user of the wireless communication terminal 70 of the present embodiment. For example, if the predetermined distance is set to 1 minute latitude, in the case of FIG. 15, the control unit 708 may have 15 degrees 1 minute east longitude / 15 degrees 1 minute north latitude and 15 degrees 1 minute east longitude / 15 degrees 2 minutes north latitude, Then find two combinations of 30 degrees 2 minutes east longitude 30 degrees 1 minute north latitude and 30 degrees 2 minutes east longitude 30 minutes north latitude 2 degrees.

  (III) Next, the control unit 708 obtains each position information, that is, an area including longitude and latitude, for each combination found in (II). For example, in the case of a combination of position information (15 degrees 1 minute east longitude / 15 degrees 1 minute north latitude) and position information (15 degrees 1 minute east longitude / 15 degrees 2 minutes north latitude), the control unit 708 sets east longitude 15 degrees 1 minute / 15 degrees north latitude 1 to 15 degrees east longitude 15 degrees north latitude In the case of a combination of position information (30 degrees 2 minutes east longitude / 30 degrees 1 minute north latitude) and position information (30 degrees 2 minutes east longitude / 30 degrees 2 minutes north latitude), the control unit 708 Find 30 degrees 2 minutes / north latitude 30 degrees 1 minute to east longitude 30 degrees 2 minutes / north latitude 30 degrees 2 minutes.

  (IV) Next, the control unit 708 associates the area obtained in (III) with the communication frequency band information of the position information included in the area, and holds it as MAP information. In the case of FIG. 15, the control unit 708 holds the MAP information shown in FIG.

  In addition, in FIG. 13, when the frequency band in communication is not the 2.4 GHz band (No in S600), the wireless communication terminal 70 performs the above-described S605 and S606 as shown in FIG. Detect AP.

  Next, when detecting the AP, the wireless communication terminal 70 confirms whether the detected AP is compatible with both the 2.4 GHz band and the 5 GHz band (S1002). S1002 is the same operation as S1000.

  Next, when the AP corresponds to both the 2.4 GHz band and the 5 GHz band (Yes in S1002), the wireless communication terminal 70 detects “AP of the wireless communication terminal 20” described above. The above-described steps S401 to S403 and S405 to S407 are performed in the same procedure as that of “No.

  Next, the wireless communication terminal 70 that has performed S407 updates the AP information group with position information and the MAP information (S1003).

  Specifically, when the control unit 708 performs S407 and switches the frequency band for communication to another frequency band, the control unit 708 outputs a signal requesting the position information of the wireless communication terminal 70 to the position information determination unit 715, and The position information of the wireless communication terminal 70 is acquired from the information determination unit 715. The control unit 708 stores, in the AP information storage unit 711, the acquired position information, the AP identification information acquired in S1000, the communication frequency band information indicating the frequency band switched in S407, and the corresponding frequency band information acquired in S1000. Are stored as an AP information group with position information. At this time, if the same AP identification information as the AP identification information to be stored is already stored in the AP information storage unit 711, the control unit 708 updates the information associated with the AP identification information to the information to be stored. To do. Furthermore, the control unit 708 performs (I) to (IV) described above to update the MAP information.

  Note that when the AP does not support both the 2.4 GHz band and the 5 GHz band (No in S1002), the control unit 708 performs the above-described S608 and performs communication in the 5 GHz band.

  Next, when the processing of any of S604, S306, S1001, S608, S403, and S1003 described above is completed, the control unit 708 returns to S600 described above.

  Since other operations are the same as those in the first embodiment, detailed description thereof is omitted.

[Description of effects]
According to the present embodiment, when a wireless communication terminal re-detects a previously detected AP due to movement or the like, if the wireless communication terminal is in a position before movement, the wireless communication terminal determines a frequency band for communication, such as a reception level. It can ask for without doing. The determination of the reception level or the like is S303 to S305, S309 to S305, S400 to S402, S405 to S408, which are operations of the wireless communication terminal of the first embodiment.

  The reason is that the wireless communication terminal of the present embodiment stores the frequency band at the time of communication at the position before moving in association with the position information, and returns the position information when returning to the position before moving. This is because a frequency band in which communication can be performed can be obtained.

[Third Embodiment]
Next, a third embodiment of the present invention will be described.

[Description of configuration]
FIG. 16 is a diagram illustrating a configuration example of a wireless communication system according to the third embodiment of the present invention. The wireless communication system in the third embodiment includes a wireless communication apparatus 1000 and a wireless communication terminal 2000. The wireless communication apparatus 1000 is connected to the wireless communication terminal 2000 via a wireless transmission path. Note that the wireless communication apparatus 1000 may be an access point used in a wireless LAN, and the wireless communication terminal 2000 may be a terminal compatible with the wireless LAN.

  The wireless communication apparatus 1000 is a wireless communication apparatus that can switch the frequency band for communicating with the wireless communication terminal 2000 from the first frequency band to the second frequency band. The wireless communication apparatus 1000 includes a switching preparation unit and a switching execution unit.

  When receiving a request signal for requesting switching to the second frequency band from the wireless communication terminal 2000, the switching preparation unit calculates a certain time and outputs a signal corresponding to the calculated time. In calculating the constant time, the switching preparation unit may calculate the time after a predetermined time from the time when the request signal is received as the constant time. The predetermined time is set in the switching preparation unit by the user of the wireless communication apparatus 1000 of the present embodiment.

  When the signal corresponding to the time is input, the switching execution unit switches the first frequency band for communication to the second frequency band when the time indicated by the signal has elapsed.

  The wireless communication terminal 2000 is a wireless communication terminal capable of switching the frequency band for communicating with the wireless communication apparatus 1000 from the first frequency band to the second frequency band. Wireless communication terminal 2000 includes a control unit and a frequency band switching unit.

  When the control unit determines that the communication quality has deteriorated during communication in the first frequency band, the control unit outputs a request signal for requesting switching to the second frequency band to the wireless communication apparatus 1000.

  When a signal corresponding to time is input, the frequency band switching unit switches the first frequency band for communication to the second frequency band when the time indicated by the signal has elapsed.

[Description of operation]
First, when the communication quality deteriorates during communication in the first frequency band, the control unit of the wireless communication terminal 2000 outputs a request signal requesting the wireless communication apparatus 1000 to switch to the second frequency band. . When the reception level of the signal received in the first frequency band is equal to or lower than a predetermined level, or when the error rate of the received signal is equal to or higher than a predetermined value, the control unit is assumed that an interference wave of a predetermined amount or more has occurred. You may judge. The user of the wireless communication terminal 2000 of the present embodiment sets the predetermined level and predetermined value in the control unit.

  Next, when the switching preparation unit of the wireless communication apparatus 1000 receives the request signal described above from the wireless communication terminal 2000, it calculates a certain time and outputs a signal corresponding to the calculated time. The output destination is the switching execution unit of the wireless communication apparatus 1000 and the frequency band switching unit of the wireless communication terminal 2000. Note that the switching preparation unit may calculate a time at which a predetermined time has elapsed from the time when the request signal is received as a certain time.

  Next, when a signal corresponding to the time is input, the switching execution unit of the wireless communication apparatus 1000 switches the first frequency band for communication to the second frequency band when the time indicated by the signal has elapsed. .

  In addition, when a signal corresponding to time is input, the frequency band switching unit of wireless communication terminal 2000 switches the first frequency band for communication to the second frequency band when the time indicated by the signal has elapsed. .

[Description of effects]
According to the present embodiment, the wireless communication device 1000 and the wireless communication terminal 2000, which are wireless communication devices, can prevent communication from being interrupted for a long time when the frequency band for communication is automatically switched. it can. The reason is that the wireless communication device 1000 and the wireless communication terminal 2000 switch the frequency band at the same time with matching timing.

  The embodiment described above is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention in the implementation stage.

DESCRIPTION OF SYMBOLS 10 Wireless communication apparatus 20 Wireless communication terminal 70 Wireless communication terminal 100 Communication function part 101 Switching preparation part 102 Switching execution part 201 Antenna 202 Distribution part 203 2.4GHz radio | wireless part 204 5GHz radio | wireless part 205 Modulation / demodulation part 206 Reception level measurement part 207 Reception quality measurement unit 208 Control unit 209 AP detection unit 210 Frequency band switching unit 708 Control unit 711 AP information storage unit 712 GPS antenna 713 GPS wireless unit 714 GPS demodulation unit 715 Position information determination unit 1000 Wireless communication device 2000 Wireless communication terminal

Claims (10)

A radio communication terminal capable of switching a frequency band for communicating with an opposing radio communication device from a first frequency band to a second frequency band,
A controller that outputs a request signal for requesting the wireless communication device to switch to the second frequency band when it is determined that communication quality has deteriorated during communication in the first frequency band;
A frequency band switching unit that switches the first frequency band for performing communication to the second frequency band when the time elapses when a signal corresponding to the time is input,
A wireless communication terminal characterized by the above. A reception level measuring unit for measuring a reception level of a signal received in the first frequency band;
A value corresponding to communication quality from a signal received in the first frequency band, i.e., a reception level measuring unit that measures an error rate of the received signal;
The control unit determines that the communication quality has deteriorated when the reception level is equal to or lower than a predetermined level or the error rate is equal to or higher than a predetermined value.
The wireless communication terminal according to claim 1. The frequency band switching unit switches to the second frequency band when a response signal indicating that switching to the second frequency band is possible is returned.
The wireless communication apparatus according to claim 1, wherein the wireless communication apparatus is a wireless communication apparatus. A device detection unit for detecting the wireless communication device;
A GPS function unit that calculates position information based on radio waves received from a GPS (Global Positioning System) satellite;
The control unit associates the frequency band for communication with the position information calculated by the GPS function unit when the device detection unit is detecting the wireless communication device, and stores it as MAP information. When the device detection unit redetects the wireless communication device, the frequency band corresponding to the position information calculated by the GPS function unit at that time is obtained from MAP information, and the frequency band for performing communication To
The wireless communication terminal according to claim 4. The wireless communication device is an access point used in a wireless LAN (Local Area Network).
The wireless communication terminal according to claim 1, wherein the wireless communication terminal is a wireless communication terminal. A wireless communication device capable of switching a frequency band for communicating with an opposing wireless communication terminal from a first frequency band to a second frequency band,
When a request signal for requesting switching to the second frequency band is received from the wireless communication terminal, a switching preparation unit that calculates a certain time and outputs a signal corresponding to the calculated time;
A switching execution unit that switches the first frequency band for performing communication to the second frequency band when the time has elapsed,
A wireless communication apparatus. The switching preparation unit calculates a time when a predetermined time has elapsed from the time when the request signal is received as a constant time,
The wireless communication apparatus according to claim 6. The switching preparation unit measures the noise amount in the first frequency band and the noise amount in the second frequency band when the predetermined condition is met, that is, the noise amount in the second frequency band is Outputting a response signal indicating that switching to the second frequency band is possible when the amount of noise is smaller than that in the first frequency band;
The wireless communication apparatus according to claim 7. A wireless communication system in which a wireless communication terminal and a wireless communication device communicate with each other,
The wireless communication terminal is the wireless communication terminal according to any one of claims 1 to 5,
The wireless communication device is the wireless communication device according to any one of claims 6 to 8.
A wireless communication system. A frequency band switching method for switching a frequency band for communication between a wireless communication terminal and a wireless communication apparatus from a first frequency band to a second frequency band,
When the wireless communication terminal determines that communication quality has deteriorated during communication in the first frequency band, the wireless communication terminal outputs a request signal requesting the wireless communication apparatus to switch to the second frequency band. When the wireless communication device receives the request signal, the wireless communication device calculates a fixed time, outputs a signal corresponding to the calculated time, and sets the first frequency band for communication when the time has elapsed. When the wireless communication terminal receives a signal corresponding to the time, the wireless communication terminal switches the first frequency band for communication to the second frequency band when the time has elapsed. ,
A frequency band switching method characterized by that.

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