JP4048966B2 - Wireless communication apparatus and program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a first communication means for communicating with other devices by sequentially transmitting radio waves in a predetermined frequency band for each time division slot, and periodically transmitting radio waves in a predetermined frequency band. The present invention relates to a wireless communication apparatus and a program including a second communication unit that performs communication with a wireless repeater.
[0002]
[Prior art]
Conventionally, as a communication system including a plurality of communication units connectable to a plurality of communication networks having different communication methods, for example, a PDC communication unit connectable to a PDC communication network and a PHS communication network A cellular phone device including a connectable PHS communication unit is known (see Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-008256
[Problems to be solved by the invention]
By the way, SS (Spread Spectrum) communication system and Bluetooth communication system are generally used as the wireless communication system on the premises.
The SS communication system is capable of two-way communication in an area with a radius of about 240m indoors and an outdoor area of about 1.2km, and is resistant to external noise, and periodically transmits radio signals in a predetermined frequency band. By doing so, communication is performed with an access point (wireless repeater). The Bluetooth communication system is low power and suitable for indoor communication in a relatively narrow range (with a radius of about 10 m), and by transmitting a radio signal of a predetermined frequency band sequentially for each time-division slot to other devices. Communication with (slave) is performed.
[0005]
Here, a frequency hopping type spectrum dispersion method is also adopted for the Bluetooth communication method, and communication is performed while randomly changing (frequency hopping) within a range of 2402 MHz to 2480 MHz every 1 MHz in a time division manner at a time interval of 625 μsec. Like to do. Also in the SS communication method, communication is performed while frequency hopping is performed in the range of 2419 MHz to 2497 MHz. Therefore, assuming that the SS communication method and the Bluetooth communication method are mounted on the wireless communication terminal, both use the same frequency band, so there is a risk of causing radio wave interference and being in a communication disabled state.
An object of the present invention is to prevent interference between a plurality of communication systems even when a plurality of radio communication systems using basically the same frequency band are used.
[0006]
[Means for Solving the Problems]
The wireless communication apparatus according to the present invention provides a first communication unit that performs short-range communication with another apparatus by sequentially transmitting radio waves in a predetermined frequency band for each time division slot while a connection is established and the line is connected. And a second communication means for communicating with a wireless repeater by periodically transmitting radio waves in a predetermined frequency band, wherein a signal is received from the first communication means. If a response signal from another device is not received after being transmitted, it is determined that the signal from the first communication means and the signal from the second communication means are mixed, and the second The communication means periodically performs communication to pause the transmission operation of the first communication means for a predetermined number of slots, and returns to the normal state after pausing the transmission operation for a predetermined number of slots. Send And characterized by including a resume resume means the work, the.
[0007]
Therefore, in the first and third aspects of the present invention, if a response signal from the transmission destination is not received after the wireless signal is transmitted from the first communication means, the signal from the first communication means and the first Judging that the signal from the communication means 2 has interfered, the transmission operation of the first communication means is paused for a predetermined number of slots and then returned to the normal state to resume the transmission operation. Therefore, even if a plurality of different wireless communication systems using substantially the same frequency band are adopted, interference between the plurality of communication systems can be prevented due to radio wave interference.
The first and second communication means may spread and transmit the frequency component of the radio signal in accordance with a frequency hopping type spectrum dispersion method (the invention according to claim 2),
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a block diagram showing the overall configuration of a wireless LAN (local area network) system in this embodiment.
This wireless LAN system is constructed on the premises of a company or the like, and has a host computer 1 as a core. The host computer 1 is connected to a wireless access point 2 via a wired LAN. The wireless access point 2 is a repeater for exchanging packets, and is arranged at a plurality of locations on the premises. Communication between the host computer 1 and the wireless communication terminal 3 is performed via the access point 2 according to the SS (Spread Spectrum) communication method.
[0009]
The wireless communication terminal 3 is a mobile device such as a PDA, and performs wireless communication with the printer 4 according to the Bluetooth communication method. That is, the wireless communication terminal 3 periodically transmits a wireless signal in a predetermined frequency band to transmit and receive an SS communication function with the host computer 1 via the access point 2 and a wireless signal in the predetermined frequency band. It has a Bluetooth communication function for transmitting and receiving to / from the printer (slave) 4 by sequentially transmitting for each time division slot.
[0010]
FIG. 2 is a block diagram showing basic components of the wireless communication terminal 3.
The main CPU 31 is a central processing unit that controls the overall operation of the wireless communication terminal 3 in accordance with an operating system and various application software in the storage device 32. The storage device 32 includes a program storage area and a data storage area, and is configured by a magnetic, optical, semiconductor memory, or a drive system thereof. The recording device 32 may have a configuration in which a removable storage medium such as a CD-ROM or DVD can be mounted in addition to a fixed memory such as a hard disk. The programs and data in the storage device 32 are loaded into a RAM (for example, static RAM) 33 as needed, or the data in the RAM 33 is saved in the storage device 32. The RAM 33 has a program execution area and a work area.
[0011]
In addition to the input device 34 and the display device 35 that are input / output peripheral devices, a Bluetooth communication controller 36 and an SS communication controller 37 are connected to the main CPU 31 via a bus line, and the main CPU 31 is in accordance with an input / output program. Controls their behavior.
The input device 34 is an operation unit that constitutes a pointing device such as a keyboard, a touch panel, or a touch input pen, and inputs character string data and various commands. The display device 35 is a liquid crystal display device that performs full-color display.
[0012]
The Bluetooth communication controller 36 includes a CPU 36-1, a RAM 36-2, a ROM 36-3, a wireless unit 36-4, and a CPU interface unit 36-5, and 2402 MHz to 2480 MHz in a time division manner with a time interval of 625 μsec. Communication is performed while randomly changing (frequency hopping) within the range of 1 MHz.
FIG. 3A is a diagram showing the transmission timing of a print inquiry signal (polling signal) transmitted from the wireless communication terminal 3 to the printer 4 (main unit to slave) during Bluetooth communication. Transmission is output once per slot, for example, every odd slot. FIG. 3B is a diagram showing a response signal (acknowledgment / negative response) from the printer 4 to the wireless communication terminal 3 at the time of Bluetooth communication. The response signal is transmitted at an even slot timing.
[0013]
The SS communication controller 37 includes a CPU 37-1, a RAM 37-2, a ROM 37-3, a radio unit 37-4, and a CPU interface unit 37-5 as components similar to the Bluetooth communication controller 36, and a range of 2419 MHz to 2497 MHz. Communicate with frequency hopping inside.
Here, FIG. 3C is a diagram showing the transmission timing of the BCON signal (connection confirmation signal) transmitted from the wireless communication terminal 3 to the access point 2 at the time of SS communication. Sent out. FIG. 3D is a diagram showing a CTS signal (response signal) transmitted from the access point 2 in response to a connection confirmation signal from the wireless communication terminal 3 during SS communication.
[0014]
As described above, the Bluetooth communication controller 36 performs communication while performing frequency hopping within the range of 2402 MHz to 2480 MHz, and the SS communication controller 37 performs wireless communication while performing frequency hopping within the range of 2419 MHz to 2497 MHz. The possibility of causing signal interference increases. In this case, when the Bluetooth communication controller 36 cannot normally receive the response signal from the printer 4 after transmitting the print inquiry signal (polling signal), the Bluetooth communication controller 36 and the SS communication It is determined that the BCON signal (connection confirmation signal) from the controller 37 has been interfered. In response to the occurrence of the interference, the Bluetooth communication controller 36 pauses the transmission operation of the Bluetooth communication for a predetermined number of slots, and then returns to the normal state to resume the transmission operation.
[0015]
Next, the operation concept of the wireless communication terminal 3 in this embodiment will be described with reference to the flowchart shown in FIG. Here, each function described in the flowchart is stored in the form of a readable program code, and operations according to the program code are sequentially executed. It is also possible to sequentially execute operations according to the program code transmitted via the transmission medium. That is, in addition to the recording medium, an operation specific to this embodiment can be executed using a program / data supplied externally via a transmission medium.
[0016]
FIG. 4 is a flowchart showing the operation on the Bluetooth communication controller 36 side. In this case, when the connection with the printer 4 is established and the line connection is established, the Bluetooth communication controller 36 has two slots to hold the line connection regardless of whether there is transmission data (printing data). A print inquiry signal (polling signal) is sequentially transmitted at a timing of once every time.
First, the Bluetooth communication controller 36 sets a time division time (625 μsec) in a timer (not shown) in the RAM 36-2 (step S1), and then checks whether there is transmission data (step S2).
[0017]
If there is no transmission data (NO in step S2), a polling signal is transmitted to the printer 4 (slave) (step S3), and it is checked whether a response signal is transmitted from the printer 4 (step S4). ) If no response signal is transmitted, it is determined whether the time is up, that is, whether the time division timing has been reached by checking the elapse of the time division time (625 μsec) (step S5). The process returns to step S4 until the timing comes, and a response from the printer 4 is awaited.
If there is transmission data (YES in step S2), a data signal is transmitted to the printer 4 (slave) (step S13), and it is checked whether a response signal is transmitted from the printer 4 (step S13). S4).
[0018]
Here, if the printer 4 is in a printable state, as shown in FIG. 3B, in response to the inquiry from the wireless communication terminal 3, an OK reply (acknowledgement) signal is transmitted. At the timing when the BCON signal (connection confirmation signal) is transmitted on the SS communication controller 37 side (see FIG. 3C), the OK response signal from the printer 4 and the BCON signal from the SS communication controller 37 interfere with each other. May cause interference. FIG. 3E is a diagram showing a reception state on the Bluetooth communication controller 36 side. In the drawing, a portion with a broken line shows a state in which the OK response signal and the BCON signal are mixed. FIG. 3 (F) is a diagram showing a reception state at the access point 2 side during SS communication. In the figure, a portion with a broken line shows a state in which an OK response signal and a BCON signal are mixed. ing.
[0019]
As described above, when radio signal interference occurs between Bluetooth communication and SS communication, the Bluetooth communication controller 36 may normally receive a response signal from the printer 4 even if the time division time has elapsed. Can not. In such a case, on the condition that the line is not disconnected (step S6), the interference occurrence flag for indicating the occurrence of interference in which the radio signal interferes is turned on (step S7). Then, after resetting the time division time (625 μsec) to the timer (step S1), a print inquiry signal (polling signal) is transmitted (steps S2 and S3), but at this time, the interference state continues. If it is in the state, the response signal from the printer 4 cannot be received normally, so the same processing as described above is repeated (steps S1 to S7).
[0020]
Here, when the radio wave interference state is resolved and the OK response signal from the printer 4 can be normally received (YES in step S4), the elapse of time division time (625 μsec) is checked ( Step S8), waiting until the time division timing comes. Here, when the time division timing is reached, it is determined whether or not there is an interference generation flag (step S9). If the interference occurrence flag is not set, the process returns to the first step S1 and resets the time division time (625 μsec) to the timer on the condition that the line is not disconnected (step S10).
[0021]
On the other hand, if the interference occurrence flag is set, in other words, if the radio wave interference state is occurring (YES in step S9), the print inquiry signal (polling signal) is transmitted for a predetermined number of slots. Only pauses (step S11). Note that the pause time in this case is predetermined in consideration of the interference state and the like, and in the example of FIG. After the predetermined number of slots, the interference generation flag is turned off (step S12), and the line is not disconnected (step S10). Then, the process returns to the first step S1 to return to the normal state. To resume transmission operation.
[0022]
As described above, in this embodiment, when the response signal from the printer 4 is not received after the print inquiry signal (polling signal) is transmitted from the Bluetooth communication controller 36, the response signal from the printer 4 and the SS It is determined that the BCON signal from the communication controller 37 has been mixed, and the transmission operation of the Bluetooth communication controller 36 is paused for a predetermined number of slots, and then returned to the normal state to resume the transmission operation. Therefore, even if Bluetooth communication and SS communication using substantially the same frequency band are adopted, interference between Bluetooth communication and SS communication can be prevented by radio wave interference, and Bluetooth communication and SS communication can be prevented. Can be used.
[0023]
In the above-described embodiment, the Bluetooth communication controller 36 pauses the transmission operation for four slots when interference occurs. However, the pause time may be arbitrarily set in consideration of the interference state and the like.
[0024]
On the other hand, a recording medium (for example, a CD-ROM, a floppy disk, a RAM card, etc.) on which a program code for executing each of the above-described units is recorded may be provided to the computer.
That is, a recording medium having a computer-readable program code, and first communication means for performing near field communication with other devices by sequentially transmitting radio waves in a predetermined frequency band for each time division slot And the second communication means for communicating with the wireless repeater by periodically transmitting radio waves in a predetermined frequency band, and after the signal is transmitted from the first communication means If the response signal from the first device is not received, it is determined that the signal from the first communication means and the signal from the second communication means are mixed, and the first communication means transmits the signal. A function for realizing the function of pausing the operation for a predetermined number of slots and the function of resuming the transmission operation of the first communication means for a predetermined number of slots and then returning to the normal state and restarting the transmission operation. You may make it provide the computer-readable recording medium which recorded the program.
[0025]
【The invention's effect】
According to this invention (the invention described in claim 1), when a response signal from the transmission destination is not received after the wireless signal is transmitted from the first communication means, the signal from the first communication means is received. And the signal from the second communication means are determined to be interfering, and after the transmission operation of the first communication means is suspended for a predetermined number of slots, the transmission operation is resumed by returning to the normal state. Therefore, even if a plurality of different wireless communication systems using substantially the same frequency band are employed, interference between the plurality of communication systems can be prevented due to radio wave interference.
[Brief description of the drawings]
FIG. 1 is a block diagram showing the overall configuration of a wireless LAN system.
FIG. 2 is a block diagram showing basic components of the wireless communication terminal 3;
3A is a diagram showing the transmission timing of a print inquiry signal transmitted from the terminal 3 to the printer 4 during Bluetooth communication, and FIG. 3B is a response transmitted from the printer 4 to the terminal 3 during Bluetooth communication. The figure which showed the signal, (C) the figure which showed the transmission timing of the connection confirmation signal transmitted from the terminal 3 at the time of SS communication, (D) shows the response signal transmitted from the access point 2 at the time of SS communication FIG. 5E is a diagram illustrating a reception state on the terminal 3 side during Bluetooth communication, and FIG. 5F is a diagram illustrating a reception state on the access point 2 side during SS communication.
FIG. 4 is a flowchart showing the operation on the Bluetooth communication controller 36 side.
[Explanation of symbols]
1 Host computer 2 Access point 3 Wireless communication terminal 4 Printer 31 Main CPU
32 storage device 34 input device 35 display device 36 Bluetooth communication controller 37 SS communication controller 37

Claims (3)

A first communication means for performing near field communication with another device by sequentially transmitting radio waves in a predetermined frequency band for each time division slot during connection and establishing a connection ; A wireless communication device comprising a second communication means for communicating with a wireless repeater by periodically transmitting;
If a response signal from another device is not received after the signal is transmitted from the first communication means, the signal from the first communication means and the signal from the second communication means are mixed with each other. A pause unit that periodically performs communication by the second communication unit and pauses the transmission operation of the first communication unit by a predetermined number of slots;
Resumption means for resuming the transmission operation by resuming the transmission operation by a predetermined number of slots and resuming the transmission operation by the pause means;
A wireless communication apparatus comprising: The first and second communication means spread and transmit a frequency component of a radio signal in accordance with a frequency hopping type spectrum dispersion method;
The radio communication apparatus according to claim 1, wherein the radio communication apparatus is configured as described above. A first communication means for performing near field communication with another device by sequentially transmitting radio waves in a predetermined frequency band for each time division slot during connection and establishing a connection ; A computer of a wireless communication device comprising a second communication means for communicating with a wireless repeater by periodically transmitting ;
If a response signal from another device is not received after the signal is transmitted from the first communication means, the signal from the first communication means and the signal from the second communication means are mixed with each other. A pause unit that periodically performs communication by the second communication unit and pauses the transmission operation of the first communication unit by a predetermined number of slots ;
Resume means for resuming the transmission operation by returning to the normal state after the transmission operation is suspended by the predetermined number of slots by the pause means.
Program to function as .

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