JPH07327255A - Communication equipment - Google Patents

Abstract

PURPOSE:To reduce the radio error by selecting communication channels, by which radio communication between a master machine and a slave machine is performed, in accordance with the priority order determined by the frequency in communication error. CONSTITUTION:The priority level of each communication channel and the frequency in communication error during communication using the communication channel are stored in a storage part 13. Priority levels are determined in the descending order of the frequency in communication error. In the case of radio transmission from a master machine 10 to a slave machine 20, 30, or 40, a control part 12 selects the communication channel of a frequency band to be used by the priority levels stored in the storage part 13 and indicates it to a radio part 17, and the radio part 17 performs radio transmission by this communication channel. In the case of transmission from the slave machine 20, 30, or 40 to the master machine 10, the master machine 10 selects the communication channel to be used by priority levels in the storage part 13 and reports it to the slave machine 20, 30, or 40 and starts radio communication to the slave machine 20, 30, or 40 by this communication channel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication device for selecting a frequency band used for wireless communication based on priority.

[0002]

2. Description of the Related Art There has been developed a communication device in which a fixed telephone or a master unit in which a telephone and a facsimile device are integrated with each other is used as a slave unit in which the telephone or the facsimile device is a slave unit. The child machine can be freely moved and used in small areas such as indoors. In this method, all assigned wireless channels are commonly used by a plurality of cordless telephones, and an available channel is selected and used.

[0003]

In such wireless communication, when the output frequency is small and there is an electronic device or the like that generates harmonics in the surroundings, when a channel in the corresponding frequency band is used, noise becomes large and normal Communication cannot be performed and a communication error occurs.

The present invention has been made in view of the above problems, and an object of the present invention is to reduce communication errors by selecting a communication channel in which wireless communication errors are less likely to occur. Further, it is an object of the present invention to always store a channel having a small number of wireless communication errors based on the communication results and use this to reduce the communication errors.

[0005]

To achieve the above object, in order to achieve the above-mentioned object, a wireless unit for wirelessly communicating with a terminal, a line connected to a line, data transmitted by the wireless unit is transmitted to the line, and data received from the line is transmitted by the wireless unit. The wired communication unit to be transmitted to the terminal, the storage unit that stores the priority order for each communication channel to which different radio frequency bands are assigned, and the wireless unit that is used based on the priority order of the storage unit when wirelessly communicating with the terminal Channel selection means for selecting a communication channel to be used.

[0006] Further, the wireless unit which wirelessly communicates with the terminal and the wired communication unit which is connected to the line and transmits the data received by the wireless unit to the line and causes the data received from the line to be transmitted to the terminal by the wireless unit are different from each other. A storage unit that stores a priority order for each communication channel to which a radio frequency band is assigned, and a channel selection unit that selects a communication channel used by the radio unit based on the priority order of the storage unit when wirelessly communicating with a terminal, Means for measuring the communication error frequency of the communication channel used when wirelessly communicating with the terminal and rewriting the priority order based on the measured communication error frequency.

Further, the channel selecting means does not select a communication channel whose communication error frequency is higher than a predetermined value.

Further, the channel selecting means selects from the communication channels having a high priority, and when all the communication channels stored in the storage section are in use, waits for a certain period of time and then again gives priority to the communication channels. The communication channel is selected from high communication channels.

[0009]

Since the communication channel for wireless communication with the terminal is selected based on the priority order stored in the storage unit,
By setting the priorities in the order of least communication error, it is possible to select a communication channel that is less likely to cause a communication error as compared with the conventional case of selecting a vacant frequency band.

Further, since the communication error frequency of the communication channel used is detected and the priority of the communication channel is rewritten based on this, even if the communication error generated by the communication channel changes due to a change in the environment, Correspondingly, it is possible to select a communication channel with less communication error.

Further, since the communication channel whose communication error frequency is higher than a predetermined value is not used, the occurrence of communication error can be reduced.

When selecting a communication channel, a communication channel with a high priority is selected. When all communication channels are in use, a communication channel with a high priority is selected again after waiting for a certain period of time. As a result, communication errors can be reduced.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. In FIG. 1, the communication device includes a master unit 10, a telephone slave unit 20, a FAX slave unit 30, and a telephone FAX combined slave unit 40. In the base unit 10, the network control unit 11
Is connected to a telephone line and controls telephone and facsimile (hereinafter referred to as FAX) communication with a communication partner. The control unit 12 controls the entire base unit 10 and operates as a channel selection unit that selects communication channels to which different frequency bands are assigned according to the priority, a unit that measures the communication error frequency and rewrites the priority. The storage unit 13 stores the priority order of each communication channel, and the control unit 12 reads and rewrites the priority order. The modem section 14 performs modulation / demodulation for transmitting / receiving image data via a telephone line, and the FAX signal control section 15 has a memory and controls the modem section 14. The signal switching unit 16 receives the FAX signal from the modem unit 14 or moving away from the modem unit 14, and the network control unit 12
Switch the audio signal to or from there. Radio unit 17
Transmits to the slave unit on the communication channel selected by the control unit 12 and transmits the data received from the slave unit to the signal switching unit 16.

The telephone slave unit 20 has a radio unit 21 for performing radio communication with the base unit 10, a telephone unit 22 for transmitting / receiving a voice signal to / from the radio unit 21, and a handset 23 for making a call via the telephone unit 22.
And a control unit 24 that controls the entire telephone slave unit 20. The FAX slave device 30 has a wireless unit 31 that wirelessly communicates with the master device 10, and a FAX unit that transmits and receives a FAX signal to and from the wireless unit 31.
Unit 32, a recording / reading unit 33 that records an image signal from the FAX unit 32, reads a document image, and sends the image signal to the FAX unit 32, and a control unit 34 that controls the entire FAX subunit 30. To be done.

The telephone FAX combined use handset 40 includes a radio unit 41 for performing radio communication with the base unit 10, a signal switching unit 42 for switching between a voice signal and a FAX signal, and a telephone unit 43 for transmitting / receiving a voice signal to / from the radio unit 41. A handset 44 for making a call via the telephone unit 43 and an F for transmitting / receiving a FAX signal to / from the wireless unit 41.
It is composed of an AX unit 45, a recording / reading unit 46 for recording an image signal from the FAX unit 45, reading an original image and sending it to the FAX unit 45, and a control unit 47 for controlling the entire telephone FAX / combined handset 40. It

Next, the operation for telephone communication and FAX communication will be briefly described. First, there is an incoming call from the telephone line, the network control unit 11 detects this and detects the presence or absence of the CNG signal representing the FAX signal in the input signal, and if the CNG signal is detected, the transmitted FAX signal Is demodulated by the modem unit 14, temporarily stored by the FAX signal control unit 15, modulated by the wireless unit 17, and sent to the FAX subunit 30 or the telephone FAX combined subunit 40. The FAX slave unit 30 or the telephone FAX combined slave unit 40 receives and demodulates by the wireless units 31 and 41, and temporarily stores them in the FAX units 32 and 45, and the recording / reading unit 33,
Record at 46. If no CNG signal is detected,
The voice signal is modulated by the wireless unit 17 and transmitted to the telephone subunit 20 or the telephone FAX combined subunit 40. The telephone subunit 20 or the telephone FAX combined subunit 40 is received and demodulated by the wireless units 21 and 41, and the telephone It is sent from the units 22 and 43 to the handsets 23 and 44 and output as voice. In addition, FAX handset 30 and telephone FAX
The master unit 10 gives an instruction as to which of the dual-purpose slave units 40 receives the signal.

When a telephone call is made from the telephone slave unit 20 and the telephone FAX / combined cordless handset 40, the signal is transmitted by off-hooking the handsets 23 and 44 and dialing.
2, 43, and the radio units 21 and 41 to transmit the data to the base unit 10 and the network control unit 11 to the telephone line. When the other party's telephone answers, the line is connected and the call becomes possible. Further, when FAX transmission is performed from the FAX slave unit 30 and the telephone FAX combined use slave unit 40, the FAX signal is transmitted by setting the transmission document from the recording / reading units 33 and 46.
2, 45, and is transmitted to the base unit 10 through the radio units 31 and 41, and sent from the network control unit 11 to the telephone line. Opponent FAX
The line is connected when the machine responds, and the FAX slave unit 3
0, recording / reading unit 33, 46 of telephone FAX combined use slave unit 40
The transmission original is read from and the image signal is transmitted to the FAX section 32, 4
5, transmitted to the base unit 10 through the wireless units 31 and 41.
The base unit 10 receives the image signal through the wireless unit 17, and
After being processed by the X signal control unit 15, the modem unit 14 modulates and transmits to the telephone line.

Next, the operation of this embodiment will be described. In the present embodiment, when the master device 10 wirelessly communicates with the slave devices 20, 30, and 40, which frequency band is used to select a communication channel to be selected. The storage unit 13 shows the priority order for each communication channel as shown in FIG. 2 and the communication error frequency in the communication performed by each communication channel. The priority order is determined in the ascending order of communication error frequency. The communication error frequency Er is expressed by the following equation (1). Er = 100 × (number of retransmitted frames) / total number of communication frames (1) Here, when the same frame is retransmitted many times, 100%
It also occurs when it exceeds. A frame is a unit for communication, and error detection is performed for each frame.

When wirelessly transmitting from the master unit 10 to the slave units 20, 30, and 40, the control unit 12 selects the communication channel of the frequency band to be used according to the priority order stored in the storage unit 13 and instructs the wireless unit 17. Then, the wireless unit 17 wirelessly transmits using this communication channel. On the other hand, when wirelessly transmitting from the slaves 20, 30, 40 to the master 10, the slaves 20, 30, 40 transmit using a communication channel of a predetermined frequency band. When the master device 10 receives this, the slave devices 20, 30,
40 recognizes that the wireless communication will be started, selects the communication channel to be used from the priority order of the storage unit 13, and
0, 30, 40 are notified, and the cordless handset 2 is used on this communication channel.
Start wireless communication with 0, 30, 40. In this way, the base unit 10 is always configured to determine the communication channel for wireless communication between the base unit 10 and the handset units 20, 30, 40. It is to be noted that the predetermined communication channels used by the slave units 20, 30, 40 at the time of the first call are several channels, and the usable time is limited to about one second.

FIG. 3 is a flow chart of communication channel selection when wireless communication is performed. When starting the wireless communication, when transmitting from the master device 10 to the slave devices 20, 30, 40, the control unit 12 moves to the next step, but when transmitting from the slave devices 20, 30, 40 to the master device 10, A signal to be wirelessly transmitted through a predetermined communication channel is transmitted from the slaves 20, 30, and 40, whereby the control unit 12 moves to the next step (ST1).
The control unit 12 of the parent machine accesses the storage unit 13, checks the priority order shown in FIG. 2 (ST2), and selects the communication channel having the first priority order (ST3). It is checked whether the selected communication channel is not used for other communication and is vacant (ST4), and if it is vacant, the communication channel is set to the wireless unit 1.
Notify 7. When there is communication from the slaves 20, 30, and 40 indicating that wireless communication is desired on the predetermined communication channel, the wireless unit 17 communicates this communication channel to the slaves 20, 30, and 40. Thereby, the communication channel for wireless communication is determined, and the communication process is performed (ST5).

If no communication channel is available in ST4, it is checked whether there is a communication channel with the next priority (ST
6) If there is, the communication error frequency Er of the communication channel is checked (ST7), and if it is less than or equal to a predetermined value, the communication channel of that priority is selected (ST8). Next, returning to ST4, it is checked whether or not the communication channel is vacant. If it is vacant, the process proceeds to ST5, and if it is not vacant, the process proceeds to ST6. If the communication error frequency is equal to or higher than the predetermined communication error in ST7, or if there is no communication channel with the next priority in ST6, after waiting for a predetermined time (ST9), the communication channel with the priority 1 is selected from the beginning (ST3). ).

FIG. 4 is a detailed flow chart of the communication process (ST5) of FIG. When the communication channel is selected, wireless communication is performed between the master device 10 and the slave devices 20, 30, and 40 using this (ST51). When the wireless communication ends, the control unit 12
Counts the number of error frames (ST52), calculates the communication error frequency using equation (1) (ST53), and rewrites the priority order shown in FIG. 2 based on this result (ST54). In this way, each time wireless communication is performed, the priority order is updated based on the communication result, so that it is possible to always grasp the state of the latest communication channel and select a communication channel with few communication errors.

[0024]

As is apparent from the above description, according to the present invention, the communication channel for wireless communication between the master unit and the slave unit is selected according to the priority order determined in the ascending order of the communication error. can do. Further, since the frequency of occurrence of communication error is measured for each wireless communication and the priority order is updated, the communication channel can be selected according to the change in environment. Further, the occurrence of communication errors can be reduced by avoiding the use of communication channels in which the frequency of occurrence of communication errors is greater than or equal to a predetermined value.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing a table representing a priority order of communication channels stored in a storage unit.

FIG. 3 is an operation flow chart of this embodiment.

FIG. 4 is a detailed flowchart of the communication process of FIG.

[Explanation of symbols]

 10 parent unit 11 network control unit 12, 24, 34, 47 control unit 13 storage unit 14 modem unit 15 FAX communication control unit 16, 42 signal switching unit 17, 21, 31, 41 wireless unit 20 telephone slave unit 22, 43 telephone Part 23,44 Handset 30 FAX handset 32,45 FAX part 33,46 Recording / reading unit 40 Telephone FAX combined handset

Claims (4)

[Claims] 1. A wireless unit that wirelessly communicates with a terminal, and a wired communication unit that is connected to a line and transmits data received by the wireless unit to the line and causes the data received from the line to be transmitted to the terminal by the wireless unit are different from each other. A storage unit that stores a priority order for each communication channel to which a radio frequency band is assigned, and a channel selection unit that selects a communication channel used by the radio unit based on the priority order of the storage unit when wirelessly communicating with a terminal, A communication device comprising: 2. A wireless unit that wirelessly communicates with a terminal, and a wired communication unit that is connected to a line and transmits data received by the wireless unit to the line and causes the data received from the line to be transmitted to the terminal by the wireless unit are different from each other. A storage unit that stores a priority order for each communication channel to which a radio frequency band is assigned, and a channel selection unit that selects a communication channel used by the radio unit based on the priority order of the storage unit when wirelessly communicating with a terminal, A communication device, comprising: a unit that measures a communication error frequency of a communication channel used when wirelessly communicating with a terminal and rewrites the priority order based on the measured communication error frequency. 3. The communication device according to claim 2, wherein the channel selecting means does not select a communication channel whose communication error frequency is higher than a predetermined value. 4. The channel selecting means selects from communication channels having a high priority, and when all the communication channels stored in the storage unit are in use, waits for a certain period of time and then prioritizes again. The communication device according to claim 2, wherein the communication device is selected from a communication channel having a high communication rate.