JPH11341554A - Device and method for selecting frequency channel in communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the device and the method that relax a long time scanning of an idle frequency channel attended with increased number of frequency channels in the radio communication equipment and that relax increase in time when communication is made available due to the long scanning time. SOLUTION: The radio communication equipment with a higher probability of decreasing a scanning time of an idle channel is provided by providing a storage device 17 that stores frequency channel information used by the radio communication equipment 11 for communication till at least a succeeding communication and a controller 16 that reads frequency channel information stored in the storage device 11 at next communication and sets first scanning of a frequency channel of the frequency channel information in the scanning of the idle frequency channel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for selecting a frequency channel of a communication apparatus.
The present invention relates to a method of improving a selection time in a method of selecting a frequency channel of a communication device and an apparatus therefor.

[0002]

2. Description of the Related Art With the recent liberalization of communications, the spread of wireless communication devices has been progressing at a very high speed.
It is also being used for data communication including voice and video, but with the spread of such communication devices, the number of channels has been increasing, and as a result, the frequency band used has increased. The number of channels is also increasing. As a conventional method of selecting a frequency channel of a wireless communication device using a large number of frequency channels, a method of sequentially scanning a received signal to scan an available frequency channel or a frequency channel that can be used using random number table data or the like is used. There is known a random access scan for randomly extracting and scanning the data. Regardless of which scan is used, the scan ends when an empty frequency channel is scanned, and communication is performed in the wireless communication device using the empty frequency channel. Hereinafter, a conventional wireless communication device will be described with reference to FIG. The wireless communication device 1 is a multi-channel access type wireless communication device, such as a mobile phone device or a PHS, for scanning a radio frequency channel to be used to find an empty channel at the start of use. The antenna 2 is connected to a transmitting / receiving device 3 to be described later, radiates and transmits a radio signal from the transmitting / receiving device 3, and receives and supplies the radio signal to the transmitting / receiving device 3. Transceiver 3
Is connected to the antenna 2 and a control device described below, and includes a reception sensitivity detection unit 4 and a reception signal quality detection unit 5 described below.
The transmission / reception device 3 modulates a low-frequency signal such as a voice signal or a terminal data signal into a high-frequency signal that can be transmitted wirelessly, transmits the high-frequency signal from the antenna 2, demodulates a radio signal received by the antenna 2, and This is for obtaining data and the like. The reception sensitivity detection unit 4 detects the electric field strength of the signal received in the transmission / reception device 3, and detects whether the electric field strength is sufficient to demodulate and reproduce the received signal.

[0005] The received signal quality detecting section 5 detects deterioration of signal quality due to noise or waveform distortion of a signal received in the transmitting / receiving apparatus 3. The control device 6 is connected to the transmission / reception device 3, the storage device 7, and the communication start switch 8, receives a signal from each device and the like, and supplies a control signal to those devices as needed. In addition, the above processing controls the entire wireless communication apparatus 1 so that transmission and reception for communication with the partner station can be performed, and an empty channel can be obtained by sequential scanning or random access scanning. The storage device 7 is connected to the control device 6 and stores signals required for wireless communication such as the ID number of the wireless communication device 1 and, for example, frequencies of wireless frequency channels from 1 to n channels. The communication start switch 8 is a switch that is connected to the control device 6 and that is turned on when the owner of the wireless communication device 1 attempts to start communication. When the owner of the wireless communication device 1 turns on the communication start switch 8, confirms a received signal addressed to the wireless communication device 1, or detects that the received signal condition has deteriorated, the control device 6 stores the received signal. A free channel is sequentially scanned or random access scanned from the frequency channel data from 1 to n stored in the device 7. For example, consider the case where the number of channels allocated to the wireless communication device 1 is 5 and the communication start switch 8 is turned on by the owner.
The free channels are scanned in the order of 3, 4, and 5. If a free channel is found, communication is started on that channel. If no free channel is found, scanning is performed again, and scanning is repeated to find a free channel.

[0004]

However, in order to determine whether one frequency channel is empty or in use, it is necessary to stay in that channel for a certain period of time during scanning. However, it is difficult to reduce the time required for scanning, and in the conventional wireless communication apparatus, the time required for scanning an empty frequency channel becomes nonnegligible due to an increase in the frequency band used and an increase in the number of channels. I have. The problem to be solved by the present invention is to lengthen the scan time of an empty frequency channel due to the increase in frequency channels in such a wireless communication device, and to increase the time until communication becomes possible due to the increase in the scan time. It is to provide an apparatus and a method for mitigating the increase.

[0005]

According to the first aspect of the present invention, it is detected that the communication has started or the reception signal condition has deteriorated, and an idle frequency channel has been set for a number of frequency channels set. In a communication device that performs scanning and performs communication using the free frequency channel, a storage device that stores frequency channel information used in communication by the communication device at least until the next communication of the communication device; A control device for reading out the frequency channel information stored in the storage means during communication, and setting the frequency channel of the frequency channel information to be scanned first in the scan of the vacant frequency channel. According to the first aspect of the present invention, a storage device for reading out information of a frequency channel used in the previous communication at the start of communication or when a received signal state is deteriorated, and the frequency is first used by using the previous frequency channel information. By using a control device that scans a channel to perform an idle channel scan, it is possible to provide a communication device that has a high probability of shortening the scan time of an idle channel. According to the second aspect of the present invention, it is detected that communication has started or the reception signal condition has deteriorated, and a scan is performed for a number of frequency channels that have been set, and the available frequency channels are scanned. In a communication device that performs communication using, a storage device capable of storing the frequency channel information used by the communication device for the latest predetermined number of communications, and a storage device for each frequency channel used for the latest predetermined number of communications. A storage device capable of storing usage frequency information, and when scanning the empty frequency channel, read out the frequency channel information and usage frequency information stored in the storage means, and A control device for setting the scanning order of the frequency channels and scanning the empty frequency channels. According to the second aspect of the present invention, when the communication starts or when the reception signal condition deteriorates, the storage device reads out the frequency channel information used in the previous communication and the number of times of use of each frequency channel, and uses the information by using the information. By using a control device that scans these frequency channels in the order of frequency to scan an empty channel, it is possible to provide a communication device that has a high probability of shortening the scan time of the empty channel.

According to the third aspect of the present invention, it is detected that the communication has started or the reception signal condition has deteriorated, and a scan is performed for a number of frequency channels that have been set, thereby searching for available frequency channels. In a communication device that performs communication using an available frequency channel, a process in which frequency channel information used by the communication device for communication is stored in storage means at least until the next communication of the communication device; A step of reading the frequency channel information stored in the storage means, and a step of setting the frequency channel of the frequency channel information to be scanned first in the scan of the empty frequency channel. According to the third aspect of the present invention, when communication starts or when the received signal state deteriorates, information on the frequency channel used in the previous communication is read from the storage device, and the control device first uses the previous frequency channel information to read the information. By performing frequency channel scanning to perform idle channel scanning, it is possible to provide a communication device that has a high probability of shortening the idle channel scanning time. In the invention according to claim 4,
In a communication device that detects that communication has started or that the received signal state has deteriorated, scans a number of frequency channels that have been set for available frequency channels, and performs communication using the available frequency channels. Storing the frequency channel information used by the communication device in the latest predetermined number of communications in the storage means, and storing the frequency information in each frequency channel used in the latest predetermined number of communications in the storage means. And the step of reading out the frequency channel information and the number of times of use information stored in the storage means when scanning the empty frequency channel, and the step of reading out the frequency channel information in descending order of the frequency of use of the number of times of use information. And the step of setting the scanning order of the frequency channels and scanning the unused frequency channels. According to the fourth aspect of the present invention, at the start of communication or when the reception signal condition deteriorates, the storage device reads out the frequency channel information used in the previous communication and the number of times of use of each frequency channel, and the control device reads the information. By scanning the frequency channels in order of frequency of use to perform the idle channel scanning, it is possible to provide a communication device that has a high probability of shortening the scan time of the idle channel.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an overall configuration of an embodiment according to the present invention. Wireless communication device 11
Is a wireless communication device capable of transmitting and receiving multi-channel access type voice or data at the start of use, which scans a radio frequency channel to be used to find an empty channel, similarly to the wireless communication device 1 of the related art. For example, a mobile phone device, a PHS, or the like. The antenna 12 is for transmitting and receiving a voice signal, a terminal data signal, and the like from the mobile phone device 1 wirelessly, similarly to the antenna 2 of the related art, and is connected to the transmitting / receiving device 13.
The radio signal is radiated from the transmitting / receiving device 13 and transmitted, and the radio signal is received and supplied to the transmitting / receiving device 13. For example, a rod antenna or a helical antenna is used. The transmission / reception device 13 modulates a voice signal or a data signal into a radio signal by using a double superheterodyne method or the like and converts it into a transmission frequency signal to transmit to the antenna 12, similarly to the transmission / reception device 3 of the related art described above. And demodulates the radio frequency signal received from the receiver into an audio signal, a data signal, or the like. The reception sensitivity detection unit 14 detects the electric field strength of the signal received by the antenna 12 and the like, as in the reception sensitivity detection unit 4 of the related art, so that the reception signal has sufficient strength to demodulate and reproduce the reception signal. Is detected. The reception signal quality detection unit 15 detects deterioration of signal quality due to noise or waveform distortion of a signal received by the antenna 12, similarly to the reception signal quality detection unit 5 of the related art. The control device 16 can control the whole wireless communication device 1 to perform transmission and reception for communication with a partner station, similarly to the control device 6 of the related art, and sequentially scan or randomly scan for available channels. A channel scanning order setting unit 21 that can be obtained by access scanning and that can reset the order of channel scanning using data stored in the storage device 17 described later is provided. The control device 16 is connected to the transmission / reception device 13, the storage device 17, the communication start switch 18, and the like, receives signals from the respective devices and the like, and supplies control signals to those devices as necessary.
When an empty channel is found by the frequency channel scanning, the channel is stored in the used channel number storage unit 22 of the storage device 17, and the number of recent use of the channel is counted and stored in the used frequency storage unit 23 of each channel of the storage device 17. Let it.

The storage device 17 stores the ID number of the wireless communication device 1 and, for example, 1 like the storage device 7 of the prior art.
An area for storing signals necessary for wireless communication such as frequencies of radio frequency channels from channel n to channel n, and an area for storing a channel number used when this wireless communication apparatus 11 was used last time; For example, a nonvolatile memory such as a flash memory or a volatile memory such as a RAM backed up by a battery has an area for storing how many times the used channel has been used in recent use. The communication start switch 18 is a switch that is turned on when the owner of the wireless communication device 11 attempts to start communication, similarly to the communication start switch 8 of the related art. The channel scanning order setting unit 21 can set the order of scanning by using information stored in a use channel number storage unit 22 and a use count storage unit 23 for each channel, which will be described later, in the control device 16. The used channel number storage unit 22 is a storage unit that is paired for each channel number with a later-described usage count storage unit 23 for each channel in the storage device 17, and the frequency channel used in the latest predetermined number of communications. Or the frequency itself used for communication is stored. The number-of-uses storage unit 23 for each channel is a storage unit paired with the use channel number storage unit 22 for each channel number in the storage device 17,
In the channels stored in the used channel number storage unit 22, the number of times each channel has been used in the latest predetermined number of communications is stored.

The operation of the wireless communication device will be described below. When the owner of the wireless communication device 11
8 is turned on, the received signal addressed to the wireless communication device 11 is confirmed, or when the received signal condition is detected to be deteriorated, the control device 16 stores the received signal in the used channel number storage unit 22 of the storage device 17. From available data to data of the used frequency channel up to the previous communication, the available channels are sequentially scanned from the frequency channel data of 1 to n or the frequency channel of the data of the used frequency channel is scanned before random access scanning. I do. When the number of times of use is stored for each channel, scanning is performed by setting the order of scanning in descending order of the number of times of use. If a free channel is found, communication is started on that channel. If not found, scanning is performed again, and scanning is repeated to find a free channel.

FIG. 2 is a flowchart showing an example of the frequency channel selection method according to the embodiment of the present invention.
Step S1 is a step of determining whether or not channel scanning is necessary. The communication start switch 18 is turned on, or the reception sensitivity detection unit 14 or the reception signal quality detection unit 15 detects the deterioration of the state of the reception signal. Case (Step S1: Y
ES), the process proceeds to the next step S2. If the reception sensitivity detector 14 and the received signal quality detector 15 cannot detect the deterioration of the state of the received signal even when the communication start switch 18 is turned on (step S1: NO). Then, the determination in step S1 is repeated again. In step S2, the information of the used channel number storage unit 22 in which the previous used channel of the used radio communication apparatus 11 or the latest predetermined number of used channels and the like are stored, and the use of each channel which is the storage of the number of times of use of the channel. The information in the number-of-times storage unit 23 is read into the channel scanning order setting unit 21 of the control device 16. In step S3, based on the information obtained in step S2, the channel scanning order setting unit 2
1 sets the scanning order of the channels. The information stored in the number-of-uses storage unit 23 for each channel is replaced in descending order of the number of uses, and the scanning order of the channels in the used channel number storage unit 22 is determined. Here, for example, when updating the information of the used channel number storage unit 22 and the information of the used frequency storage unit 23 for each channel in step S7 described later, when updating can be performed so as to store the information in descending order of the number of used times Only needs to set the information read in step S2 as it is. In step S4, scanning of frequency channels is performed in the order set in step 3 above. In step S5, it is determined whether an empty channel has been detected in the scanning of the frequency channel in step S4, and if an empty channel has been detected (step S5:
If YES, the process proceeds to step S7, and if no empty channel is detected (step S5: NO), the process proceeds to step S6.

In step S6, the number of frequency channel scans is counted, and it is determined whether the number has reached a predetermined number. If the number of scans has reached the predetermined number (step S6: YES), the process proceeds to step S9. If the number of scans has not reached the predetermined number (step S6: NO),
Returning to step S4, the scanning is repeated. The scanning of the frequency channel is basically repeated until a vacant channel is detected. However, outside the service area or the like, a problem occurs in that the scanning is repeated without any vacant channel being detected and the battery or the like is wasted. Therefore, the number of scans is set in advance, and when the number of scans reaches the number,
It notifies the user that communication is not possible. In step S7, the unused channel obtained by the scanning is determined as the used channel, and the used channel data is used to store the information of the used channel number storage unit 22 and the number of use times storage unit for each channel, which stores the number of use times of the channel. 23 information is updated. As a method of updating the storage of the used channel number storage unit 22 and the number of use times storage unit 23 for each channel, for example, a method of storing the number of use times in the order of the channel number and updating the channel information each time it is used. Each time the channel is used, 1 is added to the corresponding channel of the information of the number-of-uses storage unit 23 for each previous channel, and the information is rearranged and stored including the information of the used-channel number storage unit 22 in descending order of the number of times of use. A method is conceivable. In the latter case, the scanning order may be determined in the order of the stored information without rearranging the channels in the setting of the scanning order in step S3.

In step S8, communication is performed using the used channel determined in step S7. In step S9, if an empty channel is not detected even after performing frequency channel scanning a predetermined number of times in step S6, a communication disabled message is displayed and notified to the user.
By doing so, the frequency channel information used for communication and the number of times of use of each channel are stored,
By using the information at the time of the next communication or at the time of deterioration of the signal state, it becomes possible to detect a vacant channel earlier than normal scanning, and to quickly shift to the reception state.
Although the present embodiment has been described as a wireless communication device using an antenna and a radio wave, the present invention is not limited to this, and it is possible to perform multi-channel communication in any communication using electromagnetic waves such as visible light, infrared light, and X-rays. The present invention can be applied to an access type transceiver or a multi-channel access type transceiver using a combination of them. In the above-described embodiment, the wireless system has been described. However, the present invention is also applicable to a transceiver of a wired multi-channel access system. Is stored and provided in a storage device incorporated in the wireless communication device, but may be supplied as information stored on a separately separable storage card or the like, or a frequency channel may be supplied from a communication partner or a base station. Information may be received. In the present embodiment,
Although shown as a wireless communication device, the present invention can be applied to any communication device or receiver that performs transmission or reception in a multi-channel access method.

[0013]

As described above, the present invention has the following excellent effects. According to the first aspect of the present invention, a storage device for reading out information on the frequency channel used in the previous communication at the time of starting communication or when the received signal state deteriorates, and using the frequency channel information of the previous time, By using a control device that scans the frequency channel to perform an idle channel scan, it is possible to provide a wireless communication device that has a high probability of shortening the scan time of the idle channel. According to the second aspect of the present invention, when the communication starts or when the reception signal condition deteriorates, the storage device reads out the frequency channel information used in the previous communication and the number of times of use of each frequency channel, and uses the information by using the information. By using a control device that scans these frequency channels in order of frequency to scan an empty channel, it is possible to provide a wireless communication device that has a high probability of shortening the scan time of the empty channel. According to the third aspect of the present invention, when communication starts or when the received signal state deteriorates, information on the frequency channel used in the previous communication is read from the storage device, and the control device first uses the previous frequency channel information to read the information. By performing frequency channel scanning to perform idle channel scanning, it is possible to provide a wireless communication apparatus that has a high probability of shortening the scanning time of empty channels. According to the fourth aspect of the present invention, at the start of communication or when the reception signal condition deteriorates, the storage device reads out the frequency channel information used in the previous communication and the number of times of use of each frequency channel, and the control device reads the information. By scanning the frequency channels in order of use frequency to perform the idle channel scanning, it is possible to provide a wireless communication apparatus having a high probability of shortening the idle channel scanning time. By doing so, even if the frequency channels used increase, the scanning is performed from the frequency channels that have a good radio wave condition, so that the time until an empty frequency channel is detected is shortened. As a result, communication can be performed without increasing the average time until communication becomes possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of an embodiment of an overall configuration of a wireless communication device according to the present invention.

FIG. 2 is a diagram illustrating an example of a frequency channel selection method according to the embodiment of the present invention.

FIG. 3 is a diagram illustrating an overall configuration of a conventional wireless communication device.

[Explanation of symbols]

1, 11: wireless communication device, 2, 12: antenna, 3, 13: transmission / reception device, 4, 14: reception sensitivity detection unit, 5, 15: reception signal quality detection unit,
6, 16 ... control device, 7, 17 ... storage device, 8, 18 ... communication start switch, 21 ...
Channel scanning order setting unit, 22: used channel number storage unit, 23: used frequency storage unit for each channel

Claims (4)

[Claims] 1. Detecting that communication has started or that the reception signal condition of a frequency channel in use has deteriorated, and scans a number of frequency channels that have been set for empty frequency channels. In a communication device that performs communication using a channel, storage means for storing frequency channel information used by the communication device for communication at least until the next communication of the communication device; and at the time of the next communication, the storage means Control means for reading out the frequency channel information stored in the communication channel and setting the frequency channel of the frequency channel information to be scanned first in the scan of the vacant frequency channel. . 2. Detecting that communication has started or that the reception signal condition of the frequency channel being used has deteriorated,
In a communication device that scans for available frequency channels for a number of frequency channels that have been set and performs communication using the available frequency channels, information on frequency channels used by the communication device for the latest predetermined number of times of communication is obtained. A first storage unit capable of storing; a second storage unit capable of storing usage frequency information of each frequency channel used in the latest predetermined number of communications; and The frequency channel information stored in the first storage means and the use frequency information stored in the second storage means are read, and the scanning order of the frequency channels is set in descending order of the use frequency of the use frequency information. Control means for scanning an available frequency channel. A frequency channel selecting device in a communication device. 3. Detecting that communication has started or that the reception signal condition of the used frequency channel has deteriorated,
A communication device that scans for an available frequency channel for a number of set frequency channels and performs communication using the available frequency channel, wherein the frequency channel information used by the communication device for communication is at least one of the communication devices. A step of storing the frequency channel information stored in the storage means at the time of the next communication, and a step of reading the frequency channel information stored in the storage means at the time of the next communication. Setting a frequency channel to be scanned first. 4. Detecting that communication has started or that the reception signal condition of the frequency channel being used has deteriorated,
In a communication device that scans for available frequency channels for a number of frequency channels that have been set and performs communication using the available frequency channels, information on frequency channels used by the communication device for the latest predetermined number of times of communication is obtained. A step of storing in a storage means, a step of storing in a storage means capable of storing the number of times of use of each frequency channel used in the latest predetermined number of communications, and a step of scanning the free frequency channel, Reading the frequency channel information and the number of times of use information stored in the storage means; and setting a scanning order of the frequency channels of the frequency channel information in order of decreasing frequency of use of the number of times of use and scanning for an empty frequency channel. And a method for selecting a frequency channel in the communication device.