JP2000333259A - Radio communication system and radio terminal station - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce power consumption without reducing the number of available frequency channels by changing part of the prescribed number of frequency channels scanned by one scan operation at every scanning and executing the scan operation. SOLUTION: A plurality of radio terminal stations 20 which are radio- conencted to a radio base station 10 in the radio communication zone of the radio base station 10 are provided. During reception waiting, the number of frequency channels which is scanned by one scan operation is set to be 10 when intermittently scanning individual frequency channels and the number of frequency channels is limited to less than 40 frequency channels that can be received. Five frequency channels which are preferentially selected out of 10 channels are set to be a first frequency channel group A and the other five frequency channels to be a second channel group B. The frequency channels whose use probabilities are high are set to the frequency channels of the group A and the other 35 frequency channels are set to the group B. Then, the scan operation is carried out while every five channels are changed at each period with 35 frequency channels as the group B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication system and a radio terminal station for performing radio communication between a radio base station and a radio terminal station.

[0002]

2. Description of the Related Art Conventionally, in a system for performing wireless communication such as a cordless telephone or a portable telephone, for example, a predetermined number of frequency channels determined by law between a wireless base station and a wireless terminal station are selected. And perform wireless communication. In this case, the wireless terminal station monitors the state of all frequency channels by intermittent channel scanning in order to detect an incoming signal transmitted from the wireless base station by each frequency channel in the reception standby state. When an incoming signal to the own station is detected, a wireless line is connected using the frequency channel to perform communication.

[0003]

However, in the above-mentioned prior art, the radio terminal station performs a scan operation of all the frequency channels that can communicate in the reception standby state. The channel scan operation time becomes longer. Therefore, although the power consumption is reduced by the intermittent operation, 1
There is a problem that the time of one channel scan operation becomes longer than the pause time between each channel scan operation, and the power saving effect is reduced. On the other hand, when the number of frequency channels for performing the channel scan is reduced, the effect of saving power consumption is increased, but the number of available channels is reduced, and there is a problem that the number of cases where line connection cannot be performed increases.

An object of the present invention is to provide a radio communication system and a radio terminal station that can reduce the power consumption of the intermittent reception operation by channel scanning without reducing the number of available frequency channels.

[0005]

In order to achieve the above object, the present invention has a plurality of frequency channels for performing wireless communication between a wireless base station and a wireless terminal station, wherein the wireless terminal station comprises:
In a wireless communication system that intermittently scans a plurality of frequency channels and detects an incoming call in a reception standby state, the wireless terminal station performs one scan operation when intermittently scanning the plurality of frequency channels. The number of frequency channels to be scanned in is limited to the number of frequency channels smaller than the frequency channels that the wireless terminal station can receive, and a part of a predetermined number of frequency channels to be scanned in one scan operation is set for each scan. It is characterized in that the scan operation is performed with the change.

The present invention also provides a wireless terminal station having a plurality of frequency channels for performing wireless communication with a wireless base station, and intermittently scanning the plurality of frequency channels in a reception standby state to detect an incoming call. In the case of intermittently scanning the plurality of frequency channels, while limiting the number of frequency channels to scan in one scan operation to the number of frequency channels less than the frequency channels that the wireless terminal station can receive, The scanning operation is performed by changing a part of a predetermined number of frequency channels to be scanned in one scanning operation for each scanning.

In the wireless communication system and the wireless terminal station according to the present invention, when the wireless terminal station intermittently scans a channel, the number of frequency channels to be scanned in one scanning operation is determined by the frequency that the wireless terminal station can receive. By limiting the number of frequency channels to be smaller than the number of channels, it is possible to reduce the time required for one scan operation and to reduce power consumption. Further, the scan interval can be shortened, and a quick connection operation can be realized. Further, by changing a part of a predetermined number of frequency channels to be scanned in one scan operation for each scan and performing the scan operation, all available frequency channels can be scanned by a plurality of scans. . Therefore, the power consumption of the intermittent reception operation by the channel scan can be reduced without reducing the number of available frequency channels.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a radio communication system and a radio terminal according to the present invention will be described. FIG. 1 is a block diagram showing a configuration of a wireless communication system according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a configuration of a wireless terminal station in the wireless communication system shown in FIG.

As shown in FIG. 1, the radio communication system includes a radio base station 10 connected to a wired line 30 from a public line network or the like, and a radio base station 10 in a radio communication zone of the radio base station 10. Wireless terminal stations 2 wirelessly connected to
0. Also, as shown in FIG.
0 is a control unit 210 that controls the entire radio base station 20.
An antenna 220 for transmitting and receiving a radio wave, a radio communication unit 230 for performing radio communication with the radio base station 10, a voice processing unit 240 for processing a voice signal, and a microphone 250 for transmitting voice. And a speaker 260 for receiving a call.
, An LCD display unit 270 for performing various displays, a key input unit 280 for performing various key inputs, and a memory unit 290 for storing various data.

FIG. 3 is a flowchart showing the operation of the wireless terminal station 20 of the present embodiment during reception and reception standby.
FIG. 4 is an explanatory diagram illustrating an example of a channel group scanned by the intermittent reception operation in the wireless terminal station 20 of the present example. In this example, the number of frequency channels available for wireless communication is set to 40, and the number of frequency channels to be scanned by the intermittent operation during reception standby is set to 10 channels. That is, in the wireless communication system of this example,
When intermittently scanning each frequency channel during reception standby, the number of frequency channels to be scanned in one scan operation is set to 10, and by limiting the number of frequency channels to less than 40 receivable frequency channels. It is intended to reduce the time required for one scan operation and to reduce power consumption.

In the radio communication system of the present embodiment, five frequency channels to be preferentially selected from the ten channels to be scanned are defined as a first frequency channel group (Group A), and the other five frequency channels are selected. Channels are assigned to a second frequency channel group (Group
B). Then, a frequency operation having a high use probability is set to the five frequency channels of Group A, and the scanning operation is performed while changing the other 35 frequency channels as Group B by five every frequency in one cycle. Scanning of all available 40 frequency channels is performed by scanning a plurality of times while securing quick connection with frequency channels having a high use probability, thereby enabling use of all frequency channels. Also, by reducing the number of channels to scan,
It is possible to shorten the interval at which the intermittent operation of the scanning operation is performed, and particularly to a frequency channel of Group A having a high use probability, it is possible to quickly connect.

In this embodiment, five frequency channels are selected as frequencies having a high use probability, starting from the frequency channel used for the previous connection. For example, when all 40 available frequency channels are described with channel numbers 1 to 40, as shown in FIG. 4, when the frequency channel used for the previous connection is channel number 1, With this channel number 1 as a starting point, every other five frequency channels are selected. That is, in this case, channel numbers 1, 3, 5, 7, and 9 are selected and Gr
Set to upA.

The Group B is changed every scan. In this case, in the first scan from the end of the communication, the channel numbers 2, 4, 6, 8, and 10 are selected and set as the Group B. In the next scan, channel numbers 11, 12, 13, 14, and 15 are selected and set to Group B. Further, in the next scan, channel numbers 16, 17, 18, 19, and 20 are selected and set to Group B. In this manner, all the 40 channels are scanned by the seven scanning operations.

On the other hand, in the radio base station 10, Group A is calculated for each radio terminal station 20 in the same manner, and when a call arrives at the corresponding radio terminal station 20, the frequency of Group A in the radio terminal station 20 is calculated. An incoming signal is transmitted using a channel. Where G
When the frequency channel of the loop A is in a strong electric field state (busy), an incoming signal is transmitted using another arbitrary frequency channel. In this way, Gro
The incoming operation can be quickly performed using the upA frequency channel, and if the Group A frequency channel is being used for another communication, the incoming operation can be performed using the Group B frequency channel.

The method of determining Group A is as follows.
Databases storing channel maps and the like that can determine the usage status of all channels based on past communication histories and the like can be installed in the radio base station 10 and the radio terminal station 20, respectively, and can be determined based on the databases. It is. The example shown in FIG. 4 is an example of a case where such a database is not used and a decision is made using a simple rule. In any case, the frequency channel used at the time of the immediately preceding connection is included in Group A. Also,
GroupA may include not only the frequency channel used immediately before, but also a plurality of frequency channels used in the latest several connections. Also, such Grou
When the incoming call is actually detected by the channel scan and the line is connected, the pA is changed starting from the connected frequency channel.

Hereinafter, an example of the overall operation will be described with reference to the flowchart of FIG. First, in step S1, a wireless communication operation based on reception is being performed, and when this end is detected (step S2), the first frequency channel group (Group A) based on the frequency channel used at the time of connection in step S1. Is selected (step S3). Further, a second frequency channel group (Group B) is selected from other frequency channels.
Then, a channel scan operation is performed using these selected Group A and B frequency channels (Step S5). If an incoming call is detected by this channel scanning operation (step S6), the process proceeds to step S1, where a line connection is made, and a transition is made to communication.

If no incoming call is detected in step S6, the second frequency channel group (Group B) is updated from the remaining frequency channels (step S6).
7) If the sleep time of the intermittent operation has elapsed, the process proceeds to step S5 to execute the channel scan operation.
As described above, while changing Group A for each line connection and changing Group B for each scan operation, the channel scan operation is performed with a small number of scan channels, and the intermittent reception operation is performed.

Although an example in which the present invention is applied to a portable telephone system has been described above, the present invention is not limited to this. For example, a cordless telephone system for home use or a wireless communication system other than telephones may be used. It can be widely applied as various wireless communication systems and wireless terminal stations.

[0019]

As described above, in the wireless communication system of the present invention, when the wireless terminal station intermittently scans a plurality of frequency channels, the number of frequency channels to be scanned in one scanning operation is determined by the number of the wireless channels. The number of frequency channels is smaller than the number of frequency channels receivable by the terminal station, and a scan operation is performed by changing a part of a predetermined number of frequency channels to be scanned by one scan operation for each scan. . Therefore, it is possible to provide a wireless communication system capable of reducing the power consumption of the intermittent reception operation by the channel scan without reducing the number of available frequency channels.

Further, in the wireless terminal station of the present invention, when intermittently scanning a plurality of frequency channels, the number of frequency channels to be scanned in one scanning operation is set to be smaller than the number of frequency channels that the wireless terminal station can receive. The number of frequency channels is limited to a small number, and a part of a predetermined number of frequency channels to be scanned in one scan operation is changed for each scan to perform the scan operation. Therefore, there is an effect that it is possible to provide a wireless terminal station that can reduce the power consumption of the intermittent reception operation by the channel scan without reducing the number of available frequency channels.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a wireless communication system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a wireless terminal station in the wireless communication system shown in FIG.

FIG. 3 is a flowchart showing an operation during reception and reception standby in a wireless terminal station of the wireless communication system shown in FIG. 1;

FIG. 4 is an explanatory diagram showing an example of a channel group scanned by an intermittent reception operation in a wireless terminal station of the wireless communication system shown in FIG. 1;

[Explanation of symbols]

10 radio base station, 20 radio terminal station, 30 line, 210 control unit, 220 antenna, 230
... Wireless communication unit, 240 ... Sound processing unit, 250 ... Microphone, 260 ... Speaker, 270 ... LCD display unit, 2
80 ... key input section, 290 ... memory section.

Claims (9)

[Claims] The wireless terminal station has a plurality of frequency channels for performing wireless communication between a wireless base station and a wireless terminal station, and the wireless terminal station intermittently scans the plurality of frequency channels in a reception standby state to receive a call. In the wireless communication system performing the detection of, when the wireless terminal station intermittently scans the plurality of frequency channels, the wireless terminal station can receive the number of frequency channels to be scanned in one scan operation The number of frequency channels is smaller than the number of frequency channels, and a scan operation is performed by changing a part of a predetermined number of frequency channels to be scanned in one scan operation for each scan. Wireless communication system. 2. The wireless communication system according to claim 1, wherein said wireless terminal station preferentially selects a frequency channel having a high use probability and performs a scanning operation. 3. The wireless terminal station creates a first group in which a predetermined number of frequency channels are selected based on a frequency channel to which a wireless line was previously connected, and a predetermined number of frequency channels other than the first group. A second group of selected channels is created, a scan is performed using the first group and the second group of frequency channels, and the frequency group of the second group is changed for each scan. The wireless communication system according to claim 2, wherein scanning is performed. 4. The wireless communication system according to claim 3, wherein when the wireless terminal station is connected to a wireless channel, the wireless terminal station changes the first group based on the connected frequency channel. 5. The radio base station according to claim 1, wherein when the radio terminal station receives a call in a reception standby state, the radio base station preferentially selects a frequency channel of the first group and transmits a call signal. 3. The wireless communication system according to 3. 6. A wireless terminal station having a plurality of frequency channels for performing wireless communication with a wireless base station and intermittently scanning a plurality of frequency channels in a reception standby state to detect an incoming call. When intermittently scanning a plurality of frequency channels, the number of frequency channels to be scanned in one scanning operation is limited to a smaller number of frequency channels than the frequency channels that can be received by the wireless terminal station. A wireless terminal station, wherein a scan operation is performed by changing a part of a predetermined number of frequency channels to be scanned in a scan operation for each scan. 7. The radio terminal according to claim 6, wherein a scanning operation is performed by preferentially selecting a frequency channel having a high use probability. 8. A first group in which a predetermined number of frequency channels are selected based on a frequency channel to which a wireless line is connected last time, and a second group in which a predetermined number of frequency channels other than the first group are selected. And a scan is performed using the frequency channels of the first group and the second group, and the frequency channels of the second group are changed for each scan to perform the scan. 8. The method according to claim 7, wherein
The wireless terminal station as described. 9. The wireless terminal station according to claim 7, wherein when a wireless line is connected, the first group is changed based on the connected frequency channel.