JP2000092571A - Radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a radio communication system capable of starting radio communication by quickly setting up a talking channel at the time of establishing radio connection between a master station and a slave station by multi-channel access. SOLUTION: A master station 1 executes dead channel judging from timing t0. Out of slave stations 2, 3 in intermittent receiving, the slave station 2 turns on reception at first and transmits reception ON informing data to the master station 1 at timing t1. The master station 1 transmits dead channel informing data to the slave station 1 at timing t2 in order to inform the slave station 1 of a judged dead channel and the slave station 2 executes dead channel judging of the corresponding talking channel at timing t3, and at the time of judging the talking channel as a dead channel, transmits dead channel check data to the master station 1 at timing t4. Then the slave station 3 executes similar processing. Since both of the master station 1 and the slave stations 2, 3 can recognize that a talking channel is a dead channel in common, time required for establishing radio communication thereafter can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, an analog cordless telephone system, in which a multi-channel access technique is used to transmit and receive control data between a master station and one or more slave stations via a control channel, thereby enabling a plurality of calls. It belongs to the technical field of a wireless communication system that performs wireless communication by allocating one communication channel from channels.

[0002]

2. Description of the Related Art In recent years, in an analog cordless telephone system which has become widespread, a vacant channel is determined from a large number of communication channels by using a multi-channel access technology, and an unused communication channel is selected and used as a parent. A wireless connection is established between the station and the slave station, and wireless communication is performed.
In this communication channel, an FM-modulated voice signal is transmitted and received, and various data such as MSK-modulated dial information are transmitted and received.

On the other hand, since the master station and the slave station have different reception frequency bands, it is necessary to perform the above-described determination of an empty channel before establishing a wireless connection in both the master station and the slave station. That is, if the master station determines that a predetermined communication channel in the 250 MHz band to be received by the master station is an idle channel, the master station designates this idle channel as a slave station, and the slave station responds to the 380 MHz band to be received. After confirming whether or not the communication channel to be used is a free channel, wireless connection is finally performed using this communication channel. At this time, if the master station searches for a plurality of free channels in advance and holds it as a candidate for a free channel to be designated as a slave station, the determination of a free channel at the time of wireless connection is performed many times. The wireless connection can be efficiently performed without having to perform the connection.

[0004]

However, when establishing a wireless connection as described above, transmission and reception between a master station and a slave station are performed using a control channel, whereas determination of an idle channel involves switching a reception frequency to a communication channel. Need to be done. It takes about several tens of milliseconds to stabilize the reception frequency in the radio circuit, and if the control channel and the communication channel are shifted many times in both the master station and the slave station, the total time is considerably long. That would be.

In addition, considering that the reception frequency band and the installation position of the master station and the slave station are different, the communication channel determined to be an idle channel by the master station is also determined to be an idle channel by the slave station. Not necessarily. As a result, a longer time may be required until both the master station and the slave station find a communication channel determined to be an idle channel.

As described above, the conventional cordless telephone has a problem that it is difficult to establish a wireless connection between a master station and a slave station within a short time. The present invention
In view of such a problem, when establishing a wireless connection between a master station and a slave station, a wireless communication that can shift to an available channel and start wireless communication in a short time. It is an object to provide a communication system.

[0007]

According to a first aspect of the present invention, there is provided a wireless communication system including a master station and one or more slave stations, wherein the master station and the slave station are predetermined. According to the control data transmitted and received by the control channel
A wireless communication system that performs wireless communication using one communication channel set from a plurality of communication channels,
The master station is a vacant channel detecting means for detecting a vacant channel from the plurality of communication channels, and vacant channel notification data indicating a vacant channel based on a detection result of the vacant channel detecting means to a receivable slave station. And the idle channel notification data transmitting means for transmitting the idle channel notification data by the control channel, and when the slave station receives the idle channel notification data from the master station, the communication channel corresponding to the idle channel notification data is an idle channel. An empty channel confirmation data transmitting unit for transmitting, by the control channel, empty channel confirmation data indicating a confirmation result of the empty channel confirmation unit to the master station; The idle channel notification data and the idle channel confirmation data between the master station and the slave station Transmission and reception, characterized in that it is performed repeatedly at a predetermined timing.

According to the present invention, the master station detects a vacant channel from a plurality of communication channels at appropriate times, and transmits the vacant channel notification data to the receivable slave station on the control channel based on the detection result. I do. The slave station receiving this confirms whether the corresponding communication channel is a free channel and transmits free channel confirmation data indicating the result of the confirmation to the master station via the control channel. These transmission / reception processes are repeatedly performed at an appropriate timing while the slave station is waiting. So, at a particular point in time,
The communication channel determined to be an idle channel by both the master station and the slave station can be commonly recognized by the master station and the slave station. Wireless communication can be started.

A wireless communication system according to a second aspect of the present invention is the wireless communication system according to the first aspect, wherein the idle channel notification data between the master station and the slave station only when the slave station is charging. And transmitting and receiving the empty channel confirmation data.

According to the present invention, transmission and reception for notifying and confirming an empty channel as described above is not performed between a slave station that is not charging and the master station, and the transmission and reception is performed only for the slave station that is charging. To do. Therefore, the wireless connection between the master station and the slave station can be established in a short time if at least one slave station is being charged without increasing the power consumption of the slave station.

According to a third aspect of the present invention, in the wireless communication system according to the first or second aspect, the slave station can receive the idle channel notification data from the master station. Further comprising reception state notification data transmitting means for repeatedly transmitting the reception state notification data at predetermined timing by a control channel, wherein the master station, when receiving the reception state notification data from the slave station, the idle channel The notification data is transmitted by the idle channel notification data transmitting means.

According to the present invention, the slave station repeatedly transmits the reception state notification data to the master station at a predetermined timing on the control channel, and notifies the master station that the available channel data can be received. After the master station receives the request, the above-described transmission / reception for notifying and confirming the empty channel is performed. Therefore, when appropriate conditions for recognizing an empty channel, such as a state of charge and a state of intermittent reception, are satisfied, necessary information on an empty channel can be acquired.

According to a fourth aspect of the present invention, in the wireless communication system according to the third aspect, the slave station performs an intermittent reception operation on the control channel at a preset time interval during standby. In addition, when a transition is made from the reception stop state to the reception operation state during the intermittent reception operation, the reception state notification data is transmitted by the reception state notification data transmitting means.

According to the present invention, the slave station performs intermittent reception on the control channel at a preset time interval during standby, and transmits reception state notification data to the master station at a timing when the reception state switches from off to on. I did it.
Therefore, the slave station can reliably acquire the information on the necessary free channel while updating the information at each intermittent reception cycle.

According to a fifth aspect of the present invention, in the wireless communication system according to the fourth aspect, the slave station performs an intermittent reception operation when the mobile station is not charging and waits while the mobile station is waiting. Is characterized in that the receiving operation is continuously performed without performing the intermittent receiving operation.

According to the present invention, the slave station does not perform the intermittent reception operation when not charging, but performs the intermittent reception operation only when charging to perform the above-described transmission and reception. Therefore, it is possible to acquire the information on the necessary free channel at the optimal timing suitable for the case where the slave station is charging and the case where the slave station is not charging.

According to a sixth aspect of the present invention, in the wireless communication system according to the fourth or fifth aspect, the slave station shifts from a reception stop state to a reception operation state during an intermittent reception operation. And a reception timing setting means for randomly setting each of the slave stations.

According to the present invention, at the time of the intermittent reception operation, the slave station performs the above-mentioned transmission and reception after randomly setting the timing at which the reception state switches from off to on for each slave station. Therefore, when reception is turned on at the same timing at different slave stations, even if the transmission of the reception state notification data collides, it is possible to avoid a situation where the transmission repeatedly collides thereafter.

According to a seventh aspect of the present invention, in the wireless communication system according to any one of the first to sixth aspects, the master station establishes a wireless connection with the slave station. An idle channel designation data transmitting unit for transmitting idle channel designation data for designating an empty channel based on a detection result of the empty channel detection unit as a communication channel to be connected to the slave station by the control channel, The slave station, when receiving the empty channel designation data from the master station, if the communication channel corresponding to the empty channel designation data has already been confirmed to be an empty channel by the empty channel confirmation means, Free channel confirmation data indicating the confirmation result is transmitted to the master station by the free channel confirmation data transmitting means, Wherein the wireless connection using the call channel between the serial master station is established.

According to the present invention, when establishing a wireless connection between the master station and the slave station, the master station transmits the idle channel designation data to the slave station through the control channel based on the detection result of the idle channel. The slave station that has received, when it has been confirmed in advance that the corresponding communication channel is a free channel, transmits free channel confirmation data to the master station without checking the free channel again, A wireless connection using this communication channel is established between the master station and the slave stations. Therefore, when establishing a wireless connection, it is not necessary for both the master station and the slave station to judge an empty channel, and the results of the processing performed in advance between the master station and the slave station can be effectively used to quickly The operation can be shifted to the call operation.

According to an eighth aspect of the present invention, in the wireless communication system according to any one of the first to seventh aspects, the wireless communication system is a cordless telephone system connected to a telephone line. It is characterized by.

According to the present invention, in the cordless telephone system, the above-described processing is performed between the master station and the slave station, for example, when receiving an incoming call on a telephone line. Therefore,
In a cordless telephone system, a wireless connection can be quickly established while accurately determining an available channel.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. Here, a master station and a plurality of slave stations are provided, and a wireless connection is established between the master station and the slave stations by a multi-channel access method using a 250 MHz band / 380 MHz band to transmit and receive voice signals and various data. An embodiment in which the present invention is applied to an analog cordless telephone system to be performed will be described.

FIG. 1 is a block diagram showing a system configuration of the cordless telephone system according to the present embodiment. FIG.
As shown in FIG. 1, the cordless telephone system according to the present embodiment includes a master station 1 connected to a telephone line, and slave stations 2 and 3 wirelessly connected to the master station 1. Note that the number of slave stations may be larger, but for simplicity, two
A case where only a slave station is included will be described.

In FIG. 1, the transmission frequency of the master station 1 and the reception frequency of the slave stations 2 and 3 are in the 380 MHz band when the wireless connection is established between the master station 1 and the slave stations 2 and 3. And the reception frequency of the master station 1 are in the 250 MHz band. And in each frequency band,
A total of 89 wireless channels are reserved. Most of the radio channels are allocated as speech channels, but some predetermined radio channels are used as control channels. The master station 1 and the slave stations 2 and 3 first establish a wireless connection using the control channel, and perform wireless communication thereafter using one communication channel confirmed to be an empty channel.

Before starting wireless communication by the communication channel between the master station 1 and the slave stations 2 and 3, various control data are transmitted and received by the half-duplex method using the control channel. Then, MSK modulation is performed on the control channel based on the control data, and transmission is performed from the master station 1 to the slave stations 2 and 3 or from the slave stations 2 and 3 to the master station 1. The control data to be transmitted and received includes various types of information related to a free channel for the communication channel, which will be described in detail later.

On the other hand, it is assumed that a wireless connection has been established and, for example, the child stations 2 and 3 have started a telephone call via the master station 1. At this time, a predetermined communication channel in the 250 MHz band is FM-modulated and transmitted to the master station 1 by an audio input signal from the slave stations 2 and 3 such as microphones.
This is demodulated and transmitted to the telephone line. On the other hand, a predetermined communication channel in the 380 MHz band is FM-modulated and transmitted to the slave stations 2 and 3 by a voice signal arriving at the master station 1 from the telephone line. Output audio from a receiver or the like. As described above, between the master station 1 and the slave stations 2 and 3, an audio signal is transmitted / received in full-duplex using two frequencies.

FIG. 2 is a timing chart in the case of transmitting and receiving various kinds of free channel information for notifying each other of the status of free channels between the master station 1 and the slave stations 2 and 3. In the present specification, a hatched portion in the timing chart indicates a shift to a communication channel. The example of FIG. 2 shows an operation in the case where the slave stations 2 and 3 are performing intermittent reception during standby and transmitting and receiving free channel information to and from the master station 1.

Prior to transmitting free channel notification data to the slave stations 2 and 3, the master station 1 performs an idle channel determination process for a predetermined communication channel. for that reason,
At timing t0 shown in FIG. 2, the transition to the receiving operation for the communication channel to be checked is started. Before and after the actual idle channel determination processing, a certain time is required to stabilize the reception frequency by switching between the control channel and the communication channel as shown by hatching in the figure. Specifically, the empty channel determination process may determine that the channel is an empty channel when the reception level is equal to or lower than a predetermined set value, and determine that the channel is busy when the reception level exceeds this value. Here, the following description will be made on the assumption that the communication channel is determined to be an empty channel.

On the other hand, the slave stations 2 and 3 perform an intermittent reception operation for the control channel. That is, the control channel is changed from the reception off state to the reception on state at regular time intervals, and the control channel is received. That is, power supply to the wireless system is started, the reception frequency is stabilized to the frequency of the control channel, and the processing described later is performed. Usually, the time interval of the intermittent reception is appropriately set based on the power consumption of the slave stations 2 and 3 and the limitation of the response time. Note that the slave stations 2 and 3 of the present embodiment
Performs not only reception of a control channel but also transmission of predetermined control data. Therefore, when control data is transmitted when reception is on, it is necessary to perform transmission operations simultaneously.

After the reception is turned on, the slave station 2 transmits reception-on notification data as reception state notification data to the master station 1 at timing t1. This is control data transmitted to notify the master station 1 that the slave station 2 can receive the idle channel notification data.

When the master station 1 receives the reception ON notification data from the slave station 2, it can determine that the determined vacant channel can be used as a communication channel with the slave station 2, so that the vacant channel is immediately used at timing t2. The channel notification data is transmitted to the slave station 2 through the control channel. This is control data transmitted to notify the slave station 2 of an available channel that can be used as a communication channel.

Subsequently, when the slave station 2 receives the idle channel notification data from the master station 1, after the timing t3, the slave station 2 determines whether or not the communication channel indicated by the idle channel notification data is also an idle channel in the slave station 2. judge. That is, this communication channel is the reception frequency band 2 of the master station 1.
In the 50 MHz band, although it is determined by the master station 1 as an empty channel, the 380 MHz band which is the reception frequency band of the slave station 2 is not necessarily an empty channel, so the slave station 2 checks the channel. . In this case as well, a certain amount of time is required before and after the idle channel determination processing to stabilize the reception frequency by switching between the control channel and the communication channel as indicated by the hatched lines in the figure.

As a result, at a timing t4 after it is determined that the communication channel is an idle channel, the idle channel confirmation data is transmitted to the master station 1 through the control channel. This is control data transmitted to inform the master station 1 that the communication channel notified as a free channel from the master station 1 is also confirmed to be a free channel in the slave station 2 as well. If the slave station 2 does not determine that the communication channel is a free channel, the free channel busy notification data indicating that the communication channel is busy (in use) is used instead of the free channel confirmation data. Just send it.

On the other hand, after the slave station 3 is turned on later than the slave station 2, the slave station 3 transmits reception-on notification data to the master station 1 through the control channel at timing t5, similarly to the slave station 2. Thereafter, the transmission of the idle channel notification data from the master station 1 to the slave station 3, the confirmation of the idle channel performed by the slave station 3, and the transmission of the idle channel confirmation data from the slave station 3 to the master station 1 are performed as described above. Since the operation is performed in the same manner as in the case of the station 2, the description is omitted.

As described above, the communication channels that have been made idle by the parent station 1 and the child station 2 and the communication channels that have been made idle by the parent station 1 and the child station 3 are different from each other. The stations 2 and 3 may be stored in the memory means. Thereby, thereafter, the master station 1 and the slave station 2 or the slave station 3
Can be effectively used as free channel information when establishing a wireless connection.

In FIG. 2, the case where each of the slave stations 2 and 3 performs the intermittent reception operation at a fixed time interval has been described. However, this time interval may be set randomly for each slave station. That is, when the slave stations 2 and 3 shift from the reception-off state to the reception-on state at substantially the same time, the transmission of the reception-on notification data may collide with each other. At this time, if the time interval of the intermittent reception is randomly set each time, the probability that the reception-on notification data will continuously collide becomes extremely low, and the reception-on notification data is transmitted to the master station 1 immediately. be able to.

Therefore, the slave stations 2 and 3 may be provided with, for example, random number generating means to calculate a time interval of intermittent reception every time and perform timing control. Since it is not preferable that the time interval fluctuates extremely, the above-described effect can be obtained even if a certain range of fluctuation is provided before and after a certain time interval.

FIG. 2 illustrates the case where the slave stations 2 and 3 transmit the reception-on notification data to the master station 1 after the reception is turned on in the intermittent reception. The master station 1 may repeatedly transmit the idle channel notification data to the slave stations 2 and 3 without transmitting the reception-on notification data. In this case, when the slave stations 2 and 3 receive the idle channel notification data at the timing when the reception is turned on, the idle channel confirmation data is transmitted to the master station 1.

It is desirable that the processing of the slave stations 2 and 3 described with reference to FIG. 2 is set to be performed only by the slave station being charged. That is, in the above-described processing, the transmission power needs to be turned on for a certain period of time in order to transmit predetermined control data in a state where reception is on during intermittent reception. growing. Therefore, the slave stations 2, 3
In order to avoid a reduction in the standby time due to an increase in power consumption in the above, only the charging slave station placed on a charging stand or the like performs the above-described processing, and a non-charging slave station performs the above-described processing. It is desirable not to do it. Even in this case, if at least one slave station is charging, the above processing can be performed.
The effects of the present invention can be obtained. If it is not necessary to increase the standby time due to the usage status of the slave stations 2 and 3, the non-charging slave station may perform the above processing.

Further, when the slave station being charged performs the above-described processing, the above-described intermittent reception control may not be performed during charging, and may be switched to a continuous reception operation. Thereby, the timing at which the slave station transmits the reception-on notification data can be determined without being restricted by the time interval of the intermittent reception, so that the free channel information with a high degree of freedom can be transmitted and received.

Next, FIG. 3 is a timing chart until a wireless connection is established between the master station 1 and the slave stations 2 and 3 when the master station 1 receives an external call from a telephone line. . FIG.
In the example, it is also assumed that the slave stations 2 and 3 are performing intermittent reception while waiting, and an external line call is received by the master station 1.

When receiving an external line call coming from the telephone line at timing t10, master station 1 performs the above-described vacant channel determination processing for a predetermined communication channel. Next, the vacant channel specifying data specifying the vacant channel determined at the timing t11 is transmitted to the slave station 2 through the control channel. This is control data transmitted to inform the slave station 2 of an available channel that can be used as a communication channel to be connected as a communication channel.

At this time, as shown in FIG.
At 11, the slave station 2 is off during intermittent reception. Therefore, the slave station 2 cannot receive the idle channel designation data from the master station 1.

Since the free channel confirmation data is not transmitted from the slave station 2 at the master station 1, the master station 1 continues at timing t12.
The vacant channel designation data is transmitted to the slave station 3 through the control channel. Since the slave station 3 is turned on at the timing t12 as shown in FIG. 3, the slave station 3 can receive the empty channel designation data.

Since the slave station 3 has already confirmed that the communication channel indicated by the vacant channel designation data is a vacant channel by the processing shown in FIG. Immediately transmits the empty channel confirmation data to the master station 1 via the control channel. Thereafter, the slave station 3 shifts to the designated communication channel, and enters a reception standby state.

Subsequently, at the timing t14, the master station 1 transmits the empty channel designation data to the slave station 2 again by the control channel. At this time, the slave station 2 is in the reception-on state at the timing t14 as shown in FIG. 3, and thus can receive the empty channel designation data. Then, like the slave station 3, the slave station 2 has already confirmed that the corresponding communication channel is an empty channel.
At timing t15, the vacant channel confirmation data is immediately transmitted to the master station 1 via the control channel. Thereafter, the master station 1 and the slave station 2 shift to the designated communication channel.

The master station 1 transmits a bell ringing command to the slave stations 2 and 3 through the communication channel at timing t16. The slave stations 2 and 3 receive the bell ringing command,
Actually ring the bell and wait for the user to go off-hook. Thereafter, when the slave station 2 or the slave station 3 goes off-hook, communication with the other party on the telephone line is started.

Next, the processing performed by the master station 1 in the present embodiment will be described with reference to the flowcharts of FIGS. In FIGS. 4 to 6, the processing performed from the state in which the master station 1 is not wirelessly connected to the slave stations 2 and 3 until the wireless connection is finally established and the communication between the slave stations 2 and 3 starts is described. It will be described sequentially.

In FIG. 4, the master station 1 starts a receiving operation for the control channel (step S1), and determines whether or not the calling data from the slave stations 2 and 3 has been received by the control channel (step S2). If the decision result in the step S2 is "YES", the process moves to a step S17.

On the other hand, the judgment result of step S2 is "NO"
If it is, then it is determined whether or not there is an incoming call from the telephone line (step S3). Then, if the decision result in the step S3 is "YES", the process moves to a step S25. If "NO", a free channel decision is made.
The reception frequency is switched to shift to a predetermined communication channel (step S4).

Next, the above-described vacant channel determination processing is performed for this communication channel to determine whether or not the channel is a vacant channel (step S5). If the decision result in the step S5 is "NO", this communication channel is busy and cannot be used for wireless connection with the slave stations 2 and 3, so that the reception frequency is further switched to shift to another communication channel. (Step S6). Again, the vacant channel determination process is similarly performed on the transfer channel after the transfer to determine whether or not the channel is a vacant channel (step S7). If the decision result in the step S7 is "NO", a step S7 is executed.
6 and step S7 are repeated to continue searching for a free communication channel while switching the communication channel.

When the determination result of step S5 or step S7 is "YES" and an empty channel is found, the receiving frequency is switched to shift to the control channel (step S8). Then, in order to receive various control data transmitted from the slave stations 2 and 3, the reception standby state for the control channel is maintained (step S9), and whether or not the above-described reception-on notification data is received from the slave stations 2 and 3 Is determined (step S10). The determination result of step S10 is "NO"
If, the steps S9 and S10 are repeated to wait for reception of the reception-on notification data.

Then, the reception ON notification data from the slave stations 2 and 3 is received, and the result of the determination in step S10 is "YE
S, the free channel notification data using the free channel determined in step S5 or S7 as data is transmitted to the slave station 2 or the slave station 3 (step S1).
1). Subsequently, it is determined whether or not the above-mentioned empty channel confirmation data has been received from the slave station 2 or the slave station 3 (step S12).

If the decision result in the step S12 is "NO", it means that the corresponding communication channel has not been confirmed as a free channel in the slave station 2 or the slave station 3.
Further, the reception frequency is switched to another communication channel (step S13), and similarly, an empty channel determination process is performed to determine whether the channel is an empty channel (step S13).
14). If the decision result in the step S14 is "NO", the steps S13 and S14 are repeated, and the search for a free channel is continued while switching the channel. If the determination result of step S14 is "Y
If it is "ES", the process returns to step S11, where
Alternatively, it transmits to the slave station 3 free channel notification data using the newly determined free channel as data.

On the other hand, if the result of the determination in step S12 is "YE
If "S", it is determined whether or not the transmission of the free channel notification data to all the slave stations 2 and 3 has been completed (step S15). If the result of the determination in step S15 is "NO", it is determined whether or not a predetermined time has elapsed (step S16). If the decision result in the step S16 is "NO", the process in and after the step S9 is repeated, and if "YES", a timeout occurs and the process ends. Also, when the result of the determination in step S15 is "YES", it means that the free channel notification data has been transmitted to all the slave stations 2 and 3, so that step S9.
The subsequent processing is repeated. The processing shown in FIG.
Is repeated as appropriate.

Next, with reference to FIG. 5, a description will be given of the processing in the case where the process proceeds from step S2 to step S17. Here, the description will be made on the assumption that the master station 1 has received the call data from the slave station 2.

First, the master station 1 shifts to one communication channel for wireless communication in order to correspond to the call data from the slave station 2 (step S17). The above-described free channel determination processing is performed on this communication channel to determine whether or not the channel is a free channel (step S18). If the decision result in the step S18 is "NO", the process shifts to another communication channel (step S19), and similarly, performs an empty channel determination process (step S20), and continues to search for an empty channel.

If the result of the determination in step S18 or S20 is "YES" and a free channel is found, the control is shifted to the control channel (step S21), and a free channel designating this free channel is given to the slave station 2. The designated data is transmitted (step S22). Thereafter, the communication channel shifts to the corresponding communication channel (step S23), and when the slave station 2 similarly shifts to the communication channel, a predetermined communication process is started (step S24).

Next, with reference to FIG. 6, a description will be given of a process in the case where the process proceeds from step S3 to step S25. Here, a process in the case where the master station 1 specifies the communication channel in the order of the slave station 2 and the slave station 3 will be described.

First, the master station 1 shifts to one communication channel for performing wireless communication with the slave stations 2 and 3 in order to perform processing corresponding to an incoming call from an outside line (step S25). The above-described free channel determination processing is similarly performed on this communication channel to determine whether or not the channel is a free channel (step S26). If the decision result in the step S26 is "NO", the process shifts to another communication channel (step S2).
7) Similarly, an empty channel determination process is performed (step S28), and the search for an empty channel is continued.

If the result of the determination in step S26 or S28 is "YES" and an empty channel is found, the operation shifts to the control channel (step S29). The designated data is transmitted (step S30). Then, it is determined whether or not the free channel confirmation data for the free channel designation data has been received for all the slave stations 2 and 3 (step S31). At this stage, since the idle channel designation data has not been transmitted to the slave station 3, even if the idle channel confirmation data is immediately received from the slave station 2, “NO” is determined in the step S 31.

Subsequently, it is determined whether or not a predetermined time has elapsed from the start of the process and a timeout has occurred (step S3).
2). If the decision result in the step S32 is "NO",
Returning to step S30, the same processing is continued for the next slave station 3. For example, when the slave station 2 or the slave station 3 has run out of battery or is placed outside the radio coverage area, the time-out occurs without receiving the idle channel confirmation data. The predetermined time until the timeout is determined in consideration of the time interval of the intermittent reception of the slave stations 2 and 3, and is usually set to about 2 or 3 seconds.

If the result of the determination in step S31 or S32 is "YES", the process shifts to the corresponding communication channel (step S33). Communication processing is started (step S34).

Next, the processing performed by the slave station 2 in the present embodiment will be described with reference to the flowcharts of FIGS. In FIG. 7 to FIG. 9, from the state where the slave station 2 is performing the intermittent reception operation, a wireless connection is finally established to
The processing performed until the start of the telephone conversation with will be described sequentially. In addition, since the same processing is performed in the case of the slave station 3,
The case of the slave station 2 will be described as a representative.

In FIG. 7, the slave station 2 performs an intermittent reception operation, and at a predetermined timing, shifts from the reception off state to the reception on state (step S41), and starts the reception operation for the control channel (step S41). S42). Then, it is determined whether or not the call data from the master station 1 has been received (step S43), and if the determination result is “YES”, the process proceeds to step S56.

On the other hand, if the result of the determination in step S43 is "N
If "O", then it is determined whether or not the call data is transmitted to the master station 1 (step S44). For example,
When the slave station 2 is off-hook by the user, call data is transmitted to the master station 1 to connect to the telephone line. If the decision result in the step S44 is "YES", the process moves to a step S61.

On the other hand, if the result of the determination in step S44 is "N
If "O", before transmitting the reception-on notification data to the master station 1, it is determined whether or not a carrier is detected on the control channel (step S45). That is, it waits for the reception of the control data from the master station 1 to end. If the decision result in the step S45 is "YES", a step S42 is executed until no carrier is detected.
Through step S45, and when the determination result is “N
If "O", the reception ON notification data is transmitted to the master station 1 (step S46).

Subsequently, in order to receive the idle channel notification data transmitted from the master station 1, the reception standby state for the control channel is maintained (step S47), and whether the idle channel notification data is received from the master station 1 is determined. A determination is made (step S48). The determination result of step S48 is "NO"
If so, steps S47 and S48 are repeated to wait for reception of free channel notification data.

Then, the free channel notification data is received from master station 1, and the result of determination in step S48 is "YES".
Then, the reception frequency is switched to shift to the corresponding communication channel, and a free channel determination process is performed to determine whether or not the channel is a free channel (step S50). If the result of the determination in step S50 is "YES", the receiving frequency is switched again to shift to the control channel (step S50).
51), and transmits free channel confirmation data to the master station 1 (step S52). Thereafter, in the intermittent reception operation, the state returns from the reception ON state to the reception OFF state (step S55).

On the other hand, if the result of the determination in step S50 is "N
If "O", control is similarly shifted to the control channel (step S53), and instead of free channel confirmation data, channel in-use notification data indicating that the speech channel is in use is transmitted to the master station 1. (Step S54).
Thereafter, the process proceeds to step S47 to wait for reception of new free channel notification data.

Next, a description will be given of a process in the case where the process proceeds from step S43 to step S56 with reference to FIG. First, slave station 2
Receives the control channel (step S56), and
It is determined whether or not free channel designation data has been received from (step S57). If the decision result in the step S57 is "NO", the steps S56 and S57 are repeated to wait for the reception of the empty channel designation data.

On the other hand, if the decision result in the step S57 is "YE
If "S", the slave station 2 immediately transmits the idle channel confirmation data to the master station 1 without performing the idle channel determination processing (step S58). Subsequently, the receiving frequency is switched to the corresponding communication channel (step S59), and when the master station 1 similarly shifts to the communication channel, a predetermined communication process is started (step S60).

Next, with reference to FIG. 9, a description will be given of the processing when the process proceeds from step S44 to step S61. First, the slave station 2 receives the control channel (step S61), and determines whether a carrier is detected on the control channel before transmitting control data to be described later to the master station 1 (step S61). Step S62). If the decision result in the step S62 is "YES", the processes in and after the step S42 are repeated.

On the other hand, if the result of the determination in step S62 is "N
If "O", call data is transmitted to the master station 1 through the control channel (step S63), and it is determined whether or not free channel designation data is received from the master station 1 (step S64). If the decision result in the step S64 is "NO", the steps S63 and S64 are repeated to wait for the reception of the free channel designation data.

On the other hand, if the result of the determination in step S64 is “YE
If "S", the reception frequency is switched to shift to the corresponding communication channel (step S65), and when the master station 1 similarly shifts to the communication channel, a predetermined communication process is started (step S66).

As described above, according to the present embodiment, prior to establishing a wireless connection between the master station 1 and the slave stations 2 and 3, the master station 1 and the slave stations 2 and 3 are set in advance during the intermittent reception. , Both sides of the slave stations 2 and 3 are to confirm the communication channel which is an empty channel. Therefore, when the wireless connection between the master station 1 and the slave stations 2 and 3 is actually established, it can be performed in a short time, and the usability of the cordless telephone system can be improved.

In the above embodiment, the case where the number of slave stations in the cordless telephone system is two has been described. However, the present invention is similarly applied to a cordless telephone system having a larger number of slave stations. Can be applied.

In the above embodiment, the case where the present invention is applied to an analog cordless telephone system has been described. However, the present invention is not limited to this. The present invention can be widely applied to a wireless communication system that performs wireless communication between a master station and a slave station after establishing a wireless connection by a control channel.

[0080]

According to the first aspect of the present invention, both the master station and the slave station determine in advance whether or not the communication channel is an idle channel in the transmission / reception processing. When a connection is established, wireless communication can be started in a short time, and a highly convenient wireless communication system can be realized.

According to the second aspect of the present invention, the above-described transmission / reception processing is performed only when the slave station is charging, so that the increase in power consumption of the slave station can be suppressed while the master station is suppressed. The wireless connection between the mobile station and the slave station can be established in a short time.

According to the third aspect of the present invention, the above-described transmission / reception processing is performed after the slave station repeatedly transmits the reception state notification data to the master station at a predetermined timing. It is possible to acquire information on an empty channel at an appropriate timing when conditions for the empty channel determination are satisfied.

According to the fourth aspect of the present invention, in the intermittent reception, the slave station transmits the reception state notification data to the master station at a timing when the reception state switches from off to on. Thus, it is possible to reliably acquire the information of the empty channel while updating the information on the idle channel for each intermittent reception cycle.

According to the fifth aspect of the present invention, the above-mentioned transmission and reception are performed by performing the intermittent reception operation only when the slave station is charging. Therefore, the slave station adapts to both charging and non-charging. It is possible to acquire necessary information on an available channel at an optimum timing.

According to the sixth aspect of the present invention, at the time of the intermittent reception operation, the slave station randomly sets the timing at which the reception state switches from off to on for each slave station. Even if the transmission of the reception state notification data collides, it is possible to avoid a situation where the transmission repeatedly collides thereafter, and it is possible to reliably transmit and receive the information of the empty channel.

According to the seventh aspect of the invention, when the master station and the slave station establish a wireless connection, the master station transmits the idle channel designation data to the slave station, and the slave station confirms the idle channel that has already been confirmed. Since the wireless connection is established between the master station and the slave station using the determination result of the above, it is not necessary for both the master station and the slave station to judge the available channel, and the operation can quickly proceed to the call operation. This makes it possible to realize a user-friendly wireless communication system.

According to the eighth aspect of the present invention, in the cordless telephone system, the above-described processing is performed, so that an empty channel can be accurately determined, a wireless connection can be quickly established, and high quality can be achieved. In addition, a cordless telephone system that is easy to use can be realized.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a cordless telephone system according to an embodiment of the present invention.

FIG. 2 is a timing chart when transmitting and receiving free channel information between a master station and a slave station.

FIG. 3 is a timing chart in a case where a wireless connection is established between a master station and a slave station when an outside line is received by the master station.

FIG. 4 is a flowchart illustrating a process performed by a master station.

FIG. 5 is a flowchart performed by a master station when call data is received from a slave station.

FIG. 6 is a flowchart performed by a master station when an outside line is received.

FIG. 7 is a flowchart illustrating a process performed by a slave station.

FIG. 8 is a flowchart performed by a slave station when call data is received from the master station.

FIG. 9 is a flowchart performed by a slave station when transmitting call data to the master station.

[Explanation of symbols]

 1 ... master station 2, 3 ... slave station

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoshitsugu Tomomatsu 15-1 Naeshiro-cho, Mizuho-ku, Nagoya, Aichi Prefecture Inside Brother Industries, Ltd. (72) Inventor Tsutomu Ohashi 15-1 Naeshiro-cho, Mizuho-ku, Nagoya-shi, Aichi Prefecture No. F term in Brother Industries, Ltd. (reference) 5K027 AA12 BB01 CC08 EE15 GG04 GG08 JJ01 KK02 5K067 AA15 BB08 CC21 CC22 DD11 DD13 DD23 DD33 DD34 EE02 EE10 GG01 GG11 JJ02 JJ03 JJ12 JJ13 KK06

Claims (8)

[Claims] An information processing apparatus comprising: a master station and one or more slave stations, wherein the master station and the slave station are configured to select one of a plurality of communication channels according to control data transmitted / received via a predetermined control channel. A wireless communication system that performs wireless communication using the communication channel of the above, wherein the master station detects an idle channel from among the plurality of communication channels, Idle channel notification data transmitting means for transmitting, by the control channel, idle channel notification data indicating an idle channel based on the detection result of the idle channel detection means, wherein the slave station transmits the idle channel notification data from the master station. A vacant channel confirmation means for confirming, when received, whether or not the communication channel corresponding to the vacant channel notification data is a vacant channel; A free channel confirmation data transmitting means for transmitting, via the control channel, free channel confirmation data indicating a confirmation result of the free channel confirmation means to the parent station, wherein the empty space between the parent station and the child station is provided. The transmission / reception of the channel notification data and the empty channel confirmation data is repeatedly performed at a predetermined timing. 2. The transmission and reception of the idle channel notification data and the idle channel confirmation data between the master station and the slave station only when the slave station is charging. A wireless communication system as described. 3. The reception status notification data transmitting means for transmitting reception status notification data for notifying the parent station that the free channel notification data can be received to the master station at a predetermined timing through a control channel. The master station, when receiving the reception status notification data from the slave station, transmits the idle channel notification data by the idle channel notification data transmitting means. 3. The wireless communication system according to 2. 4. The mobile station performs an intermittent reception operation on the control channel at a preset time interval during a standby state, and when the mobile station shifts from a reception stop state to a reception operation state during the intermittent reception operation, The wireless communication system according to claim 3, wherein the reception state notification data is transmitted by the reception state notification data transmitting unit. 5. The slave station performs an intermittent reception operation when the mobile station is not charging and continuously performs a reception operation without performing an intermittent reception operation when the mobile station is charging during standby. Item 5. The wireless communication system according to item 4. 6. The mobile station according to claim 1, further comprising a reception timing setting unit that randomly sets a timing of transition from the reception stop state to the reception operation state during the intermittent reception operation for each child station. The wireless communication system according to claim 4 or claim 5. 7. The free channel specifying data for specifying a free channel based on a detection result of the free channel detecting means as a communication channel to be connected to the slave station when establishing a wireless connection with the slave station. Further comprising: an empty channel designation data transmitting means for transmitting the idle channel designation data to the slave station through the control channel. If it is already confirmed that the communication channel corresponding to the designated data is a free channel, the free channel confirmation data indicating the confirmation result is transmitted to the master station by the free channel confirmation data transmitting means, 7. The wireless connection using the communication channel with a master station is established. The wireless communication system according to any one. 8. The wireless communication system according to claim 1, wherein the wireless communication system is a cordless telephone system connected to a telephone line.