JPH0748899B2 - Wireless communication device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a multi-channel access method for detecting an empty wireless channel among a plurality of wireless channels and transmitting / receiving voice or data. The present invention relates to a wireless communication device.

(Prior Art) FIG. 11 is a block diagram showing a conventional configuration of a wireless communication device of this type. In the figure, the parent device 1 is a wireless telephone 2
It is connected to a wireless telephone line and a wired telephone line 3
Connected with.

The signal sent from the wired telephone line 3 becomes the modulation input of the transmitter 5 via the hybrid circuit 4. The radio wave modulated by the transmitter 5 is sent from the transmitting antenna 6 to the wireless telephone 2.

On the other hand, the radio wave transmitted from the wireless telephone 2 is received by the receiving antenna 7 and demodulated by the receiver 8. The demodulated signal is sent to the wired telephone line 3 via the hybrid circuit 4.

The synthesizer 9 outputs the frequency corresponding to the wireless channel to the transmitter 5 and the receiver 8.

One of the outputs of the receiver 8 is input to the reception electric field detection circuit 10 and used for judging the electric field strength. This circuit 10 is generally called a carrier squelch circuit or a noise squelch circuit. The other output is output as a data signal included in the received demodulated wave, and is input to the identification signal detection circuit 11 that collates the identification signal determined by the combination of the parent device 1 and the wireless telephone 2. This identification signal is generally called an ID code.

The outputs of these detection circuits and the demodulated outputs of the data signals are input to the control circuit 12 and used for connection control. Further, the control circuit 12 controls the synthesizer 9 to perform radio channel control, and controls the transmitter 5 to send a transmission data signal as a modulation input.

On the other hand, the wireless telephone 2 also has a receiving antenna 13 and a receiver 1 in the same manner.
4 is provided, and the demodulated output of the receiver 14 is output to the handset 15. Further, the voice input from the transmitter 16 becomes a modulation input of the transmitter 17, and is transmitted by the transmitting antenna 18.

The synthesizer 19, the received electric field detection circuit 20, and the identification signal circuit 21 are equivalent to those in the parent device 1, and the control circuit 22 controls the wireless telephone 2. The speaker 23 is a sounder that emits a ringing tone when an incoming call arrives. In these power systems, the parent device 1 is AC10
The AC plug 24 is connected to 0V, and the output of the rectification stabilizing circuit 25 is used in each circuit. Also, this output is the current control resistor 26,
Rechargeable battery 2 for wireless telephone 2 via charging terminals 27, 28
9 and the output of the battery 29 is used as the power source of the wireless telephone 2.

However, the rough control at the time of incoming call in this conventional example is the 12th
This is performed as shown in the flow chart of the figure.

When the parent device 1 detects the ringing signal from the wired telephone line 3 by the ringing signal detection circuit 30 during standby (34), it sets the oscillation frequency of the synthesizer 9 to the control channel frequency, turns on the transmitter 5, and turns on the incoming signal. Is sent (35). In this case, the incoming signal includes a call channel (S-CH) designation signal.

On the other hand, the wireless telephone 2 turns on the synthesizer 19 for a certain time t1 during standby, sets its oscillation frequency to the control channel frequency, and turns on the receiver 14 (3
6). At this time, when an incoming signal is received (37), the transmitter 1
7 is turned on (38), an incoming call response signal is sent out (39), and the designated communication channel (S-CH) is switched (45). Here, when the incoming signal is not received, the synthesizer 19 and the receiver 14 are turned off for a fixed time t2 (40). Intermittent reception by turning on / off the receiver 14 is called battery saving.

That is, assuming that the current consumption when the receiver is off is Ioff and the current consumption when it is on is Ion, the average current consumption I during standby is I = (1
/ t1 + t2) (t1Ion + t2Ioff), usually Ion >> Ioff
Therefore, I can be reduced.

The parent device 1 receives an electric wave from the wireless telephone 2 and an electric field detection circuit.
When it is detected by 10 (41), sending of the incoming signal is stopped (4
2). At this time, if the radio wave from the wireless telephone 2 is not detected, the incoming signal is continuously transmitted up to a certain number of times (4
3). The fixed number of times is transmitted because the wireless telephone 2 is receiving intermittently, and the signal cannot be received during t2, and the signal may be transmitted longer by 2 signal lengths than t2. The reason for terminating the operation n times is to avoid unnecessary occupation of the control channel when the power supply of the wireless telephone 2 is cut off or the distance is too long.

Next, if the IDs match (44), the S-CH specified in the incoming signal
Switch to. If the IDs do not match, the response is from another set of wireless telephones, so the system waits until there is no call from the wired telephone line 3 (57) and returns to standby.

After switching to S-CH, the parent device 1 sends out a bell ringing signal (47). Upon receiving this (37), the wireless telephone 2 sends a ringing tone from the sounder 23 (49). Therefore, in response to this, when the switch 31 is turned on to go off hook (50), the wireless telephone 2 sends an off hook signal (5).
1), it becomes communication state (50).

On the other hand, when the parent device 1 receives the off-hook signal (52),
The bell ringing signal transmission is stopped (53), the line relay 33 is closed, and a call loop with the wired telephone line 3 is formed to establish a call state (54).

When the number of transmissions reaches n, it is detected that the incoming call from the wired telephone line has ended, and then (56) the process returns to the standby mode to prevent the unnecessary incoming call operation from being performed again.

(Problems to be solved by the invention) By the way, in this type of device, the symbols 1, 2 and 1 ',
As shown by 2 ', a plurality of wired lines 3 may be connected in parallel. Further, as shown in FIG. 14, it is often connected to separate wire lines 3 and 3'in a state of being extremely close to the same house or office via a rosette 58.

However, in such a mode of use, since the parent devices of each group independently detect the idle channel, even if the idle channel is detected in advance during standby from the wireless telephone, the wireless device of each group is not detected. When the telephones make calls at almost the same time, the idle channel is occupied by the group that responds early, and the group that responds late must perform the operation of detecting the idle channel again. There is a problem that the response is delayed.

In addition, when there is an incoming call from the wired line 3 in the configuration of FIG. 13 or two wired lines 3, 3 ′ in the configuration of FIG.
If there is an incoming call from the two devices at almost the same time, the two parent devices 1,1 '
However, there is a problem in that radio waves are sent out on the control channel almost at the same time, and the mutual interference between them causes the line connection with the radio telephones 2, 2'to become impossible.

Furthermore, since each set of wireless communication devices uses a free channel regardless of whether the radio frequency is near or far, the set communication channel may become a channel of an adjacent frequency. Then, when one wireless telephone using the adjacent channel moves to the position of the other wireless telephone and becomes extremely close, interference occurs between the adjacent channels and there is a problem that the call quality deteriorates. .

These problems occur not only when two sets of wireless communication devices are arranged close to each other but also when there are three or more sets.

Such a problem can be solved by providing a common base station for each parent device that manages an empty channel and a call channel. However, since a base station must be provided, a problem arises in that it is economically unsuitable when the number of wireless communication device sets is small.

An object of the present invention is to provide a wireless communication device which has an economical structure and can favorably perform communication in a plurality of sets of wireless communication devices arranged in close proximity.

[Structure of the Invention] (Means for Solving Problems) The present invention achieves the above object by providing information transmitting means for transmitting and receiving information regarding connection control of a wireless line between parent devices of respective wireless communication devices. Has achieved.

(Operation) Information such as an idle channel, a call channel currently in use, and a connection operation start signal is transmitted and received between the parent devices.

Therefore, the parent device can refer to these pieces of information to set a call channel in which interference does not occur or set a connection operation start timing.

(Embodiment) FIG. 1 is a block diagram showing an embodiment of the present invention. A signal input line 60, a signal output line 61 and a ground line are provided in a control circuit 12 of a parent device 1 having a conventional structure, and these lines are provided. As shown in FIG. 2, they are bundled as a cable 62 and connected to the control circuit 12 of the other parent device 1'in the vicinity by the connectors 59 and 59 ', and each signal line is used to connect an empty channel or a communication channel in use. It is configured to send and receive information relating to connection control such as information to and from each other.

The same parts as those in FIG. 11 are represented by the same symbols.

FIG. 3 shows that two sets of parent devices 1 and 1'in such a configuration.
3 is a flowchart showing the operation of the parent device 1 during standby, and if there is no call from the wireless telephone 2 and no call from the wired line 3, the following operation is performed.
That is, first, it is determined whether or not there is an empty channel stored in an empty channel memory (not shown) (step 65), and if there is, a call channel is set to that empty channel (step 66) and reception is performed. Based on the electric field strength, it is determined whether or not an empty channel is actually available (step 67). As a result, when it is actually a free channel, it is checked whether or not the block information regarding the free channel is obtained from another parent device 1 '(step 68). That is, when the wireless telephone 2'paired with the parent device 1'is far from the parent device 1, the parent device 1 is determined to be an empty channel because the electric field strength received from the wireless telephone 2'is weak. Even if it does, another wireless telephone 2'may be using the idle channel. Therefore, when the parent device 1 detects that the empty channel is an empty channel based on the received electric field strength, the empty device determines which empty device has the empty channel depending on whether or not the empty channel blocking information is obtained from another parent device 1 '. 1,
It is detected whether 1'is a free channel that is not used. As a result, if the blocking information from the parent device 1'is not obtained, the initial state at the time of standby is returned to call and receive on the idle channel determined at this time.

However, if the empty channel stored in the empty channel memory is not empty, the blocking information indicating that the channel is in use is transmitted to another parent device 1 '(step 69), and thereafter, new information is added. The operation shifts to the operation of detecting a free channel. Further, even if it is determined that the channel is an empty channel, if the block information is received from another parent device 1 ', this channel cannot be used, and the operation shifts to the detection operation of a new empty channel.

On the other hand, even if no empty channel is stored in the empty channel memory, the operation shifts to a new empty channel detection operation. In the new empty channel detecting operation, first, a random number is generated to randomly detect an empty channel (step 70). Next, whether or not the channel set by the random number is the channel which is to be stored and used as an empty channel in another parent device 1 ′, or whether or not the channel is actually used is transmitted from the parent device 1 ′ via the cable 62. It is judged based on the information sent (step 71). As a result, if the parent device 1'is a channel that is about to be used or is being used, a random number is generated again, and the same empty channel detection is performed again. However, if the channel set by the random number is not the channel to be used by the parent device 1'or the channel actually used, the channel is intermodulated with the channel to be used by the parent device 1 or the channel in use. It is judged whether or not the channel is likely to cause interference (step 72), and if there is a risk of interference, a random number is generated again to shift to a free channel detection operation. However, if there is no fear of interference, the communication channel is set, and it is determined by the received electric field strength there whether or not the empty channel is an unused channel (step 73). As a result, if the channel is not an empty channel, blocking information indicating that the channel is not empty is transmitted to another parent device 1 '(step 7).
4), the empty channel detection operation is performed again by the random number generation.

However, if it is an empty channel, the channel number is stored in the empty channel memory (step 75), and the stored channel number is transmitted to another parent device 1 '(step 76). (CC
Switch to H) and proceed to call confirmation operation (step 77).

In this way, information about the channel that it is trying to use or is currently using is sent to and received from another parent device, and the other parent device interferes with the channel that is scheduled to be used or is being used. By setting a call channel for each parent device and wireless telephone device by detecting an empty channel that does not occur, mutual interference does not occur even when multiple sets of wireless communication devices are placed close to each other. You can make good calls. In addition, an empty channel that is different from the empty channel that is planned to be used or is being used by another parent device is detected and stored, so even if multiple wireless communication devices make simultaneous calls, an empty channel is newly created. The response delay can be eliminated without performing the operation of detecting.

In the free channel detection, the number of free channels stored in the free channel memory is one, but it may be plural. Further, as the information transmitted and received between the parent devices, a known transmission form can be appropriately used.

Further, as shown in FIG. 4, the connection between the parent devices is such that the cables 64 and 64 'bundled together with the wired line are extended to the rosette 63, and the signal lines for transmitting and receiving information are connected within the rosette 63. But it's okay. In this way, it is possible to provide only one connector on each parent device 1, 1 '.

FIG. 5 is a block diagram showing a second embodiment of the present invention. In the embodiment of FIG. 1, the signals 60 and 61 composed of two lines are composed of one signal line 60 'in this embodiment. In addition, two switch circuits 78 and 79 are connected in parallel to this one signal line 60 ', and the switch circuit 78 is normally turned on so that information from another parent device can be received. The switch circuit 78 is turned off and the other switch circuit 79 is turned on only when transmitting information to another parent device. Further, signal lines 82 and 83 for audio signals are added, and switch circuits 80 and 81 are added between these signal lines 82 and 83 and the input of the transmitter 5 and the output of the receiver 8 to obtain By turning on the switch circuits 80 and 81, it is possible to make a call between the wireless telephones without going through the wired line 3. In this case, since the hybrid circuit 4 is not operating, it is necessary to make a sidetone path by the switch circuit 84 and the resistor 85.

FIG. 6 is a block diagram showing a third embodiment of the present invention, in which the low potential side of the diode bridge 86 not shown in FIGS. 1 and 5 is the ground potential of the parent device 1. . With this configuration, the ground potential between the parent devices is connected through the wired line 3,
Only the signal line 60 for transmitting and receiving information can be connected.

FIG. 7 is a block diagram showing a fourth embodiment of the present invention, in which parent devices are connected to each other by a wireless line using weak radio waves instead of connecting a signal line by wire. That is, the information signal output from the signal line 61 is modulated by the transmitter 88 of the transceiver 99 and transmitted to another parent device via the antenna duplexer 89 and the antenna 90. On the other hand, the information signal transmitted from another parent device is received by the receiver 87 via the antenna 90 and the antenna duplexer 89, demodulated, and then input to the control circuit 12 via the signal line 60.

FIG. 8 is a block diagram showing the embodiment of FIG. 5 of the present invention, and FIG. 9 is a flow chart for explaining the operation. This embodiment is different from the embodiment of FIG. 1 in that a detection circuit 94 for detecting radio wave interference during a call by an AM component is provided, and when radio wave interference is detected (FIG. 9, step 9).
5) While the call is being continued, another parent device 1'is requested for free channel information, and the call channel is switched according to the free channel information received from another parent device 1 '(steps 96 to 98). It is designed to continue the call on the call channel. By doing so, the parent device 1 can know a free channel in which interference does not occur in an extremely short time, and can switch channels without making the speaker feel the call cutoff time when switching channels.

FIG. 10 is a flow chart showing a modified example of the empty channel detection operation in the embodiment of FIG. 1, and this example detects an empty channel when an incoming / outgoing call is made, instead of storing the empty channel during standby. To do.
That is, after the random number is generated (step 70), it is determined whether the channel designated by the random number is the channel being used by the parent device 1'or the channel receiving the blocking information from the parent device 1 '(step 91). After confirming that there is no interference (step 72), it is judged by the received electric field strength whether or not the channel is actually a free channel (step 73). After transmitting / receiving to / from the device 1 ', the wireless telephone 2 is instructed to switch the channel to the empty channel (step 93), and the call shifts.

In each of the above-described embodiments, two sets of parent device and wireless telephone are used, but the same can be applied to the case of three or more sets. However, it is necessary to send and receive information regarding line connection control for each parent device at a different timing so that there is no interference or contention.

It can also be applied to a system in which a data terminal for wirelessly transmitting and receiving data is arranged instead of the wireless telephone.

[Effects of the Invention] As described above, according to the present invention, since the wireless line connection is performed by transmitting / receiving the information regarding the wireless line connection control between the parent devices, it is economical without providing an expensive base station. With a simple configuration, good communication can be performed without mutual interference or response delay.

[Brief description of drawings]

FIG. 1 is a block diagram showing the first embodiment of the present invention, and FIG.
FIG. 1 is a block diagram showing the connection relationship between parent devices of FIG.
FIG. 3 is a flow chart for explaining the operation of the embodiment of FIG. 1, FIG. 4 is a block diagram showing another example of the connection form of parent devices, and FIG. 5 is the second embodiment of the present invention. FIG. 6 is a block diagram showing a third embodiment of the present invention, FIG. 7 is a block diagram showing an embodiment of FIG. 4 of the present invention, and FIG. 8 is a block diagram of FIG. 5 of the present invention. A block diagram showing an embodiment,
FIG. 9 is a flow chart for explaining the operation of the embodiment of FIG. 8, FIG. 10 is a flow chart showing a modification of the flow chart of FIG. 3, and FIG. 11 is a block diagram showing the configuration of a conventional wireless communication device. FIG. 12 is a flow chart for explaining the operation of the conventional device of FIG. 11, and FIGS. 13 and 14 are block diagrams showing an example of connection to a wired line when a parent device is placed in proximity. 1 ... Parent device, 2 ... Wireless telephone, 3 ... Wired line, 5,
17 …… Transmitter, 8,14 …… Receiver, 10,20 …… Reception electric field detection circuit, 12,22 …… Control circuit, 58,63 …… Rosette, 59
...... Connector, 60 …… Signal input line, 61 …… Signal output line, 62,64 …… Cable, 78 to 81,84 …… Switch circuit, 86 …… Diode bridge, 87 …… Receiver, 88 ……
Transmitter, 99 …… Transceiver, 94 …… Detection circuit.

Claims (3)

[Claims] 1. A plurality of sets of communication devices each including a parent device connected to a wired line and a terminal device connected to the parent device via a wireless line are arranged close to each other, and the parent device of each communication device is common. A wireless communication device that detects an empty wireless channel from the plurality of wireless channels that are used by the received electric field strength and establishes a wireless line with the corresponding terminal device by using the detected empty wireless channel. The parent device of the device transmits the blocking information including at least the empty wireless channel detected by its own parent device to the parent device of the other communication device, and the other device transmitted from the parent device of the other communication device. Information transmission means for receiving the blockage information including at least an empty wireless channel detected by the parent device of the communication device, and referring to the blockage information received by the information transmission means In the wireless communication device, characterized by a radio channel selecting means for selecting a radio channel to be used. 2. The information transmitting means includes a signal line connecting between the parent devices, and the blocking information is transmitted and received between the parent devices using the signal line. The wireless communication device according to item (1). 3. The wireless communication according to claim 1, wherein the information transmitting means includes a wireless line by a weak radio wave, and the blockage information is transmitted and received through the wireless line. apparatus.