JPH04275729A - Digital moving radio communication system and its channel control method - Google Patents

Abstract

PURPOSE:To offer a digital moving communication system which can effectively use a channel and which can improve user service. CONSTITUTION:The above system is a digital moving radio communication system in which a control means 11 controlling a control channel to be diverted to a call channel when the usable call channel is blocked for a connection device is provided and constituted is set to be a feature in the system which is composed of plural radio moving machines S1-Sn, connection devices Ma-Mn connected with the radio moving machines through a radio line and a controller 1 forming a channel with the plural wire telephone lines; which executes communication between the radio moving machines and the connection devices in terms of time division/multiplex, which uses at least one among plural channels of the radio line for the control channel, and the others for the call channel.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital mobile radio system, and more particularly to a digital mobile radio communication system with improved communication channel control method and its channel control method.

0002

[Prior Art] A mobile radio system is a mobile radio system in which moving individuals, vehicles, etc. are equipped with radio mobile devices, so that they can call and communicate with an existing telephone network or between radio mobile devices at any time by dialing. This system is extremely convenient and has become rapidly popular in recent years.

[0003] Such a digital mobile radio system will be explained. Digital mobile radio systems use time division multiplexing (TDMA) and will be described in conjunction with this.

FIG. 4 is a block diagram of a mobile radio system.
1 is a control device connected to a plurality of telephone networks and forms a communication path with the telephone network; S1 to Sn are wireless connection devices M1 to M
This is a wireless mobile device that can be connected to N via a wireless line and make calls. In addition, wireless connection devices M1 to M
n is a device that is connected to the control device 1 to form a zone and transmits control information and call signals to the wireless mobile devices S1 to Sn in its own zone via a wireless line.

The control device 1 forms a communication path with the telephone network, provides calls from the telephone network to the wireless mobile devices S1 to Sn to the wireless connection devices M1 to Mn, and also receives calls from the wireless connection devices M1 to Mn. Performs various controls such as connecting calls to networks and other wireless mobile devices so that calls can be made.

In FIG. 4, wireless connection devices M1 to Mn
constitute zones A to N, which are service areas, respectively, and control the wireless mobile devices S1 to Sn in their respective zones and transmit call signals from the control device 1. The wireless mobile devices S1 to Sn are wireless telephones, and no matter which wireless connection device M1 to Mn they move into the zone,
It is possible to communicate with the wireless connection devices M1 to Mn at the destination. In addition, wireless mobile devices S1 to S in this system
The control device 1 always knows which zone n exists, and as long as it exists within the zone of this system, it is possible to call and talk.

The control of the wireless mobile devices S1 to Sn performed by the wireless connection devices M1 to Mn includes the control of the wireless mobile devices S1 to Sn.
Zone notification for n, wireless mobile devices S1 to Sn
This includes location registration, outgoing call control, and incoming call control. However, this control is performed by the control device 1, and the wireless connection devices M1 to M
It is also possible to use a method in which n is only relayed.

Next, the TDMA communication system will be explained. There are two main types of TDMA communication methods:
One is the TDMA/TDD method shown in Figure 5, in which transmission and reception are performed alternately by time division, and the other is TDMA/TDD, as shown in Figure 6, in which transmission and reception are performed simultaneously by frequency division.
/FDD method. Both methods divide one frame into several time slots and allocate each time slot between each wireless connection device and wireless mobile device. Both Figures 5 and 6 are examples of dividing into 4 channels, each with T1a-
R1a, T2a-R2a are allocated correspondingly.

[0009] Each of the time slots assigned between the wireless connection device and the wireless mobile device has a digital signal transmission capacity of several tens of kbps, and can transmit control signals or encoded and compressed voice signals. . TDM
Both the A/TDD method and the TDMA/FDD method are methods in which time slots are provided in a time-division manner to configure a channel and allocate it between each device, so there is no difference in the method of allocation. Therefore, from now on, TDMA/TDD
We will proceed with the explanation based on the method.

A conventional communication channel configuration method for this type of device will be explained with reference to FIGS. 4 and 7. FIG. 7 shows the wireless connection device Ma and wireless mobile devices S1 to S5 in zone A in FIG.
This figure shows the communication channel configuration of . In the example in this figure, wireless mobile devices S1 to S3 are on a call, and wireless mobile device S4
and wireless mobile station S5 are on standby.

[0011] Here, a wireless connection device Ma and a wireless mobile device S
The communication channel between 1 and 2 corresponds to the time slots T2a-R2a, and the time slot T2a is used for transmission and the time slot R2a is used for reception. The wireless mobile devices S1 to S3 are T2a-R2a and T3a-R3, respectively.
a, T4a-R4a time slots are used for the call, and T1a-R1a time slots are reserved for communication of zone information and control information such as location registration of wireless mobile devices moving from other zones. This is a control channel. Furthermore, the wireless mobile devices S4 and S5 periodically receive information on time slots T1a-R1a, which are the control channels, in preparation for outgoing and incoming call operations when the communication channel is free. In this example, the control channel is fixed to the T1a-R1a time slot, but there is no problem even if the time slot is changed arbitrarily.

[0012] As described above, according to the conventional communication channel control method, out of all the channels within one frame, one channel is used as a control channel and is dedicated to communication of control information, and the remaining communication channels are used as communication channels within a zone. I use it to talk to wireless mobile devices. Therefore, even if all communication channels are in use among all channels within one frame, only the control channel needs to be kept vacant. Therefore, in this state, if another wireless mobile device in standby attempts to make a call, or if an attempt is made to receive a call to a wireless mobile device in zone A that is in standby, the call will be busy because there are no free communication channels. Therefore, new calls cannot be made or received.

However, when all communication channels are in use, the control channel is only used for position registration of wireless mobile devices, etc., and its frequency of use is small.

[0014]

[Problems to be Solved by the Invention] As mentioned above, in the conventional digital mobile radio communication system, the communication channel control method is such that one channel out of all the channels in one frame is a control channel and is dedicated for communication of control information. The remaining communication channels are used for communication with wireless mobile devices within the zone. Therefore, even if all communication channels are in use among all channels within one frame, only the control channel needs to be kept vacant. Therefore, in this state, if another wireless mobile device in standby attempts to make a call, or if an attempt is made to receive a call to a wireless mobile device in zone A that is in standby, the call will be busy because there are no free communication channels. Therefore, new calls cannot be made or received.

However, when all communication channels are in use, the control channel is only used for position registration of wireless mobile devices, and the frequency of use is small, so effective channel utilization is attempted. I can't say that.

As described above, in the conventional system, it is necessary to always allocate one channel as a control channel among all communication channels within the same zone, and when calls become busy, the control channel is mostly idle. This situation is problematic from the standpoint of user service and channel utilization efficiency.

[0017] Therefore, the purpose of this invention is to
Provided is a digital mobile communication system and its channel control method that allows all communication channels within the same zone to be assigned to speech channels, thereby making it possible to effectively utilize channels and improve user services. It's about doing.

[0018]

[Means for Solving the Problems] In order to achieve the above object, the present invention is constructed as follows. That is, it is composed of a plurality of wireless mobile devices, a connection device that is connected to the wireless mobile devices via a wireless line, and a control device that forms a communication path with a plurality of wired telephone lines. In a system in which communication between a mobile device and a connecting device is carried out by time division multiplexing, and at least one of the multiple channels of a wireless line is used as a control channel and the others are used as communication channels, the first The connection device is provided with a control means for controlling the control channel to be used as a communication channel when an available communication channel is occupied.

[0019] Secondly, when the usable communication channel is occupied, the connection device controls the control channel to be diverted to the communication channel, and in the case of the diversion, the wireless mobile device which is waiting for an incoming call a first control means for controlling the mobile device to notify the diversion, and a second control means for placing the wireless mobile device in a state of waiting for reception of the control channel when the wireless mobile device receives the notification during standby. Configure.

Thirdly, when an available communication channel is occupied, the control channel is diverted to the communication channel.

Furthermore, a fourth feature is that when a control channel is assigned to a communication channel, prior to the assignment, a notification is given to a wireless mobile device that is waiting for an incoming call.

[0022]

[Operation] In the above structure, in the case of the first structure, the control means of the connection device performs control to divert the control channel to the communication channel when the usable communication channel is occupied.

[0023] Furthermore, in the case of the second configuration, the first
The control means controls to divert the control channel to a conversation channel when the usable conversation channel is occupied, and at the time of the diversion, controls to notify the diversion to the wireless mobile device that is waiting for an incoming call. . When the second control means on the wireless mobile device side receives the notification during standby,
Puts itself into a control channel reception wait state.

In the third case, when an available communication channel is occupied, the control channel is diverted to a communication channel.

Furthermore, in the fourth case, when the usable communication channel is occupied, the control channel is diverted to the communication channel, and when the control channel is assigned to the communication channel, before the assignment Notify the machine.

As described above, the present invention uses the control channel as a communication channel when a new call occurs while all communication channels are in use. When a call occurs in
Since the control of the wireless mobile device is switched in such a way that there is no problem in the system, the control channel can be used as a communication channel.

Therefore, according to the present invention, there is provided a digital mobile communication system in which all communication channels can be assigned to speech channels, thereby making it possible to effectively utilize channels and improve user services. and its channel control method.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram showing an embodiment of the present invention. In FIG. 1, 1 is a control device, Ma to M
n is a wireless connection device, and S1 to Sn are wireless mobile devices.

The wireless connection devices Ma to Mn each have zones A to N as service areas, and can control the wireless mobile devices S1 to Sn within their own zones and transmit call signals from the control device 1. . Furthermore, the wireless mobile device S performed by the wireless connection devices Ma to Mn
The control of the wireless mobile devices S1 to Sn includes zone notification to the wireless mobile devices S1 to Sn, location registration of the wireless mobile devices S1 to Sn, origination and call reception control, and the like. However, this control may be performed by the control device 1, and the wireless connection devices Ma to Mn may only perform relaying.

The wireless mobile devices S1 to Sn are wireless telephones, and even if they move into the zone of any wireless connection device Ma to Mn, they can communicate with the destination wireless connection device Ma to Mn. In addition, the control device 1 constantly monitors which zone the wireless mobile devices S1 to Sn in this system are in, and as long as they are in the zone of this system, they can be called and talked. be.

The control device 1 is connected to a plurality of telephone networks, forms communication paths with the telephone networks, and transmits calls from the telephone networks to the wireless mobile devices S1 to Sn to the wireless connection devices Ma to M.
n, and also performs various controls such as connecting calls from the wireless connection devices Ma to Mn to the telephone network or other wireless mobile devices so that calls can be made.

[0032] The wireless connection devices Ma to Mn are control devices (
CPU) 11, time slot detection section 12, receiver section 1
3. It is composed of a PLL synthesizer 14, a transmitter unit 15, a communication interface 16, a duplexer 17, an antenna 18, etc., and each of the wireless mobile devices S1 to Sn has a control unit (CPU) 21, a time slot detection section 22, receiver section 23, PLL synthesizer 24, transmitter section 25,
It is comprised of a duplexer 26, an antenna 27, a call control section 28, a key input section 29, a handset 30, and the like.

The control device (CPU) 11 plays a central role in controlling each element constituting the wireless connection device.
This received signal is demodulated into a digital signal. The time slot detection section 12 detects the time slot of the signal demodulated by the receiver section 13 and notifies the CPU 11 of the time slot, and the PLL synthesizer 14 adjusts the frequencies of the transmitter section 15 and the receiver section 13 to the required frequency. This is a transmission circuit for fixed supply.

The transmitter section 15 modulates and outputs the transmission data from the control device 1 side provided through the communication interface 16, and the modulated transmission signal from the transmitter section 15 is used for both transmission and reception. The signal is sent to the antenna 18 via the receiver 17 for transmission. The communication interface 16 converts a transmission signal (analog or digital) such as an audio signal from the control device 1 side into a protocol and provides it to the transmitter unit 15, and also converts a received signal (analog or digital) from the receiver unit 13 into a protocol. This is a circuit that converts the protocol and sends it to the control device 1. It encodes the audio signal, dial information, etc. to be transmitted and sends it to the transmitter section 15, and the demodulated encoded signal obtained from the receiver section 13 is decoded and controlled. In addition to the function of transmitting signals to the device 1, the transmitter section 15 has functions such as controlling the transmitting signal to be sent to the transmitter section 15 at a required time slot timing.

[0035] Furthermore, the control device (CPU
) 21 plays a central role in controlling each element constituting the wireless mobile device, and also has a function of providing data corresponding to the key to the call control unit 28 in response to key input from the key input unit 29. The receiver section 23 demodulates the received signal received by the antenna 27 and distributed by the duplexer 26 into a digital signal. Time slot detection section 2
2 detects the time slot of the signal demodulated by this receiver section 23 and notifies it to the CPU 21.
The synthesizer 24 is an oscillation circuit that fixes and provides the frequencies of the transmitter section 25 and the receiver section 23 at desired frequencies.

The transmitter section 25 is for modulating the output from the call control section 28, outputting it to the duplexer 26, and sending it to the antenna 27. The key input unit 29 has a dial key, various function keys, etc., and outputs a signal corresponding to the operated key among these keys.The call control unit 28 outputs a signal corresponding to the operated key. The key data from the receiver section 23 is converted into a digital signal and sent to the transmitter section 25, the received data from the receiver section 23 is decoded and control data is sent to the CPU 21, and the audio signal is converted into an analog signal and sent to the handset 30. It controls the

The operation of the present apparatus having such a structure will be explained, but before that, the details of the characteristic parts of the present invention will be explained. In this system as well, the system configuration and operation as a mobile radio communication system are basically the same as in the conventional example. Therefore, the explanation will focus on the different points. A feature of the present invention is a method of controlling communication channels. This will be explained with reference to FIG. 2, which is an operation transition diagram, and FIG. 3, which is a flowchart showing the control procedure of the method of the present invention.

FIG. 2 is an embodiment of the communication channel control method according to the present invention, and is a diagram showing the transition of the channel allocation state between the wireless connection device and the wireless mobile device in zone A of FIG. 4. Here, as in the conventional example, an example is given of a TDMA/TDD communication system with four channels per frame.

First, (a) in FIG. 2 shows the wireless mobile device S1.
This is the channel allocation state when the wireless mobile device S3 is in a call and the wireless mobile devices S4 and S5 are on standby.
1 to S3 are time slots T2a-R2a, T3a
-R3a and T4a-R4a are respectively assigned communication channels, and the wireless mobile devices S4 and S5 receive the control channels of time slots T1a-R1a and are in a standby state.

In addition, the state shown in FIG. 2(b) is similar to the state shown in FIG. 2(a).
), the wireless mobile station S4 newly requests a call and enters the conversation. The procedure at this time is that when the wireless mobile device S4 requests a call, there is no free conversation channel, so it issues an instruction to the wireless mobile device S5 using the control channel to allocate a control channel to the conversation channel. .

[0041] At this time, the wireless mobile device S5 receives the control channel of time slot T1a-R1a, continues to receive the control channel even if no control channel information is found, and responds to the user's call request. Returns busy tone. Thereafter, the control channel is assigned to the wireless mobile station S4 as a communication channel.

In FIG. 2(c), the wireless mobile devices S1, S
3 and S4 are in a talking state, and the wireless mobile device S2 has ended the call and is in standby mode. When the wireless mobile device S2 ends the call, the communication channel becomes vacant, so the channel used by the wireless mobile device S4, which was assigned as the communication channel in the state of (b) in FIG. Make the channel by R1a an empty channel. Then, T1, which became this empty channel,
The time slot of a-R1a is again used as a control channel.

At this time, the wireless mobile devices S2 and S5 have the following:
The channel T1a-R1a is used to notify that this channel has returned to the control channel. Wireless mobile device S5
receives this control channel and enters a normal standby state.

[0044] By allocating all communication time slots under the control of the wireless connection device using such a procedure, economical and efficient communication channel control becomes possible.

Here, in the state shown in FIG. 2B, an instruction is issued to the wireless mobile station S5 to come under the control of a wireless connection device in another zone without issuing an instruction to the wireless mobile station S5, and with this instruction, the wireless mobile station S5 Alternatively, the user may find the control channel of the specified other zone, register the location, and move from one zone to another. Further, in this example, the control channel is physically allocated to the time slots T1a-R1a, but the control channel may use any time slot, or may be flexibly moved between time slots.

The operation of the system shown in FIG. 1 that executes such a communication channel control procedure will be explained below using the flowchart shown in FIG. The wireless connection device monitors whether or not a call has occurred from or to its own zone (S101), and if a call has occurred, it checks whether a communication channel is available (S102). As a result, if there is a free channel, the communication channel is assigned to the call, and it is again monitored whether a call has occurred from or to the own zone (S101).

[0047] If there is no vacancy in S101,
The mobile radio is notified that the control channel of its own zone will be assigned to a communication channel (S103), and the control channel is assigned to the call as a communication channel (S104). After that, it is monitored whether a free channel is created (S105), and if a free channel is created, it is checked whether the free channel is a control channel (S106), and if the free channel is a control channel, the free channel is The channel is restored as a control channel (S108). And again S
Returning to step 101, the occurrence of a call is monitored.

As a result of the check in S106, if the vacant channel is not a control channel, the channel to which the control channel has been assigned as a communication channel is moved to the vacant channel, and the control channel is vacant (S107). Then, the vacant channel is revived as a control channel (S1
08), the process returns to S101 to monitor the occurrence of a call.

[0049] Such control is performed by the wireless connection devices Ma to M.
By having the control device (CPU) 11 of No. n execute this, it is possible to control the diversion of the control channel as a communication channel when the communication channel is blocked, and control the restoration of the control channel when an empty channel occurs.

Next, the operation of the configuration shown in FIG. 1 will be explained. Each of the wireless connection devices Ma to Mn recognizes which wireless mobile device is within its own zone by performing a position acquisition operation with a wireless mobile device within its own zone, and the CPU 11 holds this information. Then, when a call is generated from the telephone network to the wireless mobile device S1 via the control device 1, this call information (including the subscriber telephone number information of the wireless mobile device S1) is sent to each wireless connection device Ma to Mn. It is given to each CPU 11 via its communication interface 16.

[0051] The wireless mobile device S1 to be called is in zone A.
If the wireless connection device Ma that has jurisdiction over zone A
The CPU 11 of the CPU 11 recognizes this, and if there is a free call channel including a control channel, sends this call information to the communication interface 16, which encodes it and determines the timing of the time slot of the control channel. and sends it to the transmitter section 15. The transmitter section 15 modulates this,
It is transmitted from the antenna 18 into zone A. This results in
Call information will be transmitted on the control channel. If there is no free channel, busy information is transmitted to the control device 1 via the communication interface 16.

[0052] The wireless mobile device S1 in zone A has antenna 2.
7, the receiver section 23 demodulates it and outputs it to the call control section 28. Then, since the time slot detection unit 22 detects the timing of the time slot of the control channel, the information on this time slot is transmitted to the CPU 21.
is received from the call control unit 28, and the call information is taken in. Then, it is checked whether this is for itself. As a result, when it recognizes that the call is to itself, it rings a ringer (not shown) to notify that there is an incoming call. The user of the wireless mobile device S1 enters the key input section 29.
When the off-hook switch of the CPU 21 is operated, the CPU 21 recognizes this, stops the ringer, and gives an off-hook signal to the call control unit 28.
8 gives off-hook information to the transmitter section 25 at the timing of the control channel, and the transmitter section 25 modulates this and transmits it from the antenna 27.

The wireless connection device Ma receives this, demodulates it in the receiver section 13, and provides it to the communication interface 16. The communication interface 16 extracts this information at the timing of the control channel, so that the wireless mobile device S
1 off-hook signal is obtained and given to the control device 1. From this, the control device 1 recognizes that the wireless mobile device S1 is off-hook, forms a communication path with the calling side of the telephone network, and enables communication. The wireless connection device Ma thereby uses the available communication channel to exchange voice between the calling side and the called side, thereby carrying out a telephone conversation. When the off-hook signal of the wireless mobile device S1 is obtained, if there is no free communication channel and the control channel is secured, a command is issued to the standby wireless mobile device for zone A, and then the control channel is After securing the communication channel by diverting it to the communication channel, the off-hook signal of the wireless mobile device S1 is given to the control device 1.

[0054] In this way, a communication channel is secured to enable communication. When the control channel is also not available, it becomes busy, and the control device 1 returns a busy tone to the calling party.

[0055] When all the channels are occupied and a call ends in any of the call channels, a call end signal is issued in that call channel, so the CPU 11 of the wireless connection device Ma starts using the free channel. I know that something has happened. Then, if the vacant channel is a control channel, the CPU 11 performs control to restore the vacant channel as a control channel, and gives a command to the mobile wireless device in standby mode. Further, if the vacant channel is not a control channel, the channel to which the control channel is assigned as a communication channel is moved to the vacant channel, and the control channel is vacant. Then, it performs control to restore the vacant channel as a control channel and gives a command to the mobile radio device in standby mode. The CPU 21 of the mobile wireless device in standby mode then starts monitoring the control channel again.

Although the above description has been made regarding calls from the telephone network, the same applies to calls from mobile radios.

As explained above, in the present invention, when a new call occurs while all the communication channels in the same zone are in use, the control channel is used as the communication channel. When a new call occurs while all communication channels in the zone are in use, control information is broadcast to wireless mobile devices within that zone using the control channel, and even if the control channel is temporarily assigned as a communication channel, the system After switching the control of the wireless mobile device to avoid any problems, the control channel is used as a call channel, so in times of congestion, the control channel can be diverted to the call channel and the same effect as adding a call line can be obtained. It has been made possible to do so. In this way, all communication channels can be assigned to call channels, so
The absolute call volume within one zone can be increased, which is economical.

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, but can of course be implemented with appropriate modifications within the scope of the gist; for example, in the embodiments described above. Although the TDMA/TDD communication method has been mainly described, it is also possible to use the TDMA/FDD communication method.
It is also possible to apply a time-division/frequency-division system in which each channel has a different frequency band. In addition, if an empty channel occurs after the control channel is diverted to a speech channel, in the case of the above embodiment, when the control channel is being used as a speech channel, the channel is moved and the control channel becomes an empty channel. In this embodiment, the control channel is restored, but it is also possible to use a method in which the free channel is diverted to the control channel when the free channel is not the original control channel.

[0059]

[Effects of the Invention] As described in detail above, according to the present invention, all communication channels within the same zone can be assigned to speech channels, making it possible to effectively utilize channels and improve user services. It is possible to provide a digital mobile radio communication system and a channel control method therefor that enable the user to achieve the desired goals.

[Brief explanation of the drawing]

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

FIG. 2 is an operation transition diagram for performing the control method of the present invention.

FIG. 3 is a flowchart illustrating a control operation procedure in the example of FIG. 2;

FIG. 4 is a diagram for explaining an overview of a mobile radio system.

[Figure 5] TDMA/TD used in mobile radio systems
A diagram for explaining the D method.

[Figure 6] TDMA/FD used in mobile radio systems
A diagram for explaining the D method.

FIG. 7 is a diagram showing an example of intra-zone transmission/reception timing according to a conventional method.

[Explanation of symbols]

1...Control device, 11, 21...Control device (CPU), 12
, 22... Time slot detection section, 13, 23... Receiver section, 14, 24... PLL synthesizer, 15, 25... Transmitter section, 16... Communication interface, 17, 26... Transmission/reception duplexer, 18, 27... Antenna, 28... Call control unit, 29
...Key input unit, 30...Handset, Ma to Mn...Wireless connection device, S1 to Sn...Wireless mobile device.

Claims (6)

[Claims] Claim 1: A wireless mobile device comprising a plurality of wireless mobile devices, a connection device connected to the wireless mobile devices via a wireless line, and a control device forming communication paths with a plurality of wired telephone lines. , the communication between the wireless mobile device and the connection device is performed by time division multiplexing, and among the multiple channels of the wireless line,
In a system in which at least one is used as a control channel and the other is used as a speech channel, the connecting device has a control means for controlling the control channel to be diverted to a speech channel when the available speech channels are occupied. What is claimed is: 1. A digital mobile radio communication system comprising: [Claim 2] A wireless mobile device comprising a plurality of wireless mobile devices, a connection device connected to the wireless mobile devices via a wireless line, and a control device forming communication paths with a plurality of wired telephone lines. , in a system in which communication between the wireless mobile device and the connection device is performed by time division multiplexing, and in which at least one of a plurality of channels is used as a control channel and the others are used as communication channels; When the usable communication channel is occupied, the control channel is controlled to be diverted to the communication channel, and when the channel is diverted, the first control channel is controlled to notify the diversion to the wireless mobile device that is waiting for an incoming call. A digital mobile radio communication system characterized in that a control means is provided, and the radio mobile device is provided with a second control means for placing itself in a state of waiting for reception of a control channel when receiving the notification during standby. . 3. A wireless mobile device comprising a plurality of wireless mobile devices, a connection device connected to the wireless mobile devices via a wireless line, and a control device forming communication paths with a plurality of wired telephone lines. , in a system in which communication between the wireless mobile device and the connecting device is performed by time division multiplexing, and in which at least one of a plurality of channels is used as a control channel and the others are used as communication channels; A channel control method for a digital mobile radio communication system, characterized in that when a channel is blocked, a control channel is diverted to a speech channel. 4. The channel control method for a digital mobile radio communication system according to claim 3, wherein when a control channel is assigned to a communication channel, a radio mobile device waiting for an incoming call is notified before the assignment. 5. The digital mobile radio channel control method according to claim 4, wherein the radio mobile device that has received the notification of communication channel assignment of the control channel is put into a state of waiting for reception of the control channel. 6. A wireless mobile device that receives communication channel allocation information of a control channel searches for a control channel of another wireless connection device and comes under the control of this wireless connection device. 4. The digital mobile radio channel control method according to 4.