JPH04213933A - Digital cordless telephone set - Google Patents

Abstract

PURPOSE:To attain direct talking between slave sets not through a master set by means of a single frequency CONSTITUTION:An idle speech channel is acquired based on a call detection output from a call detection means 20 for inter-slave set direct talking and an inter-slave set direct connection request signal including information of the speech channel is sent directly to an opposite slave set. Then a synchronizing signal to set a transmission reception slot is sent to the opposite slave set and the opposite slave set based on the information sets a speech channel for inter- slave set direct talking and sets the transmission reception slot. The transmission slot and the reception slot which differ timewise are set and the inter-slave set direct talking is implemented by using one transmission reception frequency.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to digital cordless telephone equipment, and more particularly to technology for communicating between handsets.

0002

[Prior Art] For example, a digital cordless telephone device used in a telepoint system, etc. consists of a master unit (base station) connected to an exchange via a line, and a plurality of wireless slave units (mobile stations). However, the TDD method and the TDMA/TDD method are generally used as a wireless transmission/reception method between these devices.

[0003] In the TDD system, as shown in FIG. 13A, a transmission slot T and a reception slot R are alternately repeated.
A so-called ping-pong transmission is performed.

Further, in the TDMA/TDD system, as shown in FIG. 13B, one frame is composed of a plurality of, for example, four transmission slots T1 to T4 and the same number of reception slots R1 to R4, and slot T1 and R1, T
2 and R2, T3 and R3, and T4 and R4 are used in pairs for transmission and reception.

[0005] These transmission/reception systems have the advantage that the transmission frequency and the reception frequency can be the same frequency because transmission and reception are performed temporally separated in the transmission slot and the reception slot.

[0006] Conventionally, in this type of digital cordless telephone device, calls between slave units are relayed through the base unit.

For example, as shown in FIG. 14, in the case of the TDD system, in order to make a call between handset MS1 and handset MS2, two different frequencies f1 and f2 are used to communicate with the exchange via line L. The broadcast is relayed by the base unit BS connected to the base unit BS. That is, between the base unit BS and the slave unit MS1, transmission slots T and reception slots R are allocated as shown in FIGS. 15A and 15B, and the transmission and reception frequency is f1 for transmission and reception. Further, between the base unit BS and the slave unit MS2, transmission slots T and reception slots R are allocated as shown in FIGS. 15C and 15D, and transmission and reception are performed with the transmission and reception frequency set to f2. By transmitting and receiving data via this base unit BS, a telephone conversation is performed between slave units MS1 and MS2.

On the other hand, in the case of TDMA/TDD system,
As shown in FIG. 16, in the same way, the base unit BS is relayed to
A call is made between S1 and MS2, and only one frequency, for example f1, may be used. However, the slots used are changed between the base unit BS and the slave unit MS1, and between the base unit BS and the slave unit MS2. That is, for example, as shown in FIGS. 17A and 17B, between the base unit BS and the slave unit MS1, transmission and reception is performed at the transmitting/receiving frequency f1 using the pair of transmission slot T1 and reception slot R1. As shown in FIGS. 17A and 17C, transmission and reception is performed between the slave unit MS2 and the slave unit MS2 via the base unit BS using the pair of transmission slot T2 and reception slot R2 at the same transmission and reception frequency.
This is for communicating between S1 and MS2.

[0009]

[Problem to be solved by the invention] However, TDD
In the case of digital cordless telephone devices using the BS method, two frequencies must be used for calls between handsets, so the base unit BS
had the disadvantage that two wireless transmitter/receivers were required, making the device complex. Furthermore, two frequencies are occupied, which poses a problem in terms of effective frequency utilization.

[0010] On the other hand, in the case of a TDMA/TDD type digital cordless telephone device, only one transmitting/receiving frequency is required for communication between slave units, so only one wireless transmitting/receiving section of the base unit BS is required. , slots must be relayed, which also makes the device complicated. Furthermore, since two pairs of slots are used for communication between handsets, the number of empty slots decreases, and there is a problem in that opportunities for other handsets to talk are reduced.

Furthermore, with both methods, it is not possible to communicate between handsets while the base unit is in use or in a place where there is no base unit, and when the number of handsets increases, the communication system between handsets becomes complicated. , the disadvantage is that the control for that purpose is also complicated.

SUMMARY OF THE INVENTION In view of the above points, it is an object of the present invention to provide a digital cordless telephone device that allows telephone calls to be made between slave units without the need for relaying through a base unit.

[0013]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention provides a digital cordless wireless communication system that is composed of a base unit and a plurality of slave units, and that performs calls by making transmission and reception different in time. In the telephone device, each handset includes means for capturing an empty communication channel when making a direct call between two-way handsets, and at least information indicating the captured empty channel and identification information of the other handset. means for transmitting a direct connection request signal between slave units to the other slave unit; and means for transmitting a direct connection request signal between slave units to the other slave unit; a determining means for determining whether or not a call channel specified by channel information is an empty channel; and means for transmitting a synchronization signal for setting a transmission period and a reception period when receiving the direct connection permission signal between handsets. .

Further, in the invention of claim 2, each handset has at least the voice transmission control operation means, the means for capturing an empty communication channel when a one-way direct simultaneous call between handsets is made, and at least means for transmitting, to other slave units, a direct simultaneous connection request signal between slave units including information indicating the captured vacant channel; and means for transmitting the direct simultaneous connection request signal between slave units to other slave units; a means for transmitting a synchronization signal for transmission and reception; and a means for setting a communication channel to be set based on information of an empty channel included in the signal when receiving the direct simultaneous connection request signal between the handsets; means for receiving a synchronization signal and synchronizing transmission and reception;
means for detecting an audio output operation of the audio output control operating means after transmitting the synchronization signal for transmission and reception, and transmitting the audio signal to another handset using the captured communication channel; and the audio output control. and means for detecting a voice non-sending operation of the operating means and transmitting a one-way inter-slave unit call termination signal to other slave units via the communication channel.

[0015]

[Operation] In the invention of claim 1, between slave units,
A communication channel is directly established, and transmission slots and reception slots are allocated, and two-way direct communication between handsets is performed directly on one frequency.

[0016] In the invention of claim 2, a one-way call is made directly from one handset to another handset using a vacant communication channel.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a digital cordless telephone device according to the present invention will be described with reference to the drawings.

[Example of direct communication between two-way slave units] FIG. 2 shows a conceptual diagram of the first embodiment of the present invention, in which each slave unit (mobile station) MS1, MS2,... and the line Calls with other parties connected to L (including cordless telephone devices) are carried out via the main unit (base station) BS, just as in the past, but for example between handsets MS1 and MS2. A call is made directly between these handsets MS1 and MS2 using one transmission/reception frequency f1, with the relationship between the transmission slot T and the reception slot R as shown in FIG. Therefore, each slave device MS1, MS2, . . . is configured as follows.

FIG. 4 shows an example of the configuration of each handset in this example, where 1 is an antenna, 2 is a transmission/reception changeover switch, 3 is a radio reception section, 4 is a demodulation section, and 5 is a radio transmission section. ,6
is a modulation unit, 7 is a communication control unit, 8 is a voice encoding/decoding unit,
9 is a speaker as a receiver, 10 is a microphone as a transmitter, and 11 is various key input operation units.

[0020] The communication control section 7 performs switching control of whether the channel to be used is a control channel or a communication channel, and control of switching between transmission and reception. For example, when making a call or receiving a call, key input from the key input operation section 11 and demodulation section 4 are performed.
In response to the output, it forms various command signals to be sent to the other party, and also controls the receiving section 3, the transmitting section 5, and the transmitting/receiving changeover switch 2 to perform call origination control and incoming call control. Further, in order to determine the timing of transmission and reception, a transmission slot T and a reception slot R are set.

[0021] Then, when the call state is established, the communication control section 7
controls the switch 2, the receiver 3, and the transmitter 4 in synchronization with the set transmission slot T and reception slot R. Therefore, the audio signal from the microphone 10 encoded by the audio encoding/decoding unit 8 is sent to the communication control unit 7, the modulation unit 6
, transmitter 5, switch 2, and antenna 1 to the other party in sequence during transmission slot T.
Sent in In addition, a received signal transmitted from the other party at frequency f1 during the reception slot R is received by the antenna 1, and is audio-encoded via the switch 2, the receiver 3, the demodulator 4, and the communication controller 7. The decoding unit 8 decodes the audio signal, reproduces the audio signal, and supplies the audio signal to the speaker 9.

[0022] The communication control unit 7 is constituted by a microcomputer, and direct two-way communication between handsets is executed by a software program.

FIG. 1 shows an example of the configuration of the communication control section 7 for performing direct communication between handsets. When the communication control section 7 is constituted by a microcomputer, each means indicates a function executed by a software program.

That is, in the example of FIG. 1, each handset includes a call detection means 20 for bidirectional direct communication between handsets, a partner handset identification means 21, an empty channel acquisition means 22, and
A direct connection request signal forming means 23, an encoding means 24, a wireless control means 25, a decoding means 26,
A direct connection permission signal forming means 27, a synchronizing signal forming means 28, and a call termination signal forming means 29 are provided.

[0025] The call detection means 20 includes the key input operation section 11
It receives a key input operation output from , detects a call key input operation for direct communication between two-way handsets, and supplies the call detection signal to the wireless control means 25 .

[0026] The partner handset identifying means 21 receives the key input operation output from the key input operation section 11, detects the number of the handset of the other party with whom you wish to make a direct call, and identifies the handset number of the other party (for example, the identification code of each handset). Direct connection request signal forming means 23 between slave units
supply to. Note that each handset is given a different handset identification code (hereinafter referred to as a handset ID) in advance.

The vacant channel acquisition means 22 receives a command from the wireless control means 25, searches the frequency of radio waves used in the vicinity of its own handset, and selects a vacant channel among the plurality of communication channels. Select and capture. Then, this empty channel capturing means 22 supplies information as to whether or not an empty channel has been captured to the radio control means 25, and when capturing an empty channel, information indicating the captured empty channel, such as the channel number. is supplied to the slave unit direct connection request signal forming means 23.

The inter-slave device direct connection request signal forming means 23 includes:
Receiving the vacant channel number from the vacant channel acquisition means 22 and the partner handset ID from the partner handset identification means 21,
A direct connection request signal between handsets is formed including at least this information and the own ID of the handset, and this direct connection request signal between handsets is supplied to the encoding means 24 under the timing control of the wireless control means 25.

The encoding means 24 receives a direct connection request signal between handsets from the direct connection request signal forming means 23, a direct connection permission signal between handsets from the direct connection permission signal forming means 27, and a synchronization signal. It receives the synchronization signal from the forming means 28 and the end signal of the direct call between two-way handsets from the end-of-call signal forming means 29, converts these signals into the signal format of a command signal to be described later, and sends the signal to the wireless control means 25. The signal is sent to the modulation section 6 according to the control. It also receives encoded audio from the audio encoding/decoding section 8 and sends it to the modulating section 6 under the control of the radio control means 25 .

The radio control means 25 receives the call detection output from the call detection means 20, the information as to whether or not an empty channel has been captured from the empty channel acquisition means 22, the synchronization signal from the synchronization signal forming means 28, and the termination signal from the synchronization signal forming means 28. In response to a call end signal etc. from the talk signal forming means 29, a switching control signal is supplied to the transmission/reception changeover switch 2 in order to switch between a control channel and a speech channel and to control channel frequency selection. A signal is supplied to the transmitter 5 to control its operation. Further, the wireless control means 25 includes a direct connection request signal forming means 23 between handsets, a direct connection permission signal forming means 27 between handsets, a synchronization signal forming means 28, and a call termination signal forming means 29.
control the output signal timing of Further, the encoding means 24 and the decoding means 26 include command signal processing,
Provides a switching signal for audio signal processing.

The decoding means 26 receives the command signal and voice data from the demodulation section 4, and supplies the voice data to the voice encoding/decoding section 8. In addition, as a result of decoding the input command signal, if the own handset ID is included and the command signal is a direct connection request signal between handsets, information indicating this and information between handsets The wireless control means 2 transmits the call channel number included in the direct connection request signal.
5, decodes the partner handset ID included in the received inter-handle direct connection request signal, and supplies the partner handset ID to the inter-handle direct connection permission signal forming means 27. Further, when the command signal is a direct connection permission signal between handsets, information indicating this is supplied to the wireless control means 25 and also to the synchronization signal forming means 28.

[0032] The inter-slave device direct connection permission signal forming means 27 includes:
In response to the drive signal from the wireless control means 25, a direct connection permission signal between handsets is formed, which includes the partner handset ID from the decoding means 26 and the own handset ID, and this is sent to the wireless control means 25. Encoding means 24 according to timing control
supply to.

The synchronizing signal forming means 28 is the decoding means 2
6, forms a synchronization signal for setting the transmission slot T and reception slot R, supplies it to the radio control means 25, and encodes the synchronization signal according to the timing control of the radio control means 25. Means 24 is supplied.

The end-of-call signal forming means 29 receives the end-of-call key input operation output from the key input operation unit 11, detects the end of the call, and supplies the end of the call detection signal to the wireless control means 25,
A termination signal for a direct call between two-way handsets is formed, and this termination signal is sent to the encoding means 24 under timing control by the wireless control means 25.

FIG. 5 shows an example of the signal format of the command signal. The command signal in this example has a bit synchronization signal BSYN at the beginning, followed by a frame synchronization signal FS.
Has YN. Furthermore, the command signal includes a system identification code SYID, an error correction code ECC for this code SYID, and a dummy bit DMIT following the frame signal FSYN, and a control code of, for example, 5 bytes following the dummy bit. It has CTRL. In this case, the control code CTRL is a code whose first byte indicates control content, eg, a request for direct connection between handsets, permission for direct connection between handsets, synchronization, end of call, etc. The second to fifth bytes contain parameters or data related to the first byte, such as the own handset ID, the other party's handset ID, and an empty channel number.

[0036] The operation when a device having the above configuration is used to conduct a two-way direct communication between handsets MS1 and MS2, for example, will be explained with reference to a flowchart showing the communication procedure in FIG. .

In FIG. 6, for example, the slave MS is on the left side.
1, and the right side shows the operation of slave unit MS2, respectively.
The leftmost and rightmost flows, respectively, are connected to the control channel (control C
The middle flow in each of the operations related to H) shows the operations related to the communication channel (communication CH).

Now, when a calling operation for a two-way direct call between handsets is performed on the key input operation section 11 of the handset MS1,
In response to this key input operation, the call detection means 20 detects a call for direct communication between two-way handsets (step 101). This call detection output is supplied to the radio control means 25, and the radio control means 25 drives the idle channel acquisition means 22. The vacant channel acquisition means 22 is an own slave MS.
An empty channel is selected from among a plurality of communication channels at the location of 1 (step 102), and captured (step 103). Then, information indicating whether or not the channel has been captured is supplied to the radio control means 25, and when an empty channel is captured, information indicating the captured empty channel, that is, the channel number, is sent to the inter-mobile direct connection request signal forming means 23. supply to.

[0039] Furthermore, the handset number of the person with whom the user wishes to talk, which is inputted by key input operation, is detected by the handset identification means 21, and the detected handset ID of the other person is sent to the direct connection request signal forming means 23. Supplied.

Then, the radio control means 25 detects an empty control channel and sets the control channel to the transmitter 5 (step 104). Then, under the timing control of the wireless control means 25, the inter-slave device direct connection request signal forming means 23 generates an inter-slave direct connection request signal including the vacant channel number, the other child's ID, and its own child device ID to the encoding means 24. supply to. Therefore, the slave unit MS1 transmits this direct connection request signal between slave units to the slave unit MS2 via the control channel (step 1
05).

On the other hand, the handset MS 2 receives this direct connection request signal between handsets (step 202) in the standby state (step 201), and decodes it in the decoding means 26. Then, when the received handset-to-handset direct connection request signal includes the handset ID of the handset MS2, the decoding means 26 indicates to the wireless control means 25 that it is a direct connection between handsets. supply the signal. The wireless control means 25 is
In response to this, the idle channel acquisition means 22 detects the communication channel number included in the direct connection request signal between slave units.
This slave unit MS2 is also given a command to search for an empty channel. The empty channel acquisition means 22 sends the result to the radio control means 25. If the search results in an empty channel, the wireless control means 25 sets the transmitter 5 and the receiver 3 to the frequency of the empty communication channel.

Further, the decoding means 26 supplies the slave unit ID of the partner slave unit MS1 to the slave unit direct connection permission signal forming unit 27. In response to this, the inter-slave device direct connection permission forming means 27 forms an inter-slave device direct connection permission signal, and transmits this to the encoding means 2 according to the timing control of the wireless control means 25.
Send to 4. In this way, slave unit MS2 sends this direct connection permission signal between slave units back to slave unit MS1 via the communication channel (step 204).

The slave unit MS1 receives this direct connection permission signal between slave units, and detects it with the decoding means 26 (step 1).
06). The decoding means 26 drives the synchronization signal forming means 28 to form a synchronization signal for setting the transmission slot T and the reception slot R, and sends this synchronization signal to the radio control means 25 and the encoding means 24. Then, the wireless control means 25 sends this synchronization signal from the encoding means 24 to the modulation section 6, and sends it to the partner handset MS2 (step 107).

[0044] The slave unit MS2 receives this synchronization signal and (
Step 203), the decoding means 26 detects the synchronization signal and sends the detected synchronization signal to the wireless control means 25. The radio control means 25 thereby controls the transmission slot T and the reception slot R.
Detecting this, the slave unit MS2 synchronizes transmission and reception with the slave unit MS1.

In this way, a communication channel is established between handset MS1 and handset MS2, and transmission slot T and reception slot R are set. Therefore, a single frequency of this captured communication channel, e.g. A two-way conversation takes place (steps 108 and 206).
).

[0046] As a result of the carrier sense in step 203, if the designated communication channel is not an empty channel, the direct connection permission signal between handsets MS2 is not sent to handset MS1, and the direct connection permission signal between handsets is not transmitted from handset MS2 to handset MS1. Two-way communication will not be established.

In the above-mentioned state of direct two-way communication between the handsets, when the end key is operated on the key input operation section 11 of the handset MS1, the end of the call signal is generated by the end of the call signal forming means 29.
A call end detection signal is supplied to the radio control means 25, and a call end signal is formed, which is supplied to the encoding means 24. Then, the handset MS1 transmits the end-of-call signal from the encoding means 24 to the other handset MS2 (step 109).

[0048] The handset MS2 receives this call termination signal, and
It is detected by the decoding means 26 (step 207). Then, a call end response signal forming means (not shown) is driven to form a call end response signal, and this is transmitted under the control of the wireless control means 25.
It is sent back to slave unit MS1 via encoding means 24 (step 208). The slave unit MS1 receives this and detects it using the decoding means 26 (step 110).

Thereafter, the wireless control means 25 of the handsets MS1 and MS2 performs call termination control, and both enter the standby state (steps 111 and 209).

[Embodiment of one-way direct simultaneous communication between slave units] FIG. 7 shows a conceptual diagram of a second embodiment of the present invention. In this example,
Calls between each handset (mobile station) MS1, MS2, ... and the other party connected to line L are carried out via the base unit (base station) BS, just as in the past. For example, when transmitting a message, one handset MS1 can directly send a unidirectional call to all other handsets MS2, MS3, etc. using a single transmitting/receiving frequency, for example, f1. It is something to do. For this reason, each slave unit MS1, MS2
,... are constructed as follows.

That is, FIG. 8 shows an example of the configuration of each handset in this example, and in addition to the hardware configuration of the example in FIG. As an example of means, a press talk switch 12 is provided for the communication control section 7. In this example, a one-way direct call between handsets is selected by key input operation, and when this one-way direct call between handsets is selected, as will be described later,
While the press talk switch 12 is turned on, one-way simultaneous calls such as voice message transmission can be made directly to other handsets.

FIG. 9 shows an example of the configuration of the communication control section 7 for carrying out direct simultaneous communication between one-way slave units in this example. When the communication control section 7 is constituted by a microcomputer as in the above example, each means indicates a function executed by a software program.

That is, in the example of FIG. 9, each handset has a one-way simultaneous call mode detection means 30, an empty channel acquisition means 31, an inter-slave direct simultaneous connection request signal forming means 32, and a synchronization signal. a forming means 33, an encoding means 34, a wireless control means 35, a decoding means 36, an on/off detection means 37 for the press talk switch 12,
A call termination signal forming means 38 is provided.

The one-way simultaneous call mode detection means 30 receives the key input operation output from the key input operation unit 11, detects when an input key operation for one-way simultaneous call is performed, and performs one-way simultaneous call. The mode detection signal is transmitted to the wireless control means 35.
Output to. In response to this, the wireless control means 35 enters a mode for performing wireless control for one-way simultaneous communication. The unidirectional simultaneous call mode detecting means 30 further detects when the calling key is operated and supplies a calling detection signal to the radio control means 35.

[0055] In response to a command from the radio control means 35, the vacant channel acquisition means 31 searches for the frequency of radio waves used in the vicinity of its own handset, in the same manner as in the above example, and performs multiple calls. Select and capture an empty channel. Then, this empty channel capturing means 31 supplies information as to whether or not an empty channel has been captured to the radio control means 35, and when capturing an empty channel, information indicating the captured empty channel, such as the channel number. is supplied to the slave unit direct simultaneous connection request signal forming means 32.

Direct simultaneous connection request signal forming means 32 between slave units
receives an empty channel number from the empty channel acquisition means 31, forms a direct simultaneous connection request signal between slave units including at least this empty channel number, and supplies this direct simultaneous connection request signal between slave units to the encoding means 34. .

The encoding means 34 receives a direct simultaneous connection request signal between the handsets from the handset direct simultaneous connection request signal forming means 32, a synchronization signal from the synchronization signal forming means 33, and a termination signal from the call termination signal forming means 38. receives speech signals, converts these signals into the signal format of the command signal described above,
The signal is sent to the modulation section 6 under the control of the radio control means 35. It also receives the encoded audio from the audio encoding/decoding unit 8 and transmits it to the modulating unit 6 under the control of the radio control unit 35.
Send to.

[0058] The wireless control means 35, as in the above example,
It performs selection control between a control channel and a communication channel, and also controls the operations of the encoding means 34 and the decoding means 36. It also supplies a switching control signal to the transmission/reception changeover switch 2, and further supplies a signal to the receiving section 3 and transmitting section 5 to control their operations.

The decoding means 36 receives the command signal and audio data from the demodulating section 4, and supplies the audio data to the audio encoding/decoding section 8. Furthermore, if the input command signal is decoded and it is a request signal for direct simultaneous connection between slave units, information indicating this fact is supplied to the wireless control means 35. In response to this, the wireless control means 35
The handset is placed in a one-way direct call mode between handsets, and the wireless channel is controlled to be switched from the control channel to the call channel.

Further, when the decoding means 36 receives a synchronization signal as a command signal in the one-way handset direct simultaneous communication mode, it sends this synchronization signal to the radio control means 35. The radio control means 35 sets the transmission slot T and the reception slot R.

The on/off detection means 37 of the press talk switch 12 supplies the radio control means 35 with an on/off detection output indicating whether the press talk switch 12 is on or off. The radio control means 35 detects the start of sending a voice message and the end of a voice message from the on/off detection output of the press talk switch 12, and drives and controls the synchronization signal forming means 33 and the end of a call signal forming means 38.

[0062] The synchronization signal forming means 33 transmits the transmission slot T.
and reception slot R, and supplies the synchronization signal to the encoding means 34 and to the radio control means 35.

The collective call termination signal forming means 38 receives a command from the radio control means 35, forms a call termination signal, and sends this call termination signal to the encoding means 34 according to the timing control of the radio control means 35. .

[0064] The operation when performing a one-way direct simultaneous call between slave units using the device configured as described above will be described below.For the sake of simplicity, for example, from slave unit MS1 to slave unit
A case where a one-way call is made directly between handsets will be described with reference to a flowchart showing a communication procedure in FIG. 10.

In FIG. 10, the left side is, for example, the slave unit M.
The right side shows the operation of S1, and the right side shows the operation of slave unit MS2. The leftmost and rightmost flows respectively show the operations related to the control channel, and the middle flow shows the operations related to the communication channel.

[0066] Now, when the key input operation section 11 of the slave unit MS1 performs a calling operation for a direct one-way simultaneous call between the handsets, the one-way simultaneous call mode detecting means 30 receives this key input operation. A direct one-way simultaneous call between handsets is detected (step 121). This call detection output is supplied to the radio control means 35, and the radio control means 35 drives the idle channel acquisition means 31. The empty channel acquisition means 31 selects an empty channel from among a plurality of communication channels at the location where its slave unit MS1 is present (step 1).
22) and capture it (step 123). and,
In addition to supplying information as to whether or not a free channel has been captured to the wireless control means 35, if a free channel is captured, information indicating the captured free channel, that is, the channel number, is supplied to the direct simultaneous connection request signal forming means 32 between slave units. supply

[0067] Then, the radio control means 35 detects an empty control channel and sets the control channel to the transmitter 5 (step 124). Then, under the timing control of the wireless control means 35, the direct simultaneous connection request signal between slave units 32 supplies the direct simultaneous connection request signal between slave units including at least the vacant channel number and the own slave unit ID to the encoding means 24. do. Therefore, the slave unit MS1 receives this direct simultaneous connection request signal between slave units,
It is transmitted to the slave unit MS2 and other slave units via the control channel (step 125).

On the other hand, the handset MS2 etc. (including other handsets, the same applies hereinafter) is in the standby state (step 211).
This direct simultaneous connection request signal between slave units is received (step 2).
12), decoded by the decoding means 36. When the decoding means 36 detects that the decoded command signal is a request signal for direct simultaneous connection between slave units, the decoding means 36 supplies a signal indicating direct simultaneous connection between slave units to the wireless control means 35 of the slave unit. do. In response to this, the wireless control means 35, for example, drives a ringer to notify the users that there is a simultaneous connection request, and also sets the transmitting section 5 and receiving section 3 to the frequency of the vacant communication channel, Handset M
S2 enters a standby state for receiving a signal sent via the communication channel from handset MS1.

On the other hand, the wireless control means 35 of the slave unit MS1:
After sending a direct connection request signal between handsets, perform control to switch from the control channel to the captured communication channel (
Step 126). Then, the wireless control means 35 drives the synchronization signal forming means 33. In response to this, the synchronization signal forming means 33 forms a synchronization signal for setting the transmission slot T and the reception slot R, and sends this synchronization signal to the radio control means 35 and the encoding means 34. Then, by the wireless control means 35, the slave unit MS1 sends this synchronization signal from the encoding unit 34 to the modulation unit 6, and sends it to the partner slave unit MS2, etc. (step 127).

The handset MS 2 and the like receive this synchronization signal (step 213 ), detect it with the decoding means 36 , and send the detected synchronization signal to the radio control means 25 . The radio control means 25 thereby detects the transmission slot T and the reception slot R, and the slave unit MS2 and the like can synchronize transmission and reception with the slave unit MS1.

[0071] In this way, a communication channel is established between the handset MS1, handset MS2, etc., and a transmission slot T and a reception slot R are set.

When the press talk switch 12 is turned on, this is detected by the on/off detection means 37. This ON detection output is supplied to the wireless control means 35, and the control operation of the wireless control means 35 causes the slave unit MS1 to be in a state where it can transmit audio. That is, the voice message inputted from the microphone 10 is sent out all at once from the antenna 1 to other handset MS2 etc. via the encoding/decoding section 8, the encoding means 34, the modulating section 6, and the transmitting section 5. (Step 128), the handset MS2 etc. receive this voice message (Step 214). Therefore, this voice message can be reproduced and listened to by the speaker 9 in the handset MS2 and the like. In addition, in consideration of the case where the user handset on the receiving side does not want to receive the message of this one-way broadcast call, a one-way broadcast call suppression switch is installed.
Emission of sound from the speaker 10 may be suppressed.

[0073] Then, when the handset MS1 finishes transmitting the voice message etc. and turns off the press talk switch 12, the on/off detection means 37 of the handset MS1 detects this and transmits the off detection signal wirelessly. It is supplied to the control means 35. Then, the radio control means 35 drives the all call termination signal forming means 38 to output the all call termination signal. Therefore, the handset MS1 sends this all call termination signal to other handsets MS2, etc. (step 129), and the handset MS2, etc. receive this all call end signal (step 215).
) In this state, each handset MS1, MS2, ... does not immediately end the call, but for example, for a preset period of time, the handset MS1, MS2, ... performs a simultaneous call in the one-way handset-to-handset direct call mode. Goes into standby mode. When the press talk switch 12 is turned on, for example, in the handset MS2 within this predetermined time, the wireless control means 35 receives a synchronization signal in response to the on/off detection signal from the on/off detection means 37. The forming means 33 is driven and a synchronization signal is sent from this slave unit MS2 to other slave units (step 216). Other handset MS
The 1st etc. receives this synchronization signal (step 130) and sets the transmission slot T and reception slot R. Then, when a voice message is subsequently sent from the MS2 (step 217), the slave unit MS1 etc. receives this voice message (step 131). Then, when the press talk switch is turned off, a call end signal is sent from the handset MS2 to the handset MS1, etc., as described above, and the one-way call ends once.

[0074] Similarly, within the predetermined time,
By turning on the press-talk switch 12 of any handset, the handset whose press-talk switch 12 is turned on can perform a one-way simultaneous call to other handsets. In this case, in the direct unidirectional simultaneous call mode between handsets, if the synchronization relationship between transmission and reception once established is not disrupted, the transmission and reception of synchronization signals during the second and subsequent unidirectional simultaneous calls will not be possible. It may be omitted.

[0075] In this way, by turning the press talk switch 12 on and off by each handset at different times, it is possible to directly talk between three or more handsets using this unidirectional simultaneous call method. It can be carried out.

FIG. 11 shows the relationship between transmission and reception slots during direct one-way simultaneous communication between handsets, where Tv is the voice signal transmission slot, Te is the simultaneous call termination signal transmission slot, and Ts is the synchronization signal. R indicates a transmission slot, R indicates a reception slot, PTOFF indicates an OFF operation of the press talk switch 12, and PTON indicates an ON operation of the press talk switch 12, respectively.

[Example of combining the functions of two-way handset-to-handset direct communication and one-way handset-to-handset simultaneous call] FIG. This figure shows the configuration of an example of a digital cordless telephone device that has both simultaneous call (hereinafter referred to as simple call) functions. In this example, a press talk switch 12 is provided for the communication control unit 7, and a selection switch 13 between duplex and simplex is also provided. In this case, the press-to-talk switch 12 is configured to be effective only when simple communication is selected, as is clear from the figure.

When duplex communication is selected by the selection switch 13, the communication control unit 7 operates as shown in the block diagram of FIG. 1, and performs communication according to the communication procedure shown in FIG. A two-way direct conversation is made between the two handsets. Further, when simple communication is selected by the selection switch 13, the communication control unit 7 operates as shown in FIG. 9, and according to the operating procedure shown in FIG.
Depending on whether the press-talk switch 12 is turned on or off, a one-way call is made from one handset to all other handsets.

[0079] When the selection switch 13 is in a state where neither duplex nor simplex is selected, the handset operates in the same manner as before, and calls between handsets can be made via the base unit. .

[0080]

As explained above, according to the present invention, it is possible to directly communicate between handsets without relaying through the base unit. Therefore, it is possible to simplify the configuration of the parent device. Furthermore, since a single frequency is sufficient for transmitting and receiving calls, the efficiency of frequency use is high. Further, since only one pair of transmission slot and reception slot is required, this direct communication between handsets does not reduce opportunities for other handsets to make outside line calls, internal calls, or direct calls between handsets.

Further, according to the present invention, there is no need to relay the base unit, so even when the base unit and another slave unit are communicating, direct communication between another set of slave units is possible.

[0082] Direct communication between slave units is also possible even in locations where radio waves from the base unit cannot reach.

Furthermore, by using a one-way simultaneous call using a voice output control means such as a press talk switch, direct calls can be made between three or more slave units.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of essential parts of the present invention.

FIG. 2 is a diagram showing an overview of an embodiment of direct communication between two-way handsets according to the present invention.

FIG. 3 is a diagram showing the relationship between transmission and reception slots in the example of FIG. 2;

FIG. 4 is a block diagram of an example of the configuration of a slave device in the example of FIG. 2;

FIG. 5 is a diagram showing an example of a signal format of a command signal.

FIG. 6 is a diagram showing an example of a communication procedure for direct communication between two-way handsets according to the present invention.

FIG. 7 is a diagram showing an outline of an embodiment of a one-way direct simultaneous call between handsets according to the present invention.

FIG. 8 is a block diagram of an example of the configuration of a slave unit in the example of FIG. 7;

FIG. 9 is a block diagram of an embodiment of the main part of the example of FIG. 8;

FIG. 10 is a diagram showing an example of a communication procedure for a one-way direct call between slave units according to the present invention.

FIG. 11 is a diagram showing the relationship between transmission and reception slots in the example of FIG. 7;

FIG. 12 is a block diagram of an embodiment of the configuration of a handset having both a function of two-way direct communication between handsets and a function of unidirectional direct calls between handsets according to the present invention.

FIG. 13 is a diagram showing the relationship between transmission and reception slots of the TDD system and the TDMA/TDD system.

FIG. 14 is a diagram illustrating an outline of a conventional call between handsets in the TDD system.

FIG. 15 is a diagram illustrating the relationship between transmission and reception slots in the case of a conventional call between handsets using the TDD system.

FIG. 16 is a diagram illustrating an outline of a conventional telephone call between handsets using the TDMA/TDD system.

FIG. 17 is a diagram showing the relationship between transmission and reception slots in the case of a conventional call between handsets using the TDMA/TDD system.

[Explanation of symbols]

1 Transmitting/receiving antenna 3 Receiving section 5 Transmitting section 7 Communication control section 11 Key input operation section 12 Press talk switch 13 Duplex and simplex selection switch 20 Call detection means 21 for direct communication between two-way slave units
Partner handset number detection means 22, 31 Free channel acquisition means 23 Two-way handset direct connection request signal forming means 24, 34 Encoding means 25, 35 Radio control means 26, 36 Decoding means 27 Direct connection permission signal formation between handsets Means 28, 33
Synchronous signal forming means 30 Call detection means 32 for direct simultaneous calls between one-way slave units
Direct simultaneous connection request signal forming means 37 between slave units ON/OFF detection means BS of press talk switch 12 Base unit (base station)

Claims (3)

[Claims] Claim 1: In a digital cordless telephone device that consists of a base unit and a plurality of handsets and performs calls by making transmission and reception at different times, each handset is capable of two-way direct communication between the handsets. When making a call, means for capturing an empty communication channel, and means for transmitting a direct connection request signal between handsets to the other handset, including at least information indicating the captured empty channel and identification information of the other handset. and when receiving a direct connection request signal between the slave units from another slave unit,
A determining means for determining whether or not a call channel specified by the information indicating an unoccupied channel included in the direct connection request signal between handsets is an unoccupied channel; , means for sending a direct connection permission signal between handsets to the handset that has sent the direct connection request signal between handsets, and setting a transmission period and a reception period when receiving the direct connection permission signal between handsets; This digital cordless telephone device is equipped with a means for transmitting a synchronization signal to enable handsets to directly communicate with each other in two-way communication. Claim 2: In a digital cordless telephone device comprising a base unit and a plurality of handsets and making a call by making transmission and reception at different times, each handset has an audio output control operation means and a single handset. When making a direct simultaneous call between handsets, means for capturing an empty communication channel, and transmitting a direct simultaneous connection request signal between handsets to other handsets, including at least information indicating the captured empty channel. means for transmitting the direct simultaneous connection request signal between the slave units to other slave units, and means for transmitting a synchronization signal for transmission and reception; and means for receiving the direct simultaneous connection request signal between the slave units; a means for setting a communication channel set based on the information of an empty channel included in this signal; a means for receiving the synchronization signal and synchronizing transmission and reception; and after sending the synchronization signal for transmission and reception, means for detecting an audio outputting operation of the audio outputting control operating means and transmitting an audio signal to another handset via the captured communication channel; means for transmitting a one-way call termination signal between two handsets to other handsets via a channel, and a voice transmission control operation means for directly transmitting a one-way call from one handset to another handset. A digital cordless telephone device that is operated by operation. 3. Means for performing a direct call between two-way handsets according to claim 1; and means for performing a direct simultaneous call between handsets in a unidirectional manner from one handset to another handset according to claim 2. A digital cordless telephone device with