JP3738056B2 - Cordless phone - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multi-function digital cordless telephone apparatus such as a direct call between slave units in a parent-child telephone.
[0002]
[Prior art]
In recent years, PHS (Personal Handy phone System) is being put into practical use as a simple portable phone system.
The PHS employs a TDMA / TDD system in which a frame composed of 4 time slots for uplink and downlink is configured on a carrier for communication. Each carrier secures 4 channels (a set of uplink and downlink time slots). As the channel, a control channel used for control such as call setting and an information channel used for telephone call are used separately. Since the base station (base unit) and the slave unit perform wireless communication with relatively low power, the range of the wireless area is about a few hundred meters in radius. It is also possible to make a direct call between slave units that do not pass through (reference: “RCR STD-28” standard).
[0003]
[Problems to be solved by the invention]
However, according to the above-described prior art, there is a problem that even if an external line is received during a direct call between the slave units, the slave unit cannot receive the call. This is because the information channel and the control channel are different carriers, and the slave unit can use only one channel in the TDMA / TDD system.
[0004]
Further, if it is assumed that two channels are provided independently for the communication channels of the slave units, it will be possible to receive incoming calls even during a direct call between the slave units, but this causes a problem that the price of the product increases.
The present invention has been made in view of the above points, and it is an object of the present invention to provide a low-cost cordless telephone that enables an incoming call on an external line during a direct call between slave units.
[0005]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention of claim 1 is a child used for a parent-child telephone device comprising a parent device connected to a telephone line and a plurality of child devices, and performing parent-child communication and child-device direct communication. A receiving unit that is a cordless phone that is a functional cordless telephone and periodically switches the communication channel to a control channel to which control information is transmitted from the parent machine when communicating directly on the communication channel between the slave units; And interruption means for interrupting the direct call between the slave units when data indicating an incoming call to the own station is received from the control channel.
[0006]
According to a second aspect of the present invention, the receiving means includes a PLL circuit that generates a local oscillation frequency corresponding to one of a communication channel and a control channel, and a reception circuit that receives data on the channel corresponding to the local oscillation frequency. And during the direct communication between the slave units, a timing circuit that generates a pulse having a predetermined width for each period corresponding to the transmission period of the control channel, and a local oscillation frequency for the control channel at the pulse timing is designated to the PLL circuit, A channel switching circuit that switches a reception channel by designating a local oscillation frequency corresponding to a communication channel of direct communication between slave units to the PLL circuit at other timings.
[0007]
According to a third aspect of the present invention, the interruption means includes a transmission circuit that transmits disconnection data to a partner slave unit for direct communication between slave units when the external line incoming data is received, and the channel switching circuit includes: After the disconnection data is transmitted, the channel switching operation is stopped, and the frequency corresponding to the control channel is designated to the PLL circuit.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a block diagram showing a schematic configuration of the cordless telephone system of the present invention. This cordless telephone system includes a master unit 1 and slave units 2 to 4.
Base unit 1 is a TDMA / TDD base station having a function conforming to “RCR STD-28” and a function related to the present invention.
[0009]
First, the outline | summary of the said function of the main | base station 1 is demonstrated. The master unit is connected to a public network, a private extension network, etc., and is connected to a plurality of slave units that are located in the radio area of the master unit and registered for location using a control channel and an information channel. Call control and communication with the machine. Here, the location registration refers to registration for placing under the management of the parent device when data indicating the presence is received from the child device that has moved into the wireless area. The control channel is a channel used for call control such as outgoing / incoming calls. An information channel is a channel used for voice calls, data communications, and the like. Base unit 1 steadily performs intermittent transmission of synchronization information or the like in the control channel. For example, when receiving an incoming call from a foreign line to a slave unit, an information channel to be transferred to a voice call with a destination slave unit Is transmitted on the control channel, and then relaying such as a voice call is performed between the slave unit and the external line on the information channel.
[0010]
Next, functions related to the present invention of the base unit 1 will be described. When receiving the extension request data from the slave unit on the control channel, master unit 1 transmits the extension request data to the partner slave unit of the extension call.
Each of the slave units 2 to 4 has a function related to the present invention in addition to a function conforming to “RCR STD-28”.
[0011]
First, an outline of the above function of the slave unit will be described. Each slave unit is in a standby mode in which only the control channel that is constantly transmitted from the master unit is intermittently monitored, and in addition to the control channel monitoring, the home transceiver mode in which the information channel for 10 carriers is scanned and monitored. Have This standby mode is also referred to as a battery save mode because only control information called a superframe is intermittently received and the power consumption of the receiving circuit is significantly reduced compared to the home transceiver mode. The slave unit normally operates in the standby mode, and when calling another slave unit directly, the slave unit operates in the home transceiver mode and can directly start a call between the slave units without going through the master unit.
[0012]
Next, functions related to the present invention of each slave unit will be described. Each child device can call another child device via the parent device in addition to directly calling another child device in the home transceiver mode when starting an extension call. More specifically, when a direct call is started between slave units registered in the wireless area of the master unit, a direct call request between slave units is transmitted to the master unit via the control channel in the standby mode. Thereafter, the mode shifts to the home transceiver mode, and after receiving the call data from the other party of the extension call, the direct communication state between the slave units is entered. Furthermore, each handset can receive an incoming call even in a direct call state between handset units. Specifically, each slave unit receives an incoming incoming call by intermittently receiving the control channel during a call between the slave units in the information channel.
[0013]
FIG. 2 is a block diagram showing the configuration of base unit 1. As shown in the figure, the base unit 1 includes an antenna 18, a network circuit 3, an incoming call detection circuit 4, a speaker 5, an amplifier 6, a microphone 7, an amplifier 8, a receiving circuit 9, a transmitting circuit 10, a switching circuit 11, a speaker 12, and an input. The unit 13 and the control circuit 17 are included.
The network circuit 3 includes a connection circuit for connecting an external line such as a public network or a private branch exchange network, and a holding circuit, and is connected to a slave unit or a set of the speaker 5 and the microphone 7 via the switching circuit 11. .
[0014]
The incoming call detection circuit 4 detects an incoming call from an outside line.
The speaker 5 and the microphone 7 are hands-free speakers and microphones connected to the switching circuit 11 via the amplifier 6 and the amplifier 8, respectively.
The receiving circuit 9 receives a control channel carrier and an information channel carrier input from the antenna 18 and demodulates data on the carrier.
[0015]
The transmission circuit 10 modulates the data input from the switching circuit 11 onto the control channel carrier and the information channel carrier and transmits the modulated data from the antenna 18.
The switching circuit 11 connects either the combination of the reception circuit 9 and the transmission circuit 10 or the combination of the amplifier 6 and the amplifier 8 to the network circuit 3.
The input unit 13 includes a hold button 14, a numeric keypad 15, and an extension button 16, and receives a user operation instruction.
[0016]
The control circuit 17 is composed of a microprocessor and controls each circuit in order to realize a function as a master unit. For example, control information such as information for synchronization with respect to the slave unit is steadily generated and transmitted on the control channel via the transmission circuit 10, and information transmitted and received between the slave unit and the reception circuit 9 and the transmission circuit 10. Control is performed such that call data on the channel is relayed to an external line via the switching circuit 11 and the network circuit 3. Further, when the extension request data is input from the slave unit on the control channel received by the receiving circuit 9, the control circuit 17 generates the extension request data for the partner slave unit of the extension call designated by the data. Then, the data is transmitted via the transmission circuit 10.
[0017]
FIG. 3 is a block diagram showing the configuration of each slave unit. As shown in the figure, the slave unit includes an antenna 19, a PLL unit 20, a reception circuit 21, a speaker 22, an amplifier 23, a transmission circuit 24, an amplifier 25, a microphone 26, a codec 27, an input unit 28, an external line button 29, and an internal line button 30. , Keypad 31, hold button 32, bell 33, control circuit 34, timing instruction unit 34a, transmission / reception switching circuit 36, and channel switching circuit 37.
[0018]
The PLL unit 20 generates a local oscillation frequency signal corresponding to either the control channel or the information channel for the reception circuit 21 and the transmission circuit 24. The frequency of the local oscillation frequency signal is determined by setting a channel designation parameter by the channel switching circuit 37. The reception circuit 21 receives a control channel or an information channel corresponding to the local oscillation frequency from the PLL unit 20, and switches between transmission and reception. The time slot data at the timing designated by the circuit 36 is demodulated.
[0019]
The speaker 22 outputs data input from the receiving circuit 21 via the codec 27 and the amplifier 23 as an audio signal.
The transmission circuit 24 transmits the data from the control circuit 34 or the data from the codec 27 to the control channel corresponding to the local oscillation frequency from the PLL unit 20 in the time slot data at the timing designated by the transmission / reception switching circuit 36. Alternatively, the data is modulated from the information channel and transmitted through the antenna 19.
[0020]
The microphone 26 inputs the user's voice to the codec 27 via the amplifier 25.
The codec 27 decodes the voice-compressed data obtained from the receiving circuit 21, and compresses and encodes the voice input from the microphone 26 via the amplifier 25.
[0021]
The input unit 28 includes a hold button 14, a numeric keypad 15, and an extension button 16 and receives a user operation instruction.
The bell 33 is for incoming call notification.
The control circuit 34 is composed of a microprocessor and controls each circuit of the slave unit. For example, in the standby mode, the receiving circuit 21 controls the PLL unit 20, the transmission / reception switching circuit 36, and the channel switching circuit 37 so as to receive the control channel only for 5 mS (TDMA frame time) for each battery saving period. In the transceiver mode, the PLL circuit 20, the transmission / reception switching circuit 36, and the channel switching circuit 37 are controlled so that the reception circuit 21 sequentially receives the control channel and the information channel. In communication with the parent device or other child devices, the receiving circuit 21 and the transmitting circuit 24 are controlled to transmit and receive data of the codec 27 through the information channel. In particular, in the direct communication between the slave units, the receiving circuit 21 and the transmitting circuit 24 are controlled so as to transmit / receive data of the codec 27 through the information channel, and the receiving circuit 21 receives the control channel for 5 mS every battery saving period. Control as follows.
[0022]
Timing instructing unit 34a outputs a timing signal indicating a battery saving cycle in direct communication between slave units. The battery save period is assumed to be about 1 second in this embodiment.
The transmission / reception switching circuit 36 turns on the operations of the reception circuit 21 and the transmission circuit 24 at the timing of the reception time slot and transmission time slot in the TDMA frame in communication with the parent device 1 or other child devices, respectively.
[0023]
The channel switching circuit 37 switches the reception channel in the reception circuit 21 from the information channel to the control channel for each period indicated by the timing signal from the timing instruction unit 34a during direct communication between the slave units. Specifically, for each period of the timing signal, parameter setting corresponding to the control channel is performed on the PLL unit 20, and parameter setting corresponding to the information channel is performed after 5 mS.
[0024]
Regarding the cordless telephone system in the embodiment of the present invention configured as described above, its operation is (1) standby, (2) transition to a direct call between slave units, and (3) an external line during a direct call between slave units The explanation will be divided into incoming operation and (4) hold operation during an outside line call.
(1) Standby operation.
Each of the slave units 2 to 4 is registered in the base unit 1 and is in a position where it can communicate with each other. Each slave unit is in a standby mode for receiving intermittently in synchronization with the superframe on the control channel from the master unit (FIG. 5).
(2) Shifting to direct calls between slave units.
[0025]
FIG. 4A shows a transmission / reception sequence diagram between a parent and a child representing a transition to a direct call between slave units and an external line incoming call in a direct call between slave units.
In FIG. 4A, when a direct call is performed between the slave units 2-3, the extension button 30 and the numeric keypad 31 indicating the slave unit 3 as the extension partner are pressed by the user. The extension mode instruction data (A) for instructing the extension call between the slave units 2-3 is transmitted from the control circuit 34 to the control channel via the transmission circuit 24 (FIG. 6).
[0026]
When the master unit 1 receives the extension mode instruction data (A), it transmits the inter-slave unit direct call instruction data (B) to the slave unit 3 on the control channel (FIG. 7).
When receiving the direct call instruction data (B) between the slave units, the slave unit 3 shifts to the channel for direct call between the slave units and sends the call response data (C) to the slave unit 2 at the same slot timing as the master unit. (FIG. 8). Thereby, the subunit | mobile_unit 2 and the subunit | mobile_unit 3 transfer to a direct call between subunit | mobile_units. After this transition, the slave unit 2 also receives a control channel from the master unit for each cycle of battery saving. However, while the control channel is received (5 mS), the voice data of the inter-slave device call is interrupted, but there is almost no effect in practical use.
(3) External line incoming call operation during direct call between slave units.
[0027]
In FIG. 4 (a), for example, when an external line incoming call is received from the master unit 1 to the slave unit 2 during a direct call between the slave units, the master unit 1 transmits simultaneous incoming data (D) (FIG. 9). Upon receiving this, the slave unit 2 transmits forced termination data (E) of the direct call between the slave units to the slave unit 3 and shifts to the standby mode. In addition, when the slave unit 3 receives the forced end data (E), the slave unit 3 shifts to a standby mode. Thereby, the subunit | mobile_unit 2 receives simultaneous call data in standby mode continuously, and alert | reports an incoming call to a user through the bell 33. FIG. Thereafter, in response to a response by the user operation (pressing the outside line button), the operation shifts to outside line connection.
(4) Hold operation during an external call.
[0028]
FIG. 4B shows a transmission / reception sequence diagram between a parent / child for holding an outside line call, shifting to a direct call between slave units, and releasing a hold.
FIG. 2B shows an operation in a case where an external line call is transferred to the handset 3 after the handset 2 has made an internal line call with the handset 3 during an external line call.
The extension unit 2 indicates that an extension call is made between the slave units 2-3 when the user presses the extension key 30 after the extension button 30 is pressed by the user and the numeric keypad 31 specifying the slave unit 3 is pressed. Instruction data (F), line hold start data (G), and hold release machine designation data (H) are transmitted on the call channel, and the mode shifts to the home transceiver mode (FIG. 10). Here, the hold cancellation device designation data (H) is data indicating which child device the parent device 1 should accept hold cancellation from. In this example, the child device 2 and the child device 3 are designated. To do.
[0029]
When the base unit 1 receives the data (F) to (H), it transmits response data (I) to the handset 2 and puts the line on hold (FIG. 11). At this time, the base unit 1 temporarily stores the slave units 2 and 3 designated by the hold release machine designation data (H) as the hold release machine. Further, base unit 1 transmits inter-slave unit direct call instruction data (J) between handset units 2-3 to handset units 2 to 4 (FIG. 12).
[0030]
When receiving the direct call instruction data (J) between the slave units, the slave unit 3 shifts to the home transceiver mode and transmits a response signal (K) to the master unit 1 (FIG. 13).
When the base unit 1 receives the response signal (K), the base unit 1 shifts to system hold with the handset units 2 and 3 as release units.
Further, direct communication between the slave units is started by the response signal (C) from the slave unit 3 to the slave unit 2 (FIG. 14). During this time, the base unit 1 accepts the hold release data from any of the handset units 2 and 3 but does not accept the data from the handset unit 4. For example, after the inter-slave unit direct call is terminated by the inter-slave unit disconnection instruction data (L) from the slave unit 3 to the slave unit 2, the hold release data (M) is notified from the slave unit 3 to the master unit 1 In this case, the base unit 1 releases the hold and transmits response data (N) to the handset 3 to connect the handset 3 to the outside line. Further, since the home transceiver mode is a maximum of 3 minutes, the parent device 1 shifts to a hold that can be released from any of the child devices 2 to 4 and the parent device 1 after 3 minutes.
[0031]
In the above embodiment, the timing for receiving the control channel during the direct call between the slave units is set for each battery saving cycle, but is not limited thereto. For example, the control channel and the information channel may be switched alternately for each TDMA frame only during a direct call between the slave units.
FIG. 16 is a block diagram showing the configuration of the slave unit in this case. The configuration is as shown in FIG. In FIG. 16, a codec 27a is a codec provided with a mode for compressing to 32 kbps and a mode for compressing to 16 kbps as a method for compressing and encoding audio data. Works with. This is because the information transfer rate of the information channel is reduced from the usual 32 kbps to substantially 16 kbps. The timing instruction unit 34b alternately performs parameter setting for designating the local oscillation frequency corresponding to the control channel and the information channel for the PLL unit 20 for each TDMA frame only during a direct call between the slave units.
[0032]
【The invention's effect】
As described above, according to the cordless telephone of the present invention, it is possible to receive an incoming incoming call via the master unit during a direct call between the slave units without increasing the price of the slave unit. effective.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of a cordless telephone system in an embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of a base unit 1 in the same embodiment.
FIG. 3 is a block diagram showing a configuration of each slave unit in the same embodiment.
FIG. 4A is a transmission / reception sequence diagram between a parent and a child representing the start of a direct call between slave units and an external line incoming call in the direct call between slave units in the same embodiment.
(B) It is the transmission-and-reception sequence diagram between the holding | maintenance of the outside line call in the same Example, the transfer to the direct call between slave units, and the cancellation | release of a hold | maintenance.
FIG. 5 is an operation explanatory diagram of the same embodiment.
FIG. 6 is an operation explanatory diagram of the same embodiment.
FIG. 7 is an operation explanatory diagram of the same embodiment.
FIG. 8 is an operation explanatory diagram of the same embodiment.
FIG. 9 is an explanatory diagram of operations in the embodiment.
FIG. 10 is an explanatory diagram of operations in the same embodiment.
FIG. 11 is an operation explanatory diagram of the same embodiment.
FIG. 12 is an explanatory diagram of operations in the same embodiment.
FIG. 13 is an explanatory diagram of operations in the same embodiment.
FIG. 14 is an explanatory diagram of operations in the embodiment.
FIG. 15 is an explanatory diagram of operations in the same embodiment.
FIG. 16 is a block diagram showing another configuration of base unit 1 in the same embodiment;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Main | base station 2 Sub-unit 2-4 Sub-unit 3 Network circuit 4 Incoming detection circuit 5 Speaker 6 Amplifier 7 Microphone 8 Amplifier 9 Reception circuit 10 Transmission circuit 11 Circuit 12 Speaker 13 Input part 14 Hold button 15 Numeric keypad 16 Extension button 17 Control circuit 18 antenna 19 antenna 20 PLL unit 21 receiving circuit 22 speaker 23 amplifier 24 transmitting circuit 25 amplifier 26 microphone 27 codec 27a codec 28 input unit 29 outside line button 30 extension button 31 numeric keypad 32 hold button 33 bell 34 control circuit 34a timing instruction unit 36 transmission / reception Switching circuit 37 Timing indicating circuit

Claims (3)

A cordless phone that is a slave unit used in a master-slave phone device that is composed of a master unit connected to a telephone line and a plurality of slave units, and that performs parent-child communication and direct communication between slave units,
When communicating directly on the communication channel between the slave units, the communication channel is switched to the control channel to which the control information from the master unit is transmitted periodically, and receiving means for receiving an external line addressed to the own station An interruption means for interrupting direct communication between the slave units when data is received from the control channel;
A cordless telephone characterized by comprising: The receiving means includes
A PLL circuit that generates a local oscillation frequency corresponding to any one of the communication channel and the control channel;
A receiving circuit for receiving data on a channel corresponding to the local oscillation frequency;
A timing circuit that generates a pulse having a predetermined width every cycle corresponding to the transmission cycle of the control channel during direct communication between the slave units;
Specify the local oscillation frequency for the control channel at the pulse timing in the PLL circuit, and switch the reception channel by specifying the local oscillation frequency corresponding to the communication channel for direct communication between slave units in the PLL circuit at other timings. The cordless telephone according to claim 1, further comprising a circuit. The interruption means includes a transmission circuit that transmits disconnection data to a partner slave unit for direct communication between slave units when the outside line incoming data is received,
The channel switching circuit to the cut data transmission, the channel switching is stopped, claim 2 cordless telephone according to the frequency corresponding to the control channel, wherein the Turkey specify the PLL circuit.

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