JP2563179B2 - Cordless phone - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cordless telephone.

(Prior art) A transmission from a slave unit reaches a base unit wirelessly via a base unit connected to a telephone line, and is transmitted from the base unit to a destination via a telephone line, and from the destination. A cordless telephone has already been proposed by the present applicant, which enables the operator of the slave unit to talk with the other party via the telephone line by outputting the transmission of the message from a speaker connected to the master unit. In the above cordless telephone, the antenna connected to the base unit and the external speaker are configured by one.

(Problems to be solved by the invention) Therefore, when the person carrying the child device is away from the speaker and the antenna of the parent device, it is not possible to make a satisfactory call.

(Means for Solving Problems) The cordless telephone of the present invention has the following configuration in order to solve the above-mentioned drawbacks.

In a cordless telephone consisting of a master unit connected to a telephone line and a slave unit that wirelessly transmits signals to the master unit, connecting a speaker to the master unit and receiving radio waves from the slave unit By connecting an external device equipped with an antenna and a demodulator that demodulates the radio waves received by the antenna and an S / N detector to multiple masters, a cordless phone that expands the communication range so that the slaves can talk to the master Telephone.

(Embodiment) FIG. 1 is a block diagram of a cordless telephone master unit and an external device according to an embodiment of the present invention, FIG. 2 is a schematic diagram of FIG. 1, and FIG. 3 is an embodiment of the present invention. It is a block diagram of a cordless telephone handset. FIG. 4 is a signal waveform diagram of the cordless telephone, FIG. 5 is a control flow chart of the master unit control unit, and FIG.
The figure is an external view of a cordless telephone. FIG. 7 is a waveform diagram of data generated in the handset, and FIG. 8 is a block diagram of a cordless telephone as another embodiment.

1 is a child device, 2 is a parent device, 3 (3a, 3b, 3c) is an external speaker, 4 (4a, 4b, 4c) is an external device, 5 is a telephone line, 6 is a power cord, 7 is a power supply, 15 is Battery, 16 is a charging terminal, 17 is a pilot signal generating unit for generating a 6 KHz signal in the embodiment, 25 is a communication circuit, 26, 27 and 28 are voice switches, 29 is a control unit, 40 is a demodulation unit, and 50 is S. The / N detector, 53 is a controller. 6
1 is a connecting line for connecting the master unit 2 and the external speaker 3, 62 to 67
Is a connection line that connects the master device 2 and the external device 4.

The external speaker 3 and the external device 4 according to the present invention may be integrated or separated. The external device 4 and the external speaker 3 are placed in a place where the mobile device 1 may be carried. In this embodiment, three external devices 4 are used,
A case where three external speakers 3 are connected to the master device 2 will be described.

First, in response to a bell signal (call signal) from the telephone line 5,
The operation in which the slave 1 responds via the master 2 to enter the talking state and the operation to enter the call termination state will be described.

When the bell signal from the telephone line 5 arrives at the base unit 2, the sounder 32 connected to the telephone line 5 sounds. In order for a person who has heard this ringing tone to respond with the handset 1, the operation unit of the handset 1
Press the start button at 19. When this start operation is performed, power is supplied from the battery 15 to each unit, and the pilot signal generated by the pilot signal generation unit 17 and shown in FIG. The control unit 12 sends the pilot signal to the input data unit 18 after a certain time (500 ms in the embodiment).
Based on the start data shown in FIG. 4 (b) output from the above, the transmission is interrupted as shown in FIG. 4 (c).
Is modulated by and is emitted as a radio wave from the antenna 14. This radio wave is received by the receiving unit 42 via the antenna 41 of the external device 4 and demodulated by the demodulating unit 40. The demodulated signal becomes start data in the pilot signal detection unit 52 and is output to the control unit 53.

On the other hand, the output from the second intermediate frequency amplifier 48 in the demodulation unit 40 is input to the squelch circuit 49. This squelch circuit inputs the output thereof to the control circuit 53 if there is a predetermined or more input. Only the external device 4a installed closest to the place where the handset 1 existed in response to the incoming call response of the handset 1 has its control unit.
Input from squelch 49 to 53 and pilot signal detector 52
It is assumed that the start data is input and that one or both signals are not input to the control unit 53 of each of the other external devices 4b and 4c. The control unit 53 of the external device 4 connects the AND output of both signals to the connecting line 6
It is sent to the control unit 29 of the base unit 2 via 5. The control unit 29 constantly monitors the connection lines 65, 66, 67, but detects that data is input only from the connection line 65. When the control unit 29 determines that the input data is start data, it activates the relay L and turns on the voice switch 26 corresponding to the external device 4. The contact 1 is switched by the operation of the relay L, and the telephone line 5 is captured by the communication circuit 25. Therefore, the audio signal from the handset 1 is transmitted to the telephone line 5 through the following route.

Microphone 11 of cordless handset 1-Amplifier 20-Transmission unit 13 (modulation) -Antenna 14- (Radio waves) -Antenna 41 of external device 4-Reception unit
42-demodulation unit 40-amplification unit 58-main unit voice switch 26-hook switch 24-communication circuit 25-contact l-telephone line 5.

On the other hand, the voice signal from the telephone line 5 is transmitted to the external speaker 3 through the following route.

Telephone line 5-contact l-call circuit 25-hook switch 23
-Amplifier 22-Connection line 61-External speaker 3.

As described above, the operator of the handset 1 transmits a call through the microphone 11 of the handset 1 and receives a call through the external speaker 3 through the telephone line 5.
You can talk to the other party via.

In the slave unit 1, the pilot signal generator 17 operates continuously after the start button is pressed, and the pilot signal is constantly transmitted by the transmitter.
It is modulated at 13 and sent to the master unit 2. When the slave unit 1 has a microphone input, a voice signal is transmitted together with the pilot signal.
The data is modulated together at 13 and sent to the external device 4.

The external device 4a receiving this radio wave detects the intermediate frequency output from the demodulation unit 40 by the squelch circuit 49 and sends the detection output to the control unit 53. Further, the pilot signal detected by the pilot signal detecting section 52 is sent to the control section 53. The control unit 53 sends the AND output corresponding to the input or the output of the coder 57 to the parent device 2.

The control unit 29 of the parent device 2 performs control corresponding to the input as shown in Table 1. The above-described state leading to the call is a result of performing the control a through the control c in the first table. That is, the hold circuit
After the initial state in which 30 is opened, control for maintaining the telephone line 5 in the talking state is performed.

When the call ends, the operator of the slave unit 1 presses the end button of the operation unit 19. When the end button is pressed, the control unit 12 receives the end data from the input data unit 18, intermittently transmits a pilot signal based on the end data, and transmits the pilot signal to the transmission unit 13. Further, this signal is emitted as a radio wave from the antenna 14 modulated by the transmitter 13.

This radio wave is received by the receiving unit 42 via the antenna 41 of the external device 4 and demodulated by the demodulating unit 40. The demodulated signal is detected by the pilot signal detection unit 52 and becomes data, and the control unit
Output to 53. The control unit 53 sends an AND output of the output of the squelch circuit 49 and the data to the master unit 2.

The control unit 29 of the master unit determines that this data is the call end data and controls the relay L to be restored. Relay L
Is restored, the contact 1 is disconnected, the telephone line 5 is opened, and the voice switch 26 is made non-conductive.

As described above, parent device 2 is in a state of waiting for an incoming call from telephone line 5 and a call from the child device.

The demodulation unit 40 of the external device 4 described above is the first station
Mixing section, first intermediate amplifier, second local oscillator, second mixing section, second
Since the demodulation unit is composed of the intermediate frequency amplifier and the detector 51 and is well known in the art, the description thereof will be omitted. Also S /
The N detection section 50 outputs a squelch output when the second intermediate frequency 455 KHz is higher than a predetermined value, and a squelch circuit 49 and a detector 51.
And a pilot signal detecting section 52 which outputs a detection output when the output of the above-mentioned includes a pilot signal.

The handset 1 goes out of the radio coverage area during a call,
If there is a voltage drop of 15 or if interference of radio waves is received, the external device 4 cannot receive the pilot signal and the squelch output. Control unit of external device 4
The 53 changes the output to the master unit from the AND output “HH” to the output of the coder 57, “LL”. The control unit 29 of the parent device 2 performs the operation of control b shown in Table 1. That is, the hold circuit 30 is operated to keep the telephone line 5 in a hold state and to send a hold sound to the telephone line 5. The handset operator knows that the external speaker 3 has disabled the call, and moves a little toward the external device 4a to try the call, or moves to the base unit 2 and talks with the handset 21 of the base unit. Intermittently. Remote unit is an external device
The control unit 53 of the external device 4a receives both the squelch output and the pilot signal to the master unit 2 when the slave unit 1 enters the coverage area of the radio wave when approaching 4a, or when the interference of radio waves stops as time passes. AND output of both, ie "HH"
Send output. The control unit 29 of the master unit performs the control c shown in Table 1. That is, the holding circuit 30 is opened and the telephone line 5
To call.

Next, when the operator of the slave unit 1 is talking with the other party via the telephone line 5 or is in a talking state as described above but is on hold, the handset 21 of the master unit 2 is raised by itself. Or when calling another person and raising the handset 21 of the base unit 2,
The hook switches 23, 24, 31 of the parent device 2 operate. When the hook switches 23, 24, 31 are operated, the external device 4a and the external speaker 3 are disconnected from the call circuit 25, and the handset 21 becomes the call circuit.
The telephone line 5 is connected via 25, and the handset 21 becomes ready for a call.

When the handset 21 is hung after the call, the contacts 23, 24, 31 of the hook switch return to their original positions. At this time, if the relay L is not operated and the contact l is opened, the telephone line 5 is opened. However, if the relay L operates and the contact 1 is closed, the slave unit 1 is brought into a communication state again with the telephone line 5 via the external device 4a and the master unit 2.

When the cordless handset 1 is in a call state with the telephone line 5 via the parent unit 2, when the external device 4a cannot receive both the pilot signal and the squelch output from the cordless handset 1, the telephone line 5 is put on hold for a certain period of time. To do. However, in order to improve the function, when the operator of the slave unit 1 wants to suspend the operation at his own convenience, the pilot signal is stopped and only the carrier is transmitted. When the external device 4a receives only this carrier wave, the control unit 53 changes the output to the base unit 2 from "HH" to "HL". The control unit 29 of the parent device 2 performs the control d shown in Table 1 here. That is, the control unit 29
Activates the hold circuit 30 to put the telephone line 5 in the hold state.

When the external device 4a receives only the above-mentioned carrier wave and inputs a pilot signal as a call resumption request from the slave, the control unit 53 changes the output to the master 2 from "HL" to "HH".
Upon receiving this signal, the control unit 53 of the parent device 2 performs the control e shown in Table 1. That is, the control unit 29 opens the holding circuit 30 and returns the telephone line 5 and the handset 1 to the call state. However, after the pilot signal transmission from the slave unit 1 is stopped, the output of the control unit 53 to the master unit changes from "HL" to "HH" when the transmission of the carrier wave is also stopped after a while. Upon receiving this signal, the control unit 29 of the master unit performs the control f shown in Table 1. That is, the control unit 29 disables the relay L.

When the relay L becomes inactive, the contact 1 becomes inactive and the telephone line 5 is opened. Thereafter, the cordless telephone base unit 2 returns to a state of waiting for an incoming call and a call from the handset 1.

In response to the above-mentioned incoming call response, the external device 4
5 shows a case where only the control unit 53 of the external device 4a inputs both the pilot signal output and the squelch output, but the control unit 53 of the other external device 4b also inputs both the pilot signal output and the squelch output. It will be described below.

The control unit 53 of the external device 4b sends the start data to the master device 2 similarly to the external device 4a. When the control unit 29 of the parent device 2 receives the same input in advance, the priority order is set. As an example, the priority is set to the external devices 4a, 4b, 4c. As shown in FIG. 5, the control unit 29 detects start data from the external devices 4a, 4b, 4c in this order. When the start data from the external device 4a is detected first, the control unit 29 causes the immediate voice switch 26
To conduct.

If the start data from the external device 4b is first detected, the external switch 4a having a higher priority is detected again, and if the start data can be detected, the voice switch 26 is turned on. If not, the voice switch 27 is turned on. The subsequent operation is the same as the above-mentioned incoming operation, and therefore its explanation is omitted.

The call receiving operation using FIG. 1 has been described above. In FIG. 1, the three external speakers 3 are designed to ring all at once, but in FIG. 8, the three external speakers are the voice switches 76, 77, respectively.
It is connected to the call circuit 25 of the base unit via 78 etc. These voice switches 76, 77, 78 are used as voice switches 26, 27, 28 and control unit.
If the external device 4a operates to output sound to the master unit by operating in conjunction with 29, the voice switch 26 and the voice switch 76 operate and the sound from the master unit is output from the external speaker 3
Sent from. Similarly, the external speaker 3b operates when the external device 4a is operating, and the external speaker 3c operates when the external device 4c is operating.

Next, when the start data is sent from the handset 1, it is possible to add the data for selecting an external speaker to the start data and send it to the external device 4 to specify the external speaker to be operated. External speaker 3 following the start data in Fig. 7
Shows the selection data. (A), (b), and (c) are data for selecting each of the external speakers 3a, 3b, 3c. Therefore, at the time of answering an incoming call, when the data of FIG. 7A is transmitted from the handset 1, this data is transmitted from any of the external devices 4 to the control unit 29 of the base unit 2. The control unit 29 makes the voice switch 76 conductive by the above-mentioned control by the start data and the subsequent selection data of the external speaker 3. Therefore, the voice from the telephone line 5 passes through the call circuit 25, the voice switch 76, etc. and is emitted from the external speaker 3a. Since any external device 4 may operate to operate the external speaker 3a, the external device 4 and the external speaker 3 can be operated independently.

Next, a case where a call is transmitted from the handset 1 to the telephone line 5 will be described.

When the start button of the cordless handset 1 is pressed as in the line capturing operation at the time of incoming call, the pilot signal is intermittently changed after a certain time by the start data of the input data section 18, modulated and further emitted from the cordless handset as a radio wave. . Control unit in the external device 4
The device to which both the pilot signal output and the squelch output are input to 53 receives this radio wave and outputs demodulated start data to the master unit 2.

When there is an input from the external device 4, the control unit 29 of the parent device turns on the corresponding voice switch based on the flowchart of FIG. As an example, when there is an input from the external device 4a, the audio switch 26 becomes conductive. Furthermore, the control unit 29 continues to detect data from the connecting line 65.

When the control unit 29 of the parent machine recognizes that the data is start data and operates the relay L, the contact l thereof is switched.

 The base unit 2 captures the telephone line 5 by the operation of the contact 1.

When the telephone line 5 is captured, a dial tone from the telephone line 5 is emitted from the external speaker 3. After hearing the dial tone, the operator of the child device 1 dials the telephone number of the call destination using the operation unit 19. The pilot signal is intermittently transmitted by the dial signal, and further modulated by the transmission unit 13 and emitted from the antenna 14 as a radio wave. Since the input to the control unit 53 of the external device 4a is a constant squelch output and an intermittent signal of the dial signal, the intermittent signal is directly input to the control unit 29 of the master unit 2.

The control unit 53 includes a delay circuit 55 so that the AND circuits 56A and 56B are operated by the dial pulse.

The control unit 29 of the base unit 2 discriminates the dial signal and operates the dial relay DL. The telephone line 5 is activated when the contact dl of the dial relay DL inserted in the call circuit 25 is interrupted.
Send a dial signal to. The central office 2 is connected to the other party via the telephone line 5 by the central office exchange (not shown) which has received the dial signal, and enters a communication state. Subsequent operations are the same as those described above, and will not be described.

It is also possible to select an external device that maximizes the following S / N ratio. In the above-described embodiment, the output of the S / N detector 50 is the binary output of H (high) and L (low) output from the squelch circuit 49, and the pilot signal detector 52.
It was a binary output of H and L output from.

This is detected by the detector 51 for the output from the squelch circuit 49.
The analog output has a level corresponding to the S / N ratio of the output from. Next, when there is a squelch output from the squelch circuit 49, the control unit 53 converts this analog output into a digital signal and sends it to the master unit 2. The control unit 29 of the parent device 2 compares the digital signals sent from the external devices 4 and operates the voice switch corresponding to the external device 4 having a high S / N ratio. As described above, the functions of the parent device and the external device 4 are improved and the child device 1
And the base unit 2 are in the best call state.

Further, as a simple switching method of the external device 4, a manual switch is simply provided in the external device instead of the voice switch provided in the master device, and when the slave device carrier responds or makes a call, the manual switch is operated. You may With this manual switch, an external device that mediates between the child device and the parent device can be selected.

In the embodiment, the cordless handset 1 generates a signal for intermittently modulating the start signal, the end data, and the like with the pilot signal, but two signals may be used instead of the intermittent pilot signal, or a multi-frequency signal may be used. You may use it.

In the embodiment, the dial signal to be transmitted to the telephone line is a pulse, but a simple circuit change is possible even when the dial signal is a PB signal.

The present invention can also be applied to a cordless telephone that wirelessly transmits and receives between a child device and a parent device. Others The present invention is not limited to the above embodiments.

(Effect) As described above, the present invention can bring an optimal communication state with the master unit regardless of where the carrier of the slave unit moves. The cordless telephone can be optimally used by the child carrier since the response or the calling is not restricted.

[Brief description of drawings]

FIG. 1 is a block diagram of a cordless telephone master unit and an external device according to one embodiment of the present invention, FIG. 2 is a schematic diagram of the cordless telephone master unit side of FIG. 1, and FIG. 3 is one embodiment of the present invention. It is a block diagram of an example cordless telephone handset. Fourth
The figure is a signal waveform diagram generated in the slave unit. FIG. 5 is a control flow chart for selecting an external device on the master unit, and FIG. 6 is an external view of the cordless telephone. FIG. 7 is a signal waveform diagram generated in the slave unit. FIG. 8 is a block diagram of a cordless telephone as another embodiment. 1 ... Slave unit, 2 ... Parent unit, 3 ... External speaker, 4 (4a, 4b, 4c) ... External device, 5 ... Telephone line, 40 ... Demodulation section, 50 ... S / N detection Department.

Continued Front Page (72) Inventor Hiroyuki Matsui 1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Minoru Shimizu, Examiner, Nippon Telegraph and Telephone Corporation Minoru (56) Reference JP-A-46-2753 (JP, A) Sho 53-98703 (JP, A) Actually opened Sho 61-70457 (JP, U)

Claims (4)

(57) [Claims] 1. A cordless telephone comprising a master unit connected to a telephone line and a slave unit wirelessly transmitting a signal to the master unit, wherein a speaker is connected to the master unit.
By connecting an external device equipped with an antenna that receives radio waves from the slave unit, a demodulation unit that demodulates the radio waves received by the antenna, and an S / N detection unit to multiple master units, the slave units can talk with the master unit. A cordless telephone with a wider call range. 2. An external device having a high S / N ratio of an S / N detection unit, of a plurality of external devices, is connected to a communication circuit of a master unit. Cordless phone as described. 3. When there are a plurality of external devices having the same S / N ratio of the S / N detector among the plurality of external devices, the external device having a higher priority is connected to the communication circuit of the master unit. The cordless telephone according to claim 1, characterized in that: 4. The cordless telephone according to claim 1, wherein one of a plurality of speakers connected to the master unit is selected by a control signal sent from the slave unit.