JP3036697B1 - Signal transmission method and apparatus in subscriber wireless device - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To increase the use efficiency of a communication channel and flexibly cope with different end-tones. SOLUTION: When a telephone B5 and a telephone A4 are in a call state,
When the telephone B5 hangs up the telephone and ends the call, the switch 1 transmits a call termination sound to the telephone A4. In the slave station 3, the end sound detection circuit 26 detects the end sound and gives the detection result to the control circuit 27. The control circuit 27 receives the termination sound detection signal and
25, and stores one cycle of the corresponding end voice from the time division multiplex extraction circuit 22. The switch 28 is operated at the time when the end sound for one cycle is stored, and the end sound input to the speech decoding circuit 23 is output from the time division multiplex extraction circuit 22 to the end sound stored in the storage circuit 25. , And the one-cycle end tone is repeatedly transmitted to the telephone A4. On the other hand, when the switch 28 is switched to the storage circuit 25 side, the slave station 3 instructs the master station 2 to open the communication path used for voice communication. The call path is opened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal transmission system in a subscriber radio apparatus having a time division multiplexed communication path.

[0002]

2. Description of the Related Art Conventionally, in a radio apparatus having a time-division multiplexed communication path, a communication path needs to transmit a signal transmitted from an exchange to a telephone connected to a slave station. Had to be secured until the handset of the telephone connected to the slave station was picked up. The time-division multiplexed communication path is normally connected to a subscriber whose capacity is equal to or greater than the capacity of the communication path, and the communication path is shared and used by several subscribers.

[0003]

For this reason, the shorter the talk time of a subscriber, the more opportunities for another subscriber to connect can be obtained. Therefore, means for improving the efficiency of use of the talk path is required.
In addition, the end call sound, the busy sound, and the like differ for each country, and may also differ depending on the connection status. If these sounds are prepared in advance in the slave station, the communication path can be opened and a pseudo sound can be sent out. Even when such sounds are prepared in advance in the slave station, it is very difficult to change the sound due to a change in the connection status.

In view of the above problems, an object of the present invention is to provide means capable of improving the use efficiency of a communication channel and flexibly coping with different end-tone sounds or busy sounds.

[0005]

SUMMARY OF THE INVENTION According to the present invention, in a communication path in a subscriber wireless system for transmitting a telephone line wirelessly, an output from an exchange is output when the other party ends the call or the other party is busy. Audible sound signal (end sound or call sound, etc.) having a predetermined periodicity, and stores the audible sound signal for one cycle in a storage circuit. The audible sound such as the end sound or call sound for one cycle is read out and repeatedly transmitted, and the use of the wireless communication path is improved by opening the communication path for other subscribers. Features.

That is, in a situation where a telephone exchange is established between a telephone exchange and a telephone via a master station and a child station by a time-division multiplexing method and wirelessly connected to a telephone line, for example, the other party talking to the telephone changes from the talking state. When the call ends, the switch sends a call end sound to the telephone. At this time, when the end sound is detected by the end sound detection circuit, one cycle of the end sound is stored in the storage circuit. Thereafter, the call termination sound stored in the storage circuit is read out, and the read call termination sound is transmitted to the telephone via the voice decoding circuit and the subscriber circuit.

Thus, before the telephone hangs up the handset,
It is possible to open the time-division multiplexed communication path,
In addition, since the call termination sound or call sound transmitted from the exchange is stored in the storage circuit and is reproduced, it is possible to flexibly cope with the frequency and transmission interval of the call termination sound or call sound. it can.

[0008]

FIG. 1 is a block diagram showing a first embodiment of the present invention, and shows a method of opening a communication channel at the time of a call termination. In this embodiment, an exchange 1, a subscriber circuit 11, a voice coding circuit 12, a time-division multiplexing circuit 1
3 and a base station 2 comprising a radio transmission / reception unit 14, a radio transmission / reception unit 21, a time division multiplex extraction circuit 22, a speech decoding circuit 2
3, subscriber circuit 24, storage circuit 25, call termination detection circuit 2
6. a slave station 3 including a control circuit 27 and a switch 28;
It is composed of a telephone A4 and a telephone B5.

First, the telephone A4 and the telephone B5 enter a talking state via the exchange 1 in response to a call from the telephone A4 or the telephone B5. At this time, the communication voice forms a communication path using a certain communication path by the time division multiplexing circuit 13 of the master station 2. Thereafter, when the call of the other party connected to the exchange 1 ends, the exchange 1 sends out a call termination sound.

[0010] The call termination sound output from the exchange 1 is input to the subscriber circuit 11 of the master station 2 and is encoded by the voice encoding circuit 12. After that, the audio signal encoded by the time division multiplexing circuit 13 is time division multiplexed, and
The signal is converted into a radio signal by the base station 4 and transmitted to the slave station 3.

In the slave station 3, a radio signal is received by the radio transmission / reception unit 21 and input to the time division multiplex extraction circuit 22. The time-division multiplexing / extracting circuit 22 extracts a portion of the communication channel on which the final call is multiplexed, and outputs the extracted portion to the voice decoding circuit 23. The voice decoding circuit 23 returns the coded end call sound to an audible sound signal again, and sends it out to the telephone A4 via the subscriber circuit 24. At this time, the time-division multiplexed communication path is normally occupied as it is until the telephone A4 hangs up the receiver or performs a call termination operation.

Therefore, according to the present invention, the termination sound is stored in the storage circuit 25.
The telephone A4 opens the communication channel even when the telephone set is not put on the receiver, and reads out and transmits the end call tone stored in the storage circuit 25 to the telephone A4. Normally, since the end sound is a repetition of an intermittent sound of a signal having a certain frequency component, if the end sound is stored in the storage circuit 25 for at least one cycle, it is repeatedly read out and output, thereby setting the telephone A4. Can be continued until the handset is placed.

As a procedure for storing, the call termination detecting circuit 2
The extracted timing is passed to the control circuit 27, the storage circuit 25 is controlled, and the one-cycle sound input from the output signal of the time-division multiplex extraction circuit 22, for example, one cycle thereof is stored in the storage circuit 25. Remember. After that, the switch 28 is operated according to the instruction of the control circuit 27.

The switch 28 switches the input system from the time-division multiplexing / extraction circuit 22 to the storage circuit 25 in accordance with a control signal from the control circuit 27.
3, the signal is decoded, and the telephone A
Then, a call termination sound is transmitted to the terminal 4. At this time, the time-division multiplexed communication path occupied by the telephone A4 is released, and can be used by another subscriber.

Next, the operation of this embodiment will be described with reference to FIG.
This will be described with reference to FIG. When the telephone B5 connected to the exchange 1 performs an operation of making a call to the telephone 4A (FIG. 2A), a call signal is sent from the exchange 1 to the subscriber circuit 11 of the master station 2, and the signal is transmitted. The master station 2 that has detected sends an incoming call signal to the slave station 3. Slave station 3
Upon receiving the incoming call signal, the telephone sends a ringing tone to the telephone 4A. When the bell of the telephone A4 rings and the telephone A4 is picked up, the telephone B5 and the telephone A4 enter a talking state (FIGS. 2-B and C).

Thereafter, when the receiver is placed on the telephone B5 to start the call termination operation (FIG. 2-D), the switch 1 transmits a termination sound to the telephone A4 (FIG. 2-E). At this time, in the slave station 3, the termination sound detection circuit 26 detects the termination sound based on the frequency and level of the termination sound, and gives the detection result to the control circuit 27 (FIG. 2F). The control circuit 27 operates the storage circuit 25 in response to the end sound detection signal, and stores one cycle of the end sound from the time division multiplex extraction circuit 22. (FIG. 2-I).

The switch 28 is operated at the time point when the end speech for one cycle is stored, and the end speech input to the speech decoding circuit 23 is stored in the storage circuit 25 from the time division multiplex extraction circuit 22. The call is switched to the end call sound, and a pseudo end call sound is transmitted to the telephone A4 (FIG. 2-J, K). Although the output from the storage circuit is stored for only one cycle, the one-cycle end tone is repeatedly transmitted to the telephone A4.

On the other hand, when the switching unit 28 is switched to the storage circuit 25 side, the slave station 3 instructs the master station 2 to open the communication path used for voice communication. 2
The communication path is opened at (FIG. 2-L).

Therefore, even if the telephone A4 does not perform a call end operation such as putting down the receiver after the end of the call, the communication path between the telephone B5 and the telephone A4 is automatically opened. The subscriber can use it immediately, and the efficiency of using the wireless communication path can be improved.

FIG. 3 is a block diagram of a communication path opening system according to a second embodiment of the present invention. The present embodiment is different from the first embodiment in that the slave station 3 is provided with a busy sound detection circuit 29 in addition to the end sound detection circuit 26, and other configurations are similar to those of the first embodiment. This is the same as the first embodiment.

Next, the operation of the second embodiment will be described.
This will be described with reference to FIGS. When telephone A4 makes a call (FIG. 4-A), a call signal is transmitted to exchange 1.
When the telephone at the connection destination is busy, the telephone A4 hears a busy tone from the exchange 1 (FIG. 4-E).

However, normally, as long as the telephone A4 does not pick up the receiver, the communication path is kept as it is. Therefore, the busy tone detection circuit 29 detects the busy tone, outputs the detection result to the control circuit 27, stores one cycle of the busy tone (FIG. 4-I), and stores the pseudo tone. The switch 28 is controlled as a middle tone and sent to the telephone A4. After that, an instruction to open the communication channel is issued to the master station 2 and the master station 2
Opens this communication path and makes the communication path available for other subscribers to use the communication path effectively.

In the above-described embodiment, the effective use of the communication path is achieved by automatically opening the communication path when the end call sound or the busy sound is detected. In the case of a communication path having a scene where a signal is transmitted, the method can be applied to open the communication path after transmitting a signal for one cycle through the communication path and to effectively utilize the communication path. .

[0024]

According to the present invention, the termination sound is stored, reproduced and transmitted, so that it is possible to easily cope with the case where the termination sound is different in each country. Therefore, it is possible to cope with a case where the call termination sound is different for each incoming and outgoing call.

Further, at the time of switching to the pseudo call termination sound, the used communication path is released and the other communication path can be used by other subscribers. Can be.

[Brief description of the drawings]

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

FIG. 2 is a sequence chart for explaining an operation of the first exemplary embodiment of the present invention.

FIG. 3 is a block diagram showing a second embodiment of the present invention.

FIG. 4 is a sequence chart for explaining an operation of the second exemplary embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 switch 2 master station 3 slave station 4, 5 telephone set 11, 24 subscriber circuit 12 voice coding circuit 13 time division multiplexing circuit 14, 21 wireless transmission / reception unit 22 time division multiplex extraction circuit 23 voice coding circuit 25 storage circuit 26 End call detection circuit 27 Control circuit 28 Switch 29 Busy sound detection circuit

Claims (4)

(57) [Claims] 1. A call termination sound output from an exchange when one of telephones connected to each other and busy performs a call termination operation on a communication path in a subscriber radio system for wirelessly transmitting a telephone line. Is detected, the call termination sound is stored for at least one cycle, then the wireless communication path is opened, and the stored call termination sound is read out and repeatedly transmitted to the other telephone at the connection destination. A signal transmission method in a subscriber wireless device, characterized in that: 2. A busy tone output from an exchange in response to a call signal from a telephone in a communication path in a subscriber wireless system for transmitting a telephone line wirelessly,
A subscriber radio apparatus characterized in that after storing at least one cycle of the busy tone, the wireless communication path is opened, and the stored busy tone is read out and repeatedly transmitted to a calling telephone. Signal transmission method. 3. A signal transmission apparatus in which an exchange and a telephone are connected via a master station and a slave station via a wireless communication path by a time division multiplexing method, wherein the slave station is connected to the slave station. A call termination detecting circuit for detecting a call termination tone transmitted from the exchange when the telephone at the other end of the telephone which is talking with the telephone goes from a talk state to a call termination state, and stores the call termination sound for at least one cycle A memory circuit that performs the operation of instructing the storage circuit to store the end sound when the end sound detection circuit detects the end sound and instructing the master station to open the wireless communication path. And a control circuit for reading out the call termination sound stored in the storage circuit and performing control to repeatedly send the call out to the telephone, wherein the master station releases the wireless communication path from the slave station. Open the wireless communication path in response to the instruction Signal transmission apparatus characterized by having means. 4. A signal transmission apparatus in which an exchange and a telephone are connected via a master station and a slave station via a wireless communication path by a time division multiplex method, wherein the slave station is connected to the slave station. A busy tone detection circuit that detects a busy tone output from the exchange in response to a call signal from the telephone; a storage circuit that stores the busy tone for at least one cycle; and the busy tone detection circuit When a busy tone is detected, the storage circuit is instructed to store the busy tone and the base station is instructed to open the wireless communication path, and the busy tone stored in the storage circuit is instructed. And a control circuit for performing a control of repeatedly sending the wireless communication path to the telephone, wherein the master station receives the instruction to open the wireless communication path from the slave station, and opens the wireless communication path. Signal transmission device characterized by having .