JP3066311B2 - Communication method and communication system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication method and a communication system, and more particularly to a communication method and a communication system capable of performing a call smoothly even if the call is interrupted or interrupted. .

[0002]

2. Description of the Related Art Conventionally, among mobile communication systems using automobiles and cellular phones, for example, in an automobile communication system, a plurality of radio base stations are arranged every several kilometers.
Area where each wireless base station can talk (service area)
Are formed. The radio network controller performs communication control between the mobile phone and the radio base station. For example, it checks which base station is closer to the mobile phone and determines which frequency is used.

[0003] The radio base station monitors the signal strength from the mobile phone to determine whether or not the mobile phone is within its service area. When the radio base station determines that the signal strength has decreased and the car telephone has gone out of the service area of its own, the radio base station notifies the radio network controller of the fact. The radio network controller analyzes the moving direction of the mobile phone based on the result of the determination and the signal strength of the mobile phone received from the peripheral base station, and determines a new base station to take over the ongoing communication. figure out. The radio network controller further notifies the mobile phone of the currently available channel number of the new base station, and instructs the new base station to start communication with the mobile phone. And the radio network controller,
The base station is switched so that a signal is supplied from the new base station to the communication partner. Thus, the tracking exchange in the vehicle communication system is performed.

In the above-mentioned automobile communication system,
In particular, to meet the large demand for communications in large cities,
It has been practiced to reduce the service area so that radio waves of the same frequency can be effectively reused at a sufficiently far away point.

[0005]

However, when the service area is reduced, the above-mentioned pursuit exchange is frequently performed, which not only complicates the processing, but also causes the moving speed of the vehicle to be lower than the speed of the pursuit exchange. If it is early, there is a problem that the call is interrupted on the way.

[0006] Regardless of the size of the service area,
When a car phone leaves the service area,
If a new base station is not found or radio waves do not reach the base station, the call will be interrupted halfway.
Further, there is a problem that the communication is interrupted or interrupted due to noise, other communication signals, fading and the like existing in the wireless section.

[0007] By interrupting the call in this way,
The user on the receiving side cannot sufficiently hear the contents of the conversation, and it becomes necessary to re-listen the contents of the conversation to the user on the transmitting side, so that a smooth conversation cannot be performed. The interruption or interruption of the above-mentioned call occurs not only in the automobile communication system but also in the mobile phone system and the simplified mobile phone system (PHS). It is important to take countermeasures for obtaining a good call. is there.

[0008] JP-A-5-191478 (H04M 1/0
0), when the level detection unit detects that the radio signal has dropped to a level at which communication between the master unit and the slave unit is impossible, the voice call by the slave unit is put on hold, and the holding tone generation unit gives a hold tone. Is transmitted to a communication partner via a base unit side voice communication unit. However, in this cordless telephone, the user on the transmitting side cannot perform transmission until the communication is resumed after a certain period of time elapses after the hold tone is transmitted to the other party, so that communication with the receiving side is not possible. There is a problem that a call cannot be made smoothly.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a wireless communication system and a wireless communication method capable of smoothly performing communication even when communication is interrupted. Is to do.

[0010]

In order to solve the above-mentioned problems, the invention according to claim 1 determines whether communication is possible by monitoring the state of a communication signal according to the communication content, and determines whether or not communication is possible. Based on the result of the determination, the communication contents during the period in which communication is determined to be unavailable are recorded, and then, when it is determined that communication is possible, the recorded communication contents are eliminated from the communication time delay caused by the communication inability period. In order to re-
The gist is a communication method to be generated.

[0011]

According to a second aspect of the present invention, there is provided a communication method for recording and reproducing communication contents at a first speed and transmitting a communication signal corresponding to the reproduced communication contents. By monitoring the state of the communication signal that has been transmitted, it is determined whether communication is possible, and based on the determination result, reproduction is stopped during the period in which communication is determined to be impossible, and only recording of communication contents is performed. At the time when it is determined that communication is possible, the recorded communication content is reproduced at a second speed higher than the first speed so as to eliminate a time delay of communication caused by a communication disabled period. The communication method is the gist.

[0013] invention as set forth in claim 3, in the communication method according to claim 2, after the communication content recorded is reproduced all in the incommunicable period, the first speed from the second speed In this case, the recording and reproduction of the communication contents are performed.

[0014] According to a fourth aspect of the present invention, it is determined whether or not communication is possible by transmitting means for transmitting a communication signal according to the contents of communication and monitoring the state of the communication signal transmitted by the transmitting means. Determining means, and a recording means for recording the communication content, based on a determination result of the determining means,
In order to record the communication contents during the period in which it is determined that communication is impossible, the recording means is controlled, and at the time when it is determined that communication is possible, the communication content recorded in the recording means is changed to the communication time caused by the communication disable period. specific delay is eliminated of
A gist is a communication system including a control unit for controlling the recording unit so as to perform high-speed reproduction so as to be reproduced .

[0015]

According to a fifth aspect of the present invention, the communication content is first.
Recording / reproducing means for recording / reproducing at a speed of
Transmitting means for transmitting a communication signal corresponding to the communication content reproduced by the reproducing means; determining means for determining whether communication is possible by monitoring a state of the communication signal transmitted by the transmitting means; Based on the result of the determination by the determination means, while controlling the recording and playback means to stop the reproduction and only record the communication content during the period determined that communication is impossible, at the time when it is determined that communication is possible, The communication content recorded in the recording / reproducing means, so that the communication time delay caused by the communication unavailable period is eliminated,
A gist of the present invention is a communication system including control means for controlling the recording / reproduction means so as to reproduce the data at a second speed higher than the first speed.

According to a sixth aspect of the present invention, in the communication system according to the fifth aspect , after the communication content recorded during the communication disabled period has been completely reproduced, the control means changes the second speed. Switching to the first speed,
The gist of the present invention is to control the recording / reproducing means in order to record / reproduce communication contents.

(Operation) According to the first and fourth aspects of the present invention, when it is determined that communication is possible, the recorded communication contents are reproduced at high speed in the communication disabled period.
It is. Therefore, even if the communication is interrupted and the call is interrupted, the missing part of the call that was temporarily lost due to the interruption is interpolated, and the receiving user can hear the missing part of the call quickly.
By doing so, it is possible to make a call smoothly.

[0019]

According to the second and fifth aspects of the present invention, when it is determined that communication is possible, the time delay of communication caused by the recorded communication content due to the communication disabled period is eliminated. Playback is performed at a second speed higher than the first speed.

According to the third and sixth aspects of the present invention, after all of the communication contents recorded during the communication disabled period are reproduced, the communication speed is switched from the second speed to the first speed to record the communication contents.・ Playback is performed. Therefore, the user on the receiving side can return to real-time communication and make a call after quickly listening to the missing part of all the call contents.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention embodied in an automobile communication system will be described below with reference to the drawings.
As shown in FIG. 1, an automobile communication system includes an automobile telephone terminal device (hereinafter, simply referred to as an automobile telephone) as a communication terminal device, a plurality of radio base stations (only one is shown), a radio channel control station 3, It is composed of a public telephone network 4 and a subscribed telephone terminal device (hereinafter simply referred to as a subscribed telephone) 5. Each radio base station 2 is arranged every several kilometers, and each covers an area where communication is possible (service area). The radio network controller 3 comprises the mobile phone 1 and the radio base station 2
For example, it checks which base station 2 is close to a car phone and determines which frequency (channel) to use.

The wireless base station 2 monitors the transmission signal intensity from the mobile phone 1 to determine whether the mobile phone 1 is within its service area. When the radio base station 2 determines that the transmission signal strength has decreased and the mobile phone 1 has gone out of the service area of its own, the radio base station 2 notifies the radio network controller 3 of the fact. The radio network controller 3 makes the peripheral base station monitor the transmission signal strength of the channel used by the mobile phone 1 based on the determination result, and receives the signal strength data therefrom. And
Based on the signal strength data from the neighboring base stations, the direction of movement of the mobile phone is analyzed to find a new base station to take over the ongoing communication.

If signal strength data cannot be received from any of the neighboring base stations, or if the received signal strength is extremely low due to factors such as noise, the radio network controller 3 sets a new base station. It cannot be found, and it is determined that a call is not possible (line condition is not good).
Then, the radio network controller 3 transmits the transmission disable signal TDS to the mobile phone 1 via the base station 2 based on the determination result.

After the transmission of the communication disable signal TDS, the signal strength data could be received from the peripheral base station before the predetermined time elapses, or the signal strength data already received reached the predetermined level. In this case, the radio network controller 3 determines that communication is possible and finds a new base station. Then, the radio network controller 3 transmits a transmission enable signal TES to the mobile phone 1 via the base station 2 based on the determination result.

When a new base station is found, the radio network controller 3 notifies the mobile phone 1 of the currently available channel number of the new base station, and notifies the new base station of the vehicle number. An instruction to start communication with the telephone 1 is issued. Then, the radio network controller 3 switches the base stations so that a signal is supplied from the new base station to the subscriber telephone 5 of the communication partner. In this way, the tracking exchange in the vehicle communication system is performed.

Next, the mobile phone 1 will be described. The mobile phone 1 has a radio circuit 11, a voice circuit 12, a memory 1
3, write address counter 14, read address counter 15, control circuit 16, microphone 17, and receiver 1
8 is provided. The audio circuit 12 includes a D / A converter 21 connected between the memory 13 and the wireless circuit 11, and an A / D converter 22 and a microphone amplifier 23 connected in series between the memory 13 and the microphone 17. And a receiver amplifier 24 connected between the radio circuit 11 and the receiver 18.

The radio circuit 11 includes a transmitting unit and a receiving unit (not shown), and the transmitting unit includes the D / A converter 2 of the audio circuit 12.
The analog audio signal output from 1 is modulated to generate a transmission signal, and the transmission signal is converted into an RF signal.
The receiving unit converts a received signal (RF signal) received via the antenna 10 into an IF (intermediate frequency) signal,
Demodulates the F signal to obtain an analog voice signal and transmission disable signal TD
S and a transmission enable signal TES are generated. The analog audio signal is output to the receiver amplifier 24 of the audio circuit 12,
The transmission disable signal TDS and the transmission enable signal TES are output to the control circuit 16.

The microphone amplifier 23 of the audio circuit 12 amplifies the level of the analog audio signal output from the microphone 17 during transmission, and the A / D converter 22 converts the amplified analog audio signal into a digital audio signal. Convert to This digital audio signal is FIFO (First In Firs
t Out) is stored in the memory 13, and the digital audio signals stored in this memory are read out in
/ A converter 21. The D / A converter 21 converts a digital audio signal into an analog audio signal and outputs the analog audio signal to the radio circuit 11. At the time of reception, the receiver amplifier 24 attenuates the level of the analog audio signal output from the wireless circuit 8 and outputs the signal to the receiver 18.

The write address counter 14 has an A / D
The write address of the digital audio signal written from the converter 22 to the memory 13 is counted, and the read address control unit 15 counts the read address of the digital audio signal read from the memory 13 to the D / A converter 21. In the present embodiment, during normal transmission,
The write address counter 14 and the read address counter 15 perform a counting operation so that an audio signal can be sent to the wireless circuit 11 without a time lag.

The control circuit 16 receives the transmission disable signal TDS and the transmission enable signal TES output from the radio circuit 11, and controls the operations of the write address counter 14 and the read address counter 15 based on these signals. . When the transmission disable signal TDS is input, the control circuit 16
Stops the counting operation of the read address counter 15 and starts recording the digital audio signal (sending contents) in the memory 13. At the same time, the count value of the read address counter 15 is initialized.

When the transmission enable signal TES is input before the predetermined time elapses after the input of the transmission disable signal TDS, the control circuit 16 starts the count operation of the read address counter 15 and causes the memory 13 to The recorded digital audio signal is reproduced using a speech speed conversion technique while shortening the time axis, and output to the D / A converter 21. That is,
The control circuit 16 switches the count speed of the read address counter 15 from the normal speed as the first speed to the fast listening speed as the second speed so that the read speed of the digital audio signal is faster than the write speed. Then, the control circuit 16 transmits the content currently being spoken at the point in time when all the transmission contents recorded in the memory 13 are output to the D / A converter 21 and the read address catches up with the write address. Then, the count speed is switched from the fast listening speed to the normal speed.

If the transmission enable signal TES is not input within a predetermined time after the input of the transmission disable signal TDS, the control circuit 16 converts the recorded digital audio signal into a high-speed signal using a speech speed conversion technique. , It is determined that the time delay caused by the transmission unavailable period cannot be eliminated. Then, the control circuit 16 clears the transmission content recorded in the memory 13 and starts the counting operation of the read address counter 15 at the normal speed.

Next, the operation of the mobile telephone communication system configured as described above will be described with reference to the flowchart shown in FIG. In step S1, when a call using the mobile phone 1 is started, the content spoken by the user is transmitted as it is. In step S2, the radio network controller 3
Determines whether the line condition is good or whether the tracing and exchange are performed well and the call is possible. If the call is possible, the process proceeds to step S1 to continue the call. Is done. As shown in FIG. 3, when the communication is disabled at time t1, a transmission disable signal TDS is input from the radio network controller 3 to the control circuit 16 via the base station 2 and the radio circuit 11. Then, in step S3, the control circuit 16
Stops the counter operation at the read address 15, and stops reading the audio signal, that is, stops transmitting. And
In step S4, the recording of the digital audio signal (sending contents) in the memory 13 starts, and at the same time, the count value of the read address counter 15 is initialized.

In step S5, after the transmission disable signal TDS is inputted, the line condition becomes good until a predetermined time elapses, or whether the call is made possible after the tracking exchange is performed. If it is determined that the call cannot be made, the process proceeds to step S4, and the recording of the transmitted content is continued. As shown in FIG. 3, when a telephone call becomes possible at time t2 within a predetermined time, a transmission enable signal TES is input from the radio network controller 3 to the control circuit 16 via the base station 2 and the radio circuit 11. Is done. Then, in step S6, the control circuit 16 starts the counter operation of the read address 15, and reproduces the transmission content 50 recorded in the memory 13 during the time t2 to t1 at high speed using the speech speed conversion technique. . That is, the count speed of the read address counter 15 is switched from the normal speed to the fast listening speed.

In step S7, all of the transmission contents recorded in the memory 13 are not reproduced and transmitted, and
If the read address has not caught up with the write address, the process proceeds to step S6 and the transmission of the transmission content is continued. If all the transmitted contents have been transmitted and the read address has caught up with the write address, in step S8, the count speed is switched from the fast listening speed to the normal speed in order to transmit the currently talked content. As a result, the transmission content 50 that has been lost due to the inability to transmit during the time t2 to t1 on the receiving side is transmitted to the subscriber telephone 5 while being temporally compressed. In this way, the user of the subscriber telephone 5 can quickly listen to the temporally compressed transmission content 51, so that even if the transmission content is interrupted,
It becomes possible to hear the contents.

In step S9, it is determined whether or not the line has been disconnected by the user's operation and the call has been terminated. If the call has not been terminated, the process proceeds to step S1 to execute the processing in each of the above-described steps. Is performed. If it is determined in step S5 that a call cannot be made and that the transmission enable signal TES has not been input after a predetermined time has elapsed from the input of the transmission disable signal TDS in step S10, the control proceeds to step S11. The circuit 16 clears the transmission contents recorded in the memory 13, that is, discards the transmission contents during the transmission disabled period, starts the reading operation of the read address counter 15 at the normal speed, and proceeds to step S9. .

As described in detail above, this embodiment has the following effects. (1) When the transmission becomes impossible, the transmission is stopped, the recording of the transmission contents is started in the memory 13, and when the transmission becomes possible, the transmission contents stored in the memory 13 are transmitted. High-speed playback was performed using the speed conversion technology. Therefore, the missing part of the transmission content lost due to the temporary interruption of the transmission is interpolated, and the user on the receiving side can hear the transmission content by quickly listening to the missing part, and as a result, Calls can be made smoothly. In addition, the user on the transmitting side can continue the transmission without noticing the fact that the transmission becomes impossible even if the transmission becomes impossible, and as a result, the call can be smoothly performed.

(2) The missing portion of the transmission content during the period in which the tracking exchange was not properly performed and the transmission was disabled was interpolated by the above-mentioned speech speed conversion technique. Therefore, as described in the related art, when the service area is reduced in order to effectively use the same frequency, even if the tracking exchange is performed frequently and the call is interrupted halfway, the user on the receiving side does not It is possible to listen to the contents of the transmission without losing the contents and make the call smoothly.

The present invention is not limited to the above embodiment, but may be implemented as follows. (B) The base station 2 detects whether the line condition is good by detecting the noise included in the transmission signal from the mobile phone 1 when the mobile phone 1 is within the service area of its own. Determine whether or not. And base station 2
Outputs a transmission disable signal TDS to the mobile phone 1 when the line state is not good and the transmission is not possible, and then outputs a transmission enable signal TES to the mobile phone 1 when the line state becomes good. You may make it.

(B) Instead of sending out the missing portion of the transmission content stored in the memory 13 at high speed by the speech speed conversion technique, control is performed so that the missing portion of the transmission content is thinned out from the memory 13 and transmitted. The circuit 15 may control the operation of the read address counter 15. In this case, the user on the receiving side intermittently listens to the missing part, so that the call can be smoothly performed.

(C) The present invention relates to a portable telephone system other than a car telephone communication system and a simplified portable telephone system (PH).
You may apply to S). (D) In the above embodiment, even during normal transmission,
The voice signal is stored in the memory 13 so that the voice signal can be transmitted to the wireless circuit 11 without a time lag. However, the voice signal is stored in the memory 13 only during a period from when transmission becomes impossible to when transmission becomes possible. A voice signal (sending contents) may be stored.

The inventions other than the claims that can be grasped from the above embodiment will be described below together with their effects. (1) In the communication system according to claim 4 , the sending means (11, 12) and the recording means (13, 14, 15).
And a control means (16) included in the communication terminal device.

(2) In the communication system according to the fifth aspect , the recording / reproducing means (13, 14, 15), the sending means (11, 12) and the control means (16) are included in a communication terminal device. A communication system, comprising: According to the inventions described in the above (1) and (2), it is possible to obtain a communication terminal device capable of smoothly performing communication even when communication is interrupted.

[0045]

As described above, according to the present invention, communication can be performed smoothly even if communication is interrupted.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a mobile telephone communication system according to an embodiment;

FIG. 2 is a flowchart showing the operation of the mobile telephone communication system.

FIG. 3 is an explanatory diagram for explaining a speech speed conversion technique.

[Explanation of symbols]

Reference numeral 3 denotes a radio network controller serving as a judgment means, 11 a radio circuit, 12 a voice circuit (11 and 12 constitute transmission means), 13 memories, 14 a write address counter, and 15 a read address counter (13 , 14,15
Constitute recording means and recording / reproducing means. ), 16 ...
Control circuit as control means.

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04B ⁷ /24-7/26 H04M 1/00 H04Q 7/00-7/38

Claims (6)

(57) [Claims] The present invention determines whether communication is possible by monitoring the state of a communication signal according to communication contents, and records communication contents during a period when communication is determined to be impossible based on a result of the determination. Then, when it is determined that communication is possible,
A communication method characterized in that recorded communication contents are reproduced at a high speed in order to eliminate a time delay of communication caused by a communication unavailable period. 2. Recording and reproduction of communication contents at a first speed.
While transmitting a communication signal corresponding to the reproduced communication content.
Outgoing communication signal in the communication method
Determines whether communication is possible by monitoring the status of signals
Based on the determination result,
Playback was interrupted and only communication contents were recorded
Later, when it is determined that communication is possible, the recorded communication contents
The communication time delay caused by the
A second speed, higher than the first speed, to be erased
A communication method, characterized in that the communication is reproduced by a computer. 3. The communication method according to claim 2, wherein
Playback of all communication contents recorded during the communication unavailable period
Switch from the second speed to the first speed
Communication that records and plays back communication contents.
How to trust. 4. A transmission for transmitting a communication signal according to communication contents.
Output means (11, 12) and the state of the communication signal transmitted by the transmission means are monitored.
Determining means for determining whether communication is possible or not
(3) recording means for recording the communication contents (13, 14, 15)
If, on the basis of the determination means (3) of the determination result, the incommunicable
In order to record the communication content during the determined period,
Control the recording means and determine that communication is possible
And the communication contents recorded in the recording means cannot be communicated.
The time delay of communication caused by the period is eliminated.
Control means for controlling the recording means in order to reproduce at such a high speed
A communication system comprising: a stage (16). 5. A method for recording and reproducing communication contents at a first speed.
Recording / reproducing means (13, 14, 15) and communication means reproduced according to the communication contents reproduced by the recording / reproducing means.
To monitor the feed detecting means transmits a communication signal (11, 12), the state of the communication signal transmitted by the transmitting means
Determining means for determining whether communication is possible or not
(3) and, based on the determination result of the determination means (3), communication is disabled.
Stop playback during the determined period and record communication contents
Control the recording / reproducing means to perform only
At the time when it is determined that communication is possible,
The communication contents recorded in the
The first speed so that the time delay of communication is eliminated.
Recording / reproducing means for reproducing at a higher second speed.
And control means (16) for controlling the step.
Communication system. 6. The communication system according to claim 5, wherein
The control means (16) is configured to determine whether the communication
After all of the communication contents recorded by the
Switching from the speed to the first speed and recording communication contents
Controlling the recording / reproducing means for reproducing.
A communication system characterized by the above-mentioned.