JP4079921B2 - Wireless IP telephone, wireless IP telephone system, and voice communication method thereof - Google Patents

Description

  The present invention relates to a wireless IP telephone using a wireless LAN, a wireless IP telephone system, and a voice communication method thereof.

  Conventionally, as voice communication means using a wireless public network, there are MCA (Multi Channel Access) radio, commercial radio, mobile phone, and the like mounted on a vehicle such as a distribution truck. In addition, in the United States, a multi-call service that enables communication with a plurality of users by push-to-talk is realized in a mobile phone. In this method, half-duplex calls such as transceivers are performed between users using a data channel of a mobile phone.

By the way, in the voice call by the above-mentioned MCA radio, business radio, etc., the time that one user occupies the call channel is limited, and it is not possible to make a long-time call. There is a disadvantage that the area is narrow.
On the other hand, mobile phones have a wider service area compared to MCA radio etc., but on the other hand, as long as the call connection (wireless line is connected), the call is connected regardless of whether the user is talking or not. There is a drawback that it is expensive because it is charged depending on the time.

  In addition, unlike the normal telephone protocol, the push-to-talk on the mobile phone described above allows a call to be made at any time without making a call in a state in which the parties making a call have a session, and is very inexpensive. The service can be received at a flat rate, but it is necessary to prepare a dedicated channel for voice messages in the mobile phone network system, and it cannot be used when the mobile phone operator does not provide the service.

  By the way, in recent years, with the development of telecommunications technology, IP phones using the Internet communication technology based on the IP protocol have become widespread, and wireless IP phones using a wireless LAN have appeared. The IP phone and the wireless IP phone are advantageous in that the communication cost is particularly low as compared with the conventional mobile phone.

On the other hand, Patent Document 1 discloses a technique for measuring a delay time caused by transmission in a communication network in which data is transmitted from a transmission side to a reception side via an asynchronous transmission network.
JP 2001-244932 A

  However, in the case of a wireless IP telephone using a wireless LAN, the bandwidth is limited as compared with wired broadband and the like, and since the wireless is used, the call quality is always influenced by the state of radio waves. In particular, when the radio wave condition deteriorates, the error rate increases, which increases the amount of transmission delay of voice signal packets, and sounds are unnaturally heard. In particular, hands-free wireless IP telephones generate echo. This is a problem because the call quality may deteriorate significantly.

  Here, the echo described above will be described in detail. First, in the wireless IP telephone, the voice uttered by the user is transmitted as a voice signal packet from the microphone to the partner wireless IP telephone, and the partner wireless IP telephone Although the sound is output from the speaker, the microphone of the other party's wireless IP telephone picks up a part of the received voice and may be reversely transmitted to the user's wireless IP telephone as it is.

  In this case, the user listens to the voice he / she uttered via the transmission path of the wireless IP phone. At this time, the voice heard by the user via the transmission path is a so-called echo (the voice spoken by the user is echoed) with a time delay corresponding to the delay amount of the voice signal packet compared to the voice emitted by the user. It will be recognized as.)

  In the end-to-end communication between wireless IP telephones using a wireless LAN in view of the above problems, the present invention is a case where an echo occurs due to deterioration of radio wave conditions during a user's call. It is an object of the present invention to provide a wireless IP telephone, a wireless IP telephone system, and a voice communication method thereof that allow a user to always maintain stable call quality without feeling uncomfortable due to echo.

According to the first aspect of the present invention, when an end-to-end call between wireless IP telephones using a wireless LAN is being made by a user, the data output unit is a packet assembling unit every time a predetermined time elapses by a timer. On the other hand, the delay measurement data is output, and at the same time, the header generation unit obtains a time stamp of the output time of the delay measurement data from the clock unit, stores the time stamp in the header, and the header generation unit The stored header is sent to the packet assembly unit, and the packet assembly unit adds the header sent from the header generation unit to the delay measurement data sent from the data output unit, and assembles into a delay measurement packet, The packet for delay measurement assembled by the packet communication control unit is sent to the wireless IP phone on the other end of communication It is,
In the loopback unit, the time stamp is extracted from the sent delay measurement packet, stored in the header of the reply audio signal packet, the reply delay measurement packet is returned, and the reply delay measurement When the packet is returned from the other party's wireless IP phone, the packet decomposing unit decomposes the received delay measurement packet, extracts the time stamp from the header, and sends the extracted time stamp to the calculating unit. The calculation unit calculates a transmission delay amount by calculating a difference between the sent time stamp and the time when the reply delay measurement packet is received, and the transmission delay amount is equal to or larger than a predetermined value. A delay detection unit that determines that a delay has occurred, and a delay detection unit that determines that a delay has occurred. No. is the case it is confirmed that the detected, stops the detection of the speech signal, characterized in that the wireless IP phone having a packet transmission control unit does not transmit the uplink voice signal packets.

  The invention described in claim 2 is the wireless IP telephone set according to claim 1, further comprising a packet transmission time adjusting unit for adjusting a transmission time of the uplink voice signal packet.

  The invention according to claim 3 is the wireless IP telephone according to claim 1 or 2, further comprising a talk mode lamp for letting a user know that the talk mode is in the wireless IP telephone. And

According to a fourth aspect of the present invention, in a case where a user is in a call during an end-to-end call between wireless IP telephones using a wireless LAN, the data output unit is a packet assembling unit every time a predetermined time elapses due to a timer. On the other hand, the delay measurement data is output, and at the same time, the header generation unit obtains a time stamp of the output time of the delay measurement data from the clock unit, stores the time stamp in the header, and the header generation unit The stored header is sent to the packet assembly unit, and the packet assembly unit adds the header sent from the header generation unit to the delay measurement data sent from the data output unit, and assembles into a delay measurement packet, The packet for delay measurement assembled by the packet communication control unit is sent to the wireless IP phone on the other end of communication It is,
In the loopback unit, the time stamp is extracted from the sent delay measurement packet, stored in the header of the reply audio signal packet, the reply delay measurement packet is returned, and the reply delay measurement When the packet is returned from the other party's wireless IP phone, the packet decomposing unit decomposes the received delay measurement packet, extracts the time stamp from the header, and sends the extracted time stamp to the calculating unit. The calculation unit calculates a transmission delay amount by calculating a difference between the sent time stamp and the time when the reply delay measurement packet is received, and the transmission delay amount is equal to or larger than a predetermined value. In addition, when it is confirmed that a delay detection unit that determines that a delay has occurred and that the microphone audio signal is detected in the other party's wireless IP phone, A wireless IP telephone system including two or more wireless IP telephones including a packet transmission control unit for stopping transmission of voice signal packets, wherein the delay detection unit determines that a delay has occurred in the wireless IP telephone. When the voice signal from the microphone is detected, the packet transmission control unit of the other party's wireless IP telephone stops detecting the voice signal and does not transmit the upstream voice signal packet. It is characterized by that.

  According to a fifth aspect of the present invention, in the wireless IP telephone, when the delay control unit determines that a transmission delay has occurred, the wireless IP telephone starts half-duplex mode with respect to the partner wireless IP telephone. The other party's wireless IP phone that has received the request notification transmits a half-duplex mode start confirmation notification to the wireless IP phone, waits for a microphone audio signal detection, and starts the half-duplex mode. The wireless IP phone that has received the confirmation notification waits for microphone audio signal detection. When a microphone audio signal is detected thereafter, the wireless IP phone transmits a microphone audio signal detection start notification to the other party's wireless IP phone. The other party's wireless IP phone that has received the audio signal detection start notification is in speaker mode, and packet transmission control is performed. The packet transmission of the uplink voice signal is stopped by the unit, and after the wireless IP telephone transmits a microphone voice signal detection start notification to the other party's wireless IP telephone, the packet transmission stop of the uplink voice signal is canceled, The voice signal detected from the microphone is sequentially converted into a packet signal, and the converted packet signal is transmitted to the other party's wireless IP telephone. When the microphone voice signal is not detected, the other party's wireless IP telephone is sent. A microphone audio signal detection end notification is transmitted to return to the microphone audio detection waiting state, and the partner wireless IP phone that has received the microphone audio signal detection end notification from the wireless IP phone returns from the speaker mode to the microphone audio detection waiting state. Item 4. A wireless IP telephone system according to item 4.

  In the invention according to claim 6, the radio wave condition of the wireless IP telephone is improved, and in the delay control unit of the wireless IP telephone, the transmission delay amount of the delay measurement packet is reduced to a predetermined value or less, and the transmission delay is recovered. The wireless IP telephone transmits a half-duplex mode release request notification to the counterpart wireless IP telephone, and receives the half-duplex mode release request notice. Transmits a half-duplex mode release request confirmation notification to the wireless IP phone to cancel the half-duplex mode, and the wireless IP phone that has received the transmitted half-duplex mode release request confirmation notification The wireless IP telephone system according to claim 4 or 5, wherein the half duplex mode is canceled.

  The invention according to claim 7 is the wireless IP telephone system according to any one of claims 4 to 6, further comprising a packet transmission time adjustment unit for adjusting a transmission time of the uplink voice signal packet. It is characterized by.

  The wireless IP telephone according to any one of claims 4 to 7, wherein the wireless IP telephone further comprises a talk mode lamp for letting a user know that the telephone is in the talk mode. It is a system.

According to the ninth aspect of the present invention, in a case where a user is in a call during an end-to-end call between wireless IP telephones using a wireless LAN, the data output unit is provided with a packet assembly unit every time a predetermined time elapses by a timer. On the other hand, the delay measurement data is output, and at the same time, the header generation unit obtains a time stamp of the output time of the delay measurement data from the clock unit, stores the time stamp in the header, and the header generation unit The stored header is sent to the packet assembly unit, and the packet assembly unit adds the header sent from the header generation unit to the delay measurement data sent from the data output unit, and assembles into a delay measurement packet, The packet for delay measurement assembled by the packet communication control unit is sent to the wireless IP phone on the other end of communication It is,
In the loopback unit, the time stamp is extracted from the sent delay measurement packet, stored in the header of the reply audio signal packet, the reply delay measurement packet is returned, and the reply delay measurement When the packet is returned from the other party's wireless IP phone, the packet decomposing unit decomposes the received delay measurement packet, extracts the time stamp from the header, and sends the extracted time stamp to the calculating unit. The calculation unit calculates the difference between the time stamp sent and the time when the reply delay measurement packet is received, calculates the transmission delay amount, and the delay detection unit measures the delay at predetermined time intervals. A delay detection step of detecting a transmission delay amount of the packet for use and determining a delay occurrence state when the transmission delay amount is equal to or greater than a predetermined value; and a delay detection step Ri is determined that the delay generating state, when the microphone audio signals in the other party of the wireless IP telephone has confirmed that it has been detected, the packet transmission control unit stops the detection of the speech signal, transmitting uplink speech signal packet A voice communication method for a wireless IP telephone including a packet transmission control step that is not performed .

  The invention according to claim 10 is the voice communication method for a wireless IP telephone according to claim 9, further comprising a packet transmission time adjustment step of adjusting a transmission time of the uplink voice signal packet by a packet transmission time adjustment unit. It is characterized by.

  The invention according to claim 11 further comprises a step of notifying the user that the wireless IP telephone is in the talk mode by turning on or blinking the talk mode lamp when the wireless IP telephone is in the talk mode. 10. The voice communication method for a wireless IP telephone set according to No.10.

According to a twelfth aspect of the present invention, when an end-to-end call is being made between wireless IP telephones using a wireless LAN and a user is on a call, the data output unit is a packet assembling unit every time a predetermined time elapses due to a timer. On the other hand, the delay measurement data is output, and at the same time, the header generation unit obtains a time stamp of the output time of the delay measurement data from the clock unit, stores the time stamp in the header, and the header generation unit The stored header is sent to the packet assembly unit, and the packet assembly unit adds the header sent from the header generation unit to the delay measurement data sent from the data output unit, and assembles into a delay measurement packet, The delay measurement packet assembled by the packet communication control unit is sent to the wireless IP phone on the other end of communication. It is,
In the loopback unit, the time stamp is extracted from the sent delay measurement packet, stored in the header of the reply audio signal packet, the reply delay measurement packet is returned, and the reply delay measurement When the packet is returned from the other party's wireless IP phone, the packet decomposing unit decomposes the received delay measurement packet, extracts the time stamp from the header, and sends the extracted time stamp to the calculating unit. The calculation unit calculates the difference between the time stamp sent and the time when the reply delay measurement packet is received, calculates the transmission delay amount, and the delay detection unit measures the delay at predetermined time intervals. A delay detection step of detecting a transmission delay amount of the packet for use and determining a delay occurrence state when the transmission delay amount is equal to or greater than a predetermined value; A packet transmission control step of stopping transmission of an upstream voice signal packet by a packet transmission control unit when it is confirmed that a microphone voice signal is detected in the IP telephone. A voice communication method for a wireless IP telephone system, wherein in the wireless IP telephone, when it is determined that a delay has occurred in the delay detection step and a voice signal from a microphone is detected, In the wireless IP telephone, the packet transmission control unit of the wireless IP telephone has a voice communication method for a wireless IP telephone system including a step of stopping detection of a voice signal and not transmitting an upstream voice signal packet. And

  According to the thirteenth aspect of the present invention, when it is determined in the wireless IP telephone that a transmission delay has occurred in the delay detection step, the wireless IP telephone starts half-duplex mode with respect to the partner wireless IP telephone. A step of transmitting a request notification, and the other party's wireless IP telephone receiving the notification transmits a half-duplex mode start confirmation notification to the wireless IP telephone and waits for a microphone voice signal detection; The wireless IP phone that has received the half-duplex mode start confirmation notification waits for microphone audio signal detection, and when a microphone audio signal is detected thereafter, sends a microphone audio signal detection start notification to the partner wireless IP phone. The other party's wireless IP phone that has received the microphone audio signal detection start notification The packet transmission control unit stops the packet transmission of the uplink voice signal, and the wireless IP telephone transmits the microphone voice signal detection start notification to the partner wireless IP telephone, Cancel the packet transmission stop, sequentially convert the audio signal detected from the microphone into a packet signal, transmit the converted packet signal to the wireless IP telephone of the other side, when the microphone audio signal is not detected, Transmitting a microphone audio signal detection end notification to the counterpart wireless IP phone and returning to a microphone audio detection waiting state; and receiving the microphone audio signal detection end notification from the wireless IP phone, And a step of returning from the mode to a microphone voice detection waiting state. And characterized in that a voice communication method of the scan IP telephone system.

  In the invention according to claim 14, the radio wave condition of the wireless IP telephone is improved, and in the delay control unit of the wireless IP telephone, the transmission delay amount of the delay measurement packet is reduced to a predetermined value or less, and the transmission delay is recovered. The wireless IP telephone transmits a half-duplex mode release request notification to the counterpart wireless IP telephone and the counterpart wireless that has received the half-duplex release request notification. The IP telephone transmits a half-duplex mode release request confirmation notification to the wireless IP telephone to cancel the half-duplex mode, and the wireless that has received the transmitted half-duplex mode release request confirmation notification 14. The IP telephone according to claim 12, further comprising a step of canceling the half-duplex mode. And wherein the door.

  The invention according to claim 15 further includes a packet transmission time adjustment step of adjusting a transmission time of the uplink voice signal packet by a packet transmission time adjustment unit, according to any one of claims 12 to 14. It is characterized by the voice communication method of the telephone system.

  The invention according to claim 16 further comprises the step of notifying the user that the wireless IP telephone is in the talk mode by lighting or blinking the talk mode lamp when the wireless IP telephone is in the talk mode. 15. The voice communication method for a wireless IP telephone system according to any one of 15 above.

  According to the present invention, in end-to-end communication between wireless IP telephones using a wireless LAN, even when an echo is generated due to deterioration of radio wave conditions during a user's call, the user feels uncomfortable due to the echo. You can always maintain a stable call quality without having to remember.

  The best mode for carrying out the present invention is to detect a transmission delay amount of a delay measurement packet every predetermined time during an end-to-end call between wireless IP telephones in a wireless IP telephone using a wireless LAN. When the transmission delay amount is equal to or greater than a predetermined value, a delay detection unit that determines that a delay has occurred, and an upstream audio signal packet when it is confirmed that a microphone audio signal has been detected in the partner wireless IP telephone And a packet transmission control unit for stopping transmission.

(First embodiment)
Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. Unless otherwise described, the present invention is not limited to these embodiments.

  First, a schematic configuration and functions of a wireless IP telephone according to the present embodiment will be described with reference to FIG. FIG. 1 is a configuration block diagram of a wireless IP telephone according to the present embodiment. As shown in FIG. 1, the wireless IP telephone 15 of this embodiment includes a microphone 1, a microphone amplifier 2, an audio signal detection unit 3, an A / D conversion unit 4, a packet assembly unit 5, a packet communication control unit 6, and a main control. Unit 7, delay detection unit 8, antenna 9, packet transmission control unit 10, packet decomposition unit 11, D / A conversion unit 12, speaker amplifier 13, and speaker 14.

The microphone 1 inputs the voice uttered by the user to the wireless IP telephone 15. The microphone amplifier 2 is provided to adjust the input value of the input audio signal to an appropriate value. The audio signal detector 3 detects an audio signal from the microphone 1. The A / D converter 4 converts the upstream audio signal from the microphone 1 from an analog signal to a digital signal, and performs data compression.
The packet assembling unit 5 assembles an audio signal packet based on the digital signal converted by the A / D conversion unit 4. When the other party's wireless IP telephone determines that a delay has occurred and the packet transmission control unit 6 confirms that a microphone voice signal has been detected, the packet transmission control unit 6 stops transmitting the uplink voice signal packet.

  The main control unit 7 also controls each part of the wireless IP telephone and performs IP telephone call connection processing. The delay detection unit 8 detects the transmission delay amount of the delay measurement packet, and determines that a delay has occurred when the delay amount increases to a predetermined value or more. The antenna 9 transmits and receives voice signal packets to and from the other party's wireless IP phone via the IP network. The packet communication control unit 10 performs call connection and data communication with the IP telephone network. The packet decomposition unit 11 decomposes the transmitted audio signal packet and converts it into a digital signal. The D / A converter 12 converts the downlink audio signal from the partner side, which has been subjected to data compression, from a digital signal to an analog signal. The speaker amplifier 13 is provided to adjust the output value of the output audio signal to an appropriate value. The speaker 14 outputs a voice uttered by the other user.

  Next, when the delay in the transmission path of the voice signal packet increases due to the deterioration of the radio state, the delay detection unit 8 detects the transmission delay amount of the delay measurement packet and performs this implementation until it is determined that the delay is generated. The operation of the wireless IP telephone according to the embodiment will be described in detail below with reference to FIGS. FIG. 2 is a configuration block of the delay detection unit 8 shown in FIG. As shown in FIG. 2, the delay detection unit 8 includes a data output unit 101, a clock unit 102, a header generation unit 103, a packet assembly unit 104, a packet decomposition unit 105, and a calculation unit 106. FIG. 3 is a flowchart for explaining a method by which the delay detector 8 shown in FIG. 2 calculates the delay amount in the transmission path of the delay measurement packet.

  First, as shown in FIG. 3, when the wireless IP telephone 15 of the present embodiment shown in FIG. 1 is in a call by a user, a timer (not shown) is used here for every predetermined time (step 101). The data output unit 101 shown outputs delay measurement data to the packet assembly unit 104 (step 102). At the same time, the header generation unit 103 obtains the time stamp of the output time of the delay measurement data from the clock unit 102 shown in FIG. 2, and stores the time stamp in the header (step 103).

  Subsequently, the header generation unit 103 shown in FIG. 2 sends the header storing the time stamp to the packet assembly unit 104 shown in FIG. Then, the packet assembly unit 104 adds the header sent from the header generation unit 103 to the delay measurement data sent from the data output unit 101, assembles it into a delay measurement packet, and the packet shown in FIG. The delay measurement packet assembled by the communication control unit 10 is transmitted to the wireless IP telephone on the other side during communication (step 105).

  Subsequently, in the loopback unit (not shown) provided in the other party's wireless IP phone, the time stamp is extracted from the sent delay measurement packet and stored in the header of the reply audio signal packet. The reply delay measurement packet is returned to the wireless IP telephone set 15.

  The wireless IP telephone 15 of the present embodiment is also provided with a loopback unit in the delay detection unit 8 (not shown), and the loopback unit receives a delay measurement packet sent from the partner wireless IP telephone set. Receive and return a delay measurement packet to the other party's IP phone.

  Subsequently, when a reply delay measurement packet is returned from the other party's wireless IP telephone (YES in step 106), the packet disassembling unit 105 shown in FIG. 2 disassembles the received reply delay measurement packet. Then, a time stamp is extracted from the header (step 108), and the extracted time stamp is sent to the calculation unit 106. Then, the calculation unit 106 shown in FIG. 2 calculates a difference between the sent time stamp and the time when the reply delay measurement packet is received, thereby calculating a transmission delay amount (step 109). .

  As described above, the delay detection unit 8 provided in the wireless IP telephone 15 of the present embodiment operates to detect the transmission delay amount of the delay measurement packet every predetermined time while the user is talking. The delay detection unit 8 determines that a transmission delay has occurred when the transmission delay amount of the detected delay measurement packet increases beyond the allowable range.

  Next, as described above, when the delay detection unit 8 in the wireless IP telephone 15 according to the present embodiment determines that a transmission delay has occurred, the wireless IP telephone 15 performs full duplex communication (a normal two-way telephone). The operation contents when switching from pseudo communication mode to pseudo half-duplex communication (calling method such as a one-way radio) will be described in detail below with reference to FIGS.

  FIG. 4 is a diagram for explaining the operation contents when the wireless IP telephone 15 of the present embodiment performs a switching operation from full duplex communication to pseudo half duplex communication. In FIG. 4, it is assumed that communication is performed between the terminal 1 (the wireless IP telephone 15 according to the present embodiment) and the terminal 2 (the wireless IP telephone 15 according to the other embodiment).

  First, as shown in FIG. 4, the delay control unit 8 (see FIG. 1) of the terminal 1 determines that the transmission delay amount of the delay measurement packet has increased to a predetermined value or more and a transmission delay has occurred. In the case (step 201), the terminal 1 transmits a half-duplex mode start request notification to the partner terminal 2 (step 202). When the partner terminal 2 receives this half-duplex mode start request notification, the terminal 2 transmits a half-duplex mode start confirmation notice to the terminal 1 (step 203), and waits for microphone audio signal detection (speaker). Mode) (step 204).

  Similarly, when the terminal 1 receives the half-duplex mode start confirmation notification from the terminal 2, it enters a microphone audio signal detection wait (speaker mode) (step 205). In the speaker mode, the packet transmission control unit 6 shown in FIG. Subsequently, when a microphone audio signal is detected in the terminal 1, the terminal 1 transmits a microphone audio signal detection start notification to the terminal 2 (step 206). When the terminal 2 receives the microphone audio signal detection start notification received from the terminal 1, the audio signal detection unit 3 shown in FIG. 1 stops the audio signal detection (step 207).

Subsequently, after transmitting the microphone audio signal detection start notification to the terminal 2, the terminal 1 enters the talk mode (step 208) and cancels that the packet transmission of the uplink audio signal has been stopped until then. The audio signal detected from the microphone 1 is sequentially converted into an audio signal packet by the A / D conversion unit 4, the packet assembly unit 5, and the like, and transmitted to the terminal 2 (step 209). Next, when the microphone sound signal is not detected, the terminal 1 transmits a microphone sound signal detection end notification to the terminal 2 (step 210), and returns to the microphone sound detection waiting state (step 211). Similarly, the terminal 2 receives the microphone audio signal detection end notification from the terminal 1 returns to the microphone voice detection wait state (step 212).

  As described above, according to the wireless IP telephone 15 of this embodiment, when a transmission delay occurs due to deterioration of radio wave conditions during a user's call, the packet transmission control unit 6 of the other party's wireless IP telephone can By stopping upstream voice signal packet transmission, switching from normal full-duplex communication to pseudo half-duplex communication is possible, and transmission of voice signal packets is only one-way. It is possible to obtain the effect of preventing the occurrence of echoes caused by the microphone of the wireless IP telephone on the side picking up a part of the received voice and back-transmitting it directly to the wireless IP telephone 15 of this embodiment.

  Next, when the radio wave condition is improved after the wireless IP telephone 15 of the present embodiment performs the switching operation to the pseudo half duplex communication described above, the half duplex communication is canceled and the full duplex communication is performed. The contents of the switching operation will be described in detail below with reference to FIG. 1, mainly using FIG. FIG. 5 is a sequence diagram for explaining the content of the switching operation from pseudo half-duplex communication to full-duplex communication in the wireless IP telephone 15 of the present embodiment. In FIG. 5, it is assumed that communication is performed between the terminal 1 (the wireless IP telephone 15 of the present embodiment) and the terminal 2 (the wireless IP telephone 15 of the other party of the present embodiment).

  First, as shown in FIG. 5, the radio wave condition of the terminal 1 is improved, and in the delay control unit 8 (see FIG. 1) of the terminal 1, the transmission delay amount of the delay measurement packet is reduced to a predetermined value or less. When it is determined that the transmission delay has been recovered (step 301), the terminal 1 transmits a half duplex mode release request notification to the partner terminal 2 (step 302). The partner terminal 2 that has received the half duplex mode release request notification transmits a half duplex mode release request confirmation notice to the terminal 1 (step 303), cancels the half duplex mode, and releases the normal all The dual mode is set (step 304). Subsequently, when the terminal 1 receives the half-duplex mode release request confirmation notification transmitted from the terminal 2, the terminal 1 cancels the half-duplex mode and enters the normal full-duplex mode (step 305).

(Second Embodiment)
This embodiment is a modification of the wireless IP telephone 15 in the first embodiment shown in FIG. FIG. 8 is a block diagram showing the configuration of the wireless IP telephone 15 according to the present embodiment. The wireless IP telephone 15 of this embodiment is characterized in that a packet transmission time adjustment unit 17 is provided as shown in FIG. 8 in addition to the configuration of the wireless IP telephone 15 in the first embodiment shown in FIG. To do.

  Here, with reference to FIGS. 1 and 4, mainly FIGS. 6 and 7, in the wireless IP telephone 15 of the present embodiment, the operation until the audio signal input from the microphone 1 is transmitted as an audio signal packet. The contents will be described in detail. FIG. 6 is a diagram for explaining the operation contents until the audio signal input from the microphone 1 is transmitted as an audio signal packet in the wireless IP telephone 15 (terminal 1 in FIG. 4) of the present embodiment shown in FIG. It is a 1st timing chart. FIG. 7 is a diagram for explaining the operation contents until the voice signal input from the microphone 1 is transmitted as a voice signal packet in the wireless IP telephone 15 (terminal 1 in FIG. 4) of the present embodiment shown in FIG. It is a 2nd timing chart.

  First, as shown in FIG. 6, at time T <b> 1, the user begins to speak, the audio signal S is input from the microphone 1 of the terminal 1 shown in FIG. 4, and the audio signal detection unit 3 detects the audio signal. This is the time required (see FIG. 1). When the audio signal is detected in the audio signal detection unit 3, the terminal 1 transmits a microphone audio signal detection start notification to the terminal 2 (FIG. 4: step 206), as shown in FIG. S1 during microphone sound detection.

  The time T2 is a time necessary for the main control unit 7 to switch the terminal 1 from the speaker mode to the talk mode S2 after the terminal 1 transmits the microphone audio signal detection start notification. The time T3 is a time required until the terminal 1 enters the uplink voice signal packet transmission stop cancellation state S3 after switching to the talk mode described above. Note that, when the uplink voice signal packet transmission stop cancellation state S3 is entered, the terminal 1 starts transmission of the voice signal packet.

  In the processing time T4, the voice uttered by the user is input as the voice signal S in the wireless IP telephone 15, and is converted from an analog signal to a digital signal by the A / D conversion unit 4, data compression is performed, and the packet assembly unit 5 is a time required for the packet to be transmitted from the packet communication control unit 10 to the wireless IP telephone 15 on the other side after being assembled into a packet and queued in the transmission buffer (see FIG. 1).

  Here, as shown in FIG. 6, when the time T3 is shorter than the time T4, the voice signal packet can be transmitted after the uplink voice packet transmission stop cancellation state S3 (S4). The voice signal S input from the microphone 1 of the terminal 1 when the user starts to speak is all transmitted to the counterpart terminal 2 as a voice signal packet. For this reason, all the voices spoken by the user are transmitted to the terminal 2, and the other party can hear all the contents of the user's call.

  However, as shown in FIG. 7, when the time T3 is longer than the time T4, the voice signal packet can be transmitted before the uplink voice packet transmission stop cancellation state S3 is reached (S4). The audio signal packet corresponding to the head signal of the audio signal S input from the microphone 1 of the terminal 1 is not transmitted to the counterpart terminal 2 for the time T5 shown in FIG. Therefore, in this case, the voice at the beginning of the user's talk will be lost, and the other party will hear the voice uttered by the user after time T5 has elapsed since the user began to talk.

  In order to solve this problem, in the wireless IP telephone set 15 of this embodiment, as shown in FIG. 6, the packet transmission time adjustment unit 17 for adjusting the time T4 so that the time T3 is shorter than the time T4. (See FIG. 8). As a result, the wireless IP telephone 15 always operates so as to be able to transmit voice signal packets after entering the uplink voice packet transmission stop cancellation state S3 (S4). Therefore, since all the voice signals S input to the terminal 1 by the user are transmitted as voice signal packets to the terminal 2 on the other side, the other side can hear all the contents of the user's call.

(Third embodiment)
This embodiment is a modification of the wireless IP telephone 15 in the first embodiment shown in FIG. FIG. 9 is a block diagram showing the configuration of the wireless IP telephone 15 of this embodiment. The wireless IP telephone 15 of this embodiment is characterized in that a talk mode lamp 16 is provided as shown in FIG. 9 in addition to the configuration of the wireless IP telephone 15 in the first embodiment shown in FIG. It is. The talk mode lamp 16 is provided for confirming whether or not the wireless IP telephone 15 is in the talk mode when the user is talking.

1 is a block diagram showing a configuration of a wireless IP telephone according to a first embodiment to which the present invention is applied. It is a block diagram of the configuration of a delay detection unit provided in the wireless IP telephone according to the present embodiment. 6 is a flowchart for explaining a method of calculating a delay amount in a transmission path of a delay measurement packet by a delay detection unit provided in the wireless IP telephone according to the present embodiment. It is a sequence diagram for demonstrating the operation | movement content in case the wireless IP telephone of this embodiment performs switching operation | movement from full duplex communication to pseudo | simulation half duplex communication. It is a sequence diagram for demonstrating the operation | movement content in case the wireless IP telephone of this embodiment performs switching operation | movement from pseudo | simulation half duplex communication to full duplex communication. 6 is a first timing chart for explaining an operation until a voice signal input from a microphone is transmitted as a voice signal packet in the wireless IP telephone according to the present embodiment. 6 is a second timing chart for explaining an operation until a voice signal input from a microphone is transmitted as a voice signal packet in the wireless IP telephone according to the present embodiment. It is a structure block diagram of the wireless IP telephone set in 2nd Embodiment to which this invention is applied. It is a block diagram of the configuration of a wireless IP telephone in a third embodiment to which the present invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Microphone 2 Microphone amplifier 3 Audio | voice signal detection part 4 A / D conversion part 5 Packet assembly part 6 Packet transmission control part 7 Main control part 8 Delay detection part 9 Antenna 10 Packet communication control part 11 Packet decomposition part 12 D / A conversion part DESCRIPTION OF SYMBOLS 13 Speaker amplifier 14 Speaker 15 Wireless IP telephone 16 Talk mode lamp 17 Packet transmission time adjustment part 101 Data output part 102 Clock part 103 Header production | generation part 104 Packet assembly part 105 Packet decomposition part 106 Calculation part

Claims (16)

During an end-to-end call between wireless IP telephones using a wireless LAN, when the user is on a call, the data output unit sends delay measurement data to the packet assembly unit every time a predetermined time elapses due to a timer. At the same time, the header generation unit obtains a time stamp of the output time of the delay measurement data from the clock unit, stores the time stamp in the header, and the header generation unit reads the header in which the time stamp is stored. The packet assembly unit adds the header sent from the header generation unit to the delay measurement data sent from the data output unit, assembles the packet into a delay measurement packet, and controls packet communication. The delay measurement packet assembled by the communication unit is transmitted to the wireless IP phone on the other side during communication.
In the loopback unit, the time stamp is extracted from the sent delay measurement packet, stored in the header of the reply audio signal packet, the reply delay measurement packet is returned, and the reply delay measurement is performed. Packet is returned from the other party's wireless IP telephone, the packet disassembly unit disassembles the received reply delay measurement packet, extracts the time stamp from the header, and calculates the extracted time stamp. The calculation unit calculates a transmission delay amount by calculating a difference between the sent time stamp and the time when the reply delay measurement packet is received, and the transmission delay amount is predetermined. A delay detection unit that determines a delay occurrence state when the value is equal to or greater than a value;
When the delay detection unit determines that a delay has occurred and confirms that the microphone audio signal has been detected in the wireless IP telephone of the other party, the detection of the audio signal is stopped and the uplink audio signal packet is not transmitted . A packet transmission control unit;
A wireless IP telephone comprising:   2. The wireless IP telephone according to claim 1, further comprising a packet transmission time adjusting unit for adjusting a transmission time of the uplink voice signal packet.   The wireless IP telephone according to claim 1 or 2, further comprising a talk mode lamp for letting a user know that the talk mode is in the wireless IP telephone. During an end-to-end call between wireless IP telephones using a wireless LAN, when the user is on a call, the data output unit sends delay measurement data to the packet assembly unit every time a predetermined time elapses due to a timer. At the same time, the header generation unit obtains a time stamp of the output time of the delay measurement data from the clock unit, stores the time stamp in the header, and the header generation unit reads the header in which the time stamp is stored. The packet assembly unit adds the header sent from the header generation unit to the delay measurement data sent from the data output unit, assembles the packet into a delay measurement packet, and controls packet communication. The delay measurement packet assembled by the communication unit is transmitted to the wireless IP phone on the other side during communication.
In the loopback unit, the time stamp is extracted from the transmitted delay measurement packet, stored in the header of the reply audio signal packet, the reply delay measurement packet is returned, and the reply delay measurement is performed. Packet is returned from the other party's wireless IP telephone, the packet disassembly unit disassembles the received reply delay measurement packet, extracts the time stamp from the header, and calculates the extracted time stamp. The calculation unit calculates a transmission delay amount by calculating a difference between the sent time stamp and the time when the reply delay measurement packet is received, and the transmission delay amount is predetermined. If the value is equal to or greater than the value, it is confirmed that the delay detection unit that determines that a delay has occurred and that the microphone audio signal has been detected in the wireless IP phone on the other side. When, a wireless IP telephone system comprising a packet transmission control unit to stop sending the uplink voice signal packets, the wireless IP telephone set having two or more,
In the wireless IP telephone set, when the delay detection unit determines that a delay has occurred and confirms that a voice signal from the microphone has been detected, the packet transmission control unit of the partner wireless IP telephone detects the voice signal. And a wireless IP telephone system characterized by not transmitting uplink voice signal packets .   In the wireless IP telephone, when the delay control unit determines that a transmission delay has occurred, the wireless IP telephone transmits a half-duplex mode start request notification to the partner wireless IP telephone, and the notification The other party's wireless IP telephone that has received the message transmits a half-duplex mode start confirmation notice to the wireless IP telephone, waits for a microphone audio signal detection, and receives the half-duplex mode start confirmation notice. The phone waits for microphone audio signal detection, and when the microphone audio signal is detected thereafter, the microphone audio signal detection start notification is transmitted to the other party's wireless IP phone, and the microphone audio signal detection start notification is received. The other party's wireless IP phone is in speaker mode, and the packet transmission controller After the packet transmission is stopped, the wireless IP telephone transmits a microphone voice signal detection start notification to the partner wireless IP telephone, and then cancels the packet transmission stop of the upstream voice signal and detects the voice signal detected from the microphone. Are sequentially converted to packet signals, and the converted packet signals are transmitted to the other party's wireless IP telephone. When the microphone voice signal is not detected, the other party's wireless IP telephone is notified of the end of the microphone voice signal detection. The other party's wireless IP telephone that has received the microphone voice signal detection completion notification from the wireless IP telephone returns to the microphone voice detection waiting state from the speaker mode. 4. The wireless IP telephone system according to 4.   When the radio wave condition of the wireless IP telephone is improved and the delay control unit of the wireless IP telephone determines that the transmission delay amount of the delay measurement packet is reduced to a predetermined value or less and the transmission delay is recovered, The wireless IP phone transmits a half-duplex mode release request notification to the other-side wireless IP phone, and the other-side wireless IP phone that has received the half-duplex mode release request notification sends the half-duplex mode release request notification to the wireless IP phone. The half-duplex mode cancellation request confirmation notification is transmitted to cancel the half-duplex mode, and the wireless IP telephone receiving the transmitted half-duplex mode cancellation request confirmation notification cancels the half-duplex mode. The wireless IP telephone system according to claim 4 or 5.   The wireless IP telephone system according to any one of claims 4 to 6, further comprising a packet transmission time adjustment unit for adjusting a transmission time of the uplink voice signal packet.   The wireless IP telephone system according to any one of claims 4 to 7, further comprising a talk mode lamp for letting a user know that the wireless IP telephone is in the talk mode. During an end-to-end call between wireless IP telephones using a wireless LAN, when the user is on a call, the data output unit sends delay measurement data to the packet assembly unit every time a predetermined time elapses due to a timer. At the same time, the header generation unit obtains a time stamp of the output time of the delay measurement data from the clock unit, stores the time stamp in the header, and the header generation unit reads the header in which the time stamp is stored. The packet assembly unit adds the header sent from the header generation unit to the delay measurement data sent from the data output unit, assembles the packet into a delay measurement packet, and controls packet communication. The delay measurement packet assembled by the communication unit is transmitted to the wireless IP phone on the other side during communication.
In the loopback unit, the time stamp is extracted from the transmitted delay measurement packet, stored in the header of the reply audio signal packet, the reply delay measurement packet is returned, and the reply delay measurement is performed. Packet is returned from the other party's wireless IP telephone, the packet disassembly unit disassembles the received reply delay measurement packet, extracts the time stamp from the header, and calculates the extracted time stamp. The calculation unit calculates a difference between the received time stamp and the time when the reply delay measurement packet is received, calculates a transmission delay amount, and the delay detection unit A delay detection step of determining a delay occurrence state when the transmission delay amount is a predetermined value or more;
When it is determined by the delay detection step that a delay has occurred and it is confirmed that a microphone voice signal has been detected in the wireless IP telephone of the other party, the packet transmission control unit stops detecting the voice signal, and the upstream voice signal a packet transmission control process is not performed packet transmission,
A voice communication method for a wireless IP telephone.   10. The voice communication method for a wireless IP telephone according to claim 9, further comprising a packet transmission time adjustment step of adjusting a transmission time of the uplink voice signal packet by a packet transmission time adjustment unit.   11. The method according to claim 9, further comprising the step of notifying the user that the wireless IP telephone is in the talk mode by lighting or blinking the talk mode lamp when the wireless IP telephone is in the talk mode. Voice communication method for wireless IP telephones. During an end-to-end call between wireless IP telephones using a wireless LAN, when the user is on a call, the data output unit sends delay measurement data to the packet assembly unit every time a predetermined time elapses due to a timer. At the same time, the header generation unit obtains a time stamp of the output time of the delay measurement data from the clock unit, stores the time stamp in the header, and the header generation unit reads the header in which the time stamp is stored. The packet assembly unit adds the header sent from the header generation unit to the delay measurement data sent from the data output unit, assembles the packet into a delay measurement packet, and controls packet communication. The delay measurement packet assembled by the communication unit is transmitted to the wireless IP phone on the other side during communication.
In the loopback unit, the time stamp is extracted from the transmitted delay measurement packet, stored in the header of the reply audio signal packet, the reply delay measurement packet is returned, and the reply delay measurement is performed. Packet is returned from the other party's wireless IP telephone, the packet disassembly unit disassembles the received reply delay measurement packet, extracts the time stamp from the header, and calculates the extracted time stamp. The calculation unit calculates a transmission delay amount by calculating a difference between the sent time stamp and the time when the reply delay measurement packet is received. A delay detection step of detecting a transmission delay amount of the delay measurement packet every time, and determining that a delay occurs when the transmission delay amount is equal to or greater than a predetermined value; A packet transmission control step for stopping transmission of an upstream audio signal packet by a packet transmission control unit when it is confirmed that a microphone audio signal has been detected in the other party's wireless IP phone. A voice communication method for a wireless IP telephone system comprising the above,
In the wireless IP phone, when it is determined that the delay has occurred in the delay detection step and it is confirmed that the voice signal from the microphone is detected, the wireless IP phone on the other side transmits the packet of the wireless IP phone. control unit stops the detection of the voice signal, the voice communication method of the wireless IP telephone system comprising the step of not transmitting the uplink voice signal packets. In the wireless IP phone, when the delay detection step determines that a transmission delay has occurred, the wireless IP phone transmits a half-duplex mode start request notification to the partner wireless IP phone; and
The other party's wireless IP telephone receiving the notification transmits a half-duplex mode start confirmation notice to the wireless IP telephone and waits for microphone audio signal detection;
The wireless IP phone that has received the half-duplex mode start confirmation notification waits for microphone audio signal detection, and when a microphone audio signal is detected thereafter, a microphone audio signal detection start notification is sent to the partner wireless IP phone. Sending
The other party's wireless IP phone that has received the microphone audio signal detection start notification is in speaker mode, and the packet transmission control unit stops packet transmission of the upstream audio signal;
The wireless IP telephone transmits a microphone audio signal detection start notification to the other party's wireless IP telephone, then cancels the packet transmission stop of the upstream audio signal, and sequentially converts the audio signal detected from the microphone into a packet signal. The converted packet signal is transmitted to the other party's wireless IP telephone, and when the microphone voice signal is not detected, the microphone voice signal detection end notification is transmitted to the other party's wireless IP telephone and the microphone voice is transmitted. Returning to the detection waiting state;
The other party's wireless IP telephone that has received the microphone voice signal detection end notification from the wireless IP telephone returns to the microphone voice detection waiting state from the speaker mode;
The voice communication method of the wireless IP telephone system according to claim 12, further comprising: When the radio wave condition of the wireless IP telephone is improved and the delay control unit of the wireless IP telephone determines that the transmission delay amount of the delay measurement packet is reduced to a predetermined value or less and the transmission delay is recovered, The wireless IP telephone transmits a half-duplex mode release request notification to the partner wireless IP telephone;
The other party's wireless IP phone that has received the half-duplex mode release request notification transmits a half-duplex mode release request confirmation notification to the wireless IP phone to release the half-duplex mode;
The wireless IP phone that has received the transmitted half-duplex mode release request confirmation notification releases the half-duplex mode;
The voice communication method of the wireless IP telephone system according to claim 12 or 13, further comprising:   The wireless IP telephone system according to any one of claims 12 to 14, further comprising a packet transmission time adjustment step of adjusting a transmission time of the uplink voice signal packet by a packet transmission time adjustment unit. Voice communication method.   16. The method according to claim 12, further comprising the step of notifying the user that the wireless IP telephone is in the talk mode by turning on or blinking the talk mode lamp when the wireless IP telephone is in the talk mode. A voice communication method for a wireless IP telephone system according to claim 1.

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