JP2006311263A - Communication equipment and communicating method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide communication equipment and a communicating method thereof which is hardly affected by jamming and can maintain communication quality even though the jamming occurs. <P>SOLUTION: A cordless telephone system for transmitting a frame in a time division multiplex slot is provided with an error determining means 18 for determining the deterioration of a communication environment when transmitting a frame, and a frame assembling means 13 for dividing communication data in the frame to be transmitted by one slot into two parts, generating a change frame of length obtained by making the bit length of two-divided communication data double and transmitting the change frame by two slots when receiving notification from the error determining means 18. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a communication apparatus and a communication method for wireless communication using time division multiplexing.

  A communication device that communicates by TDMA (Time Division Multiple Access) is very convenient because it can transmit information at a remote location. For example, a cordless telephone device does not need to bother to go to the place where the main unit is installed to talk to the other party, and can talk while holding the child unit, so most of the telephone devices are cordless. Yes.

  However, cordless telephone devices used at home cannot be used only within a limited range because the output of radio waves is not high, and intermittent when receiving interference from microwave ovens or computers that communicate wirelessly It is often the case that the phone call is like a phone call.

  Patent Document 1 describes a communication device that can maintain communication quality even when such other interference is received.

In the mobile radio communication system described in Patent Document 1, a mobile station detects a drop in channel quality during radio communication, notifies the base station of the detected information, and the base station changes the time slot from 1 slot to 2 slots. By creating instruction information for changing and notifying the mobile station, the number of time slots used for wireless communication between the mobile station and the base station is changed to 2 slots. These two time slots are used simultaneously to transmit transmission signals to each other.
JP-A-6-244791

  However, in the mobile radio communication system described in Patent Document 1, since the same signal is inserted and transmitted in a plurality of time slots, it is established only by transmitting the same signal in a plurality of time slots. If it is disturbed by a disturbing radio wave that is generated automatically, there is a possibility of intermittent communication due to a communication error.

  If this is the case, if the communication device is a cordless telephone device, the call is continued in a state in which frame loss frequently occurs, so there is a possibility that it will be in a mute state, and the call quality cannot be maintained.

  Accordingly, an object of the present invention is to provide a communication device that is less susceptible to the influence of jamming radio waves and that can maintain communication quality.

  The communication device of the present invention, in a communication device that transmits frames in a time division multiplex slot, when transmitting the frame, when there is a notification from the detection unit to determine the deterioration of the communication environment, Of the frames transmitted in one slot, the communication data is divided into a predetermined number, a change frame is generated by multiplying the bit length of the divided communication data by the predetermined number, and the change frame is converted into the predetermined frame. Frame assembly means for transmitting in a number of slots.

  The communication apparatus of the present invention can reliably reach the communication data by setting the bit length by increasing the length of 1 bit by a predetermined number of times. Therefore, it is difficult to be affected by the interference radio wave, and the apparent S / N ratio can be improved, so that the communication distance can be extended and the communication quality can be maintained.

  The communication device of the present invention transmits, for example, a change frame with a changed bit length when the distance between the communication devices gradually increases and the communication environment deteriorates. As described above, since the operation is performed to maintain the communication state, it is possible to prevent sudden communication failure and the user can recognize the deterioration of the communication quality step by step.

  According to a first aspect of the present application, in a communication apparatus that transmits a frame in a time-division multiplexed slot, when transmitting a frame, a detection unit that determines deterioration of the communication environment, and a determination of deterioration of the communication environment from the detection unit When there is a notification to the effect that the communication data is divided into a predetermined number of frames to be transmitted in one slot, a change frame is generated by multiplying the bit length of the divided communication data by the predetermined number, Frame assembly means for transmitting the changed frame in a predetermined number of slots is provided.

  The frame assembling means divides communication data into a predetermined number of frames to be transmitted in one slot, and the bit length of the divided communication data is multiplied by the predetermined number by determining the deterioration of the communication environment from the detecting means. A change frame having a length is generated, and the change frame is transmitted in a predetermined number of slots. Therefore, it is possible to transmit the change by multiplying the length of 1 bit by the predetermined number. Accordingly, the communication time is about a predetermined number of times longer than when a frame is transmitted with a normal length of 1 bit, but the noise resistance against jamming radio waves is improved a predetermined number of times. In other words, even if the same 1-bit data is transmitted a plurality of times, it may not be possible to reach another communication device of the communication destination due to a jamming radio wave that is generated steadily, but the communication device of the present invention has a 1-bit length. By setting the length to a bit length that is a predetermined number of times longer, it is possible to reliably reach the bit length.

  The second invention of the present application is characterized in that the detecting means has a function of determining deterioration of the communication environment when a communication error becomes a predetermined value or more.

  Communication is difficult, such as when the detection means determines that the communication environment has deteriorated due to a communication error exceeding a predetermined value, and the frame cannot be synchronized and the validity of the communication data using the check code cannot be confirmed. The state can be detected.

  The third invention of the present application is characterized in that the detection means has a function of judging the deterioration of the communication environment when the received signal strength becomes a predetermined value or less.

  The detection means determines that the communication environment has deteriorated when the received signal strength is less than or equal to a predetermined value, so that even if no communication error has occurred and the communication data is normal, the communication partner device gradually leaves. If a frame to be transmitted is a change frame based on the received signal strength that becomes weaker as a result of communication, it is possible to prevent a communication error from occurring.

  A fourth invention of the present application is characterized in that the frame assembling means has a function of notifying another apparatus as a notification information of a communication command included in the change frame when transmitting the change frame. is there.

  When the frame assembling means transmits the change frame, the communication command contained in the change frame is notified to other devices as notification information, so that the communication partner device can easily determine that the frame is the change frame. Can be recognized.

  The fifth invention of the present application is characterized in that the frame assembling means has a function of notifying another apparatus as notification information of a synchronization establishment bit string included in the change frame when the change frame is transmitted. It is.

  When the frame assembling means transmits the change frame, it notifies the synchronization establishment bit string included in the change frame to other devices as notification information, so that the communication partner device can easily change the frame. I can recognize that.

  The sixth invention of the present application is characterized in that the frame assembling means has a function of changing the communication command to a changed frame compressed at a predetermined compression ratio when notifying other apparatus as a synchronization establishment bit string as notification information. It is what.

  Furthermore, when the frame assembly means notifies the synchronization establishment bit string to other devices as notification information, the bit length of the communication command is set to a length multiplied by a predetermined number, so that not only the communication data but also the communication command is obstructed. It is possible to ensure high strength against noise such as radio waves.

  According to a seventh aspect of the present application, the detection means includes a first threshold value that triggers the frame assembly means to generate a modified frame, and a second threshold value that triggers the frame assembly means to return to the original one slot. The deterioration of the communication environment is determined in step (1), and the first threshold value is larger than the second threshold value.

  As described above, when the detection unit determines the deterioration of the communication environment, it is possible to prevent frequent state transitions from the normal frame to the change frame and from the change frame to the normal frame.

  In an eighth aspect of the present invention, in a communication method of a communication device that performs frame communication in a time division multiplex slot, when a deterioration of the communication environment is detected when transmitting a frame, out of the frames transmitted in one slot The transmission data is divided into a predetermined number, a modified frame is generated by multiplying the bit length of the divided transmission data by a predetermined number, and the modified frame is transmitted in a predetermined number of slots. It is.

  When the deterioration of the communication environment is detected, the communication data is divided into a predetermined number of frames to be transmitted in one slot, and a change frame is generated by changing the bit length of the divided communication data by the predetermined number to be changed. Since the frame is transmitted in a predetermined number of slots, the length of 1 bit can be transmitted by multiplying the predetermined number. Accordingly, the communication time is about a predetermined number of times longer than when a frame is transmitted with a normal length of 1 bit, but the noise resistance against jamming radio waves is a predetermined number of times. In other words, even if the same 1-bit data is transmitted a plurality of times, it may not be possible to reach another communication device of the communication destination due to a jamming radio wave that is generated steadily, but the communication device of the present invention has a 1-bit length. By setting the length to a bit length that is a predetermined number of times longer, it is possible to reliably reach the bit length.

  The ninth invention of the present application is characterized in that the deterioration of the communication environment is determined when the communication error becomes a predetermined value or more.

  Since it is determined that the communication environment has deteriorated because the communication error has exceeded the specified value, it is necessary to detect difficult communication conditions, such as a frame that cannot be synchronized, or the validity of communication data using a check code. Can do.

  The tenth invention of the present application is characterized in that the deterioration of the communication environment is determined when the received signal strength becomes a predetermined value or less.

  Since it is determined that the communication environment has deteriorated when the received signal strength is less than or equal to the predetermined value, even if no communication error has occurred and the communication data is normal, the communication partner device gradually moves away. If a frame to be transmitted is a change frame based on the weakened received signal strength, it is possible to prevent a communication error from occurring.

  The eleventh invention of the present application is characterized in that when a change frame is transmitted, a communication command included in the change frame is notified to other devices as notification information.

  When a change frame is transmitted, the communication command included in the change frame is notified to other devices as notification information, so that the communication partner device can easily recognize that the frame is a change frame. it can.

  The twelfth invention of the present application is characterized in that when a change frame is transmitted, a synchronization establishment bit string included in the change frame is notified to other devices as notification information.

  When transmitting a change frame, the synchronization establishment bit string included in the change frame is notified to other devices as notification information, so that the communication partner device can easily recognize that the frame is a change frame. Can do.

  The thirteenth invention of the present application is characterized in that when a synchronization establishment bit string is notified to other devices as notification information, the bit length of the communication command is a changed frame multiplied by a predetermined number. is there.

  In addition, when the synchronization establishment bit string is notified to other devices as notification information, the bit length of the communication command is multiplied by a predetermined number. It is possible to ensure a high strength against.

  According to a fourteenth aspect of the present application, the deterioration of the communication environment is determined based on a first threshold value that triggers generation of a modified frame and a second threshold value that triggers return to the original one slot. The threshold value is a value larger than the second threshold value.

  By determining the deterioration of the communication environment in this way, it is possible to prevent frequent state transitions from a normal frame to a changed frame and from a changed frame to a normal frame.

(Embodiment)
A communication device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 6, taking a cordless telephone device as an example. FIG. 1 is a diagram illustrating a cordless telephone device that is an example of a communication device according to an embodiment of the present invention. FIG. 2 is a diagram for explaining a configuration of a parent device that is an example of a communication device according to an embodiment of the present invention. FIG. 3 is a diagram for explaining the configuration of a frame used when the cordless telephone apparatus according to the embodiment of the present invention communicates. FIG. 4 is a diagram illustrating an example of a communication command used when the cordless telephone apparatus according to the embodiment of the present invention transmits a change frame. FIG. 5 is a flowchart for explaining the operation of the cordless telephone apparatus according to the embodiment of the present invention. 6A and 6B are diagrams for explaining a frame of the cordless telephone apparatus according to the embodiment of the present invention.

  First, the configuration of a cordless telephone apparatus as a communication apparatus according to an embodiment of the present invention will be described with reference to FIG. As shown in FIG. 1, a cordless telephone device 1 that is an example of a communication device according to an embodiment of the present invention includes a parent device 2 and three child devices 3. Base unit 2 and handset 3 communicate with each other by TDMA. The base unit 2 is connected to the telephone line 4, and the handset 3 communicates with the base unit 2 to make a call via the telephone line 4. In FIG. 1, three slave units 3 are shown, but one or four or more slave units 3 may be used. Further, the functions of the communication device according to the embodiment of the present invention are mounted on the parent device 2 and the child device 3, but in this embodiment, the configuration and operation of the parent device 2 will be described.

  Next, the structure of the main | base station 2 which concerns on embodiment of this invention is demonstrated based on FIG. Base unit 2 includes microphone 10, voice encoding means 11, transmission voice data buffer 12, frame assembling means 13, digital modulation means 14, wireless means 15, digital demodulation means 16, and synchronization bit comparison means. 17, error determination means 18, error slot determination means 19, frame decomposition means 20, control data buffer 21, received voice data buffer 22, registration information storage means 23, voice decoding means 24, speaker 25.

  The microphone 10 converts the sound into an analog electric signal and outputs it to the sound encoding means 11.

  The voice encoding means 11 converts the voice electric signal into a digital signal and compresses it to output it to the transmission voice data buffer 12 as compressed voice data.

  The transmission audio data buffer 12 temporarily stores the compressed audio data compressed by the audio encoding unit 11.

  The frame assembling unit 13 generates transmission data based on the determination by the error slot determination unit 19 and outputs the transmission data to the digital modulation unit 14. The frame assembling means 13 halves the data rate when the error is greater than or equal to the first threshold value as determined by the error slot determining means 19. That is, among the frames transmitted in one slot, the compressed audio data, which is transmission data, is divided into two, and a modified frame in which the bit length of the divided transmission data is doubled is generated. If the error is less than or equal to the second threshold value as determined by the error slot determining means 19, the frame returned to the original one slot is restored.

  The digital modulation means 14 performs digital modulation according to the output of the frame assembly means 13 and outputs the result to the wireless means 15.

  The radio unit 15 converts the output of the digital modulation unit 14 into an RF (Radio Frequency) signal and sends it into the air. Further, it receives the RF signal of the communication partner, converts the frequency into a baseband signal, and outputs it to the digital demodulation means 16.

  The digital demodulating means 16 receives the output signal of the wireless means 15, performs digital demodulation, and outputs it to the synchronization bit comparing means 17 and the frame decomposing means 20.

  The synchronization bit comparison unit 17 detects a synchronization bit from the output of the digital demodulation unit 16. When a synchronization bit is detected, a synchronization signal is generated from this synchronization bit and output to the error determination means 18.

  The error determination means 18 performs error determination when the next synchronization signal cannot be obtained within a fixed period of the TDMA communication cycle from the synchronization signal, and notifies the error slot determination means 19 of error determination when an error is detected.

  The error slot determination unit 19 notifies the reception audio data buffer 22 when there is an error determination of the error determination unit 18. The error slot determination unit 19 refers to the communication destination information registered in the registration information storage unit 23 when the error determination unit 18 has made an error determination and the reception level is a predetermined level or less. If the other party is a communication apparatus that can handle the changed frame, the frame assembling means 13 is notified of this.

  The frame decomposing means 20 decomposes the output of the digital demodulating means 16 into frames, outputs communication commands to the control data buffer 21, and outputs received audio data to the received audio data buffer 22.

  The control data buffer 21 buffers communication commands in the frame.

  The reception audio data buffer 22 buffers the reception audio data decomposed by the frame decomposition means 20.

  The registration information storage means 23 takes out information of the communication partner from the control data buffer 21 and stores it at the time of wireless registration.

  The voice decoding unit 24 decodes the voice from the communication data of the received voice data buffer 22 based on the communication command (notification information) of the changed frame stored in the control data buffer 21 and outputs an analog signal.

  The speaker 25 outputs the analog signal from the voice decoding unit 24 as sound.

  The configuration of the frame transmitted and received by the cordless telephone apparatus 1 according to the embodiment of the present invention configured as described above will be described in detail with reference to FIGS.

  As shown in FIG. 3, the frame configuration is composed of four transmission slots and four reception slots following the four transmission slots.

  In one slot, a 16-bit ramp bit, a 16-bit preamble, a 16-bit SYNC, a 64-bit A field, a 320-bit B field, a 4-bit X field, and a 4-bit Z field And is used for transmission and reception.

  The ramp bit is used for determining the sample bit, and is fixed data of “1010 1010 1010 1010”. The preamble is fixed data “1010 1010 1010 1010” in a frame transmitted from the parent device 2 to the child device 3, and “0101 0101 0101 0101” in a frame transmitted from the child device 3 to the parent device 2. Fixed data.

  SYNC is a synchronization establishment bit string used for frame synchronization establishment. The frame transmitted from the parent device 2 to the child device 3 has fixed data “1110 1001 1000 1010”, and the frame transmitted from the child device 3 to the parent device 2 has fixed data “0001 0110 0111 0101”. .

  The A field is composed of an 8-bit header part, a 40-bit tail part, and a 16-bit CRC, and a communication command is stored in the header part and the tail part. For example, when the parent device 2 notifies the child device 3 of an incoming call or notifies the parent device 2 of a call request from the child device 3, a communication command corresponding to the state is stored. In the change frame, a communication command indicating that this frame is a change frame is stored in the header part and the tail part. As shown in FIG. 4, in the present embodiment, when a change frame is transmitted, when a request is made from the child device 3 to the parent device 2, “0000 0001” is stored in the header portion, and the upper 8 bits of the tail portion Stores “0000 0010”. As a response of the base unit 2 to the request, “1000 0000” is stored in the header portion, and “0000 0010” is stored in the upper 8 bits of the tail portion.

  Returning to FIG. 3, 320 bits of audio data are stored in the B field. For example, call data from the parent device 2 to the child device 3 or from the child device 3 to the parent device 2 is stored. In the B field, if a communication command indicating that the frame is changed in the A field is stored, each bit of 160 bits of data out of 320 bits of data is stored with a 2-bit length.

  In the X field, CRC which is a check code of the B field is stored in 4 bits, and in the Z field, CRC from the A field to the X field is stored in 4 bits.

  The operation of the cordless telephone apparatus 1 according to the embodiment of the present invention that performs communication using the frame configured as described above will be further described with reference to FIGS.

  First, the base unit 2 of the cordless telephone device 1 communicates with the handset 3 in a normal operation (S10). The base unit 2 uses the error determination unit 18 to determine a frame that is transmitted in the transmission slot of the handset 3 and has a communication error in which synchronization cannot be established because a ramp bit or preamble cannot be received. Then, it is counted for a certain period, and it is determined whether or not the number of communication errors is greater than or equal to a threshold A (first threshold) (S20).

  If the number of communication errors is less than the threshold value A in S20, the base unit 2 proceeds to S10 and continues communication with the handset 3 in the normal state.

  When the number of communication errors is greater than or equal to threshold A in S20, base unit 2 has a received signal strength (RSSI: Received Signal Strength Indicator) of the received frame equal to or less than threshold B (second threshold). Whether or not the error slot determination means 19 determines whether or not, from the wireless means 15 (S30).

  If the RSSI is larger than the threshold value B in S30, the parent device 2 moves to S10 and continues communication with the child device 3 in the normal state.

  If the RSSI is equal to or less than the threshold value B in S30, the error slot determination means 19 refers to the communication destination information registered in the registration information storage means 23, and the communication apparatus that can correspond to the changed frame by the other party of the communication destination It is determined whether or not. In this case, since the slave unit 3 is compatible, the error slot determination unit 19 notifies the frame assembly unit 13 of the fact. The frame assembling means 13 divides transmission data into two of the frames transmitted in one slot and generates a modified frame in which the bit length of the divided transmission data is doubled. Then, the digital modulation means 14 performs digital modulation according to the output of the frame assembly means 13 and outputs the result to the slave unit 3 via the wireless means 15. This will be described with reference to FIGS. 6 (A) and 6 (B). FIG. 6A shows a frame configuration of the transmission side communication apparatus, and FIG. 6B shows a frame configuration of the reception side communication apparatus. That is, as shown in FIGS. 6A and 6B, in the normal frame, transmission data is transmitted from the parent device 2 to the child device 3 in one slot. However, by changing to a changed frame along with the deterioration of the communication environment, what was transmitted in one slot is transmitted using two slots (S40).

  When communication is performed with a change frame from the parent device 2 to the child device 3 or from the child device 3 to the parent device 2, the error determination means 18 counts a frame of a communication error that cannot be established synchronously for a certain period. Then, it is determined whether or not it is equal to or less than the threshold value C (second threshold value) (S50).

  If there are more communication error frames than the threshold C in S50, the process proceeds to S40 and communication with the changed frame is continued.

  When the communication error frame is equal to or smaller than the threshold C in S50, the base unit 2 determines whether or not the RSSI of the received frame is equal to or larger than the threshold D (S60).

  If the RSSI of the received frame is smaller than the threshold value D in S60, the base unit 2 proceeds to S40 and continues communication with the changed frame.

  If it is equal to or greater than the threshold value D in S60, the process proceeds to S10 and returns to a normal state in which communication is performed using a frame having a normal bit length.

  The threshold value A and the threshold value C, which are the number of determinations of the frequency of occurrence of communication errors, are set to a larger value. In other words, the transition from the normal bit length frame to the change frame of the double bit length frame is performed by detecting the occurrence of the communication error count greater than or equal to the threshold A, but the return is not greater than the threshold C. This is done by detecting. This is because if the state transition is based only on the threshold A, the state transition frequently occurs due to a change in the communication environment. Accordingly, the return is set to be equal to or less than the threshold value C, and the threshold value A is set to a value larger than the threshold value C, thereby providing a hysteresis characteristic.

  When receiving the change frame, the slave unit 3 analyzes the communication command of the A field and, when recognizing that it is the change frame, analyzes the communication data of the B field with a 2-bit length and transmits the next frame to be transmitted. The communication data is combined into a normal frame.

  In this way, when the communication environment deteriorates, the communication data is divided into two in a frame transmitted in one slot, and a change frame in which the bit length of the divided call data is doubled is generated. Since transmission is performed in two slots, transmission can be performed with a bit length that is twice the length of one bit. Accordingly, the communication time is twice as long as when a frame is transmitted with a normal length of 1 bit, but the noise resistance against jamming waves is twice as long. That is, even if the same 1-bit data is transmitted twice, it may not be possible to reach the other communication device of the communication destination due to the disturbing radio waves that are generated steadily, but the cordless telephone device 1 according to the present embodiment In this case, the bit length can be reliably reached by setting the bit length by double the length of one bit length.

  Next, a cordless telephone apparatus according to another embodiment of the present invention will be described with reference to FIG. FIG. 7 is a diagram showing an example of a synchronization establishment bit string used when a cordless telephone apparatus according to another embodiment of the present invention transmits a change frame. The cordless telephone device 1 according to another embodiment of the present invention is characterized in that a change frame is notified to another communication device using a synchronization establishment bit string (notification information).

  As shown in FIG. 7, when transmitting a normal frame, SYNC, which is a synchronization establishment bit string used for establishing frame synchronization, is “1110 1001 1000 1010” in a frame transmitted from the parent device 2 to the child device 3. Yes, the frame transmitted from the child device 3 to the parent device 2 is “0001 0110 0111 0101”.

  However, when the communication environment deteriorates, the changed frame is transmitted with a length that doubles the 1-bit length. In that case, this SYNC is used to notify the communication destination that it is a changed frame.

  For example, “1000 1010 1110 1001” is used for a frame transmitted from the parent device 2 to the child device 3, and “0111 0101 0001 0110” is used for a frame transmitted from the child device 3 to the parent device 2.

  By changing the SYNC in this way, this changed frame doubles not only the voice data as communication data stored in the B field but also the fields below the SYNC, the A field, the B field, the X field, and the Z field. Therefore, it is possible to further improve the strength against noise such as jamming radio waves.

  It should be noted that this synchronization establishment bit string of SYNC can be appropriately set as long as it is negotiated between the parent device 2 and the child device 3.

  The embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments. For example, the bit length of one bit may be three times, four times, or more. it can. In that case, the transmission frame is transmitted by three, four, or a number of change frames corresponding to multiples thereof.

  The present invention is suitable for a communication apparatus and a communication method for performing wireless communication by time division multiplexing because it is difficult to be affected by the occurrence of jamming waves and can maintain communication quality.

The figure explaining the cordless telephone apparatus which is an example of the communication apparatus which concerns on embodiment of this invention The figure explaining the structure of the main | base station which is an example of the communication apparatus which concerns on embodiment of this invention The figure explaining the structure of the flame | frame used when the cordless telephone apparatus which concerns on embodiment of this invention communicates The figure which shows an example of the communication command used when the cordless telephone apparatus which concerns on embodiment of this invention transmits a change frame. The flowchart explaining operation | movement of the cordless telephone apparatus which concerns on embodiment of this invention. (A) The figure explaining the frame of the cordless telephone apparatus which concerns on embodiment of this invention, (B) The figure explaining the frame of the cordless telephone apparatus which concerns on embodiment of this invention The figure which shows an example of the synchronization establishment bit sequence used when the cordless telephone apparatus which concerns on other embodiment of this invention transmits a change frame.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cordless telephone apparatus 2 Parent | base station 3 Slave | mobile_unit 4 Telephone line 10 Microphone 11 Voice coding means 12 Transmission voice data buffer 13 Frame assembly means 14 Digital modulation means 15 Radio means 16 Digital demodulation means 17 Synchronous bit comparison means 18 Error judgment means 19 Error slot determination means 20 Frame decomposition means 21 Control data buffer 22 Received voice data buffer 23 Registration information storage means 24 Voice decoding means 25 Speaker

Claims (14)

In a communication device that transmits frames in a time division multiplexed slot,
Detecting means for determining deterioration of the communication environment when transmitting the frame;
When there is a notification from the detection means that the deterioration of the communication environment has been determined, the communication data of the frame transmitted in one slot is divided into a predetermined number, and the bit length of the divided communication data is set to the predetermined value. A communication apparatus comprising: a frame assembling unit that generates a modified frame having a length multiplied by a number and transmits the modified frame in the predetermined number of slots. The communication device according to claim 1, wherein the detection unit has a function of determining deterioration of the communication environment when a communication error becomes a predetermined value or more. The communication device according to claim 1, wherein the detection unit has a function of determining deterioration of the communication environment based on a received signal strength being a predetermined value or less. 4. The frame assembly means according to claim 1, further comprising a function of notifying another device of a communication command included in the change frame as notification information when the change frame is transmitted. The communication device according to the section. 4. The frame assembly means according to claim 1, further comprising a function of notifying another apparatus as notification information of a synchronization establishment bit string included in the change frame when the change frame is transmitted. A communication device according to any of the above sections. The frame assembling means has a function of setting a change frame in which the bit length of the communication command is multiplied by the predetermined number when the synchronization establishment bit string is notified to another device as notification information. The communication device according to claim 5, wherein: The detection means includes a first threshold value that triggers the frame assembly means to generate the changed frame, and a second threshold value that triggers the frame assembly means to return to the original one slot. Determine deterioration,
The communication apparatus according to claim 1, wherein the first threshold value is a value larger than the second threshold value. In a communication method of a communication device that performs frame communication in a time division multiplexed slot,
When detecting degradation of the communication environment when transmitting the frame,
The transmission data is divided into a predetermined number of the frames to be transmitted in one slot, and a change frame having a bit length of the divided transmission data multiplied by the predetermined number is generated,
A communication method of a communication apparatus, wherein the change frame is transmitted in the predetermined number of slots. 9. The communication method of a communication apparatus according to claim 8, wherein the deterioration of the communication environment is determined when a communication error becomes a predetermined value or more. 10. The communication method of a communication apparatus according to claim 8, wherein the deterioration of the communication environment is determined when a received signal strength becomes a predetermined value or less. 11. The communication method of a communication apparatus according to claim 8, wherein when the change frame is transmitted, a communication command included in the change frame is notified to other apparatuses as notification information. . 11. The communication of a communication device according to claim 8, wherein when transmitting the change frame, the synchronization establishment bit string included in the change frame is notified to other devices as notification information. Method. 13. The communication apparatus according to claim 12, wherein when the synchronization establishment bit string is notified as notification information to another apparatus, a change frame in which a bit length of the communication command is multiplied by the predetermined number is used. Communication method. Determining degradation of the communication environment with a first threshold that triggers the generation of the modified frame and a second threshold that triggers a return to the original one slot,
The communication method of the communication apparatus according to claim 8, wherein the first threshold value is larger than the second threshold value.

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