Communication device, communication method

Abstract

To provide a communication device or the like that prevents trouble due to slot switching.SOLUTION: In a communication device 10, a receiving unit 24 alternately receives in a first slot or a second slot according to a time-division multiple access method. An audio signal decoding unit 20 decodes an audio signal of either a first received signal or a second received signal. A recording device 14 records the first received signal or the second received signal. A baseband signal processing unit 19 determines priority from information included in the first received signal and the second received signal, and outputs information about the priority. A control unit 18 switches an audio output target to the second slot and causes the recording device 14 to start recording the first received signal when the second received signal having a higher priority than the first received signal is received after the first received signal is received in the first slot.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a communication device.

Background Art

[0002] In a wireless communication technology called DMR (Digital Mobile Radio), the time-division multiple access (TDMA (Time Division Multiple Access)) method is used to enable two independent communication accesses (for example, a first slot and a second slot) simultaneously. By using this, when a communication device in a call using one slot receives a signal in the other slot, it becomes possible to switch the slot for the call.

[0003] For example, a wireless communication system is disclosed in which a wireless terminal selects one of a plurality of repeaters connected by a communication line when communicating with another wireless terminal (Patent Document 1). This wireless terminal analyzes whether its own terminal exists at the destination of the call information when there is call information in the communication information, determines whether the priority of the call information is higher than that of the current call if it exists, and changes to another repeater channel of the call information when it is higher.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when a communication device compliant with the DMR system receives a signal with a higher priority in the second slot while outputting the voice of the signal received in the first slot, the voice to be output is switched from the first slot to the second slot. Therefore, the user of this communication device will miss the voice in the first slot midway. Also, the communication partner who was speaking to this communication device via the first slot cannot know that the slot has been switched midway.

[0006] The present invention has been made to solve such problems, and an object thereof is to provide a communication device and the like that suppresses problems caused by slot switching.

Means for Solving the Problems

[0007] The communication device according to the present invention includes a reception circuit, a voice signal decoding circuit, a recording device, and a control circuit. The reception circuit receives in the first slot or the second slot by a time division multiple access method. The voice signal decoding circuit decodes a voice signal with either the first received signal or the second received signal received as the target of voice output. The recording device is set to be able to record at least the voice signal of at least either the first received signal or the second received signal. The baseband signal processing circuit determines the priority from the information included in the first received signal and the second received signal, and outputs information regarding the priority. When the control circuit receives the second received signal with a higher priority than the first received signal after receiving the first received signal in the first slot, the control circuit switches the target of voice output from the first slot of the first received signal to the second slot of the second received signal, and starts recording of at least the signal corresponding to the voice signal in the first received signal in the recording device.

Effects of the Invention

[0008] According to the present invention, it is possible to provide a communication device and the like that suppresses problems caused by slot switching.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

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Figure 10

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Figure 14

Figure 15

Figure 16

Mode for Carrying Out the Invention

[0010] Hereinafter, the present invention will be described through embodiments of the invention. However, the invention according to the claims is not limited to the following embodiments. Also, not all of the configurations described in the embodiments are necessarily essential as means for solving the problems. For the sake of clarity of explanation, the following description and drawings have been appropriately omitted and simplified. In each drawing, the same reference numerals are assigned to the same elements, and redundant explanations are omitted as necessary.

[0011] <Embodiment 1> Hereinafter, embodiments of the present invention will be described with reference to the drawings. Referring to FIG. 1, a communication device according to an embodiment will be described. FIG. 1 is a configuration block diagram of a communication device 10 according to an embodiment. The communication device 10 is an embodiment of a communication device. The communication device 10 is a radio that transmits and receives frequency-modulated signals and complies with the DMR (Digital Mobile Radio) standard. DMR is a communication standard defined by the European Telecommunications Standards Institute (ETSI).

[0012] The main components of the communication device 10 include a recording device 14, a control unit 18, a baseband signal processing unit 19, a voice signal decoding unit 20, a voice signal processing unit 21, and a transmission / reception unit 22 (transmission unit 23, reception unit 24). In addition to the above-described configuration, the communication device 10 also includes a display unit 11, an operation unit 12, a peripheral unit 13, a speaker 15, a microphone 16, an antenna 17, and an RF switch unit 25.

[0013] The recording device 14 includes a non-volatile memory such as a flash memory, for example. The recording device 14 is set to be able to record at least the voice signal of at least one of the first received signal and the second received signal. The recording device 14 may be built into the communication device 10 or may be configured to be detachable from the communication device 10.

[0014] The control unit 18 is also referred to as a control circuit. Some or all of its components may be implemented by general-purpose or dedicated circuitry, processors, etc., or combinations thereof. These may be constituted by a single chip or by a plurality of chips connected via a bus. More specifically, the control unit 18 includes, for example, a CPU (Central Processing Unit) or an MCU (Micro Controller Unit).

[0015] The control unit 18 receives various signals from each component of the communication device 10 and controls each component according to the received signals. For example, the control unit 18 receives a predetermined operation from the operation unit 12 and causes the communication device 10 to exhibit its functions according to the received operation. At this time, the control unit 18 can exchange signals with the baseband signal processing unit 19 and the audio signal processing unit 21 in order to realize the functions according to this embodiment. Also, for example, when the communication device 10 receives a received signal, the control unit 18 receives the accompanying information included in this signal from the baseband signal processing unit 19 and processes the received information. That is, for example, when the accompanying information of the received signal includes a message to be displayed, this message is displayed on the display unit 11.

[0016] Also, the control unit 18 executes processing for each of the first slot and the second slot compliant with DMR. More specifically, for example, when the control unit 18 receives a first received signal in the first slot and no signal is received in the second slot, the control unit 18 reads the accompanying information included in the first received signal and supplies the read accompanying information to the control unit 18. Further, the control unit 18 supplies the audio signal included in the first received signal to the audio signal decoder 20 for the purpose of outputting it from the speaker 15.

[0017] After the control unit 18 receives the first received signal in the first slot, when it receives a second received signal with a higher priority than the first received signal in the second slot, it switches the target of the voice output from the first slot of the first received signal to the second slot of the second received signal. In this case, the control unit 18 continues to detect the first received signal and starts the recording device to record at least the signal corresponding to the voice signal among the first received signals.

[0018] The baseband signal processing unit 19 is a circuit block including, for example, a DSP (Digital Signal Processor), and may be referred to as a baseband signal processing circuit. The baseband signal processing unit 19 can mutually exchange signals with the control unit 18 and the voice signal processing unit 21 to realize the functions according to the present embodiment. The baseband signal processing unit 19 receives the received signal received by the communication device 10 via the transmission unit 23 and reads the information included in the received signal.

[0019] More specifically, for example, the baseband signal processing unit 19 reads the first received signal in the first slot and the second received signal in the second slot compliant with DMR, respectively, and determines the priority from the information included in the first received signal and the second received signal. The baseband signal processing unit 19 supplies the information regarding the determined priority to the control unit 18. As the information included in the received signal, there are those indicating that the type of the signal is related to the form of calls such as individual calls and group calls, and those indicating that it is a special call (for example, an emergency call). The priority order needs to be set in advance when operating the wireless communication system using this communication device. Also, the information included in the received signal may include information indicating the priority. The present embodiment is a technology focusing on the priority determined from the information included in the received signal. Therefore, in the following description, there may be expressions such as reading the priority included in the received signal.

[0020] For example, the baseband signal processing unit 19 supplies a predetermined received signal to the voice signal decoding unit 20 for the purpose of outputting voice to the speaker 15. In this case, the baseband signal processing unit 19 receives the voice signal decoded by the voice signal decoding unit 20. Further, the baseband signal processing unit 19 supplies the received voice signal to the speaker 15 via the voice signal processing unit 21. Thereby, the speaker 15 outputs the voice signal included in the received signal.

[0021] The voice signal decoding unit 20 is also referred to as a voice signal decoding circuit or a vocoder. The voice signal decoding unit 20 decodes a voice signal using either the received first received signal or the second received signal as the target of voice output. The voice signal decoding unit 20 receives the received signal from the baseband signal processing unit 19 and decodes it. Then, the voice signal decoding unit 20 supplies the decoded voice signal to the baseband signal processing unit 19.

[0022] The voice signal processing unit 21 is also referred to as a voice signal processing circuit. The voice signal processing unit 21 can mutually exchange signals with the baseband signal processing unit 19 and the control unit 18 in order to realize the functions according to the present embodiment. The voice signal processing unit 21 performs A / D conversion (Analog to Digital conversion) on the voice signal received from the microphone 16, generates a modulated wave by performing various processes such as band limitation, and supplies it to the transmission / reception unit 22. Also, the voice signal processing unit 21 performs D / A conversion (Digital to Analog conversion) on the voice signal received from the voice signal decoding unit 20, and supplies the voice signal generated by demodulation and decoding to the speaker 15.

[0023] The transmission / reception unit 22 is a circuit block including a transmission unit 23 and a reception unit 24. The transmission / reception unit 22 transmits data to other wireless devices in a half-duplex communication method. The transmission / reception unit 22 receives data transmitted by other wireless devices in a half-duplex communication method. The other wireless device may operate as a relay station.

[0024] When the transceiver unit 22 receives a signal via the antenna 17 and the RF switch unit 25, it supplies the received signal (received signal) to the voice signal processing unit 21. Also, when the transceiver unit 22 receives a signal (transmission signal) to be transmitted to another radio device from the voice signal processing unit 21, it outputs the received transmission signal to the antenna 17 via the RF switch unit 25. The RF switch unit 25 is also referred to as a high-frequency switch. The RF switch unit 25 appropriately switches the path of the received signal and the path of the transmission signal respectively.

[0025] The receiving unit 24 is also referred to as a receiving circuit. The receiving unit 24 alternately receives the first received signal received in the first slot and the second received signal received in the second slot by a time-division multiple access method.

[0026] The transmitting unit 23 is also referred to as a transmitting circuit. The transmitting unit 23 transmits a transmission signal corresponding to the first slot or the second slot by a time-division multiple access method and half-duplex communication.

[0027] The display unit 11 is a display device including a liquid crystal panel and displays various information. The display unit 11 receives an instruction regarding the content displayed by the display unit 11 from the control unit 18. The display unit 11 can display, for example, information regarding the communication partner during reception. The communication device 10 may receive signals in both the first slot and the second slot, and in some cases, output the voice of one of the slots from the speaker and record the voice of the other slot in the recording device without outputting it from the speaker. In this case, the display unit 11 may display, for example, "Back slot busy" as a display indicating that it is receiving the signal of the slot other than the slot from which the voice is being output. Here, "Back slot busy" indicates that the slot from which the voice is being output is the front, and the slot from which the voice is not being output is the back (Back), meaning that the back slot is also being received.

[0028] The operation unit 12 is a user interface such as operation keys provided for the communication device 10 to realize its functions. The operation unit 12 includes, for example, a PTT switch.

[0029] The PTT switch is an operation unit for realizing half-duplex communication by push-to-talk. For example, when the user speaks and transmits an audio signal, the user presses the PTT switch. The control unit 18 sets the communication device 10 to the reception standby state when the PTT switch is not pressed, and sets the communication device 10 to the transmission state when the PTT switch is pressed.

[0030] The peripheral unit 13 may include, for example, an interface with an external connection device such as earphones or a USB (Universal Serial Bus) terminal, and a user interface such as an LED (light-emitting diode) or a buzzer.

[0031] Next, the functional configuration of the communication device 10 will be described with reference to FIG. 2. FIG. 2 is a functional block diagram of the communication device 10 according to Embodiment 1. FIG. 2 shows, among the functions of the communication device 10, in particular, the function of the communication device 10 for recording an audio signal from a received signal. The signal processing block 100 shown in the figure indicates the functions realized by the components of the communication device 10, and there is not necessarily a physical correspondence with the configuration shown in FIG. 1. The signal processing block 100 may be realized by a plurality of components shown in FIG. 1 being related to each other. Alternatively, the signal processing block 100 may indicate a part of the functions of the control unit 18 or the like.

[0032] The communication device 10 shown in FIG. 2 includes a digital signal detection unit 101, a chapter generation unit 102, a received audio conversion unit 104, a recorded data generation unit 105, a recorded audio control unit 106, an audio signal extraction unit 107, an attached information extraction unit 108, a PTT operation detection unit 109, an audio output control unit 110, and a display control unit 111 in the signal processing block 100. The signal processing block 100 is also communicably connected to the display unit 11, the recording device 14, the speaker 15, the baseband signal processing unit 19, the transceiver unit 22, the PTT switch 26, and the non-volatile memory 27, respectively.

[0033] The digital signal detection unit 101 of the signal processing block 100 reads the received signal and supplies information about the counterpart station of the reception source to the chapter generation unit 102. The information about the counterpart station may include, for example, the frequency of the received signal, the ID (identification, identifier) of the counterpart station, the priority of the received signal, whether the received slot is the first slot or the second slot, and the reception start time, etc. When the chapter generation unit 102 receives the above information, it appropriately supplies these received information to the recording data generation unit 105. Also, the received voice conversion unit 104 performs A / D conversion on the received voice signal and supplies the converted data to the recording data generation unit 105.

[0034] Next, the recording data generation unit 105 synthesizes the voice signal and the information about the counterpart station to generate recording data. The recording data generation unit 105 supplies the generated recording data to the recorded voice control unit 106. Further, the recorded voice control unit 106 executes a process of writing the recording data to the recording device 14.

[0035] When playing back the recorded voice, the recorded voice control unit 106 reads data from the recording device 14 and supplies the read data to each of the voice signal extraction unit 107 and the accompanying information extraction unit 108. The voice signal extraction unit 107 extracts the voice signal included in the recording data and supplies the extracted voice signal to the voice output control unit 110. The voice output control unit 110 causes the received voice signal to be output from the speaker 15.

[0036] On the other hand, the accompanying information extraction unit 108 extracts accompanying information such as information about the counterpart station included in the recording data, and supplies predetermined information to be displayed on the display unit 11 among the extracted accompanying information to the display control unit 111. The display control unit 111 receives the predetermined accompanying information from the accompanying information extraction unit 108 and causes this to be displayed on the display unit 11.

[0037] Next, the processing when the PTT switch is pressed while the recorded voice signal is being played back will be described. When the PTT switch 26 is pressed while the communication device 10 is outputting the voice signal related to the recorded data from the speaker 15 (i.e., playing back the recorded voice), the communication device 10 can transmit a signal (i.e., perform a talk-back) to the other party related to the voice being played back. That is, for example, when the user of the communication device 10 presses the PTT switch 26, the signal processing block 100 acquires the ID of the other party from the accompanying information of the voice signal being played back, and performs transmission using the acquired ID. Thereby, even after the reception of the signal from the other party is completed, the communication device 10 can transmit a signal to the other party that is playing back the voice signal.

[0038] Note that the non-volatile memory 27 is, for example, a memory included in the control unit 18, and stores, for example, a computer program (hereinafter also simply referred to as a program) for executing the communication method according to the present embodiment. The control unit 18 causes the recording device 14 to read the program into the random access memory and executes this program.

[0039] Next, an example of a communication system including the communication device 10 will be described with reference to FIG. 3. FIG. 3 is a schematic configuration diagram of a communication system including the communication device 10 according to Embodiment 1. FIG. 3 shows a terminal A, a terminal B, a terminal C, and a repeater, which are the communication devices 10. The terminals A, B, and C each perform transmission and reception of signals conforming to the DMR standard. The repeater is a relay device that relays the signals of the terminals A, B, and C. In FIG. 3, the strip-shaped rectangles and arrows shown between the terminals A, B, and C and the repeater indicate the images of the signals transmitted and received by the respective terminals.

[0040] In the above configuration, the terminal B starts transmitting a signal using the first slot out of the first slot and the second slot. At this time, the terminal A receives the signal of the first slot transmitted by the terminal B via the repeater.

[0041] On the one hand, the terminal C starts transmitting a signal using the second slot out of the first slot and the second slot. At this time, the terminal A receives the signal of the second slot transmitted by the terminal C via the repeater.

[0042] As described above, the terminal A can receive both the signal of the first slot transmitted by the terminal B and the signal of the second slot transmitted by the terminal C. Note that when transmitting a signal, the terminal B can set a priority. Similarly, the terminal C can set a priority when transmitting a signal. Here, in the example shown in FIG. 3, it is assumed that the priority of the signal transmitted by the terminal C is higher than the priority of the signal transmitted by the terminal B. In this case, regardless of the order of arrival of the signals, the terminal A outputs the voice signal of the terminal C from the speaker. Regarding the setting of the priority, it may be directly settable. However, as described above, when the priority order is set in advance on the receiving side in the form of a call, selecting a call form with a higher priority is also included in setting the priority.

[0043] Next, the outline of the frame configuration of the DMR transmission and reception signals will be described with reference to FIG. 4. FIG. 4 is a diagram for explaining the frame structure of the transmission and reception signals according to the first embodiment. FIG. 4 shows the transmission signal (BS TX) of the base station on the upper side and the transmission signal (MS TX) of the mobile station on the lower side.

[0044] The transmission signals of the base station shown on the upper side of FIG. 4 are configured by alternating the first slot and the second slot. The transmission signals of the base station define a combination of the first slot and the second slot as one frame, and the transmission period of each of the first slot and the second slot is 30 milliseconds, and the transmission period for one frame combined is set to 60 milliseconds. Each slot also includes a 108-bit payload and a 48-bit sync (SYNC) or embedded signaling. The payload includes an audio signal. Note that the transmission signals of the base station are set to transmit a 24-bit CACH signal (Common Announcement Channel) indicating the usage status of each slot during a 2.5-millisecond period adjacent to each of the first slot and the second slot.

[0045] The transmission signals of the mobile station shown on the lower side of FIG. 4 are also configured by alternating the first slot and the second slot. The transmission signals of the mobile station define a combination of the first slot and the second slot as one frame, and the transmission period of each of the first slot and the second slot is 30 milliseconds, and the transmission period for one frame combined is set to 60 milliseconds. Each slot also includes a 108-bit payload and a 48-bit sync (SYNC) or embedded signaling. Note that the transmission signals of the mobile station do not include signals during a 2.5-millisecond period adjacent to each of the first slot and the second slot.

[0046] Next, with reference to FIG. 5, the list chunk format in the communication device 10 will be described. FIG. 5 is a diagram showing an example of the list chunk format in the communication device 10 according to Embodiment 1.

[0047] The list chunk format according to this embodiment is composed of four elements: "Chunk ID", "Chunk Data Size", "Type ID", and "List of Text Labels and Name". "Chunk ID" is fixed as the string "LIST". "Chunk Data Size" indicates the size of the data part, which is the sum of all sub-chunks + 4 bytes. "List of Text Labels and Name" indicates the content of the actual data.

[0048] Next, referring to FIG. 6, the data included in the list chunk will be described. FIG. 6 is a diagram for explaining the data included in the list chunk. The data included in the list chunk includes "Chapter Address" and "Unit ID". The data size of both "Chapter Address" and "Unit ID" is 4 bytes. "Chapter Address" indicates the start position of the audio data. "Unit ID" stores the ID of the received wireless terminal.

[0049] Next, referring to FIG. 7, a specific example of the list chunk will be described. FIG. 7 is a diagram showing an example of the list chunk of the system according to Embodiment 1. The data of the list chunk shown in FIG. 7 is shown in a state where the signal is separated every 4 bytes.

[0050] The first data C11 has "list" set as the chunk ID. The second data C12 has "00 00 00 18" set as the chunk data size. That is, in the example shown here, the data size is set to 24 bytes (0x18). The third data C13 has "adtl" set as the "Type ID". The fourth data C14 has "00 40 00 00" set as the address. The next data C15 has "00 00 00 01" set as the peer ID.

[0051] Next, with reference to FIG. 8, a specific example of a list chunk will be described. FIG. 8 shows a method for reading a list chunk executed by the communication device 10.

[0052] When the communication device 10 receives a signal from any other communication device, it reads the signal and determines whether the read data is list chunk data (step S101). If it is determined that the data is not list chunk data (step S101: NO), the communication device 10 ends this process. If it is determined that the read data is list chunk data (step S101: YES), the communication device 10 expands the list chunk into the RAM (step S102).

[0053] Next, the communication device 10 acquires the data size of the list chunk expanded into the RAM (step S103).

[0054] Next, the communication device 10 acquires the Type ID and determines whether the Type ID = adtl (step S104). If it is determined that the Type ID is not adtl (step S104), the communication device 10 ends this process. If it is determined that the Type ID = adtl (step S104), the communication device 10 proceeds to step S105 and subsequent steps.

[0055] In steps S105 to S110, the communication device 10 executes a reading process according to the data size of the chunk data. Specifically, within the size of the chunk data, the communication device 10 repeats the following process. The communication device 10 acquires an address (step S106). Next, the communication device 10 advances the address to be read by 4 bytes (step S107). Next, the communication device 10 acquires the peer ID (step S108). Next, the communication device 10 advances the address to be read by 4 bytes (step S109). The communication device 10 repeats the above process until the processing for the data size is completed (step S110). After the processing for the data size is completed, the communication device 10 ends the process.

[0056] Next, with reference to FIG. 9, a process of recording the counterpart ID when recording a received signal received from another communication device will be described. FIG. 9 is a flowchart showing the process of recording the received signal.

[0057] The communication device 10 determines whether there is an instruction to start recording the voice signal included in the received signal (step S111). If it is determined that there is no instruction to start recording the voice signal (step S111: NO), the communication device 10 repeats step S111. If it is determined that there is an instruction to start recording the voice signal (step S111), the communication device 10 proceeds to step S112.

[0058] In step S112, the communication device 10 acquires the ID of the counterpart included in the received signal (step S112).

[0059] Next, the communication device 10 determines whether the ID of the counterpart has changed compared to the previous recording process (step S113). If it is determined that the ID of the counterpart has not changed (step S113: NO), the communication device 10 proceeds to step S116. On the other hand, if it is determined that the ID of the counterpart has changed (step S113: NO), the communication device 10 proceeds to step S114.

[0060] In step S114, the communication device 10 adds the changed ID of the counterpart (step S114).

[0061] Next, when the communication device 10 adds the ID of the counterpart, it adds the recording start address to the ID of the counterpart in the data to be recorded (step S115).

[0062] In step S116, the communication device 10 determines whether there is an instruction to stop recording (step S116). If it is determined that there is no instruction to stop recording (step S116: NO), the communication device 10 returns to step S112. If it is determined that there is an instruction to stop recording (step S116: YES), the communication device 10 ends the process.

[0063] Next, with reference to FIG. 10, the talk-back process during the reproduction of recorded data executed by the communication device 10 will be described. FIG. 10 is a flowchart showing the talk-back process when reproducing the recorded voice.

[0064] First, the communication device 10 determines whether there is an instruction to reproduce the recorded data (step S121). If it is determined that there is no instruction to reproduce the recorded data (step S121: NO), the communication device 10 repeats step S121. If it is determined that there is an instruction to reproduce the recorded data (step S121: YES), the communication device 10 proceeds to step S122.

[0065] In step S122, the communication device 10 acquires the reproduction address related to the reproduced voice signal (step S122). Next, the communication device 10 performs a talk-back display on the display unit 11 (step S123).

[0066] Subsequently, the communication device 10 determines whether the PTT switch has been pressed (step S124). If it is determined that the PTT switch has not been pressed (step S124: NO), the communication device 10 returns to step S122. If it is determined that the PTT switch has been pressed (step S124: YES), the communication device 10 proceeds to step S125.

[0067] In step S125, the communication device 10 temporarily stops the reproduction of the voice (step S125). Further, as a talk-back process, the communication device 10 transmits a signal related to the voice picked up by the microphone 16 of the communication device 10 (step S126).

[0068] Next, the communication device 10 determines whether the pressed PTT switch has been released (step S127). If it is determined that the PTT switch has not been released (step S127: NO), the communication device 10 repeats step S127. If it is determined that the PTT switch has been released (step S127: YES), the communication device 10 ends the transmission of the transmission signal (step S128).

[0069] Next, the communication device 10 resumes the playback of the paused voice (step S129). Subsequently, the communication device 10 determines whether or not the stop of the currently-played voice has been instructed (step S130). If it is determined that the stop of the currently-played voice has not been instructed (step S130: NO), the communication device 10 returns to step S122 and repeats the process. If it is determined that the stop of the currently-played voice has been instructed (step S130: YES), the communication device 10 ends this process.

[0070] As described above, the communication device 10 according to the first embodiment has been described. The communication device 10 according to the first embodiment may receive a signal from another communication device via a repeater as shown in FIG. 3, or may directly receive a signal without passing through a repeater. With the above-described configuration and functions, the communication device 10 can transmit and receive two signals compliant with DMR.

[0071] Also, for example, when the communication device 10 receives a second received signal with a higher priority than the first received signal in the second slot after receiving the first received signal in the first slot, the communication device 10 switches the target of the voice output from the first slot of the first received signal to the second slot of the second received signal. Further, the communication device 10 causes the recording device to start recording at least a signal corresponding to the voice signal among the first received signals. Thereby, the communication device 10 can suppress the user from missing the voice of a relatively low-priority counterpart station.

[0072] Also, when the communication device 10 is not receiving signals in both the first slot and the second slot and is playing back the recorded voice data, when the PTT switch is pressed, the communication device 10 transmits a transmission signal to the counterpart station related to the voice data being played back. Thereby, the communication device 10 can easily resume communication with the counterpart station related to the recorded received signal.

[0073] As described above, according to the present embodiment, it is possible to provide a communication device or the like that suppresses problems due to slot switching.

[0074] <Embodiment 2> Next, Embodiment 2 will be described. The communication device 10 according to Embodiment 2 differs from Embodiment 1 in the processing performed by the control unit 18.

[0075] The control unit 18 according to the present embodiment will be described below. For ease of understanding, the following description takes as an example the case where after receiving the first received signal in the first slot, a second received signal with a higher priority than the first received signal is received in the second slot. In this case, the control unit 18 switches the target of voice output from the first slot of the first received signal to the second slot of the second received signal. Further, the control unit 18 may start recording at least a signal corresponding to the voice signal among the first received signals in the recording device.

[0076] When the reception of the first received signal ends earlier than the reception of the second received signal, the control unit 18 according to the present embodiment sets the preset first period after the reception of the first received signal ends to be able to transmit a transmission signal to the first slot. The end timing of the preset first period may be at least the same as the end of the reception of the second received signal.

[0077] Also, when the reception of the second received signal ends earlier than the reception of the first received signal, the control unit 18 sets the transmission slot to the second slot for the preset second period after the reception of the second received signal ends. The preset second period is the standby time for a normal response.

[0078] Furthermore, when the control unit 18 continues to receive the first received signal after the second period ends, the control unit 18 continues to record the first received signal, and upon the reception of the second received signal ending, starts the voice output of the stored first received signal, that is, the playback of the received voice. Further, for the preset second period after the reception of the first received signal ends, the control unit 18 sets the transmission unit 23 to be able to transmit a transmission signal by the first slot.

[0079] When the control unit 18 continues to receive the first reception signal after the end of the second period, and then after the reception of the first reception signal ends, the period until the end of a preset third period after the voice output of the voice signal in the first slot ends is set as the first slot as the transmission signal. The end timing of the preset third period may be the same as, at the latest, the end of the output of the recorded voice signal, that is, the end of playback. That is, after the first reception signal ends and during voice playback, the control unit 18 uses the first slot as the slot for transmission.

[0080] FIG. 11 is a first diagram for explaining the functions of the communication device according to Embodiment 2. FIG. 11 shows the signal transmission and reception status between terminal A and terminals B and C, and the state of terminal A at this time, from top to bottom along with the flow of time. More specifically, the state of terminal A is shown by rectangles indicating "1" or "2" for the slot to be recorded, the slot for voice output, the slot available for transmission, and the reception slot, from left to right.

[0081] At time T = T11, terminal B starts transmitting a signal in the first slot to terminal A. When terminal A receives the signal from terminal B (the first reception signal), it outputs voice in the first slot and sets the transmission available slot to the first slot. Note that since the communication device 10 performs half-duplex communication, transmission of a signal from terminal A to terminal B becomes possible after the transmission of a signal from terminal B ends.

[0082] Next, at time T12 after time T11, terminal C starts transmitting a signal in the second slot to terminal A. Here, the priority of the signal transmitted from terminal C is set higher than the priority of the signal transmitted from terminal B. When terminal A receives the signal in the second slot (the second reception signal), it reads the priority and switches the settings of the voice output slot and the transmission available slot to the second slot. As a result, the voice output from the speaker switches from the first reception signal to the second reception signal. Also, terminal A starts recording the first reception signal related to the first slot in the recording device.

[0083] Next, at time T13 after time T12, terminal B ends the transmission of the signal to terminal A. Accordingly, terminal A causes the recording device to end the recording of the first received signal. Note that the data from time T12 to time T13 shown in FIG. 11 is referred to as recording data D11.

[0084] Next, in the first period P11 from time T13 to time T15, the transmission-enabled slot is set to the first slot. That is, even if the voice output from the speaker is for the second slot, the communication device 10 according to the present embodiment enables signal transmission to the first slot for a predetermined period immediately after the reception of the first slot ends. In other words, the communication device 10 according to the present embodiment temporarily permits transmission to terminal B even while the voice of the received signal related to terminal C is being output during the first period P11 after the transmission of terminal B ends and before the transmission of terminal C ends. Thereby, the communication device 10 can notify the user of terminal B of the status of terminal A. The status of terminal A is, for example, not having listened to the voice transmitted from terminal B from the middle, or outputting the received signal of terminal C having a higher priority than terminal B. Note that if the communication device 10 continues to receive the second received signal from terminal C after a predetermined period has elapsed, the transmission-enabled slot is returned to the second slot.

[0085] Next, at time T15, terminal C ends the transmission of the signal to terminal A. Accordingly, the voice output ends the setting of the second slot. Also, in the period P12 from time T15 to time T16, the communication device 10 continues to set the transmission-enabled slot to the second slot. That is, this period P12 is immediately after the second received signal transmitted from terminal C stops and is a period set to be capable of responding to terminal C.

[0086] Next, at any time T16 when the period P12 ends, the communication device 10 may play back the recorded data D11 recorded by the recording device. When the playback is started, the communication device 10 sets the transmission destination and the transmission available slot based on the recorded content in the same manner as in the first embodiment. For example, the communication device 10 sets the transmission available slot to the first slot.

[0087] Next, at time T17 after time T16, the playback of the recorded data D11 ends. The communication device 10 may set the transmission available slot to the first slot from time T17 until time T18 when a predetermined period P13 has elapsed. Thereby, the communication device 10 enables a response to the terminal B regarding the voice for which the playback has ended.

[0088] Next, with reference to FIG. 12, the processing of the communication device according to the present embodiment will be further described. FIG. 12 is a first sequence diagram showing the processing executed by the communication device according to the second embodiment. The sequence diagram shown in FIG. 12 corresponds to the operations of the terminals A, B, and C shown in FIG. 11, respectively.

[0089] First, the terminal B starts transmitting a signal to the terminal A (step S211). Next, the terminal A receives the signal transmitted by the terminal B as a first received signal in the first slot, and outputs the voice related to the first received signal from the speaker (step S212).

[0090] Next, the terminal C starts transmitting a signal with relatively high priority to the terminal A (step S213). The terminal A receives the signal transmitted by the terminal C as a second received signal in the second slot (step S214). The communication device 10 compares the priority of the first received signal and the priority of the second received signal (step S215), and switches the voice output from the first received signal to the second received signal. Also, the communication device 10 starts recording the first received signal (step S216). Therefore, the terminal A continues to output the voice of the second received signal, which is the signal transmitted from the terminal C, while continuing to record the first received signal, which is the signal transmitted from the terminal B.

[0091] Next, terminal B finishes transmitting a signal to terminal A (step S217). Accordingly, terminal A finishes recording the first received signal (step S218). At this point, although terminal A continues to output the voice of the second received signal, the user of terminal A can recognize, by means such as display, that the signal (the first received signal) corresponding to the first slot, which is the back slot shown above, has ended.

[0092] Next, in the first period P11 shown in FIG. 11, terminal A is set such that the user of terminal A transmits a signal to terminal B. Specifically, terminal A sets the transmission available slot to the first slot from the end time of the transmission using the first slot by terminal B until the end of the transmission using the second slot by terminal C.

[0093] Terminal A determines whether an operation to respond to terminal B has been performed by an operation of the user of terminal A (step S219). That is, in the first period P11 shown in FIG. 11, terminal A determines whether an operation to transmit a signal to terminal B has been performed by an operation of the user of terminal A. When the user of terminal A responds to terminal B (step S219: YES), terminal A transmits a predetermined message or any voice uttered by the user of terminal A to terminal B (step S220). On the other hand, when the user of terminal A does not respond to terminal B (step S219: NO), terminal A skips step S220. Next, terminal C finishes transmitting a signal to terminal A (step S221). Although the above operations have been described as being executed by human operations, when the conditions for executing the above-described processing are satisfied, a stereotyped message, for example, a message with content such as "Your signal has been interrupted by the reception of a prioritized signal" may be automatically sent.

[0094] As described above, it is possible to suppress the problem that occurs in the information transmission from the user of terminal B due to the slot switching caused by the start of transmission of terminal C.

[0095] Next, the case where the transmission of terminal B shown in FIG. 13 ends first, that is, the case where the first reception signal ends first, will be described. FIG. 13 is a second diagram for explaining the functions of the communication device according to Embodiment 2. FIG. 13 is different from the example of FIG. 11 in that the transmission of terminal B to terminal A ends later than the transmission of terminal C to terminal A.

[0096] At time T = T21, terminal B starts transmitting the signal of the first slot to terminal A. When terminal A receives the first reception signal of terminal B, it outputs the voice of the first slot and sets the transmission available slot to the first slot.

[0097] Next, at time T22 after time T21, terminal C starts transmitting the signal of the second slot to terminal A. Here, as in the case shown in FIG. 11, when terminal A receives the second reception signal of the second slot, it reads the priority and switches the setting of the voice output slot and the transmission available slot to the second slot. As a result, the voice output from the speaker switches from the first reception signal to the second reception signal. Also, terminal A starts recording the first reception signal related to the first slot in the recording device. Note that the data from time T22 to time T25 shown in FIG. 13 is referred to as recording data D21.

[0098] Next, at time T23 after time T22, terminal C ends the transmission of the signal to terminal A. Along with this, terminal A ends the voice output of the signal received in the second slot. Also, in the period P21 from time T23 to time T24, the communication device 10 continues to set the transmission available slot to the second slot. That is, this period P21 is the period immediately after the second reception signal transmitted from terminal C stops and is set to be responsive to terminal C.

[0099] Next, at time T24 when the period P21 ends, terminal A starts playing back the recording data D21 recorded by the recording device. After time T24, if the transmission of terminal B continues, terminal A continues recording to the recording device.

[0100] Next, when the terminal B finishes transmitting a signal to the terminal A at time T25 after time T24, the terminal A causes the recording device to finish recording the first received signal (recording data D21). At this point, the terminal A continues to play back (output audio) the recording data D21, but the user of the terminal A can recognize, by means such as display, that the signal (first received signal) in the first slot has ended due to the stop of recording or the disappearance of the first received signal.

[0101] Next, in the second period P22 shown in FIG. 13, the terminal A is set so that the user of the terminal A can permit signal transmission to the terminal B. Specifically, the terminal A sets the first slot to be transmittable from the end time (time T25) of the transmission using the first slot by the terminal B until the end of the playback of the recording data D21 (time T26). Also, when the transmission by the terminal B ends during the period P21, after the end of the period P21, since the transmission using the first slot by the terminal B has already ended, the terminal A starts playing back the recording data D21 and sets the first slot as a transmittable slot. That is, in the communication device 10 according to the second embodiment, when the playback of the recording data D21 has started and the first received signal has ended in the terminal A, the first slot is set as a transmittable slot.

[0102] Next, at time T26 after time T25, the playback of the recording data D21 ends. The communication device 10 may maintain the setting of the transmittable slot (the setting of the first slot) from time T26 until time T27 when a predetermined third period P22 has elapsed. Thereby, the communication device 10 may enable a response to the terminal B regarding the audio whose playback has ended.

[0103] Next, with reference to FIG. 14, the processing in the situation shown in FIG. 13 will be further described. FIG. 14 is a second sequence diagram showing the processing executed by the communication device according to the second embodiment.

[0104] First, terminal B starts transmitting a signal to terminal A (step S311). Next, terminal A receives the signal transmitted by terminal B as a first received signal in the first slot, and outputs the voice related to the first received signal from the speaker (step S312).

[0105] Next, terminal C starts transmitting a signal with relatively high priority to terminal A (step S313). Terminal A receives the signal transmitted by terminal C as a second received signal in the second slot (step S314). The communication device 10 compares the priority of the first received signal with the priority of the second received signal (step S315), switches the voice output from the first received signal to the second received signal, and starts recording the first received signal (step S316).

[0106] Next, terminal C ends the signal transmission to terminal A (step S317). Accordingly, terminal A determines whether to respond to terminal C (step S318). That is, terminal A determines whether the user of terminal A transmits a signal to terminal C during the period P21 shown in FIG. 13. When it is determined to respond to terminal C (step S318: YES), terminal A transmits a predetermined message or any voice uttered by the user of terminal A to terminal C (step S319). On the other hand, when it is determined not to respond to terminal C (step S318: NO), terminal A skips step S319.

[0107] Next, after the period P21 ends, terminal A starts playing back the recorded first received signal (recording data D21) (step S320).

[0108] Next, while continuing to play back the recorded first received signal, terminal A continues to record the first received signal. Terminal B ends the signal transmission to terminal A (step S321). Accordingly, terminal A ends the recording of the first received signal (step S322). Further, terminal A ends the playback of the first received signal (step S323).

[0109] The terminal A determines whether an operation in response to the terminal B has been performed by the operation of the user of the terminal A (step 324). That is, in the second period P22 shown in FIG. 13, the terminal A determines whether an operation of transmitting a signal to the terminal B has been performed by the operation of the user of the terminal A. When the user of the terminal A responds to the terminal B (step S324: YES), the terminal A transmits a predetermined message or any voice uttered by the user of the terminal A to the terminal B (step S325). On the other hand, when the user of the terminal A does not respond to the terminal B (step S324: NO), the terminal A skips step S325. Although the above operations have been described as being performed by manual operations, when the conditions for executing the above-described processing are satisfied, a stereotyped message, for example, a message with the content "Your signal has been interrupted by the reception of a priority signal", may be automatically sent.

[0110] Note that when responding during the reproduction of the first received signal, the communication device 10 may temporarily stop the reproduction process of the recording data D21 when the PTT switch is pressed, and resume the reproduction after the PTT switch is released.

[0111] As described above, the second embodiment has been described. As described above, when the transmission of the first slot with a relatively low priority ends before the transmission of the second slot with a relatively high priority in the communication device 10 according to the second embodiment, the communication device 10 temporarily enables a response to the terminal B related to the first slot.

[0112] In this case, the communication device 10 cannot transmit the voice uttered to the terminal B while listening to the voice transmitted from the terminal C. Therefore, for example, the communication device 10 may transmit a predetermined text message to the terminal B in such a situation.

[0113] As described above, according to the second embodiment, it is possible to provide a communication device or the like that suppresses problems caused by slot switching.

[0114] <Embodiment 3> Next, Embodiment 3 will be described. The communication device 10 according to Embodiment 3 is different from the above-described embodiments in that it can transmit a predetermined interrupt request signal to the other station that is transmitting a signal to its own station.

[0115] The interrupt request signal according to the present embodiment is a signal transmitted from the communication device receiving a signal to the communication device transmitting a signal at a predetermined timing when "call interruption" is executed in the DMR standard. Call interruption is a technique in which the other station transmitting a signal switches to receiving for a predetermined period (for example, a period of one slot) at a predetermined timing, and when the other station transmitting a signal to its own station switches to receiving as described above, its own station (communication device) transmits an interrupt request signal, and the other station that has received the interrupt request signal interrupts the transmission. The above-described predetermined timing is such that the information is transmitted from the other station to its own station before the predetermined timing is reached. The communication device 10 according to the present embodiment is set to be able to transmit an interrupt request signal to other communication devices, and the other communication devices are set to be able to receive the interrupt request signal.

[0116] When the control unit 18 according to the present embodiment receives a first received signal in a first slot and then receives a second received signal having a higher priority than the first received signal in a second slot, it switches the target of voice output from the first slot of the first received signal to the second slot of the second received signal, and transmits an interrupt request signal as a transmission signal to the transmission source of the first received signal.

[0117] FIG. 15 is a first sequence diagram showing the processing executed by the communication device according to Embodiment 3. The sequence diagram shown in FIG. 15 is different from the sequence diagram shown in FIG. 12 in the processing between step S215 and step S219. Further, the sequence diagram shown in FIG. 15 is the same as the sequence diagram shown in FIG. 12 except for the above-described differences.

[0118] The terminal A according to this embodiment, the communication device 10 compares the priority of the first received signal and the priority of the second received signal (step S215), and switches the voice output from the first slot of the first received signal to the second slot of the second received signal (step S410). Here, the terminal A starts outputting the voice signal related to the second received signal, and continues to detect the first received signal. Also, the terminal A operates notification means indicating that the first received signal is being continuously received. That is, for example, the terminal A lights a display meaning the above-mentioned "Back Slot Busy" or an LED indicating that the first received signal is being received. Note that the terminal A may start recording the first signal as in Embodiment 1 and Embodiment 2.

[0119] Next, the terminal A transmits an interrupt request signal to the terminal B (step S411). Note that the terminal A may be set to automatically transmit this interrupt request signal. Also, the terminal A may be set to transmit this interrupt request signal by a user operation.

[0120] While transmitting a transmission signal to the terminal A, the terminal B receives an interrupt request signal in parallel. By recognizing the interrupt request signal transmitted from the terminal A, the terminal B ends the transmission of the transmission signal to the terminal A (step S412). In this case, for example, the terminal B may display a message indicating that the interrupt request signal has been received on the display unit of the terminal B. By visually recognizing the message displayed on the display unit of the terminal B, the user of the terminal B can recognize that the transmission to the terminal A has stopped, that is, the transmission has been stopped due to a call interruption. The user of the terminal B aborts the transmission operation since a call interruption has been received.

[0121] On the one hand, terminal A receives the transmission signal from terminal C, that is, the second received signal, and while outputting the voice, waits for the end of the transmission from terminal B, that is, the first received signal. Since the detection of the first received signal continues at terminal A, it can be recognized that terminal B has stopped transmitting due to the interruption of the detection of the first received signal. For example, terminal A may stop the display of "Back Slot Busy" or the notification by notification means such as an LED described above, or may notify that terminal B has stopped transmitting by a display such as "Back Slot Open" indicating that the back slot is empty or an LED of a different color.

[0122] Next, terminal A determines whether to respond to terminal B (step S219). That is, similar to Embodiment 2, in the first period P11 shown in FIG. 11, terminal A determines whether the user of terminal A transmits a signal to terminal B. When it is determined to respond to terminal B (step S219: YES), terminal A transmits a predetermined message or any voice uttered by the user of terminal A to terminal B (step S220). On the other hand, when it is determined not to respond to terminal B (step S219: NO), terminal A skips step S220. Embodiment 3 is different from Embodiment 2 in that terminal A performs call interruption to stop the transmission of terminal B. In Embodiment 2, the processing differs depending on which of the first received signal and the second received signal ends first, but in Embodiment 3, the first received signal can be ended first by call interruption immediately after the start of reception of the second received signal.

[0123] In Embodiment 3, the terminal A can stop the transmission of the terminal B. Therefore, thereafter, the terminal A may start transmitting to the terminal B regardless of the judgment of the user of the terminal A. However, depending on the content of the second received signal, there may be cases where the content must be listened to. Therefore, the terminal A may leave it to the judgment of the user of the terminal A whether or not the terminal A performs transmission. In any case, the slot set for transmission during the period of receiving the second received signal is set not to the slot of the second received signal currently being received and outputting voice, but to the slot of the first received signal, that is, the slot used for communication with the terminal B.

[0124] The above is the description of Embodiment 3. Note that Embodiment 3 may not have the recording device 14. However, the terminal A, which is the communication device 10 according to the present embodiment, may be provided with the recording device 14 when leaving the transmission of the interrupt request signal to the user operation of the terminal A, and may be configured to record the first received signal in the recording device 14. That is, the user of the terminal A can select whether to issue an interrupt request to forcibly stop the transmission of the terminal B or to wait until the transmission ends while recording the transmission of the terminal B.

[0125] As described above, according to Embodiment 3, it is possible to provide a communication device or the like that suppresses problems due to slot switching.

[0126] <Embodiment 4> Next, Embodiment 4 will be described. Embodiment 4 includes a recording device 14, determines the degree of priority of the second received signal, and decides whether to issue an interrupt request or perform recording. That is, Embodiment 4 is different from Embodiment 3 in which the transmission of the interrupt request signal is left to the user's operation in the above point.

[0127] Throughout this disclosure, it has been consistently described that when the priority of the second received signal is higher than that of the first received signal, the communication device 10 switches the signal for outputting voice to the second received signal. In the case of Embodiment 2, the content transmitted by the first received signal may be recorded, and it is possible for the user of terminal A to be fully aware of all the content from terminal B. However, in the case of Embodiment 3, terminal A stops the first received signal halfway. Therefore, not all of the content that terminal B intended to transmit will reach the user of terminal A. Also, regarding whether to record the first received signal or not, in Embodiment 3, it was stated that it may be determined based on whether the user of terminal A performs an interrupt request operation or not. In the present embodiment, it is characterized in that whether to record the first received signal or not is determined by the difference in priority between the first received signal and the second received signal or the absolute priority for either processing.

[0128] In Embodiment 4, the control unit 18 determines and controls whether to record the first received signal or transmit an interrupt request signal (call interruption) to the transmission source of the first received signal based on the relationship between the priorities of the first received signal and the second received signal. Specifically, the control unit 18 determines and controls whether to record the first received signal or transmit an interrupt request signal (call interruption) to the transmission source of the first received signal based on the difference in priority or the absolute priority between the first received signal and the second received signal. The control unit 18 may quantify the priority based on the information regarding the priority output from the baseband signal processing unit 19. Regarding the quantification of the priority, for example, an emergency call is set to 3, group communication is set to 3, and individual communication is set to 1. Regarding the determination criterion, when the difference is 1, recording is performed, and when the difference is 2, call interruption is performed. Also, a determination such as performing call interruption when the second received signal is an emergency call and recording in other cases may be made.

[0129] FIG. 16 is a sequence diagram showing the processing executed by the communication device according to Embodiment 4. The sequence diagram shown in FIG. 16 shows an example where the priority included in the first received signal is lower than the priority included in the second received signal, in other words, where the priority included in the second received signal is higher than the priority included in the first received signal. Of course, when the priority included in the first received signal is higher than the priority included in the second received signal, terminal A continues the voice output related to the first received signal received from terminal B.

[0130] Terminal A according to the present embodiment compares the priority included in the first received signal received from terminal B with the priority included in the second received signal received from terminal C (step S215).

[0131] As described above, when the priority included in the second received signal is lower than the priority included in the first received signal, terminal A continues to receive the first received signal. When the priority included in the second received signal is higher than the priority included in the first received signal, terminal A switches to the voice output of the second received signal (step S510).

[0132] Next, when the priority included in the second received signal is higher than the priority included in the first received signal, terminal A further determines whether the priority of the first received signal and the priority of the second received signal satisfy a predetermined relationship. More specifically, terminal A determines whether terminal B is the target of an interrupt request based on the relationship between the priority of the first received signal and the priority of the second received signal (step S511). When it is determined that terminal B is the target of the interrupt request (step S511: YES), terminal A transmits an interrupt request signal to terminal B (step S512). Also in this case, terminal A skips step S513 described later.

[0133] On the other hand, when it is determined that terminal B is not the target of the interrupt request (step S511: NO), terminal A starts recording the first received signal (step S513).

[0134] If the answer is YES in step S511, as the subsequent processing shown in FIG. 16, terminal A executes the same processing as the subsequent processing shown in step S411 in Embodiment 3. That is, terminal A stops the transmission of terminal B by an interrupt request signal, and switches the transmission slot to the slot that was used for communication with terminal B until the transmission of terminal C stops.

[0135] On the other hand, if the answer is NO in step S511, as the subsequent processing shown in FIG. 16, terminal A executes the same processing as the subsequent processing shown in step S216 or step S316 in Embodiment 2. That is, terminal A continuously records the first received signal from terminal B and outputs the voice of the second received signal. The processing differs depending on whether the transmission of terminal B or terminal C ends first, which is the same as in Embodiment 2.

[0136] The above is the description of Embodiment 4. Note that the priority setting according to this embodiment may be set according to the numerical value of the priority, or for example, the relative correspondence between the priority of the signal related to the first slot and the priority of the signal related to the second slot may be set individually. As described above, when the priority of the second received signal (the signal in the second slot) is lower than the priority of the first received signal (the signal in the first slot), the voice output continues to output the voice of the first received signal and does not switch to the second received signal.

[0137] That is, for example, if the priority included in the first received signal is "2" and the priority included in the second received signal is "3" which is higher than 2, it is assumed that an interrupt request signal is set to be transmitted to the first slot. In this case, when the priority included in the first received signal is "1" and the priority included in the second received signal is "3", it may be set that no interrupt request signal is transmitted to the first slot.

[0138] By individually setting the response according to the priority in this way, the communication device 10 according to the present embodiment can flexibly set the response by slot switching. As described above, according to the fourth embodiment, it is possible to provide a communication device or the like that suppresses problems caused by slot switching.

[0139] When the above program is loaded into a computer, it includes a group of instructions (or software code) for causing the computer to perform one or more functions described in the embodiment. The program may be stored in a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, a computer-readable medium or a tangible storage medium includes random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD), or other memory technologies, CD-ROM, digital versatile disc (DVD), Blu-ray (registered trademark) disc, or other optical disc storage, magnetic cassette, magnetic tape, magnetic disk storage, or other magnetic storage devices. The program may be transmitted on a transient computer-readable medium or a communication medium. By way of example and not limitation, a transient computer-readable medium or a communication medium includes electrical, optical, acoustic, or other forms of propagated signals.

[0140] Note that the present invention is not limited to the above embodiment, and can be appropriately changed without departing from the spirit.

Explanation of Reference Numerals

[0141] 10 Communication device 11 Display unit 12 Operation unit 13 Peripheral unit 14 Recording device 15 Speaker 16 Microphone 17 Antenna 18 Control unit 19 Baseband signal processing unit 20 Audio signal decoding unit 21 Audio signal processing unit 22 Transceiver unit 23 Transmitter unit 24 Receiver unit 25 RF switch unit 26 PTT switch 27 Non-volatile memory 100 Signal processing block 101 Digital signal detection unit 102 Chapter generation unit 104 Received audio conversion unit 105 Record data generation unit 106 Recorded audio control unit 107 Audio signal extraction unit 108 Associated information extraction unit 109 PTT operation detection unit 110 Audio output control unit 111 Display control unit

Claims

1. A receiving circuit that receives in a first slot or a second slot by a time-division multiple access method, An audio signal decoding circuit that decodes an audio signal with either the first received signal received in the first slot or the second received signal received in the second slot as the target of audio output, A recording device that is set to be able to record at least an audio signal of at least one of the first received signal and the second received signal, A baseband signal processing circuit that determines the priority of the target of audio output from the information included in the first received signal and the second received signal and outputs information regarding the priority, When the second received signal with a higher priority than the first received signal is received in the second slot after the first received signal is received in the first slot, the slot that is the target of audio output is switched from the first slot of the first received signal to the second slot of the second received signal based on the information regarding the priority, and a control circuit that causes the recording device to start recording at least a signal corresponding to the audio signal among the first received signals, A transmission circuit that transmits a transmission signal corresponding to the first slot or the second slot, and is provided with, When the reception of the first received signal ends earlier than the reception of the second received signal, the control circuit sets the transmission circuit to be able to transmit a transmission signal by the first slot during a preset first period after the reception of the first received signal ends, A communication device.

2. The communication device according to claim 1, wherein the timing of the end of the first period is at least the same as the end of the reception of the second received signal.

3. A receiving circuit that receives in a first slot or a second slot by a time-division multiple access method, An audio signal decoding circuit that decodes an audio signal with either the first received signal received in the first slot or the second received signal received in the second slot as the target of audio output, A recording device that is set to be able to record at least an audio signal of at least one of the first received signal and the second received signal, A baseband signal processing circuit that determines the priority of the target of audio output from the information included in the first received signal and the second received signal and outputs information regarding the priority, After receiving the first received signal in the first slot, when the second received signal with a higher priority than the first received signal is received in the second slot, a control circuit switches a slot to be an object of voice output from the first slot of the first received signal to the second slot of the second received signal based on information regarding the priority, and causes the recording device to start recording at least a signal corresponding to a voice signal among the first received signals; a transmission circuit that transmits a transmission signal corresponding to the first slot or the second slot; When the control circuit continues to receive the first received signal after the reception of the second received signal has ended, the control circuit continues to record the first received signal, and upon the reception of the second received signal ending, starts voice output of the stored first received signal; Furthermore, the control circuit sets the transmission circuit to be able to transmit a transmission signal by the first slot during a preset second period after the reception of the first received signal has ended; The start timing of the second period is after the start of voice output of the stored first received signal and after the reception of the first received signal has ended; The end timing of the second period is at the same timing as at least the end of voice output of the stored first received signal at the latest. A communication device. According to claim 4, a step of receiving in a first slot or a second slot by a time-division multiple access method; a step of decoding a voice signal with either the first received signal received in the first slot or the second received signal received in the second slot as an object of voice output; a step of setting at least one of the first received signal and the second received signal to be able to record at least a voice signal; a step of determining a priority of an object of voice output from information included in the first received signal and the second received signal, and outputting information regarding the priority; After receiving the first received signal in the first slot, when the second received signal with a higher priority than the first received signal is received in the second slot, a step of switching a slot to be an object of voice output from the first slot of the first received signal to the second slot of the second received signal based on information regarding the priority, and starting recording of at least a signal corresponding to a voice signal among the first received signals; A step of transmitting a transmission signal corresponding to the first slot or the second slot. When the reception of the first reception signal ends before the reception of the second reception signal, the control circuit sets the transmission circuit to be able to transmit a transmission signal by the first slot during a preset first period after the reception of the first reception signal ends. Communication method. **Claim 5**: A step of receiving in a first slot or a second slot by a time-division multiple access method; A step of decoding an audio signal with either the first reception signal received in the first slot or the second reception signal received in the second slot as an object of audio output; A step of setting at least one of the first reception signal and the second reception signal to be recordable at least for an audio signal; A step of determining a priority for an object of audio output from information included in the first reception signal and the second reception signal, and outputting information regarding the priority; When the second reception signal having a higher priority than the first reception signal is received in the second slot after the first reception signal is received in the first slot, switching the slot that is the object of audio output from the first slot of the first reception signal to the second slot of the second reception signal based on the information regarding the priority, and starting to record a signal corresponding to at least the audio signal among the first reception signals; A step of transmitting a transmission signal corresponding to the first slot or the second slot. When the control circuit continues to receive the first reception signal after the reception of the second reception signal ends, the control circuit continues to record the first reception signal, and upon the reception of the second reception signal ending, starts audio output of the stored first reception signal. Furthermore, during a preset second period after the reception of the first reception signal ends, the control circuit sets the transmission circuit to be able to transmit a transmission signal by the first slot. The start timing of the second period is after the start of audio output of the stored first reception signal and after the reception of the first reception signal ends. The end timing of the second period is at the same timing as the end of audio output of the stored first reception signal at the latest. Communication method.

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