JP4377876B2 - Radio receiver and reception control method - Google Patents

Description

  The present invention relates to a radio receiver and a reception control method for a digital disaster prevention radio system.

  In the digital broadcast disaster prevention radio system, two modes are prepared for the transmission state of the master station according to the ARIB STD-T86 standard. That is, there are two first modes, an intermittent transmission mode in which transmission of one slot for control is always performed and a transmission mode in communication in which transmission is not performed when waiting in the second mode. Set the mode to receive.

  In the transmission mode during a call, it is usually in a standby state in which the operation of some circuits is suspended, and when a radio wave arrives from the master station to its own station, the operation of the suspension circuit is restored and normal reception operation is started. Power operation. However, which transmission mode is used is determined by local governments such as municipalities that operate the broadcast disaster prevention radio system, and therefore the transmission mode used for each local government varies.

  In the conventional broadcast disaster prevention radio system, it is necessary to set the radio receiver standby mode for each local government system, and the intermittent transmission mode always performs reception operation, which increases power consumption during standby. There is a problem.

Even in the transmission mode during a call for the purpose of saving power, after receiving radio waves from the master station, receive in a short time during the downtime in order to shorten the rise time until the internal synchronization processing etc. is completed and voice output is possible There is also a method. However, if the transmission from the master station does not match the timing at which the slave station can receive, a reception error will occur, or the transmission (master station) will make the press talk time longer than a certain value. Has to be added (for example, Patent Document 1).
JP 2003-87180 A (Page 8, FIG. 1)

  In the wireless receiver of the conventional digital disaster prevention radio system, it is necessary to set standby reception processing (mode) for each local government, and even when there is no call addressed to the slave station, the control signal of the intermittent slot is periodically sent from the master station. In the intermittent transmission mode in which the receiver is transmitted, there is a problem in that the power consumption increases because the receiver is always in a state where the circuit is operating.

  It is an object of the present invention to provide a radio receiver and a reception control method for a digital broadcast disaster prevention radio system that does not require setting of a reception mode and can suppress power consumption during standby.

  In order to achieve the above object, the wireless receiver of the present invention transmits a radio wave of a packet signal from a master station to a wireless receiver as a plurality of slave stations in either a call transmission mode or an intermittent transmission mode. In the radio receiver of the digital disaster prevention radio system for transmitting information by counting the time that the received radio wave carrier exceeds a predetermined level, the counted time is continued for one slot of the packet signal. An incoming call detection unit that outputs incoming information when the time is exceeded, and is controlled to be in either a dormant state or an operating state by an input control signal, and the radio wave of the received packet signal is changed to a required form of the information. And a signal processing circuit that outputs the signal processing circuit, and the control signal that is connected to the incoming call detection unit and puts the signal processing circuit into an operating state when the incoming call information is input. Characterized in that it comprises a control unit which performs control to output to the signal processing circuit.

  The reception control method of the wireless receiver of the present invention includes a signal processing circuit, an incoming detection unit, and a control unit. In the reception control method of the wireless receiver of the digital disaster prevention wireless system for transmitting information by transmitting in any of the intermittent transmission modes, the wireless receiver, the incoming detection unit, the radio wave of the packet signal Receiving and counting the time when the radio wave carrier exceeds a predetermined level, and when the counted time exceeds the duration of one slot of the packet signal, output incoming information to the control unit, The control unit connected to the incoming call detection unit and receiving the incoming call information outputs the control signal for operating the signal processing circuit to the signal processing circuit, and outputs the control signal. There the signal processing circuit that is input consists dormant operating state, characterized by a packet signal of the radio wave to output to the information on the required form to receive.

  According to the present invention, it is possible to provide a radio receiver and a reception control method for a digital broadcast disaster prevention radio system that has a short reception synchronization pull-in time and suppresses power consumption during standby.

  Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a functional configuration of a radio receiver of a disaster prevention radio system according to an embodiment of the present invention.
In FIG. 1, the disaster prevention radio system includes a master station Ma and a plurality of slave stations that receive radio waves transmitted from the master station Ma, in other words, a plurality of radio receivers Sr.

  The radio receiver Sr is connected to an antenna 1 through an internal bus or the like, and includes a front end unit 2 that amplifies a received signal, a detection processing unit 3 that detects and demodulates a digital signal of the received signal, and amplifies the demodulated signal as an audio signal. The voice processing unit 4 monitors the received signal from the antenna 1 and outputs an incoming flag when the carrier is continuously received for a predetermined time or longer. The incoming detection unit 5 monitors the incoming flag and operates the wireless receiver. A control unit 6 for controlling to a standby (pause) state or an operation (active) state, a speaker 7 for outputting sound, an input unit such as a switch and a dial, and a display unit such as a lamp, and an operation of the radio receiver Sr And an operation unit 8 for inputting and setting a mode.

  In FIG. 1, the radio wave received by the antenna 1 of the radio receiver Sr is amplified by the front end unit 2, and the amplified carrier signal is output to the detection processing unit 3 and also to the incoming call detection unit 5. The The front end unit 2 and the incoming call detection unit 5 always operate regardless of the mode setting, but the circuit scale is small, so that the current consumption is small.

  The detection processing unit 3, the audio processing unit 4, and the control unit 6 are always in an operating state when the apparatus is set to the intermittent transmission mode by a switch (not shown) of the operation unit 8, for example. Further, when the transmission mode during a call is set, the time during which no notification of reception of radio waves is not received from the incoming call detection unit 5 is in a pause (standby) state.

  In the radio receiver Sr according to the embodiment of the present invention, a setting position of the automatic mode that does not change the receiving operation by the mode setting is further added to the switch of the operation unit 8, or a receiving operation switching function by the mode setting is provided. It has been deleted.

FIG. 2 is a diagram for explaining a frame configuration of a radio packet transmitted from the master station Ma to the slave station Sr in the disaster prevention radio system defined by ARIB STD-T86, and FIG. 3 is a control slot for the radio packet, FIG. FIG. 4 is a diagram showing the contents of a communication message slot (hereinafter abbreviated as a communication slot).
Next, the operation | movement outline | summary of a disaster prevention radio | wireless system is demonstrated using FIGS. 1-3.

  In FIG. 2A, at the time of message transmission, control slot s0 from the top, communication slots s1 and s2 into which messages such as data are written, slot s3 to handle the second control signal, and slots s4 and s5 into which messages are written again. Packets in superframe units, each of which is a collection of a plurality of frames each consisting of a total of 6 slots, are transmitted repeatedly.

  In FIG. 3, the control slot s0 includes a ramp time R, a preamble AP, a synchronization word SW, a channel type C, a control signal CAC, a guard time G, and a pilot symbol P. In FIG. 4, the communication slot includes a ramp time R, a traffic channel TCH, a high-speed control channel FACCH :, a synchronization word SW, a channel type C, a guard time G, and a pilot symbol P.

  First, the operation process of the radio receiver Sr in the call transmission mode will be described.

  When the switch of the operation unit 8 is set to the call transmission mode, the setting information of the switch is input to the incoming call detection unit 5 via the internal bus. Here, the operation of the radio receiver Sr is the same as that of the conventional radio receiver, that is, the detection processing unit 3 and the audio processing unit 4 are in a dormant state. The control unit 6 may operate constantly, or may be activated from a sleep state when an incoming notification or an incoming flag is input as described later.

  In the call transmission mode, as shown in FIG. 2B, the master station Ma does not transmit the carrier Cr over the entire time corresponding to the slots s0 to s5 in which no message is transmitted. When a message is transmitted, a continuous carrier is always transmitted over all slots s0 to s1 in the packet corresponding to FIG.

  In the radio receiver Sr, since the detection processing unit 3 and the voice processing unit 4 operate only during the time when the carrier Cr is received by the reception notification from the incoming call detection unit 5, the power consumption is reduced in the standby state.

  Prior to transmission of a message for a call, at the start of transmission from the master station, for example, synchronous burst transmission in which several tens of frames in which the control slot is inserted in each of the slots is performed is transmitted. The incoming call detection unit 5 determines the level of the carrier received via the antenna 1 and the front end unit 2, and outputs an incoming call notification to the control unit 6 via the internal bus when a predetermined level is exceeded.

  The control unit 6 that has received the incoming call notification outputs a control signal for activating the detection processing unit 3 and the voice processing unit 4 via an internal bus or the like, and those that have received the control signal change from a sleep state to an operation state.

  And the detection process part 3 receives the carrier signal output from the front end part 2, and starts a detection decoding process. On this occasion. In order for the detection processing unit 3 to perform the decoding process, encoding synchronization or the like is necessary, but the synchronization process requiring these times is established during the reception of the synchronous burst. Then, the detection processing unit 3 detects and decodes the message transmitted subsequent to the synchronous burst, and then the audio processing unit 4 restores the audio to the audio and the audio broadcasting is performed from the speaker 7.

  On the other hand, similarly, in the intermittent transmission mode, when the switch of the operation unit 8 is set to the transmission mode during a call, the setting information of the switch is input to the incoming call detection unit 5 via the internal bus, and the radio receiver Sr All internal configurations are in operation.

  In the intermittent transmission mode, the master station Ma always transmits the control slot to the slot s0 toward the radio receiver Sr even when message transmission such as guidance broadcasting is not performed. As shown in FIG. 2D, the radio wave transmitted from the master station Ma outputs the carrier Cr when it is in the control slot (slot s0), and the carrier Cr is output during the time corresponding to the remaining slots s1 to s5. Not.

  As described above, not only the incoming call detection unit 5 but also all the components of the radio receiver Sr continue to operate without interruption. For example, when receiving a message, the control unit 6 of the radio receiver Sr that is a slave station reads channel information of the control slot that has been detected and decoded, and reproduces voice only in the case of a packet addressed to the local station, 7 is output.

  Therefore, the radio receiver Sr is always set in a reception state in which the activation state is maintained, and power is always consumed even though most of the time is not output. Even in this intermittent transmission mode, the master station Ma transmits a synchronization burst similar to that in the on-call transmission mode before transmitting a message.

FIG. 5 is a diagram illustrating power consumption in the standby (pause) state and the operating state of the wireless receiver Sr.
FIG. 5A shows the power consumption in the conventional transmission mode during a call. The lowest power P1 is consumed in the standby (pause) state, and the rated power P3 is consumed when receiving the synchronous burst and the message.

  FIG. 5B shows the power consumption in the conventional intermittent transmission mode. The power P2 is consumed in the standby (pause) state, and the rated power P3 is consumed when receiving the synchronous burst and the message. In the intermittent reception mode, the receiver Sr does not output sound during standby even if the power of P3 is not always consumed, but consumes power because it performs control slot reception processing.

  In the call reception mode, the incoming call detection unit 5 monitors the level of the received carrier output from the front end unit 2 and outputs an incoming call notification when the level is above a certain level. In order to avoid the influence of noise, the device Sr uses only the reception level information to the extent that smoothing by a low-pass filter or the like is added.

  Therefore, when the radio receiver Sr set in the transmission mode during a call is used in an area where the master station Ma transmits in the intermittent mode, an incoming call notification is output when the control slot is received and the carrier Cr is interrupted. Immediately after entering the sleep state, not only the state of repeated operation and pause becomes unstable, but also power is consumed when receiving the control slot, and the power saving effect is reduced.

  In the radio receiver Sr of the present invention, in the intermittent transmission mode, an automatic reception mode in which no reception operation is performed is provided, and the time during which only the control slot is transmitted conforms to the transmission mode during a call by pausing the voice processing unit 4 and the like. Has achieved a power saving effect. Moreover, the effect which does not need the setting which switches two reception modes is acquired.

  When the switch of the operation unit 8 is set to the automatic reception mode, the setting information of the switch is input to the incoming call detection unit 5 via the internal bus. The wireless receiver Sr is in the same state as the call transmission mode, that is, the detection processing unit 3 and the voice processing unit 4 are in a dormant state.

FIG. 6 is a block diagram showing a functional configuration of the incoming call detection unit according to the embodiment of the wireless receiver of the present invention.
In FIG. 6, the incoming call detection unit 5 includes a level determination unit 51 similar to the conventional incoming call detection unit 5, a newly provided timer 52, and an incoming call determination unit 53. The level determination unit 51 monitors the level of the carrier input from the front end unit 2 and outputs an incoming call notification to the timer 52 and the incoming call determination unit 53 when a predetermined level is exceeded.

  The timer 52 measures the time during which the incoming call notification continues, and outputs that the incoming call is being received to the incoming call determination unit 53 when it continues beyond the length of one slot (for example, 80/6 + α = 15 (msec)). The incoming call determination unit 53 outputs the incoming call flag f to the control unit 6 only when the incoming call notification is continuously received for the predetermined time or longer.

  The control unit 6 operates (active) only when the incoming flag f is present, and outputs a control signal that activates the detection processing unit 3 and the voice processing unit 4. Therefore, the detection processing unit 3 and the sound processing unit 4 are also in a pause state.

FIG. 7 is a timing chart for explaining the operation of the incoming call detection unit 5.
The radio receiver Sr set to the automatic reception mode operates in the same manner as the operation in the conventional transmission mode during a call while the control unit 6 receives the incoming flag f. However, the time length of 13.3 msec (see FIG. 7A) of the control slot in the intermittent mode is insufficient for 15 msec of the incoming flag f output condition, so no reception processing is performed (see FIG. 7B). . When a synchronous burst transmitted before the message is transmitted (see FIG. 7 (c)), a continuous carrier of 15 msec or longer is received, so an incoming flag is output (FIG. 7 (d)). (Ref.) The reception process is started and the audio signal is broadcast.

  Note that the incoming call detection unit 5 may have a single timer 52 and incoming call determination unit. Further, the control unit 6 may also execute the function of the incoming call detection unit 5 to control the detection processing unit 3 and the voice processing unit 4.

  As described above, the wireless receiver (slave station) according to the present invention is configured such that the configuration that has been in the continuous operation state in the intermittent transmission mode is paused in the standby state, and is activated when the continuous carrier starting from the synchronous burst is received. Power-saving operation that operates only when audio playback is required is possible.

  In the above description, the configuration (circuit) that pauses in the intermittent transmission mode and the transmission mode during a call is described with the detection processing unit 3 and the voice processing unit 4 or the control unit 6 added. For example, only the voice processing unit 4 may be paused, or a part of the configuration or a part where the configurations are appropriately combined may be paused.

  In the above description, audio broadcasting is described as an example, but information output in the form of characters, documents, videos, and the like may be transmitted to the information terminal instead of the audio message. In that case, the sound processing unit may be read as an information processing unit, a video processing unit, or the like according to the form of information.

  The wireless receiver to which the present invention is applied may be provided with only an “automatic mode” in which mode setting of the operation unit is omitted and the modes are not distinguished.

The block diagram which shows the function structure of the radio | wireless receiver of the disaster prevention radio | wireless system which concerns on the Example of this invention. − The figure explaining the frame structure of the radio | wireless packet which a parent station transmits with a disaster prevention radio | wireless system. The figure which shows the structure of the control slot of a wireless packet. The figure which shows the structure of the slot of the message for communication. Explanatory drawing of the power consumption of a radio receiver. The block diagram which shows the function structure of the incoming call detection part which concerns on the Example of the wireless receiver of this invention. The operation | movement timing diagram of an incoming call detection part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antenna 2 Front end part 3 Detection processing part 4 Voice processing part 5 Incoming call detection part 51 Timer 6 Control part 7 Speaker 8 Operation part

Claims (4)

In a radio receiver of a digital disaster prevention radio system that transmits information by transmitting a packet signal radio wave from a master station to a radio receiver that is a plurality of slave stations in either a call transmission mode or an intermittent transmission mode ,
An incoming detection unit that counts a time when the received radio wave carrier exceeds a predetermined level and outputs the incoming information when the counted time exceeds the duration of one slot of the packet signal;
A signal processing circuit that is controlled by an input control signal to be in either a dormant state or an operating state, and outputs a radio wave of the received packet signal in a required form of the information;
And a control unit that is connected to the incoming call detection unit and that controls the signal processing circuit to output the control signal to the signal processing circuit when the incoming call information is input. Wireless receiver. In a radio receiver of a digital disaster prevention radio system that performs audio broadcasting by transmitting a radio wave of a packet signal from a master station to a radio receiver that is a plurality of slave stations in either a call transmission mode or an intermittent transmission mode ,
An incoming detection unit that counts a time when the received radio wave carrier exceeds a predetermined level and outputs the incoming information when the counted time exceeds the duration of one slot of the packet signal;
A signal processing circuit that is controlled by an input control signal to be in a pause state or an operating state, and outputs the radio wave of the received packet signal as audio of the audio broadcast;
A control unit that is connected to the incoming call detection unit and that controls the signal processing circuit to output the control signal to the signal processing circuit when the incoming call information is input. Wireless receiver. It is equipped with a signal processing circuit, an incoming call detection unit, and a control unit, and transmits radio waves of packet signals from a master station to a wireless receiver, which is a plurality of slave stations, in either a call transmission mode or an intermittent transmission mode. In the reception control method of the wireless receiver of the digital disaster prevention wireless system that transmits information by:
The wireless receiver is
The incoming detection unit receives a radio wave of the packet signal, counts a time when the carrier of the radio wave exceeds a predetermined level, and the counted time exceeds a duration of one slot of the packet signal The incoming call information to the control unit,
The control unit connected to the incoming call detection unit and receiving the incoming call information,
Outputting the control signal to put the signal processing circuit into an operating state to the signal processing circuit;
The signal processing circuit to which the control signal is input is
A radio receiver reception control method, wherein the radio wave packet signal to be received is changed from a dormant state to an operating state and the information is output in a required form. It is equipped with a signal processing circuit, an incoming call detection unit, and a control unit, and transmits radio waves of packet signals from a master station to a wireless receiver, which is a plurality of slave stations, in either a call transmission mode or an intermittent transmission mode. In the reception control method of the radio receiver of the digital disaster prevention radio system that performs audio broadcasting by
The wireless receiver is
The incoming detection unit receives a radio wave of the packet signal, counts a time when the carrier of the radio wave exceeds a predetermined level, and the counted time exceeds a duration of one slot of the packet signal The incoming call information to the control unit,
The control unit connected to the incoming call detection unit and receiving the incoming call information,
Outputting the control signal to put the signal processing circuit into an operating state to the signal processing circuit;
The signal processing circuit to which the control signal is input is
A radio receiver reception control method, wherein the radio wave packet signal is changed from a dormant state to an operating state, and the received radio wave packet signal is output as audio of the audio broadcast.

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