JP2017092723A - Broadcast communication system, broadcast communication equipment and broadcast communication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a broadcast communication system, broadcast communication equipment and broadcast communication method, capable of emitting a broadcast wave at the same timing using the same frequency from a plurality of relay stations by accommodating fluctuations in a propagation path delay due to fading or the like, if any.SOLUTION: The broadcast communication system, broadcast communication equipment and broadcast communication method is configured so that a transmitter transmits multiplexed time information synchronous with a transmission side 1 PPS signal created by the transmitter to a user bit area of broadcast communication data and so that a receiver extracts the time information from the broadcast communication data, creates a reception 1 PPS signal synchronous with the time information, determines a transmission delay time on the basis of a difference between a reference 1 PPS signal created on the basis of GPS signal and the reception 1 PPS signal, subtracts the transmission delay time from a predetermined reference delay time to calculate a timing adjustment time and delays an audio signal by the timing adjustment time to be output to an FM transmitter.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a broadcast communication system that broadcasts at a single frequency, and in particular, even if the propagation path delay fluctuates due to fading or the like, a plurality of relay stations use the same frequency and broadcast waves at the same timing correspondingly. TECHNICAL FIELD The present invention relates to a broadcast communication system, a broadcast communication apparatus, and a broadcast communication method that can emit (output) a message.

[Description of Prior Art]
An audio digital STL (Studio to Transmitter Link) / TTL (Transmitter to Transmitter Link) device used for FM radio broadcasting performs digital modulation / demodulation and transmission / reception of audio signals. The modulated audio signal is received and demodulated, modulated into an FM broadcast wave, and output to a broadcaster that outputs the broadcast wave.
In addition, when operating as a relay broadcast station, in addition to the above-described operation, it also operates as a relay station that digitally modulates the decoded audio signal again and transmits it to another broadcast station.

  By the way, a single frequency network (SFN) used in FM radio broadcasting has a merit that the broadcast frequency can be effectively used because the broadcast service area is configured with a single frequency.

  However, in order to realize this FM synchronous broadcast, it is necessary to synchronize the output timing of the broadcast wave at the main broadcasting station that outputs the FM broadcast wave or at a plurality of relay stations that output the FM broadcast wave at the same frequency.

When a digital modulation method is used, such as an OFDM (Orthogonal Frequency Division Multiplexing) method used in digital television broadcasting, interference of adjacent symbols due to multipath interference can be absorbed by a guard interval. In the case of the analog modulation method used in the above, the influence of interference due to the timing shift (delay difference) of each broadcast wave output becomes large.
Therefore, in the conventional FM synchronous broadcasting, the delay time is adjusted in the broadcasting main station and the plurality of relay stations, and broadcast waves are output simultaneously from the broadcaster at the same timing.

[Outline of Conventional Broadcast Communication System: FIG. 12]
A schematic configuration of a conventional broadcast communication system will be described with reference to FIG. FIG. 12 is an explanatory diagram showing a schematic configuration example of a conventional broadcast communication system.
As shown in FIG. 12, the conventional broadcasting communication system is a multistage relay system including a broadcasting main station, a relay station 1, and a relay station 2.

The main broadcasting station is provided with an STL transmitter (STL TX) 101, which multiplexes and modulates an input audio signal and transmits it as a microwave.
The configuration of the main broadcasting station may be simply referred to as “transmitting device”. Also, the main broadcasting station may be provided with a receiving device similar to the relay station and an FM transmitting device that outputs broadcast waves, but the illustration is omitted here.

The relay station 1 receives the microwave from the main broadcasting station, transmits the microwave to the subsequent relay station 2, adjusts and modulates the delay time of the demodulated signal, and outputs the broadcast wave. is there.
A configuration of the relay station 1 will be described.
The relay station 1 includes an STL receiver (STL RX) 121, a data distributor 122, a TTL transmitter (TTL TX) 123, a delay adjuster 124, and an FM transmitter (FM TX) 125. .
The configuration of the relay stations (relay stations 1 and 2) may be simply referred to as “reception device”.

The STL receiver 121 receives and demodulates the microwaves transmitted from the STL transmitter 101 of the main broadcasting station.
The data distributor 122 distributes the signal received by the STL receiver 121 into a high-frequency signal transmitted to the relay station 2 in the next stage and a baseband signal that is an original audio signal.
The TTL transmitter (TTL TX) 123 remodulates the distributed high-frequency signal and transmits it to the relay station 2 as a microwave.

The delay adjusting device 124 stores a delay time (fixed delay amount D1) set based on information of the transmission path delay measured in advance, and delays the baseband signal by the set delay time D1. And output to the FM transmitter 125. The fixed delay amount is a time for adjusting so that the broadcast wave from each relay station is emitted at the same timing.
The FM transmitter 125 modulates the input baseband signal and emits it as an FM broadcast signal.

In the relay station 1, the microwave received by the STL receiver 121 is demodulated, distributed to the high frequency signal and the baseband signal by the data converter 122, and the high frequency signal is remodulated by the TTL transmitter 123 and transmitted to the relay station 2. Sent.
The baseband signal is output after being delayed by a fixed delay amount D1 by the delay adjusting device 124 and output as an FM broadcast signal from the FM transmitting device 125.

The relay station 2 receives and demodulates the microwave from the relay station 1, adjusts the delay time, and outputs an FM broadcast wave.
The relay station 2 includes an STL receiver 131, a delay adjuster 132, and an FM transmitter 133. The delay adjustment device 132 of the relay station 2 stores a fixed delay amount D2.

  In the relay station 2, the microwave received by the STL receiver 121 is demodulated, the baseband signal is delayed by the fixed delay amount D2 by the delay adjustment device 132, and output to the FM transmitter 133. The FM transmitter 133 Is modulated and output as an FM broadcast signal.

  In this way, by outputting a broadcast wave with an appropriate delay time according to the propagation path delay of each relay station, a broadcast signal is emitted at the same timing, and in the SFN (Single Frequency Network) service area, FM synchronous broadcasting with a single frequency is realized.

[Setting of delay time in conventional broadcasting communication system]
In the conventional broadcast communication system, the propagation path delay amounts of a plurality of relay stations that output FM broadcast waves are measured in advance using a measuring instrument such as an oscilloscope, and the relay station having the largest transmission delay is measured based on the measurement result. However, the delay time of the audio signal of each relay station is determined and set in each delay adjustment device so that it can be output at the same timing.
In the FM transmitter of the main broadcasting station, the time from the output of the microwave to the timing at which the FM broadcast wave is output at each relay station is set in the delay adjusting device.
That is, in the conventional broadcasting communication system, the delay time of the broadcasting main station and each relay station is a fixed value.

However, in STL / TTL that performs airborne transmission using microwaves, there may be a variation in propagation path delay due to fading or the like during propagation.
Further, even in RF transmission using an optical cable, there may be a variation in delay time due to a change in cable length due to a season or temperature change.
In such a case, since the propagation path delay is different from the delay time measured in advance, the output timing of the audio signal is shifted in each relay station, and there is a possibility that synchronous broadcasting cannot be performed.

  In addition, as a broadcasting communication system, there is a configuration in which an optical line is used for communication between the broadcasting main station and the relay station. In this case as well, a fixed delay amount is set at each relay station based on the transmission delay time measured in advance. The broadcast signal is output from each relay station at the same timing.

[Related technologies]
As a prior art of the broadcast communication system, Japanese Patent Application Laid-Open No. 2006-14140 “Delay setting data transmission device, TS-STL / TTL reception broadcasting station terrestrial digital broadcast wave delay time measurement adjustment device, and IF-STL / TTL reception” Broadcasting station terrestrial digital broadcasting wave delay time measuring and adjusting device "(Japan Broadcasting Corporation, Patent Document 1), Japanese Patent Application Laid-Open No. 2006-5615" Single frequency network terrestrial digital broadcasting system, single frequency network synchronization method, and transmission device " (Yonden Corporation, Patent Document 2), Japanese Patent Application Laid-Open No. 2004-320348, “Broadcast Signal Transmission Time Measuring Device and Measuring Method, Transmitting Device and Relay Device Using This Transmission Time Measuring Device, and Delay Time Measurement” Device "(Toshiba Corporation, Patent Document 3), Japanese Patent Laid-Open No. 2003-32207" SFN system for terrestrial digital broadcasting and its Transmission delay control method "(NEC Corporation, Patent Document 4) there is.

  In Patent Document 1, an NSI (Network Synchronization Information) parameter having a relative delay setting data serving as a reference for an adjustment amount of delay time at each broadcasting station of digital terrestrial television broadcasting waves is set as TS (Transport Stream). It is described that control is performed so that broadcast waves are output at the same timing at each broadcasting station by multiplexing the signals and transmitting them.

  In Patent Document 2, in a single frequency network of a terrestrial digital broadcasting system, a TS (Transport Stream) data signal is transmitted from a basic station to a relay station, and a TS signal is returned from the farthest relay station and returned to the basic station. It is described that the delay time is detected, and that each relay station matches the transmission timing in consideration of the detected delay time.

  Patent Documents 3 to 4 describe controlling the timing of transmission signals at a plurality of broadcasting stations in a single frequency network for digital terrestrial television broadcasting.

JP 2006-14140 A JP 2006-5615 A JP 2004-320348 A JP 2003-32207 A

  However, in the conventional broadcasting communication system, since the delay time set in the broadcasting main station and each relay station is a fixed value, it is not possible to follow fluctuations in propagation path delay due to fading and seasonal changes, and synchronous broadcasting. There is a problem that there is a possibility that it becomes impossible.

  The present invention has been made in view of the above situation, and even if there is a variation in propagation path delay due to fading or seasonal change, each relay station always delays an audio signal by an appropriate delay time, An object is to provide a broadcast communication system, a broadcast communication apparatus, and a broadcast communication method that can output broadcast waves from a plurality of relay stations at the same timing.

  The present invention for solving the problems of the conventional example described above is a broadcast communication system that performs synchronous broadcasting using an audio signal transmitted from a transmission device to a reception device as a broadcast signal using the same frequency. Input from the broadcast communication data received from the transmitter and the transmission device that multiplexes and transmits the time information synchronized with the pulse signal obtained from the reference signal of the GPS signal received on the transmission side to the user bits of the broadcast communication data including Separates the audio signal and time information, generates a reception pulse signal synchronized with the time information, and calculates the difference between the reception pulse signal and the reference pulse signal obtained from the reference signal of the GPS signal received at the reception side as the transmission delay time And calculating the difference between the transmission delay time and the reference delay time stored in advance as the timing adjustment time, It is characterized in that a receiving device for Hatsuho audio broadcast signals from delays the input audio signal based.

  The present invention also relates to a broadcast communication apparatus that receives an audio signal transmitted from a transmission apparatus and outputs it as a broadcast signal. In the transmission apparatus, the user bit of the broadcast communication data including the input audio signal is transmitted to the transmission side. Receiving the broadcast communication data transmitted by multiplexing the time information synchronized with the pulse signal obtained from the reference signal of the GPS signal received by the receiver, and separating the input voice signal and the time information; A data restoration unit that generates a synchronized reception pulse signal, a comparison unit that compares the reference pulse signal obtained from the reference signal of the GPS signal received on the reception side with the reception pulse signal, and calculates a difference as a transmission delay time; The difference between the reference delay time stored in advance and the transmission delay time is calculated as the timing adjustment time, and the audio signal is delayed by the timing adjustment time and output. A delay generator that modulates the audio signal delayed, is characterized by comprising an FM transmission unit for outputting as audio broadcasting signal.

  The present invention is also a broadcast communication method in a broadcast communication system that performs synchronous broadcasting using the same frequency as an audio signal transmitted from a transmission device to a reception device, and the transmission device includes an input audio signal. The time information synchronized with the pulse signal obtained from the reference signal of the GPS signal received on the transmission side is multiplexed and transmitted to the user bit of the broadcast communication data, and the reception device receives the input from the broadcast communication data received from the transmission device. Separates the audio signal and time information, generates a reception pulse signal synchronized with the time information, and calculates the difference between the reception pulse signal and the reference pulse signal obtained from the reference signal of the GPS signal received at the reception side as the transmission delay time And calculating the difference between the transmission delay time and the reference delay time stored in advance as the timing adjustment time, Is characterized in that Hatsuho audio broadcast signals from delays the input audio signal based on the between.

  In addition, the present invention is a broadcast communication system that performs synchronous broadcasting using the same frequency as an audio signal transmitted from a transmission device to a reception device, in which time is set in user bits of broadcast communication data including an input audio signal. When writing information, the current time is calculated based on the reference signal of the GPS signal received on the transmission side, and as the time information, the synchronization time stamp indicating the current time and the modulation start time for the broadcast wave on the reception side are specified Based on the reference signal of the GPS signal received on the receiving side, the time when the broadcast communication data is received from the transmitting device is calculated as the receiving time based on the reference signal of the GPS signal received on the receiving side The input audio signal and time information are separated from the broadcast communication data, and the difference between the reception time and the synchronization time stamp included in the time information is calculated as the transmission delay time. A reception device that calculates a difference between a modulation start time stamp and a reception time included in the signal as a timing adjustment time, and delays an input audio signal based on the timing adjustment time and then starts modulation into a broadcast wave. It is characterized by that.

  Further, the present invention is a broadcast communication apparatus that receives an audio signal transmitted from a transmission apparatus and outputs it as a broadcast signal. In the transmission apparatus, time information is added to user bits of broadcast communication data including an input audio signal. The synchronization time stamp indicating the current time calculated based on the reference signal of the GPS signal received on the transmission side when writing and the modulation start time stamp specifying the modulation start time for the broadcast wave on the reception side as time information Based on the GPS signal reference signal received at the receiving side, the receiving unit that receives the broadcast communication data that is multiplexed and transmitted and separates the input audio signal and the time information, the time when the broadcast communication data is received is determined. Included in time information, current time recognition unit that calculates as reception time, transmission time calculation unit that calculates difference between reception time and synchronous time stamp included in time information as transmission delay time Delayed by a timing adjustment time determination unit that calculates a difference between a modulation start time stamp and a reception time as a timing adjustment time, a delay time adjustment unit that delays an input audio signal based on the timing adjustment time, and a delay time adjustment unit And an analog audio conversion unit that converts the audio signal into an analog audio signal and a modulation unit that modulates the analog audio signal into a broadcast wave.

  The present invention is also a broadcast communication method in a broadcast communication system that performs synchronous broadcasting using the same frequency as an audio signal transmitted from a transmission device to a reception device, and the transmission device includes an input audio signal. When writing time information in user bits of broadcast communication data, the current time is calculated based on the reference signal of the GPS signal received on the transmitting side, and as time information, a synchronous time stamp indicating the current time and broadcast on the receiving side A modulation start time mark that specifies the modulation start time for the wave is written and multiplexed and transmitted, and the receiving device receives broadcast communication data from the transmitting device based on the reference signal of the GPS signal received on the receiving side The time is calculated as the reception time, the input audio signal and the time information are separated from the received broadcast communication data, and the difference between the reception time and the synchronization time stamp included in the time information is calculated. Calculate as transmission delay time, calculate the difference between the modulation start time stamp included in the time information and the reception time as timing adjustment time, delay the input audio signal based on the timing adjustment time, and then modulate to the broadcast wave It is characterized by starting.

  According to the present invention, a broadcast communication system that performs synchronous broadcasting using the same frequency as an audio signal transmitted from a transmission device to a reception device, and user bits of broadcast communication data including an input audio signal, A transmission device that multiplexes and transmits time information synchronized with a pulse signal obtained from a reference signal of a GPS signal received on the transmission side, and separates an input audio signal and time information from broadcast communication data received from the transmission device. A reception pulse signal synchronized with time information is generated, and a difference between the reception pulse signal and the reference pulse signal obtained from the reference signal of the GPS signal received at the reception side is calculated as a transmission delay time, and the transmission delay time is stored in advance. The timing difference is calculated as the timing adjustment time, and the input audio signal is delayed based on the timing adjustment delay time. Since it is a broadcasting communication system with a receiving device that emits an audio broadcast signal, even if the transmission delay time fluctuates due to fading or seasonal changes, an appropriate timing adjustment time according to the actual transmission delay time There is an effect that a single frequency FM synchronous broadcast can be realized by outputting broadcast waves from a plurality of relay stations at the same timing.

  In addition, according to the present invention, there is provided a broadcast communication system that performs synchronous broadcasting using an audio signal transmitted from a transmission device to a reception device as a broadcast signal using the same frequency, and a user bit of broadcast communication data including an input audio signal When the time information is written in, the current time is calculated based on the reference signal of the GPS signal received on the transmission side, and as the time information, the synchronization time stamp indicating the current time and the modulation start time on the broadcast wave on the reception side Based on the reference signal of the GPS signal received on the receiving side, the time when the broadcast communication data is received from the transmitting device is calculated as the receiving time based on the transmitting device that writes and multiplexes the modulation start time stamp that designates The input audio signal and time information are separated from the received broadcast communication data, and the difference between the reception time and the synchronization time stamp included in the time information is calculated as a transmission delay time. A reception device that calculates a difference between a modulation start time stamp included in the inter-frame information and a reception time as a timing adjustment time, delays an input audio signal based on the timing adjustment time, and starts modulation into a broadcast wave; Even if the transmission delay time fluctuates due to fading or seasonal changes, an appropriate timing adjustment time can be calculated according to the actual transmission delay time. Therefore, it is possible to realize a single frequency FM synchronous broadcast by outputting a broadcast wave.

  Also, according to the present invention, in audio digital broadcasting, time information is embedded in AES / EBU user bits and transmitted by a transmission device, and the delay time is adjusted based on the time information by a reception device. Can be realized.

1 is a schematic configuration diagram of a broadcast communication system according to a first embodiment of the present invention. It is explanatory drawing which shows the structure of AES / EBU digital audio data. It is explanatory drawing which shows the structure of an AES / EBU digital audio sub-frame. 2 is a configuration block diagram of a transmission device 10. FIG. It is a block diagram which shows the structure of a receiver. It is a schematic explanatory drawing which shows calculation of transmission delay time. It is a block diagram which shows the structure of the receiver in the case of performing multistage relay. It is a block diagram which shows the structure of the receiver using an optical line. It is a structure block diagram of the transmitter AES / EBU data conversion part of the broadcast communication system which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the structure of a 2nd transmitter. It is explanatory drawing which shows the calculation method of the timing adjustment time in a 2nd receiver. It is explanatory drawing which shows the example of schematic structure of the conventional broadcast communication system.

Embodiments of the present invention will be described with reference to the drawings.
[Outline of the embodiment]
In the broadcast communication system and the broadcast communication method according to the embodiment of the present invention, the transmission apparatus of the broadcast main station synchronizes with a pulse signal (1 PPS (Pulse Per Second) signal) once per second obtained from a GPS signal, for example. The time information is multiplexed and transmitted in the user bit area of the AES / EBU audio signal, and the relay station receiver compares the 1PPS signal obtained from the GPS signal with the 1PPS time information extracted from the received signal and transmits it. The delay time is obtained, and based on the transmission delay time, the time up to a preset reference delay time is calculated as the timing adjustment time, and the audio signal extracted from the received signal is delayed by the timing adjustment time and modulated. Even if the transmission delay time fluctuates due to fading or seasonal changes, an appropriate timing is Adjustment time can be calculated, and broadcast waves can be output from a plurality of relay stations at the same timing to realize the best single frequency FM synchronous broadcasting.

  In the broadcast communication system and the broadcast communication method according to the embodiment of the present invention, the transmission device generates synchronization time information indicating a transmission time based on, for example, a 1 PPS pulse signal (1 PPS signal), and the synchronization time information and The modulation start time for the FM broadcast wave is multiplexed with the user bit area of the AES / EBU audio signal and transmitted, and the receiving device of the relay station extracts it from the current time and the received signal obtained from the 1PPS signal obtained from the GPS signal. The transmission delay time is obtained by comparing with the synchronized time information, and the time from the current time to the received modulation start time is calculated as the timing adjustment time, and the audio signal extracted from the received signal is delayed by the timing adjustment time. Modulated and output as a broadcast wave, even if the transmission delay time fluctuates due to fading or seasonal changes Following this, an appropriate timing adjustment time can be calculated to realize the best single frequency FM synchronous broadcasting, and the modulation start time can be adjusted by feeding back the calculated transmission delay time to the broadcasting main station. The system maintenance management can be facilitated.

[First Embodiment: FIG. 1]
A broadcast communication system (first system) according to a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic configuration diagram of a broadcast communication system according to the first embodiment of the present invention.
As shown in FIG. 1, the first system includes a broadcasting main station, a relay station (1), and a relay station (2).
In the first system, the broadcasting main station is provided with the transmitting device 10, the relay station (1) is provided with the receiving device 20 and the FM transmitting device 200, and the relay station (2) is provided with the receiving device 30 and the FM transmitting device. 300 is provided.
Each of the transmission device 10 and the reception devices 20 and 30 is provided with a GPS reception unit, and receives the same reference timing.

As a feature of the first system, the transmission device 10 multiplexes the time information generated based on the GPS signal on the audio signal of AES / EBU and transmits it by microwave.
As described later, the time information is information synchronized with the 1PPS signal generated from the GPS signal.

Further, as a feature of the first system, a delay reference time is set in advance in the receiving device 20 of each relay station.
In the first system, the notification timing is set in consideration of the transmission delay time of the farthest relay station (2), and the time from the voice signal output from the transmitter 1 to the notification timing is set. Is stored in the receivers 20 and 30 as a delay reference time.
Here, the delay reference time is 2000 μs.

The receiving device 20 transmits the microwave received from the transmitting device 10 to the receiving device 30, and based on the time information extracted from the received signal and the 1 PPS reference signal generated by itself based on the GPS signal. The transmission delay time is obtained, and further, the delay time is adjusted in order to synchronize the timings of notification from all the FM transmitters, and the audio signal is output to the FM transmitter 200.
The FM transmitter 200 modulates the audio signal and outputs it as an FM broadcast signal.

The receiving device 30 receives the microwave from the receiving device 20, extracts time information and an audio signal, obtains a transmission delay time, adjusts the delay time, and outputs the audio signal to the FM transmitting device 300.
The FM transmitter 300 modulates the audio signal and outputs it as an FM broadcast signal.

  By adjusting the timing of outputting the audio signal to the FM transmitter in the receivers 20 and 30, it is possible to match the timing of the notification in the FM transmitters 200 and 300.

[Adjustment of delay time in the first system]
The adjustment of the delay time in the first system will be described.
The receiving device 20 calculates the transmission delay time (S2-S1, for example, 500 μs) based on the time information (S1) of the transmitting device and the timing (S2) of the 1PPS signal generated by itself.
Then, the timing adjustment time is calculated by subtracting the transmission delay time from the preset delay reference time (2000 μs).
Here, 2000−500 = 1500 μs, and the receiving apparatus 20 delays the audio signal by 1500 μs and outputs it to the FM transmitting apparatus 200.

Similarly, the receiving device 30 obtains the transmission delay time (S3-S1, for example, 1000 μs) from the time information (S1) of the transmitting device and the timing (S3) of the 1PPS signal generated by itself, and sets 2000−1000 = 1000 μs. Calculated as timing adjustment time.
That is, the receiving device 30 delays the audio signal by 1000 μs and outputs it to the FM transmitting device 300.

  In this way, in the first system, by calculating the timing adjustment time each time transmission is performed from the transmission device, it is possible to cope with changes in transmission delay time due to transmission channel fading, etc. Timing synchronization can be achieved.

[AES / EBU digital audio data structure: FIG. 2]
Next, the structure of AES / EBU digital audio data used in the first system will be described with reference to FIG. FIG. 2 is an explanatory diagram showing the structure of AES / EBU digital audio data. The AES / EBU data corresponds to the broadcast communication data in the claims.

As shown in FIG. 2, the AES / EBU signal is composed of 192 audio frames (frame 0 to frame 191) with one audio block as one unit.
One audio frame is composed of two 32-bit audio subframes, and is referred to as subframe A and subframe B. In the case of a stereo signal, audio data of the L channel and the R channel are stored.

[AES / EBU digital audio subframe structure: FIG. 3]
Next, the AES / EBU digital audio subframe structure will be described with reference to FIG. FIG. 3 is an explanatory diagram showing the structure of an AES / EBU digital audio subframe.
The subframe is composed of seven areas: preamble, auxiliary data, audio data word, valid bit, user bit, channel status bit, and parity bit.

Data in each area will be described.
The preamble (synchronization word) is data indicating the start of a new frame, and is composed of 4 bits. This preamble is a bit sequence that serves as a flag for the start of the audio block, the start of subframe A other than the start of the audio block, and the start of subframe B, respectively.

The auxiliary data can be used as an audio data word, but is 4-bit data used for transmission of a narrow band audio signal, for example, communication between studios.
The audio data word is data in which a main line audio signal is stored, and can be assigned up to 24 bits by using 4-bit auxiliary data.

The valid bit is data (1 bit) indicating whether the data is valid or invalid.
Setting it to “0” indicates that the audio data word is valid data that can be D / A converted, and setting it to “1” allows the receiving side to mute the audio signal.

The user bit is data (1 bit) that can be freely used by the user. In the present system, time information based on the 1PPS signal is stored therein.
The user bit data is sent to the memory array of 8 bits (1 byte) × 24 columns by the receiving device. In this memory array, 192 bits are stored in order of frame number from the start of the audio block for each subframe.

  The receiving devices 20 and 30 of the first system store user bits in a memory array, analyze them, and read time information input by the transmitting device 10. The operations of the transmission device 10 and the reception devices 20 and 30 will be described later.

The channel status bit is data (1 bit) in which information such as emphasis, category code, and copy prohibition flag is stored. Similarly to the user bit, 8 bits (1 byte) × 24 columns of memory in the receiving device. Stored in the array.
The parity bit (1 bit) is data for displaying even parity and detecting an odd number of transmission errors.

[Configuration of Transmitter 10: FIG. 4]
Next, the configuration of the transmission apparatus 10 provided in the broadcasting main station will be described with reference to FIG. FIG. 4 is a configuration block diagram of the transmission device 10.
As illustrated in FIG. 4, the transmission device 10 includes a GPS reception unit, a reference signal generation unit 11, an AES / EBU data conversion unit 12, and an STL transmission device 13.
The GPS receiving unit receives a GPS signal.
The reference signal generator 11 generates a reference pulse (1PPS signal) synchronized with the GPS signal.

The AES / EBU data conversion unit 12 generates time information in the transmission device based on the reference signal.
Specifically, the AES / EBU data converter 12 converts the bit of the user bit area of the AES / EBU signal of the audio frame to “1” at the timing of receiving the 1PPS signal with the 1PPS signal as a trigger.

That is, the AES / EBU data conversion unit 12 embeds time information that becomes “1” in synchronization with the transmission side pulse signal in the user bits of the AES / EBU frame.
In the first system, this is used as delay difference detection for adjusting the delay amount on the receiving side.
The STL transmitter 13 multiplexes and modulates an AES / EBU signal including a frame in which user bits are converted, and transmits the multiplexed signal to the relay station (1) through the micro line.

[Configuration of receiving apparatus: FIG. 5]
Next, the configuration of the receiving apparatus will be described with reference to FIG. FIG. 5 is a block diagram showing the configuration of the receiving apparatus.
Here, the configuration of a receiving apparatus that does not relay to another relay station is shown, and corresponds to the configuration of the relay station (2) shown in FIG. Here, although described as a relay station (2), the relay station (1) also has a configuration substantially equivalent to that in FIG.

As shown in FIG. 5, the receiving device includes a TTL receiving device 31, an AES / EBU data restoring unit 32, a GPS receiving unit, a reference signal generating unit 33, a delay adjusting device 34, and an FM transmitting device 35. I have.
The relay station (1) includes an STL receiver instead of the TTL receiver 31 in order to receive a signal from the transmitter 10.

The TTL receiver 31 receives the microwave from the relay station (1), demodulates it, and separates the ABS / EBU signal.
The ABS / EBU data restoration unit 32 stores the user bits of the ABS / EBU data in the memory array, analyzes the time information, and outputs the audio signal to the delay adjustment device 34 described later.

The analysis of time information will be described.
The ABS / EBU data restoring unit 32 of the receiving device scans the memory array, generates a pulse triggered by a flag whose user bit is “1”, and outputs the pulse to the delay adjusting device 34.
The pulse signal output from the ABS / EBU data restoration unit 32 is a signal synchronized with the 1PPS signal generated by the transmission apparatus 10, but is a 1PPS signal in which a delay is caused by transmission.
Here, the timing of the 1PPS signal from the ABS / EBU data restoration unit 32 is S2. The 1PPS signal from the ABS / EBU data restoration unit 32 corresponds to the reception pulse signal recited in the claims.

The GPS receiving unit receives GPS signals.
The reference signal generator 33 generates a reference pulse signal (1PPS signal) synchronized with the GPS signal. Here, the timing of the 1PPS signal generated on the receiving side is S1.
The delay adjustment device 34 adjusts the timing at which the audio signal is output to the FM broadcaster, and includes a comparison unit 341 and a delay generation unit 342.

The comparison unit 341 compares the 1PPS signal from the reference signal generation unit 33 with the 1PPS signal from the AES / EBU data restoration unit 32, and determines the difference between the timings S2 and S1 (S2−S1) as a transmission delay time (propagation). (Path delay, delay amount).
As will be described later, since the time information from the transmission device 10 is stored as it is even if it is relayed on the way, the reception device at the end until the reception device receives it from the transmission device 10 via the relay station. The transmission delay time can be calculated.

In the above example, the ABS / EBU data restoring unit 32 of the receiving device generates a pulse, the pulse signal is defined as a received pulse signal, and compared with a reference pulse signal synchronized with the GPS signal in the reference signal generating unit 33. However, both the case where the pulse signal is generated and compared as an analog signal or the case where the pulse signal is generated and compared as a digital signal are conceivable.
For example, when the reception pulse signal is generated as a digital signal in the ABS / EBU data restoration unit 32 of the reception apparatus, the reference pulse signal synchronized with the GPS signal in the reference signal generation unit 33 is converted into a digital signal. If it is generated as a signal, it is compared as digital data. That is, each pulse signal only needs to be able to compare the respective signals.

The delay generation unit 342 calculates a timing adjustment time based on the transmission delay time calculated by the comparison unit 341 and a preset delay reference time, and timings the audio signal from the AES / EBU data restoration unit 32. The output is delayed to the adjustment time and output to the FM transmitter 35.
As a result, the receiving device can delay the signal received by the micro line by the timing delay time and output it as an FM broadcast wave, and all the receiving devices emit the broadcast wave at the same timing.

The operation of the receiving apparatus will be described with reference to FIG.
In the receiving apparatus, the time information written by the transmitting apparatus is extracted by the AES / EBU data restoring unit 32 from the signal received from the micro line by the TTL receiving apparatus 31, and the 1PPS signal generated based on the extracted time information is the delay adjusting apparatus. 34 is input to the comparison unit 341.

The comparison unit 341 compares the timing S1 of the 1PPS signal from the reference signal generation unit 33 with the timing S2 of the 1PPS signal (reception pulse signal) generated from the reception signal, and calculates the transmission delay time S2-S1.
Then, in the delay generation unit 342, the delay reference time-transmission delay time is calculated as the timing adjustment time, and the audio signal is delayed by the timing adjustment time, output to the FM transmitter 35, and output as a broadcast wave.
In this way, the operation of the receiving apparatus is performed.

[Calculation of transmission delay time: Fig. 6]
Here, the calculation of the transmission delay time will be described with reference to FIG. FIG. 6 is a schematic explanatory diagram illustrating calculation of transmission delay time.
As shown in FIG. 6, when the 1PPS signal generated by the reference signal generation unit 33 of the receiving apparatus is compared with the 1PPS signal (reception pulse signal) from the AES / EBU data restoration unit 32, the timing S2 is a propagation path delay. Is delayed compared to S1.
When the comparison unit 341 receives the 1PPS signal from the reference signal generation unit 33, it holds the timing of S1, and when it receives the 1PPS signal from the AES / EBU data restoration unit 32, it holds the timing of S2 and delays transmission. The time is calculated as S2-S1.

As another method, the comparison unit 341 starts counting by using the 1PPS signal generated by the reference signal generation unit 33 as a trigger, and ends counting when receiving the 1PPS signal from the AES / EBU data restoration unit 32. The transmission delay time may be calculated based on the count value.
The calculation of the transmission delay time may be performed by any method.

  In this system, the transmission delay time is calculated every second, so even if the transmission delay time fluctuates due to the effects of fading, the actual transmission delay time can be calculated accurately each time. By delaying the audio signal by the delay time, good FM synchronous broadcasting can be realized.

[Configuration of receiving apparatus for multistage relay: FIG. 7]
Next, the configuration of the receiving apparatus when performing multistage relay will be described with reference to FIG. FIG. 7 is a block diagram showing the configuration of the receiving apparatus when performing multistage relaying, and shows the configuration of the relay station (1) shown in FIG.
As shown in FIG. 7, the receiving apparatus of the relay station (1) is configured to perform a receiving operation equivalent to the receiving apparatus of the relay station (2) shown in FIG. 5, and the STL receiving apparatus 21 and the AES / EBU data. The data distribution unit 26 includes a restoration unit 22, a GPS reception unit, a reference signal generation unit 23, a delay adjustment device 24, and an FM transmission device 25, and further performs a relay operation to a subsequent relay station. And a TTL transmitter 27.
The description of the same components as in FIG. 5 is omitted.
Note that, also in a receiving apparatus that performs multistage relay, the timing adjustment time is calculated and the output timing of the broadcast wave is adjusted in the same manner as the receiving apparatus shown in FIG.

The STL receiver 21 receives the microwave from the transmitter 10.
The data distribution unit 26 distributes the signal received by the STL reception device 21 into two, one output to the AES / EBU data restoration unit 22 and the other output to the TTL transmission device 27.
In the data distribution unit 26, user bits are distributed and transmitted together with the audio signal.
That is, the time information from the transmission device 10 is stored as it is and transmitted to the relay station at the subsequent stage.
The receiving device of the relay station (1) does not embed time information indicating the timing of the 1PPS signal generated by itself, like the transmitting device 10 of the transmitting main station.

The TTL transmitter 27 modulates the distributed signal including user bits and transmits the modulated signal to a subsequent relay station via a micro line.
In the subsequent relay station, as described with reference to FIG. 5, the delay adjustment device compares the reference signal generated by itself with the time information analyzed by the AES / EBU data restoration unit, and adjusts the timing. By calculating the time, it is possible to delay the audio signal by an appropriate delay time and output the broadcast wave.
As described above, in the first system, FM synchronous broadcasting can be realized as a configuration in which relaying is performed over a plurality of stages.

[Configuration of receiving apparatus using optical line: FIG. 8]
Depending on the broadcasting station, in order to improve the reliability of broadcasting, there is a case where not only a micro line but also an optical line is provided to make a duplex system, and AES / EBU data is transmitted through the optical line.
In such a case, for example, normally, broadcasting is performed using a signal from the micro line, but if a failure occurs and the microwave signal cannot be normally received, the signal received on the optical line is used. Broadcasting is realized.

A configuration of a receiving apparatus using an optical line will be described with reference to FIG. FIG. 8 is a block diagram showing the configuration of a receiving apparatus using an optical line.
As shown in FIG. 8, the receiver using the optical line includes an optical signal receiver 46 and an AES / EBU switch 47 in addition to the configuration of the receiver using the micro line shown in FIG. ing.
Note that the timing adjustment time calculation method for adjusting the output timing of the audio signal is the same as that of the receiving apparatus shown in FIG.

A characteristic part of a receiving apparatus using an optical line will be described.
The optical signal receiver 46 converts the optical signal received via the optical line into an electrical signal and demodulates it.
The AES / EBU switch 47 monitors the received signal from the STL receiver 41. If the synchronization signal is received normally, the AES / EBU switch 47 outputs the AES / EBU signal from the STL receiver 41 and receives it normally. If not, the signal is switched to the signal from the optical signal receiving unit 46, and the AES / EBU signal received via the optical line is output.

As a result, even when a failure occurs in the wireless line, the AES / EBU signal from the optical line that is the standby line can be received, and broadcasting can be normally performed.
Even in a receiving device using an optical line, the delay adjusting device 44 accurately calculates the timing adjustment time based on the time information of the AES / EBU signal received via the optical line, and appropriately delays the audio signal. And output to the FM transmitter to realize FM synchronous broadcasting.

[Second Embodiment]
Next, a broadcast communication system (second system) according to the second embodiment of the present invention will be described.
The second system multiplexes the time when the process of embedding the time information in the transmission data and the modulation start time at the reception apparatus provided in each relay station are multiplexed into the audio data as time information. This is transmitted, and the timing for starting modulation of the audio signal is adjusted by the receiving device of each relay station.

[Configuration of Second Transmitting Device: FIG. 9]
The characteristic part of the transmission apparatus (second transmission apparatus) in the second system will be described with reference to FIG. FIG. 9 is a configuration block diagram of a transmission device AES / EBU data conversion unit of the broadcast communication system according to the second embodiment of the present invention.
As illustrated in FIG. 9, the second transmission device includes a GPS reception unit, a reference signal generation unit 51, and an AES / EBU data conversion unit 52. In FIG. 9, transmission means such as an STL transmitter and an optical transmitter that transmit signals are omitted.

Each unit of the second transmission device will be described.
The GPS receiving unit receives a GPS signal.
The reference signal generator 51 generates a 1PPS signal as a reference signal synchronized with the received GPS signal (3A).

The AES / EBU data conversion unit 52 includes an AES / EBU conversion unit 53, a time information addition unit 54, a synchronization time stamp generation unit 55, and a modulation start time stamp generation unit 56.
The AES / EBU converter 53 converts the input audio signal (3A) into the AES / EBU audio data (3B) shown in FIGS.
The time information adding unit 54 multiplexes the AES / EBU signal (3B) with a synchronization time stamp (to be described later) and a modulation start time stamp (3F) and outputs the multiplexed signal to the transmission means.

The synchronization time stamp generator 55 is a characteristic part of the second transmission device, and generates current time information (synchronization time stamp) to be added to the transmitted AES / EBU signal.
The synchronization time stamp is information indicating the time when the time information is written by the AES / EBU data conversion unit 52 for each audio block, and can be regarded as the transmission time.
The synchronization time stamp generator 55 counts the elapsed time from the rise of the 1PPS signal (3C) from the reference signal generator 51, generates a synchronization time stamp (3D), and periodically (always) adds time information. To the unit 54 and the modulation start time stamp generator 56.

The modulation start time stamp generation unit 56 is also a characteristic part of the second transmission device, and generates modulation start time information based on delay time setting information set from the outside.
Specifically, the modulation start time stamp generation unit 56 adds the delay time based on the delay time setting information (3E) to the synchronization time stamp from the synchronization time stamp generation unit 55 as the modulation start time, It outputs to the time information addition part 54 as a modulation | alteration start time stamp (3G).

  The modulation start time stamp is information indicating the time at which modulation for broadcasting is started in each relay station, and is information common to all relay stations. In the second system, the modulation start time stamp is designated from the broadcasting main station side each time, and can be adjusted according to the actual condition of the transmission path.

  The delay time setting information is information that can be arbitrarily set by the system administrator. In the second system, information on the transmission delay time can be collected from the receiving apparatus, and appropriate delay time setting information can be set based on the collected information. Is. This will be described later.

  When the AES / EBU data (3B) is input from the AES / EBU converter 53, the time information adding unit 54 reads the synchronization time stamp and the modulation start time stamp, and synchronizes with the user bits in units of one audio block. Write the time stamp.

Here, in the second transmission device, the synchronization time stamp and the modulation start time stamp are written using the user bits of one audio block (192 bits).
As a result, information on the time at which the audio block was processed by the transmission device (transmission time information) and the time at which the audio block should be modulated by the reception device is added to the audio data.

  Then, an AES main line signal (3F) in which the synchronization time stamp and the modulation start time stamp are multiplexed on the audio signal is generated and transmitted to the reception device by the STL transmission device or the optical signal transmission device.

[Configuration of Second Receiver: FIG. 10]
Next, a receiving device (second receiving device) in the second broadcast communication system will be described with reference to FIG. FIG. 10 is a configuration block diagram showing the configuration of the second transmission device.
As shown in FIG. 10, the second receiving device includes a GPS receiving unit, a reference signal generating unit 61, and a simultaneous broadcast modulator 62. A broadcaster is provided at the output stage of the modulation unit 69, but is omitted here. Similarly, reception means corresponding to the transmission means of the transmission apparatus is provided, but is omitted.

  The reference signal generator 61 generates a 1PPS signal synchronized with the GPS signal based on the GPS signal received by the GPS receiver.

  The simultaneous broadcast modulator 62 further includes an AES / EBU time information extraction unit 63, a current time recognition unit 64, a transmission time calculation unit 65, a timing adjustment time determination unit 66, and a delay time adjustment unit 66. , An AES / EBU analog voice converter 68 and a modulator 69 are provided.

The AES / EBU time information extraction unit 63 transmits a synchronization time stamp and a modulation start time stamp embedded in the transmission device from the AES main line signal (3E) transmitted by wired or wireless transmission means and received and demodulated by the reception unit. Take out.
The AES / EBU time information extraction unit 63 then outputs the synchronization time stamp (4C) to the transmission time calculation unit 65 and outputs the modulation start time stamp (4E) to the timing adjustment time determination unit 66.
Note that the audio signal separated from the AES main line signal is output to the delay time adjustment unit 67.

  The current time recognizing unit 64 calculates the elapsed time from the rising edge of the 1PPS signal to the present time based on the 1PPS signal generated by the reference signal generating unit 61, with the rising edge of the 1PPS signal as time 0. It outputs to the transmission time calculation part 65 as information (4J). The current time information corresponds to the reception time described in the claims.

The transmission time calculation unit 65 calculates a transmission delay time based on the current time information and the synchronization time stamp.
Specifically, since the synchronization time stamp indicates the time at the time of transmission and the current time information indicates the time at the time of reception, the difference between the two (current time information−synchronization time stamp) is the transmission delay time. . As will be described later, the transmission delay time is fed back periodically from the receiving apparatus to the transmitting apparatus, for example, and used for system maintenance management.
Also, the transmission time calculation unit 65 outputs the current time information as it is to the timing adjustment time determination unit 66.

The timing adjustment time determination unit 66 performs timing based on the current time information (4J) output from the transmission time calculation unit 65 and the modulation start time stamp (4E) output from the AES / EBU time information extraction unit 63. Calculate the adjustment time.
The timing adjustment time is a time indicating how much the audio signal should be delayed in order to modulate it to the modulation start time set by the modulation start time stamp. The calculation of the timing adjustment time will be described later.

  The delay time adjustment unit 67 delays the input AES / EBU audio data in accordance with the timing adjustment time output from the timing adjustment time determination unit 66 (4F), and outputs it to the AES / EBU analog audio conversion unit 68.

The AES / EBU analog voice converter 68 converts the input voice data into an analog voice signal (4G).
The modulator 69 modulates the analog audio signal and outputs it as an FM broadcast wave (4H).

[Method for calculating timing adjustment time in second receiver: FIGS. 9, 10, and 11]
Next, a method for calculating the timing adjustment time in the second receiving apparatus will be described with reference to FIGS. FIG. 11 is an explanatory diagram illustrating a method of calculating the timing adjustment time in the second receiving apparatus.
FIG. 11A shows a 1PPS signal generated based on the GPS signal. This signal is generated as a reference signal with the same timing in both the main broadcasting station and the relay station.

Then, as shown in FIG. 11 (b), in the second transmission device, the AES / EBU signal (3B in FIG. 9) is input to the time information adding unit 54 at time t1 after the rising of 1PPS. A synchronization time stamp (3D in FIG. 9) is embedded as a modulation synchronization signal in the audio block of AES / EBU. That is, the information on the synchronization time stamp (information corresponding to the transmission time) is time t1.
At that time, a modulation start time stamp (time tm) for designating when modulation is to be started on the receiving apparatus side is also embedded.

  The second receiving apparatus receives the AES main line signal (3E in FIG. 10) through different delay times generated by the respective transmission paths. The current time recognition unit 64 recognizes the time t2 at that time as the reception time. Since the time t2 varies depending on the state of the transmission path, the time varies at each receiving apparatus.

Then, the transmission time calculation unit 65 calculates t2−t1 as the transmission delay time.
Further, the timing adjustment unit 66 calculates the timing adjustment time as tm−t2.
In each receiving apparatus, the delay time adjusting unit 67 delays the audio signal by the timing adjustment time (tm−t2) and then starts modulation, so that all receiving apparatuses emit the same audio signal at the same time tm. Is something that can be done.
Thereby, the modulator for synchronous broadcasting in a plurality of receiving apparatuses can output signals received via different transmission paths at the same time tm, and can realize synchronous broadcasting.

Note that the transmission delay time calculated by the transmission time calculation unit 65 is not directly used for calculating the timing adjustment time, but is fed back from the relay station to the broadcast main station and used for adjustment of broadcast communication.
For example, at the time of system operation start, it turns out that the transmission delay time received from the relay station is not so long even when sufficiently long delay time setting information is set in the broadcasting main station and the modulation start time tm is set to a considerably late time. In this case, the delay time setting information can be set to a shorter time, and the modulation start time tm can be set to an earlier time.
In this way, it is possible to finely adjust the broadcast communication by reflecting the actual transmission path conditions.

[Effect of the embodiment]
According to the broadcast communication system, the broadcast communication apparatus, and the broadcast communication method according to the first embodiment of the present invention, the transmission side 1PPS generated by the transmission apparatus in the user bit area of the AES / EBU audio signal in the transmission apparatus. The time information synchronized with the signal is multiplexed and transmitted, and the receiving device extracts the time information from the received signal, generates a 1PPS signal synchronized with the time information as a received 1PPS signal, and the received 1PPS signal and itself are GPS signals. The transmission delay time is obtained based on the difference from the 1PPS signal generated based on the timing, the timing adjustment time is calculated by subtracting the transmission delay time from the preset reference delay time, and the audio signal is delayed by the timing adjustment time. Output to the FM transmitter after that, even if the propagation path conditions fluctuate due to fading or seasonal changes. The effect of tracking to be calculated with high accuracy transmission delay time in accordance with the actual situation, it is possible to realize a synchronous broadcast to output broadcast waves at the same timing in the plurality of relay stations.

  Moreover, according to the broadcast communication system, the broadcast communication apparatus, and the broadcast communication method according to the second embodiment of the present invention, in the transmission apparatus, the synchronization time indicating the transmission time in the user bit area of the AES / EBU audio signal And a modulation start time stamp that specifies the modulation start time in the receiving device are transmitted and the reception device calculates the transmission delay time from the difference between the reception time and the received synchronization time stamp, and receives the modulation start. Since the timing adjustment time is calculated from the difference between the time stamp and the reception time and the audio signal is delayed by the timing adjustment time and then modulated into the FM broadcast wave, even if the propagation path condition fluctuates Accordingly, it is possible to calculate a transmission delay time with high accuracy following the above, and to achieve a synchronous broadcast in which a plurality of relay stations output broadcast waves at the same timing.

  Further, according to the second system, since the receiving device feeds back the calculated transmission delay time to the transmitting device, the system administrator adjusts the delay time setting information based on the transmission delay time. Therefore, there is an effect that better broadcast communication can be realized according to the actual state of the propagation path.

  Even if there is a change in propagation path delay due to fading or seasonal change, the present invention always delays an audio signal by an appropriate delay time at each relay station, and broadcast waves from the broadcasting main station and a plurality of relay stations at the same timing. Is suitable for a broadcast communication system, a broadcast communication apparatus, and a broadcast communication method.

  DESCRIPTION OF SYMBOLS 10 ... Transmitting device, 11, 23, 33, 43, 51, 61 ... Reference signal generating unit, 12 ... AES / EBU data converting unit, 13, 101 ... STL transmitting device, 20, 30 ... receiving device 21, 41, 121 ... STL receiving device 31, 131 ... TTL receiving device 22, 32, 42 ... AES / EBU data restoration unit 24, 34, 44 ... Delay adjustment device 241, 341, 441 ... comparison unit 242, 342, 442 ... delay generation unit 25, 35, 45, 125, 133, 200, 300 ... FM transmitter 26. Data distribution unit, 27, 123 ... TTL transmission device, 46 ... Optical signal reception unit, 47 ... AES / EBU switch, 52 ... AES / EBU data conversion unit, 53 ... AES / EBU conversion unit, 54 ... time information addition unit, 55 ... synchronous time stamp generation unit, 56 ... modulation start time stamp generation unit, 62 ... synchronous broadcast modulator, 63 ... AES / EBU time information extraction unit, 64 ... current time recognition unit, 65 ... transmission time calculation unit, 66 ... Timing adjustment time determination unit, 67 ... Delay time adjustment unit, 68 ... AES / EBU analog voice conversion unit, 69 ... Modulation unit, 122 ... Data distribution unit, 124, 132 ... Delay adjustment device

Claims (6)

A broadcast communication system that performs synchronous broadcasting using the same frequency as an audio signal transmitted from a transmission device to a reception device,
A transmission device that multiplexes and transmits time information synchronized with a pulse signal obtained from a reference signal of a GPS signal received on the transmission side to user bits of broadcast communication data including an input audio signal;
From the broadcast communication data received from the transmission device, the input audio signal and the time information are separated, a reception pulse signal synchronized with the time information is generated, and obtained from a reference signal of a GPS signal received on the reception side A difference between the received pulse signal and a reference pulse signal is calculated as a transmission delay time, a difference between the transmission delay time and a reference delay time stored in advance is calculated as a timing adjustment time, and based on the timing adjustment delay time. A broadcast communication system comprising: a receiving device that emits an audio broadcast signal after delaying the input audio signal. A broadcast communication device that receives an audio signal transmitted from a transmission device and outputs it as a broadcast signal,
In the transmission device, broadcast communication data transmitted by multiplexing time information synchronized with a pulse signal obtained from a reference signal of a GPS signal received on the transmission side to user bits of broadcast communication data including an input audio signal is received. A receiving unit that separates the input audio signal and the time information;
A data restoration unit for generating a reception pulse signal synchronized with the time information;
A comparison unit that compares the received pulse signal with a reference pulse signal obtained from a reference signal of a GPS signal received on the receiving side, and calculates a difference as a transmission delay time;
Calculating a difference between a reference delay time stored in advance and the transmission delay time as a timing adjustment time, and delaying and outputting the audio signal by the timing adjustment time; and
A broadcast communication apparatus comprising: an FM transmitter that modulates the delayed audio signal and outputs the modulated audio signal as an audio broadcast signal. A broadcast communication method in a broadcast communication system for performing synchronous broadcasting using the same frequency as an audio signal transmitted from a transmission device to a reception device,
The transmission device multiplexes and transmits time information synchronized with a pulse signal obtained from a reference signal of a GPS signal received on the transmission side to user bits of broadcast communication data including an input audio signal,
The receiving device separates the input audio signal and the time information from the broadcast communication data received from the transmitting device, generates a reception pulse signal synchronized with the time information, and receives the GPS signal received on the receiving side. A difference between the received pulse signal and a reference pulse signal obtained from a reference signal is calculated as a transmission delay time, and a difference between the transmission delay time and a reference delay time stored in advance is calculated as a timing adjustment time. A broadcast communication method characterized by emitting an audio broadcast signal after delaying the input audio signal based on a delay time. A broadcast communication system that performs synchronous broadcasting using the same frequency as an audio signal transmitted from a transmission device to a reception device,
When writing time information into user bits of broadcast communication data including an input audio signal, a current time is calculated based on a reference signal of a GPS signal received on the transmission side, and a synchronization time indicating the current time as the time information A transmitter for writing and multiplexing a mark and a modulation start time mark for specifying a modulation start time for a broadcast wave on the receiving side; and
Based on the GPS signal reference signal received on the receiving side, the time when the broadcast communication data is received from the transmitter is calculated as the reception time, and the input audio signal and the time information are separated from the received broadcast communication data. The difference between the reception time and the synchronization time stamp included in the time information is calculated as a transmission delay time, and the difference between the modulation start time stamp included in the time information and the reception time is calculated as a timing adjustment time. A broadcast communication system comprising: a reception device that starts modulation to a broadcast wave after delaying the input audio signal based on the timing adjustment time. A broadcast communication device that receives an audio signal transmitted from a transmission device and outputs it as a broadcast signal,
In the transmission device, a synchronization time stamp indicating a current time calculated based on a reference signal of a GPS signal received on the transmission side when writing time information in user bits of broadcast communication data including an input audio signal, and a reception side A receiving unit that receives broadcast communication data transmitted by multiplexing and transmitting a modulation start time stamp that specifies a modulation start time for a broadcast wave, and separating the input audio signal and the time information;
Based on a GPS signal reference signal received on the receiving side, a current time recognizing unit that calculates the reception time of the broadcast communication data as a reception time;
A transmission time calculation unit that calculates a difference between the reception time and the synchronization time stamp included in the time information as a transmission delay time;
A timing adjustment time determination unit that calculates a difference between the modulation start time stamp included in the time information and the reception time as a timing adjustment time;
A delay time adjustment unit that delays the input audio signal based on the timing adjustment time;
An analog audio conversion unit that converts the audio signal delayed by the delay time adjustment unit into an analog audio signal;
A broadcast communication apparatus comprising: a modulation unit that modulates the analog audio signal into a broadcast wave. A broadcast communication method in a broadcast communication system for performing synchronous broadcasting using the same frequency as an audio signal transmitted from a transmission device to a reception device,
When the transmission device writes time information in user bits of broadcast communication data including an input audio signal, it calculates a current time based on a reference signal of a GPS signal received on the transmission side, and as the time information, the current Write a synchronization time stamp indicating the time and a modulation start time stamp that specifies the modulation start time to the broadcast wave on the receiving side, and multiplex and transmit,
Based on the GPS signal reference signal received on the receiving side, the receiving device calculates a time when the broadcast communication data is received from the transmission device as a reception time, and the input audio signal and the input signal are calculated from the received broadcast communication data. The time information is separated, the difference between the reception time and the synchronization time stamp included in the time information is calculated as a transmission delay time, and the difference between the modulation start time stamp included in the time information and the reception time is timingd A broadcast communication method characterized by calculating as an adjustment time and delaying the input audio signal based on the timing adjustment time and then starting modulation into a broadcast wave.

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