JPH0832596A - Broadcast communication system and its terminal on transmission and reception side - Google Patents

Abstract

PURPOSE:To suppress increase in number of times of re-transmission even when an arrival rate is reduced by sending a packet storing same data repetitively plural times and allowing a reception terminal to validate one of duplicate data and to abort the other as an invalid packet. CONSTITUTION:An arithmetic unit 2 gives transmission data prepared in a temporary storage device to a parallel serial converter 5 according to the procedure stored in a storage device 3. The converter 5 converts received parallel data into serial data and inserts the converted data to a packet, a modulator 6 conversion the data into a signal that can be sent and the signal is sent from an antenna 7 plural times. A demodulator 9 of a receiver side converts the packet received at an antenna 7 into a signal processed by a terminal and gives the signal to a serial parallel converter 8. The converter 8 converts the serial data in the received packet into parallel data and gives them to the arithmetic unit 2. The unit 2 checks whether or not the content of the data is the same as that of the data received precedingly while referencing the storage content of the device 4 according to the procedure stored in the device 3. When the content is not the same, the data are processed as valid data. When the same, the data are aborted as invalid data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a broadcast communication system and is applied to, for example, an HT (Handy Terminal), a POS, a personal computer and the like, which uses wireless data.

[0002]

2. Description of the Related Art First, FIG. 29 and FIG. 30 are explanatory views showing a normal communication method which is not broadcast and a conventional broadcast communication method, respectively, and terminals A, B, C, and C which can communicate with each other. There are four terminals of D, and the data of the same content from the terminal A, the terminal B, the terminal C,
Shall be sent to terminal D, and the address of each terminal shall be
It is set to 10H, 20H, 21H, and 22H, respectively ("H" represents a hexadecimal number).

In normal communication that is not broadcast,
As shown in FIG. 29, first, terminal A transmits to terminal B, then terminal A transmits to terminal C, and finally terminal A transmits to terminal D. That is, the same data is transmitted from terminal A three times. The source address is used as the source address, and the destination address is used as the destination address, which is added to the communication packet and transmitted. Then, each terminal on the receiving side fetches only the communication packet whose destination address matches the address of its own terminal.

On the other hand, in broadcast communication,
As shown in FIG. 30, the destination address is set to "FFH" which is a specific address number and is transmitted only once. And each terminal on the receiving side
If the address is "FFH", the packet is unconditionally fetched.

By the way, in the case of normal communication which is not broadcast, since it is one-to-one communication, a response can be returned from the receiving side to the transmitting side. That is, if the reception is normally completed, a response packet indicating that can be transmitted from the receiving side to the transmitting side. Then, the sending side (of normal communication that is not broadcast) can judge whether the communication packet sent by its own terminal has reached the other terminal normally, depending on whether this response packet is returned or not. If the response packet is not returned within a fixed time, some kind of recovery processing such as resending the packet can be performed.

On the other hand, in broadcast communication,
Since it is not one-to-one communication, there is no response packet. This is because, since the packets arrive at the receiving terminals at the same time, the response packets are also returned at the same time, and the response packets collide with each other and are destroyed. Therefore, in broadcast communication, response confirmation in an upper layer such as an application is generally used.

[0007]

In the conventional broadcast communication, it is assumed that the receiving side terminal returns a response from the upper layer to the transmitting side terminal, and the terminal which does not receive this response within a certain time period. Retransmits the data individually,
It is assumed that there is a response to each individual data retransmission, and the arrival rate of broadcast communication is X (O ≦ X ≦
1) If the number of terminals on the receiving side is Y, the total number of transmissions and responses for sending data to all terminals is “Z”.
1 "is as follows.

[0008]

By the way, in the case of wireless broadcast communication (for example, wireless LAN), the reachability X of the broadcast is lowered due to the surrounding radio wave environment. There is a problem that the total Z1 increases and the line efficiency decreases. The present invention has been made in consideration of such circumstances, and provides a broadcast communication system capable of suppressing a decrease in line efficiency with respect to a decrease in a broadcast arrival rate.

[0010]

SUMMARY OF THE INVENTION The present invention is a broadcast communication system configured to transmit and receive data contained in a packet for communication between one terminal and another terminal. Is provided with a transmitting means for repeatedly transmitting a packet containing the same data a plurality of times, and the receiving side terminal compares the data of the packet received a plurality of times with the receiving means for receiving the transmitted packet and duplicates them. The present invention provides a broadcast communication system characterized by including an identification unit that takes in one of the data as valid data and discards the other as invalid data.

The broadcast communication method of the present invention is a method of transmitting data from one transmitting terminal to a plurality of receiving terminals without designating the receiving terminals, as is conventionally known. In the conventional broadcast communication method, since the same data is transmitted only once, the number of retransmissions, that is, the number of retransmissions, increases with a decrease in the arrival rate to the receiving terminal. By continuously transmitting once, the increase in the number of retransmissions due to the decrease in the arrival rate to the receiving terminal is suppressed.

The packet for communication in the present invention means, for example, a group of communication data of a predetermined format as used in an asynchronous time division multiplexing system known in the art, and usually a flag and an address bit. , Control bits, data and check bits. Further, in order to identify the data of the packet, the control bit may include an identifier (for example, a sequence number).

According to the present invention, in the transmitting side terminal, the transmitting means repeatedly transmits the packet containing the same data a plurality of times, and in the receiving side terminal, the receiving means receives the transmitted packet and the identifying means , The data of the packets received a plurality of times are compared with each other, one of the overlapping data is taken in as valid data, and the other is discarded as invalid data.

The transmitting side terminal further comprises an adding means for adding an identifier (for example, a sequence number) corresponding to the data contained in the packet to the packet, and the identifying means of the receiving side terminal is the identifier added to the packet. An identifier detecting means for detecting valid data based on the above may be provided.
This facilitates the identification processing of the same data in the receiving side terminal. Further, the transmitting means of the transmitting side terminal may transmit each packet at predetermined time intervals.

Further, the transmitting means of the transmitting side terminal may be provided with a plurality of different transmitting antennas and an antenna switching means for transmitting each packet sequentially through different antennas.
The receiving means of the transmitting side terminal comprises a transmitting means for repeatedly transmitting a packet containing the same data a plurality of times at different frequencies, and the receiving means of the receiving side terminal receives a packet repeatedly transmitted at the above different frequencies. It may consist of means. The transmitting means of the transmitting side terminal may include a plurality of transmitting antennas having different directivities, and an antenna switching means for sequentially transmitting each packet via antennas having different directivities.

Further, according to the present invention, data to be transmitted is formed in a transmission side terminal in a broadcast communication system configured to transmit and receive data contained in a packet for communication between one terminal and another terminal. The present invention provides a transmission side terminal in a broadcast communication system, characterized by comprising a forming means and a transmitting means for accommodating the formed data in a packet and repeatedly transmitting the packet a plurality of times.

Further, according to the present invention, in a receiving side terminal in a broadcast communication system configured to transmit and receive data contained in a packet for communication between one terminal and another terminal, a packet transmitted by a transmitting side terminal And a receiving means for receiving a plurality of packets, comparing the data of the received packets with each other and taking one of the overlapping data as valid data and discarding the other as invalid data. The present invention provides a receiving side terminal in a broadcast communication system characterized by being provided.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the drawings. This does not limit the invention.

Embodiment 1 FIG. 1 is a block diagram showing a configuration of a transmission side terminal and a reception side terminal in Embodiment 1, a terminal 1 is an apparatus having a wireless communication (transmission / reception) function, and an arithmetic unit 2 is According to the contents recorded in the storage device 3, the transmission data is sent to the parallel-serial conversion device 5 using the primary storage device 4 as a work area, whereby the parallel data is converted into serial data, which is inserted into the communication packet and modulated. It is modulated by the device 6 and transmitted from the antenna 7. Further, the packet received from the antenna 7 is demodulated by the demodulator 9 and the received data contained in the packet is converted from serial data to parallel data by the serial / parallel converter 8 and transmitted to the arithmetic unit 2 to the storage unit 3. According to the recorded contents, the temporary storage device 4 is processed as a work area. The arithmetic unit 2 may be equipped with an input unit 10 and an output unit 11, and exchanges information with the outside as needed.

The above operation will be described with reference to a flow chart. In addition, for simplification of description, the number of times of transmission is described as the first transmission and the number of retransmissions, but the same can be said for the number of transmissions greater than that.

FIG. 2 is a flowchart showing the operation of the transmitting side in a system that does not use a sequence number (data identifier). First, the arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 to check the presence or absence of broadcast transmission data (step S1). If there is transmission data, the arithmetic unit 2 sends the transmission data prepared in the storage device 3 or the temporary storage device 4 to the parallel / serial conversion device 5, and the parallel / serial conversion device 5
Converts the parallel data sent from the arithmetic unit 2 into serial data, inserts it into a packet, converts it into a signal that can be transmitted by the modulator 6, and then performs the first transmission with the antenna 7 (step S2). . After that, the packet in which the same data is inserted is retransmitted (step S3). Then, the process returns to step S1 again, and the presence / absence of broadcast data to be transmitted next is checked.

FIG. 3 is a flowchart showing the operation on the receiving side in a system that does not use a sequence number (data identifier). The packet received by the antenna 7 is demodulated by the demodulator 9
The received signal is converted into a signal that can be handled by the terminal, and the serial / parallel converter 8 converts the serial data of the packet sent from the demodulator 9 into parallel data, which is passed to the arithmetic unit 2 and stored in the storage unit 3. By referring to the contents of the temporary storage device 4 according to the procedure, it is checked whether or not the received data is a broadcast reception data (step S11). If it is the received data, the arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 and checks whether the received data is the same as the received data of the broadcast received last time (step S12). ). If the contents are not the same, the arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 and processes them as valid broadcast data (step S13). If the data is the same, the arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 and discards it as invalid broadcast data (step S14). afterwards,
In step S11, the reception data of the next broadcast is awaited.

FIG. 4 is a flowchart showing the operation of the transmitting side in the system using the sequence number. FIG. 5 shows a format of a packet to be transmitted, in which a sequence number and data are included. The arithmetic unit 2 initializes the sequence number to "0" while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S21). The arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 and checks for the presence of broadcast transmission data (step S
22). If there is transmission data, the arithmetic unit 2 adds a sequence number to the transmission data prepared in the storage unit 3 or the temporary storage unit 4 and sends it to the parallel / serial conversion unit 5, and the parallel / serial conversion unit 5 sends it from the arithmetic unit 2. The parallel data thus received is converted into serial data, inserted into a packet, converted into a signal that can be transmitted by the modulator 6, and then the first transmission is performed from the antenna 7 (step S23). After that, the packet including the same data is retransmitted by the same procedure as the previous time (step S24). Then, the arithmetic unit 2 increments the sequence number by “1” while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S2
5) Then, the process returns to step S22 again to check the presence / absence of broadcast data to be transmitted next. The sequence number may be stored in the temporary storage device 4,
It may be stored in an internal register of the arithmetic unit 2.

FIG. 6 shows the operation of the receiving side of the system using the sequence number. The packet received by the antenna 7 is converted from the received signal by the demodulator 9 into a signal that can be handled by the terminal, and the serial / parallel converter 8 converts serial data contained in the packet sent from the demodulator 9 into parallel data. While referring to the contents of the temporary storage device 4 according to the procedure stored in the storage device 3 passed to the arithmetic unit 2, it is checked whether or not the received data is a broadcast reception data (step S31). If the received data, the arithmetic processing 2 follows the procedure stored in the storage device 3 and the temporary storage device 4
While referring to the contents of the above item, it is checked whether or not it is the same sequence number as the received data of the previously received broadcast (step S32). If they are not the same sequence number, the processing unit 2 processes them as valid broadcast data while referring to the contents of the temporary storage unit 4 according to the procedure described in the storage unit 3 (step S3).
3). If the sequence numbers are the same, the arithmetic unit 2 follows the procedure stored in the storage unit 3 and the temporary storage unit 4
While referring to the contents of the above item, it is processed as invalid broadcast data (step S34). After that, again in step S31, the reception data of the next broadcast is awaited. The sequence number may be stored in the temporary storage device 4 as in the transmitting side, or may be stored in the internal register of the arithmetic unit 2.

Second Embodiment Since the configuration of the terminal device in the second embodiment is the same as that shown in FIG. 1, the description thereof will be omitted and the operation will be described using a flowchart. In addition, for simplification of description, the number of transmissions is described as two times, that is, the first transmission and the retransmission, but the same can be said for more transmissions.

FIG. 7 is a flowchart showing the operation of the transmitting side in a system that does not use sequence numbers. The arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 and checks the presence or absence of broadcast transmission data (step S41). If there is transmission data, the arithmetic unit 2 sends the transmission data prepared in the storage unit 3 or the temporary storage unit 4 to the parallel / serial conversion unit 5, and the parallel / serial conversion unit 5 sends the parallel data sent from the arithmetic unit 2. Is converted into serial data, inserted into a packet, converted into a signal that can be transmitted by the modulator 6, and then the antenna 7 performs the first transmission (step S42). Then, after a certain time has passed (step S43), the same data is retransmitted by the same procedure as the previous time (step S4).
4). Then, the process returns to step S41 again, and the presence / absence of broadcast data to be transmitted next is checked. The operation on the receiving side is the same as that of the flowchart shown in FIG.

FIG. 8 is a flowchart showing the operation of the transmitting side in the system using the sequence number. The format of the packet to be transmitted is as shown in FIG. 5, and includes a sequence number and data. The arithmetic unit 2 initializes the sequence number to "0" while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S51). The computing device 2 refers to the contents of the temporary storage device 4 in accordance with the procedure stored in the storage device 3 and checks the presence or absence of broadcast transmission data (step S52). If there is transmission data, arithmetic unit 2
Adds a sequence number to the transmission data prepared in the storage device 3 or the temporary storage device 4 and sends it to the parallel-serial conversion device 5, and the parallel-serial conversion device 5 converts the parallel data sent from the arithmetic unit 2 into serial data. Convert it and insert it in the packet,
After the signal is converted into a signal that can be transmitted by the modulator 6, the antenna 7 performs the first transmission (step S53). Then, after a certain time has passed (step S54), the same data is retransmitted by the same procedure as the previous time (step S5).
5). Then, the arithmetic unit 2 increments the sequence number by “1” while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S56), and then returns to step S52 again to broadcast for the next transmission.・ Check for the existence of data. The sequence number may be stored in the temporary storage device 4 or may be stored in the internal register of the arithmetic unit 2. The operation on the receiving side in the system using the sequence number is as described in the first embodiment.
Since it has already been described with reference to FIG. 6 in FIG.

Third Embodiment FIG. 9 is a block diagram showing the configuration of the transmitting side and receiving side terminals in the third embodiment. The terminal 1A is a device having a wireless communication function, and the arithmetic unit 2 sends the transmission data to the parallel / serial conversion device 5 in accordance with the contents recorded in the storage device 3, using the temporary storage device 4 as a work area. As a result, the parallel data is converted into serial data, inserted into the packet, modulated by the modulator 6, and transmitted by the antenna switching device 12 from the antenna 7A or the antenna 7B. The packet is transmitted to the antenna 7 on the receiving side.
The antenna switching device 1 is received by A and the antenna 7B.
One of the received data switched by 2 is demodulated by the demodulator 9 and then converted from serial data to parallel data by the serial-parallel converter 8 and transmitted to the arithmetic unit 2 and recorded in the storage unit 3. According to the contents, the temporary storage device 4 is processed as a work area. The arithmetic unit 2 may be equipped with an input unit 10 and an output unit 11, and exchanges information with the outside as needed. Next, the operation of the third embodiment will be described using a flowchart. In order to simplify the explanation, the number of times of antenna switching is one, that is, one transmission by the antenna A and one transmission by the antenna B.
Although it has been described that the transmission is performed once, the same applies to the case where the transmission is performed more times.

FIG. 10 is a flowchart showing the operation of the transmitting side in a system that does not use sequence numbers. The arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 and checks the presence or absence of broadcast transmission data (step S61). If there is transmission data, the arithmetic unit 2 instructs the antenna switching unit 12 while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 to switch the antenna to the antenna 7A (step S62). Then, the arithmetic unit 2 sends the transmission data prepared in the storage unit 23 or the temporary storage unit 4 to the parallel / serial conversion unit 5, and the parallel / serial conversion unit 5 converts the parallel data sent from the arithmetic unit 2 into serial data. Then, after being converted into a signal that can be transmitted by the modulator 6, the first transmission is performed by the antenna 7A (step S63). After that, the antenna is switched to the antenna 7B in the same procedure as last time (step S64), and the same data is retransmitted in the same procedure as last time (step S65). Then, the process returns to step S61 again, and the presence or absence of the broadcast data to be transmitted next is checked. The operation on the receiving side is the same as the operation shown in FIG.

FIG. 11 is a flowchart showing the operation of the transmitting side in the system using the sequence number. The format of the packet to be transmitted is as shown in FIG. 5, and the sequence number is included in this. The arithmetic unit 2 initializes the sequence number to "0" while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S71). The computing device 2 refers to the contents of the temporary storage device 4 according to the procedure stored in the storage device 3,
The presence / absence of broadcast transmission data is checked (step S72). If there is transmission data, the arithmetic unit 2 follows the procedure stored in the storage unit 3 and the temporary storage unit 4
The antenna switching device 12 is instructed to switch the antenna to the antenna 7A while referring to the contents of the above (step S
73). Then, the arithmetic unit 2 adds a sequence number to the transmission data prepared in the storage unit 3 or the temporary storage unit 4 and sends it to the parallel / serial conversion unit 5, and the parallel / serial conversion unit 5 sends the parallel data sent from the arithmetic unit 2. Is converted into serial data and converted into a signal that can be transmitted by the modulator 6,
The first transmission is performed by the antenna 7A (step S7).
4). After that, follow the same procedure as the previous time and set the antenna 7
The mode is switched to B (step S75), and the same data is retransmitted by the same procedure as the previous time (step S76). Then, the arithmetic unit 2 increments the sequence number by “1” while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S77), and then returns to (step S72) again, and next. Broadcast to send
Check for data. The sequence number may be stored in the temporary storage device 4 or may be stored in the internal register of the arithmetic unit 2. The operation on the receiving side in the system using the sequence number is the same as that already described with reference to FIG.

Fourth Embodiment FIG. 12 is a block diagram showing the configuration of the fourth embodiment. The terminal 1B is a device having a wireless communication function, and the arithmetic device 2 is in accordance with the contents recorded in the storage device 3. , The transmission data is sent to the parallel / serial conversion device 5 using the temporary storage device 4 as a work area, and the transmission data converted from the parallel data to the serial data by the modulation device 6A for frequency A or the modulation device 6B for frequency B is modulated. Then, the modulator switching device 13 transmits the signal from the frequency A modulator 6A or the frequency B modulator 6B from the antenna 7. Further, the received data is received by the antenna 7, demodulated by the frequency A demodulation device 9A or the frequency B demodulation device 9B, and thereafter converted from serial data to parallel data by the serial-parallel converter 8 and transmitted to the arithmetic unit 2. According to the contents recorded and stored in the storage device 3,
The temporary storage device 4 is processed as a work area. The arithmetic unit 2 may be equipped with an input unit 10 and an output unit 11, and exchanges information with the outside as needed. The above operation will be described with a flowchart. For the sake of simplicity, the number of transmissions at each frequency is one, that is, one transmission at frequency A and one transmission at frequency B, but the same method can be used for more transmissions. It can be carried out.

FIG. 13 is a flow chart showing the operation of the transmitting side in a system that does not use sequence numbers. The arithmetic unit 2 refers to the contents of the temporary storage unit 4 in accordance with the procedure stored in the storage unit 3 and checks whether there is broadcast transmission data (step S81). If there is transmission data, the arithmetic unit 2 instructs the modulator switching unit 13 while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3, and sets the modulation unit to the frequency A modulation unit 6A. (Step S82). Then, the arithmetic unit 2 sends the transmission data prepared in the storage unit 3 or the temporary storage unit to the parallel / serial conversion unit 5, and the parallel / serial conversion unit 5 converts the parallel data sent from the arithmetic unit 2 into serial data. , The signal is converted into a signal that can be transmitted by the frequency A modulation device 6A, and then the antenna 7 performs the first transmission (step S83). After that, the modulator is switched to the frequency B modulator 6B in the same procedure (step S
84), and the same data is retransmitted in the same procedure as the previous time (step S85). Then, the process returns to step S81 again, and the presence / absence of broadcast data to be transmitted next is checked.

FIG. 14 is a flowchart showing the operation on the receiving side in a system that does not use sequence numbers. If the frequency of the data received by the antenna 7 is A, the demodulator 9A for the frequency A converts the received signal into a signal that can be handled by the terminal. If the frequency B is the demodulator 9B for frequency B, the received signal is also converted from the received signal to the terminal. Is converted into a signal that can be handled. Then, the serial-parallel converter 8 converts the serial data sent from the frequency A demodulator 9A or the frequency B demodulator 9B into parallel data and transfers it to the arithmetic unit 2 according to the procedure stored in the storage unit 3. While referring to the contents of the temporary storage device 4, it is checked whether or not the data is broadcast reception data (step S86). If the received data, the arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 and checks whether the contents are the same as the received data of the broadcast received last time (step S87). ). If the contents are not the same, the arithmetic unit 2 processes the contents as temporary broadcast data while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S88). If the data is the same, the arithmetic unit 2 processes it as invalid broadcast data while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S89). When these processes are completed, the process waits for the next broadcast reception data again in step S86.

FIG. 15 is a flow chart showing the operation of the transmitting side in the system using the sequence number. The format of the data to be transmitted is as shown in FIG. 5, in which the sequence number is included. The arithmetic unit 2 initializes the sequence number to "0" while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S91). The arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 and checks the presence or absence of broadcast transmission data (step S92). If there is transmission data, the arithmetic unit 2 instructs the modulator switching unit 13 while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3,
The modulator is switched to the frequency A modulator 6 (step S93). Then, the arithmetic unit 2 adds a sequence number to the transmission data prepared in the storage unit 3 or the temporary storage unit 4 and sends it to the parallel / serial conversion unit 5, and the parallel / serial conversion unit 5
Converts the parallel data sent from the arithmetic unit 2 into serial data and converts it into a signal that can be transmitted by the frequency A modulator 6A, and then performs the first transmission by the antenna 7 (step S94). Then, the frequency B modulator 6B is switched in the same procedure (step S95), and the same data is retransmitted (step S96). Then, the computing device 2 follows the procedure stored in the storage device 3 and temporarily stores the data in the temporary storage device 4.
The sequence number is incremented by "1" (step S97) while referring again to the contents of step S92, and the process returns to step S92 to check the presence / absence of broadcast data to be transmitted next. The sequence number may be stored in the temporary storage device 4 or may be stored in the internal register of the arithmetic device 4.

FIG. 16 is a flowchart showing the operation of the receiving side in the system using the sequence number. If the frequency of the data received by the antenna 7 is A, the demodulator 9A for frequency A converts the received signal into a signal that can be handled by the terminal, and if the frequency is B, the demodulator 9B for frequency B also converts the received signal from the received signal to the terminal. Is converted into a signal that can be handled. Then, the serial-to-parallel converter 8 converts the serial data sent from the frequency A demodulator 9A or the frequency B demodulator 9B into parallel data, passes the parallel data to the arithmetic unit 2, and stores it in the procedure stored in the storage unit 3. Therefore, referring to the contents of the temporary storage device 4, it is checked whether or not the received data is a broadcast reception data (step S98).
If it is received data, the arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 and checks whether it has the same sequence number as the received data of the broadcast received last time (step S
99). If they are not the same sequence number, the arithmetic unit 2 processes them as valid broadcast data while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S100). If the sequence numbers are the same, the arithmetic unit 2 processes as invalid broadcast data while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S101). When the above processing is completed, the process waits for the next broadcast reception data in step S98. The sequence number may be stored in the temporary storage device 4 as in the transmitting side, or may be stored in the internal register of the arithmetic unit 2.

Fifth Embodiment FIG. 17 is a block diagram showing the configuration of the transmitting side and receiving side terminals in the fifth embodiment. The terminal 1C is a device having a wireless communication function, and the arithmetic device 2 is a storage device 3
In accordance with the contents recorded in, the transmission data is sent to the parallel / serial conversion device 5 using the temporary storage device 4 as a work area, whereby the transmission data converted from parallel data to serial data is inserted into a packet and modulated by the modulation device 6. Then, it is transmitted by the antenna switching device 12A via the antenna 7a, the antenna 7b, the antenna 7c, or the antenna 7d. The received packet is received by the antenna 7a, the antenna 7b, the antenna 7c, and the antenna 7d,
The reception packet from any one of the antennas switched by the antenna switching device 12A is demodulated by the demodulation device 9, and then the data of the packet is converted from serial data to parallel data by the serial / parallel conversion device 8 and then sent to the arithmetic device 2. According to the contents transmitted and recorded in the storage device 3, the temporary storage device 4 is processed as a work area. The arithmetic unit 2 may be equipped with an input unit 10 and an output unit 11, and exchanges information with the outside as needed.

Next, FIG. 18 shows an example of arrangement of antennas. It is assumed that the terminal 1c is located in the center of the space F, and the antenna 7a supports the area A, the antenna 7b supports the area B, the antenna 7c supports the area C, and the antenna 7d supports the area D. There is.
Here, assuming that the transmitting side has the configuration of FIG. 17, the operation of the transmitting side will be described using the flowchart of FIG. For simplification of explanation, each antenna switching circuit 12A has one
Times, that is, one transmission by the antenna 7a and one transmission by the antenna 7b
It is described that the transmission is performed once by the antenna, the transmission by the antenna 7c is performed once, and the transmission by the antenna 7d is performed once.

FIG. 19 shows a transmission operation in a system that does not use sequence numbers. The computing device 2 refers to the contents of the temporary storage device 4 according to the procedure stored in the storage device 3 and checks whether or not there is broadcast transmission data (step S111). If there is transmission data, the arithmetic unit 2 refers to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3, and the antenna switching unit 12A
To switch the antenna to the antenna 7a (step S112). Then, the arithmetic unit 2 sends the transmission data prepared in the storage unit 3 or the temporary storage unit 4 to the parallel / serial conversion unit 5, and the parallel / serial conversion unit 5 converts the parallel data sent from the arithmetic unit 2 into serial data. First, the signal is inserted into a packet by the modulator 7 and converted into a signal that can be transmitted by the modulator 6, and then the first transmission is performed by the antenna 7a (step S
113). After that, the antenna is switched to the antenna 7b in the same procedure in step S112 (step S114), and the packet including the same data is retransmitted in the same procedure as step S113 (step S115). Next, step S1
The antenna is switched to the antenna 7c in the same procedure as in step 12 (step S116), and the packet containing the same data is retransmitted in the same procedure as in step S113 (step S11).
7). Next, in the same procedure as step S112, the antenna 7
The packet is switched to d (step 118), and the packet including the same data is retransmitted by the same procedure as step S113 (step S119). Then, the process returns to step S111 again, and the presence / absence of broadcast data to be transmitted next is checked. On the receiving side, the antennas 7a, 7b,
The packet is received by 7c or 7d, and the received packet is converted by the demodulation device 9. Since the operation thereafter is the same as that of FIG. 3 of the first embodiment, the description thereof will be omitted.

FIG. 20 is a flow chart showing the operation of the transmitting side in the system using the sequence number. The format of the packet to be transmitted is as shown in FIG. 5, in which the sequence number and the transmission data are included. The arithmetic unit 2 initializes the sequence number to "0" while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S120). The arithmetic unit 2 checks the presence / absence of broadcast transmission data while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S121). If there is transmission data, the arithmetic unit 2 instructs the antenna switching unit 12A while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3, and switches the antenna to the antenna 7a (step S122). . Then, the arithmetic unit 2 sends the transmission data and the sequence number prepared in the storage unit 3 or the temporary storage unit 4 to the parallel / serial conversion unit 5. The parallel-serial converter 5 converts the parallel data sent from the arithmetic unit 2 into serial data, inserts it into a packet, converts it into a signal that can be transmitted by the modulator 6, and then performs the first transmission by the antenna 7a. Perform (step S123). After that, step S1
The antenna 7a is switched to the antenna 7b in the same procedure as in step 22 (step S124), and the packet containing the same data is retransmitted in the same procedure as in step S123 (step S1).
25). Next, the antenna 7b is switched to the antenna 7c in the same procedure as step S122 (step S126),
The same data is retransmitted in the same procedure as in step S123 (step S127). Next, the antenna 7c is switched to the antenna 7d in the same procedure as in step S122 (step S128), and the packet containing the same data is retransmitted in the same procedure as in step S123 (step S129). Then, the arithmetic unit 2 increments the sequence number by “1” while referring to the contents of the temporary storage unit 4 according to the procedure stored in the storage unit 3 (step S130), and then returns to step S121 again to transmit next. Check for broadcast data. The sequence number may be stored in the temporary storage device 4 or the calculation device 2
It may be stored in the internal register of.

On the receiving side, the antenna 7
the packet is received by a, 7b, 7c or 7d,
The received packet is converted by the demodulator 9. Since the operation thereafter is the same as that of FIG. 3 of the first embodiment, the description thereof will be omitted.

The sum of the number of transmissions and the number of responses in each embodiment
Total (1) in order to send all the data of a plurality of terminals in Example 1 and 2, a total of "Z2" of the response times and the transmission times is as follows.

However, the arrival rate of the broadcast is X, the number of terminals on the receiving side is Y, and the number of times of transmitting the same data is N times.

(2) Cases of Embodiments 3 and 4 In order to send data to all of a plurality of terminals, the total "Z3" of the number of transmissions and the number of responses is as follows. However, the arrival rate of the broadcast by one antenna or the frequency of one side is X1, the arrival rate of the broadcast by the other antenna or the frequency of one side is X2,
The number of terminals on the receiving side is Y, and the number of times of transmitting the same data is N. Next, in order to explain the effect of each embodiment,

The characteristics of the equations (1), (2) and (3) will be described graphically. First, FIG. 21 shows a comparative example, that is, the case of Z1 shown in Expression (1), and shows that the total communication count Z1 linearly increases as the broadcast communication reachability deteriorates. FIG. 22 is a graph of Z2 shown in Expression (2), in the case where the number of retransmissions is two. Although there is not much difference between the broadcast communication reach rates near “0” and around “1” as compared with the case of Z1, the total number of communications is slightly decreased during that time.

FIG. 23 shows Z2 when the number of retransmissions is four.
Therefore, there is not much difference between when the broadcast communication reachability is near “0” and when it is around “1” as compared with the case of Z1, but the total number of communications during that time is further reduced as compared with the case of FIG. Figure 2
4 is Z2 when the number of retransmissions is eight, and Z1 when the broadcast communication reach rate is near “0” and near “1”.
Although there is not much difference from the case of, the total number of communications during that time is further reduced as compared with the case of FIG. If the broadcast communication arrival rate is about 0.3 or more, the total number of times of communication is the same as that in the case of almost “1”. FIG. 25 is a graph showing Z2 when the number of retransmissions is 16.

As described above, the first and second embodiments have the following effects. (1) The total number of communications is effectively improved except when the broadcast communication arrival rate is near "0" and "1". (2) As the number of retransmissions is increased, the total number of communications is improved even near the broadcast communication arrival rate of “0”. Next, in order to show the effects of Examples 3 and 4, the broadcast non-arrival rate when the antenna and the frequency are not switched,
The graph shows the difference in the broadcast non-arrival ratio when switching the antenna and frequency.

First, FIG. 26 shows the difference expressed by the following equation. However, the difference of Expression (4) in which the arrival rate of the broadcast by one antenna or the frequency is X1 and the arrival rate of the broadcast by the other antenna or the frequency is X2 is always positive, and Examples 3 and 4 are compared with the comparative example. It shows that there is an effect.

Next, FIG. 27 shows the difference in non-attainment rate expressed by the following equation. However, the arrival rate of broadcast by one antenna or frequency is X1, and the arrival rate of broadcast by the other antenna or frequency is X2 min (X1, X2) is the smaller value of X1 and X2. The difference is always positive, indicating that it is about twice that in FIG.

Next, FIG. 28 shows the difference in non-arrival rate expressed by the following equation. However, the reachability of the broadcast by one antenna or frequency is X1, and the reachability of the broadcast by the other antenna or frequency is X2 max (X1, X2) is the larger value of X1 and X2. The difference is always negative, It can be seen that the absolute value is about ⅕ times the difference in FIG.

From the above, Examples 3 and 4 have the following effects. (1) The non-arrival rate is smaller than the non-arrival rate of one antenna having the average reachability of two antennas. (2) The non-arrival rate is considerably larger than the non-arrival rate of the antenna with the lower reach rate of the two antennas, and the antenna with the higher reach rate of the two antennas is used. It is a little smaller than the non-arrival rate when used. Since the absolute value of the latter is smaller than the absolute value of the former, when the reachability of each of the two antennas is unknown, the method according to this embodiment is used rather than using either one of the antennas.
Probably low non-attainment rate.

The effects of the fifth embodiment are as follows.
A directional antenna has a longer reach of radio waves with the same power than an omnidirectional antenna, and conversely, transmission and reception can be performed with less power with the same reach. Therefore, (1) Longer reach can be obtained with the same power. (2) With the same reach distance, it is possible to transmit and receive with less power. (3) With the same power and the same reach, communication can be performed with a smaller error rate. That is, the number of retransmissions is reduced, and the total communication time can be shortened.

[0052]

According to the present invention, the number of communications required for the receiving side terminal to reliably receive data is smaller than the conventional one except when the broadcast communication arrival rate is around 0 or 1, and the repeated transmission is performed. As the number of times of broadcast communication increases, the broadcast communication arrival rate becomes smaller than in the conventional case even when the arrival rate is close to zero. Further, when the communication means of the transmission side terminal transmits each packet sequentially by a plurality of different transmission antennas or frequencies, the broadcast communication arrival rate is improved on average. Furthermore, when each packet is sequentially transmitted via a plurality of antennas having different directivities, communication between terminals at a long distance can be performed with a small amount of power.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a configuration of a first embodiment.

FIG. 2 is a flowchart showing the operation of the first embodiment.

FIG. 3 is a flowchart showing the operation of the first embodiment.

FIG. 4 is a flowchart showing the operation of the first embodiment.

FIG. 5 is an explanatory diagram showing a format of a communication packet according to the first embodiment.

FIG. 6 is a flowchart showing the operation of the first embodiment.

FIG. 7 is a flowchart showing the operation of the second embodiment.

FIG. 8 is a flowchart showing the operation of the second embodiment.

FIG. 9 is a block diagram showing a configuration of a third embodiment.

FIG. 10 is a flowchart showing the operation of the third embodiment.

FIG. 11 is a flowchart showing the operation of the third embodiment.

FIG. 12 is a block diagram showing a configuration of a fourth embodiment.

FIG. 13 is a flowchart showing the operation of the fourth embodiment.

FIG. 14 is a flowchart showing the operation of the fourth embodiment.

FIG. 15 is a flowchart showing the operation of the fourth embodiment.

FIG. 16 is a flowchart showing the operation of the fourth embodiment.

FIG. 17 is a block diagram showing the configuration of the fifth embodiment.

FIG. 18 is a layout view showing the layout of the fifth embodiment.

FIG. 19 is a flowchart showing the operation of the fifth embodiment.

FIG. 20 is a flowchart showing the operation of the fifth embodiment.

FIG. 21 is a graph showing the total number of communications in a comparative example.

FIG. 22 is a graph showing an example of the total number of communications in the first and second embodiments.

FIG. 23 is a graph showing an example of the total number of times of communication in the first and second embodiments.

FIG. 24 is a graph showing an example of the total number of times of communication in the first and second embodiments.

FIG. 25 is a graph showing an example of the total number of communications in the first and second embodiments.

FIG. 26 is a graph showing a difference in broadcast non-arrival rate between Example 3 and Example 4 and a comparative example.

FIG. 27 is a graph showing a difference in broadcast non-arrival rate between Example 3 and Example 4 and a comparative example.

FIG. 28 is a graph showing a difference in broadcast non-arrival rate between Example 3 and Example 4 and a comparative example.

FIG. 29 is an explanatory diagram showing a conventional non-broadcast communication method.

FIG. 30 is an explanatory diagram showing a conventional broadcast communication system.

[Explanation of symbols]

 1 Terminal 2 Arithmetic Device 3 Storage Device 4 Temporary Storage Device 5 Parallel-Serial Conversion Device 6 Modulator 7 Antenna 8 Serial-Parallel Conversion Device 9 Demodulation Device 10 Input Device 11 Output Device

Claims (4)

[Claims] 1. Data stored in a packet for communication is 1
In a broadcast communication method configured to send and receive between one terminal and another terminal, the sending terminal is equipped with sending means for repeatedly sending a packet containing the same data multiple times, and the receiving terminal sends A packet receiving unit that receives multiple packets, and an identifying unit that compares the data of the packets received a plurality of times with each other and takes one of the overlapping data as valid data and discards the other as invalid data. Characteristic broadcast communication method. 2. The transmitting side terminal further comprises an adding means for adding an identifier corresponding to the data contained in the packet to the packet, and the identifying means of the receiving side terminal is effective based on the identifier added to the packet. The broadcast communication system according to claim 1, further comprising an identifier detection unit that detects data. 3. The data contained in a packet for communication,
In a transmitting side terminal in a broadcast communication system configured to transmit and receive between one terminal and another terminal, forming means for forming data to be transmitted and accommodating the formed data in a packet and transmitting repeatedly. A transmitting side terminal in a broadcast communication system, comprising: 4. The data contained in a packet for communication,
In a receiving side terminal in a broadcast communication system configured to transmit and receive between one terminal and another terminal, a receiving means for receiving a packet transmitted by a transmitting side terminal, and a receiving packet for receiving a plurality of packets A receiving side terminal in a broadcast communication system, comprising: identification means for comparing data with each other and taking in one of duplicate data as valid data and discarding the other as invalid data.