JP2000278727A - Communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow many unspecified people to simply exchange data. SOLUTION: A transmission ID of a received message requesting a reply is sued for a transmission ID of a reply message without any modification (S24). Then a random number is generated and the decided random number is used for a reception ID (S25, S26), a check sum is calculated and a message is assembled (S14, S15). When receiving no message from other mobile communication unit, the reply message is transmitted (S22). When receiving data, a random number is generated (S20), a timer is preset according to the random number and the mobile communication unit awaits its transmission by a random time (S21). When the timer expires, the communication unit tries transmission again. A communication unit that is a destination of the reply message recognizes the message as to whether or not the message is addressed to itself on the basis of a communication ID of the reply message.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication apparatus for mutually transmitting and receiving data by radio signals.

[0002]

2. Description of the Related Art Data communication transmits data in a one-to-one or one-to-many (multicast, broadcast) manner. In data broadcasting, data is transmitted on a one-to-many basis. However, a data transmission method of exchanging data between many-to-many, that is, unspecified large numbers has not been widespread.

By the way, with the development of information processing technology and communication technology, general individuals are receiving data and interacting with each other. For example, as services on the Internet, an information browsing service (web server), a mail distribution service (mail server), a news distribution service, and the like can be enjoyed. As communication using such data has become widespread, it has been demanded that data be easily exchanged between unspecified large numbers. In particular, it is desired that a person who receives data (message) transmitted to an unspecified number of persons can easily reply to the sender.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above circumstances, and has as its object to provide a communication device that can easily reply to data addressed to an unspecified number of persons.

[0005]

According to the present invention, in order to achieve the above object, a communication device for transmitting / receiving a message by a radio signal transmits a means for generating a random number and an identifier comprising the random number. Means for incorporation into the target message, and when transmitting a reply message to the message received from the other party's transmission device, in addition to the identifier consisting of the random number, it is generated by the other party's transmission device and incorporated into the received message. Means for incorporating an identifier consisting of the random number into the reply message, means for transmitting a message incorporating the identifier, means for receiving the message, and when the received message contains an identifier consisting of a random number generated by itself. And means for determining a reply message addressed to itself.

In this configuration, the random number in the communication device of the origin included in the message is used as if it were a unique identifier of the communication device, and when the message is returned, the random number is included as a reply destination, thereby making the reply destination Reply message can be received effectively. When communication is performed between a limited number within a limited range, a message can be easily replied by using a random number as an identifier. With this configuration, identification can be performed with an identifier having a smaller number of bits than when a physical identification number is assigned to each device. The number of bits of the random number needs to correspond to the number of communication devices that transmit and receive at the same time, but this number is limited by the range of radio, obstacles, etc.
It is not necessary to increase the number of bits even if the number of shipped devices increases. In the case of a physical identifier, it is necessary to allocate a considerable bit length for the identifier with a margin in advance in consideration of the number of shipments, and this also puts pressure on the transmission band. It is not necessary to increase the number of bits even if the number of devices increases.

In this configuration, a message having an unspecified destination (a message other than a reply message or a message for a specific person) can include an identifier having a special value indicating that the destination is unspecified. . In this way, the receiving communication device can reliably receive a message (broadcast message) of an unspecified destination based on the special identifier.

[0008] When a message is exchanged between communication devices sharing a password, the password may be included in the identifier.

[0009] The random number may be generated based on profile information stored in the communication device main body. The profile information may include at least one of a user's date of birth, gender identification, and contact information.

[0010] Further, means for storing a plurality of random numbers generated for the identifier in the past may be provided, and whether or not the message is addressed to itself may be determined based on the plurality of stored random numbers. By doing so, it is possible to cope with the case where the random numbers are updated.

The message may be transmitted at a timing determined by a random number so as to avoid collision of the message between the communication devices.

Although the number of bits of the identifier becomes longer, when a physical device-specific identifier is allocated and a reply is made to the received message, the device identifier included in the received message is included in the reply message. It may be. The destination communication device of the reply message determines whether or not its own physical identifier is included in the reply message, and can recognize whether or not the reply message is addressed to itself based on the result of this determination.

[0013] In a communication device for exchanging messages in a wired network (for example, a local area network), it is needless to say that a message can be returned in a similar configuration by using a random number as an identifier. Further, when a wireless communication device and a communication device in a wired network exchange messages, the message can be exchanged using at least the identifier of the wireless communication device as a random number. The identifier of the communication device in the wired network may be unique to the device or may be a random number. A gateway is provided for exchanging messages between a wireless communication device and a communication device in a wired network.

[0014]

Embodiments of the present invention will be described below. The portable communication device of this embodiment operates in automatic transmission of a message, reception of a message, reply to the received message, and other modes. A message is a data unit exchanged between portable communication devices, and will be described later in detail.

In the automatic message transmission, a message is broadcast to a similar portable communication device, and the same message is transmitted at a predetermined repetition period, for example, every 10 seconds. Repeated transmission allows the message to be sent to many people. It is also possible to attach a password to the message so that only devices for which the password is set receive the message.

The reply to the message is a process of transmitting a reply message to the device that transmitted the message, and this process is performed once or a predetermined number of times. Reply messages should only be accepted at the reply destination. Such acceptance and selection of the message is performed using the communication ID included in the message. This point will be described later in detail.

Hereinafter, embodiments will be described in detail.

FIG. 1 shows the appearance of a portable communication device 1 of this embodiment, and FIG. 2 shows the internal configuration. FIG.
, The portable communication device 1 includes a circuit portion inside, and a liquid crystal display device 2, a power button 3, a key group 4,
The light emitting diode 5 is provided. Liquid crystal display device 2
Indicates input from a key, received data, stored data, transmitted data, and the like. The light emitting diode 5 performs a light emitting display in response to data reception. Although not shown, a buzzer is provided to generate a sound when a message is received. A vibrator may be provided to cause vibration when a message is received. The power button 3 is for controlling power on / off.

The key group 4 includes a feed / return button 4a, a decision button 4b, a scroll button 4c, a message button 4d, a symbol / function move button 4e, and a symbol button (function button).

Next, the internal configuration of the portable communication device 1 will be described. 2, parts corresponding to those in FIG. 1 are denoted by corresponding reference numerals. Note that the configuration in FIG. 2 is a schematic configuration, and it is needless to say that various modifications can be made by those skilled in the art.

In FIG. 2, the operation control unit 11, the storage unit 1
2, a transmission / reception unit 13, an input unit 14, a liquid crystal display device 2, a light emitting diode 5, and a speaker 15 are connected to a bus 16. The transmission / reception unit 13 and the input / output unit 14 are connected to the bus 16 via interfaces 13a and 14a, respectively. The liquid crystal display device 2 is driven by the drive unit 2a, and the speaker 15 and the light emitting diode 5 are driven by the drive unit 5a. Reference numeral 11a denotes a random number generation device, which is realized as a random number generation subroutine in this embodiment.
When generating a random number, a random number generation subroutine call is executed.

The transmission / reception unit 13 transmits a signal obtained by modulating a carrier of a weak radio wave with data to be transmitted to an external free space, and obtains data by demodulating the weak radio wave similarly transmitted. As a modulation method, any modulation method such as amplitude modulation, frequency modulation (FM), phase modulation (PSK), quadrature amplitude modulation (QAM), and code modulation can be adopted.

Of course, the carrier need not be a weak radio wave. In short, any radio wave that enables transmission and reception within a predetermined limited range may be used. The transmission / reception range is several meters to
It can be several tens of meters, or several meters to several hundred meters. Any device that can transmit and receive wirelessly, such as infrared rays instead of radio waves, can be used.

The storage unit 12 stores a control program and data. In this embodiment, as will be described later, data is exchanged in data units called messages (FIG. 4). In a message bank area (hereinafter simply referred to as a message bank) of the storage unit 12, the own message and a received message from another communication device (including a reply message) are stored.

FIG. 3 shows two portable communication devices 1A and 1B.
Shows how they communicate. The portable communication devices 1A and 1B
Data transmission / reception is performed using a weak radio wave (a radio wave having a transmission / reception range of several m to several tens m or several m to several hundred m). For example, a range of 20 m is a transmission / reception range. The portable communication devices 1A and 1B transmit messages at specific timings, for example, at intervals of 10 seconds (fixed time intervals of several seconds, of course, may be longer than several seconds). Upon receiving a message from another portable communication device, the portable communication devices 1A and 1B postpone their transmission. The extent of the postponement is determined randomly. The transmission delay period is determined by a random number output from the random number generator 11a. By doing so, it is possible to suppress transmission and reception collisions. When a collision occurs,
Only valid portions may be used, or all data may be discarded.

When performing collision avoidance control,
Only the communication ID (see FIG. 4) and predetermined flag data may be transmitted, and when the timing to avoid collision is determined, all data of the message may be transmitted.

In FIG. 3, two portable communication devices 1
A and 1B automatically transmit their own messages and receive messages from other communication devices. When another portable communication device 1C moves, as indicated by an arrow, the portable communication devices 1A, 1B, and 1C exchange messages with each other. If a portable communication device having a similar function is provided, an unspecified number of persons can exchange messages with each other.

FIG. 4 shows an example of the format of a message transmitted / received by the portable communication device 1. In this figure, the message 20 has character number data (1 byte),
It has a communication ID (4 bytes), profile data (24 bytes), a text body (36 bytes), and a checksum. SOT is the start code of the text, EO
T is the end code of the text. A predetermined preamble (not shown) is included before SOT. The communication ID is composed of a transmission ID (2 bytes) and a reception ID (2 bytes). The profile is an area representing a user attribute (profile), and includes a predetermined attribute (name,
Gender, birthday, tagline, hobby, height, contact information, password, etc.). Of course, the attribute item may be empty. The text body is for displaying a text message to be transmitted, and has a variable length. The number of bytes transferred is displayed in the character count data. The profile and the text body are input by operating the key group 4.

Note that some or all of the profile data may be omitted depending on the type of the message.

Each byte of the message is serialized,
A start bit, a parity bit, and a stop bit are added (total of 11 bits) and modulated. The modulation of the data bits used the so-called 33-66 modulation.

Here, the communication ID of the message will be described. The communication ID is the same as the 2-byte transmission ID.
It consists of a byte reception ID. Transmission ID and reception ID
Are assigned as follows according to the type of the message.

Normal Message A normal message is a message that is not a password message or a reply message. This includes a self-message that is repeatedly transmitted and a self-message that is transmitted one or more times. A random number (2 bytes) is used as the transmission ID (see steps S11 and S12 in FIG. 5). The reception ID is assumed to be zero (all zero bit string). Similarly, a random number is used as the password message transmission ID. The password itself is used as the reception ID. As the return message transmission ID, the transmission ID of the received original message is used as it is, and a random number held by its own device is used as the reception ID.

The random number is all zero or the password ID
Is very small. Therefore, the communication device receiving the message performs the following determination on the message.

When the received ID of the received message is all zero, it is determined that the received message is a normal transmission message (a message that is not a reply message or a password message). If the received ID of the received message is the same as the password held by itself, it is determined that the message is a password message addressed to the communication device. If the reception ID or transmission ID of the received message is the same as the random number held by itself, it is determined that the message is a reply message addressed to the communication device. The transmission ID of a reply message transmitted from the other party based on the message that the user first started to communicate with matches the own random number (current or past random number). Based on the message that the other party has started to communicate with first, it sends its own reply message, and if the other party sends another reply message, the reception ID of the reply message is its own random number (current or past random number) Matches.

In this embodiment, if the message is a normal message, a password message addressed to the self, and a reply message addressed to the self, the message is processed as valid, and if not, the message is discarded.

Next, the transmission / reception operation will be described.

First, the automatic transmission operation of the own message will be described. FIG. 5 shows an automatic transmission operation of its own message. In this figure, first, a random number generation subroutine (random number generation device 11a) is activated to generate a random number and generate a transmission ID (S11, S12). ). The random number is generated based on information included in the profile data, for example, date of birth, gender, contact information, and the like. Receive ID
Is substituted for all zeros (S13). Next, a checksum is calculated (S14), and a message is constructed by assembling the transmission ID, the reception ID, the profile data, the text body, and the checksum (S15). Next, it is determined whether a message has been received from another portable communication device (S16). Checking whether a message is received is performed by monitoring in a window of a data transmission period of 2 bytes. Actually, the reception of the message is determined by looking at the interrupt caused by receiving the data of one byte (11-bit sequence). The difference between the transmission timing of the message transmission side and the detection timing of the message detection side is monitored during a data communication period of 2 bytes in consideration of a window of at most 1 byte.

In step S16, when data is being received, the process of step S16 is repeated. When data is not received, a random number is generated (S1
7), a timer is preset with the value of this random number, and the process waits for a random time (S18). After the elapse of the random time, the presence / absence of the received message is determined again (S19). This makes it possible to stochastically avoid collision even when a plurality of communication devices are waiting for the end of message transmission by another communication device. If there is a communication device for which the random time has passed before, the received message is detected in step S19. In this case, a random number is generated (S20),
The timer is preset with the value of this random number, and waits for a random time (S21). When the timer expires, the process returns to step S16. If there are no incoming messages,
The own message is transmitted (S22). After the timer measures 10 seconds (S23), step S1 is executed.
6 and the process is repeated. The clocking process in step S23 operates with a low frequency clock to reduce power consumption.

As described above, the own message can be repeatedly transmitted.

In the mode in which the own message (normal message) is transmitted only once, the process ends in step S22. When transmitting a predetermined number of times, the number of times of transmission may be counted, and the transmission may be terminated when the count value reaches a predetermined value.

Transmission of a password message is also 1
It is transmitted once or a predetermined number of times. This is 1
It is processed like a normal message sent one or more times. However, a password is substituted for the reception ID instead of step S13 in FIG.

Next, the reply message transmission process will be described.

FIG. 6 shows a reply message transmission process. In FIG. 6, parts corresponding to those in FIG. 5 are denoted by corresponding reference numerals. It is assumed that the text of the reply message has already been input by the operator.

In the transmission process of the reply message, the transmission ID of the received message to be returned is directly used as the transmission ID of the reply message (S24). Next, a random number is generated, and this random number is used as a reception ID (S25, S26),
Further, a checksum is calculated and a message is assembled (S14, S15). The operations in steps S14 to S21 are the same as the operations in FIG. 5, and description thereof will not be repeated. In this example, the reply message is transmitted only once. However, it may be transmitted a plurality of times.
The transmission of the reply message may be prioritized over the reception of the message. In this case, the reception operation is made to wait until the transmission processing of the reply message is completed.

Next, the receiving operation will be described. FIG.
Indicates a receiving operation. In this figure, first, it is repeatedly checked whether a message has been received (S31). Next, the communication ID of the received message is checked (S32). If the received ID is a random number held by the user (including a random number used in the past), all zeros or a password held by the user, a reply message related to the reply message sent by the user,
It is determined that the message is transmitted from the other party to an unspecified person or a password message, and the message is regarded as valid. If the transmission ID is a random number held by the user (including a random number used in the past), the transmission ID is determined to be a reply message to a message automatically sent by the user, and
Make the message valid. If the message is valid, sound a buzzer, display a receive icon,
The message is stored (S33, S34, S35).
If it is determined that the message is not valid, the message is discarded (S36). Messages with the same communication ID are overwritten and updated.

Further, the messages stored in the message bank can be displayed on the liquid crystal display device 2 based on a predetermined calling operation. The message is replied to the displayed message.

FIG. 8 is a diagram for explaining an example of how the communication ID changes. In this figure, there are communication devices A, B, C,. ,
B, C... N are transmitting automatic transmission messages.
In this example, it is assumed that the transmissions of the device A and the device B are performed effectively without collision, and the device B and the device C receive the data successfully. In this message (A, B), the transmission ID is a value of a random number, and the reception ID is all zero. Receive ID
Are all zero, the other communication devices (B, C) determine that this is a new automatic transmission message and receive this message. At this time, it is assumed that the communication device B replies to the message from the device A. The communication device B keeps the transmission ID as the transmission ID (random number (A)) of the previous message,
A reply message with the reception ID as its own random number is transmitted. Since the random number of the communication device A is the same as the transmission ID of the reply message, it is received as a valid message. Other communication devices often discard the reply message because their random numbers do not match the transmission ID and the reception ID of the reply message. The probability that the random number of the other communication device matches the transmission ID or the reception ID of the reply message is not zero, but is extremely low, so there is no problem in ignoring it. Communication device A
If you want to reply further to the reply message,
The reception ID does not change as the transmission ID. Therefore, the communication device B receives this reply message as valid. Thereafter, communication is performed between the communication device A and the communication device B under the same transmission ID and reception ID.
This is as if a call were being set up.

Similarly, communication is performed between the communication devices B and C.

FIG. 9 shows a mode of transmitting and receiving a password message. In this example, it is assumed that the communication devices A and C hold the same password X. Assume that communication device A transmits a password message. In this case, the transmission ID
Is a random number of the communication device A, and the reception ID is a password X. The communication device B does not hold the password X, and the fact that its random number matches the transmission ID can be ignored in probability, and discards the password message. Since the communication device C has the same password X as the reception ID, the communication device C receives the message as valid. The reply to the password message is performed by sending the message with the random number included in the reception ID as in the case of the normal message. When the communication device C wants to transmit not only to the communication device A but also to another communication device sharing the password, the communication device C transmits a message using the reception ID as a password.

As described above, according to this embodiment, the communication I
D can be used to reply to the message. In addition, the reception ID is set to all zeros for a new message, so that the reception side can easily determine that the message is a new message. Further, as for the password message, only the person sharing the password by putting the password in the reception ID can receive the message effectively.

Although the embodiments have been described in detail, the present invention is not limited to the above embodiments.
For example, in this embodiment, a portable communication device has been described as an example, but some of the communication devices may be of a stationary type. Also,
Although data is exchanged between an unspecified number of people using a dedicated portable communication device, a mobile computer, a mobile station such as a mobile phone, a wireless transceiver, or the like may have the same function as that of the embodiment. Furthermore, the new message and the password message are indicated by the reception ID, but may be indicated by another message field.

Further, in order to cope with the fact that the random number for the communication ID is updated, the random number used in the past may be stored in a ring buffer or the like so as to cope with a reply to a previously transmitted message. Good.

[0053]

As described above, according to the present invention, data can be exchanged between an unspecified number of persons, and a reply to a message can be easily made.

[Brief description of the drawings]

FIG. 1 is a plan view showing an appearance of a portable communication device according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating an internal configuration of the portable communication device.

FIG. 3 is a diagram illustrating a mode of communication of the portable communication device.

FIG. 4 is a diagram illustrating a format example of a message transmitted and received by the portable communication device.

FIG. 5 is a flowchart illustrating an automatic message transmission operation of the portable communication device.

FIG. 6 is a flowchart illustrating a reply message transmission operation of the portable communication device.

FIG. 7 is a flowchart illustrating a receiving operation of the portable communication device.

FIG. 8 is a diagram illustrating an example of an automatic message transmission operation and a response message transmission operation of the portable communication device.

FIG. 9 is a diagram illustrating, by way of example, a password message transmission operation and a reply message transmission operation of the portable communication device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Portable communication device 2 Liquid crystal display device 3 Power button 4 Key group 5 Light emitting diode 11a Random number generator

Claims (8)

[Claims] 1. A communication device for transmitting and receiving a message using a wireless signal, a means for generating a random number, a means for incorporating an identifier composed of the random number into a message to be transmitted, and a reply message for a message received from a partner transmitting device. Means for incorporating, in addition to the identifier consisting of the random number, an identifier consisting of a random number generated by the other party's transmitting device and incorporated in the received message, in the reply message; Communication means for transmitting a self-addressed message, means for receiving the message, and means for determining, when the received message includes an identifier consisting of a random number generated by itself, a reply message addressed to itself. apparatus. 2. A communication device for transmitting and receiving a message by a wireless signal, comprising: a means for generating a random number; a message having an unspecified address; an identifier including a random number generated by itself; An identifier consisting of a value is included in the message, and an identifier consisting of a random number generated by the sender and an identifier consisting of a random number incorporated in the original message at the sender are included in the reply message returned to the sender. Means for incorporating, means for transmitting a message incorporating the identifier, means for receiving the message, and when the identifier included in the received message includes the identifier having the specific value, the destination is an unspecified message. Judgment, if the received message contains a self-generated random number identifier, reply to itself Communication apparatus characterized by comprising a means for discriminating a message. 3. A message to be transmitted to one or more specific destinations using a password includes an identifier including the password in the message instead of a specific value indicating that the destination is unspecified. 3. The communication apparatus according to claim 2, wherein when the identifier included in the received message corresponds to its own password, the communication apparatus determines that the message is addressed to itself. 4. The communication device according to claim 1, wherein the random number is generated based on profile information stored in a communication device main body.
Or the communication device according to 3. 5. The communication device according to claim 4, wherein the profile information includes at least one of a user's date of birth, gender identification, and contact information. 6. A system according to claim 1, further comprising means for storing a plurality of random numbers generated in the past, and determining whether or not the message is addressed to itself based on the plurality of stored random numbers.
The communication device according to 4 or 5. 7. A communication device for transmitting and receiving a message by a wireless signal, comprising: a random number generating unit; a unit for incorporating an identifier composed of a random number generated by the random number generating unit into a message to be transmitted; When transmitting a reply message to the message, in addition to the identifier consisting of the random number, an identifier consisting of a random number generated in the other party transmitting device and incorporated in the received message, means for incorporating in the reply message, Means for transmitting a message incorporating the identifier at a timing determined by the random number generated by the random number generating means, means for receiving the message, and when the received message includes an identifier composed of a random number generated by itself, Means for determining a reply message addressed to Communication device. 8. A communication device for transmitting and receiving a message by wireless signal, means for transmitting a message including its own identifier, means for receiving the message, and assembling a reply message so as to include the identifier included in the received message. And a means for determining whether the received message is a reply message addressed to itself based on an identifier included in the received message.