JP2006033490A - Data communication device, and communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data communication device and a communication system in which a communication speed does not decrease even if the number of the communication devices increases. <P>SOLUTION: The data communication device 1 is connected to a higher rank device 2, and performs data communication between the higher rank device 2 and a central control device 6 through a radio communication network of. It is provided with a predetermined time setting part 14 which establishes a time range in which data communication can be performed, a random data generation part 125 which creates random values, a time part 13 with a clock function, and a communication time zone determination part 123 which decides a communication time slot in which radio data communication is carried out in a time range which is set by the predetermined time setting part 14 following to random values generated by the random data generation part 125; and starts radio data communication when time outputted from the time part 13 and communication time zone outputted from the communication time slot determination part 123, are agreed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a data communication device and a communication system, and particularly relates to a technology of a data communication device using radio.

Communication devices that transmit and receive data wirelessly via a public network are known and may be used in monitoring devices. There exists patent document 1 etc. as an example of the remote monitoring system etc. which used these communication apparatuses. The above communication device uses wireless communication and has relatively less difficulty in constructing facilities such as laying a communication line than in the case of wired communication, so that it is easy to provide a large number of communication devices, etc. There is.
JP 2004-62444 A JP 2003-85075 A JP-A-11-109047

  However, in the above-described conventional technology and the like, even if the communication time width is limited, if a large number of communication devices are provided, the number of communication devices increases in the central control device that transmits and receives various data to and from each communication device. In some cases, the process may not be performed normally, resulting in a problem. For example, when the time periods for transmission and reception of each communication device overlap, the amount of data increases significantly and exceeds the allowable amount of the line, the communication speed decreases and the communication delay increases, and in the worst case communication is performed. It is a phenomenon that it becomes impossible. In order to avoid such a problem, it is generally sufficient to increase the capacity of a line through which data is communicated. However, there is a problem that the cost of equipment is increased (see Patent Documents 2 and 3).

  Accordingly, an object of the present invention is to provide a data communication apparatus and a communication system in which the communication speed does not decrease even if the number of communication apparatuses increases.

  In order to solve the above problems, the present invention prevents a plurality of communication devices from concentrating and communicating with the central control device at the timing when the central control device and the communication device communicate. Therefore, when the central control device and the communication device communicate with each other within a predetermined time, it is determined that each communication device itself communicates with the central control device so that the time zone for communication is distributed. Is to make it.

  That is, the present invention is a data communication device that is connected to a host device and performs data communication between the host device and the central control device via a wireless communication network, and sets a time range in which data communication can be performed. A predetermined time setting unit, a random data generating unit for generating a random value, a time unit having a clock function, and a time set by the predetermined time setting unit according to the random value generated by the random data generating unit A communication time zone determining unit for determining a communication time zone for performing wireless data communication within a range, and when the time output by the time unit matches the communication time zone output by the communication time zone determining unit, A data communication device that starts wireless data communication.

  In addition, the present invention transmits a request signal to the host device when the time output by the time unit matches the communication time zone output by the communication time zone determination unit, and is activated by the request signal. This is a data communication device that performs wireless data communication between the higher-order device and the central control device.

  Then, the present invention receives a start signal from the host device, starts data communication operation with the host device, stores the received communication data in a buffer memory unit that temporarily stores the data, and outputs the time unit The data communication device transmits the data stored in the buffer memory unit to the central control device when the time and the communication time zone output by the communication time zone determination unit coincide.

  Furthermore, the present invention is a data communication apparatus that changes a communication time zone output from the communication time zone determination unit at a predetermined period or at an arbitrary timing.

  The present invention also provides a communication comprising: a host device, a central control device, and a data communication device connected to the host device and performing data communication between the host device and the central control device via a wireless communication network. The system includes a plurality of the data communication devices, and at least one of the data communication devices is a communication system that is one of the data communication devices described above.

  According to the present invention, when various types of data are transmitted and received between the central control device and the communication device, conventionally, there are cases where the communication speed decreases and communication processing cannot be performed normally due to an increase in the number of communication terminals. However, this problem can be solved without increasing the capacity of the communication line.

The best mode for carrying out the present invention will be described.
Hereinafter, examples which are embodiments using the present invention will be described with reference to FIGS. FIG. 1 is a configuration diagram of the data communication apparatus according to the first embodiment. FIG. 2 is an overall configuration diagram of a communication system using the data communication apparatus of the present invention. FIG. 3 is an explanatory diagram of an example of a flow for determining a communication time zone in the data communication apparatus according to the first embodiment. FIG. 4 is an explanatory diagram of an example of a flow processed by the data communication apparatus according to the first embodiment. FIG. 5 is an explanatory diagram of timings at which a plurality of data communication apparatuses according to the first embodiment communicate. FIG. 6 is a configuration diagram of the data communication apparatus according to the second embodiment. FIG. 7 is an explanatory diagram of an example of a flow processed by the data communication apparatus according to the second embodiment.

  Example 1 will be described. An overall configuration of a data communication system according to an embodiment of the present invention will be described with reference to FIG. This system is an example of a remote monitoring system that performs data communication between n number of host devices 2 and a central control device 6 using radio. The data communication device 1_i (i is 1 to n) connects the data of the host device 2_i to which it corresponds to the public line network 4 wirelessly by the antenna 3_i, and from the public line network 4 through the dedicated line 5 The system communicates with the control device 6. Therefore, the data of all the host devices 2_i are processed in the public line network 4, the dedicated line 5, and the central control device 6.

  Next, the configuration of the data communication apparatus 1 will be described with reference to FIG. The data communication apparatus 1 has a configuration using a microcomputer 12 (hereinafter abbreviated as “microcomputer”), and the blocks shown in the microcomputer 12 are processed by software. First, communication data 21 with the host device 2 is transmitted via the interface unit 11, and transmission / reception control is performed by the communication control unit 121. Received data from the host device 2 is converted into a format that allows the protocol converter 122 to communicate with the public line network 4 and the central control device 6. This data is sent to the radio communication unit 15 controlled by the radio control unit 124, and is transmitted as a radio wave from the antenna 3 sent as the radio signal 151. Here, it goes without saying that the data received from the antenna 3 is sent to the host device 2 following the above-described path in reverse.

  An example of a timing determination method for performing the above-described transmission / reception processing will be described. The communication time zone determination unit 123 determines a communication time zone corresponding to an arbitrary value generated by the random data generation unit 125 within the range of the predetermined time set in the predetermined time setting unit 14. The time unit 13 has a clock function. When the time output by the time unit 13 matches the communication time zone determined by the communication time zone determination unit 123, the interface unit 11 sends a request signal 111 to the host device 2 to start the above-described communication processing.

  Hereinafter, an example of the process for determining the communication time zone performed by the microcomputer 12 in the first embodiment will be described with reference to the flowchart of FIG. First, in step 200, it is determined whether or not it is necessary to update the communication time zone determined at present, and if it is to be updated, the range of the predetermined time set in advance in step 202 is taken in. Thereafter, in step 204, random data is generated to determine arbitrary data. Here, there are various methods for generating random data, such as generating random numbers by themselves or using stored random numbers. In step 206, using this value, one time zone is determined within a predetermined time range and set as a communication time zone. If it is not necessary to change the communication time zone in step 200, the process is terminated as it is.

  According to the determination of the communication time zone by this processing, since the communication time zone can be updated periodically, it becomes difficult to specify the communication time zone from the outside, and an improvement in security can be expected. The communication time zone can be updated not only at a fixed period but also at an arbitrary timing.

  Next, an example of communication processing performed by the microcomputer 12 in the first embodiment will be described with reference to the flowchart of FIG. In step 300, the current time is fetched from the time unit 13, and it is determined in step 302 whether or not the time coincides with the communication time zone. If the current time is not in the communication time zone, the process ends. If it is in the communication time zone, the process proceeds to the data communication processing from step 304.

  First, in step 304, connection with the public line network 4 is established. After the line connection is established, the process proceeds to step 306 to establish line connection with the central controller 6. Here, as a connection method with these lines, there is a connection method using a standard protocol such as PPP connection or TCP / IP connection. After data communication with the central control device 6 becomes possible in this way, in step 308, the host device 2 is activated to request data.

  Thereafter, if there is data for the central control device 6 received from the host device 2 in the determination in step 310, protocol conversion is performed in step 312 so that the data is in a data format that allows data communication with the central control device 6. The protocol conversion data is wirelessly transmitted at step 314 to end the transmission process, and the process proceeds to the next step 316 reception process. At this point, the data of the host device 2 is sent to the central control device 6 via the public line network 4. If it is determined in step 310 that there is no data received from the higher-level device 2, the process directly proceeds to the reception process in step 316.

  In step 316 of the reception process, the presence / absence of reception data from the wireless communication unit 15 is determined. If data is received, the received data is converted into a protocol in step 318. Note that the protocol conversion performed in step 318 is the reverse of the conversion process in step 312. The data subjected to the reverse protocol conversion is transmitted to the host device 2 in step 320, and a series of transmission processing is completed. If there is no data received from the wireless communication unit 15 in the determination in step 316, the process proceeds to step 322 as it is.

  In step 322, it is determined whether or not a series of transmission / reception processing has been completed, such as confirmation of the presence or absence of uncommunication data received from the host device 2. . On the other hand, if the communication process is completed in step 322, the process proceeds to a line disconnection process. First, after the connection with the central control device 2 is cut off at step 324, the connection with the public line network 4 is cut off at step 326, thereby completing a series of communication processing.

  An example of the concept of timing at which each data communication device communicates when a plurality of data communication devices are used by the method described above will be described with reference to FIG. Each data communication apparatus determines one communication time zone within a predetermined time range set in accordance with the processing described with reference to FIG. Here, even if the set range of the predetermined time is common to each data communication device, the communication time zone of each data communication device is determined using random numbers within the time range, and thus is distributed. Is more likely. Since data is transmitted and received between the host device 2 and the central control device 4 at this communication timing, communication can be performed without increasing the capacity of the communication line.

  A second embodiment will be described with reference to FIGS. 6 and 7. The entire communication system of the present embodiment is the same as that of FIG. In the present embodiment, the start timing of data communication is given from the data communication device 1 to the host device 2 in the first embodiment, but the host device 2 starts the data communication device 1 on the contrary. It is. That is, as shown in FIG. 6, the request signal 112 for starting data communication is output from the host device 2 to the data communication device 1. In the block diagram of FIG. 6, blocks having the same reference numerals as those in the block diagram of FIG. 1 have the same functions. The determination of the communication time zone with the central control device 6 is the same as in the first embodiment. For this reason, the timing of data communication performed by the data communication device 1 with the host device 2 and the timing of performing wireless communication with the central control device 4 are different. Therefore, a buffer memory 126 that temporarily stores communication data with the host device 2 is provided.

  Next, an example of communication processing performed by the microcomputer 12 will be described with reference to the flowchart of FIG. As described above, the determination of the communication time zone with the central controller 4 is the same as in FIG. The activation of this process is performed by a polling process with a fixed period or an interrupt process that can be activated externally. First, in step 400, the presence / absence of a request signal from the host device 2 is determined. If there is a request from the host device 2, the data from the host device 2 is stored in the buffer memory in step 402, and the process proceeds to step 404. If there is no request from the host device 2 in step 400, the process proceeds to step 404 as it is.

  In step 404, the current time is fetched from the time unit 13, and it is determined in step 406 whether or not the time coincides with the communication time zone. If the current time is not the communication time zone in step 406, the process is terminated. If it is the communication time zone, it is determined in step 408 whether there is data to be transmitted to the central control unit in the buffer memory. If there is no transmission data in step 408, the process is terminated as it is, but conversely, if data exists, the process proceeds to the data communication process from step 410 described below.

  In step 410, connection to the public line network 4 is made. After the line connection is established, the process moves to step 412 to establish line connection with the central controller 6. Here, it goes without saying that the connection method with these lines is the same as in the first embodiment. Thereafter, in step 414, protocol conversion is performed so that the data in the buffer memory is in a data format that allows data communication with the central controller 6. The protocol conversion data is wirelessly transmitted at step 416, thereby completing the transmission process. When the transmission is completed, the connection with the central control device 2 is cut off at the next step 418, and then the connection with the public line network 4 is cut off at the step 420, thereby ending the series of communication processing. In the second embodiment, the process of receiving data from the central controller 6 is the same as that in the first embodiment, and is not described.

  In the embodiment described above, the data communication timing is performed in the time zone determined by the data communication terminal 1, but it is necessary to urgently transmit / receive data to / from the central controller 6 including failure information from the host device 2. In this case, it goes without saying that transmission / reception can be performed without applying the activation timing of this embodiment.

  Even in the case where data communication is performed using a large number of communication devices in this way, by applying the above-described embodiments with a plurality of communication devices in the past, the central control device performs data communication simultaneously. It is possible to avoid delays in data transmission / reception speed and failure to communicate normally. In addition, the communication network used for data communication with a large number of communication devices can communicate even if the data communication capacity is smaller than the conventional one, and the processing capability of the control device for processing these communication data. There is an advantage that it can be realized while suppressing.

  In addition, according to the above embodiment, when the central control device and the communication device perform communication within a predetermined time, random data is generated when each communication device performs communication in a distributed manner. Since the communication allocation time of each communication device is not distributed at the timing by a program for scheduling, there is an advantage that distributed processing can be easily realized.

  Further, by not performing scheduling of communication time by a program, there is an advantage that the scheduling method does not need to be changed even when, for example, a large fluctuation occurs in the number of communication devices.

  In addition, since the communication timing of the communication device is determined by random data, for example, when acquiring data from a plurality of predetermined installation locations such as facility locking and safety information, the data can be acquired from random installation locations. Thus, it is possible to improve safety in terms of security as compared with the case where data is acquired at a timing determined under a predetermined rule.

  In addition, when the embodiment of the present invention is applied to a system that collects data from a system having a certain sample, data can be acquired by random sampling, and acquisition of the entire data for a so-called sample can be acquired in a short time. It is possible to provide a system that can provide advantages that can be achieved.

1 is a configuration diagram of a data communication apparatus according to a first embodiment. 1 is an overall configuration diagram of a communication system using a data communication apparatus of the present invention. FIG. 3 is an explanatory diagram illustrating an example of a flow for determining a communication time zone in the data communication apparatus according to the first embodiment. FIG. 4 is an explanatory diagram illustrating an example of a flow processed by the data communication apparatus according to the first embodiment. Explanatory drawing of the timing which several data communication apparatuses of Example 1 communicate. FIG. 3 is a configuration diagram of a data communication apparatus according to a second embodiment. FIG. 10 is an explanatory diagram of an example of a flow processed by the data communication apparatus according to the second embodiment.

Explanation of symbols

1 Data communication device 11 Interface unit 111 Request signal (from host device)
112 Request signal (to host device)
DESCRIPTION OF SYMBOLS 12 Microcomputer 121 Communication control part 122 Protocol conversion part 123 Communication time zone determination part 124 Wireless control part 125 Random data generation part 13 Time part 14 Predetermined time setting part 15 Wireless communication part 151 Wireless signal 2 Host apparatus 3 Antenna 4 Public line network 5 Dedicated line 6 Central control unit

Claims (5)

A data communication device that is connected to a host device and performs data communication between the host device and the central control device via a wireless communication network,
A predetermined time setting unit for setting a time range in which data communication can be performed, a random data generating unit for generating random values, a time unit having a clock function, and a random data generating unit for generating random values A communication time zone determining unit that determines a communication time zone for performing wireless data communication within a time range set by the predetermined time setting unit according to a value, and the time output by the time unit and the communication time zone determining unit are A data communication apparatus, wherein wireless data communication is started when an output communication time zone coincides. The data communication apparatus according to claim 1, wherein
When the time outputted by the time part matches the communication time zone outputted by the communication time zone determining unit, a request signal is transmitted to the higher-level device, and the higher-level device activated by the request signal and the above-mentioned A data communication apparatus that performs wireless data communication with a central control apparatus. The data communication apparatus according to claim 1, wherein
The activation signal from the host device is received, data communication operation with the host device is started, the received communication data is temporarily stored in the buffer memory unit, and the time output by the time unit and the communication time are stored. A data communication device characterized by transmitting data stored in the buffer memory unit to the central control device when the communication time zone output by the band determining unit coincides. The data communication apparatus according to claim 1, wherein
A data communication apparatus characterized in that the communication time zone output by the communication time zone determination unit is changed at a predetermined cycle or at an arbitrary timing. In a communication system comprising a host device, a central control device, and a data communication device connected to the host device and performing data communication between the host device and the central control device via a wireless communication network,
A communication system comprising a plurality of the data communication devices, wherein at least one of the data communication devices is the data communication device according to any one of claims 1 to 4.

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