JP2005142815A - Communication system, communication device, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication system which can shorten a communication time. <P>SOLUTION: The system comprises two or more communication devices 12 and 13 which scan a plurality of predetermined channels; and the communication device 12 transmits a transmit signal having an information part including data after transmitting a preamble part including a bit synchronizing signal, a frame synchronizing signal, and opposite-party information repeatedly N times by using one of the plurality of channels, the communication device 13 recognizes that the signal is addressed to itself from opposite-party information included in the transmit signal, and then the communication devices 12 and 13 perform specified communication with each other by using only the channel used for the communication of the transmit signal. Consequently, when the frequency of communication becomes large, the frequency of repetition of the preamble signal is decreased to shorten the communication time for efficient communication. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention particularly relates to a communication system, a communication apparatus, and a program that constitute a home network at home.

  In recent years, white appliances such as air conditioners and refrigerators, security devices such as intrusion sensors, and home controllers installed in the home are connected wirelessly and connected to a mobile phone via the home controller. In-home network systems have been developed that control devices such as air conditioners and notify home security information through mobile phones. In such a home network system, a plurality of channels are generally assigned to the same system in consideration of jamming waves (see, for example, Patent Document 1).

  FIG. 5 shows a communication message format used in a conventional communication system, in which a preamble signal (1) 24a, a preamble signal (2) 24b, and a preamble signal (3) 24c are repeatedly transmitted. Each of the preamble signals (1) to (3) includes a first bit synchronization signal 21, a first frame synchronization signal 22, a control code 90, and a partial identification code 91, respectively. After the preamble signal is repeated, a second bit synchronization signal 60, a second frame synchronization signal 61, a control code 92, a partial identification code 93, and a data signal 62 are transmitted as the information unit 70. Yes.

  FIG. 6 illustrates an operation when a communication device waiting for multi-channel reception receives a signal having the above-described message structure.

  In FIG. 6, the sender A performs wireless transmission in order to communicate with a third party using 1ch. Then, the sender B wirelessly transmits to the receiver C a signal having the message structure shown in FIG. The receiver C carries out carrier sense alternately for 1ch and 2ch, and confirms the presence or absence of the carrier. Then, as shown in FIG. 6, for example, when carrier transmission is performed on the transmission signal of the sender A on 1ch, reception on is continued for a short time in order to determine whether the transmission is to the own station. If it is determined that it is not addressed to its own station by comparing and comparing the received partial identification code 91 or partial identification code 93 with its own identification code, the reception is switched to 2ch and carrier detection is performed. Then, in 2ch, if it is determined that it is addressed to the own station by the partial identification code in the preamble signal included in the signal of the sender B, the reception is continued to the end.

In order to receive the preamble signal 24, it is necessary to generate a sampling clock with the first bit synchronization signal 21 and to synchronize the frame with the first frame synchronization signal. Then, the receiver C needs time to determine that it is not addressed to itself by receiving 1ch, and it is uncertain at which timing it starts to receive 2ch. Therefore, the preamble signal is repeatedly transmitted N times.
JP 2000-270041 A

However, in the conventional configuration, when a plurality of messages are exchanged between the sender B and the receiver C, that is,
Communication (1): After sending a message from sender B to receiver C,
Communication (2): A response message is transmitted from the receiver C to the sender B.
Communication (3): Communication (2) where sender B sends a further message to receiver C (4): Consider the case where communication (2) and communication (3) are repeated several times thereafter.

  In all the messages of communication (1) to communication (4), it was necessary to repeat the preamble signal N times. For this reason, there is a problem that it takes a long communication time when the number of communication between the sender B and the receiver C increases (for example, the number of repetitions of communication (4) increases).

  In order to solve this problem, if the number of channels waiting for reception is set to 1 from the beginning of communication (1), communication is not possible if there is interference in the one channel. Challenges arise.

  The present invention solves the above-described conventional problem, and communication (1) performs communication by selecting an empty channel from among a plurality of channels, and communication (2) and thereafter are free from interference used in communication (1). An object of the present invention is to provide a communication system, a communication device, and a program capable of performing communication while fixing a channel to a communication channel, and at the same time, reducing the number of repetitions of a preamble signal and shortening the communication time.

  In order to solve the above-described conventional problems, the communication system of the present invention includes two or more communication devices that scan a plurality of predetermined channels, and the communication device A in each of the communication devices includes: A transmission signal having an information portion including data is transmitted after repeatedly transmitting a preamble portion including a bit synchronization signal, a frame synchronization signal, and destination information using a single channel among a plurality of channels, and each of the communication The communication device B in the device receives a signal by switching a plurality of channels, and determines whether the signal is addressed to the own station based on the other party information included in the transmission signal. Then, the communication device A and the communication device B indicates that predetermined communication is performed between the communication device A and the communication device B using only the channel used for communication of the transmission signal.

  As a result, when the number of times of communication increases, the number of repetitions of the preamble signal can be reduced to shorten the communication time.

  The communication apparatus of the present invention transmits a channel scanning means for scanning a plurality of channels, and an information portion including data after a preamble portion including a bit synchronization signal, a frame synchronization signal, and partner information is repeatedly transmitted N times. Receiving means for receiving a signal to be transmitted, periodically scanning a plurality of channels by the channel scanning means, and receiving the signal addressed to the own station by means of the destination information included in the preamble part by the receiving means. The operation of the channel scanning means is stopped, and predetermined communication is performed on the channel that has received the signal addressed to the own station.

  As a result, it is possible to realize a communication device that can transmit and receive with a simple configuration even when the number of repetitions of the preamble signal is small.

  Further, the program of the present invention causes a computer to realize at least a part of the functions of the communication system and the communication device.

  Thus, the functions of the communication system and the communication device can be realized with simple hardware.

  The communication system, communication device, and program of the present invention can reduce the number of repetitions of the preamble signal and reduce the communication time when the number of times of communication is increased, thereby enabling efficient data communication.

  The first invention is composed of two or more communication devices that scan a plurality of predetermined channels, and the communication device A in each communication device uses one channel among the plurality of channels. Transmitting a transmission signal having an information portion including data after repeatedly transmitting the preamble portion including the bit synchronization signal, the frame synchronization signal, and the destination information N times, and the communication device B in each of the communication devices includes a plurality of The communication device A and the communication device B use the channel used for communication of the transmission signal after determining whether or not the signal is addressed to the local station based on the destination information included in the transmission signal after switching the channel. If the number of communications increases by using a communication system in which predetermined communication is performed between the communication device A and the communication device B using only the The communication signal can be shortened and the communication time can be shortened.

  In the second invention, in particular, in the first invention, the number of repetitions of the preamble portion transmitted in the predetermined communication between the communication device A and the communication device B is smaller than the number of repetitions N of the preamble portion of the transmission signal. Thus, after receiving the first message, the number of repetitions of the preamble signal of the message to be transmitted / received can be reduced, and efficient transmission to the communication partner can be performed.

  In a third aspect of the invention, in particular, in the first or second aspect of the invention, the communication apparatus B has carrier sense means for detecting the presence or absence of a carrier signal, and a transmission signal from the communication apparatus A using the carrier sense means. By starting the reception of the preamble part included in the transmission signal only when the signal is detected, wasteful reception due to noise can be prevented, and an efficient communication system can be realized.

  The fourth invention is a signal for transmitting a channel scanning means for scanning a plurality of channels, an information portion including data after a preamble portion including a bit synchronization signal, a frame synchronization signal, and partner information is repeatedly transmitted N times. The channel scanning means periodically scans a plurality of channels, and when the receiving means receives a signal addressed to its own station according to destination information included in the preamble part, the channel scanning is performed. Even if the number of repetitions of the preamble signal is small with a simple configuration, the operation of the means is stopped and the communication device is configured to perform predetermined communication on the channel that has received the signal addressed to the own station. A communication device capable of reliably transmitting and receiving can be realized.

  In particular, the fifth invention is characterized in that, in the fourth invention, there is provided transmission means for transmitting an information part including data after a preamble part including a bit synchronization signal, a frame synchronization signal and destination information is repeatedly transmitted N times. By reducing the number of repetitions of the preamble portion of the signal transmitted by the transmission means in the predetermined communication on the channel that has received the signal addressed to the station, less than the number of repetitions N of the preamble portion included in the signal received by the reception means, With a simple configuration, the number of repetitions of the preamble signal can be reduced, and a communication device that can reliably transmit and receive even when the number of repetitions of the preamble signal is small can be realized.

  The sixth invention has carrier sense means for detecting the presence / absence of a carrier signal, particularly in the fourth or fifth invention, and when a carrier is detected in a channel with the carrier sense means while scanning a plurality of channels. By starting the receiving means and starting the receiving operation on the channel where the carrier is detected, it is possible to prevent useless reception due to noise and to realize an efficient communication apparatus.

  The seventh invention is a program for causing a computer to realize at least part of the functions of the communication system and the communication device according to any one of the first to sixth inventions, so that the communication system and The function of the communication device can be realized.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment)
FIG. 1 shows a communication apparatus according to an embodiment of the present invention.

  In the figure, an antenna 1 is connected to a transmission means 2 and a reception means 3. The code generation means 4 and the code decoding means 5 are connected to the home appliance 9. The wireless communication unit 6 includes a transmission unit 2, a reception unit 3, a code generation unit 4, and a code decoding unit 5. The carrier sense unit 7 and the channel scan unit 8 are connected to the wireless communication unit 6 and constitute a communication device 10 together with the wireless communication unit 6.

  By the operation of the channel scanning means 8, the communication device 10 sequentially scans the three channels, and when the carrier is detected in the channel scanned by the carrier sensing means 7, it is determined whether the radio wave is addressed to the own station on the carrier detected channel. Is decoded by the decoding means 5, and if it is addressed to the own station, the reception is continued, and if not addressed to the own station, the next channel is scanned.

  FIG. 2 shows an example of a communication system using the communication apparatus in this embodiment.

  In the figure, a block composed of the communication processing unit 11 and the communication device A12 is a home controller, and a block composed of the communication device B13 and the air conditioner 14 is a network-compatible home appliance controlled by the home controller. Although not shown in FIG. 2, the home controller has a touch panel and can control the air conditioner 14 by pressing a button on the touch panel. The communication device A12 constituting the home controller and the communication device B13 connected to the air conditioner 14 are connected by a protocol using a specific low power radio wave of 429 MHz band.

  The communication device A12 or the communication device B13 in FIG. 2 corresponds to the communication device 10 in FIG. The communication processing unit 11 or the air conditioner 14 in FIG. 2 corresponds to the home appliance 9 in FIG.

  Here, the message structure transmitted and received between the communication device A12 and the communication device B13 in FIG. 2 will be described with reference to FIG.

  In FIG. 3, (1) shows the entire data format configuration. In (1) of FIG. 3, section (a) is called a preamble part, and is set to one (bit synchronization signal 1 + frame synchronization signal 1 + data signal 1) in order to cope with a reception method in which a plurality of channels are sequentially scanned and waited. This block is repeatedly transmitted N times as one block. For example, when the receiving side sequentially scans and waits for three channels, two blocks are required for each channel, and thus the block is repeated six times. The section (B) is an information part including data. The section (c) is a signal indicating the end of transmission, but may not be present.

  The detailed configuration of data 1 is shown in (2) of FIG. The detailed configuration of data 2 is shown in (3) of FIG. The data 1 includes destination information, that is, a receiving device identification code indicating a destination, and a partial wireless system identification code that is a part of a wireless system identification code that identifies whether the system belongs to itself. The partial radio system identification code is a radio system identification code divided into three parts. Data 2 includes a wireless system identification code and a transmission device identification code indicating a transmission source. Whether it is a message of the system to which it belongs is determined by a wireless system identification code, and whether it is a broadcast is determined by a certain bit of the control code 1 and the pattern of the receiving device identification code.

  The operation and action of the communication apparatus configured as described above will be described below with reference to FIG.

  FIG. 4 is a diagram for explaining the operation of the communication device and the home appliance shown in FIGS. 1 and 2.

  Here, a sequence for turning on the operation of the air conditioner 14 from the communication processing unit 11 of the home controller and notifying the communication processing unit 11 that the air conditioner 14 has been turned on will be described.

  The communication processing unit 11 transmits a request message 15 “Please turn on the air conditioner” to the communication device A12.

  Then, the communication device A12 wirelessly transmits a request message 16 that the air conditioner is ON with the message configuration shown in FIG. At this time, the preamble portion (section (a) in FIG. 3) of the air conditioner ON message 16 transmitted from the communication device A12 corresponds to the three channel reception waiting of the communication device B13 of the communication partner (bit synchronization signal 1 + frame synchronization signal). The block of 1 + data signal 1) is repeated 6 times.

  When the air conditioner ON message 16 is received by the communication device B13, ACK 17 is wirelessly transmitted, and the air conditioner ON message 18 is transmitted to the air conditioner 14.

  When the air conditioner 14 receives the air conditioner ON message 18, the air conditioner 14 starts the air conditioning operation. Then, the air conditioner 14 transmits a response message 19 for notifying the home controller that the air conditioning operation has started, to the communication device B13.

  Now, after transmitting the air conditioner ON 16, the communication device A 12 stops the channel scan operation by the operation of the channel scan means 8 shown in FIG. In other words, it waits for reception on the channel that transmitted the air conditioner ON message 16.

  On the other hand, when the communication device B13 receives the air conditioner ON message 16, the communication device B13 stops the channel scan operation by the operation of the channel scan means 8 shown in FIG. That is, ACK 17 is wirelessly transmitted on the channel that received the air conditioner ON message 16.

  In the wireless transmission of the ACK 17, the number of repetitions of the (bit synchronization signal 1 + frame synchronization signal 1 + data signal 1) block of the wireless transmission message preamble part is switched to two times corresponding to the reception side 1-channel reception standby.

  The number of block repetitions (bit synchronization signal 1 + frame synchronization signal 1 + data signal 1) of the response message 20 wirelessly transmitted from the communication apparatus B13 is also two times corresponding to the standby for one channel. And since communication apparatus A12 is in the 1-channel standby state, it can receive even if the number of preamble repetitions of response message 20 is two, and transmits ACK21. Of course, the number of preamble repetitions for ACK 21 is also two. Then, the communication device A12 transmits a response message 22 to the communication processing unit 11.

  To summarize the above, section 1, section 2, and section 3 show the difference in the number of channels waiting for reception of the communication device A12. State.

  Section 4, section 5, and section 6 show the difference in the number of channels waiting for reception of the communication apparatus B13. Section 4 and section 6 are in a 3-channel reception standby state, and section 5 is in a 1-channel reception standby state.

  The end of section 2 or section 5 is defined by timeout T1 or timeout T2. The communication device A12 and the communication device B13 each have timer means (not shown in FIG. 1). The timer means is restarted every time the message shown in FIG. 3 is wirelessly transmitted or received, and the timeout time is extended. Timeout T1 is activated during wireless transmission, and timeout T2 is activated during wireless reception. Accordingly, if wireless communication occurs within the timeout time T1 or T2 between the communication device A12 and the communication device B13, the one-channel reception standby state is continued.

  Note that by setting the timeout T1 to be longer than the timeout T2, even if the response message 19 is generated in the section 3 in which the communication device A12 returns to the 3-channel reception standby state, the communication device B13 is already 3 The section 6 corresponds to channel reception standby, and the communication device B13 can reliably receive the response message 20.

  Further, the timeouts T1 and T2 are set assuming a time when a response message from the air conditioner 14 returns in a series of communications. After the end of the series of communication, when the timeouts T1 and T2 are exceeded, the section 3 and the section 6 are returned. Therefore, even if a jamming wave is generated in the channel used in the sections 2 and 5, the section 3 and section 6 can communicate.

  In addition, the change from section 1 to section 2 or the change from section 4 to section 5 is the time of wireless transmission or the time of wireless reception, but the above-mentioned section change is performed depending on the type of message transmitted and received wirelessly. You may do it. For example, when a bit indicating a link connection telegram is provided at the control code 1 shown in FIG. 3 (a) and it is desired to change from section 1 to section 2, the bit is set and transmitted, and the communication device B13 changes from section 4 to section 5 when a signal with the bit set is received.

  Moreover, although the case where the change from the section 2 to the section 3 or the change from the section 5 to the section 6 is performed with a timeout has been described, the above-described section change may be performed depending on the type of telegram transmitted and received wirelessly. . For example, when a bit indicating a link disconnection telegram is provided at the control code 1 shown in FIG. 3A and it is desired to change from the section 5 to the section 6, the bit is set and transmitted. When A receives the signal with the bit set, it changes from section 2 to section 3.

  The link connection signal and the link disconnection signal can be transmitted from either the communication device A12 or the communication device B13.

  Further, at least a part of the functions of the communication system and the communication device described above can be executed by a computer program. Thus, the functions of the communication system and the communication device can be realized with simple hardware.

  In this embodiment, switching from 3-channel communication to 1-channel communication has been described as an example. However, the present invention is not limited to this number of channels. It is good.

  Further, the communication system may include two or more communication devices that scan a plurality of predetermined channels, and is not limited to the embodiment.

  As described above, the communication system, the communication apparatus, and the program according to the present invention can reduce the number of repetitions of the preamble signal and reduce the communication time when the number of times of communication increases, so that efficient data communication can be achieved. This is useful not only for home networks at home, but also as a communication system or communication device for performing data communication.

The block diagram of the communication apparatus in embodiment of this invention Block diagram of a communication system using the communication device The figure which shows the data format which the same communication equipment transmits The figure explaining operation of the communication device The figure which shows the data format which the conventional communication apparatus transmits The figure explaining operation | movement of the conventional communication apparatus

Explanation of symbols

2 Transmitting means 3 Receiving means 6 Wireless communication unit 7 Carrier sense means 8 Channel scanning means 9 Home appliance 10 Communication device 11 Communication processing unit 12 Communication device A
13 Communication device B
14 Air conditioner

Claims (7)

It is composed of two or more communication devices that scan a plurality of predetermined channels, and the communication device A in each of the communication devices uses a single channel in the plurality of channels to transmit a bit synchronization signal and a frame. After repeatedly transmitting the preamble part including the synchronization signal and the destination information N times, a transmission signal having an information part including the data is transmitted, and the communication apparatus B in each of the communication apparatuses receives a signal by switching a plurality of channels. After determining whether or not the signal is addressed to the local station from the destination information included in the transmission signal, the communication device A and the communication device B use only the channel used for communication of the transmission signal. A communication system configured to perform predetermined communication between the communication device A and the communication device B. The communication system according to claim 1, wherein the number of repetitions of the preamble part transmitted in the predetermined communication between the communication apparatus A and the communication apparatus B is smaller than the number of repetitions N of the preamble part of the transmission signal. The communication device B has carrier sense means for detecting the presence / absence of a carrier signal, and starts receiving the preamble portion included in the transmission signal only when the carrier sense means is used to detect the transmission signal from the communication device A. The communication system according to claim 1 or 2. Channel scanning means for scanning a plurality of channels, and receiving means for receiving a signal for transmitting an information portion including data after a preamble portion including a bit synchronization signal, a frame synchronization signal, and destination information is repeatedly transmitted N times The channel scanning means periodically scans a plurality of channels, and the receiving means stops the operation of the channel scanning means when receiving a signal addressed to the own station by the destination information included in the preamble part. A communication apparatus configured to perform predetermined communication on a channel that receives a signal addressed to the own station. In a predetermined communication on a channel that has received a signal addressed to its own station, it has transmission means for transmitting an information portion including data after repeatedly transmitting a preamble portion including a bit synchronization signal, a frame synchronization signal, and destination information N times. 5. The communication apparatus according to claim 4, wherein the number of repetitions of the preamble part of the signal transmitted by the transmission unit is less than the number of repetitions N of the preamble part included in the signal received by the reception unit. A carrier sense means for detecting the presence or absence of a carrier signal is provided. When the carrier sense means detects a carrier in a channel that is scanning a plurality of channels, the receiving means is activated and the reception operation is started in the channel in which the carrier is detected. The communication device according to claim 4 or 5. The program for making a computer implement | achieve at least one part of the function of any one of Claims 1-6.

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