JP5023842B2 - Wireless transmission device - Google Patents

Description

The present invention, when transmitting a wireless communication system, it relates to a radio transmitting apparatus that performs collision avoidance of a wireless communication by performing carrier sense.

  In a conventional wireless communication system, when performing communication between terminals, each terminal has a function to prioritize and transmit data according to data, and transmission priority when various kinds of data are transmitted between the transmitting terminal and the receiving terminal. A function for determining the order and a function for changing the transmission priority of data during data communication by transmitting command data for changing the priority of data transmission so that the data collide with each other or in a transmission waiting state. There are some that perform efficient communication.

  For example, there is a wireless communication system as shown in FIG. 7 for the purpose of preventing collision and waiting for transmission by providing transmission data priorities (for example, Patent Document 1).

  In FIG. 7, a centralized control station 1 having a wireless connection function between wireless terminals, a plurality of wireless dedicated telephones 12-A and 12-B that perform communication of control data and voice data, communication of control data and between terminals It comprises data terminal devices 13-A to 13-F that perform direct data communication.

  The operation will be described below.

  When data is transmitted from the centralized control station 1 to the plurality of radio dedicated telephones 12-A and 12-B and the data terminals 13-A to 13-F, carrier detection is performed for a certain time, and concentration is performed when there is no carrier. A carrier is transmitted from the control station 1.

  The wireless dedicated telephones 12-A and 12-B and the data terminals 13-A to 13-F, which are counterpart terminals that communicate with each other by the transmitted carrier, recognize transmission data to be sent later, and transmit data from the centralized control station 1 Receive.

By this method, the wireless dedicated telephones 12-A and 12-B and the data terminals 13-A to 13-F recognize that the carrier is transmitted in advance during data communication with high priority. Can be transmitted and received, and signal collision can be prevented.
JP-A-10-84307

  However, in the communication system described above, the carrier sense can be normally detected, and since there is always a delay time from the reception signal input to the carrier detection in both hardware and software, reception is performed from the timing transmitted by the wireless transmission device. There is a delay time until the device actually detects the carrier.

  Therefore, even if another wireless transmission device transmits within the delay time, carrier detection cannot be performed, so that most of the transmission signals collide with each other, and a failure occurs in which the reception device cannot receive only one of them.

Also, even though the wireless transmission device has a function to avoid collision by having carrier detection, transmission is performed at intervals because multiple wireless transmission devices operate depending on their timers or clock frequencies. Even if it is done, the deviation due to the tolerance of each timer or clock frequency is generated, the timing to collide is generated, and when there is a collision by transmitting once in the delay time, the deviation due to the tolerance will deviate from the delay time Since the carrier cannot be detected, there may be a long-term collision.

  Since such a collision occurs even in a combination of two wireless transmission devices, there is a problem that if the number of the devices is large, the probability of the collision is increased.

  The present invention solves the above-described conventional problems, and even when signals are transmitted from a plurality of wireless transmission devices within a delay time from signal input by hardware or software to carrier detection, the signal transmission timing The purpose is to suppress a long-term collision by deviating from the delay time for each transmission.

  In order to solve the above-described problems, in the present invention, a plurality of wireless transmission devices that perform carrier sense for collision prevention before transmission and perform periodic transmission, and the carrier sense unit of the wireless transmission device receives the signals. Delay time setting means for recording a delay time from input to carrier detection, identification means for identifying a plurality of wireless transmission devices, a wireless control unit for performing collision detection and transmission / reception control of transmission signals, and the identification at every transmission According to the identification value of the means, a correction means for shifting the transmission timing back and forth by an integral multiple of the delay time of the delay time setting means is provided.

  Thus, when a plurality of wireless transmission devices transmit simultaneously within the delay time, the time from the own transmission timing to the carrier detection of another signal is equal to or less than the delay time of the delay time setting means + the own transmission time The wireless control unit determines that there is a collision at the time of transmission, and the correction means transmits the transmission by shifting an integral multiple of the delay time during the next transmission, so that a short period of time can be obtained even if a transmission signal collision occurs. Thus, carrier detection can be performed and collision avoidance can be performed at an early stage.

  As described above, according to the present invention, the carrier sense unit of the wireless transmission device sets a delay time in advance in the delay time setting means for a plurality of signal collisions within the delay time from reception input to carrier detection, By shifting the time that is an integral multiple of the delay time back and forth for each transmission by the correction means, carrier detection can be performed early at the next or subsequent collision occurrence, and collision avoidance can be performed early.

  A first aspect of the present invention is a plurality of wireless transmission devices that perform carrier sense for collision prevention before transmission and perform transmission periodically, and the carrier sense unit of the wireless transmission device delays from reception input to carrier detection. A delay time setting means for recording time, an identification means for identifying a plurality of wireless transmission devices, a wireless control unit for performing collision detection and transmission / reception control of transmission signals, and according to the identification value of the identification means at every transmission By providing correction means for shifting the transmission timing back and forth by an integral multiple of the delay time of the delay time setting means, when a plurality of wireless transmission devices transmit at the same time within the delay time, other than the transmission timing of itself The radio control unit determines that there is a collision when the time until the carrier detection of the signal is equal to or less than the delay time of the delay time setting means + its own transmission time, Serial correcting unit, when a plurality of radio transmitting apparatus in the delay time is transmitted simultaneously transmits shifted an integer times time of the delay time at the time of the next transmission.

As a result, even if the receiving device cannot detect the carrier signal transmitted within the delay time, the wireless transmitting device receives the signal by transmitting at the timing exceeding the delay time from the first transmission timing at the next and subsequent transmissions. It becomes possible to recognize the transmission signal that the device has collided with, and the collision can be avoided at an early stage.

  A second invention is a plurality of wireless transmission devices that perform carrier sense for collision prevention before transmission and perform transmission periodically, and the carrier sense unit of the wireless transmission device delays from reception input to carrier detection. Delay time setting means for recording time, identification means for identifying a plurality of wireless transmission devices, a wireless control unit for performing collision detection and transmission / reception control of transmission signals, and timer or clock tolerance for managing time for periodic transmission By providing an error setting means for recording an error, and a correction means for correcting the transmission time for each transmission before and after an integral multiple of the allowable error of the error setting means according to the identification value of the identification means at the time of transmission, If there is a collision when the time from the transmission timing to the carrier detection of another signal is equal to or less than the delay time of the delay time setting means + its own transmission time Judgment by the control unit, and correction by the correction means from the ratio of the clock error between the radio transmission and transmission apparatus and the delay time, the transmission timing between the plurality of radio transmission devices than the delay time of the delay time setting means The collision avoidance can be avoided at the next transmission timing.

  In a third aspect of the invention, in particular, in the first or second aspect of the invention, the correction means uses the identification value of the identification means as a seed of random numbers, thereby transmitting a transmission time around an integer multiple of the generated random number. Correct every time.

  As a result, even when transmissions of a plurality of wireless transmission devices collide, even when the identification value cannot be known, the collision can be avoided with the minimum number of times.

  In a fourth aspect of the invention, in particular, in the first or second aspect of the invention, the error setting means includes a temperature correction means for setting a change rate of the timer or clock at the time of temperature change, so that the timer or clock at the time of temperature change is provided. A correction value is calculated based on the temperature change rate, and error correction is performed.

  Accordingly, even when there is a temperature change in the surrounding environment or a temperature change due to self-heating during transmission / reception, the accuracy of correction can be increased, and the time for avoiding a collision can be minimized.

  According to a fifth aspect of the present invention, there is provided a wireless communication system including a plurality of wireless transmission devices that perform carrier sense for collision prevention before transmission and perform periodic transmission and a reception device. A delay time setting unit that records a delay time from reception input to carrier detection, an identification unit that identifies a plurality of radio transmission devices, a radio control unit that performs collision detection and transmission / reception control of transmission signals, and transmission every hour A correction unit that shifts the transmission timing back and forth by an integral multiple of the delay time of the delay time setting unit according to the identification value of the identification unit, and a permission unit that permits correction of the correction unit from a wireless transmission device. The receiving device transmits a control command for avoiding a collision to a registration unit that records identification codes of a plurality of wireless communication devices that perform communication, and the wireless transmission device. A control command unit, wherein the permission unit detects a collision when the reception device cannot detect the periodic signals from a plurality of wireless transmission devices, and the control command of the reception device is detected. The unit transmits a collision avoidance control command by broadcast, and a plurality of wireless transmission devices permit correction by the correction means.

  As a result, collision avoidance can be performed at an early stage, correction operation for collision avoidance can be performed only when a collision occurs, reception time for standby in communication can be shortened, and power consumption of the entire system can be reduced. It can be reduced.

A sixth aspect of the present invention is a wireless communication system comprising a plurality of wireless transmission devices that perform carrier sense for collision prevention before transmission and perform periodic transmissions and a reception device, and the wireless transmission device includes carrier sense A delay time setting unit that records a delay time from reception input to carrier detection, an identification unit that identifies a plurality of radio transmission devices, a radio control unit that performs collision detection and transmission / reception control of transmission signals, and periodic transmission An error setting means for recording the time tolerance of the timer or clock, and a transmission time that is corrected before and after transmission by an integer multiple of the allowable error of the error setting means according to the identification value of the identification means at the time of transmission A wireless transmission device comprising: a correcting unit that performs correction; and a permission unit that permits correction of the correcting unit from a wireless transmission device, wherein the reception device performs communication of a plurality of units By providing a registration unit that records the identification code and a control command unit that transmits a control command for avoiding a collision to the wireless transmission device, the permission unit allows the reception device to receive periodic signals from a plurality of transmission devices. When the reception failure is detected, the wireless control unit detects a collision, transmits a collision avoidance control command by broadcast, and the correction unit permits the correction of an integer multiple of a timer or a clock by the error setting unit. Department permits.

  This makes it possible to minimize collision avoidance by recognizing timer or clock errors in the entire wireless communication system and reduce the standby reception time in communication, reducing power consumption in the entire system. Can do.

  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 1)
FIG. 1 shows a configuration diagram of a radio transmission apparatus according to Embodiment 1 of the present invention.

  In FIG. 1, in this example, an antenna 101 for transmitting / receiving a signal to / from the wireless transmission device 100-1, an antenna control unit 102 for switching between transmission and reception, a wireless control unit 105 for performing signal control, and a transmission filter circuit. A basic configuration includes a transmission unit 103 and a reception unit 104 that is a reception filter unit.

  The wireless control unit 105 includes an identification unit 108 that records the identification code of the wireless transmission device 100-1, a carrier sense unit 107 that performs carrier detection of a received signal, and a detection that is performed by the carrier sense unit 107 after being received by the antenna 101. Delay time setting means 106 for setting a delay time until the start time, a random number generator 1091 for generating a random number from the delay time value and the value of the identification means 107, and a correction means 109 for correcting the transmission timing by the random number. It consists of the following.

  FIG. 2 shows that when (a) two wireless transmission apparatuses 100-1 and 100-2 transmit, carrier sense is performed and transmission is stopped when carrier detection is performed at a timing when carrier detection is possible. In this example, transmission is performed at different times.

  When (b) is transmitted by the two wireless transmission devices 100-1 and 100-2, carrier sense is performed, and carrier detection is not possible, and carrier signals cannot be detected, so transmission signals collide. An example is shown.

  When (c) is transmitted by the two wireless transmission devices 100-1 and 100-2, carrier sense is performed, and even when a timing at which carrier detection is impossible occurs, the collision is detected by the correction means in the next transmission. An example to avoid is shown.

  Next, the operation and action of the wireless transmission device 100-1 having such a configuration will be described.

First, the radio control unit 105 generates a signal to be transmitted at regular intervals, sends the signal to the transmission unit 103 that is a transmission filter, controls the antenna control unit 102, switches to the transmission unit 103, and switches to the antenna 101. The signal is transmitted wirelessly.

  The wireless control unit 105 holds the individual identification data of the wireless transmission device 100-1 in the identification unit 108, and transmits the data included in the generated transmission data.

  In addition, the radio control unit 105 performs carrier detection by the carrier sense unit 107 at the time of transmission at regular intervals, and stops transmission when a signal is present in the transmission frequency band, and retransmits after a certain time has elapsed. To do.

  Also, the radio control unit 105 presets in the delay time setting means 106 a delay time from when a signal is input to the antenna 101 until it is detected by the carrier sense unit 107, and is corrected at the time of transmission at regular intervals. The means 109 transmits the data by shifting the timing of an integral multiple of the delay time. Further, the correction means 109 determines the timing for shifting from the value randomly generated by the random number generation unit 1091 based on the identification value of the identification means 108 at the time of transmission at regular intervals.

  As shown in FIG. 2A, the wireless transmission device 100-1 performs carrier sense in the carrier sense unit 107 before transmission, and transmits because there is no carrier. Thereafter, transmission is performed at a constant interval t2. Similarly, the other wireless transmission device 100-2 performs transmission at an interval of t2 ′, and t2 = t2 ′. However, a minute difference occurs due to an allowable error of a built-in timer. For example, when t2 = t2 ′ is 1 second and the tolerance is 20 ppm, the difference of 20 μs is shifted every cycle.

  In order to detect the carrier signal 1A before transmission at the timing when the wireless transmission device 100-1 transmits and then the wireless transmission device 100-2 transmits at point A after elapse of t3-1, Further, the wireless transmission device 100-2 performs transmission at point A ′ after elapse of t4. Thus, when carrier detection can be performed by the carrier sense unit 107, collision of transmission signals can be avoided.

  Next, the timing at which a collision cannot be avoided as shown in FIG.

  Due to an error in the built-in timers of the wireless transmission devices 100-1 and 100-2, the transmission interval between the wireless transmission devices 100-1 and 100-2 is narrowed during continuous periodic transmission, from reception input to carrier detection. The transmission of the wireless transmission signal 100-2 occurs within the delay time t1 (t3-2), and the transmissions of the wireless transmission devices 100-1 and 100-2 collide. In this case, after that, transmission at a constant interval is continuously repeated until the transmission becomes possible with a time difference equal to or longer than the delay time t1 due to a timer error.

  For example, if the timer error is 20 ppm and the delay time t1 is 300 μs, the error of 20 μs is shifted every transmission, and the collision continues 15 times and is avoided the 16th time. If the error of the timer is 1 ppm, the collision will be repeated 300 times, and the time during which transmission cannot be performed normally will be continued for a long time.

  Next, as shown in FIG. 2 (c), the timing for avoiding with the minimum number of times after the collision by the correcting means is shown.

Due to an error in the built-in timers of the wireless transmission devices 100-1 and 100-2, the transmission interval between the wireless transmission devices 100-1 and 100-2 is narrowed during continuous periodic transmission, from reception input to carrier detection. The transmission of the wireless transmission signal 100-2 occurs within the delay time t1 (t3-2), and the transmissions of the wireless transmission devices 100-1 and 100-2 collide. In this case, the time (t3-2 + t1) from when each of the wireless transmission devices 100-1 and 100-2 senses the other wireless transmission signal received by the carrier sensing unit 107 is the own transmission time + delay. The radio control unit 105 determines that a collision has occurred when the time is shorter than the time t1, and the radio transmission device 100-1 corrects the next transmission timing by the correction unit 109 after t2-t1 time, and the radio control unit 105 issues a transmission command.

  In this example, when the identification value of the identification unit 108 is 1 and the coefficient of the random number generator 1091 is 1, the time of the delay time t1 is corrected. However, even if the value is changed, the correction is similarly performed. It is possible to do.

  The wireless transmission device 100-2 can detect the transmission signal of the wireless transmission device 100-1 at the timing of the carrier signal 1B, and the wireless transmission device 100-2 can transmit the signal shifted by t4 time.

  Thereafter, transmission is continuously performed at time intervals t2 and t2 ′. When a collision occurs again, the same collision avoidance operation is performed.

  As described above, in the present embodiment, the carrier sense unit of the wireless transmission device records the delay time from reception input to carrier detection, and the identification means for identifying a plurality of wireless transmission devices. A plurality of wireless transmission devices within the delay time by providing correction means for shifting the transmission timing back and forth by an integral multiple of the delay time of the delay time setting means according to the identification value of the identification means at every transmission Are simultaneously transmitted, the radio control unit determines that there is a collision when the time from its own transmission timing to the detection of another signal carrier is equal to or less than the delay time of the delay time setting means + the own transmission time. Then, when a plurality of wireless transmission devices transmit at the same time within the delay time, the correction means transmits the time shifted by an integral multiple of the delay time at the next transmission. , It is possible to avoid the collision avoidance at an early stage.

  Even when there are a plurality of wireless transmission devices, the number of wireless transmission devices can be changed by changing the transmission timing when transmission time + delay time> time from transmission start to carrier detection. Collision avoidance is possible regardless of

  Also, here, an example is shown in which a collision is avoided from the condition of transmission time + delay time. However, even if a case where the carrier cannot be detected for the other signal due to the collision occurs as a determination condition. Similarly, collision avoidance is possible.

(Embodiment 2)
FIG. 3 shows a configuration diagram of a radio transmission apparatus according to the second embodiment of the present invention.

  In FIG. 3, the error setting means 110 records the allowable error of the internal clock of the wireless transmission device 100B-1 and the allowable error of the internal clock of another wireless transmission device, and the wireless transmission device in the system performing communication. To grasp the error of the internal clock. Further, temperature correction means 1101 for correcting an error due to the temperature of the internal clock is provided in the error setting means 110. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

  Next, the operation and action of the radio transmission apparatus having such a configuration will be described.

The error setting means 110 has different timer and clock tolerances held in the radio control unit 105 for each radio transmitting apparatus 100B-1. For this reason, the transmission timing at regular intervals also includes an error, and there is a difference for each wireless transmission device 100B-1. Accordingly, transmission signal collisions periodically occur as the transmission timing interval changes due to the difference in allowable error for each wireless transmission device 100B-1.

  For example, if the difference in allowable error is 10 ppm, a difference occurs by 10 μs for each transmission in the case of transmission timing at intervals of 1 second. Once generated, if the delay time is 300 μs, carrier detection cannot be performed for 30 seconds.

  The error setting means 110 sets the allowable error change rate and the timer or clock allowable error of another wireless transmission device in advance from the allowable error of the timer or clock of the wireless transmission device 100B-1 itself and the ambient temperature. The temperature correction unit 1101 measures the ambient temperature and corrects the allowable error of the error setting unit 110 from the change rate.

  Next, when a radio transmission signal collision is detected by the radio control unit 105, the allowable error of the colliding partner and its own allowable error are determined from the value of the error setting means 110, and the correction means is determined from the difference between the allowable errors. In 109, a correction value to be corrected is calculated, and the transmission timing is corrected.

  Since other operations and functions are the same as those in the first embodiment, the description thereof will be omitted.

  As described above, in the present embodiment, the error setting unit 110 sets and holds its own allowable error, temperature change rate, and communication partner allowable error, so that when the difference between the allowable errors is small, the correction unit The transmission timing correction time at 109 is increased and the transmission is shifted, and the optimum correction can be performed by recognizing the difference in the allowable error, and collision can be avoided at an early stage.

  Also, by correcting the change due to the ambient temperature from the temperature change rate of the timer or clock tolerance by the temperature correction means 1101, accurate correction is possible even when the ambient temperature at the installation location or the temperature change due to self-heating due to transmission / reception occurs. The means 109 can be corrected.

  Here, it is assumed that the allowable error of the communication partner of the error setting unit 110 is set and held, but the method of transmitting and receiving the allowable error data of the partner during communication and setting the value in the error setting unit 110 But it is possible. Also, the rate of change of the allowable error due to the change in the ambient temperature of the other party can be set during communication.

(Embodiment 3)
FIG. 4 shows a configuration diagram of the radio communication system according to the third embodiment of the present invention, and FIG. 5 shows transmission / reception timings of the radio communication system.

  In FIG. 4, a communication system having a plurality of wireless transmission / reception devices is configured. In the wireless transmission / reception new devices 200-1 to 200-4, the registration unit 111 registers the identification value held in the communication partner identification unit 108 at the time of reception at the time of reception. The control command unit 112 transmits a control command for notifying that the radio control unit 105 is colliding with the other radio transmission / reception devices 200-2 to 200-4 when the transmission signal collision is detected.

  Next, the permission unit 113 permits the correction of the correction unit 109 to avoid collision only when the wireless transmission / reception devices 200-2 to 4-4 that have received the control command from the control command unit 112 have received the control command. Consists of what to do. Since other configurations are the same as those of radio transmission apparatus 100-1 of the first embodiment, description thereof is omitted.

In FIG. 5, the transmission / reception device 200-1 transmission signal indicates the transmission signal timing of the wireless transmission / reception device 200-1, and the wireless transmission / reception device 200-1 reception carrier sense indicates the carrier sense timing of the wireless transmission / reception device 200-1. . Similarly, the transmission signal and reception carrier sense timing of the wireless transmission / reception apparatus 200-2 are shown.

  The wireless transmission / reception device 200-4 transmission signal (broadcast) indicates the timing of transmitting the command signal from the control command unit 112, and the wireless transmission / reception device 200-4 reception carrier sense indicates the carrier sense timing of the wireless transmission / reception device 100-3. Show.

  Next, the operation and action of the radio transmission apparatus having such a configuration will be described.

  When each of the wireless transmission / reception devices 200-1 to 200-4 performs periodic transmission at the same time interval, the wireless transmission / reception device 200-1 transmits first, the wireless transmission / reception device 200-2 transmits after a certain time, and further wireless The transmission / reception device 200-3 and the wireless transmission / reception device 200-4 sequentially transmit at intervals. In this state, each of the wireless transmission / reception apparatuses 200-1 to 200-4 continuously performs transmission at the same interval time.

  Each of the wireless transmission / reception devices 200-1 to 200-4 receives a signal transmitted during wireless communication, and registers the identification value set in the transmission source identification unit 108 in its own registration unit 111. For example, the wireless transmission / reception device 200-1 performs transmission, and the received wireless transmission / reception devices 200-2 to 200-4 register the identification values of the wireless transmission / reception device 200-1 in the respective registration units 111. Then, since each identification value is registered, the identification value of all the radio | wireless transmission / reception apparatuses which exist in a radio | wireless communications system is registered into the registration part 111. FIG.

  The timers or clocks of the respective radio transmission / reception devices 200-1 to 200-4 have an error, so that the transmission interval gradually shifts. For example, the transmission of the radio transmission / reception device 200-2 transmits the transmission signal of the radio transmission / reception device 200-1. When a state of transmitting itself occurs within a delay time (t1 in FIG. 5) from reception until carrier detection of the carrier sense unit 107 (carrier signal 1A in FIG. 5) (point B in FIG. 5), The wireless transmission / reception devices 200-1 and 2 are in a state where transmission signals collide, and the other wireless transmission / reception devices 200-3 and 4 cannot accurately receive the signals of the wireless transmission / reception devices 200-1 and 2 (FIG. 5). Carrier signal 2A).

  At this time, it is impossible for the carrier sense unit 107 to perform carrier detection for transmission at regular intervals, and the radio control unit 105 indicates that the radio transmission / reception apparatuses 200-1 and 2 having the identification value registered in the registration unit 111 cannot communicate. The control command unit 112 issues a command to the wireless control unit 105 to notify the wireless control devices 200-1 and 2 other than itself by a broadcast signal. (Broadcast 3A in FIG. 5) The wireless transmission / reception devices 200-1 and 2 that have received the notification command (carrier signal 4A, carrier signal 3A in FIG. 5) have their transmission timing corrected by means 109, and delay time setting means Transmission is performed by shifting an integral multiple of the delay time set in 106.

  Since there is a time difference shifted by the identification value by the random number generator 1091, collision is avoided. Also, the direction of shifting can be either forward or backward, and can be determined by the random number generator 1091.

As described above, in the present embodiment, the identification values of all of the wireless transmission / reception devices 200-1 to 200-4 existing in the wireless communication system are registered in the registration unit 111 during normal communication, and each wireless transmission / reception device 200- When it is detected that reception of the periodic transmission signals 1 to 4 is disabled at the time of reception, the wireless control unit 105 determines that a transmission signal collision has occurred, and the control command unit 112 notifies the collision. Notification is made to each of the wireless transmission / reception devices 200-1 to 200-4. The wireless transmitter / receiver that has received the notification changes the transmission timing to transmit, so that the entire wireless communication system can immediately avoid a collision, and the timing can be shifted only at the next transmission at the time of the collision. Since transmission is performed, the current consumption by transmission and the reception standby time after transmission are made longer than the normal reception timing only at the time of broadcast reception, whereby the reception current consumption can be minimized.

(Embodiment 4)
FIG. 6 shows a configuration diagram of a radio communication system according to the fourth embodiment of the present invention.

  In FIG. 6, a communication system having a plurality of wireless transmission / reception devices is configured. In the wireless transmission / reception apparatuses 300-1 to 300-4, the registration unit 111 registers the identification value held in the communication partner identification unit 108 at the time of reception at the time of reception. The control command unit 112 transmits a control command for notifying that the radio control unit 105 is colliding with the other radio transmission / reception devices 200-2 to 200-4 when the transmission signal collision is detected.

  Next, the permission unit 113 permits the correction of the correction unit 109 to avoid collision only when the wireless transmission / reception devices 200-2 to 4-4 that have received the control command from the control command unit 112 have received the control command. Consists of what to do. Since other configurations are the same as those of radio transmission apparatus 100B-1 of the second embodiment, description thereof is omitted.

  Next, the operation and action of the radio transmission apparatus having such a configuration will be described.

  When each of the wireless transmission / reception devices 300-1 to 300-4 performs periodic transmission at the same time interval, the wireless transmission / reception device 300-1 transmits first, the wireless transmission / reception device 300-2 transmits after a predetermined time, and further wireless The transmission / reception device 300-3 and the wireless transmission / reception device 300-4 sequentially transmit at intervals. In this state, each of the wireless transmission / reception apparatuses 300-1 to 300-4 continuously performs transmission at the same interval time.

  Each of the wireless transmission / reception apparatuses 300-1 to 4 receives a signal transmitted during wireless communication, and registers the identification value set in the transmission source identification unit 108 in its own registration unit 111. For example, the wireless transmission / reception device 300-1 performs transmission, and the received wireless transmission / reception devices 300-2 to 300-4 register the identification values of the wireless transmission / reception device 300-1 in the respective registration units 111.

  Then, since each identification value is registered, the identification value of all the radio | wireless transmission / reception apparatuses which exist in a radio | wireless communications system is registered into the registration part 111. FIG.

  The timers or clocks of the respective radio transmission / reception devices 300-1 to 300-4 are gradually shifted due to an error. For example, the transmission of the radio transmission / reception device 300-2 transmits the transmission signal of the radio transmission / reception device 300-1. When a state in which the transmission is performed within a delay time from reception until carrier detection of the carrier sense unit 107 occurs, the wireless transmission / reception apparatuses 300-1 and 2 are in a situation where transmission signals collide with each other. The wireless transmission / reception devices 300-3 and 4 cannot correctly receive the signals of the wireless transmission / reception devices 300-1 and 300-2.

  At that time, the carrier detection unit 107 cannot perform carrier detection at a constant interval transmission, and the radio control unit 105 indicates that the radio transmission / reception apparatuses 300-1 and 2 having the identification value registered in the registration unit 111 cannot communicate. The control command unit 112 issues a command to the wireless control unit 105 to notify the wireless control devices 300-1 and 2 other than itself by a broadcast signal. The wireless transmission / reception apparatuses 300-1 and 2 that have received the notification command perform transmission by shifting their own transmission timing by the correction unit 109 by an amount that is an integral multiple of the delay time set in the delay time setting unit 106. .

The error setting means 110 sets the allowable error change rate and the timer or clock allowable error of another wireless transmission device in advance from the allowable error of the timer or clock of the wireless transmission device 100B-1 itself and the ambient temperature. The temperature correction unit 1101 measures the ambient temperature and corrects the allowable error of the error setting unit 110 from the change rate. Further, the direction of shifting can be either forward or backward, and can be determined by the correction means 109.

  As described above, in the present embodiment, the identification values of all of the wireless transmission / reception devices 300-1 to 300-4 existing in the wireless communication system are registered in the registration unit 111 during normal communication, and each wireless transmission / reception device 300- When it is detected that reception of the periodic transmission signals 1 to 4 is disabled at the time of reception, the wireless control unit 105 determines that a transmission signal collision has occurred, and the control command unit 112 notifies the collision. Notification is made to each of the wireless transmission / reception devices 300-1 to 300-4. In the wireless transmission / reception apparatus that has received the notification, the temperature correction unit 1101 measures the ambient temperature, the allowable error setting unit 110 performs temperature correction based on the allowable error change rate, and performs transmission by changing the transmission timing according to the correction. As a result, the entire wireless communication system can immediately avoid a collision, and broadcast transmission that shifts the timing only at the next transmission at the time of the collision occurs, so the current consumption by transmission and the reception waiting time after transmission The current consumption during reception can be minimized by making the time longer than the normal reception timing only during broadcast reception.

  Note that the means described in this embodiment causes hardware resources such as a CPU (or microcomputer), a RAM, a ROM, a storage / recording device, an electrical / information device including an I / O, a computer, a server, and the like to cooperate. You may implement with the form of a program. In the form of a program, new functions can be easily distributed / updated and installed by recording them on a recording medium such as magnetic media or optical media or distributing them via a communication line such as the Internet.

  In this embodiment, the wireless transmission device 100-1 is described as a transmission device. However, the present invention is not limited to this, and a wireless reception device, a mobile phone, a portable music player, a portable personal computer, a portable information terminal, an IC card, It is also effective to mount on a key.

  As described above, according to the present invention, in a system in which wireless communication is continuously performed, a plurality of transmission apparatuses are equipped with a carrier detection function and cannot be detected due to a delay time on hardware, so that collision occurs and reception cannot be performed accurately. Even in this case, continuous collision can be prevented by shifting collision detection and transmission timing.

  This is not only for general home appliances, but also for maintaining the security that requires urgency while improving the convenience of people who use it everyday in the position detection and function restrictions of communication devices and mobile phones, etc. It can also be applied to operations of industrial machines and equipment such as buildings and factories, and authentication systems.

Configuration diagram of radio transmitting apparatus according to Embodiment 1 of the present invention Transmission timing diagram of radio transmitting apparatus according to Embodiment 1 of the present invention Configuration diagram of radio transmitting apparatus according to embodiment 2 of the present invention Configuration diagram of a wireless communication system according to a third embodiment of the present invention Transmission timing diagram of radio transmission apparatus according to embodiment 3 of the present invention Configuration diagram of a wireless communication system according to a third embodiment of the present invention Configuration diagram of a conventional wireless communication system

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Central control station 12-A, 12-B Radio | wireless telephone 13-A-13-F Data terminal 100-1, 100B-1 Wireless transmission apparatus 101 Antenna 102 Antenna control part 103 Transmission part 104 Reception part 105 Wireless control part 106 Delay time setting unit 107 Carrier sense unit 108 Identification unit 109 Correction unit 110 Error setting unit 111 Registration unit 112 Control command unit 113 Authorization unit 1091 Random number generation unit 1101 Temperature correction unit 200-1 to 4, 300-1 to 4

Claims (5)

A plurality of wireless transmission devices that perform carrier sense for collision prevention before transmission and perform periodic transmission,
A carrier sense unit of a wireless transmission device records delay time from reception input to carrier detection, identification means for identifying a plurality of wireless transmission devices, and wireless for performing transmission signal collision detection and transmission / reception control A control unit, and a correction unit that shifts the transmission timing back and forth by an integral multiple of the delay time of the delay time setting unit according to the identification value of the identification unit at every transmission,
In the case where a plurality of wireless transmission devices transmit simultaneously within the delay time, the correction means determines that the wireless control unit has collided, and transmits the data by shifting an integral multiple of the delay time during the next transmission. A wireless transmission device that avoids collision with a minimum number of subsequent periodic transmissions. A plurality of wireless transmission devices that perform carrier sense for collision prevention before transmission and perform periodic transmission,
A carrier sense unit of a wireless transmission device records delay time from reception input to carrier detection, identification means for identifying a plurality of wireless transmission devices, and wireless for performing transmission signal collision detection and transmission / reception control A control unit, an error setting means for recording a timer or clock allowable error for periodical transmission time management, and transmission before and after an integer multiple of the allowable error of the error setting means according to the identification value of the identification means at the time of transmission With correction means for correcting the time for each transmission,
The radio control unit determines a collision, and the error setting unit corrects a time that is an integer multiple of a timer or a clock by the correction unit, so that the transmission timing between the plurality of radio transmission apparatuses is the transmission signal. A wireless transmission apparatus for avoiding a collision by being longer than the delay time of the delay time setting means. 3. The radio transmission apparatus according to claim 1, wherein the correction means uses the identification value of the identification means as a seed of random numbers, and corrects the transmission time for each transmission before and after an integer multiple of the generated random numbers. A temperature correction means for setting a change rate of a timer or a clock at the time of temperature change is provided in the error setting means, and the set value set by the error setting means at the time of temperature change is corrected to enable early collision avoidance. The wireless transmission device of either 1 or 2. A wireless communication system comprising a plurality of wireless transmission devices that perform carrier sense for collision prevention before transmission and periodically transmit, and a reception device,
The wireless transmission device performs delay time setting means for recording a delay time from reception input to carrier detection by a carrier sense unit, identification means for identifying a plurality of wireless transmission devices, and collision detection and transmission / reception control of transmission signals A wireless control unit, a correction unit that shifts the transmission timing back and forth by an integral multiple of the delay time of the delay time setting unit according to the identification value of the identification unit at every transmission, and the correction of the correction unit from the wireless transmission device A receiving unit that records the identification codes of the wireless transmission devices that are communicating with each other, and a control that transmits a control command for avoiding a collision to the wireless transmission device With a command section,
The permission unit is configured to detect a collision when the reception device cannot detect periodic signals from a plurality of wireless transmission devices, and the control command unit of the reception device broadcasts the collision avoidance control command. A wireless communication system for avoiding a collision by allowing a plurality of wireless transmission devices to permit correction by the correction means.

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