Communication system and communication method in a communication system

Abstract

To provide a communication system that can perform communication without data loss, thereby saving power.SOLUTION: A communication system comprises: a receiving device that is provided with single unit receiving processing execution means and single day receiving processing execution means; and a plurality of transmission devices that transmits data at an interval of T seconds. When the single unit receiving processing execution means performs receiving processing for the duration of T×a seconds, while the plurality of transmission devices transmits data for the duration of T×a seconds, the time for a data waiting period and the time for a pause period are determined according to the probability of data that can be received by the receiving device to all of transmitted data, and these times are set.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] This invention relates to a communication system and a communication method in the communication system.

Background Art

[0002] For example, a communication system using IoT (Internet of Things) is usually battery-driven by a dry battery or the like. Therefore, except when actually communicating, it is in a sleep state, reducing power consumption.

[0003] However, in a system where a plurality of transmission devices and one reception device perform data communication, if these transmission devices and reception devices randomly enter the sleep state, a situation may occur where the transmitted data is not received, and it cannot be made appropriate. Therefore, a system that can communicate without data loss while being power-saving is required.

[0004] Also, regarding maintenance related to power sources such as battery replacement, it is usually randomly performed on a plurality of transmission devices and one reception device, and there is a problem that the maintenance time and cost are increasing.

[0005] Patent Document 1 discloses a power-saving processing method. By this power-saving processing method, in a master communication terminal that simultaneously establishes a plurality of communication links with a plurality of slave communication terminals, the transition time is reduced and the power-saving operation time is lengthened.

[0006] In this power-saving processing method, when power-saving operation is performed on multiple slave communication terminals that have established asynchronous communication links with a master communication terminal, the master communication terminal sets the communication cycle of all communication links to be the same and sets the communication start time and communication duration of each communication link so that each communication slot used for the communication link is within a continuous range. The master communication terminal performs negotiation with the multiple slave communication terminals according to the settings. Then, the master communication terminal performs its own power-saving operation during the period of unused slots that are grouped together as a single range by the above settings.

[0007] Furthermore, Patent Document 2 discloses a wireless communication device and wireless communication system that have low power consumption. This invention is a wireless communication system that includes a master unit and a slave unit and forms a multi-hop network. The wireless communication device operates as either a master unit or a slave unit, and when data transmission and reception are completed, it enters a sleep state, and when no data is being transmitted, it determines whether to temporarily release the sleep state and re-enter the sleep state at regular intervals. The device includes a relay table management unit which registers the number of hops to the master unit and the number of subordinate wireless communication devices that communicate with the master unit via itself, and an intermittent period determination unit which determines an intermittent period of a certain time based on the number of hops and the number of subordinate devices.

[0008] Furthermore, Patent Document 3 discloses an invention for reducing the cost of replacing batteries in wireless terminals. The wireless control device of this invention selects a first wireless terminal with a short remaining battery life based on the battery information of each wireless terminal, and if the first wireless terminal is selected, it selects a second wireless terminal with a long remaining battery life, and instructs the wireless base station, the first and second wireless terminals to change the communication path between the first wireless terminal and the wireless base station to a communication path that communicates between the first wireless terminal and the wireless base station via the second wireless terminal, and to connect the first and second wireless terminals using the second communication function.

[0009] The first wireless terminal transmits uplink data to the second wireless terminal using the second communication function, and the second wireless terminal transmits the uplink data to the wireless base station using the first communication function. The second wireless terminal receives downlink data to be transmitted to the first wireless terminal from the wireless base station using the first communication function, and transmits the downlink data to the first wireless terminal using the second communication function. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] Japanese Patent Publication No. 2004-152268 [Patent Document 2] Japanese Patent Publication No. 2014-183470 [Patent Document 3] Japanese Patent Publication No. 2020-145532 [Overview of the project] [Problems that the invention aims to solve]

[0011] As mentioned above, while inventions have been made from the perspective of power saving, we have not yet reached the point of providing a communication system that offers improvements in two directions: enabling communication without data loss while also saving power.

[0012] The objective of the embodiments of the present invention is to provide a communication system that enables communication without data loss while also being power-efficient. [Means for solving the problem]

[0013] The communication system according to this embodiment includes a receiving device comprising: When the plurality of transmitting devices transmit data over a period of T × a seconds, and the receiving process by the 1-unit receiving processing execution means is performed for T × a seconds, the data waiting period and the pause period are determined and set according to the probability that the data that can be received by the receiving device is relative to all transmitted data.

[0014] In the communication system according to this embodiment, the receiving device and the plurality of transmitting devices are powered by a battery, and the number of times the data waiting period is determined is determined so that the operating times of the receiving device and the plurality of transmitting devices powered by the battery are the same, and the interval of the transmitting devices is determined.

[0015] The communication method in the communication system according to this embodiment is a communication method in a communication system comprising: a receiving device having a receiving device having a receiving processing execution means that executes a receiving processing that consists of a receiving processing period which is a combination of a data waiting period in an operational state and a resting period in an inactive state, and a receiving processing period which is repeated n times to form one unit receiving processing period; a receiving device having a receiving processing execution means that executes the one unit receiving processing period which is repeated m times in one day; and a plurality of transmitting devices having a data transmission interval of T seconds, wherein When the plurality of transmitting devices transmit data over a period of T × a seconds, and the receiving process by the one-unit receiving processing execution means is performed for T × a seconds, the data waiting period and the pause period are determined according to the probability of the data that can be received by the receiving device relative to all transmitted data, and communication is performed after setting these periods.

[0016] In the communication system according to this embodiment, the receiving device and the plurality of transmitting devices are powered by batteries, and the number of times the data waiting period is determined and the interval of the transmitting devices is determined so that the operating times of the receiving device and the plurality of transmitting devices powered by the batteries are the same, and communication is performed using these determined parameters. [Brief explanation of the drawing]

[0017] [Figure 1] Configuration diagram of a communication system according to an embodiment of the present invention. [Figure 2] Configuration diagram of a transmission device used in a communication system according to an embodiment of the present invention. [Figure 3] Configuration diagram of a reception device used in a communication system according to an embodiment of the present invention. [Figure 4] Timing chart showing the operation of a transmission device used in a communication system according to an embodiment of the present invention. [Figure 5] Timing chart showing the operation of a reception device used in a communication system according to an embodiment of the present invention. [Figure 6] Timing chart showing the operation of a reception device used in a communication system according to an embodiment of the present invention. [Figure 7] Diagram showing the probability of receiving data sent from a transmission device in the case of reception by the reception method of a reception device used in a communication system according to an embodiment of the present invention. [Figure 8] Diagram having, on the horizontal axis, the interval of the transmission device and the time obtained by multiplying the number of repetitions (X2=n) in one reception processing period by the data waiting period (C8) of the reception device, corresponding to the operating times of the reception device and the transmission device used in a communication system according to an embodiment of the present invention.

Mode for Carrying Out the Invention

[0018] Hereinafter, a communication system according to an embodiment of the present invention and a communication method in the communication system will be described with reference to the accompanying drawings. The same reference numerals are given to the same components in each figure, and redundant descriptions are omitted. The communication system according to the embodiment of the present invention can adopt, for example, a configuration as shown in FIG. 1. That is, it includes a plurality of transmission devices S and a repeater C that receives data from these transmission devices S.

[0019] The repeater C shown here has the functions of a receiving device R that receives data from a transmitting device S, and a transmitting device S that transmits the received data to another repeater C or gateway GW. The gateway GW is connected to repeater C and also to the cloud CL.

[0020] Communication between repeater C and between repeater C and gateway GW is conducted using, for example, LPWA (LOW POWER WIDE AREA) network technology, and communication between repeater C and transmitter S is conducted using, for example, Bluetooth® technology. Both repeater C and transmitter S are powered by batteries. In this specification, batteries include both rechargeable and non-rechargeable batteries.

[0021] As described above, the repeater C has the functions of both a receiving device R and a transmitting device S, but in this embodiment, we will describe it as having the function of only the receiving device R. The multiple transmitting devices S have the configuration shown in Figure 2.

[0022] In other words, the transmitting device S includes a central control unit 100, which is composed of a CPU and main memory, etc., which are the core components of a computer. A sensor 101 for acquiring data is connected to the central control unit 100, as well as a display device 102 and an input device 103. The display device 102 is used to display necessary information, and the input device 103 is used to input necessary commands and data.

[0023] A communication control unit 104 is connected to the central control unit 100, and a wireless transceiver unit 105 is connected to the communication control unit 104. Data acquired from the sensor 101 is sent from the central control unit 100 to the communication control unit 104 for transmission, where it is converted into data in the required format and sent to the wireless transceiver unit 105. The wireless transceiver unit 105 converts the received data into a wireless signal in a predetermined format for transmission and transmits it.

[0024] The receiving device R of this embodiment is configured as shown in Figure 3. The receiving device R receives the signal sent from the transmitting device S as described above using the wireless transceiver unit 201 and converts it into a baseband signal. The received and basebandized signal is sent to the communication control unit 202, where it is converted into data in a format usable within the receiving device R and then sent to the central control unit 200.

[0025] The central control unit 200 is connected to a display device 203 and an external transmission interface 204. The central control unit 200 can send received data to the display device 203 for display in a predetermined format, and can also send received data to the transmitting device S via the external transmission interface 204 for transmission to the next repeater C, gateway GW, etc. Furthermore, an input device 205 is connected to the central control unit 200, and necessary commands and data can be input from the input device 205.

[0026] In the communication system according to this embodiment, the transmitting device S is designed with power saving in mind. Figure 4 As shown, the data transmission interval is T seconds, and the transmission processing period, which is the period during which data transmission is performed while the power is ON and the system is operational, is Figure 4 As shown, the interval T seconds and the transmission processing period (time) are input from the input device 103 and set in the central control unit 100.

[0027] In the communication system according to this embodiment, the receiving device R, from the viewpoint of power saving, is equipped with a one-unit receiving processing execution means 211 (Figure 3) that performs receiving processing by repeating a receiving processing period consisting of a data waiting period in an operational state and a rest period in an inactive state n times, to form one unit receiving processing period, as shown in Figure 5. Furthermore, the receiving device R is equipped with a one-day receiving processing execution means 212 that repeats the above one-unit receiving processing period m times per day. Figure 6 The various parameters used by the 1-unit receiving processing execution means 211 and the 1-day receiving processing execution means 212 can be input from the input device 205.

[0028] If the data waiting period for the receiving device R is 100 milliseconds and the pause period is 500 milliseconds, then the reception processing period is 600 milliseconds Therefore, when the interval T is 2 seconds, and T is repeated 3 times (2 × 3 = 6), the reception processing period can be repeated 10 times. When the reception processing by the 1-unit reception processing period execution means 211 is performed for 6 (T × a) seconds, the probability of the data that can be received by the reception device R relative to all transmitted data is calculated.

[0029] As shown in Figure 7, each 100 millisecond interval is represented by one section, the data waiting period is shown as upward-sloping hatching, the pause period is shown in white, and if one horizontal row represents 2 seconds, then 6 seconds can be represented by 3 rows. In other words, in Figure 7, if 100 milliseconds of reception are performed once every 600 milliseconds, with 2 seconds as one unit, the total number of times that can be received is the number of sections with upward-sloping hatching. In this example, as shown in the "Total" column, out of 20 sections 10 sections It is receivable in and among the data from multiple transmitting devices S 50% It has been shown that reception is possible with a certain probability. In this embodiment, the above parameters are set so that this probability is a desired value. When this probability is 100%, communication is possible without any data loss, but the probability is set to a desired value due to system design considerations. Therefore, the above A probability of 50% or more, as shown above, can be considered preferable.

[0030] As mentioned above, this embodiment is equipped with a configuration for saving power, but we will consider further power saving. (1) The operating time of one transmitter S can be determined from the battery capacity (C1) of the transmitter S. Operating time (days) = C1 / daily current consumption (Equation 1) The daily current consumption of a single transmitter S is the sum of a fixed daily standby current (C2) and the increase due to transmission. Daily current consumption = C2 + [Transmit current / day] (Equation 2) The transmission current of a single transmitter S is the amount obtained by multiplying the amount of current consumed in one transmission (C3) by the number of transmissions per day. [Transmit current / day] = C3 × [Number of transmissions / day] (Equation 3) The number of transmissions can be calculated from the time in a day (C4) and the transmission interval (X1) as follows. [Number of transmissions / day] = C4 / X1 (Equation 4) According to Equations 1 to 4 Operating hours (days) = C1 / (C2+(C3×(C4 / X1))) (Equation 5) Equation 5 shows that the larger X1, the longer the operating time. The transmission interval (X1) is simply the interval in T seconds.

[0031] (2) On the other hand, the operating time of the receiving device R can be determined from the battery capacity (C5) of the receiving device R. Operating time (days) = C5 / daily current consumption (Equation 6) The receiving device R consumes power at a fixed rate. Amount of current In addition to (C6), it is consumed when the system is operational for receiving data. Amount of current It will be added. Daily current consumption = C6 + [reception during operation] Amount of current / day] (formula 7) The receiving device R receives data at a period independent of the multiple transmitting devices S, and performs one unit of receiving processing time a fixed number of times (C7=m) per day. As previously described, one unit of receiving processing time is achieved by repeating a data waiting period (C8), in which the device is operational and waiting for incoming data, (X2=n) times. Therefore, if C9 is the amount of current consumed per unit time during one data waiting period, then the [data reception current / day] is as follows: [Data reception] Amount of current / day]=C7×(C8×X2× C9 ) (Formula 8) According to equations 6 to 8 Operating hours (days) = C5 / (C6 + (C7 × (C8 × X2 × C9 ))) (Formula 9) Equation 9 shows that the smaller X2 is, the longer the operating time.

[0032] Therefore, it is necessary that equation (5) and equation (9) are equal. In this case, C1, C2, and C4 in equation (5) are fixed values, and C5, C6, and C7 in equation (9) are fixed values. Thus, In the transmitting device Interval time T With this as the horizontal axis, the receiving device The horizontal axis represents the time obtained by multiplying the data waiting period (C8) by the number of repetitions in one unit of reception processing (X2=n). Both the transmitting and receiving devices The point (time) where the curves with operating time on the vertical axis intersect, as shown in Figure 8, represents the optimal operating time.

[0033] In this embodiment, the receiving device R and the plurality of transmitting devices S are powered by batteries. Therefore, the number of data waiting periods is determined and the interval of the transmitting devices S is determined so that the operating times of the receiving device R and the plurality of transmitting devices S powered by the batteries are the same, and a configuration is adopted in which communication is performed using these determined parameters.

[0034] With this configuration, even in a communication system combining devices from multiple companies, it is expected that the battery replacement intervals can be aligned within a certain range. Therefore, maintenance costs can be expected to be significantly reduced. [Explanation of Symbols]

[0035] C Repeater CL Cloud GW Gateway R Receiver S Transmitter 100 Central Control Unit 101 Sensor 102 Display device 103 Input device 104 Communication Control Unit 105 Wireless Transceiver Unit 200 Central Control Unit 201 Wireless Transceiver Unit 202 Communication Control Unit 203 Display device 204 External sending IF 205 Input device 211 Unit Reception Processing Execution Means 212 Daily receiving processing execution means

Claims

1. A single-unit receiving processing execution means executes a receiving process that consists of a receiving processing period that is a combination of a data waiting period in an operational state and a pause period in an inactive state, repeated n times to form one unit receiving processing period. A daily receiving processing execution means that repeats the aforementioned one-unit receiving processing period m times per day, A receiving device comprising, Multiple transmitting devices with a data transmission interval of T seconds In a communication system equipped with, A communication system characterized in that, when the plurality of transmitting devices transmit data over a period of T × a seconds, and the receiving process by the one-unit receiving processing execution means is performed for T × a seconds, the time of the data waiting period and the time of the pause period are determined and set according to the probability of the data that can be received by the receiving device relative to all transmitted data.

2. The communication system according to claim 1, characterized in that the receiving device and the plurality of transmitting devices are powered by a battery, the number of data waiting periods is determined and the interval of the transmitting devices is determined so that the operating times of the receiving device and the plurality of transmitting devices powered by the battery are the same.

3. A single-unit receiving processing execution means executes a receiving process that consists of a receiving processing period that is a combination of a data waiting period in an operational state and a pause period in an inactive state, repeated n times to form one unit receiving processing period. A daily receiving processing execution means that repeats the aforementioned one-unit receiving processing period m times per day, A receiving device comprising, Multiple transmitting devices with a data transmission interval of T seconds A communication method in a communication system comprising, A communication method in a communication system characterized in that, when the plurality of transmitting devices transmit data over a period of T × a seconds, and the receiving processing by the one-unit receiving processing execution means is performed for a period of T × a seconds, the receiving device determines the time for the data waiting period and the time for the pause period according to the probability of the data that can be received relative to all transmitted data, sets these times, and performs communication.

4. The receiving device and the plurality of transmitting devices are powered by batteries. A communication method in a communication system according to claim 3, characterized in that the number of data waiting periods is determined and the interval of the transmitting devices is determined so that the operating times of the receiving device and the plurality of transmitting devices by the battery are the same, and communication is performed using these determined parameters.

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