PAAS platform-based ultra-low power consumption soil near-ground wireless sensing system

Abstract

A PaaS platform-based ultra-low power consumption soil near-ground wireless sensing system includes a plurality of sensors mounted in soil, a signal transceiver module is arranged in the sensor, the signal transceiver module transmits a signal to a LoRaWan gateway through LoRa wireless communication, and the LoRaWan gateway is successively connected to a PaaS platform and a user group; and the sensors include a soil moisture sensor, a soil salinity sensor and a rainfall sensor. The PaaS platform-based ultra-low power consumption soil near-ground wireless sensing system of the invention enables sensor nodes to have ultra-low power consumption; and through fusion with a LoRa communication technology, a node network with ultra-low power consumption and long-distance transmission is constructed.

Claims

1. A PaaS platform-based ultra-low power consumption soil near-ground wireless sensing system, comprising a plurality of sensors mounted in soil, wherein a signal transceiver module is arranged in the sensor, the signal transceiver module transmits a signal to a LoRaWan gateway through a LoRa wireless communication, and the LoRaWan gateway is successively connected to a PaaS platform and a user group; and the plurality of sensors comprise a soil moisture sensor, a soil salinity sensor and a rainfall sensor; wherein a sampling period of the soil moisture sensor is $T\left(n+1\right)-T\left(n\right)*\frac{\Delta }{.Math.\theta \left(n\right)-\theta \left(n-1\right).Math.}*1/R*E_0,$  T(n) is an n.sup.th sampling period of the soil moisture sensor, θ(n) is a soil moisture value acquired by the sensor, Δ is a maximum allowable deviation of two data before and after maintaining a data integrity, R is a rainfall grade, and E.sub.0 is an empirical parameter, wherein R is real-time weather forecast data, R is obtained by measured rainfall of the rainfall sensor, and values of R are 1, 2, 3, 4, 5, 6 and 7, which are sequentially increased, and respectively represent no rain, light rain, moderate rain, heavy rain, excessive rain, torrential rain and extraordinary rain, and E.sub.0 serves as an empirical parameter, which is capable of adjusting the sampling period to a suitable value at an initial stage according to actual application requirements.

2. The PaaS platform-based ultra-low power consumption soil near-ground wireless sensing system according to claim 1, wherein the sensor is connected to a ternary lithium battery through a voltage boosting device, the ternary lithium battery is connected to the signal transceiver module through a voltage reducing device, and a controller is connected between the sensor and the signal transceiver module.

3. The PaaS platform-based ultra-low power consumption soil near-ground wireless sensing system according to claim 2, wherein a wireless charging coil is arranged outside the ternary lithium battery, and a casing is sheathed outside the wireless charging coil.

4. A using method of the PaaS platform-based ultra-low power consumption soil near-ground wireless sensing system according to claim 2, comprising the following steps of: (1) distributing the soil moisture sensor, the soil salinity sensor and the rainfall sensor in a study area, and debugging the whole wireless sensing system; (2) setting a maximum allowable deviation Δ and an initial sampling period T(0) of the sensor; (3) transmitting sensor data to the PaaS platform through a LoRa communication module, and storing the sensor data by the PaaS platform; and (4) calculating a deviation M of two adjacent sampling data, and calculating a sampling period according to a formula $T\left(n+1\right)-T\left(n\right)*\frac{\Delta }{.Math.\theta \left(n\right)-\theta \left(n-1\right).Math.}*1/R*E_0.$

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a constitutional diagram of a system of the present invention.

(2) FIG. 2 is a schematic constitutional diagram of a power supply of the present invention.

DETAILED DESCRIPTION

(3) The present invention is further described hereinafter with reference to the accompanying drawings.

(4) As shown in FIG. 1 and FIG. 2, a PaaS platform-based ultra-low power consumption soil near-ground wireless sensing system of the present invention includes a plurality of sensors mounted in soil, wherein a signal transceiver module is arranged in the sensor, the signal transceiver module transmits a signal to a LoRaWan gateway through LoRa wireless communication, and the LoRaWan gateway is successively connected to a PaaS platform and a user group. The sensors include soil near-ground sensors such as a soil moisture sensor, a soil salinity sensor and a rainfall sensor, and real-time data of the rainfall sensor is used as parameters for calculating a sampling period T of the soil moisture sensor.

(5) In the present invention, the sensor is connected to a ternary lithium battery through a voltage boosting device, the ternary lithium battery is connected to the signal transceiver module through a voltage reducing device, and a controller is connected between the sensor and the signal transceiver module. A wireless charging coil is arranged outside the ternary lithium battery, and a casing is sheathed outside the wireless charging coil. The sampling period of the soil moisture sensor is

(6) $T\left(n+1\right)-T\left(n\right)*\frac{\Delta }{.Math.\theta \left(n\right)-\theta \left(n-1\right).Math.}*1/R*E_0,$
T(n) is an n.sup.th sampling period of the soil moisture sensor, θ(n) is a soil moisture value acquired by the sensor, Δ is a maximum allowable deviation of two data before and after maintaining a data integrity, R is a rainfall grade, and E.sub.0 is an empirical parameter. R is obtained by measured rainfall of the rainfall sensor, and values of R are 1, 2, 3, 4, 5, 6 and 7, which are sequentially increased, and respectively represent no rain, light rain, moderate rain, heavy rain, excessive rain, torrential rain and extraordinary rain, and E.sub.0 serves as an empirical parameter, which is capable of adjusting the sampling period to a suitable value at an initial stage according to actual application requirements, and in a case of artificial irrigation, the initial sampling period T0 may be corrected in real time. When a difference between two data of the sensor before and after does not exceed Δ, the sampling period will be gradually increased according to the formula; and when the difference exceeds Δ, the sampling period will be shortened through proportional adjustment. Therefore, a total working time of the sensors can be reduced through proportional adjustment of the sampling period while ensuring a validity and an integrity of data, and a sleeping time of the sensor node is maximized, thus prolonging one field working time of a sensor battery.

(7) A using method of the PaaS platform-based ultra-low power consumption soil near-ground wireless sensing system includes the following steps. (1) The soil moisture sensor, the soil salinity sensor and the rainfall sensor are distributed in a study area, and the whole wireless sensing system is debugged. (2) A maximum allowable deviation Δ and an initial sampling period T(0) of the sensor are set. In an initial stage of distribution of the sensors, the sampling period is set to be unchanged, that is, T(0)=T(1), and sampling is carried out to obtain first two sampling data θ(0) and θ(1). If there is no rainfall, R=1, and a third sampling period

(8) $T\left(2\right)-T\left(1\right)*\frac{\Delta }{.Math.\theta \left(1\right)-\theta \left(0\right).Math.}*1/R*E_0$  is calculated according to the formula. Calculating M=|θ(1)−θ(0)|, if M<=Δ, the change of two sampling data before and after falls within an allowable range, and according to the formula, the sampling period will be increased; and if M>Δ, the sampling period will be reduced. An appropriate empirical value E.sub.0 is set according to experience to adjust a change speed of the sampling period. (3) Sensor data is transmitted to the PaaS platform through a LoRa communication module, and the sensor data is stored by the PaaS platform. (4) A deviation M of two adjacent sampling data is calculated, and a sampling period is calculated according to a formula

(9) $T\left(n+1\right)-T\left(n\right)*\frac{\Delta }{.Math.\theta \left(n\right)-\theta \left(n-1\right).Math.}*1/R*E_0.$  If M<=Δ, the change of the two sampling data before and after falls within the allowable range, the sampling period will be increased according to the formula; and if M>Δ, the sampling period will be reduced. It can be seen from the formula that the sampling period T will always be dynamically adjusted and continuously optimized to make the sensors obtain maximum sleeping time while maintaining an integrity of the sampling data, so as to satisfy a requirement of maintaining the sensor nodes to work for a long time through single power supplying of a single battery.

(10) The above method of the present invention has many advantages, for example, 1) the ultra-low power consumption hardware structure is used in the present invention to enable the sensor nodes to have ultra-low power consumption, so that maintaining the nodes to work for a long time through single power supplying of a single battery is satisfied; and through fusion with a LoRa communication technology, a node network with ultra-low power consumption and long-distance transmission is constructed, and economic values of existing sensors are fully achieved. 2) The sensor nodes may also receive external commands, and transmit the commands from the user application platform to modify parameter settings of the nodes. According to actual application requirements, the sampling period is adjusted proportionally according to the formula, and a total working time of the sensors can be reduced while ensuring a validity and an integrity of data, thus prolonging one field working time of a sensor battery. 3) Single-battery multi-output global power supplying is used in the node of the soil near-ground sensor of the present invention, which simplifies the hardware structure without needing to be connected to commercial power or solar energy, thus avoiding cable connection during mounting, realizing real “wireless”, and greatly facilitating application deployment in the field. In addition, due to a super connection load capacity of the LoRa gateway, only a few solar power supply systems need to be mounted during large-scale networking. 4) When being consumed, a node battery may be recharged wirelessly and then reused, without reserving a charging interface or a detachable battery structure, and the node battery is cured and packaged with black flame-retardant epoxy resin as a whole, with a high mechanical strength, a heat resistance, a water resistance and a corrosion resistance, thus being really maintenance-free or convenient to maintain in the later period. 5) Through development based on the PaaS platform of the operator, the soil near-ground wireless sensor system with mass connection, data storage, device management, rule engine and event warning is constructed, and an efficient, stable and safe application platform is built between a sensor device and a user. The user may also transmit instructions from the application platform to the network nodes, so that the nodes have a working mode that the period is adjustable and the nodes may be waked up in real time to satisfy multiple application scenario requirements.

(11) Those described above are merely the preferred embodiments of the present invention, and it should be pointed out that those of ordinary skills in the art may further make improvements and decorations without departing from the principle of the present invention, and these improvements and decorations should also be regarded as the scope of protection of the present invention.