Design Of Miniature And Low Power Wireless Sensor Network Node

In recent years,with the continuous improvement of people’s pursuit of quality of life,smart home related industries have developed rapidly.Wireless sensor networks are widely used in the field of smart home because they can establish networks and interact with data and instructions without cables.Because of its concealment,the miniaturized wireless sensor network node can effectively reduce its impact on the indoor layout.Therefore,it has strong practicability.On the other hand,miniaturization also greatly limits the size of energy storage devices that can be carried,which greatly reduces the service life of nodes.In view of the above problems,a wireless sensor network node miniaturization scheme is proposed in the background of smart home indoor temperature monitoring.This scheme not only realizes the self power supply function of wireless sensor network nodes through light energy collection,but also uses energy-saving policy to reduce node power consumption and enhance the survivability of nodes without light.The specific research contents are as follows:1、In order to reduce the size of the node,the node circuit modules are laid out on three printed circuit boards and wired on both sides,and then stacked and connected.Aiming at the problems of large size and high pin density of the traditional connection interface,the special connection layer is designed by using the printed circuit board,and through the cooperative layout of the circuit structures of different layers of the node,the devices of different layers are buried in the hollowed connection layer,which reduces the size of the node to 16×14×8.7 mm~3.2、For the problem of short node life caused by limited battery energy under miniaturization,a small-size photodiode is used to collect light energy,and the collection efficiency of ambient light energy is improved by adjusting the proportion of the maximum power point of the energy collection circuit.At the same time,by changing the power management strategy of the operating system and intelligently regulating the performance parameters of the node according to the current energy storage and environmental energy,so as to ensure the continuous operation of the node.The average current consumption of nodes collecting and sending a set of data per minute is about 3.6μA.And when the illumination intensity is 500 Lux,the task execution with almost zero consumption can be realized.The final test results show that the designed smart home temperature monitoring wireless sensor network node can realize the temperature acquisition and data transmission function based on Zig Bee protocol in the indoor environment,the networking communication distance is about 11 m,and can realize the self power supply function under the daily light intensity.