||A wireless sensor network(WSN) is formed by a number of sensors and a sink node in a specific area. The sensors gather interesting information like temperature, humidity, pressure, etc., and this information will be sent to a sink node. The sink node will calculate and analyze the collected information for proper applications. The power source of sensor is battery, i.e., a limited energy, which is an important parameter in WSNs, showing a research direction about how to design a power-saving mechanism for extending the entire network lifetime of a WSN system.|
In a coronal-based wireless sensor network, the network area is cut into multiple concentric corona circles, and the width of each adjacent concentric corona is the same.
The outer corona sensor will transfer data to the inner corona by passing through the sensor in the adjacent corona. The inner corona sensor will carry too much traffic, causing the life of inner nodes ending early, and the data of the outer corona sensor cannot be transmitted back to the sink node. Even though the sensors in the outer corona still have enough residual energy, the entire network may not run. This problem is known as energy holes, which has a great impact on the efficiency of the network.
Therefore, this thesis study proposes a method to apply Bluetooth Low Energy(BLE) technology into wireless sensor networks and optimize energy efficiency. Each sensor uses BLE for wireless transmission. The relay node which is selected by the maximum residual energy will send the data to a sink node directly. Then the inner corona sensor can avoid carrying too much traffic, and the power consumption can be balanced between sensors in inner and outer coronas. The simulation result shows that, selecting an applicable relay node which can mitigate the power consumption of inner corona nodes is able to extend the entire network lifetime of a WSN system.
|| Ayşe Berika Varol, "Compilation of Data Link Protocols: Bluetooth Low Energy (BLE), ZigBee and Z-Wave," in Proceeding of 2019 4th International Conference on Computer Science and Engineering (UBMK), Samsun, Turkey, 2019, pp. 85-90.|
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