Abstract
Saving energy is gradually becoming a trend because of the aggravating consequences of the greenhouse effect on our lives. Saving 10% of energy can reduce the production of carbon dioxide by 10%. Portable devices use power from battery cells. Since energy is limited, we should be concerned about energy consumption to achieve goals. In this thesis, the system architecture and logic design of the Link Layer (LL) of Bluetooth Low Energy (BT-LE) are proposed. The proposed system contains an LL controller, data stream, interface with PHY, and interface with host. We define the operation mode for BT-LE by analyzing the protocol. The power mode is used to estimate energy consumption. Furthermore, we use the result of the analysis to program the estimation software for energy consumption. After understanding the protocol, we propose four methods. We find the timeout mechanism inefficient and propose a method to improve its efficiency. Thus, we propose a new timeout mechanism with 89% efficiency when the timeout window is changed and timeout is adapted. We also propose the method of putting devices into idle or power-down mode which saves energy when BT-LE enters the sleep state. Another method involves adjusting the duration of advertisements by considering the number of nearby scanners. This method achieves 80% efficiency. The last method which adapts timeout when the link is established, the data rate is adjusted by SNR. When the SNR is higher than the threshold, we raise the data rate to increase the sleep time. This achieves 49% efficiency. In conclusion, this study may improve the energy consumption of BT-LE through a simple method.