First, BLE technology has focused on reducing power consumption since its design. Compared with classic Bluetooth, BLE uses fewer advertising channels and shorter RF on-time. Traditional Bluetooth devices usually use 16 to 32 channels for broadcasting, while BLE uses only 3 advertising channels, and the RF on-time is reduced from 22.5 milliseconds to 0.6 to 1.2 milliseconds for each broadcast. This change significantly reduces the power consumption caused by broadcasting data.
Secondly, BLE designed a deep sleep state to replace the idle state of traditional Bluetooth. In the deep sleep state, the power consumption of BLE devices is extremely low and almost negligible. In addition, the protocol is also optimized for this communication mode, and the data transmission interval is increased to 0.5 to 4 seconds, and the amount of data sent by sensor applications is much less than usual. At the same time, all connections use the advanced sniffing (Sniff-Subrating) function mode to further reduce RF energy consumption.
Furthermore, the connection mechanism of BLE has also been optimized to achieve low power consumption. BLE connection is achieved transiently. When a command or status needs to be sent, the connection can be established very quickly and disconnected quickly after completion. Through the improvement of the connection mechanism, the device connection establishment process under BLE can be controlled to be completed within 3 milliseconds, and the connection is closed immediately after the approved data transmission is completed at a transmission speed of several milliseconds. Under the traditional Bluetooth protocol, it takes 100 milliseconds to establish a link layer connection, and it takes longer to establish a connection at the L2CAP (Logical Link Control and Adaptation Protocol) layer, usually taking a few seconds. This fast connection and disconnection mechanism significantly reduces the power consumption of BLE devices.
BLE also supports ultra-short data packet transmission, which makes it take less time to send data, thereby reducing power consumption. Compared with traditional Bluetooth, BLE can support data packets of 8 to 27 bytes, while traditional Bluetooth data packets are usually larger. The faster startup time also shortens the waiting time for transmission and reception, further reducing power consumption.
In terms of protocol stack, BLE adopts a simplified protocol stack design, using only one protocol to implement functions such as server discovery, name discovery, and information reading and writing. This is much less overhead than the classic Bluetooth with multiple protocols, which also contributes to reducing power consumption.
The ble bluetooth module also adopts an asymmetric architecture design, that is, the slave device mainly performs some simple operations without complex processing. This can effectively reduce power consumption and reduce costs. The master device is responsible for complex operations and tasks such as encryption and system synchronization timing. This design enables BLE devices to minimize power consumption while maintaining necessary functions.
The ble bluetooth module usually switches between different power consumption levels to adapt to different usage scenarios. By selecting the appropriate power consumption level, battery life can be extended. At the same time, BLE devices also support intelligent connection management, including adjusting the broadcast frequency and connection interval, etc., to dynamically manage connections according to the actual needs of the device. This intelligent connection management mechanism helps to further reduce the power consumption of BLE devices.
The ble bluetooth module achieves low power consumption characteristics through a variety of technical means such as reducing the broadcast channel and RF opening time, designing deep sleep state, optimizing the connection mechanism, supporting ultra-short data packet transmission, adopting a simplified protocol stack design, adopting an asymmetric architecture design, and supporting intelligent connection management. With the combined effect of these technical means, the BLE Bluetooth module has been widely used in the fields of Internet of Things, smart home, health monitoring, etc.
