Bluetooth 4.0 is the latest Bluetooth version in 2012. It is an upgraded version of 3.0. Compared with version 3.0, it is more power-efficient, low-cost, low latency of 3 milliseconds, long effective connection distance, AES-128 encryption, etc.; usually used in Bluetooth headsets, Bluetooth speakers. And other equipment.
Speed: Supports ultra-short data packets at a data rate of 1 Mbps, with a minimum of 8 octets and a maximum of 27 hops. All connections use the Bluetooth 2.1 added sniff subrating to achieve an ultra-low duty cycle.
Frequency hopping: Use adaptive frequency hopping common to all Bluetooth specification versions to minimize crosstalk with other 2.4 GHz ISM band wireless technologies.
Main control: Smarter, can sleep longer, only wake up when it needs to perform actions.
Delay: The minimum connection setting can be completed in 3 milliseconds and start transmitting data.
Range: Increase the modulation index. The maximum range can exceed 100 meters (depending on the application field, the distance is different).
Robustness: All packets use 24-bit CRC check to ensure maximum protection against interference.
Security: Use AES-128 CCM encryption algorithm for packet encryption and authentication.
Topology: 32-bit addressing is used for each receive packet for each packet, theoretically connecting billions of devices; optimized for one-to-one connections and supporting one-to-many connections in a star topology; using fast connect and disconnect The data can be transferred within the mesh topology without maintaining a complex mesh network.