Interference is one of the biggest challenges for any wireless technology to achieve reliable data communication. Different from wired data communication technology, wireless technology must share the transmission medium, and multiple devices may try to communicate in the same wireless spectrum, in the same general area, and at the same time. When this happens, in-air collisions will occur between data packets, which may make the receiving device unable to read the data packets, causing packet loss.
This challenge is particularly serious in unlicensed bands such as the global ISM band. In such frequency bands, a communication technology needs to adapt to potential interference from other devices using the same communication technology and devices using other communication technologies in the same frequency band.
Here are some principles adopted in Bluetooth communication to enhance the reliability of wireless communication:
1. Small and fast packets
If you want to avoid conflicts, it is best to choose small and fast packets. For example, compared with other low-power wireless mesh network technologies, the size of Bluetooth data packets is usually only half, but the speed is four times that of other technologies. Small and fast data packets can use the spectrum more efficiently and greatly reduce the probability of collisions.
2. Adaptive frequency hopping
Spread spectrum technology can improve the flexibility of wireless technology in a busy radio environment. In a busy radio environment, conflicts and interference are more likely to occur. Adaptive Frequency Hopping (AFH) is a unique spread spectrum technology used by Bluetooth technology to avoid interference.
