Communication method and mobile terminal

A system, comprising:

• a primary device, and
• a secondary device including a Bluetooth chip, a first power amplifier disposed inside the Bluetooth chip and a second power amplifier disposed outside the Bluetooth chip, the secondary device being connected with the primary device via a Bluetooth connection,
• wherein the secondary device is configured to
• obtain a first received signal strength indicator (RSSI) sent by the primary device;
• when the first RSSI is less than a first threshold, switch on a second power amplifier, the secondary device being connected with the primary device via the Bluetooth connection based on the first power amplifier and the second power amplifier;
• obtain a second RSSI sent by the primary device;
• when the second RSSI is greater than a second threshold, switch off the second power amplifier, the secondary device being connected with the primary device via the Bluetooth connection based on the first power amplifier,
• wherein the secondary device comprises a power control table comprising a high gain class indicating a high output power of the first power amplifier and a low gain class indicating a low output power of the first power amplifier, wherein
• when the first RSSI is less than the first threshold, the power control table is adjusted to the low gain class;
• and when the second RSSI is greater than the second threshold, the power control table is adjusted to the high gain class.