Coded PHY is an optional Bluetooth Low Energy (LE) radio mode that uses forward error correction: it adds redundant information so a receiver can recover data more reliably when the signal is weak or noisy. This improves link robustness and can extend communication range, but reduces data throughput compared with faster LE modes.
In practice, devices may use Coded PHY for low-data-rate links such as sensors that need to communicate over greater distances. Actual range depends on both devices, antennas, radio settings, and the environment; the mode alone does not guarantee a particular distance or prove that a connection is authenticated. Security still depends on pairing, authentication, and application-level access controls.